This study proposes a mathematical model to optimize the fighter aircraft-weapon combinations for the ROKAF(Republic Of Korea Air Force). With the recent emergence of the population declining issue in Republic of Korea, there is an urgent need for efficient weapon system operations in light of decreasing military personnel. In order to solve these issues, we consider to reduce the workload of pilots and maintenance personnel by operating an optimal number of weapons instead of deploying all possible armaments for each aircraft type. To achieve this, various factors for optimizing the fighter-weapon combinations were identified and quantified. A model was then constructed using goal programming, with the objective functions based on the compatibility, CEP(Circular Error Probable), and fire range of the weapons, along with the planned wartime mission-specific weapon ratios for each aircraft type. The experimental result's analysis of the proposed model indicate a significant increase in mission performance efficiency compared to the existing system in both operational and maintenance aspects. We hope that our model will be reflected to help improve the operational capabilities of Republic of Korea Air Force.
Sustainable development is a critical global priority, as showed by United Nations' Sustainable Development Goals (SDGs). Effective logistics are crucial for achieving several SDGs so that improvements in Logistics Performance Index (LPI) often align with progress in SDG scores. For ASEAN countries, they may fall short of achieving 90% of their targeted SDGs and struggle to challenges of LPI fluctuations. By calculating the correlation between LPI and SDG scores in R software, this study seeks to explore the relationship between logistics performance and progress toward the SDGs in ASEAN countries from 64 secondary observations. As a result, the increasing logistics performance can greatly impact on the population well-being, accessibility, new energy approach, infrastructure formation, and sustainable production and consumption (G1, G3, G7, G9, G12) in ASEAN countries. The study contributes a background for national policymakers in the region to develop the sustainable logistics.
Sequential zone picking is an order picking method designed to enhance warehouse efficiency by dividing the storage area into multiple zones and picking items in a sequential order across these zones. Picked items are often placed in dedicated totes and transported between zones using a conveyor system, which manages the picking flow but can occasionally result in inefficiencies during the process. This study presents a variant of the sequential zone picking system, called a dual-lane zone picking system (DZP), which consists of two parallel conveyor lanes without buffers between consecutive zones. This conveyor configuration allows the picker in each zone to alternate processing between the two lanes, thereby lessening the constraints of tote transitions between zones and improving both system throughput and picker utilization. We design and conduct a series of experiments using a discrete-event simulation model to evaluate the performance of DZPs. The experiment results indicate that DZP surpasses the original single-lane zone picking system by shortening the system’s mean flow time in low flow intensity scenarios and achieving a higher maximum throughput and worker utilization in high flow intensity scenarios. Additionally, we investigate the effects of the number of zones and order batching size on the performance of DZP to gain further insights into the system’s operational control.
This study proposes a mathematical model to optimize the fighter aircraft-weapon combinations for the Republic of Korea Air Force. With the recent emergence of the population cliff issue due to declining birth rates in Korea, there is an urgent need for efficient weapon system operations in light of decreasing military personnel. This study aims to enhance operational environments and mission efficiency within the military. The objective is to reduce the workload of pilots and maintenance personnel by operating an optimal number of weapons instead of deploying all possible armaments for each aircraft type. To achieve this, various factors for optimizing the fighter-weapon combinations were identified and quantified. A model was then constructed using goal programming, with the objective functions based on the compatibility, Circular Error Probable (CEP), and fire range of the weapons, along with the planned wartime mission-specific weapon ratios for each aircraft type. Experimental analysis of the proposed model indicated a significant increase in mission performance efficiency compared to the existing system in both operational and maintenance aspects. It is hoped that this model will be applied in military settings.
The era of logistics 4.0 in which new technologies are applied to existing traditional logistics management has approached. It is developing based on the convergence between various technologies, and R&D are being conducted worldwide to build smart logistics by synchronizing various services with the logistics industry. Therefore, this study proposes a methodology and technology strategy that can achieve trend analysis using patent analysis and promote the development of the domestic smart logistics industry based on this. Based on the preceding research, eight key technology fields related to smart logistics were selected, and technology trends were derived through LDA techniques. After that, for the development of the domestic logistics industry, the strategy of the domestic smart logistics industry was derived based on analysis including technology capabilities. It proposed a growth plan in the field of big data and IoT in terms of artificial intelligence, autonomous vehicles, and marketability. This study confirmed smart logistics technologies by using LDA and quantitative indicators expressing the market and technology of patents in literature analysis-oriented research that mainly focused on trend analysis. It is expected that this method can also be applied to emerging logistics technologies in the future.
When a fire breaks out in a distribution center, it causes a lot of damage. And the most casualties are caused by Fire accidents. Therefore, training for fire prevention should be mandatory at the distribution center. Also, the contents of education should be different in room temperature warehouses and low temperature warehouses. Fire education in low-temperature warehouses should be more emphasized. This is because many fires occur in low-temperature warehouses. In this study, a study was conducted to determine the important order of training hours and contents for fire prevention education according to the type of distribution center. The importance of time and content for safety education in all types of warehouses did not differ significantly. It was first decided that safety prevention training should be conducted periodically in all types of warehouses
ROK Navy Landing Ship Fast(LSF-II) is equipped with special equipment that is not compatible with other combat ships due to special missions. So there are almost no maintenance capabilities except for simple repair parts replacement and maintenance parts. The researcher determined that the way to solve these problems was to apply Performance Based Logistics (PBL), and reviewed the cases of PBL applications abroad and domestically. To confirm the current maintenance capability, we visited LSF-II operation unit to identify maintenance capabilities for each mounted equipment, and interviews with operators and maintenance practitioners confirmed the limitations of outsourcing maintenance and the need to apply PBL. In order to analyze the effect of PBL application, the measure of effectiveness and measure of performance were selected based on the opinions of LSF-II operation/maintenance practitioners and PBL experts and the practical experience of this researcher. A survey was conducted on operation/maintenance practitioners and professional personnel. Based on the survey results, the effect of applying PBL was analyzed using the AHP technique, and an efficient PBL application plan was proposed for LSF-II.
Industrial complexes are areas where manufacturing companies are integrated, and logistics between tenant companies play a very important role, but idle resources can occur depending on the situation if each company operates independently. Accordingly, this study aimed to reduce overall logistics costs and increase corporate productivity by looking at ways to share and utilize logistics resources such as warehouses and transportation equipment to efficiently utilize logistics resources in industrial complexes and implementing a logistics sharing platform that can share these idle resources. To this end, this study conducted a research survey on the logistics status of manufacturing companies in Ulsan-Mipo Industrial Complex, based on this analysis, the necessity of logistics resource types and utilization of industrial complex resident companies, and based on this, a service model for logistics resource sharing was studied. In addition, it was intended to analyze the operational characteristics of the existing logistics system to derive improvements and to derive optimal measures to utilize information on shared idle resources. This study confirmed the importance of sharing and utilizing idle resources to optimize logistics resources in industrial complexes, and is expected to contribute to reducing logistics costs and increasing logistics efficiency of tenant companies.
In the era of the 4th Industrial Revolution, Logistic 4.0 using data-based technologies such as IoT, Bigdata, and AI is a keystone to logistics intelligence. In particular, the AI technology such as prognostics and health management for the maintenance of logistics facilities is being in the spotlight. In order to ensure the reliability of the facilities, Time-Based Maintenance (TBM) can be performed in every certain period of time, but this causes excessive maintenance costs and has limitations in preventing sudden failures and accidents. On the other hand, the predictive maintenance using AI fault diagnosis model can do not only overcome the limitation of TBM by automatically detecting abnormalities in logistics facilities, but also offer more advantages by predicting future failures and allowing proactive measures to ensure stable and reliable system management. In order to train and predict with AI machine learning model, data needs to be collected, processed, and analyzed. In this study, we have develop a system that utilizes an AI detection model that can detect abnormalities of logistics rotational equipment and diagnose their fault types. In the discussion, we will explain the entire experimental processes : experimental design, data collection procedure, signal processing methods, feature analysis methods, and the model development.
In an automotive plant, an automated storage and retrieval system (ASRS) synchronizes material handling flows from a part production line to an auto-assembly line. The part production line transfers parts on small-/large-sized pallets. The products on pallets are temporarily stored on the ASRS, and the ASRS retrieves the products upon request from the auto-assembly line. Each ASRS aisle is equipped with narrow-/wide-width racks for two pallet sizes. An ASRS aisle with narrow-/wide-width racks improves both storage space utilization and crane utilization while requiring delicate ASRS aisle design, i.e., the locations of the narrow-/wide-width racks in an ASRS aisle, and proper operation policies affect the ASRS performance over demand fluctuations. We focus on operation policies involving a common storage zone using wide-width racks for two pallet sizes and a storage-retrieval job-change for a crane based on assembly-line batch size. We model a discrete-event simulation model and conduct extensive experiments to evaluate operation policies. The simulation results address the best ASRS aisle design and suggest the most effective operation policies for the aisle design.
Many manufacturers applying third party logistics (3PLs) have some challenges to increase their logistics efficiency. This study introduces an effort to estimate the weight of the delivery trucks provided by 3PL providers, which allows the manufacturer to package and load products in trailers in advance to reduce delivery time. The accuracy of the weigh estimation is more important due to the total weight regulation. This study uses not only the data from the company but also many general prediction variables such as weather, oil prices and population of destinations. In addition, operational statistics variables are developed to indicate the availabilities of the trucks in a specific weight category for each 3PL provider. The prediction model using XGBoost regressor and permutation feature importance method provides highly acceptable performance with MAPE of 2.785% and shows the effectiveness of the developed operational statistics variables.
한국통합물류협회의 발표에 따르면, 2021년도 국내 총 택배 물량은 33억 7천만 개로 전년대비 7.59% 증가했고 매출액은 8조 5,800억 원으로 전년대비 14.6% 증가한 것으로 나타났으며 이러한 증가추세는 향후 지속될 것으로 전망된다. 이러한 택배 물량을 처리함에 있어 작업자는 대표적인 근골격계 부담작업에 노출되어 각종 근골격계 질환 유발 및 능률 저하가 갈수록 심화되고 있는 상황이다. 이에 따라 최신 통신네트워크 기술을 기반으로 하여 작업자와 자율주행 무인 운반차(Automated Guided Vehicle, AGV) 그리고 로봇의 협업을 지원하기 위한 기술개발에 대한 관심이 고조되고 있다. 본 연구에서는 LTE / 5G와 같은 최신 통신네트워크 환경 하에서 물류센터에서 자율주행하면서 택배의 상/하차 작업을 수행하는 Horizontal Scissor Lift를 갖는 AGV를 개발하고 택배 분류작업을 수행하는 로봇이 AGV와 협업을 가능하도록 하여 물류 집하 및 분배 작업이 통합된 물류 자동화 플랫폼을 구축한다. 본 물류 자동화 플랫폼은 자율 주행하면서 택배를 상/하차 하는 Scissor Lift-type AGV, 택배 분류를 위한 로봇, 다수의 AGV의 충돌을 방지하고 작업지시 및 작업상태 확인, 작업결과 피드백 등의 실시간 모니터링을 위한 관제 시스템 등으로 구성된다. 특히, 본 논문에서는 Horizontal Scissor Lift를 갖는 AGV의 구체적인 설계 및 해석결과를 제시하고, AGV 시제품에 대해 이동속도, 긴급 제동거리 및 위치정밀도에 대한 성능 평가를 수행함으로써 개발되는 AGV 시스템의 성능을 검증한다.
From 1970 to 1990, North Korea’s trade mainly carried out maritime trade through ports for countries around the world. This trend is due to UN sanctions against North Korea, and after the third nuclear test in 2016, North Korea gradually became isolated from the outside world as it expanded to include maritime sanctions in the form of comprehensive sanctions targeting an unspecified majority of North Korea. The logistics structure of North Korea is due to the logistics infrastructure left during the Japanese colonial period in the 1950s and the political structure of the country, with railroads being the main source of logistics and passenger transportation, and roads being secondary. North Korea faced rapid deterioration and lack of facilities after 1990 due to the lack of investment in facilities and improvement of the operating system despite the advanced logistics infrastructure and operating system compared to the South. In particular, the power shortage in North Korea hindered the operation of the railroad and accelerated the aging of the railroad facilities, which has continued to this day. In the 2010s, 96% of cargo transportation in North Korea’s logistics infrastructure depended on railroads and roads, and ports that were developed until the 1980s have deteriorated with little investment since the economic crisis of the 1990s. Although some ports have been developed since 2010, North Korea’s east and west coasts are separated and there is no function of shipping to connect ports, so it did not have a significant impact on enhancing the nation’s port capacity. As North Korea’s trade dependence on China has increased, North Korea has largely relied on land transport, except for some cargoes that are advantageous for marine transport, such as coal. This structure again leads to a decrease in investment in ports, and the current vicious cycle of causing problems with North Korean port facilities is repeated. In this study, North Korea’s land and marine trade logistics system such as railway, road, and shipping and the trend of foreign trade due to sanctions against North Korea were analyzed. Through this analysis, it is planned to be used as a basis for developing the routes and scenarios through which major nuclear items can be transferred in the event of denuclearization of North Korea in the future.
The growth of the online market is accelerating due to the development of technology and the pandemic era. The delivery service through the courier must be used to deliver the ordered goods to the customer through the online market. With the growth of the online market, the logistics market for delivery is also growing. The traffic and environmental problems are emerging as social issues. Urban logistics technology using underground space based on the urban railway developed to improve logistics efficiency in a metropolitan area and a new alternative to environmental problems. This study proposed a plan to secure system safety through safety analysis based on operational concept definition and scenario analysis by applying model-based perspective analysis to the system under development.
농촌 종점 물류는 농촌 주민들의 온라인 쇼핑에 영향을 주는 중요한 요인임. 농촌 인터넷 쇼핑의 서비스 품질은 양호한 종점 물류 배송과 지원이 필요함. 농촌 이커머스의 발전에 의 하여 농촌 주민들이 서비스의 품질에 대한 기대치도 높아지고 있음. 본 연구에서는 이커머스 만족도를 통한 농촌 종점 물류 서비스 품질이 농촌 주민의 온라인 구매행위에 어떠한 영향 미치는지 검토하고, 농촌 종점 물류 서비스의 발전을 위한 개 선 및 발전전략을 제시하였음. 본 연구에서는 구조방정식모델 (SEM)과 온충린의 매개효과 테스트를 적용하여 분석하였음. 1. 신뢰성과 서비스 편의성은 만족도에 긍정적 영향을 미치며, 원가절약은 만족도에 부정적 영향을 미침. 2. 만족도는 인터넷 쇼핑에 긍정적인 영향을 미치는 것으로 나타났음. 3. 만족도는 반응성과 구매행위 사이에 매개효과가 있고 경제와 구매행위 사이에도 매개효과가 있는 것으로 나타났음.
Automated Guided Vehicle (AGV) is commonly used in manufacturing plant, warehouse, distribution center, and terminal. AGV is self-driven vehicle used to transport material between workstations in the shop floor without the help of an operator, and AGV includes a material transfer system located on the top and driving system at the bottom to move the vehicle as desired. For navigation, AGV mostly uses lane paths, signal paths or signal beacons. Various predominant sensors are also used in the AGV. However, in the conventional AGV, there is a problem of not turning or damaging nearby objects or AGV in a narrow space. In this paper, a new driving system is proposed to move the vehicle in a narrow space. In the proposed driving system, two sets of the combined steering-drive unit are adopted to solve the above problem. A prototype of AGV with the new driving system is developed for the comparative analysis with the conventional AGV. In addition, the experimental result shows the improved performance of the new driving system in the maximum speed, braking distance and positioning precision tests.