Simulating Geobag Revement Failure Processes

An experimental and numerical study has been carried out to help develop design guidelines for the construction of low-cost river bank protection using geobags. Building upon previous work, a 1:10 scale model was tested in a laboratory flume, comparing two different construction methods (running bond and stack bond), subjected to three different water depths. It was found that whilst the failure pattern was highly dependent on water depth, the construction method had no noticeable impact, and it was concluded that the dominating factor is the friction between individual geobags, which itself is dependent on bag overlap rather than specific construction method. A simple Discrete Element Method (DEM) model was constructed using the LIGGGHTS open source software with drag and lift models applied to a multi sphere simulation of the laboratory model geobags. It was found that despite its simplicity this DEM model could reproduce the failure pattern of revetments very well, and thus has potential for future use in developing design guidelines aimed at the developing world

DYNACLIPS (DYNAmic CLIPS): A dynamic knowledge exchange tool for intelligent agents

In a dynamic environment, intelligent agents must be responsive to unanticipated conditions. When such conditions occur, an intelligent agent may have to stop a previously planned and scheduled course of actions and replan, reschedule, start new activities and initiate a new problem solving process to successfully respond to the new conditions. Problems occur when an intelligent agent does not have enough knowledge to properly respond to the new situation. DYNACLIPS is an implementation of a framework for dynamic knowledge exchange among intelligent agents. Each intelligent agent is a CLIPS shell and runs a separate process under SunOS operating system. Intelligent agents can exchange facts, rules, and CLIPS commands at run time. Knowledge exchange among intelligent agents at run times does not effect execution of either sender and receiver intelligent agent. Intelligent agents can keep the knowledge temporarily or permanently. In other words, knowledge exchange among intelligent agents would allow for a form of learning to be accomplished

Paper Session II-B - Simulating Shuttle and Derivative Vehicle Processing at Kennedy Space Center

Rockwell International Space Systems Division is teamed with the University of Central Florida on a research project to develop an automated simulation system to model ground processing scenarios for the Shuttle and Shuttle-derived vehicles. This simulation system is necessary to evaluate launch site facilities requirements and estimate life-cycle costs of future space programs. This paper presents the results of initial simulation modeling of the orbiter processing critical path at Kennedy Space Center (KSC). An approach is presented for the planned capabilities to simulate mixed fleet processing and to perform sensitivity, capacity, cost, and risk analyses. Potential expert system applications for the simulation system are presented, such as a resource allocation tool for standdown periods or a long-range scheduling tool for future programs like the Space Exploration Initiative. The simulation model will be developed using the object-oriented languages MOD SIM II and C+ + . This model is different than other software tools currently used for planning at KSC in that it is stochastic rather than deterministic. A deterministic model assumes all parameters of the model are known constants. A stochastic system defines the operations process using an indexed collection of random variables. The modeling system will be expandable using object-oriented inheritance techniques in which facilities and vehicles are modeled as templates. This system is different from other planning systems used at KSC in that supplemental vehicle and/or facility data can be introduced during program execution. This technique allows effective modeling of dynamic launch site environments for future programs

Simulation of complete geobag revetment failure processes

Geobag revetments have recently emerged as long-term riverbank protection measures in developing countries, however, their performance is still not well understood. According to previous research by Heriot-Watt University and The University of Edinburgh, the initial failure mechanisms associated with simple geobag riverbank revetments are now relatively well understood and numerical modelling has advanced to the stage where incipient failure can be simulated using Discrete Element Modelling (DEM). However, to develop the type of robust design standards needed to improve the effectiveness and durability of geobag installations, the essential next step is to develop numerical techniques to efficiently simulate the complete failure of geobag structures. In order to improve our understanding of geobag–water flow interactions and gather the data required to calibrate and validate the numerical model, a comprehensive programme of small-scale experimental tests was undertaken. Comparison of a range of different construction methods and revetment side slopes subjected to different flow loading was carried out. The results indicate that whilst failure mechanisms are highly dependent on water depth and revetment slope, the construction method had no noticeable impact and it was concluded that the dominating factor is the friction between individual geobags, which itself is dependent on bag overlap rather than specific construction method. Furthermore, flow velocity measurements taken during both the pre-failure and post-failure stages indicated that the formation of failure zones leads to a decrease in turbulence, and a subsequent stabilization of the failure process. In the second part of the research a Discrete Element Method (DEM) model was constructed using the LIGGGHTS open source software with drag and lift models applied to a multi sphere simulation of the laboratory model geobags. The validated DEM model could reproduce very well the complete failure processes of the geobag revetment, mounted on a fixed bed and also on a mobile sediment bed. Finally, it is found that the DEM model could provide more details on the performance of geobag revetment in riverbanks. Based on the results found, it can be concluded that the developed DEM model can satisfactorily simulate the complete failure of geobag revetments and hence be the basis for the development of future deign guides. Finally, recommendations on the application of DEM model for design guidelines of geobag revetment are outlined

Globalization of Culture and Religious Tourism

This study proceeded to examine the relationship between cultural globalization and religious tourism. Giddens and Robertson’s theory was applied to test the research hypotheses. The method is quantitative and required population of study came to be 400 pilgrims of Shah-e-Cheragh Holey Shrine, aged 18-65, randomly selected and analyzed. The data were collected by giving questionnaires, and were analyzed using SPSS software. This study totally involved 5 hypotheses, one of which is rejected. The results indicated that modern info-communicative technology and individualism hold a strongly negative relationship with religious tourism, while awareness against globalization reveals no relationship with religious tourism

Laboratory Investigation of Geobag Revetment Performance in Rivers

Geobag (sand-filled geotextile bags) revetments have recently emerged as long-term riverbank protection measures in developing countries; however, their performance is still not well understood. The hydraulic stability of geobag revetments used for riverbank protection has been studied within an extensive laboratory programme to improve our understanding of the complete failure processes of geobag revetments. A 1:10 scale distorted physical model was tested in a laboratory flume, comparing a range of different construction methods and revetment side slopes, subjected to different flow loading. The results indicate that whilst failure mechanisms are highly dependent on water depth and revetment slope, the construction method had no noticeable impact. It was thus concluded that the dominating factor is the friction between individual geobags, which itself is dependent on bag longitudinal overlap rather than a specific construction method

Investigating the Relationship between Religiosity and Social Hopefulness among Female High-School Students in Shiraz

  Introduction   Religion is an effective factor in socialization process which has attracted the attention of many sociologists. It is an important factor affecting mental health. Religion transforms the world picture in an individual view and changes his perception of himself, creation and the events surrounding him. Such a person does not feel frustration and anxiety caused by difficulties. He is sure that God support him. Incidents and events are transient and patience will be rewarded by God. (Cruise, Abedi, 2008). Naturally, human beings are vulnerable to concerns and worries so they consistently have fought to overcome them. Religiously speaking, one of the objectives of creation of humankind was to bring peace and comfort in life and humans struggle to overcome despair and depression (Parcham and others, 2010). Quality of life has a significant relationship with hope and plays an important role in achieving social success (Snayder quoted in Mehrinejad and Moghaddam, 2011). The lack of hope causes a person to feel disabled and desperate and that he does not have enough self-esteem. We tolerate suffering and torment because we think in the future it changes to the good. Therefore, all our efforts are worthwhile. Hope enables us to resist the difficulties and problems of the present so the door will be opened to solve them (Snyder, 2000). Spiritual crisis is one of the consequences of despair even among some religious people. Appropriate goal setting is a key factor in this battle. It seems that one of the causes of failures and successive wanderings in humans is disappointment in reaching goals and lack of effort. Optimistic people, with more faith, and popularity have more adaptability with education, employment and sports. Also, they have more political and social achievements and happiness. They hope they can live with the challenges that may be encountered consistently. Hope is so important that in recent years a new approach has emerged in the field of psychology, which is known as positive psychology. Positive psychology is the scientific study of human abilities and strengths. One of the most important element of positive psychology is optimism. So this paper aims at considering the relationship between religiosity and social hopefulness.     Materials & Methods   This is an applied research. With regard to the type of study, it is a descriptive study and has used the survey method. The study population consists of all high school female students in Shiraz during the academic year of 1391 -92, whose total number is equal to 5637 individuals. 381 students were selected by use of cluster sampling method and Cochran formula. Data collection techniques in this study was a Likert type questionnaire and the data was analyzed by SPSS software.     Discussion of Results & Conclusions   In this study, emotional, religious, moral and ritual aspects of hope were measured. According to the results of previous research, a positive relationship between religious orientation and hopefulness was found. Likewise, hopelessness is associated with depression. Students who are religious and hopeful, have a higher tolerance threshold and are generally more successful in school.     

Paper Session I-A - Modeling Current and Future Launch Vehicle Processing Using Object-Oriented Simulation Techniques

STARSIM, an acronym for Space Transportation Activities and Resources Simulation, is an objectoriented, menu-driven, user-friendly, decision support system for simulating National Space Transportation System (NSTS) processing, as well as Personnel Launch System (PLS)-National Launch System (NLS), PLS-Proton, PLS-Titan IV, Hermes-Ariane 5 and Cargo Transfer Return Vehicle (CTRV) processing. For each launch system modeled, output is displayed numerically (for global statistical information), in pie chart form (to visualize percentages of subcategories associated with a main category) and in Gantt chart form (for visualizing when and where each launch vehicle experiences waiting, processing, blocking and maintenance periods, and the reasons for blocking). Users may input a comprehensive set of system parameters (e.g., number of launch vehicles, processing times at each facility, number of bays at a particular facility) using a window-based environment, or by supplying an existing input data file. Data for existing launch systems and representative data for proposed systems are used to illustrate output for the models mentioned above. The object-oriented methodology employed in the initial model (i.e., NSTS processing) permitted additional models to be implemented in a minimum amount of time and effort

Paper Session III-B - A Combined Probabilistic and Expert System Approach for Assigning Repair Start-Times at the NASA Shuttle Logistics Depot

The NASA Shuttle Logistics Depot (NSLD) is tasked with the responsibility for repair and manufacture of Line Replaceable Unit (LRU) hardware and components to support the Space Shuttle Orbiter. Due to shrinking budgets, cost effective repair of LRUs becomes a primary objective. To achieve this objective, it is imperative that resources can be assigned to those LRUs which have the greatest expectation of being needed as a spare. Forecasting the times at which spares are needed requires consideration of many significant factors including, for example, failure rate, flight rate, spares availability, and desired level of support, among others. This paper summarizes the results of the research and development work that has been accomplished in producing an automated system for assisting in the assignment of effective repair start-times for LRUs at the NSLD. This system, called the Repair Start-time Assignment System (RSAS), combines probabilistic modeling and expert system technology to generate an expected future need date. The result is a mathematically calculated value that has been adjusted heuristically to produce a date for beginning the repair that has significantly greater confidence (in the sense that a desired probability of support is assured) than dates produced using other techniques. Since an important output of RSAS is the longest repair turn-around time that will ensure a desired probability of support, RSAS has the potential for being applied to operations at any repair depot where spares are on-hand and repair start-times are of interest. In addition, RSAS incorporates tenants of Just-In-Time (JIT) techniques in the connotation that the latest repair start-time (i.e., the latest time at which repair resources must be committed) may be calculated for every failed unit. This could aid in reducing the spares inventory for certain items, without significantly increasing the risk of unsatisfied demand