Search results for: risk zones.

Authors: Khalid Khan, Atique Ahmad Zafar, Mohammed A. Alnuem, Hashim Khan

Abstract:

Global Software Development (GSD) projects are passing through different boundaries of a company, country and even in other continents where time zone differs between both sites. Beside many benefits of such development, research declared plenty of negative impacts on these GSD projects. It is important to understand problems which may lie during the execution of GSD project with different time zones. This research project discussed and provided different issues related to time delays in GSD projects. In this paper, authors investigated some of the time delay factors which usually lie in GSD projects with different time zones. This investigation is done through systematic review of literature. Furthermore, the practices to overcome these delay factors which have already been reported in literature and GSD organizations are also explored through literature survey and case studies.

Keywords: Case Studies, Global Software Development, Global Software Engineering, Temporal Difference, Time Delay

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Authors: S. A. Nta

Abstract:

Application of health risk assessment methods is important in order to comprehend the risk of human exposure to heavy metals and other dangerous pollutants. Four soil samples were collected at distances of 10, 20, 30 m and the control 100 m away from the dump site at depths of 0.3, 0.6 and 0.9 m. The collected soil samples were examined for Zn, Cu, Pb, Cd and Ni using standard methods. The health risks via the main pathways of human exposure to heavy metal were detected using relevant standard equations. Hazard quotient was calculated to determine non-carcinogenic health risk for each individual heavy metal. Life time cancer risk was calculated to determine the cumulative life cancer rating for each exposure pathway. The estimated health risk values for adults and children were generally lower than the reference dose. The calculated hazard quotient for the ingestion, inhalation and dermal contact pathways were less than unity. This means that there is no detrimental concern to the health on human exposure to heavy metals in contaminated soil. The life time cancer risk 5.4 × 10^-2 was higher than the acceptable threshold value of 1 × 10^-4 which is reflected to have significant health effects on human exposure to heavy metals in contaminated soil. Good hygienic practices are recommended to ease the potential risk to children and adult who are exposed to contaminated soils. Also, the local authorities should be made aware of such health risks for the purpose of planning the management strategy accordingly.

Keywords: Health risk assessment, pollution, heavy metals, soil.

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Authors: Dmytro Ostroushko, Karel Saksl, Carsten Siemers, Zuzana Rihova

Abstract:

Titanium alloys like Ti-6Al-2Sn-4Zr-6Mo (Ti- 6246) are widely used in aerospace applications. Component manufacturing, however, is difficult and expensive as their machinability is extremely poor. A thorough understanding of the chip formation process is needed to improve related metal cutting operations.In the current study, orthogonal cutting experiments have been performed and theresulting chips were analyzed by optical microscopy and scanning electron microscopy.Chips from aTi- 6246ingot were produced at different cutting speeds and cutting depths. During the experiments, depending of the cutting conditions, continuous or segmented chips were formed. Narrow, highly deformed and grain oriented zones, the so-called shear zone, separated individual segments. Different material properties have been measured in the shear zones and the segments.

Keywords: Titanium alloy, Ti-6246, chip formation, machining, shear zone, microstructure

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Authors: Mayank Singh, O. P. Singh ‘Vatsa’, M. P. Singh

Abstract:

Present paper deals with an evaluation of magnitude of changes in biomass and net primary productivity at ‘Gujar Tal’ sloppy lake margin at Jaunpur in tropical semi-arid region of eastern U.P. (India). The study site abandoned or neglected lands (50 ×125 m) was divided into two zones, i.e. upper zone (up-land) and lower zone (low-land). Maximum biomass in the upper zone of dominant weed Desmostachya bipinnata (L.) Stapf. was 207.47 g m-2 and ‘rest weeds’ was 457.45 g m-2 both in the month of September. In contrast, the peak biomass value in the lower zone of dominant weed Oryza rufipogon Griff. was 1571.44 g m-2 in October and ‘rest weeds’ 270.65 g m-2 in February. Among the two zones, the peak total community biomass was observed 1655.62 g m-2 (October) in the lower zone while its peak value for the upper zone 457.45 g m-2 (September) was comparatively low. Maximum percentage contribution of dominant weeds (D. bipinnata and O. rufipogon) in the respective upper and lower zones and ‘rest weeds’ in both the zones varied in different months in the total community biomass. The peak net primary productivity of dominant weed (D. bipinnata) was 2.09g m-2 day-1 (September) and ‘rest weeds’ was 2.37 g m-2 day-1 (August) in the upper zone, while the lower zone for O. rufipogon was 5.25 g m-2 day-1 (June) as this zone was inundated later and ‘rest weeds’ was 2.08 g m-2 day-1 (January, 2009). The annual net production of total community at site I was highest, 409.58 g m-2 yr-1 in the upper zone followed by 395.58 g m-2 per eight month in the lower zone as this zone was flooded with water during rainy season. The site significance of variations in biomass in relation to plant species was tested by analysis of variance. It was significant between months in all the two zones (p<0.01 and p<0.05).

Keywords: Biomass, Neglected Lake Margin, Productivity, Vegetation.

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Authors: Piotr Prewysz-Kwinto

Abstract:

The market of financial instruments with high risk is developing very dynamically in recent years and attracts more and more interest of investors. It consists essentially of two groups of instruments, i.e. derivatives and exchange traded product (ETP), and each year new types are introduced and offered to investors. The aim of this paper is to present the principles concerning financial instruments with high investment risk available on the Warsaw Stock Exchange (WSE), because they have quite complex constructions, and to evaluate the development of this market. In order to achieve this aim, statistical data from 2014-2016 was analyzed. The results confirm that the financial instruments with high investment risk available on the WSE constitute a diversified and the most numerous group of financial instruments and attract the most interest of investors. Responsible investing requires, however, a good knowledge of how they work and how they can generate profit to not expose oneself to unexpected losses.

Keywords: Derivatives, exchange traded products, financial instruments, financial market, risk, stock exchange.

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Authors: Mojtaba Rezaei, Elham Heydari

Abstract:

This paper highlights the empirical results of analyzing the correlation between accounting information and systematic risk. This association is analyzed among financial ratios and systematic risk by considering the financial statement of 39 companies listed on the Tehran Stock Exchange (TSE) for five years (2014-2018). Financial ratios have been categorized into four groups and to describe the special features, as representative of accounting information we selected: Return on Asset (ROA), Debt Ratio (Total Debt to Total Asset), Current Ratio (current assets to current debt), Asset Turnover (Net sales to Total assets), and Total Assets. The hypotheses were tested through simple and multiple linear regression and T-student test. The findings illustrate that there is no significant relationship between accounting information and market risk. This indicates that in the selected sample, historical accounting information does not fully reflect the price of stocks.

Keywords: Accounting information, market risk, systematic risk, efficient market hypothesis, EMH, Tehran Stock Exchange, TSE.

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Authors: Siavash Asadi Ghajarloo

Abstract:

Nowadays predicting political risk level of country has become a critical issue for investors who intend to achieve accurate information concerning stability of the business environments. Since, most of the times investors are layman and nonprofessional IT personnel; this paper aims to propose a framework named GECR in order to help nonexpert persons to discover political risk stability across time based on the political news and events. To achieve this goal, the Bayesian Networks approach was utilized for 186 political news of Pakistan as sample dataset. Bayesian Networks as an artificial intelligence approach has been employed in presented framework, since this is a powerful technique that can be applied to model uncertain domains. The results showed that our framework along with Bayesian Networks as decision support tool, predicted the political risk level with a high degree of accuracy.

Keywords: Bayesian Networks, Data mining, GECRframework, Predicting political risk.

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Authors: Sung-Hun Lee, Yun-Seong Lee, Jin-O Kim

Abstract:

Reliability Centered Maintenance(RCM) is one of most widely used methods in the modern power system to schedule a maintenance cycle and determine the priority of inspection. In order to apply the RCM method to the Smart Grid, a precedence study for the new structure of rearranged system should be performed due to introduction of additional installation such as renewable and sustainable energy resources, energy storage devices and advanced metering infrastructure. This paper proposes a new method to evaluate the priority of maintenance and inspection of the power system facilities in the Smart Grid using the Risk Priority Number. In order to calculate that risk index, it is required that the reliability block diagram should be analyzed for the Smart Grid system. Finally, the feasible technical method is discussed to estimate the risk potential as part of the RCM procedure.

Keywords: Expert System, FMECA, Fuzzy Theory, Reliability Centered Maintenance, Risk Priority Number

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Authors: Badr M. Alshammari, T. Guesmi

Abstract:

This study presents a modified version of the artificial bee colony (ABC) algorithm by including a local search technique for solving the non-convex economic power dispatch problem. The local search step is incorporated at the end of each iteration. Total system losses, valve-point loading effects and prohibited operating zones have been incorporated in the problem formulation. Thus, the problem becomes highly nonlinear and with discontinuous objective function. The proposed technique is validated using an IEEE benchmark system with ten thermal units. Simulation results demonstrate that the proposed optimization algorithm has better convergence characteristics in comparison with the original ABC algorithm.

Keywords: Economic power dispatch, artificial bee colony, valve-point loading effects, prohibited operating zones.

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Authors: Isabela Moreira Queiroz

Abstract:

Slope stability analyses are largely carried out by deterministic methods and evaluated through a single security factor. Although it is known that the geotechnical parameters can present great dispersal, such analyses are considered fixed and known. The probabilistic methods, in turn, incorporate the variability of input key parameters (random variables), resulting in a range of values of safety factors, thus enabling the determination of the probability of failure, which is an essential parameter in the calculation of the risk (probability multiplied by the consequence of the event). Among the probabilistic methods, there are three frequently used methods in geotechnical society: FOSM (First-Order, Second-Moment), Rosenblueth (Point Estimates) and Monte Carlo. This paper presents a comparison between the results from deterministic and probabilistic analyses (FOSM method, Monte Carlo and Rosenblueth) applied to a hypothetical slope. The end was held to evaluate the behavior of the slope and consequent risk analysis, which is used to calculate the risk and analyze their mitigation and control solutions. It can be observed that the results obtained by the three probabilistic methods were quite close. It should be noticed that the calculation of the risk makes it possible to list the priority to the implementation of mitigation measures. Therefore, it is recommended to do a good assessment of the geological-geotechnical model incorporating the uncertainty in viability, design, construction, operation and closure by means of risk management. 

Keywords: Probabilistic methods, risk assessment, risk management, slope stability.

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Authors: Marco Bötel, Tobias Gelau, Wendelin Gross

Abstract:

Supply chain networks are frequently hit by unplanned events which lead to disruptions and cause operational and financial consequences. It is neither possible to avoid disruption risk entirely, nor are network members able to prepare for every possible disruptive event. Therefore a continuity planning should be set up which supports effective operational responses in supply chain networks in times of emergencies. In this research network related degrees of freedom which determine the options for responsive actions are derived from interview data. The findings are further embedded into a common risk management process. The paper provides support for researchers and practitioners to identify the network related options for responsive actions and to determine the need for improving the reaction capabilities.

Keywords: Supply Chain Risk Management, Business Continuity Planning, Degrees of Freedom, Risk Management Process, Mitigation Measures.

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Authors: Anders Troedsson

Abstract:

For us humans, risk and insecurity are intimately linked to vulnerabilities - where there is vulnerability, there is potentially risk and insecurity. Reducing vulnerability through compensatory measures means decreasing the likelihood of a certain external event be qualified as a risk/threat/assault, and thus also means increasing the individual’s sense of security. The paper suggests that a meaningful way to approach the study of risk/ insecurity is to organize thinking about the vulnerabilities that external phenomena evoke in humans as perceived by them. Such phenomena are, through a set of given vulnerabilities, potentially translated into perceptions of "insecurity." An ontological discussion about salient timespace characteristics of external phenomena as perceived by humans, including such which potentially can be qualified as risk/threat/assault, leads to the positing of two dimensions which are central for describing what in the paper is called the essence of risk/threat/assault. As is argued, such modeling helps analysis steer free of the subjective factor which is intimately connected to human perception and which mediates between phenomena “out there” potentially identified as risk/threat/assault, and their translation into an experience of security or insecurity. A proposed set of universally given vulnerabilities are scrutinized with the help of the two dimensions, resulting in a modeling effort featuring four realms of vulnerabilities which together represent a dynamic whole. This model in turn informs modeling on human security.

Keywords: Human vulnerabilities, human security, inert-immediate, material-immaterial, timespace.

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Authors: Chin Wen Cheong

Abstract:

This study employs a bivariate asymmetric GARCH model to reveal the hidden dynamics price changes and volatility among the emerging markets of Thailand and Malaysian after the Asian financial crisis from January 2001 to December 2008. Our results indicated that the equity markets are sharing the common information (shock) that transmitted among each others. These empirical findings are used to demonstrate the importance of shock and volatility dynamic transmissions in the cross-market hedging and market risk.

Keywords: multivariate ARCH, structural change, value at risk.

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Authors: Shaya Alshahrani

Abstract:

Perceived risks play a major role in consumer intentions, behaviors, attitudes, and decisions about online shopping in the KSA. This paper investigates the influence of six perceived risk dimensions on Saudi consumers: product risk, information risk, financial risk, privacy and security risk, delivery risk, and terms and conditions risk empirically. To ensure the success of this study, a random survey was distributed to reflect the consumers’ perceived risk and to enable the generalization of the results. Data were collected from 323 respondents in the Kingdom of Saudi Arabia (KSA): 50 who had never shopped online and 273 who had done so. The results indicated that all six risks influenced the respondents’ perceptions of online shopping. The non-online shoppers perceived financial and delivery risks as the most significant barriers to online shopping. This was followed closely by performance, information, and privacy and security risks. Terms and conditions were perceived as less significant. The online consumers considered delivery and performance risks to be the most significant influences on internet shopping. This was followed closely by information and terms and conditions. Financial and privacy and security risks were perceived as less significant. This paper argues that introducing adequate legal solutions to addressing related problems arising from this study is an urgent need. This may enhance consumer trust in the KSA online market, increase consumers’ intentions regarding online shopping, and improve consumer protection.

Keywords: Perceived risk, consumer protection, online shopping, Saudi Arabia, online contracts, e-commerce.

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Authors: Worachat Wannawong, Usa W. HumphriesPrungchan Wongwises, Suphat Vongvisessomjai

Abstract:

The mathematical modeling of storm surge in sea and coastal regions such as the South China Sea (SCS) and the Gulf of Thailand (GoT) are important to study the typhoon characteristics. The storm surge causes an inundation at a lateral boundary exhibiting in the coastal zones particularly in the GoT and some part of the SCS. The model simulations in the three dimensional primitive equations with a high resolution model are important to protect local properties and human life from the typhoon surges. In the present study, the mathematical modeling is used to simulate the typhoon–induced surges in three case studies of Typhoon Linda 1997. The results of model simulations at the tide gauge stations can describe the characteristics of storm surges at the coastal zones.

Keywords: lateral boundary, mathematical modeling, numericalsimulations, three dimensional primitive equations, storm surge.

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Authors: Mohamed Saad Ahmed Hussien

Abstract:

This paper discusses the risk management in Islamic banks and aims to determine the difference in the practices and methods of risk management in those banks compared to the conventional banks, and to make a case study of the biggest Islamic bank in Egypt (Faisal Islamic Bank of Egypt) to identify the most important financial risks faced and how to manage those risks. It was found that Islamic banks face two types of risks. The first type is similar to the risks in conventional banks; the second type is the additional risks which facing the Islamic banks only as a result of some Islamic modes of financing. With regard to the risk management, Islamic banks such as conventional banks applied the regulatory rules issued by the Central Banks and the Basel Committee; Islamic banks also applied the instructions and procedures issued by the Islamic Financial Services Board (IFSB). Also, Islamic banks are similar to the conventional banks in the practices and methods which they use to manage the risks. And there are some factors that may affect the risk management in Islamic banks, such as the size of the bank and the efficiency of the administration and the staff of the bank.

Keywords: Conventional banks, Faisal Islamic Bank of Egypt, Islamic banks, risk management.

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Authors: Taner Ersoz, Filiz Ersoz, Seyma Ozbilge

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In this study, the clients who applied to a bank branch for loan were analyzed through data mining. The study was composed of the information such as amounts of loans received by personal and SME clients working with the bank branch, installment numbers, number of delays in loan installments, payments available in other banks and number of banks to which they are in debt between 2010 and 2013. The client risk profile was examined through Classification and Regression Tree (CART) analysis, one of the decision tree classification methods. At the end of the study, 5 different types of customers have been determined on the decision tree. The classification of these types of customers has been created with the rating of those posing a risk for the bank branch and the customers have been classified according to the risk ratings.

Keywords: Client classification, loan suitability, risk rating, CART analysis, decision tree.

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Authors: P. Pongsumpun

Abstract:

The Swine flu outbreak in humans is due to a new strain of influenza A virus subtype H1N1 that derives in part from human influenza, avian influenza, and two separated strains of swine influenza. It can be transmitted from human to human. A mathematical model for the transmission of Swine flu is developed in which the human populations are divided into two classes, the risk and non-risk human classes. Each class is separated into susceptible, exposed, infectious, quarantine and recovered sub-classes. In this paper, we formulate the dynamical model of Swine flu transmission and the repetitive contacts between the people are also considered. We analyze the behavior for the transmission of this disease. The Threshold condition of this disease is found and numerical results are shown to confirm our theoretical predictions.

Keywords: Mathematical model, Steady state, Swine flu, threshold condition.

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Authors: D. Jakovčević, M. Mihelja Žaja

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The purpose of this paper is to analyze the influence and relative share of underwriting risks in explaining the variation in insurance cycles in subsequent periods. Through the insurance contracts they underwrite, insurance companies assume risks. Underwriting risks include pricing risk, reserve risk, reinsurance risk and occurrence risk. These risks pose major risks for property and liability insurers, and therefore their impact on the insurance cycle is important. The main goal of this paper is to determine the relative proportion of underwriting risks in explaining the variation of insurance cycle. In order to fulfill the main goal of the paper vector autoregressive model, VAR, will be applied.

Keywords: Insurance cycle, insurance risks, combined ratio, Republic of Croatia.

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Authors: M. S. Kaiser

Abstract:

An attempt has been made to determine the strength and impact properties of Cr-Mo steel weld and base materials by varying the current during manual metal arc welding. Toughness over a temperature range from -32 to 100°C of base, heat affected zone (HAZ) and weld zones at three current settings are made. It is observed that the deterioration in notch toughness at any zone with the temperature decreases. The values of notch toughness for all zones at -32°C are almost same for any current settings. The values of notch toughness at HAZ area are higher than that of weld area due to the coarsening of ferrite grain of HAZ occurs with higher heat input. From microhardness and microstructure result, it can be concluded that large inclusion content in weld deposit is the cause of lower notch toughness value.

Keywords: Chromium-Molybdenum steel, post-weld heat treatment, heat affected zone, microstructure.

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Authors: J. R. Wang, W. Y. Cheng, J. S. Yeh, S. W. Chen, Y. M. Ferng, J. H. Yang, W. S. Hsu, C. Shih

Abstract:

To understand the risk for dry storage concrete casks in the cask loading, transfer, and storage phase, the purpose of this research is to establish the probabilistic risk assessment (PRA) analysis methodology for dry storage concrete casks by using SAPHIRE 8 code. This analysis methodology is used to perform the study of Taiwan nuclear power plants (NPPs) dry storage system. The process of research has three steps. First, the data of the concrete casks and Taiwan NPPs are collected. Second, the PRA analysis methodology is developed by using SAPHIRE 8. Third, the PRA analysis is performed by using this methodology. According to the analysis results, the maximum risk is the multipurpose canister (MPC) drop case.

Keywords: PRA, Dry storage, concrete cask, SAPHIRE.

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Authors: Mohsen Shirani, Micaela Demichela

Abstract:

During the last decades, a number of food crises such as Bovine Spongiform Encephalopathy (BSE), Mad-Cow disease, Dioxin in chicken food, Food-and-Mouth Disease (FMD), have certainly inflected the reliability of the food industry. Consequently, the trend in applying different scientific methods of risk assessment in food safety has obtained more attentions in the academic and practice. However, lack of practical approach considering entire food supply chain is tangible in the academic literature. In this regard, this paper aims to apply risk assessment tool (FMEA) with integration of Human Factor along the entire supply chain of food production and test the method in a case study of Diary production, and analyze its results.

Keywords: Food Risk Assessment, FMEA, Human Factor.

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Authors: Frantisek Bozek, Alexandr Bozek, Eduard Bakos, Jiri Dvorak, Alena Bumbova, Lenka Jesonkova

Abstract:

The case study deals with the semi-quantitative risk assessment of water resource earmarked for the emergency supply of population with drinking water. The risk analysis has been based on previously identified hazards/sensitivities of the elements of hydrogeological structure and technological equipment of ground water resource as well as on the assessment of the levels of hazard, sensitivity and criticality of individual resource elements in the form of point indexes. The following potential sources of hazard have been considered: natural disasters caused by atmospheric and geological changes, technological hazards, and environmental burdens. The risk analysis has proved that the assessed risks are acceptable and the water resource may be integrated into a crisis plan of a given region.

Keywords: Crisis, emergency, frequency, ground water, hazard, point index, risk, sensitivity, water supply.

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Authors: Yu-Chen Lin, Tzong-Yeang Lee

Abstract:

This study aims to assess the vulnerability and risk of the coastal areas of Taijiang to abnormal oceanographic phenomena. In addition, this study aims to investigate and collect data regarding the disaster losses, land utilization, and other social, economic, and environmental issues in these coastal areas to construct a coastal vulnerability and risk map based on the obtained climate-change risk assessment results. Considering the indexes of the three coastal vulnerability dimensions, namely, man-made facilities, environmental geography, and social economy, this study adopted the equal weighting process and Analytic Hierarchy Process to analyze the vulnerability of these coastal areas to disasters caused by climatic changes. Among the areas with high coastal vulnerability to climatic changes, three towns had the highest coastal vulnerability and four had the highest relative vulnerability. Areas with lower disaster risks were found to be increasingly vulnerable to disasters caused by climatic changes as time progresses.

Keywords: Climate change, coastal disaster, risk, vulnerability

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Authors: M. Shahrokhi, F. Rostami, M.A. Md Said, S. Syafalni

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It is essential to have a uniform and calm flow field for a settling tank to have high performance. In general, the recirculation zones always occurred in sedimentation tanks. The presence of these regions may have different effects. The nonuniformity of the velocity field, the short-circuiting at the surface and the motion of the jet at the bed of the tank that occurs because of the recirculation in the sedimentation layer, are affected by the geometry of the tank. There are some ways to decrease the size of these dead zones, which would increase the performance. One of the ways is to use a suitable baffle configuration. In this study, the presence of baffle with different position has been investigated by a finite volume method, with VOF (Volume of Fluid) model. Besides, the k-ε turbulence model is used in the numerical calculations. The results indicate that the best position of the baffle is obtained when the volume of the recirculation region is minimized or is divided to smaller part and the flow field trend to be uniform in the settling zone.

Keywords: Sedimentation tanks, Baffle, Numerical Modeling, VOF, Circulation Zone

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Authors: Martina Kanciruk, Jac W. Andrews, Tyrone Donnon

Abstract:

The purpose of this study was to determine the significance of history of obesity for the development of childhood overweight and/or obesity. Accordingly, a systematic literature review of English-language studies published from 1980 to 2012 using the following data bases: MEDLINE, PsychINFO, Cochrane Database of Systematic Reviews, and Dissertation Abstracts International was conducted. The following terms were used in the search: pregnancy, overweight, obesity, family history, parents, childhood, risk factors. Eleven studies of family history and obesity conducted in Europe, Asia, North America, and South America met the inclusion criteria. A meta-analysis of these studies indicated that family history of obesity is a significant risk factor of overweight and /or obesity in offspring; risk for offspring overweight and/or obesity associated with family history varies depending of the family members included in the analysis; and when family history of obesity is present, the offspring are at greater risk for developing obesity or overweight. In addition, the results from moderator analyses suggest that part of the heterogeneity discovered between the studies can be explained by the region of world that the study occurred in and the age of the child at the time of weight assessment.

Keywords: Childhood obesity, overweight, family history, risk factors, meta-analysis.

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Authors: Toan Vu Duc, Son Ha Viet

Abstract:

An evaluation of the PCBs residues in the surface soils from Bacninh, Vietnam was carried out. Sixty representative soil samples were collected from the centre of Bacninh and three surrounding districts. The analyzed results indicated the wide extent of contamination of total PCBs in Bacninh. In industrial and urban zones, total PCBs concentrations ranged from ranged from <0.02 to 32.68ng g-1 (mean 19.89 ±15.64ng g-1) dry weight, while those in agricultural zones ranged from <0.02 to 13.26ng g-1 (mean 8.14 ± 4.89ng g-1) dry weight. The mean percentages of PCB28, PCB52, PCB101, PCB138, PCB153 and PCB180 compared with Σ6PCBs in the analyzed soil samples are 3.1%, 13.9%, 21.7%, 30.7%, 25.8% and 4.8%, respectively. These values can be explained by the chemical properties as well as the compositions of PCBs mixture which probably escaped from dielectric oil. An increasing trend and the long-time release of PCBs are observed.

Keywords: Contamination, PCBs, soil, temporal trend.

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Authors: Mahmoud Zarrini

Abstract:

Avalanche release of snow has been modeled in the present studies. Snow is assumed to be represented by semi-solid and the governing equations have been studied from the concept of continuum approach. The dynamical equations have been solved for two different zones [starting zone and track zone] by using appropriate initial and boundary conditions. Effect of density (ρ), Eddy viscosity (η), Slope angle (θ), Slab depth (R) on the flow parameters have been observed in the present studies. Numerical methods have been employed for computing the non linear differential equations. One of the most interesting and fundamental innovation in the present studies is getting initial condition for the computation of velocity by numerical approach. This information of the velocity has obtained through the concept of fracture mechanics applicable to snow. The results on the flow parameters have found to be in qualitative agreement with the published results.

Keywords: Snow avalanche, fracture mechanics, avalanche velocity, avalanche zones.

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Authors: Frantisek Bozek, Alexandr Bozek, Alena Bumbova, Jiri Dvorak, Lenka Jesonkova

Abstract:

The contamination of 15 ground water resources of a selected region earmarked for the emergency supply of population has been monitored. The resources have been selected on the basis of previous assessment of natural conditions and the exploitation of territory in their surroundings and infiltration area. Two resources out of 15 have been excluded from further exploitation, because they have not met some of the 72 assessed hygienic indicators of extended analysis. The remaining 13 resources have been the subject of health risk analysis in relation to the contamination by arsenic, lead, cadmium, mercury, nickel and manganese. The risk analysis proved that all 13 resources meet health standards with regard to the above mentioned purposefully selected elements and may thus be included into crisis plans. Water quality of ground resources may be assessed in the same way with regard to other contaminants.

Keywords: Contamination, drinking water, emergency supply, health risk, hygienic limits, metals, risk assessment.

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Authors: Hatem A. Khater, A. Baith Mohamed, Sara M. Kamel

Abstract:

Software Development Risks Identification (SDRI), using Fault Tree Analysis (FTA), is a proposed technique to identify not only the risk factors but also the causes of the appearance of the risk factors in software development life cycle. The method is based on analyzing the probable causes of software development failures before they become problems and adversely affect a project. It uses Fault tree analysis (FTA) to determine the probability of a particular system level failures that are defined by A Taxonomy for Sources of Software Development Risk to deduce failure analysis in which an undesired state of a system by using Boolean logic to combine a series of lower-level events. The major purpose of this paper is to use the probabilistic calculations of Fault Tree Analysis approach to determine all possible causes that lead to software development risk occurrence

Keywords: Software Development Risks Identification (SDRI), Fault Tree Analysis (FTA), Taxonomy for Software Development Risks (TSDR), Probabilistic Risk Assessment (PRA).

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