As the number of enlistees decreases due to social changes like declining birth rates, it is necessary to conduct research on the appropriate recalculation of the force that considers the future defense sufficiency and sustainability of the Army. However, existing research has primarily focused on qualitative studies based on comprehensive evaluations and expert opinions, lacking consideration of sustained support activities. Due to these limitations, there is a high possibility of differing opinions depending on perspectives and changes over time. In this study, we propose a quantitative method to calculate the proper personnel by applying system dynamics. For this purpose, we consider a standing army that can ensure the sufficiency of defense between battles over time as an adequate force and use battle damage calculated by wargame simulation as input data. The output data is the number of troops required to support activities, taking into account maintenance time, complexity, and difficulty. This study is the first quantitative attempt to calculate the appropriate standing army to keep the defense sufficiency of the ROK Army in 2040, and it is expected to serve as a cornerstone for adding logical and rational diversity to the qualitative force calculation studies that have been conducted so far.

By the recent fast growth of e-commerce markets, it has been stimulated to study order picking systems to improve their efficiency in distribution centers. Many companies and researchers have been developed various types of order picking systems and pursued the corresponding optimal operation policies. However, the performances of the systems with the optimal policies often depend on the structures of the centers and the operation environments. Based on a simulation model that mimics a unique zone picking system operated by a real company in the Republic of Korea, this study compares several operation policies and finds the most appropriate order selection rule and worker assignment policy for the system. Under all scenarios considered in this study, simulation results show that it is recommendable to assign more efficient workers to the zones with heavier workload. It also shows that selecting the order with the maximum number of non-repeatedly visited zones from the order list provides the most consistent and stable performances with respect to flow time, makespan, and utilization of the system even under the scenario with the breakdown zones. On the other hand, selecting the order with the minimum ratio of penalty to the number of zones performs the worst in all scenarios considered.

감사청구제도는 감사를 통해 국민 권익을 보호하기 위한 제도이다. 이 러한 감사를 통해 공공부문의 도덕적 해이나 부정 등에 관한 사항을 적 발하게 되면서 감사의 역할과 기능에 대한 관심이 고조되고 있다. 특히, 감사에 의해 공공기관의 책임행정을 구현한다는 목적에 따라 감사의 의 미는 더욱 중요해지고 있다. 그러나 국민의 신문고로서 역향을 수행할 것으로 기대하고 있는 감사청구제도에서 본 연구의 목적은 국민감사청구 제도와 공익감사청구제도 간 제도적 통합에 관한 근거를 제시하는 것이 다. 물론 기존 연구에서 두 제도 간 통합에 관한 제언을 하였으나 그에 대한 구체적 근거가 부족하고 원활한 감사청구제도를 위해 본 연구가 진 행되었다. 통합에 대한 논리적 근거로서 절차집행의 우선성, 법률적용의 확장성, 제도운용의 적절성을 제시하였다. 즉, 국민감사청구와 공익감사 청구가 운영 법률이 상이하긴 하나, 실제로 동일한 기능을 수행하고 있 고 청구인의 기준 및 청구대상 요건이 유사하다는 점이다. 또한 운영현 황에 있어 국민감사청구제도보다 공익감사청구제도가 상대적으로 원활하 게 운영되고 있다는 점이다.

We analyzed risk factors of coastal gillnet fishers during fishing process and considered work safety measures to reduce safety accidents during fishing using a UWB (ultra wideband) based positioning system. The static position accuracy of the UWB based positioning system was 45 cm. When entering a port, there is a risk of falling overboard. When casting a net, there was a risk of falling overboard due to being hit by fishing gear or guards, or getting caught in a buoy line or sinker line. When hauling a net, there is a risk of getting caught between fishing gear and net hauler, and the risk of musculoskeletal disorders due to repetitive work over a long period of time. Most safety accidents during work on fishing boats are blamed on human errors of the fisher and skipper, but safety accidents occur due to a mixture of mechanical and equipment factors, work and environmental factors, and management factors in addition to human errors. Therefore, the 4E were presented as countermeasures against the 4M, which are causes of safety accidents, and the proposed measures were used to identify risk factors for operation process, comply with work safety rules, and ensure the wearing of personal protective equipments. We need to reduce safety accidents during work by making it part of our daily routine. These research results can be used in the future for optimal placement of fishing gear and fishing nets in other coastal industries where safety accidents occur frequently.

The purpose of this study was to propose an operational concept for a ship in a fleet equipped with an interceptor missile system, a naval surface to air defense system, and to develop a simulation program that reflects it. The results of the defense activities of other ships in the fleet can be reflected by receiving information about the status of the enemy missiles. The allocation of defensive assets is based on the survival probability of the ship, not on the destruction of enemy attacks, which can be obtained as the product of the expected survival probability for each enemy missile. In addition, the concept of predicted survivability was introduced to assess the loss of future defense opportunities that would result from assigning a new command. A simulation program was also developed as a tool for realizing the proposed concept of operations, which generated cases.

PURPOSES : The number of snowfall and the amount of snowfall are gradually increasing, and due to the characteristics of Seoul, which has a lot of traffic, it is difficult to respond quickly with a snow removal method that relies on snow removal vehicles. Therefore, it is necessary to develop an IoT based eco-friendly snow removal system that can respond to unexpected heavy snow in winter. In this study, the low temperature operation and snow removal performance of the IoT road condition snow removal detector and the snow removal system using CNT and PCM are evaluated in the climatic environment chamber. METHODS : To make artificial snow, it consists of an climatic environment chamber that can simulate a low temperature environment and equipment that can supply compressed air and cold water. Depending on the usage characteristics of the climatic environment chamber, use an air-water type snow maker. In order to make artificial snow, wet temperature, which takes into account the actual air temperature and the amount of moisture in the air, acts as the most important variable and is suitable for making snow, below –1.5 ℃. The lower the water temperature, the easier it is to freeze, so the water source was continuously supplied at 0 ℃ to 4 ℃. One of the two different pipes is connected to the water tank to supply water, and the other pipe is connected to the compressor to supply high-pressure air. Water is dispersed by compressed air in the form of many small droplets. The sprayed microscopic water particles freeze quickly in the low temperature environmental climatic chamber air and naturally fall to the floor, forming snow. Based on the KS C IEC 60068-2-1 cold resistance test standard, an integrated environmental test procedure was prepared to apply to IoT-based snow removal systems and performance evaluation was performed accordingly. The IoT based eco-friendly snow removal system is needed to in winter, so visual check and inspect the operation at the climatic chamber before setting up it to the actual site. In addition, grid type equipment was manufactured for consistent and reliable snow removal performance evaluation under controlled environmental conditions. RESULTS : The IoT-based eco-friendly snow removal system normally carried out the task of acquiring data and images without damaging the appearance or freezing in a low temperature environment. It showed clear snow removal performance in areas where PCM and CNT heating technology were applied to the concrete slab. This experiment shows that normal snow removal tasks can be carried out in low temperature environments in winter. CONCLUSIONS : The integrated environmental test procedures and grid type evaluation equipment are applied to low temperature operation and snow removal performance evaluation of snow removal systems. In the climatic environment chamber, where low temperature environments can be simulated, artificial snow is created regardless of the season to derive quantitative experimental results on snow removal performance. PCM and CNT heating technology showed high snow removal performance. The system is expected to be applied to road site situations to preemptively respond to unexpected heavy snow in winter.

KAERI has developed a Radioactive Waste Information Management System (RAWINGS) to manage the life-cycle information from the generation to the disposal of radioactive waste, in compliance with the low- and medium-level radioactive waste acceptance criteria (WAC). In the radioactive waste management process, the preceding steps are to receive waste history from the waste generators. This includes an application for a specified container with a QR label, pre-inspection, and management request. Next, the succeeding steps consist of repackaging, treatment, characterization, and evaluating the suitability of disposal, for a process to transparently manage radioactive wastes. Since the system operated in 2021, The system is enhanced to manage dynamic information, including the tracking of the location of radioactive waste and the repackaging process. Small packages of waste could be classified as either radioactive or clearance waste during pre-inspection. Furthermore, waste generated in the past has already been packaged in drums, and a new algorithm has been developed to apply the repackaging when reclassification is required. All radioactive waste with the unique ID number on the specific container is managed within a database, the total amount and history of waste are managed, and statistical information is provided. This system is continuously be operated and developed to oversee life-cycle information, and serve as the foundational database for the Waste Certification Program (WCP).

Among domestic Nuclear Power Plants (NPPs), there are a total of 10 nuclear power plants whose operating license expires by 2030, excluding Kori unit 1 and Wolsong unit 1, which are permanently shut downed. Continued operation of these nuclear power plants is being reviewed as a government task. For continued operation, nuclear power plant owners must prepare periodic safety review and other evaluation reports to receive reviews to maintain safety even during continued operation. In the safety evaluation of NPP, it is important to refer to overseas cases and operation experiences. In this study, the matters of radioactive waste management for continued operation of NPP was considered by analyzing the safety evaluation reports and safety enhancements of license renewal of NPP in USA, Radioactive waste generated from NPPs can be classified into solid, liquid, and gaseous states. Radioactive waste generated during the operation and maintenance of power plants is classified, stored and treated in the radioactive waste management system according to the source. Equipment and monitors related to radioactive waste management are continuously operated, managed, inspected according to standards and maintain their original functions. Various activities to reduce the generation and emission of radioactive waste from NPPs are performed. After reviewing the NRC’s safety evaluation report on the application documents for license renewal of US NPPs (Sequoyah, Byron and braidwood) the evaluation details and matters requiring enhancement for the radioactive waste management system were confirmed. As a major check, selective leaching occurred in the body of the gray cast iron valve and the heat exchanger shell containing the copper alloy exposed to the radioactive waste liquid. Selective leaching causes loss of material and may interfere with the original function of the facility, so management is required. For the safe operation and management of NPPs, it is important to refer to overseas cases and experiences. Among the safety evaluations for the continued operation of domestic NPPs, in the field of the radioactive waste management system, if the case of the US NPP is referred to, the review by the regulatory body and the action taken by the licensee will be more efficient.

The need for an intelligent information-based ship accident prevention and control system for various marine accidents is very clearly emerging. As it is a variety of marine accidents, the causes are diverse. Therefore, it can be said that it is very important to prevent these marine accidents and their causes in advance. Therefore, a study was conducted on an intelligent information-based ship safety management decision support system that provides information necessary for decision-making at sea and land through an integrated management device for ships that informs safety-related risks in real-time ship operation. In the future, we intend to pursue the development of a system that can aim for safer and more economical ship operation by linking it to navigation instruments through the evaluation and analysis of AI, IoT, and big data.

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.

자율운항선박(MASS : Maritime Autonomous Surface Ships)은, 고도의 자율도를 가지고, 계획된 경로를 따라 자율 운항하지만, 필요시 육상원격제어센터(SRCC : Shore Remote Control Center)에서 선박의 운항에 직접 개입할 수 있다. 본 연구에서는 이러한 자율운항 선박의 운항을 육상에서 모니터링하고 유사시 원격제어하는 역할을 담당할 육상원격제어사(SRCO : Shore Remote Control Officer)의 교육 훈련에 필요한 시뮬레이터 시스템의 운용개념과 이를 가능하게 하기 위한 요구기능에 대해 검토하였다. 육상원격제어 시뮬레이터 시 스템은, 다수의 자율운항선박의 운항상황을 모니터링하는 Monitoring Station, 유사시 특정 선박의 운항에 직접 원격개입하는 Control Station의 기능을 모의하도록 하였고, 시뮬레이션 종합통제실, 자율운항선박 운항상황 모의 시뮬레이터, 그리고 주변의 유인선 운항을 모의하기 위한 통항선 시뮬레이터 등으로 구성하였다. 기능적으로는, 육상에서 선박을 직접 제어하기 위하여 원격으로 개입하는 ESRC(Emergency Situation for Remote Control) 상황을 정의하여 이러한 상황을 모의할 수 있도록 하였다.

Despite the increasing interest in Deep Borehole Disposal (DBD) for its capability of minimizing disposal area, detailed research about DBD operation system design should be conducted before the DBD can be implemented. Recently, DBD operation system applying wireline emplacement (WE) technique is under study due to its high flexibility and capability of minimizing surface equipment. In this study, a conceptual WE system, and operation procdure is introduced. The conceptual WE system consists of 3 main stations, which from the top are hoisting station (HS), canister connection station (CCS) and basement (BS). In HS, WE is controlled and monitored. The WE is controlled using wireline drum winch and sheaves, and load on wireline is measured using a load cell. HS also has a pressure control system (PCS), which monitors internal pressure of the system, and a lubricator, which act as housing for joint device, allowing the joint device to be easily inserted into the borehole. The joint device is used to connect the disposal canister to wireline for emplacement/retrieval. In CCS, a rail transporter brings a transport cask containing disposal canisters, then the transport cask is connected to the hoisting system and a PCS in the BS. The main component located at canister station are a sliding shielding door (SSD), and a slip. The SSD is used to prevent canister from falling into borehole during the connecting operation and prevent radiation from BS to affect the workers. The slip is located beneath the SSD and is used to hold the disposal canister before it is lowered into the borehole. In BS, PCS is installed to prevent overflow and blowout of borehole fluid. The PCS consists of wireline pressure valve, christmas tree and BOP, which all are a type of pressure valve to seal the borehole and release pressure inside the borehole. The WE procedure starts with transporting transport cask to CCS. The transport cask is connected to lubricator, and PCS. Joint device is lowered down to be connected with disposal canisters, then pulled up to check the load on the wireline. After the check-up, SSD is opened, and disposal canister is lowered into the borehole. When desired depth is reached, joint device is disconnected and retrieved for next emplacement. In this study, the conceptual deep borehole disposal system design implementing WE technique is introduced. Based on this study, further detailed design could be derived in future, and feasibility could be tested.

The development of technology related to the Fourth Industrial Revolution and the growth of the online market due to pandemic are continuing the growth of the logistics market for product delivery. If it is difficult to deliver the product directly to the customer during delivery, storage and delivery using the unmanned courier box are being carried out. However, existing storage boxes are not actively used due to lack of usability even though they have the advantage of storing goods and delivering non-face-to-face. In addition, existing courier boxes are not prepared for cold chain transportation. The unmanned delivery storage device with ICT cold chain technology should be developed to prepare for the transition to non-face-to-face society, to improve logistics efficiency and meet user's requirements. Also, it is necessary to consider the measures to reduce the safety problems that may occur during the use and maintenance of the automatic system.This study conducted a model-based analysis for the development of unmanned delivery storage devices with ICT cold chain technology, and conducted a study to derive the system development specifications that meet the requirements and secure safety and apply them to the development process.

This study tried to suggest a systematic improvement plan to prepare a civil safety insurance operation and management system by reviewing the operation and management status of civil safety insurance, which is operated and managed by each local government autonomously. In this study, the problems of the current civil safety insurance were analyzed by dividing them into the lack of systematic management of insurance items, overlapping coverage between insurance items, and deviations in compensation limits. As a systematic improvement plan, it was suggested to secure the systemic management of guarantee items, standardize compensation standards, prepare an integrated operation and management system, and provide financial support for local governments with poor financial independence. Since the problems and improvement plans for the civil safety insurance analyzed as described above are formed by exchanging and receiving a complex mutual influence, the institutional improvement plan for the operation and management system of the civil safety insurance is not only a specific part of the study, but also comprehensively current citizens. Based on the results derived from the analysis of safety insurance, it is concluded that alternatives must be found.