• Title/Summary/Keyword: Branch-and-price

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Analytic Comparisons of Shipbuilding Competitiveness between China and Korea

  • Lee, Koung-Rae
    • Journal of Korea Trade
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    • v.23 no.4
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    • pp.1-16
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    • 2019
  • Purpose - This research empirically proves that global shipbuilding industry leadership has moved to China from Korea. Design/Methodology - Competitiveness is measured by AHP for the weights of comprehensive competitiveness, which is the output mixture of three attributive factors: shipbuilding technology, shipbuilding contract price, and export credit. Findings - China is far ahead of Korea for standard vessels such as bulkers and containerships with competitiveness weights of 0.762 and 0.612, respectively, against 0.238 and 0.388 of Korea. Korea is maintaining its competitiveness only in LNG carriers (174k CBM) with a competitiveness weight 0.621. China and Korea have similar competitiveness for chemical carriers, complex vessels with a small hull size. The sources of Chinese competitiveness are shipbuilding contract price and export credit. With the majority share of standard vessel types in the world fleet, China will hold a bigger market share than Korea in the global shipbuilding industry in the forthcoming years. Implications - The swing factors of market power are shipbuilding technology and contract price. If China fails to further develop shipbuilding technology for shipowners worried about the reliability of the Chinese-built vessels, shipowners may swing back to Korea. The rising Chinese labor cost will expedite this swing in the forthcoming competition. Originality/value - To the best of the author's knowledge, this is the first paper that quantitatively examines the competitiveness of shipbuilding between China and Korea by comparing attributive factors for competitiveness.

Factors Affecting Foreign Direct Investment: Evidence on Tay Ninh Province

  • TRAN, Thinh Quoc;DANG, Tuan Anh;TRAN, Ngoc Anh Thu
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.9
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    • pp.263-269
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    • 2020
  • The purpose of this paper is to examine the impact of consumer price index, infrastructure, human resources, trade openness, and private credit on the attraction of foreign direct investment (FDI) in Tay Ninh province as well as to emphasize the important role of FDI in economic growth of developing areas. The research data was collected from Tay Ninh Statistical Office with 80 samples of a 20-year period from 2000 to 2019. Also, OLS regression method using Eviews software was employed to analyze the data obtained. The findings revealed that human resources, infrastructure and private credit have a positive and significant impact on FDI attraction in Tay Ninh province, while consumer price index was proven to affect FDI attraction negatively. Accordingly, competent authorities of Tay Ninh province should focus on stabilizing prices as well as implementing policies for developing local human resources and attracting high-quality personnel from foreign countries. Tay Ninh province also needs to pay more attention to information technology investment for synchronous development of infrastructure. Moreover, the State Bank of Tay Ninh branch needs to consider more credit sources to provide support packages for businesses, creating a strong basis for establishments to attract FDI for the province's economic development.

Multi-ring Design Algorithm for Survivable WDM Networks (WDM 망에서의 다중 링 설계 알고리즘 연구)

  • Chung, Ji-Bok
    • Korean Management Science Review
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    • v.26 no.3
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    • pp.1-9
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    • 2009
  • In this paper, we present mathematical models for the ring covering problems arising in the design of multi-ring WDM networks. Also, we present efficient algorithms to solve the suggested models. By the computational experiment, our model can solve the medium-sized networks efficiently and shows better performance than the existing heuristic method. Although we propose an efficient method for the column generation procedure, branching rule that does not destroy the column generation structure is unsolved. Further research is required to develop an effective branching rule.

Optimization Algorithm of Gantry Route Problem for Odd-type Surface Mount Device (이형 부품 표면실장기에 대한 겐트리 경로 문제의 최적 알고리즘)

  • Jeong, Jaewook;Tae, Hyunchul
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.43 no.4
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    • pp.67-75
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    • 2020
  • This paper proposes a methodology for gantry route optimization in order to maximize the productivity of a odd-type surface mount device (SMD). A odd-type SMD is a machine that uses a gantry to mount electronic components on the placement point of a printed circuit board (PCB). The gantry needs a nozzle to move its electronic components. There is a suitability between the nozzle and the electronic component, and the mounting speed varies depending on the suitability. When it is difficult for the nozzle to adsorb electronic components, nozzle exchange is performed, and nozzle exchange takes a certain amount of time. The gantry route optimization problem is divided into the mounting order on PCB and the allocation of nozzles and electronic components to the gantry. Nozzle and electronic component allocation minimized the time incurred by nozzle exchange and nozzle-to-electronic component compatibility by using an mixed integer programming method. Sequence of mounting points on PCB minimizes travel time by using the branch-and-price method. Experimental data was made by randomly picking the location of the mounting point on a PCB of 800mm in width and 800mm in length. The number of mounting points is divided into 25, 50, 75, and 100, and experiments are conducted according to the number of types of electronic components, number of nozzle types, and suitability between nozzles and electronic components, respectively. Because the experimental data are random, the calculation time is not constant, but it is confirmed that the gantry route is found within a reasonable time.

Managing and Minimizing Cost of Energy in Virtual Power Plants in the Presence of Plug-in Hybrid Electric Vehicles Considering Demand Response Program

  • Barati, Hassan;Ashir, Farshid
    • Journal of Electrical Engineering and Technology
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    • v.13 no.2
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    • pp.568-579
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    • 2018
  • Virtual power plants can be regarded as systems that have entered the network after restructure of power systems. In fact, these plants are a set of consumers capable of consuming and generating power. In response to widespread implementation of plug-in hybrid electric vehicles, further investigation of energy management in this type of power plants seems to be of great value. In effect, these vehicles are able to receive and inject power from/into the network. Hence, study of the effects of these vehicles on management of virtual power plants seems to be illuminative. In this paper, management of power consumption/generation in virtual power plants has been investigated in the presence of hybrid electric vehicles. The objective function of virtual power plants problem management is to minimize the overall costs including not only the costs of energy production in power generation units, fuels, and degradation of batteries of vehicles, but also the costs of purchasing electricity from the network. Furthermore, the constraints on the operational of plants, loads and hybrid vehicles, level of penalty for greenhouse gas emissions ($CO_2$ and $NO_x$) produced by power plants and vehicles, and demand response to the immediate price of market have all been attended to in the present study. GAMS/Cplex software system and sample power system have been employed to pursue computer implementation and simulation.

Influence of Interiorlandscape in Commercial Spaces on the Management Benefits (상업공간 실내조경이 경영적 효과에 미치는 영향)

  • 김수연;이종석
    • Journal of the Korean Institute of Landscape Architecture
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    • v.28 no.2
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    • pp.1-9
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    • 2000
  • The purpose of this study is to examine influence of interior landscape in commercial spaces on the management benefit. In the course of this study, objects of survey were selected from interior landscaping specialist, manager and consumer who had experiences to visit to the hotel, bank, department store and restaurant. The main method of data collection was interview, questions and gathering materials. The cronbach's alphas program was used to measure the reliability of likert scales. The analysis program was applied a statistical methods. The results of this study can be summarized as follows: The factors considered by consumer who visits to the commercial space are design, interior landscape, traffic, parking capacity, cleanness, price, kindness of employee and event. Factors concerned with the product include branch size, traffic, parking capacity, kindness of employee. Factors concerned with facilities include branch size, traffic, parking capacity, kindness of employee. Major factors of those effects to management benefit are accessibility, time of stay, sales, efficiency of space, attractiveness and difference. In conclusion, overlap style gets the highest degree of satisfaction among total factors. Results of the survey show that factors which improve sales are overlap style and planter type. Among four commercial spaces, hotel is most effected by interior landscape. To enhance the sales of hotel, further study of interior landscape about hotel necessary. For bank and restaurant, further study of economic planter type and style is necessary. For department store, optimal use of spaces and case of maintenance are necessary.

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A Study on Modeling of Users a Load Usage Pattern in Home Energy Management System Using a Copula Function and the Application (Copula 함수를 이용한 HEMS 내 전력소비자의 부하 사용패턴 모델링 및 그 적용에 관한 연구)

  • Shin, Je-Seok;Kim, Jin-O
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.1
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    • pp.16-22
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    • 2016
  • This paper addresses the load usage scheduling in the HEMS for residential power consumers. The HEMS would lead the residential users to change their power usage, so as to minimize the cost in response to external information such as a time-varying electricity price, the outside temperature. However, there may be a consumer's inconvenience in the change of the power usage. In order to improve this, it is required to understand the pattern of load usage according to the external information. Therefore, this paper suggests a methodology to model the load usage pattern, which classifies home appliances according to external information affecting the load usage and models the usage pattern for each appliance based on a copula function representing the correlation between variables. The modeled pattern would be reflected as a constraint condition for an optimal load usage scheduling problem in HEMS. To explain an application of the methodology, a case study is performed on an electrical water heater (EWH) and an optimal load usage scheduling for EHW is performed based on the branch-and-bound method. From the case study, it is shown that the load usage pattern can contribute to an efficient power consumption.

A Route-Splitting Approach to the Vehicle Routing Problem (차량경로문제의 경로분할모형에 관한 연구)

  • Kang, Sung-Min
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2005.10a
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    • pp.57-78
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    • 2005
  • The vehicle routing problem (VRP) is to determine a set of feasible vehicle routes, one for each vehicle, such that each customer is visited exactly once and the total distance travelled by the vehicles is minimized. A feasible route is defined as a simple circuit including the depot such that the total demand of the customers in the route does not exceed the vehicle capacity. While there have been significant advances recently in exact solution methodology, the VRP is not a well solved problem. We find most approaches still relying on the branch and bound method. These approaches employ various methodologies to compute a lower bound on the optimal value. We introduce a new modelling approach, termed route-splitting, for the VRP that allows us to address problems whose size is beyond the current computational range of set-partitioning models. The route-splitting model splits each vehicle route into segments, and results in more tractable subproblems. Lifting much of the burden of solving combinatorially hard subproblems, the route-splitting approach puts more weight on the LP master problem, Recent breakthroughs in solving LP problems (Nemhauser, 1994) bode well for our approach. Lower bounds are computed on five symmetric VRPs with up to 199 customers, and eight asymmetric VRPs with up to 70 customers. while it is said that the exact methods developed for asymmetric instances have in general a poor performance when applied to symmetric ones (Toth and Vigo, 2002), the route splitting approach shows a competent performance of 93.5% on average in the symmetric VRPs. For the asymmetric ones, the approach comes up with lower bounds of 97.6% on average. The route-splitting model can deal with asymmetric cost matrices and non-identical vehicles. Given the ability of the route-splitting model to address a wider range of applications and its good performance on asymmetric instances, we find the model promising and valuable for further research.

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Study on the Relationship between Brand Characteristics and Localization Strategy of Imported Brands in Korean Market (국내 수입브랜드의 특성과 현지화전략과의 관계연구)

  • Han, Jee-Hee;Ko, Eun-Ju
    • Journal of the Korean Society of Clothing and Textiles
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    • v.31 no.8
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    • pp.1180-1189
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    • 2007
  • The purpose of this study is to search the level of localization strategy of imported brands in Korean Market, to investigate relationship between the brand characteristics and localization strategy, and to study the case about localization strategy of the brand selected according to the type of brand. The survey research was employed and for the data analysis, descriptive statistics, one-way ANOVA, and multiple-regression were used. For the case study, interview with the person who works in the each kind of company was used. The results of this study were as follows: Firstly, the level of localization strategy is found in order price, place, promotion and product. Secondly among the brand characteristics, type of brand, proportion of garments, price zone, launching time, number of shop are related with localization strategy, but turnover and number of the staff are not. Thirdly, license brand has the characteristics like as national brands and the differences between the branch and the agent is confidence and communication that are the basic elements of localization. This study can help national brands to refer the localization strategy and provide the understanding of localization strategy of imported brands in Korean fashion market.

Tax Avoidance and Corporate Risk: Evidence from a Market Facing Economic Sanction Country

  • SALEHI, Mahdi;KHAZAEI, Sharbanoo;TARIGHI, Hossein
    • The Journal of Asian Finance, Economics and Business
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    • v.6 no.4
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    • pp.45-52
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    • 2019
  • The current study aims to investigate the relationship between tax avoidance and firm risk in an emerging market called Iran. The study population consists of 400 observations and 80 companies listed on the Tehran Stock Exchange (TSE) over a five-year period during 2012 and 2016. The statistical model used in this study is a multivariate regression model; besides, the statistical technique used to test the hypotheses proposed in this research is panel data. The results showed that low effective tax rate (tax avoidance) is more consistent than the higher effective tax rate. Moreover, there is no significant relationship between tax avoidance and future tax rate volatility. The findings also proved that lower effective tax rates are positively associated with future stock price volatility. This implies that since Iranian firms have many financial problems because of economic sanctions, they have a tendency to delay the disclosure of bad news about their firms. Needless to say, when a huge number of negative news reaches its peak, they immediately will enter the market and lead to a remarkable fluctuation in stock prices.