141 research outputs found

    A Survey of Systems Engineering Effectiveness - Initial Results

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    This survey quantifies the relationship between the application of Systems Engineering (SE) best practices to projects and programs, and the performance of those projects and programs. The survey population consisted of projects and programs executed by defense contractors who are members of the Systems Engineering Division (SED) of the National Defense Industrial Association (NDIA). The deployment of SE practices on a project or program was measured through the availability and characteristics of specific SE-related work products. Project Performance was measured through typically available project measures of cost performance, schedule performance, and scope performance. Additional project and program information such as project size, project domain, and other data was also collected to aid in characterizing the respondent's project. Analysis of the survey responses revealed moderately strong statistical relationships between Project Performance and several categorizations of specific of SE best practices. Notably stronger relationships are apparent by combining the effects of more than one the best practices categories. Of course, Systems Engineering Capability alone does not ensure outstanding Project Performance. The survey results show notable differences in the relationship between SE best practices and performance between more challenging as compared to less challenging projects. The statistical relationship between Project Performance and the combination of SE Capability and Project Challenge is quite strong for survey data of this type

    Review and Recommendations of Existing Methods and Tools for Building Energy Analysis: Subtask 2.4 for the Southern Energy Efficiency Center

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    ESL-TR-09-04-01The Southern Energy Efficiency Center (SEEC) was established to substantially increase the deployment of high-performance “beyond-code” buildings across the southern region of the U.S. It is funded by the U.S. Department of Energy (DOE) Building Technologies Program and administered by the National Energy Technology Laboratory. During its first 18-month phase, to expand the use of existing methods, procedures and tools for building energy efficiency in the marketplace; project efforts include identifying the existing tools from very simple calculators for estimating energy savings to detailed methods for measurement and verification of commercial building energy savings and defining their technical and practical characteristics. This work is defined under the SEEC Subtask 2.4 Expand the Use of Existing Methods and Tools. This report presents preliminary deliverables of this subtask developed and documented by the Energy Systems Laboratory (ESL) for use by the SEEC member state region. The primary goal of this subtask is to provide the state energy offices with the list of available tools and recommendations for use. By scrutinizing the information gathered, these recommendations have been developed to encourage the use of a number of existing tools that are not widely used, but provide valuable information and insight on the benefits of building energy efficiency in the SEEC member states. The resultant summary spreadsheet will also allow them to choose the appropriate tool, either simple calculators or detailed methods, according to the inquiry

    Framework for self-aware management of goals and constraints in computing systems

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    Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (p. 165-172).Modern computing systems require applications to balance competing goals, e.g.,high performance and low power or high performance and high precision. Achieving the right balance for a particular application and system places an unrealistic burden on application programmers who must understand the power, performance, and precision implications of a variety of application and system configurations (e.g.,changing algorithms or allocating cores). To address this problem, we propose the Self-aware Computing framework, or SEEC. SEEC automatically and dynamically configures systems and applications to meet goals accurately and efficiently. While other self-aware implementations have been proposed, SEEC is uniquely distinguished by its decoupled approach, which allows application and systems programmers to separately specify goals and configurations, each according to their expertise. SEEC's runtime decision engine observes and configures the system automatically, reducing programmer burden. This general and extensible decision engine employs both control theory and machine learning to reason about previously unseen applications and system configurations while automatically adapting to changes in both application and system behavior. This thesis describes the SEEC framework and evaluates it in several case studies. SEEC is evaluated by implementing its interfaces and runtime system on multiple, modern Linux x86 servers. Applications are then instrumented to emit goals and progress, while system services are instrumented to describe available adaptations. The SEEC runtime decision engine is then evaluated for its ability to meet goals accurately and efficiently. For example, SEEC is shown to meet performance goals with less than 3% average error while bringing average power consumption within 92% of optimal. SEEC is also shown to meet power goals with less than 2% average error while achieving over 96% of optimal performance on average. Additional studies show SEEC reacting to maintain performance in response to unexpected events including fluctuations in application workload and reduction in available resources. These studies demonstrate that SEEC can have a positive impact on real systems by understanding high level goals and adapting to meet those goals online.by Henry Hoffmann.Ph.D

    River Ecological Restoration and Groundwater Artificial Recharge

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    Three of the eleven papers focused on groundwater recharge and its impacts on the groundwater regime, in which recharge was caused by riverbed leakage from river ecological restoration (artificial water replenishment). The issues of the hydrogeological parameters involved (such as the influence radius) were also reconsidered. Six papers focused on the impact of river ecological replenishment and other human activities on river and watershed ecology, and on groundwater quality and use function. The issues of ecological security at the watershed scale and deterioration of groundwater quality were of particular concern. Two papers focused on water resources carrying capacity and water resources reallocation at the regional scale, in the context of the fact that ecological water demand has been a significant topic of concern. The use of unconventional water resources such as brackish water has been emphasized in the research in this issue

    C-type lectin-like domains in Fugu rubripes

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    BACKGROUND: Members of the C-type lectin domain (CTLD) superfamily are metazoan proteins functionally important in glycoprotein metabolism, mechanisms of multicellular integration and immunity. Three genome-level studies on human, C. elegans and D. melanogaster reported previously demonstrated almost complete divergence among invertebrate and mammalian families of CTLD-containing proteins (CTLDcps). RESULTS: We have performed an analysis of CTLD family composition in Fugu rubripes using the draft genome sequence. The results show that all but two groups of CTLDcps identified in mammals are also found in fish, and that most of the groups have the same members as in mammals. We failed to detect representatives for CTLD groups V (NK cell receptors) and VII (lithostathine), while the DC-SIGN subgroup of group II is overrepresented in Fugu. Several new CTLD-containing genes, highly conserved between Fugu and human, were discovered using the Fugu genome sequence as a reference, including a CSPG family member and an SCP-domain-containing soluble protein. A distinct group of soluble dual-CTLD proteins has been identified, which may be the first reported CTLDcp group shared by invertebrates and vertebrates. We show that CTLDcp-encoding genes are selectively duplicated in Fugu, in a manner that suggests an ancient large-scale duplication event. We have verified 32 gene structures and predicted 63 new ones, and make our annotations available through a distributed annotation system (DAS) server and their sequences as additional files with this paper. CONCLUSIONS: The vertebrate CTLDcp family was essentially formed early in vertebrate evolution and is completely different from the invertebrate families. Comparison of fish and mammalian genomes revealed three groups of CTLDcps and several new members of the known groups, which are highly conserved between fish and mammals, but were not identified in the study using only mammalian genomes. Despite limitations of the draft sequence, the Fugu rubripes genome is a powerful instrument for gene discovery and vertebrate evolutionary analysis. The composition of the CTLDcp superfamily in fish and mammals suggests that large-scale duplication events played an important role in the evolution of vertebrates

    Towards displacing domestic air conditioning in KSA, an assessment of hybrid cooling strategies integrated with 'Fabric First' passive design measures

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    Reducing energy use and CO2 emissions to curb global warming and climate change are the greatest challenges now facing mankind. The vast majority of energy generated from fossil fuels is burned to run vehicles, fuel power stations and cool or heat homes. Saudi Arabia, the world's largest producer and exporter of petroleum, currently consumes almost three times higher than the world average energy use and hence; ranked ninth among nations for CO2 emissions. Among all fossil energy consumers, residential buildings use almost half of the Saudi's prime energy sources and are responsible for almost 50% of the emitted CO2. In such a hot climate region, air conditioning (AC) of dwellings is by far the major consumer representing 69% of domestic energy use and drives peak loading. Future projections predict a continuous increase in energy use as the majority of existing buildings are poorly designed for the prevailing climate, leading to excessive use of mechanical AC. Therefore, it is crucial for Saudi Arabia to consider a horizon where hydrocarbons are not the dominant energy resource. The adoption of energy efficiency measures and low carbon cooling strategies may have the potential to displace a substantial percentage of oil currently used to run conventional AC plants. Therefore, the current study investigates the viability of 'fabric first' intelligent architectural design measures, in combination with hybrid ground cooling pipes integrated with black-body radiant night cooling systems, with a specific purpose to displace AC systems and decrease the carbon footprint while sustaining year-round thermal comfort. The interrogation of this hypothesis was addressed in three stages. The first stage was to generate a baseline analysis of the thermo-physical and energy performance of a typical residential block in Jeddah. The second stage involved developing an alternative low energy cooling approach that could handle high ambient temperatures. The task involved designing ground pipe ventilation integrated with high emissivity blackbody radiator to displace AC systems. The design of such 'hybrid' system required a parametric analysis combined with testing prototypes in field trials to establish actual ground temperatures at various depths and black body emissivity ranges under different sky conditions. This hybrid system became the subject of numerical modelling and simulation using DesignBuilder software in conjunction with EnergyPlus simulation engine. The third stage was to assess the simulation results and validate the cooling efficiency and cost-effectiveness of the hybrid system compared to the baseline. The preliminary results of prototype thermal simulation and field trials suggest that 'fabric first' passive designs and measures (PDMs), combined with night hydronic radiant cooling (HRCS) and supply ventilation via ground pipes (GPCS), can negate the necessity for a standard AC system by displacing over 80% of cooling demand and lower the carbon footprint of a typical housing block by over 75%. Such passive and hybrid system applications also have a remarkably short payback period with energy savings offsetting the capital costs associated with building thermo-physical enhancement.Reducing energy use and CO2 emissions to curb global warming and climate change are the greatest challenges now facing mankind. The vast majority of energy generated from fossil fuels is burned to run vehicles, fuel power stations and cool or heat homes. Saudi Arabia, the world's largest producer and exporter of petroleum, currently consumes almost three times higher than the world average energy use and hence; ranked ninth among nations for CO2 emissions. Among all fossil energy consumers, residential buildings use almost half of the Saudi's prime energy sources and are responsible for almost 50% of the emitted CO2. In such a hot climate region, air conditioning (AC) of dwellings is by far the major consumer representing 69% of domestic energy use and drives peak loading. Future projections predict a continuous increase in energy use as the majority of existing buildings are poorly designed for the prevailing climate, leading to excessive use of mechanical AC. Therefore, it is crucial for Saudi Arabia to consider a horizon where hydrocarbons are not the dominant energy resource. The adoption of energy efficiency measures and low carbon cooling strategies may have the potential to displace a substantial percentage of oil currently used to run conventional AC plants. Therefore, the current study investigates the viability of 'fabric first' intelligent architectural design measures, in combination with hybrid ground cooling pipes integrated with black-body radiant night cooling systems, with a specific purpose to displace AC systems and decrease the carbon footprint while sustaining year-round thermal comfort. The interrogation of this hypothesis was addressed in three stages. The first stage was to generate a baseline analysis of the thermo-physical and energy performance of a typical residential block in Jeddah. The second stage involved developing an alternative low energy cooling approach that could handle high ambient temperatures. The task involved designing ground pipe ventilation integrated with high emissivity blackbody radiator to displace AC systems. The design of such 'hybrid' system required a parametric analysis combined with testing prototypes in field trials to establish actual ground temperatures at various depths and black body emissivity ranges under different sky conditions. This hybrid system became the subject of numerical modelling and simulation using DesignBuilder software in conjunction with EnergyPlus simulation engine. The third stage was to assess the simulation results and validate the cooling efficiency and cost-effectiveness of the hybrid system compared to the baseline. The preliminary results of prototype thermal simulation and field trials suggest that 'fabric first' passive designs and measures (PDMs), combined with night hydronic radiant cooling (HRCS) and supply ventilation via ground pipes (GPCS), can negate the necessity for a standard AC system by displacing over 80% of cooling demand and lower the carbon footprint of a typical housing block by over 75%. Such passive and hybrid system applications also have a remarkably short payback period with energy savings offsetting the capital costs associated with building thermo-physical enhancement

    Scalable and Distributed Resource Management for Many-Core Systems

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    Many-core systems provide researchers with important new challenges, including the handling of very dynamic and hardly predictable computational loads. The large number of applications and cores causes scalability issues for centrally acting heuristics, which always must retain a global view of the entire system. Resource management itself can become a bottleneck which limits the achievable performance of the system. The focus of this work is to achieve scalability of resource management

    Factors influencing in selection of online banking products: a conceptual paper on Bangladeshi customer

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    Abstract The study has been led to research the components that impact the clients of electronic banking services to utilize internet banking in Bangladesh. In this study there has been utilizing diverse compelling components that has an extraordinary effect to rouse or impact the internet banking client in determination of their web based banking framework in Bangladesh will be examine and with different analytical procedures. It has been seen from the result of the literature that, the ease of usefulness is the most critical component that impacts the client in choice of internet banking. Different questions will be asked to determine the most influencing term under use of usefulness. On perception, a proper policy may go a long way to increase the ease use online banking system with the improvement of other related facilities which will help the online banking system to attract the new clients. Keywords: Ease of usefulness, online bank, Security and Privacy, Customer satisfactio

    Heat Transfer in Energy Conversion Systems

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    In recent years, the scientific community’s interest towards efficient energy conversion systems has significantly increased. One of the reasons is certainly related to the change in the temperature of the planet, which appears to have increased by 0.76 °C with respect to pre-industrial levels, according to the Intergovernmental Panel on Climate Change (IPCC), and this trend has not yet been stopped. The European Union considers it vital to prevent global warming from exceeding 2 °C with respect to pre-industrial levels, since this phenomenon has been proven to result in irreversible and potentially catastrophic changes. These climate changes are mainly caused by the emissions of greenhouse gasses related to human activities, and can be drastically reduced by employing energy systems, for both heating and cooling of buildings and for power production, characterized by high efficiency levels and/or based on renewable energy sources. This Special Issue, published in the journal Energies, includes 12 contributions from across the world, including a wide range of applications, such as HT-PEMFC, district heating systems, a thermoelectric generator for industrial waste, artificial ground freezing, nanofluids, and others
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