• Earthquakes and Structures
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• v.10 no.2
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• pp.429-450
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• 2016

An attempt has been made to incorporate the concept of collapse safety margin into the procedures proposed in the performance-based earthquake engineering (PBEE) framework for direct earthquake loss estimation, in which the collapse probability curve obtained from incremental dynamic analysis (IDA) is mathematically characterized with the S-type fitting model. The regressive collapse probability curve is then used to identify non-collapse cases and collapse cases. With the assumed lognormal probability distribution for non-collapse damage indexes, the expected direct earthquake loss ratio is calculated from the weighted average over several damage states for non-collapse cases. Collapse safety margin is shown to be strongly related with sustained damage endurance of structures. Such endurance exhibits a strong link with expected direct earthquake loss. The results from the case study on three concrete frames indicate that increase in cross section cannot always achieve a more desirable output of collapse safety margin and less direct earthquake loss. It is a more effective way to acquire wider collapse safety margin and less direct earthquake loss through proper enhancement of reinforcement in structural components. Interestingly, total expected direct earthquake loss ratio seems to be insensitive a change in cross section. It has demonstrated a consistent correlation with collapse safety margin. The results also indicates that, if direct economic loss is seriously concerned, it is of much significance to reduce the probability of occurrence of moderate and even severe damage, as well as the probability of structural collapse.

• Journal of Environmental Policy
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• v.2 no.2
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• pp.17-40
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• 2003

The objective of this paper is to formulate strategies and action programs for developing sustainable agriculture in Korea. There is increasing evidence that agriculture has been preoccupied with increasing productivity much to the detriment of environmental degradation. The issue of increasing agricultural productivity so as not to undermine the environment is a difficult task. In reality, there are many definitions of sustainable agriculture and sustainable agricultural development. In this paper, sustainable agriculture is defined by its ability to ensure future supplies of agricultural products at acceptable economic and environmental costs to the society. Sustainable agriculture development refers to the optimal level of interaction among the three dimensions - the environmental, the economic and the social - through dynamic and adaptive processes of trade-off. In order to formulate the strategies for developing sustainable agriculture, three stage approaches such as strategic analysis, strategic choice, and strategic implementation are employed. The basic framework for strategies of sustainable agriculture development consists of five steps such as vision, targets, principles, action plan and policy instruments. The major action plans for activating formulated strategies are suggested as integrating agricultural and environmental policy measures, establishing the system of optimal agri-environmental resources management practices, establishing safe and high quality product system and its effective marketing system, increasing the R&D investment for developing sustainable agro-technology, developing indicators for measuring sustainable agricultural development, and taking a share in related roles for all parties including farmers, consumers, policy makers, researchers and NGOs.

• Structural Engineering and Mechanics
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• v.46 no.1
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• pp.19-37
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• 2013

The optimum design of base isolation system considering model parameter uncertainty is usually performed by using the unconditional response of structure obtained by the total probability theory, as the performance index. Though, the probabilistic approach is powerful, it cannot be applied when the maximum possible ranges of variations are known and can be only modelled as uncertain but bounded type. In such cases, the interval analysis method is a viable alternative. The present study focuses on the bounded optimization of base isolation system to mitigate the seismic vibration effect of structures characterized by bounded type system parameters. With this intention in view, the conditional stochastic response quantities are obtained in random vibration framework using the state space formulation. Subsequently, with the aid of matrix perturbation theory using first order Taylor series expansion of dynamic response function and its interval extension, the vibration control problem is transformed to appropriate deterministic optimization problems correspond to a lower bound and upper bound optimum solutions. A lead rubber bearing isolating a multi-storeyed building frame is considered for numerical study to elucidate the proposed bounded optimization procedure and the optimum performance of the isolation system.

• Structural Engineering and Mechanics
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• v.47 no.2
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• pp.227-245
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• 2013

The term "constructability" in regard to cast-in-place concrete construction refers mainly to the ease of reinforcing steel placement. Bar congestion complicates steel placement, hinders concrete placement and as a result leads to improper consolidation of concrete around bars affecting the integrity of the structure. In this paper, a multi-objective approach, based on the non-dominated sorting genetic algorithm (NSGA-II) is developed for optimal design of reinforced concrete cantilever retaining walls, considering minimization of the economic cost and reinforcing bar congestion as the objective functions. The structural model to be optimized involves 35 design variables, which define the geometry, the type of concrete grades, and the reinforcement used. The seismic response of the retaining walls is investigated using the well-known Mononobe-Okabe analysis method to define the dynamic lateral earth pressure. The results obtained from numerical application of the proposed framework demonstrate its capabilities in solving the present multi-objective optimization problem.

• International Journal of Costume and Fashion
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• v.13 no.2
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• pp.65-77
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• 2013

The purposes of this study were to document the fashions adopted by young women in the United States in the 1980s and to explore if and how the dynamic shifts toward postmodernist values influenced those fashion trends. Fifteen U.S. women who were college students in the 1980s were interviewed for the study. In analysis of the data, we focused on social changes during the 1980s and the cultural impact of postmodernism vs. modernism as influential factors. Both postmodern and feminist ideas challenged the mainstream cultural framework of capitalism. U.S. women's styles and behaviors concerning dress reflected characteristics of postmodern consumption patterns, which include nostalgia, ethnic dress, androgyny, eclectic and novel clothing combinations, surprising or humorous appearance, and nonconformity. Despite the critique of conformity and conservatism in dress that had emerged in the 1960s and remained in at least minority or subversive trends, the importance of brand names and designer labels increased in mainstream fashion. This study helps us better understand the dynamics of fashion as it reflects societal and value changes in a transitional time in history.

• Asia pacific journal of information systems
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• v.12 no.3
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• pp.135-167
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• 2002

This research focuses on the IS development methodology as an object of innovation in an IS organization. It has two main research objectives. It was intended to understand the critical affecting factors which have an effect on the processing of each level in the dynamic and evolving innovation process. There are two levels of innovation process: initiation and implementation. It was also intended to understand the performance of IS organizational innovation. We found three main results by the LISREL analysis. First, main factors affecting initiation level of innovation are innovative tendency of IS members, communication level of IS organization, existence of champion manager, IS performance gap, executive supporting to IS, and relative advantage of IS development methodology. At the implementation level, it was understood that the existence of champion manager, executive support, and relative advantage of IS development methodology were the main factors promoting to use the innovation, and the complexity of innovation was a negative factor adopting the usage of innovation. Second, the quality of the previous level in the gradual innovation activities gives very notable affection to the continuous next level. Finally, it was found that the qualitative performance like the documentation, collaborative team approach, IS developer's awareness and ability corresponding to their task and so on was improved due to the IS organizational innovation. This research provides the standard framework for the IS organizational innovation in a structural way. In the practical aspect, it may be used as the principle for introducing and using the IS development methodology.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.2977-2997
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• 2018

In big data era, fresh data grows rapidly every day. More than 30,000 gigabytes of data are created every second and the rate is accelerating. Many organizations rely heavily on real time streaming, while big data stream computing helps them spot opportunities and risks from real time big data. Storm, one of the most common online stream computing platforms, has been used for big data stream computing, with response time ranging from milliseconds to sub-seconds. The performance of Storm plays a crucial role in different application scenarios, however, few studies were conducted to evaluate the performance of Storm. In this paper, we investigate the performance of Storm under different application scenarios. Our experimental results show that throughput and latency of Storm are greatly affected by the number of instances of each vertex in task topology, and the number of available resources in data center. The fault-tolerant mechanism of Storm works well in most big data stream computing environments. As a result, it is suggested that a dynamic topology, an elastic scheduling framework, and a memory based fault-tolerant mechanism are necessary for providing high throughput and low latency services on Storm platform.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.635-644
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• 2004

A method of identifying structural parameters such as stiffness and damping coefficients at interfacial points of vibro-acoustic systems is suggested using an optimization technique. To identify the parameters using a numerical optimization algorithm, cost functions are defined. The cost function should be zero at the correct parameter values. To minimize the cost functions using an optimization technique, a design sensitivity analysis procedure is developed in the framework of the multi-domain FRF-based substructuring method. As a numerical example, a ladder-like structure problem is introduced. With known parameter values and different initial guesses of the parameters, convergence characteristics to the exact value are compared f3r the three cost functions. Investigating the contours of the cost functions, we find the first cost function has the largest convergent region to the correct value. As another practical problem, stiffnesses of engine mounts and bushings in a passenger car are identified. The numerical examples show that the proposed method is efficient and accurate far realistic problems.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.6
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• pp.536-545
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• 2004

A method of identifying structural parameters such as stiffness and damping coefficients at interfacial points of vibro-acoustic systems is suggested using an optimization technique. To identify the parameters using a numerical optimization algorithm, cost functions are defined. The cost function should be zero at the correct parameter values. To minimize the cost functions using an optimization technique, a design sensitivity analysis procedure is developed in the framework of the multi-domain FRF-based substructuring method. As a numerical example, a ladder-like structure problem is introduced. With known parameter values and different initial guesses of the parameters, convergence characteristics to the exact value are compared for the three cost functions. Investigating the contours of the cost functions, we find the first cost function has the largest convergent region to the correct value. As another practical problem, the stiffnesses of engine mounts and bushings in a passenger car are identified. The numerical examples show that the proposed method is efficient and accurate for realistic problems.

• Archives of design research
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• v.14 no.2
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• pp.107-116
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• 2001

Nowadays, The market environment is not static, but dynamic, it therefore requires global competition for the competitive advantage of product design in global market across boundaries. So if companies do not thoroughly understand core values, needs of consumers, and do not properly meet them, they cannot get the competitive advantage in global market for consumers. Therefore, the goal of this research is to develop a new design process for global markets through developing the on-line research analysis program and data-base. For this study, the researchers established a research framework associated with values, benefits and design attributes and developed a Global Design Process program through empirical researches. This research program is a upgraded system adapted to the digital period drastically.