Flood Monitoring System

Sensors 2012, 12, 4213-4236; doi:10. 3390/s120404213 OPEN ACCESS sensors ISSN 1424-8220 www. mdpi. com/journal/sensors Article A Real-Time Measurement System for Long-Life Flood Monitoring and Warning Applications Rafael Marin-Perez 1, , Javier Garc? a-Pintado 2,3 and Antonio Skarmeta G? mez 1 ? o 1 Department of Information and Communication Engineering, University of Murcia, Campus de Espinardo, E-30100, Murcia, Spain; E-Mail: [email  protected] es 2 Euromediterranean Water Institute, Campus de Espinardo, E-30100, Murcia, Spain; E-Mail: [email  protected] om 3 National Centre for Earth Observation, University of Reading, Harry Pitt Building, 3 Earley Gate, Whiteknights, Reading RG6 6AL, UK Author to whom correspondence should be addressed; E-Mail: [email  protected] es. Received: 7 February 2012; in revised form: 14 March 2012 / Accepted: 22 March 2012 / Published: 28 March 2012 Abstract: A ? ood warning system incorporates telemetered rainfall and ? ow/water level data measu red at various locations in the catchment area. Real-time accurate data collection is required for this use, and sensor networks improve the system capabilities.However, existing sensor nodes struggle to satisfy the hydrological requirements in terms of autonomy, sensor hardware compatibility, reliability and long-range communication. We describe the design and development of a real-time measurement system for ? ood monitoring, and its deployment in a ? ash-? ood prone 650 km2 semiarid watershed in Southern Spain. A developed low-power and long-range communication device, so-called DatalogV1, provides automatic data gathering and reliable transmission. DatalogV1 incorporates self-monitoring for adapting measurement schedules for consumption management and to capture events of interest.Two tests are used to assess the success of the development. The results show an autonomous and robust monitoring system for long-term collection of water level data in many sparse locations during ? o od events. Keywords: real-time data acquisition; sensor network; hydrological monitoring; ? ood warning system Sensors 2012, 12 1. Introduction 4214 A warmer climate, with its increased climate variability, will increase the risk of both ? oods and droughts [1], whose management and mitigation are important to protect property, life, and natural environment. Real-time accurate monitoring of hydrologic variables is key for ? od forecasting, as well as for optimizing related warning systems for damage mitigation. Recent studies show that in the speci? c case of semiarid and arid areas, adequate deployment of monitoring networks is essential to a real understanding of the underlying processes generating run-off in storm events, and to achieve effective emergency systems (e. g. , [2]). Traditionally, researchers have directly collected data at the places of interest. This has now been commonly substituted by automatic sensor and datalogger systems, which provide high temporal data resol ution, while reducing operational human resource requirements.Dataloggers permit local automatic and unattended data gathering, and reduce environmental perturbation. However, data retrieval from standard dataloggers and storage in processing and control/warning centers still has to be done either manually, which prevents its applicability in ? ood warning systems, or through wired connections, which leads to substantial investments and operational costs. To confront these problems, sensor network technology has been proposed in many monitoring applications [3]. Yet, speci? c literature on sensor network for ? ood forecasting is sparse, with only a few examples available (e. . , [4–8]). Basically, a sensor network comprises a set of nodes, where each node includes a processor, a wireless radio module, a power supply, and is equipped with sensor hardware to capture environmental data. Each node performs the tasks of data gathering, physical parameter processing, and wireless d ata transmission to the control server. Speci? cally, for hydrologic applications, sensor nodes must also ful? ll a number of additional requirements: †¢ Power lifetime: Power sources are often not available at the locations of hydrological interest.Moreover, these locations are usually unprotected, and if renewable energy devices are used, there are prone to vandalism or theft. Thus, sensor nodes must have low-consumption, which along with existing standard batteries, should last at least one hydrologic cycle. †¢ Sensor hardware compatibility: Most hydrologic sensor nodes include a datalogger device connected through a cable to one or more measurement instruments. The datalogger must provide multiple wired interfaces to be able to communicate with a range of speci? c sensor hardware interfaces.This also involves issues of power supply, and selective time for power dispatching, which leads to optimal power management and facilitates the expansion of connected instruments. †¢ Reliability: Harsh weather conditions may cause failures in the wireless communication over the monitoring network. Backup mechanisms in local sensor dataloggers must be used to avoid information losses in unexpected crashes. †¢ Long-range communication: Hydrologic measurement locations are commonly sparse over large areas, and far away from the control center (i. e. , tens or hundreds of kilometers).Sensor nodes must have a peer-to-peer connection with the control center. Sensors 2012, 12 4215 In general, these, sometimes opposing, requirements are dif? cult to be satis? ed by existing developed solutions. For example, multiple sensor readings and long-range communication are high power-consumption tasks, which diminish battery lifetime. For instance, many existing wireless solutions for agriculture applications (e. g. , [9–11]) use a set of tens or hundreds of motes, which collaborate to gather dense data in a small area. Motes have low consumption, but they pr ovide limited sensor interfaces, and short-range communication.On the other hand, several hydrologic and meteorologic applications have been implemented with a few wireless datalogger stations, which individually obtain multi-sensor data in a few sparse locations over a large area (e. g. , [5,12–14]). These dataloggers permit high computing and long-range communication. However, they have an excessive investment cost and a high consumption that may be, in the long-term, unsustainable. This paper describes the design, development, and deployment of a real-time monitoring system for hydrological applications.The paper is focused on the description in detail of our wireless datalogger device, so-called DatalogV1 [15], which combines the low consumption of motes and the reliable communication of most powerful multi-sensor datalogger stations in order to satisfy the requirements of ? ood warning system scenarios. The DatalogV1 provides automatic monitoring and long-term autonomy i n sparse points over large areas. To demonstrate the goodness of the DatalogV1 design, we deployed a monitoring network in the Rambla del Albuj? n watershed, in Southern Spain. The severity of ? ash ? ods in the Rambla del o Albuj? n has caused important environmental and economic damages over the last years. Accordingly, the o wireless monitoring network is intended to provide real-time accurate hydrologic information to support an operational model-based ? ood warning system. This is an excellent test to asses the DatalogV1 performance and success in a real case scenario. The remainder of the paper is organized as follows. Section 2 introduces the context of environmental monitoring and ? ood warning systems. Section 3 depicts our hydrologic monitoring scenario.Section 4 presents the design of DatalogV1 hardware. Section 5 shows the implementation of DatalogV1 software. Section 6 describes the architecture developed for remote hydrologic monitoring. Section 7 describes the deploym ent of the monitoring network in the Rambla del Albuj? n watershed. Section 8 shows the results o obtained regarding power consumption and data collection. Section 9 provides concluding remarks. 2. Environmental Monitoring Environmental monitoring is the most popular application for sensor networks. At present, sensor networks have been applied for a number of applications as, e. . , soil moisture monitoring [16], solar radiation mapping [17], aquatic monitoring [18], glacial control and climate change [19], forest ? re alarm [20], landscape ? ooding alarm [21], and forecasting in rivers [22]. The ability to place autonomous and low cost nodes in large harsh environments without communication infrastructure enables accurate data collection directly observed from interest areas. With sensor networks, environmental data can be observed and collected in real-time, and used for forecasting upcoming phenomena and sending prompt warnings if required.Sensors 2012, 12 2. 1. Model-Based Floo d Warning System Context 4216 The developed sensor network was incorporated within the context of a model-based ? ood warning system in the Rambla del Albuj? n watershed. A model-based ? ood warning system, for mitigating the o effects of ? ooding on life and property, incorporates a catchment model based on observed/forecasted rainfall and telemetered observations of hydrologic state variables at various locations within the catchment area. Generally, observed variables are ? ow and/or water level in channels.Also, other variables such as soil moisture and piezometric levels may be of interest, depending on the watershed response. Real-time updating of the ? ood forecasting involves the continual adaptation of the model state variables, outputs and parameters, so that the forecasts for various times into the future are based on the latest available information and are optimized, in some sense, to minimize the forecasting errors (e. g. , [23]). This is the process of data assimilati on. Implementation of environmental sensor networks for data assimilation within model-based ? ood warning systems involves complex engineering and system challenges.These systems must withstand the event of interest in real-time, remain functional over long time periods when no events occur, cover large geographical regions of interest to the event, and support the variety of sensor types needed to detect the phenomenon [8]. 3. Hydrological Monitoring and Forecasting in the Rambla del Albuj? n Watershed o The Rambla del Albuj? n watershed (650 km2 ) is the main drainage catchment in the Campo de o Cartagena basin, in Southern Spain (see Figure 1). The main channel in the watershed is 40 km long and ? ows into the Mar Menor; one of the big coastal lagoons in the Mediterranean (135 km2 ).The Campo de Cartagena basin is an area with semiarid Mediterranean climate, where the average temperature ranges from 14 o C to 17 o C, mean potential evapotranspiration is 890 mm yr–1 and me an precipitation is 350 mm yr–1 . Most rainfall comes in short-time storm events, and the watershed hydrologic response is highly complex and non-uniform. Previous studies have shown the complex ? ash-? ood response of the Rambla del Albuj? n watershed o and the importance of spatially distributed observation for adequate forecasting (e. g. , [2]). Also, for ? ooding evaluations, stage gauges provide an advantage over ? w gauges that the observations remain unbiased when ? ow goes out of banks, in which case the validness of calibrated rating curves (stage-? ow relationships) is prevented. In this sense, remotely-sensed information (from aerial photography and/or satellites) is appealing as it contains much more spatial information than typical stage gauge networks in operational watersheds. Accordingly, recent studies are evaluating the potential of aerial photography and remotely sensed (from satellites) synthetic aperture radar to provide measurements over large areas of w ater levels and ? od extents in lakes and rivers (e. g. , TerraSAR-X or COSMO-Skymed constellations [24]). However, the current low temporal frequency of satellite acquisitions relative to gauging station sampling indicates that remote sensing still does not represent a viable replacement strategy for data assimilation into model-based forecasts [25]. Also, before the ? ow goes out of banks, the accuracy of standard stage gauges is higher than that provided by airborne information, which is key for early warnings.Thus, if economically viable, a spatially distributed network of stage gauges remains the best option to capture the observations required to feed the forecasting and data assimilation processes. Sensors 2012, 12 4217 At the Rambla del Albuj? n watershed, we implemented a hydrological monitoring system consisting o on a network of stage gauges located at eight critical junction points between major tributaries. The monitoring locations were carefully chosen in order to achi eve effective water level monitoring during ? ood events and a reliable model-based forecasting system.Figure 1 shows the selected locations which are far away (? 50 km) from the control center at the University of Murcia, to the North of the watershed. In this area, an existing phone infrastructure enables the communication among the server in the control center and the DatalogV1s in the ? eld. The DatalogV1s must be autonomous only with batteries, because no power source exists in the monitoring area and solar panels are frequently stolen or vandalized. In the following sections, we describe the design and development of the DatalogV1 to provide remote data gathering of the water stage in channels during ? ods. Figure 1. Deployment scenario. The embedded image shows the location of the Rambla del Albuj? n watershed at the Southeast of the Iberian Peninsula. The violet line describes the o watershed boundary drawn on a digital terrain model (DTM). Within the watershed, the main cha nnel network is shown in blue, and labeled squares indicate deployed gauge locations. Sensors 2012, 12 4. Design of DatalogV1 Hardware 4218 The DatalogV1’s design was developed to address the requirements of the described application. The block diagram of DatalogV1 is illustrated in Figure 2(a).The critical components are a low-power microcontroller ( µC) module that supervises the DatalogV1’s operation, multiple sensor interfaces (Pulse, SDI-12, RS-485, Analog) that enable to take measurements from different kinds of sensor devices, and a GPRS module for long-distance communication with the control center. Moreover, two communication modules (USB and Bluetooth) enable the in-situ interactions via a laptop. All electronic components and a battery are mounted in an IP65 waterproof box to protect from harsh weather conditions, as shown by Figure 2(b).The DatalogV1’s design is balanced between low-power consumption for long-lifetime, and computational capability for multi-sensor reading and long-range communication. The hardware design of these components is described in the next subsections. Figure 2. Two different views of the DatalogV1. (a) Block diagram showing the main components. (b) The electronic components and the battery are mounted on a IP65 protection box. SDI-12 Interface RS-485 Interface Pulse Counters Analog Inputs Power Connector DC/DC Converter GPRS Module Linear Regulator Battery Connector Linear RegulatorMosfet Switch  µC DC/DC Converter Pulse Counters Bluetooth Module RS-485 Interface USB Module Battery Connector Power Connector Analogic Inputs SDI-12 Connector GPRS Module Bluetooth Module USB Module  µC (a) (b) 4. 1. Design of Microcontroller Module The circuit schematic of the microcontroller module is shown in Figure 3. The central part of the schematic represents the low-power 8-bits microcontroller (PIC18LF8722) manufactured by Microchip. The PIC18F8722 operating to 3. 3 V is ideal for low power applications ( n anoWatts) with 120 nW sleep mode and 25  µW active mode.It provides high processing speed (40 MHz) with a large 256 KB RAM memory. A 12 MB data? ash memory is included for local storage of sensor data. The top-left portion of the schematic (IC3) shows a security mechanism to avoid microcontroller blockage in case that available energy is not enough. Thus the microcontroller resets when there is less than 2. 4 V. The center-left part of the schematic contains the crystal oscillator setting to 11 MHz. (OSC1/OSC2 tags). The oscillator provides a precise clock signal to stabilize frequencies for sensor readings and data transmissions. Sensors 2012, 12 Figure 3.Circuit schematic of the microcontroller module. The center portion is the microcontroller used to control DatalogV1 operation, and the center-left is the crystal oscillator used for setting the clock. 4219 4. 2. Design of Sensor Interfaces DatalogV1 provides multi-sensor interfaces to take readings from a wide set of hydrologic instruments. Its sensor interfaces are two pulse counters, two digital connectors (RS-485 and SDI-12), and eight analog inputs. Each pulse counter reads from a tipping-bucket rain gauge (pluviometer) which generates a discrete electrical signal for every amount of accumulated rainfall.Digital interfaces supply power to and read measurements from instruments, which can themselves include some degree of computational capability. Analog connectors enable the reading of simple instruments which modify the supplying voltages to return voltage values proportional to the physical observed variables. These multiple interfaces are compatible with the most of hydrological sensor devices in the market. Pulse-counters typically connect to rain-gauge devices. The standard rain gauge collects the precipitation into a small container. Every time the container is ? led and emptied, it generates a electric pulse. According to the number of pulses and the size of the container, DatalogV1 estimates t he precipitation without requiring power supply. Sensors 2012, 12 4220 For each digital interface, DatalogV1 can supply and read multiple sensors. Both RS-485 and SDI-12 interfaces consist of three electronic wires for data, ground and supplying voltage. The RS-485 is a standard serial communication for long distance and noisy environments. In addition, the SDI-12 is a serial data interface at 1,200 baud designed for low-power sensors.Using serial protocols, DatalogV1 can directly obtain the physical measurements. The analog inputs allow to read 8 differential sensors, 16 single-ended sensors, or a combination of both options. A differential connection comprises four electronic wires acting as voltage-supplier, ground, positive-voltage, and negative-voltage, while a single-end connection contains two electronic wires for supplying-voltage and positive-voltage. The main difference between differential and single-ended is the way to obtain the voltage value. In single-ended, the volta ge value is the difference between the positive voltage and the ground at 0 V.However, single-ended connections are sensitive to electrical noise errors, which are solved by differential connections. Because twisting wires together will ensure that any noise picked up will be the same for each wire, the voltage value in differential inputs is the difference between the positive and negative voltages. Figure 4. Circuit schematic of analog interfaces. (a) Selector of analog connections to plugged-in sensors, (b) ADC converter from output voltage to digital data. (a) (b) To obtain the measurements of the physical variables, output voltages are processed using three main hardware components: multiplexer, ampli? r, and ADC converter. Two multiplexers MC74HC4051D from Motorola company enable to select the output voltage of a speci? c analog sensor (Figure 4(a)). Each multiplexer contains 3 control pins CA0, CA1, and CA2 to choose an output voltage among 16 possibilities. The selected outp ut voltage is ampli? ed for preserving high effective resolution. DatalogV1 uses an AD8622 ampli? er, manufactured by Analog Devices, that provides high current precision, low noise, and low power operation. The pre-con? gured ampli? cation depends on the output range Sensors 2012, 12 4221 of the selected sensor.Finally, the ampli? ed output signal is converted to a digital value through an Analog-Digital Converter (ADC), as shown by Figure 4(b). DatalogV1 contains a 13-bit ADC MCP3302, manufactured by Microchip, that provides high precision and resolution. This ? exible design provides full compatibility with presumably all kind of available sensors for hydrologic use. 4. 3. Design of GPRS Communication Module A GPRS module is used to transmit monitoring data from DatalogV1 to the control center. Figure 5 shows the GPRS module implementing all functions for wireless communications. Figure 5.Circuit schematic of the GPRS module. The center portion is the GPRS module used to control the long-distance communication, and the top-left portion is the SIM card connection. The top-left part of the circuit shows the connection of SIM phone-cards according to the manufacturer speci? cation. The bottom-left shows a uFL coaxial connector to the wireless antenna. We chose a Wavecom Q2686 chip, which is connected to the microcontroller via an USART interface (CS-USART). The Wavecom Q2686 contains a programmable 256 KB SRAM memory and includes a ARM9 32-bit processor at 104 MHz.This Q2686 chip makes possible to join a GSM/GPRS base-station and receive/send data reliably in quad-band communications on the 800, 900, 1,800 and 1,900 MHz Sensors 2012, 12 4222 bands. Also, the chip makes it easy to upgrade to 3G when needed. This GPRS module enables long-distance UDP/IP communications through cellular radio networks. 4. 4. Design of Power Module The power module consists of two power sources and three regulable mechanism to provide a secure supply of electronics components. The main energy source is a 12 V DC battery of 7,000 mAh power capacity which can be rechargeable using an optional solar panel.To adapt the input tension of the solar panel (17–20 V) to a lower tension (12–15 V) to supply the battery, we use a commutated DC/DC regulator in step-down mode, as shown by Figure 6(a). The microcontroller turns on the DC/DC regulator when it detects that the battery has a low level according to a pre-established threshold. Three circuits guarantee stable energy levels for battery, solar-panel, and sensors, as shown by Figure 6(b). The circuits of battery and solar-panel include security mechanisms to avoid a too low power level input to the sensors.For this, the circuit of sensors is used, before readings are taken, to check if the power supply is stable as to obtain an accurate measurement. Figure 6. Circuit schematic of the battery, solar-panel, and power-control modules. (a) Battery and solar modules, (b) secure power control for battery, so lar panel, and sensor. (a) (b) Figure 7. Circuit schematic of the power supply module. (a) Power supply for GPRS, sensors, and ADC converter, (b) power supply for microcontroller. (a) (b) To reduce the power consumption, DatalogV1 keeps almost all electrical components deactivated, such as GPRS, sensors, and ADC.Only the microcontroller circuit is always supplied at 3. 3 V Sensors 2012, 12 4223 (Figure 7(a)) through a linear regulator LM2936 from National Semiconductor with ultra-low current in the stand-by mode. This LM2936 regulator features low drop-out voltage (50 mA) to minimize power losses. Also, this circuit includes a diode (D10) to provide a security power to protect the microcontroller and all board at most 5 V. When it is necessary, the microcontroller supplies independently the electrical components using two DC/DC converters, two linear regulators and a MOSFET switch (Figure 7(b)).Concretely to supply sensors, a DC/DC converter and the MOSFET switch is combined to crea te a adjustable commutation cell. The design of the commutation cell includes high-power isolated chips in order to reduce interferences. At the same time, it has a good linearity and load regulation characteristics, and allows to establish the voltage supply between 3 V and 10 V. The chosen MOSFET is a FDC6330L, manufactured by Fairchild Semiconductor, which provides high performance for extremely low on-resistance (

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Maintenance and Plumbing Services - Essay Example This research will begin with the strength of the business. Maintenance and plumbing services offered by the business is enjoying various merits or strengths. The use of social platforms such as Facebook and Twitter is one of the ways that will envision the mission of the business to another level in the market. The target will be enlarged via marketing through social media; however, in order to meet the full potentials of the business, the management will consider using brand promotion. The business will adopt an artistic approach such as using famous artists to advertise a product via social media.   The business is using powerful digital resources to get a grip on the target market as compared to the competitors. This is considered as an added advantage to the business. Despite the fact that the business is using this approach to meet its goals and objectives, it should consider other clients with limited digital access. Thus, the business will also consider bringing other marke ting strategies such as the use of hard digital materials as the use of bronchus. In addition, the business will also use billboard and posters to meet the potential clients who have infinite digital distance. Enjoying weaknesses of the competitors places Mp services an upper hand in the business. For example, its competitors are not embracing the use of digital marketing and online plans to meet their target market.

Research & Analysis Study of Balfour Beatty plc Business and Essay

Research & Analysis Study of Balfour Beatty plc Business and Competitive Environment - Essay Example The company made good progress in the building sector in 2006. Heery, a leading architectural, engineering and programme management business, represents Balfour Beatty's business interests in USA. Balfour Beatty's Civil and Specialist Engineering and Services division, with revenues of 1,920m and 10,455 employees, specializes in engineering, design and management services provider in civil, transport, energy and water sectors in UK, USA, Hong Kong and Middle East. It has a leading market presence in specialised engineering services like overhead transmission lines, gas and water utility contracting and in road management and maintenance resulting in profit from operations tripled to 49m in 2005. The company with strong orders and a number of large contracts under their belt gained growth momentum in 2006 in the engineering sector. Balfour Beatty's Rail Engineering and Services division, with revenues of 766m and 5,922 employees, specializes in designing, constructing, equipping, maintaining and renewal of rail assets and systems in UK, USA, Germany, Italy and Portugal. The profit from operations in these services fell by 27% to 32m in 2005. This was a result of full year without maintenance and tighter market in UK and some losses in the US. 2006 saw some progress due to increase in efficiency and improving project volume in London Underground, Germany and Italy. Balfour Beatty Rail Inc has been restructured into a single organisation, headquartered in Jacksonville, Florida, USA. The organisation has shown substantial growth in recent years with strategic acquisitions in the US and Germany. Balfour Beatty's Investments and Developments division, with revenues of 465m and only 136 employees promotes, manages and invests in privately funded infrastructure projects and developments in selected sectors in the UK and overseas, through its operating company Balfour Beatty Capital, established in 1997. Balfour Beatty's is currently conducting PPP/PFI projects in two principal sectors such as infrastructure (comprising transportation, power and waste water treatment) and accommodation (including health and education). It showed 20m profit from operations in 2005. Balfour Beatty's Other Service Segments Balfour Beatty holds 20% share in the Metronet consortium, a 30-year PPP project responsible for upgrading and maintaining two thirds of London Underground's infrastructure like trains, stations, signalling, track, tunnels and bridges. Balfour Beatty also has four DBFO (design-build-finance-operate) road concessions. Balfour Beatty is provider of a range of Healthcare services to major UK hospital schemes in London, Edinburgh, Durham and Blackburn providing a total of over 2,500 beds. Through Consort Healthcare, Balfour Beatty is also appointed preferred bidder for 521m PPP contracts in Birmingham Acute and Adult Psychiatric Hospitals and 250m Pinderfields and Pontefract hospitals. Balfour Beatty operates the largest grouped schools scheme in England called the Transform Schools' Stoke concession covering 98 schools since 2000. The Rotherham Schools started in 2003, was awarded "Best Community Use Project" in 2005 in the PPP/PFI Journal Awards. The Transform scheme built and maintained 21

The Impact of Culture on Best Practice Production Management Essay

The Impact of Culture on Best Practice Production Management - Essay Example Services industry is the fastest growing segment in the world economy and the biggest challenge is customer satisfaction which depends upon service quality (Bick, Abratt & Moller, 2010). Customer service excellence becomes essential to achieve customer satisfaction which in turn translates into customer loyalty. Organisations are convinced that customer service delivers benefits and hence quality management programmes have been created that relate the service attributes to how customers would evaluate quality (Bolton & Drew, 1991). This implies that people skills are essential for personal and organisational success. Customer service excellence is based on customer insight, segmentation and leadership (CSE, n.d.). Segmentation helps to understand the needs of the customers which differ across cultures. Segmentation is implemented through the process of identifying and differentiating between groups that have similar needs or wants. By focusing on their needs, motivation and choices, the organisation can achieve customer service excellence as they realize that one-size-fit-all approach in not applicable in the service industry. Customer service excellence operates at three distinct levels – as a driver of continuous improvement, as a skills development tool and as an independent validation of achievement. Culture, according to Hofstede, â€Å"is the collective programming of the mind which distinguishes the members of one group or category from another† (Hope & Muhlemann, 2001). It has also been defined as the â€Å"software of the mind...† and culture is the way that a group of people solve problems and reconcile dilemmas (Lorenzoni & Lewis, 2004). Moreover, customers from different backgrounds also have differing levels of literacy which influences the evaluation of performance standards (Pizam & Eliss, 1999).Cultural difference cause differences in expectations, goals, values and proposed course of action. Cultural differences impact the belongingness, love and esteem needs of individuals and these principles reverse the Maslow’s hierarchy of needs theory. Subtle cultural differences cannot be ignored as the direct impact can be observed in decisions, outcomes and delivery of service (Korac-Kakabadse & Kouzmin, 1999). To achieve service excellence organisations would have to ensure that employees are adequately trained in the different elements of culture that manifest in many ways. Manifestation of cultural differences can be found in language and communication styles, in expression of emotions and body language, in social customs and eating habits. The deepest and the most ingrained manifestation of culture is the cultural assumptions from which stem the norms and values (Lorenzoni & Lewis, 2004). The most visible manifestation of culture is everyday behavioural standards. Hofstede has identified four different dimensions on which culture can be measured. These include the power distance, individualism, unc ertainty avoidance and masculinity. Cultures distinguish people in how they behave, maintain relationships and relate to each other in a variety of ways. It also influences the attitude towards time and the attitude towards the environment. All these factors heighten the importance of ensuring that employees are trained in understanding the nuances of different cultural backgrounds before customer service excellence can be expected. The hospitality industry is diverse in nature and each customer is individual in his/her needs and wants. The same customer may have different needs and demands in different situations (Baum & Nickson, 1998). Cultural differences impact the outcome of business because according to Hofstede different cultures imply different mental programming (Gilbert & Tsao, 2000).

Genetic engineering Essay Example for Free

Genetic engineering Essay Genetically modified foods (GM foods) have made for big talk in the public lately. Public interest groups have been actively protesting against GM foods for months. In response to the up swelling of public concern, the U. S. Food and Drug Administration (FDA) have held meetings to solicit public opinions and, begin the process of establishing a new regulatory procedure for government approval of GM foods. I would like to research and maybe, explain the reasons why I feel that GM foods are not humanitys solution to our food consumption problem. What are Genetically Modified Foods? Genetically modified foods are foods produced from organisms that have had specific changes introduced into their DNA using the methods of genetic engineering. These techniques have allowed for the introduction of new crop traits as well as a far greater control over a foods genetic structure than previously afforded by methods such as selective breeding and mutation breeding (Wikapedia. com). To date most genetic modification of foods have primarily focused on cash crops in high demand by farmers such as soybean, corn, canola, and cotton seed oil. These have been engineered for resistance to pathogens and herbicides and better nutrient profiles. GM livestock have also been experimentally developed, although as of November 2013 none are currently on the market. There are many reasons to not be a fan of GM foods but, before I explain the reasons not to consume GM foods, let me tell you some reasons why scientists and so-called, â€Å"experts†, are pushing to have developers and, manufacturers of GM foods make sure, that they are various advantages of consuming these foods, as well as, persuade the public to purchase these products. Are there advantages to GM Foods? One advantage to GM foods is that they help to control certain diseases that can cause people to have an allergic reaction to certain foods. With GM foods the DNA system is modified to eliminate the properties causing these allergies (http://www. buzzle. com/articles/genetically-modified-foods-pros-and-cons. html). Another advantage to GM foods is that they are said to be high in nutrients and contain more vitamins than traditionally grown food. They also claim to have a longer shelf life than traditionally grown food, which means less waste. Now that we have heard why developers, manufacturers, and scientists want GM foods massively produced, lets hear about some of the reasons why most of the population is not so accepting. Threats The biggest threat caused by genetically modified foods is that they can have harmful effects on the body (http://www. csa. com/discoveryguides/gmfood/overview. php). It is believed that consumption of these foods can cause the development of diseases which are immune to antibiotics. According to experts, people who consume these foods have high chances of developing cancer (http://www. csa. com/discoveryguides/gmfood/overview. php). Because these are new inventions on food, theres not much known about the long-term effects that genetically modified foods will have on humans. Foodstuffs made of genetically modified crops that are currently available (mainly maize, soybean, and oilseed rape) have been judged safe to eat, and the methods used to test them have been deemed appropriate. These conclusions represent the consensus of the scientific evidence surveyed by the International Council for Science (ICSU) and are consistent with the views of the World Health Organization (WHO). However, the lack of evidence of negative effects does not mean that new genetically modified foods are without risk. The possibility of long-term effects from genetically modified plants cannot be excluded and must be examined on a case-by-case basis. New techniques are being developed to address concerns, such as the possibility of the unintended transfer of antibiotic-resistance genes. Earlier, I mentioned an advantage to GM foods that allows them to be modified to eliminate properties within certain foods, so that people do not have an allergic reaction to them. My question is, â€Å"what in the world makes these developers think that we want to eat anything that has been modified†? Not to mention, knowing that the long-term effects are not certain if I consume one of these products. Thats not comfortably sitting on my stomach! Response These developers and, manufacturers claim that GM foods contain more vitamins and nutrients, along with a longer shelf life than traditional foods. The way the public sees it is the genetically modified anything, cannot be better for you than the real thing. Throughout my research, I have found that most of societys response to GM foods is, â€Å"why fix something thats not broken†? Most of society throws criticisms towards genetically modified foods, criticizing agribusinesses for pursuing profit without concern for potential hazards, and the government for failing to exercise adequate regulatory oversight (http://www. csa. com/discoveryguides/gmfood/overview. php). Concerns The most concerns about genetically modified foods falls into three categories: environmental hazards, human health risks, and economic concern. Environmental hazards are causes of unintended harm to other organisms. For example; the pollen blown around by the wind off of a GM plant, stands a chance of becoming involved with the milkweed plants that often grow near these crop fields. The concern is for the monarch butterfly, monarch butterflies eat milkweed plants and, if the butterflies eat the milkweed plant with the pollen from the GM plant on it, the butterflies then stand a chance of dying if they come in contact with this pollen. This could create a huge problem for the monarch butterflies extinction rate. Human health risks contain allergencity, which are allergies to things like peanuts and other foods. The possibility still remains that introducing a gene into a plant may create a new allergen that will cause someone to have an allergic reaction and, they could possibly die from that. Economic concern is the most talked about category out of all three. Things like, putting farmers out of business and bringing this product to the market is a costly process, as well as the tech companies wishing to turn a profit on their investment. Consumer advocates are worried that patenting new plants will raise the price of seed. When the prices of seed goes up, the farmers in third world countries cannot afford to purchase the seeds each year. No seeds means no crops for the farmers, no crops means no money. Conclusion Consumers may wish to select conventional foods on the basis of several criteria such as methods of production (e. g. organic or fair-trade food), religious principles (e. g. kosher food), or the presence of known allergens (e. g. groundnuts). Labeling of foods as genetically modified or non-genetically modified may enable consumer choice as to the process by which the food is produced. However, it conveys no information as to the content of the foods, and what risks or benefits may be associated with particular foods. More informative food labeling, explaining how food has been transformed and what the resulting changes in food composition are, could enable consumers to assess these risks and benefits (http://www. greenfacts. org). Genetically modified foods is a big deal in todays society, many people have a very strong opinion about GM foods. Many people are also unaware of what a genetically modified food is. Most people consume genetically modified foods on a daily bases and do not even realize it. Nor is the government obligated to inform you that you are consuming genetically modified foods. Throughout my research, I have found out why I feel that GM foods are not humanitys solution to our food consumption problem. Throughout my argument, I have tried to explain the good and, the bad things associated with genetically modified foods. I have come to the conclusion that genetically modified foods are not for me or my family. There are too many health issues and, risks that I am not willing to take because my familys health may lay in the balance. References Kartha, D. , Cheap Non-GMO Food Supply (2012) Retrieved from: http://www. buzzle. com/articles/genetically-modified-foods-pros-and-cons. html. Whitman, D. Genetically Modified Foods Harmful or Helpful? (2000) Retrieved from: http://www. csa. com/discoveryguides/gmfood/overview. php. Bottemiller, H. , Vilsack Calls for a Truce in GE Crops Fight. (2010) Retrived from: http://www. foodsafetynews. com/2010. Published under the authority of the GreenFacts Scientific Board at; (http://www. greenfacts. org). Definition of Genetically Modified Foods, (2000). Wikapedia. com.

Animals Under Threat of Extinction

Animals Under Threat of Extinction More than 16,000 species of animals, birds, fish and plants are under serious threat of becoming extinct. Why is this, and is there anything we can do with it? Introduction: The panda, the tiger, the blue whale and the mountain gorilla. These are just a few examples of animals critically endangered with extinction. In fact, according to the IUCN Red List, about 22 percent of all mammal species are threatened by extinction. In this assignment, I will consider a statement in our English book; More than 16,000 species of animals, birds, fish and plants are under serious threat of becoming extinct. I chose this statement because I hadnt really considered the fact before, and was shocked after having done some research to find what extinction of that many species could mean to our planet. All I know at this point is what it says in the statement. What I would like to know after having written the assignment is whether this affects us or not and if it is a global problem. I would like to learn about extinction in general, and how species actually are extinct. I also want to find out if we can stop extinction, or if extinction is a natural part of species exist ence. Is this a global problem? Many of the endangered species are essential for other species survival, and in the long run, they might even play a big part of the existence of human beings. Every single species on earth is a part of a food chain. The extinction of a species may mean the end of another group of organisms. The eventual extinction of rainforests is a good example of this. The rainforests are a huge part of life on earth as we know it. It is assumed that between 50 and 70 percent of all species on earth are somehow connected to the rainforests, and research shows the rainforests hides millions of species yet to be discovered. Once, the glorious forests covered about 14 percent of the earths surface. Today, we are down to 6 percent, and it is decreasing by more than 6000 square metres every single day. This is not only a huge crisis for the wild life in the rainforests (research shows that nearly 150 species disappear every day because of the deforestation), but through the photosynthesis process, the rainforests are responsible for 28 percent of the earths oxygen turnover. This, combined with the heavy increase in the worlds population, might turn out to be a major problem. Additionally, by tearing down the rainforests, we might miss the cure for several deceases, considering that more than 25 percent of all natural medicines ever discovered, have their roots in the rainforests. We can assume that the last few remaining rainforests will be wiped of the face of the earth within 40 years. Extinction in general. The term extinction is used when a species reaches its end of existence. An estimated 99,9 percent of every species of animals and plants ever to have existed on our planet, are now extinct, and according to an environmental article in The Independant, scientists claim that about 50 percent of all existing species today will be extinct by the 22nd century. Most extinction happens before a race is even discovered. The definition extinction is used about a species when there are no more surviving members of the species that can reproduce, to create another generation of said species. Today, the group of extinct animals increases rapidly every day. According to a recent survey by the American Museum of Natural History, 70 percent thinks that this mass extinction is an even greater threat to our existence than climate changes. Most scientists also believe that the mass extinction and its consequences are greatly underestimated, and needs to be dealt with. Endangered species: According to the International Union for Conservation of Nature, about 40 percent of every living organism on our planet is threatened with extinction. This, of course, only includes the little percentage of species discovered. There are different grades of endangerment, according to the IUCN Red List of endangered species, the first being Least Concern. This means the species faces no current threat of extinction. Some examples are the common mouse and the wood pigeon. Next category is Near threatened, and includes animals such as the tiger shark and the solitary eagle. These species may be threatened by extinction soon. The third category is called Conservation dependent. Some species under this category are the spotted hyena and the killer whale, and they are not critically endangered, but conservation programs are required . Vulnerable is the fourth grade, and these species, including the komodo dragon and the polar bear, are currently facing a risk of becoming extinct. The blue whale and the giant panda are species categorised as Endangered, and are in near future facing a great risk of becoming extinct. The species under the category Critically Endangered are facing an extreme risk of becoming extinct in near future. A species in this group is the mountain gorilla. Extinct in the wild is the category with species where only members of the species in captivation exist. The last category is Extinct, and the species under this category have reached theyre end of existence. There are no living individuals of the species. The Extinct category includes the dodo, the mammoth and more recently, the Baiji river dolphin (the species was declared extinct in 2006) and the West-African black rhinoceros (declared extinct in 2006). Why and how does a species get extinct? There are several ways for a species to get extinct. One way for a species to get extinct is if a species in its food chain faces extinction. For example, in a specific forest, the fox, the rabbit and the grass may be a part of a food chain, where the main part of the foxs diet consists of rabbits, which main diet consists of grass. If one year, the amount of grass is lower than usual, the rabbits may be failing in numbers as well, due to lack of food, and this could lead to that the amount foxes will decrease as well, because they will have a smaller amount of rabbits to feed on. In this scenario, the fox would probably go ahead and find another main source of food, but lets say the food chain is to only consist of these three species. The next year, because the amount of rabbits being eaten by foxes is lower, because the foxes didnt have as much food as usual, and the number of foxes is lower than usual, there would be an increase in the stock of rabbits. The next year again, the n umber of foxes would increase, because there is more rabbits to feed on. And like this, the food chain runs in a loop. This shows that all species depend on each other, and the amount of one species depends on the amount of another species. Climate changes are another reason for animal extinction, and the main reason for the growing concern of the polar bears existence. According to this article from a Norwegian online newspaper, the polar bears are forced to swim much longer distances than before, because of the melting of the Arctic ice. This is a huge problem for the polar bear cubs, which simply are born with a layer of fat to thin to survive for long in the ice-cold water. The melting of the ice also means it is increasingly more difficult for the polar bears to find food. Another reason for species extinction is human interaction. The dodo and the West-African black rhinoceros are great examples of this. The dodo was first seen in the early 1600s when Dutch sailors discovered the island Mauritius. The dodo had stubby wings, and was heavy and slow, an easy target for hungry Dutchmen. In less than 80 years, the dodo was extinct. The sailors who ate them and the fact that their nests were destroyed by rodents the sailors had brought with them. The West-African black rhinoceros horn was believed to be a form for aphrodisiac in parts of Yemen and China, so the species was a popular target for hunters. The species was declared extinct, when conservationists where unable to find any remaining individuals, in 2006. Conclusion. I believe there is no way for us people to stop extinction caused by natural changes, as it is a natural part of a species existence. However, endangered species caused by human actions, such as species being hunted for a part of the animal, like elephants tusks, sharks fins and rhinoceros horns is possible to stop by refuse to support these actions. The same is for the destruction of the rainforests, which I believe we need to do something about. Species extinction caused by climate changes, on the other hand, I dont think we are going to be able to stop. We cant undo whatever damage we have already caused our planet. If the climate changes turns out to be a part of human actions though, we may be able to stop future extinctions caused by changes in the climate.

Geometrical Application Of Ordinary Differential Equation

Geometrical Application Of Ordinary Differential Equation Many practical problems in science and engineering are formulated by finding how one quantity is related to, or depends upon, one or more (other) quantities defined In the problem. Often, it is easier to model a relation between the rates of changes in the variable rather than between the variables themselves. This study of this relationship gives rise to differential equation. Derivatives can always be interpreted as rate. For example, if x is a function of t then dx/dt is the rate of x with respect to t. if x denotes the displacement of a particle, then dx/dt represents the velocity of the particle. If x represents the electric charge then dx/dt represents the flow of charge that is the current. Derivatives of higher orders represents rate of rates. If x denotes the displacement of particle, then d2x/dt2 represents the accelerations. A differential equation can be defined as an equation containing derivatives of various orders and variables .differential equation which involves one independent variable are called ordinary differential equation. If the differential equation involves more than one independent variable and partial derivatives of the dependent variable with respect to them, than it is called partial differential equation. Explanation:- Let y be the dependent variable and x be the independent variable. So the system can be denoted as dy/dx= y , d2y/dx2=y Some Example of Ordinary Differential equation y=62 y+16y =2x x2y-xy+6y=log x yy+ y2 = x2 Introduction to differential equation, and solving linear differential equations using operator method:- In this Term paper, I will first introduce what differential equation is? Separable first order differential equation will be solved. Then the integrating factor will be taught to solve linear differential equation of the first degree. The auxiliary equation (or characteristic equation) will be introduced to solve homogeneous linear equations, and then operator method will be taught finally to solve non-homogeneous linear equations. This term paper assumes readers familiar with basic of calculus, like differentiation and integration. What is differential equation? A differential equation is an equation which contains derivatives. Here are some examples: In these equations, y is an unknown function depends on x which we would like to solve. These kind of equations are very important in different fields, like in chemistry describing rate of reaction, physics describing equation of motion, etc. Therefore, able to solve these equations analytically enables us to understand many natural process. The above equations are known as ordinary differential equations(ODE) since they only contain derivatives with respect to one variable, x. (note that the equations hold for all values of x) In mathematics, an ordinary differential equation (or ODE) is a relation that contains functions of only one independent variable, and one or more of their derivatives with respect to that variable. A simple example is Newtons second law of motion, which leads to the differential equation for the motion of a particle of constant mass m. In general, the force F depends upon the position x(t) of the particle at time t, and thus the unknown function x(t) appears on both sides of the differential equation, as is indicated in the notation F(x(t)). Ordinary differential equations are distinguished from partial differential equations, which involve partial derivatives of functions of several variables. Ordinary differential equations arise in many different contexts including geometry, mechanics, astronomy and population modelling. Many famous mathematicians have studied differential equations and contributed to the field, including Newton, Leibniz, the Bernoulli family, Riccati, Clairaut, dAlembert and Euler. Much study has been devoted to the solution of ordinary differential equations. In the case where the equation is linear, it can be solved by analytical methods. Unfortunately, most of the interesting differential equations are non-linear and, with a few exceptions, cannot be solved exactly. Approximate solutions are arrived at using computer approximations. The trajectory of a projectile launched from a cannon follows a curve determined by an ordinary differential equation that is derived from Newtons second law. Ordinary differential equation Let y be an unknown function in x with y(n) the nth derivative of y, and let F be a given function then an equation of the form is called an ordinary differential equation (ODE) of order n. If y is an unknown vector valued function , it is called a system of ordinary differential equations of dimension m (in this case, F : à ¢Ã¢â‚¬Å¾Ã‚ mn+1à ¢Ã¢â‚¬  Ã¢â‚¬â„¢ à ¢Ã¢â‚¬Å¾Ã‚ m). More generally, an implicit ordinary differential equation of order n has the form where F : à ¢Ã¢â‚¬Å¾Ã‚ n+2à ¢Ã¢â‚¬  Ã¢â‚¬â„¢ à ¢Ã¢â‚¬Å¾Ã‚  depends on y(n). To distinguish the above case from this one, an equation of the form is called an explicit differential equation. A differential equation not depending on x is called autonomous. A differential equation is said to be linear if F can be written as a linear combination of the derivatives of y together with a constant term, all possibly depending on x: with ai(x) and r(x) continuous functions in x. The function r(x) is called the source term; if r(x)=0 then the linear differential equation is called homogeneous, otherwise it is called non-homogeneous or inhomogeneous. Solutions Given a differential equation a function u: I à ¢Ã…  Ã¢â‚¬Å¡ R à ¢Ã¢â‚¬  Ã¢â‚¬â„¢ R is called the solution or integral curve for F, if u is n-times differentiable on I, and Given two solutions u: J à ¢Ã…  Ã¢â‚¬Å¡ R à ¢Ã¢â‚¬  Ã¢â‚¬â„¢ R and v: I à ¢Ã…  Ã¢â‚¬Å¡ R à ¢Ã¢â‚¬  Ã¢â‚¬â„¢ R, u is called an extension of v if I à ¢Ã…  Ã¢â‚¬Å¡ J and A solution which has no extension is called a global solution. Terminology Partial differential equations These are equations which involves more than one independent variable. For instance: Partial differential equations(PDE) are significantly more difficult than ODE, and we wont talk about it at this moment. Order Order of a differential equations is the order of the highest derivative in the equation. Order 1: Order 2: Degree The degree of a differential equation is the degree of the highest derivative in the equation. Degree 1: Degree 2: Separable 1st order ODE If the ODE is in the following form, the solution can be found using integration easily: Example:- In the study of partial differentiation, recall that a function of two variables that equals a constant, describes the points in the 3-D plane with the same potential; . The curves that connect the points with the same potential are called level curves and have the value of c. A contour map is a level curve graph where common elevations are connected giving a 2-D representation of a 3-D reality. Using a LiveMath 3-D graph theory you can plot such a function along with the level curves describing the contours associated with that function. The picture below uses the following function to demonstrate this (here is a LiveMath plug-in animation of the graph below). In general terms, this type of equation is represented by the following: It describes the level curves and is the solution to the following differential equation. The equation below is just the total derivative of the function above. Because it is the total derivative of some function z(x,y) it is called an Exact Differential Equation. To help understand how to solve these types of equations you will look at the solution first and then analyze how to back into that solution. In this example you will take the total derivative of a function and analyze its parts. Then you will take this new equation (a differential equation now) and, knowing the answer, describe the method used to solve it. Input the following equation: To take a total derivative in LiveMath, first input the differential operator d times z (d*z). Input this into a second Prop and substitute the equation into it. Collect common terms on the RHS and Expand the coefficients of the differentials for the final answer. After setting the RHS equal to zero you will have a differential equation to solve. Notice how the coefficients are neither separable, homogeneous, nor are they linear. To help analyze this equation, label the coefficient of dx as M and the coefficient of dy as N. Both are functions of x and y so place the equation in the following form. The total derivative of a function is obtained by adding the partial derivatives of the coefficients. This is done with the equation below. Set up our notebook in the following manner: Perform the substitutions to give the partial derivatives. we can see that differential equations of this type are Exact. They are immediate derivatives of another function. You know this is true in this example because you developed the equation below by taking the derivative of the original function. we can describe an Exact Differential Equation as an equation whose dx coefficient is the partial derivative with respect to x of some function f(x,y) and whose dy coefficient is the partial derivative with respect to y of the SAME function. Since you dry-labed the last example you know what this equation, z=f(x,y), is. This will not be the case as you look to solve these problems though, so you need to find a way of determining that an equation is exact, then you will know that M and N are related to the solution equation in this way! Using the fact that these partial derivatives are of the same function will be the key to the method used to solve these equations. To test a differential equation for exactness, follow the method described in the next example. Test for Exactness This example demonstrates the test for exactness of the same equation used in the previous example. First input the differential equation as shown below. Remember to include an Independence Declaration inside the same case theory the test is performed. To test for exactness, equate the partial derivative with respect to y of M and the partial derivative with respect to x of N. Notice that these partials are with respect to the exact opposite variables as those used to determine the total derivative in the last example. The reason for this will become clear to you later when you derive this test. Set up the partial derivatives and solve by substituting M and N into the partial derivative Ops. The fact that they are equal means that the differential equation is exact! Method of Solution: To solve these types of equations you will need to take one or the other coefficient and go backwards to determine the solution. You can take either M or N to do this, it is up to you. For this example try using M. Solution Method First, set up an equation equating the unknown function, named , to an integral of M plus some unknown function of y. Call this function u for the time being. The reason you do this is the fact that to get M, the partial derivative was taken of the unknown function with respect to x. You will try to back into the answer by integrating M. This is not automatic though, because of the fact that when a partial derivative is performed, one of the variables is treated as a constant and therefore drops out (the derivative of a constant is = 0). Below this derivative is displayed again. We will not get back the function by integrating M, because the y term is not there! It is the constant, as is shown below where you try to get the function back by integrating M. This is very close to the answer, and with a little twist, will lead to a method that you will use to obtain the solution. Input the following props and perform the substitutions as shown. The user defined variable u is used in this case, rather than the arbitrary constant c, because you are actually looking for, what you might call, an arbitrary function. It will also be necessary later to have u defined as a variable for LiveMath to solve for the function. Now we have a potential function (), that represents the solution to the problem. To solve, the function u must be determined. If you take the partial derivative of the unknown function with respect to y this time, you will get N. By setting up the equation this way, you can then isolate u. You already know what N is, so: Next substitute the potential function into the Prop and solve for u by performing an integration. The final solution is achieved by substituting this u Prop back into the function . Since this function describes level curves, it is set equal to a constant c. The question remains, why do you take partial derivatives of M and N to determine if an equation is exact? M and N have been defined as the partial derivatives of z with respect to x and y respectively. By taking the second partial derivative of each coefficient WITH RESPECT TO THE OPPOSITE VARIABLE, the LHS of both of these equations is equal and therefore the RHS are equal too.

The Stoics and Socrates :: essays research papers

The Stoics and Socrates The question of the reality of the soul and its distinction from the body is among the most important problems of philosophy, for with it is bound up the doctrine of a future life. The soul may be defined as the ultimate internal principle by which we think, feel, and will, and by which our bodies are animated. The term "mind" usually denotes this principle as the subject of our conscious states, while "soul" denotes the source of our vegetative activities as well. If there is life after death, the agent of our vital activities must be capable of an existence separate from the body. The belief in an active principle in some sense distinct from the body is inference from the observed facts of life. The lowest savages arrive at the concept of the soul almost without reflection, certainly without any severe mental effort. The mysteries of birth and death, the lapse of conscious life during sleep, even the most common operations of imagination and memory, which abstract a man from his bodily presence even while awake; all such facts suggest the existence of something besides the visible organism. An existence not entirely defined by the material and to a large extent independent of it, leading a life of its own. In the psychology of the savage, the soul is often represented as actually migrating to and fro during dreams and trances, and after death haunting the neighborhood of its body. Nearly always it is figured as something extremely volatile, a perfume or a breath. In Greece, the heartland of our ancient philosophers, the first essays of philosophy took a positive and somewhat materialistic direction, inherited from the pre-philosophic age, from Homer and the early Greek religion. In Homer, while the distinction of soul and body is recognized, the soul is hardly conceived as possessing a substantial existence of its own. Severed from the body, it is a mere shadow, incapable of energetic life. Other philosophers described the soul's nature in terms of substance. Anaximander gives it an aeriform constitution, Heraclitus describes it as a fire. The fundamental thought is the same. The soul is the nourishing agent which imparts heat, life, sense, and intelligence to all things in their several degrees and kinds. The Pythagoreans taught that the soul is a harmony, its essence consisting in those perfect mathematical ratios which are the law of the universe and the music of the heavenly spheres. All these early theories were cosmological rather than psychological in character. Theology, physics, and mental science were not as yet distinguished. In the "Timaeus" (p.

The Small Business Administration (SBA) Essay -- GCSE Business Marketi

The Small Business Administration (SBA) In July of 1953 the United States Congress amended an act called the Small Business Act. Many believed that the essence of the American economic system of private enterprise is free competition. Also, that only through full and free competition can free markets, free entry into business, and opportunities for expression and growth of personal initiative and individual judgment can be assured. Thus, the Small Business Act was amended. In order to carry out the policies of this Act there was hereby created an agency under the name "Small Business Administration". The United States Small Business Administration, more commonly known as the SBA, is a federal agency to protect and assist America's greatest resource, the small business. Since American enterprise is the backbone of our economy and the driving force behind economic growth and prosperity. ?The mission of the Small Business Administration (SBA) is to maintain and strengthen the Nation's economy by aiding, counseling, assisting, and protecting the interests of small businesses and by helping businesses and families recover from disasters.? The SBA's mission is to create economic development through small businesses. To put it in simple terms, the SBA helps businesses get started and helps established businesses grow. The SBA has many functions; here we discuss the six of the functions that small businesses should look at. The first function of the SBA is Business Development, based on management assistance through information, counseling, training and conferences, utilizing the following programs: Â · Services Corps of Retired Executives (SCORE) Â · Small Business Institutes (SBI) Â · Small Business Development Centers (SBDC) Â · ... ...er loans are primarily to help homeowners, renters, and businesses of all sizes for rebuilding there disrupted home or business. When the natural disaster victims need to barrow money to rebuild uninsured damages, it is a good way to go, when you go to the SBA because of the low interest rates, and long-term availability from the SBA. The key things about the loans are that they fix them to your economic standing. Since the SBA was implemented in 1953 the disaster loan assistance program has approved 1.14 million loans and has loaned out more than 16 billion dollars. The SBA has four distinct offices that deal with disaster loans and they are located in Sacramento California, Atlanta Georgia, Ft. Worth Texas, and Niagara Falls New York. The offices are located in very distinct areas of concentration. Due to the fact of geographical storms or natural disasters.