A Genetic Algorithm Approach for Logistics Network Integrating Forward and Reverse Flows

고현정,고창성,정기호,Ko, Hyun-Jeung,Ko, Chang-Seong,Chung, Ki-Ho 대한산업공학회 2004 산업공학 Vol.17 No.S

As today's business environment has become more and more competitive, forward as well as backward flows of products among members belonging to a supply chain have been increased. The backward flows of products, which are common in most industries, result from increasing amount of products that are returned, recalled, or need to be repaired. Effective management for the backward flows of products has become an important issue for businesses because of opportunities for simultaneously enhancing profitability and customer satisfaction from returned products. Since third party logistics service providers (3PLs) are playing an important role in reverse logistics operations, they should perform two simultaneous logistics operations for a number of different clients who want to improve their logistics operations for both forward and reverse flows. In this case, distribution networks have been independently designed with respect to either forward or backward flows so far. This paper proposes a mixed integer programming model for the design of network integrating both forward and reverse logistics. Since the network design problem belongs to a class of NP-hard problems, we present an efficient heuristic algorithm based on genetic algorithm (GA), of which the performance is compared to the lower bound by Lagrangian relaxation. Finally, the validity of proposed algorithm is tested using numerical examples.

컨테이너터미널 운영사의 기업경쟁력 평가에 관한 연구

고현정,길광수,Ko, Hyun-Jeung,Kil, Kwang-Soo 한국항해항만학회 2011 한국항해항만학회지 Vol. No.

본 연구는 최근 우리나라 항만 물동량 증가세가 둔화되고 있는 가운데 국내 컨테이너터미널 운영기업의 경쟁력 강화를 위한 방안을 마련하고자 기업경쟁력 평가모형을 제시하고 글로벌 터미널 운영사와 비교분석하였다. 기업경쟁력 분석을 위한 퍼지모형은 퍼지이론과 AHP를 활용하였다. 경쟁력 평가를 위한 계층적 구조는 SERM 모형을 활용하였는바, 이는 기업의 성장이 주체(Subject), 환경(Environment), 자원(Resource), 그리고 메커니즘(Mechanism)의 상호작용 과정에서 형성된다는 논리에 바탕을 두고 있다. 분석결과 우리나라 컨테이너터미널 운영기업의 경쟁력은 글로벌 기업에 비해 전반적으로 약한 것으로 나타났다. 특히 기업의 대형화, 사업 다각화, 글로벌 전략수립이 시급한 것으로 나타났다. As the annual growth rate of port handling container volume in Korea has faced slowdown, this paper attempts to find strategies for the domestic container terminal operators in order to enhance competitiveness. For this, the model of using AHP and the fuzzy set theory is used for evaluating competitiveness between domestic and global container terminal operators. The evaluation model hierarchy is developed based on SERM(subject-environment-resource-mechanism) theory of business strategy. The results show domestic operators are ranked lower than global player so that they particularly pay attention to the areas of scale of economy, business diversification, and globalization strategy.

부가가치 극대화를 위한 새만금 신항의 발전방안에 관한 연구

고현정(Hyun-Jeung, Ko),조성우(Sung-Woo, Cho) 한국해양비즈니스학회 2012 해양비즈니스 Vol.- No.23

The aim of this study is to identify the current state of the Saemangeum New Port and understand the 'Trigger Rule' methodology that regularly examine throughput and port handling capacity, and then effectively respond the demand. We are going to suggest some ways for improvement and practical implications based on SWOT and SER-M analyses. The paper has suggested the feasible means for efficient development of Saemangeum New Port from the three perspectives. (1) customized model development of logistics business (2) long term planning (3) relationship between Gunsan Port and Saemangeum New Port(fuction sharing aspect). Finally, to establish the business model for enhancing a ripple effect is one of the critical factors in order to maintain the stable throughput and the long term development.

토픽 모델링을 활용한 라스트마일 배송의 논제 분석

고현정(Ko, Hyun Jeung),손영환(Sohn, Young Hwan) 한국상품학회 2021 商品學硏究 Vol.39 No.5

온라인 전자상거래의 발전과 코로나19 팬데믹시대에 라스트마일 배송의 수요가 증가하고 있다. 하지만 물류비용 측면에서는 비효율성이 높은 구간으로 수익성을 확보하기 위한 기술 혁신이나 다양한 전략이 요구된다. 따라서 본 연구에서는 토픽 모델링 기법을 적용하여 라스트마일 배송 관련 연구의 핵심 논제를 분석하여 새로운 시사점을 제공하고자 하였다. 연구 결과의 시사점은 다음과 같다. 첫째, 단어의 빈도 분석을 통해 라스트마일 배송은 고객, 시간, 비용이 중요한 키워드임을 확인하였다. 둘째, 단어의 유사도 분석을 통해 라스트마일 배송에서 특히 배송의 유연성이 중요하다는 것을 확인하였다. 셋째, LDA(Latent Dirichlet Allocation) 분석을 통해 다섯 가지 연구 논제, 디지털화(digitalziaton), 도심 물류(urban logistics), 풀필먼트(fullfillment), 노선 최적화(route optimization), 서비스 혁신(service innovation)으로 분류하였다. 넷째, IDM(Intertopic Distance Map) 분석을 통해 디지털화와 노선 최적화, 풀필먼트와 서비스 혁신이 각각 서로 인접하여 논제의 유사성이 있음을 확인하였다. 기존의 연구가 키워드나 초록 중심으로 이루어졌으나 본 연구는 논문의 본문을 포함하여 더 많은 텍스트 정보를 제공하여 새로운 통찰력을 제공하고 기존문헌을 보완하는측면에서 학술적 기여가 있을 것으로 기대된다. With the development of online e-commerce and the COVID-19 pandemic, the demand for last-mile delivery is increasing. However, the last-mile delivery is known as a section with high inefficiency in terms of logistics cost so that it requires technological innovation or various strategies to secure profitability. Therefore, in this study, the topic modeling technique was applied to analyze the key topics of the last mile delivery related research and to provide new implications. The implications of the study results are as follows. First, through word frequency analysis, customers, time, and cost were important keywords for last mile delivery. Second, through word similarity analysis, delivery flexibility was particularly important in last-mile delivery. Third, through LDA (Latent Dirichlet Allocation) analysis, it was classified into five research topics such as digitaliziaton, fulfillment, service innovation, route optimization, and urban logistics. Fourth, through IDM (Intertopic Distance Map) analysis, digitization and route optimization were adjacent to each other, and similarly fulfillment and service innovation were adjacent to each other. This confirmed that the topics were similar respectively. Although existing studies have focused on keywords or abstracts, this study provides more textual information by including the body of the research paper so that it can provide new insights and academic contributions in terms of supplementing existing literature.

환황해권 해상물류보안 협력방안에 관한 연구

고현정(Hyun-jeung Ko) 한국해양비즈니스학회 2014 해양비즈니스 Vol.- No.29

After the terrorist attack of 9/11 on the USA, the global logistics security has become an indispensable component of the international trade. In particular, Korea, China, and Japan where their total trade volume in the Pan Yellow Sea is regarded as about 20% of world trade volume are very trade dependent on each other. In addition, the ocean transit times between ports in the Pan Yellow Sea region are generally within 20 hours. This geographical feature makes the region hard to comply with the 24-Hour Rule which is one of global logistics security regulations. Thus, the purpose of this study is to explore the regional cooperation of shipping logistics security from Saemangeum point of view. Saemangeum is located in the center of the Pan Yellow Sea region, and it is a national project to build a global city as the front-runner of green growth. To this end, this paper suggested three basic principles for the regional cooperation, which were shorter transit time, costs savings, and emergency response actions. Based on such principles, this study proposed three cooperation policies. First, Saemangeum Green Lane cooperation among ports based on the predefined regional level of logistics security was suggested by which the participated ports could save not only the costs of systems investment but also the time of customs procedures. Second, the regional supply chain crime cooperation was addressed. This made the region share crime information so that the possible supply chain disruptions could be minimized. Third, the regional expert group on shipping logistics security was assembled in order to promote cooperation through the technical cooperation and capacity building, the training and eduction, and the discussion of common regional and global challenges. As a result, an efficient and secured seamless trade flow could ensured through the cooperation of the Pan Yellow region resulting in eliminating the logistics security barriers.

서남해안 2.5GW 해상풍력단지 조성을 위한 설치 일정계획

고현정(Ko, Hyun-Jeung) 한국항만경제학회 2017 韓國港灣經濟學會誌 Vol.33 No.2

지구 온난화에 대처하는 일환으로 신재생에너지 가운데 세계 각국은 해상풍력단지 개발에 투자를 집중하고 있다. 그러나 해상풍력단지 개발은 해상에서의 구조물 운송, 설치 등의 해상작업이 요구됨에 따라 투자비용이 육상풍력단지 보다 높은 단점이 있다. 특히 해상기상 여건으로 인한 설치기간 지연은 해상풍력단지 운영의 경제성에도 영향을 끼치는 요소이다. 따라서 본 연구에서는 국내 해상의 기상여건을 고려하여 해상풍력단지 조성의 최적 일정계획을 거시적 측면에서 분석하고자 하였다. 이를 위해 수리적 모델을 개발하였고, 이를 이용하여 국내 서남해안 2.5GW 해상풍력단지 조성사업에 적용하였다. 해상 기상여건은 기상청의 자료를 활용하였고, 모델에 사용된 입력 자료는 해외의 선행 사례를 바탕으로 현실성을 최대한 반영하고자 하였다. 그 결과 해상풍력터빈 35기를 설치하는데 6개월이 소요되는 것으로 분석되었다. 특히 겨울을 피하여 작업하는 것이 비용을 최소화할 수 있는 것으로 분석되었다. As a way to address global warming, among the renewable energy sources, there have been heavy investments worldwide for the development of offshore wind farms. However, such development has a drawback: investment costs are higher than those for onshore wind farms due to required operations such as offshore transportation and installation. In particular, delays in installation due to adverse maritime weather conditions are factors that affect the economics of offshore wind farms" operation. Therefore, in this study, we analyze the optimal schedule of the construction of an offshore wind farm from a macro perspective by considering the weather conditions in Korea. For this purpose, we develop a mathematical model and apply it to a 2.5 GW offshore wind farm project on the southwestern coast of the country. We use data from the Korea Meteorological Agency for maritime weather conditions and attempt to reflect the actual input data based on precedent cases overseas. The results show that it takes 6 months to install 35 offshore wind turbines. More specifically, it is pointed out that it is possible to minimize costs by not working in winter.

호남권 지역산업의 연결망 분석에 관한 연구 - 해상풍력산업을 중심으로 -

고현정 ( Ko Hyun-jeung ) 경남대학교 산업경영연구소 2024 지역산업연구 Vol.47 No.2

본 연구는 호남권의 해상풍력산업이 지역산업 활동에 미치는 영향을 파악하고자 사회연결망을 활용하였다. 이를 위해 지역산업연관표를 응용하여 단위구조 행렬을 도출하고 지역산업 연결망을 분석하였다. 특히 호남권을 전북과 전남을 구분하고 두 지역의 해상풍력산업이 지역경제에서의 위상과 다른 산업들과의 연계 관계를 비교하였다. 호남권 지역산업에 대한 연결망 중심성 분석은 연결중심성, 근접중심성, 매개중심성의 지표를 활용하였고 분석 결과 해상풍력산업이 모든 지표에서 타 산업보다 최상위에 위치하였다. 이는 해상풍력산업은 호남의 지역경제 발전에 중요하고 큰 영향력을 행사할 수 있다는 것을 확인할 수 있었다. 전북은 내향 연결중심성이 높고, 전남은 외향 연결중심성이 높았다. 해상풍력산업의 근접중심성 지표도 호남권에서 높았으며 이는 전북 및 전남에서 지역경제 활성화를 위한 시작점을 찾고자 할 때 유용하게 활용할 수 있다는 의미이다. 해상풍력산업의 매개중심성도 상위에 위치하여 타 지역산업의 경제활동에 대한 통제력이 높은 산업으로 나타났다. This study was aimed to understand the impact of the offshore wind power industry on local industrial activities in the Honam region through the use of social network analysis. For this purpose, the regional industrial network was analyzed by applying a unit structure matrix based on the regional input-output table. In particular, the Honam region was divided into Jeonbuk and Jeollanam-do, and the status of the offshore wind power industry in the two regions were compared with respect to the regional economy and their linkages with other industries. In addition, the network centrality analysis of regional industries was conducted base on the indicators of degree centrality, closeness centrality, and betweenness centrality. As a result, the offshore wind power industry was ranked higher other industries in all indicators. This implied that the offshore wind power industry is important and can have a great influence on the development of the Honam region's economy. In detail, Jeonbuk had high inward degreee centrality, and Jeonnam had high outward degree centrality. The closeness centrality of the offshore wind power industry was also high in the Honam region, which means that it can be useful when looking for a starting point for revitalizing the local economy. The betweenness centrality of the offshore wind power industry was also high, making it an industry with high control over the economic activities of other regional industries.

유전자 알고리즘을 이용한 해상풍력단지 조성에 관한 연구

고현정(Ko, Hyun-Jeung) 한국물류학회 2018 물류학회지 Vol.28 No.5

해상풍력단지 조성작업은 선박을 이용한 해상작업이 요구됨에 따라 해상의 기상여건에 매우 민감하다. 이는 해상여건이 악화 하면 해상풍력단지 완공 시기가 지연되면서 선박임대료, 인건비 등의 추가적인 비용이 발생하고, 궁극적으로 해상풍력단지 운영의 경제성에 영향을 끼치게 된다. 따라서 본 연구에서는 변화하는 해상여건에 따른 해상작업의 불확실성을 고려하여 해상풍력단지 조성에 관한 일정계획을 참고할 수 있는 분석모델을 개발하였다. 이를 위해 먼저 분석모델 구축을 위해 국내 해상풍력단지 조성을 위한 해상물류 프로세스를 정의하였다. 국내의 해상풍력단지 조성을 위한 해상물류는 항만을 중계지로 활용하는 체계이다. 항만에서 해상풍력 시스템의 구성품이 집화되고, 이를 반 조립한 후 선박을 이용하여 운송하고 해상에서 설치하는 방식이다. 다음 으로 정의된 해상물류 프로세스에 기초한 수리적 모델을 개발하였다. 또한, 개발된 수리적 모델이 NP-hard 문제에 속하므로 휴리 스틱 기법인 유전자 알고리즘을 개발하여 국내 서남해안 해상풍력단지 조성 프로젝트 사례에 적용하였다. 그 결과 해상풍력터빈 1기당 평균 설치작업 일수는 3.13∼3.29일로 분석되었다. 그리고 해상풍력 시스템의 설치 대수가 적으면 해저작업을 선행한 후 해상작업을 하는 것이 타당한 것으로 나타났다. 반면에 대규모의 해상풍력단지를 조성할 경우는 해상여건을 고려하여 전략적으로 일정을 관리하는 것이 필요한 것으로 분석되었다. The construction of offshore wind farms is very sensitive to the weather conditions due to the demand for maritime work using ships. If the delay of completion of offshore wind farm is occurred depending on the weather and marine conditions, additional costs will be incurred, which will eventually affect the economics of offshore wind farm operation. Therefore, in this study, we tried to developed a schedule analysis model for the construction of offshore wind farm considering the uncertainty of marine work according to the changing marine conditions. For this purpose, we firstly defined maritime logistics processes for the construction of offshore wind farms with respect to the situation in Korea. In fact, the maritime logistics system for the construction of offshore wind farms was a system that utilized ports as relay stations. The components of the offshore wind power system were collected in the port, semi-assembled, transported by ship, and installed at sea. Next, a mathematical model was developed based on the marine logistics process defined. In addition, since the developed mathematical model belonged to the NP-hard problem, the genetic algorithm was developed as an heuristic technique and applied to the example problem. As a result, the average installation work days per offshore wind turbine were analyzed to be 3.13∼3.29 days. If the number of offshore wind turbines to be installed was small, it was found that the submarine works were on the priority compared to the works above the water. On the other hand if the number was large, it was necessary to strategically adjust the work schedule of installing offshore wind turbines considering the maritime conditions.

서남해안 해상풍력단지 활성화를 위한 한중 협력방안 연구 -새만금을 중심으로-

고현정 ( Hyun Jeung Ko ),강태원 ( Tae Won Kang ) 아시아.유럽미래학회 2014 유라시아연구 Vol.11 No.4

Offshore wind power is increasingly getting attention from a number of countries since it is to not only easily find a vast area for the construction of wind farm but also minimize collective civil appeals of noise and vibration. Many countries such as UK, Denmark, Germany, China, etc thus are expanding their investment on it. Korea also aimed to foster offshore wind industry as the nation’s new growth engine and announced the project of a southwestern coast 2.5GW offshore wind farm. To facilitate the project, Korean government appointed Gunsan port for supporting the construction of the offshore wind farm, which is located in the Saemangeum area. In particular, the port will be expected to play the role of a logistics base for off-loading, storage, assembly and transportation of large-heavy wind turbines and sub-structures. In addition to the offshore wind port, offshore wind turbine related manufactures such as Hyundai Heavy Industrial Ltd. KM Co. Ltd. DACC Co. Ltd. etc have already been moved in the national industrial parks of Saemangeum-Gunsan region so that it has sufficient potential to be a strategic location for offshore wind power cluster. China has a goal to install over 10GW by 2020 according to the national plan of renewable energy development. In fact, China’s NEA(National Energy Administration) in 2009 requested 11 provincial governments along the east coast of China(Shanghai, Jiangsu, Zhejiang, Shandong, etc) to give in the plans of offshore wind development and finally established a national plan for large capacity offshore wind farms. In this regard, the offshore wind farms to be installed in the east coast of China are close to Saemangeum-Gunsan area so that this paper proposed three cooperation measures with respect to the Saemangeum’s geographical advantages. First, it is to build a cooperations system of Korea-China international specialization on offshore wind power. It is explained that Jeonbuk province where shipbuilding, offshore plant, and machine part manufactures have been already running their businesses has been placed increasing pressure to clarify policy around support, subsidies, and overall framework policies. Second, it is to use Gunsan port with sufficient hinterlands and water depth as a logistical base for Korea-China wind power farms since Korea government selected it as a offshore wind support port. Finally, it is to carry forward various China-Korea professional manpower training and exchange programs. There are a few centers for the development of new and renewable energy human resource in Jeonbuk area. Therefore, as the accumulation of knowledge and technology is needed in order to economically construct and operate the southwestern coast 2.5GWoffshore wind farm, this paper suggested a good way of cooperation with China and Korea for the development of offshore wind power industry and would finally support to help the development and facilitation of Saemangeum project.

우리나라 물류보안 인증제도 효율화 방안에 관한 연구

고현정 ( Hyun Jeung Ko ) 한국로지스틱스학회 2011 로지스틱스연구 Vol.19 No.2

9?11 이후 공급사슬에서의 보안확보가 부각되면서 글로벌 물류보안제도가 강화되고 있다. 물류보안 강화로 국제교역에서의 세밀한 화물검사 및 추가적인 정보교환절차가 요구됨에 따라 화물의 지체 현상이 발생된다. 이러한 문제점을 해결하고자 우리나라를 포함하여 각국은 국가물류보안 인증제도를 도입하여 효율적인 국제교역의 흐름을 보장하고 있다. 그러나 국내 기업들은 국내 물류보안 인증 제도 참여에 수동적 입장이다. 따라서 본 연구는 국내외에서 추진되고 있는 물류보안 인증제도의 장 단점을 분석하고 기업들의 요구사항을 파악하여 통합된 효율적 국가 물류보안 인증제도의 운영 방안 을 제시하였다. 주요 내용은 선택적 AEO(Authorized economic operator) 인증형태 운영, 보안전문 인력양성 및 교육프로그램 마련, 정부의 지원체계 마련, 국내 인증제도 효율적 연계를 제안하였다. 향후 국가의 물류보안 인증제도를 효율적으로 정착시키고 활성화하는데 기여할 것으로 사료된다. After the terrorist attack of 9/11 on the USA, the global logistics security has become an essential requirement for the successful running of business in the safeguarding of raw material, intermediary products, and finished goods during transportation and procurement. One of ways to facilitate international trade is to adopt the programs of logistics security assurances. In this regard, Korea is preparing the several security programs operated by various ministries for not only improving the efficiency of trade flows but also ensuring logistics security. However, many companies are expressing the inefficiency of operating such programs. Thus, this paper analyzed logistics security assurance programs adopted in domestic and foreign countries and suggested policy recommendations for improving the efficiency of the national logistics security system.