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Abstract: Radioactive measurements in the decay process of any radioactive sample can be predicted by radioactive-decay law. This predication is based over its average behavior. In actual practice, the radioactive measurements show fluctuations about the average value. For any radioactive sample, there is an exact number which disintegrates in any given unit of time fluctuates around the average value. In counting applications, it is important to estimate this fluctuation because it indicates the repeatability of results of a measurement. This will identify it by using periodogram analysis that depicts the periodicity in the radioactive decay of the given sample of Americium-241. Statistical distributions that the given sample followed with goodness-of-fit tests are examined. Maximum-Likelihood Estimator (MLE) has been used to find the population parameters. The randomness in radioactive decay has been verified by non-parametric method. These statistical analyses are based over the amount of internal fluctuation in the given radioactive source that is consistent with the predictions obtained. These measurements are obtained by measuring the decay of 300 counts per 10 sec. of Americium-241 using a Geiger Muller (GM) Counter in the teaching laboratory, at the Department of Physics, University of Karachi, Karachi, Pakistan. Keywords: Americium-241, Radioactive measurements, Nuclear Statistics, GM counter. |
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Abstract: Risks cannot be entirely removed or eliminated from Human’s life and from lives of Organizations but may be mitigated and their effects may be reduced. The principal objective of this research is to identify and assess supply chain risks in dairy products sector. A set of supply chain risks is identified through extensive literature survey and is divided into five major categories and 28 components through Risk Breakdown Structure approach. A questionnaire is developed based upon these 28 components and data collected from 170 respondents. Risks are assessed through Probability and Impact scores obtained from responses and then slotted into 2x2 Risk Matrix. A risk matrix comprising of 04 quadrants is formulated through low and high scores of probability and impact of all 28 risks. It is found that 16 risks fall in high risk quadrant, 08 in moderate and 04 in low risk quadrant. Risks of competition, deceases, terrorism, quality of raw materials, natural disasters along with those falling high risk quadrants are required to be promptly responded by dairy sector operators for effective risk mitigation. Similarly risk responses have been suggested for moderate and low gravity risks as well. Keywords: Supply Chain Risk Sources, Risk Assessment, Risk Grid, Dairy Sector, Supply Chain Management. |
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Abstract: Most of the runoff in Kunhar Catchment is generated from the snowmelt which makes it more sensitive to climate change. The Snowmelt-Runoff Model (SRM), a simple degree-day model, has been applied around the world under different climatic regions to evaluate the hydrological effects of climate change. The current study encompasses the use of Snowmelt-Runoff Model (SRM) to forecast stream flows in Kunhar river catchment depicting three varying climate change scenarios i.e. a) an increase in +2°C temperature b) an increase in +2°C temperature along with 20% increase in precipitation, and c) a 20% increase in precipitation. The study area was distributed with respect to varying altitude with 500 m elevation interval. Moderate resolution Imaging Satellite (MODIS) daily snow product MOD10A1 is used to map snow cover. SRM model was simulated and later climate change run was evaluated. SRM Model was calibrated for 2003 – 2004 and validated for 2005 – 2006 with an average coefficient of 0.93 R2 and average seasonal volume difference Dv of 1.46%. The stimulated results for scenario “b” show an increase of flow discharge by 27%. Whereas, there was 21% and 6% increment in discharge simulated for scenarios “a” and “c” respectively. Keywords: SRM, Climate Change, Remote Sensing, Hydrology. |
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Abstract: Public services are the active organs of governments facilitating people to a level of comfort. The provision of these services is an essential part for exercising power by a government. Fire protection is also one of the basic public services which plays a significant role in emergencies. Generally, their service brings a relief helping people to come out of a situation of panic and terror. Karachi is a mega city with a population of more than twenty million and about three million households have only twenty two firefighting station set ups, roughly one station to cater to the needs of one million people. This study is a critical evaluation of effectiveness of these services across the city. Slums and high rise structures in the city pose serious problems in the functioning of these services, besides which encroachments along roads, road conditions, lack of protection from law enforcing agencies, low level of awareness of people regarding fire incidence and finally lack of firefighting attributes and government support are the major problems. Keywords: Firefighting services, city structure, buildings, road network, and people’s response. |
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Abstract: Sindh province has diverse agro-climatological regions ranging from irrigated agricultural belt in the middle and desert to the east and bare hilly ranges on the west. Climate of the province is semi-arid with low annual precipitation of around 200mm. Agriculture and agribusiness is the main source of livelihood for majority in the province. Soil moisture study is an important parameter in agriculture, hydrology and hydrometeorology for studies related to sustainable development of agriculture and agribusiness in the province. In agriculture, soil moisture is used to study evapotranspiration, droughts, irrigation scheduling, and crop yield forecasting. It is also important for the environmental studies like subsequent precipitation patterns, temperature change and water quality. Soil moisture plays an important role in hydrology e.g., flood control, soil erosion and slope failure, reservoir management, geotechnical engineering and runoff generation. Due to synoptic coverage and high temporal resolution satellite remote sensing is ideal for instantaneous measurement of soil moisture content and its spatial and temporal behavior. In this study soil moisture at province level has been mapped through Advanced Microwave Scanning Radiometer (AMSR-E) and Moderate Resolution Imaging Spector Radiometer (MODIS) for the years 2007 and 2010. As 2007 was as normal year while 2010 was a wet year due to heavy rainfall and flood in the province, both the years have been selected to study soil moisture anomalies in normal and wet seasons. The results of MODIS derived soil moisture is in moderate agreement with AMSR-E soil moisture product proving the effectiveness of high resolution products in optical range. Keywords: Soil Moisture, MODIS, AMSR-E, Agriculture, Remote Sensing, Hydrology. |