• Journal of Korean Society of Industrial and Systems Engineering
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• v.47 no.2
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• pp.168-175
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• 2024

Due to the complexity of urban area, the city vehicle routing problem has been a difficult problem. The problem has involved factors such as parking availability, road conditions, and traffic congestion, all of which increase transportation costs and delivery times. To resolve this problem, one effective solution can be the use of parcel lockers located near customer sites, where products are stored for customers to pick up. When a vehicle delivers products to a designated parcel locker, customers in the vicinity must pick up their products from that locker. Recently, identifying optimal locations for these parcel lockers has become an important research issue. This paper addresses the parcel locker location problem within the context of urban traffic congestion. By considering dynamic environmental factors, we propose a Markov decision process model to tackle the city vehicle routing problem. To ensure more real situations, we have used optimal paths for distances between two nodes. Numerical results demonstrate the viability of our model and solution strategy.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.1
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• pp.67-82
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• 2009

This paper examines the regional economic development policies of the Welsh Development Agency for attracting companies from the perspective of industrial location theory. The Welsh Development Agency has succeeded in attracting domestic or international capital, as a core actor for the regional economic development, and responded to the changing business environment and to the specific and various needs of the investors. The analysis of the Welsh case provides an important theoretical and practical implications. First, the Welsh case shows the importance of the role of the public sectors for the regional economic development. As the behavioral approach and the industrial location theory argue, the attraction of domestic or international capital led to the regional economic development. Second, the effective activities for attracting capital played an important role in the development. The quality and quantity of the information, in the industrial location theory, and the capacity of the business groups, in the behavioral approach, are significant factors of the development. Third, incentives by the Agency are also important. This finding not only supports the classical location model based on the cost and profits, but also the behavioral approach. Finally, the Welsh case could not succeeded in gaining regional economic competitiveness, even though attracting companies, by disregarding the industrial specialization strategy at the local level. This implies that we need to build industrial clusters. In sum, the behavioral approach has significant implications to the understanding of the public policies for attracting companies.

• Journal of Gastric Cancer
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• v.18 no.3
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• pp.209-217
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• 2018

Although the incidence of gastroesophageal junction (GEJ) adenocarcinoma has been increasing worldwide, no standardized surgical strategy for its treatment has been established. This study aimed to provide an update on the surgical treatment of GEJ adenocarcinoma by reviewing previous reports and propose recommended surgical approaches. The Siewert classification is widely used for determining which surgical procedure is used, because previous studies have shown that the pattern of lymph node (LN) metastasis depends on tumor location. In terms of surgical approaches for GEJ adenocarcinoma, a consensus was reached based on two randomized controlled trials. Siewert types I and III are treated as esophageal cancer and gastric cancer, respectively. Although no consensus has been reached regarding the treatment of Siewert type II, several retrospective studies suggested that the optimal treatment strategy includes paraaortic LN dissection. Against this background, a Japanese nationwide prospective trial is being conducted to determine the proportion of LN metastasis in GEJ cancers and to identify the optimal extent of LN dissection in each type.

• Fashion & Textile Research Journal
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• v.9 no.1
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• pp.72-80
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• 2007

The purpose of this study is to identify the latest trend and type of retail space, and the features according to type of retail space of global prestige brand. To do this, literature analysis was executed by related books, articles, and theses. As a result, the latest trend of fashion retail space which has appeared after 2000 is as follows: 1) The differentiation of fashion brand through collaboration between fashion designers and architects, 2) retail space extension strategy, 3) retail space as a cultural space, 4) bold investment for retail space. The type of fashion retail space which has appeared after 2000 is as follows: 1) Spectacular flagship retail space of monumental scale, 2) global type retail space which exhibits common features through the whole world, 3) localization retail space which shows different features according to store location 4) innovative retail space out of traditional store form. The result of this study will be utilized when a domestic fashion brand establishes global marketing strategy of retail space.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.69
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• pp.473-493
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• 2016

If a certain country or an arbitration institution hopes to keep ahead of the fierce competition in the international arbitration market, it needs to develop hardware factors, such as i) Facility and Infra, ii) Geographical Location, iii) Professional Staff, iv) Global Network, v) Capital, and vi) Arbitrators & Practitioners etc., along with software factors including i) Arbitration Rules of Law, ii) Court's Support, iii) International Convention, iv) Political Risk, and v) Education Environment, which are the most critical requirements in the development strategy for international arbitration. Having perceived the above situation, the Korean government has been working on amending the Korean Arbitration Act to reflect global advanced practice of international arbitration, and seeking to enact laws that will promote our arbitration industry and create a more arbitration-friendly environment. The KCAB is also currently revising both the domestic and international arbitration rules in accordance with these national efforts. Under these circumstances, this paper examines how major leading international arbitration institutions manage their secretariats and suggests how the KCAB can compose and manage its Secretariat to gain a competitive advantage over rival institutions.

• Structural Engineering and Mechanics
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• v.64 no.1
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• pp.45-58
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• 2017

This paper presents the application of topology optimization as a design tool for a steel railway bridge. The choice of a steel railway bridge is dictated by the particular situation that it is suitable for topology optimization design. On the one hand, the current manufacturing techniques for steel structures (additive manufacturing techniques not included) are highly appropriate for material optimization and weight reduction to improve the overall structural efficiency, improve production efficiency, and reduce costs. On the other hand, the design of a railway bridge, especially at higher speeds, is dominated by minimizing the deformations, this being the basic principle of compliance optimization. However, a classical strategy of topology optimization considers typically only one or a very limited number of load cases, while the design of a steel railway bridge is characterized by relatively concentrated convoy loads, which may be present or absent at any location of the structure. The paper demonstrates the applicability of considering multiple load configurations during topology optimization and proves that a different and better optimal layout is obtained than the one from the classical strategy.

• Structural Engineering and Mechanics
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• v.58 no.1
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• pp.163-179
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• 2016

The Cuckoo search (CS) algorithm is a simple and efficient global optimization algorithm and it has been applied to figure out large range of real-world optimization problem. In this paper, a new formula is introduced to the discovering probability process to improve the convergence rate and the Tournament Selection Strategy is adopted to enhance global search ability of the certain algorithm. Then an approach for structural damage identification based on modified Cuckoo search (MCS) is presented. Meanwhile, we take frequency residual error and the modal assurance criterion (MAC) as indexes of damage detection in view of the crack damage, and the MCS algorithm is utilized to identifying the structural damage. A simply supported beam and a 31-bar truss are studied as numerical example to illustrate the correctness and efficiency of the propose method. Besides, a laboratory work is also conducted to further verification. Studies show that, the proposed method can judge the damage location and degree of structures more accurately than its counterpart even under measurement noise, which demonstrates the MCS algorithm has a higher damage diagnosis precision.

• Korean Journal of Computational Design and Engineering
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• v.4 no.4
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• pp.318-326
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• 1999

Recently, electronic systems including computers have been rapidly shrinking in size while at the same time the complexity and the capability of these systems continue to grow/sup [1]/. Thus, system volumes have decreased as system power has increased, resulting in dramatic increases in system heat density. The high temperature of the computer system is considered as the major reason for low performance and shortening life of the product. It is necessary to solve this problem due to the heat density increased and to develop the design skill of the computer cabinet according to miniaturization. M4500 desk-top computer was selected for analyzing the thermal management inside cabinet. The cabinet volume, the configuration of the heating devices, the size and location of air ventilation, and the fan selection have been investigated as the important parameters to find out an optimal cabinet design. The objectives of this project were to analyze which design parameters would affect cooling performance by thermal strategy, to design an optimal model, and to measure the temperatures of the main parts to confirm the effect of the thermal design. The temperatures of each part of the optimal model were compared with those of the existing model. As a result. the volume of this miniaturized model was about 16% smaller than that of M4500 without any change in operating performance.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.1
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• pp.215-236
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• 2017

Obtaining accurate location information is important in practical applications of wireless sensor networks (WSNs). The distance vector hop (DV-Hop) is a frequently-used range-free localization algorithm in WSNs, but it has low localization accuracy. Moreover, despite various improvements to DV-Hop-based localization algorithms, maintaining a balance between high localization accuracy and good stability and convergence is still a challenge. To overcome these shortcomings, we proposed an improved DV-Hop localization algorithm based on the bat algorithm (IBDV-Hop) for WSNs. The IBDV-Hop algorithm incorporates optimization methods that enhance the accuracy of the average hop distance and fitness function. We also introduce a nonlinear dynamic inertial weight strategy to extend the global search scope and increase the local search accuracy. Moreover, we develop an updated solutions strategy that avoids premature convergence by the IBDV-Hop algorithm. Both theoretical analysis and simulation results show that the IBDV-Hop algorithm achieves higher localization accuracy than the original DV-Hop algorithm and other improved algorithms. The IBDV-Hop algorithm also exhibits good stability, search capability and convergence, and it requires little additional time complexity and energy consumption.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.8
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• pp.757-766
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• 2004

This paper focuses on the formulation and validation of an automatic strategy to select the optimal location and direction of strain gauges for the measurement of the modal response. These locations and directions are important to render the strain measurements as robust as possible when a random mispositioning of the gauges and gauge failures are expected. The approach relies on the evaluation of the signal-to-noise ratios of the gauge measurements from strain data of finite element. The multi-step optimization strategy including genetic algorithm is used to find the strain gauge locations-directions that maximize the smallest modal strain signal-to-noise ratio in the absence of gauge failure or its expected value when gauge failure is possible. A flat Plate is used to prove the applicability of the proposed methodology and to demonstrate the effects of the essential parameters of the problem such as the mispositioning level, the probability of gauge failure, and the number of gauges.