Suchergebnisse

Probabilistic analysis of crack width of a reinforced concrete element is based on the formulas accepted in Eurocode 2 and European Model Code 90. Obtained values of reliability index b seem to be satisfactory for the reinforced concrete slab that fulfils requirements for the crack width specified in Eurocode 2. However, the reliability of the slab seems to be insufficient when the European Model Code 90 is considered; reliability index is less than recommended value 1.5 for serviceability limit states indicated in Eurocode 1. Analysis of sensitivity factors of basic variables enables to find out variables significantly affecting the total crack width.

Variation in the level of suburban government activity has been explained in several models, each approaching suburban government & budget making from ecological, stratification, & historical public choice perspectives, & each hypothesizing about which suburbs spend more & which less. The serviceability of these models is examined using regression analysis of municipal expenditures of 880 US suburbs selected from the 1972 Census of Governments. The analysis used community variables such as density, business activity, government structure, functional responsibility (ie, police, fire, parks, sanitation), median income, central city age, & % black. Variance in municipal expenditures (per capita) were most significantly explained through economic & responsibility functions. 2 Tables. Modified HA.

We suggested general polices that can be implemented to improve the sustainability and serviceability of the water sector in Jordan. It is suggested that water legislations in Jordan need to be updated to expand the involvement of the private sector to retain sustainable maintenance programmes that effectively mend water distribution systems. Moreover, water resources should be reallocated among competing sectors considering priority to users with purposes that are deemed to have the higher returns in economic and social terms. It is suggested that activating public awareness programmes will raise community understanding and support for water allocation plans among competing water use sectors and improve public participation in developing and accepting new policies related to water management.

Наведено результати досліджень суцільнометалевої водоохолоджувальної камери згорання для апаратів зануреного згорання з організацією багаторазової інверсії і модуляції коливань контактуючих фаз. Доведено високу енерготехнологічну ефективність розроблених пристроїв при використанні в системах децентралізованого опалення будівель і споруд, яка обумовлена високим ступенем ефективності теплообміну контактуючих фаз в апараті зануреного горіння. ; The high-effective contact-module system was developed. It was equipped with the immersion combustion apparatuses with multiple phase inversion and oscillation modulating of contacted phases. The system can be used for heat supply of industrial and agricultural buildings, apartment houses without using boilers with heat utilization of combustion products. Contact-module system has stood the government heat-ecological test, which confirmed its high efficiency, ecological compatibility, serviceability. Construction standard specifications for serial production in the different branches of economy were obtained.

"Constitutional change" brings to mind such central themes as the relationship of the federal constitutional court to the legislators, the methodology of constitutional interpretation, the admissibility of common law & unwritten constitutional law, & the limits of constitutional modification. Yet the function of constitutional change in text books & commentary literature is remarkably weak & begs the question of whether reliable instruction exists that goes beyond the association of existing special discourse, & for what specific purposes it might be used. The term "constitutional change" is clarified to distinguish the formal textual changes from the normative changes, & the concrete value & serviceability of sociological-empirical, methodological, dogmatic, & heuristic perspectives are examined. It is clear that an independent & reliable German science on constitutional change does not exist, & that such terminology should be sparingly employed. L. Kehl

Low serviceability of rural road networks in Colombia hinders economic development, and especially rural development. Municipalities have budget constraints, so it is important to develop low cost techniques for preventive and corrective maintenance of rural roads. Stabilization of rural roads using industrial by-products is an alternative to improve road conditions and to prevent negative impacts from sediment production. This paper presents a case study in which three non-commercial materials produced from industrial waste are used for stabilizing a road section in Urrao, Antioquia. Stabilization costs are compared for the three alternatives by adapting the life cycle cost analysis to the information available. In addition, assessed costs consider geographic and technical factors, as well as availability of residues. It is found that stabilization costs are highly sensitive to waste availability and location, to processed volumes and to transportation costs.

Military obsolescence affects the capability of all militaries as it relates to serviceability and performance when countering potential opponents, and more specifically in the case of developing countries lacking strong indigenous defence industries. The gradual nature of this military concern has not been studied systematically, in contrast to military modernisation. This paper presents a synthetic framework composed of several indicators to examine military obsolescence. Vietnam has been selected for the application of the framework for its large number of Cold War legacies and the strategic pressure from China. Hanoi's ageing assets would undermine its position vis-à-vis Beijing, and its defence investment policies face the dilemma of choosing to spend more on naval and aerial power, or ameliorating its army which is technologically lacking compared to its Chinese counterpart. (Pac Rev/GIGA)

AbstractWe study competitive due‐date and capacity management between the marketing and engineering divisions within an engineer‐to‐order (ETO) firm. Marketing interacts directly with the customers and quotes due‐dates for their orders. Engineering is primarily concerned with the efficient utilization of resources and is willing to increase capacity if the cost is compensated. The two divisions share the responsibility for timely delivery of the jobs. We model the interaction between marketing and engineering as a Nash game and investigate the effect of internal competition on the equilibrium decisions. We observe that the internal competition not only degrades the firm's overall profitability but also the serviceability. Finally, we extend our analysis to multiple‐job settings that consider both flexible and inflexible capacity. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008

Doctrinally, the U.S. Army determines the readiness of company-sized and battalionsized units by assessing them in four areas: personnel, equipment on hand, equipment serviceability, and training to meet mission-essential tasks. Surprisingly, these assessments do not include factors identified in surveys, personal interviews, and observational accounts of soldiers regarding what prepares them for combat and contributes to their combat effectiveness. Among the more prominent of these factors are the quality of small (primary) group relationships and the competencies of unit leaders. The present study considers these factors in addition to doctrinal readiness assessments. Soldier perceptions combined with doctrinal assessments (1) more readily differentiated the readiness of units; (2) were associated with independently derived soldier perceptions of fellow soldiers, leaders, and equipment being prepared for combat operations; and (3) implied interventions to improve specific unit activities.

Steel-concrete composite girders have attractive potentials when applied in bridge construction. The serviceability performance of continuous composite girders is becoming more and more a deterministic parameter in the design of this type of structures. An effective method for improving this performance is to apply prestressing to control or completely eliminate concrete deck cracking caused by static and time dependent actions. Little literature has been found addressing the experimental analysis of continuous girders prestressed by means of external deviated tendons. The current research aims to investigate the behavior of a double-span steel composite beam externally prestressed by means of continuous tendons in terms of cracking characteristics, load deflection response, and load carrying capacity. The efficiency of prestressing is evaluated by comparing the results to those of a non-prestressed beam with similar cross sections and spans.

"In view of the development of world concrete and construction, we see an evolution of the focus in the direction of: Safety Durability Serviceability/Functionality Sustainability It is important in this context to learn at least two things: - All the focuses in the evolution process are closely linked to each other and function upon need instead of occurring and existing independently or replacing one by another. - The latest developed focus - Sustainability is not only evolved from the previous focuses but works as a function of them as well. We therefore believe that sustainability is not only an environmental performance, it is indeed a holistic thinking/approach that can be considered as the function of safety, durability, functionality and economical feasibility, environmental compatibility and social responsibility. The level/magnitude of each focus to sustainability varies depending on the specific requirement of the target and local boundary conditions"--

The article deals with a method for analysing slender masonry columns. The proposed method uses material and geometric non-linearity. Various stress-strain diagrams can be used: linear, linear-plastic, parabolic-plastic, two various parabolic and rigid-plastic. In all cases, the tensile strength is neglected. The method can be used for analysing the column in accordance with Eurocodes in two ways: SLS (serviceability limit state) and ULS (ultimate limit state). The internal forces are calculated on a general beam model, with imperfections in both directions, which result in two bending moments in two perpendicular planes – biaxial bending. This case is not covered by the current code – Eurocode, even though all columns are more or less loaded in both directions. In this numerical study, using Matlab software, an algorithm was developed for modelling a real 3D case. The results of this study are also compared to the results of laboratory tests of masonry columns.

The Argentine Air Force (AAF) is facing increasing challenges in maintaining and sustaining trainer aircraft. The current trainer aircraft used by the AAF face obsolescence issues and decreased serviceability. Argentina used to have the largest aircraft industry among the Latin America countries, but a number of factors such as not maintaining objectives and policies over time undermined its consolidation and were instrumental in Argentina losing its leadership position. To meet AAF requirements and revive Argentina's domestic aircraft industry, an indigenous basic trainer aircraft project is proposed. The purpose of this thesis is to evaluate the project's viability using a multi-criteria analysis methodology. The evaluation reveals which actions contribute toward the AAF goal of increasing training aircraft availability. An economic analysis also was performed to determine costs vs. benefits and cost efficiency. The proposed option minimizes aircraft inventory diversity while maximizing consistency, sustainability, and versatility.

Doctrinally, the U.S. Army determines the readiness of company-sized and battalion-sized units by assessing them in four areas: personnel, equipment on hand, equipment serviceability, and training to meet mission-essential tasks. Surprisingly, these assessments do not include factors identified in surveys, personal interviews, and observational accounts of soldiers regarding what prepares them for combat and contributes to their combat effectiveness. Among the more prominent of these factors are the quality of small (primary) group relationships and the competencies of unit leaders. The present study considers these factors in addition to doctrinal readiness assessments. Soldier perceptions combined with doctrinal assessments (1) more readily differentiated the readiness of units; (2) were associated with independently derived soldier perceptions of fellow soldiers, leaders, and equipment being prepared for combat operations; and (3) implied interventions to improve specific unit activities. Adapted from the source document.

The focus of this research is using system dynamics modeling to evaluate the impact of missed scheduled maintenance due to budgetary constraints. Missed maintenance cannot be made up and the benefit to the facility's serviceability is lost. The cumulative effect on an entire facility's life span is that it is unable to reach its designed life expectancy. Replacement construction costs are hundreds, thousands, or millions times more than the annual maintenance repair costs. Therefore, Air Force civil engineers must be capable of evaluating maintenance strategies in a dynamic environment to determine the budget strategy's prolonged effect on infrastructure serviceable life. The results of the evaluation demonstrate how five major categories of infrastructure maintenance budgets change infrastructure's serviceable life. The modeling process provides considerable insight into these budget methods that must be considered to determine what is best for the infrastructures serviceable life.