지하도로는 주변 도심개발 등으로 수평적 도로용량 확장이 어려운 구간을 대상으로 입체적 활용을 통해 교통혼잡을 해소하기 위한 수단으로써 주목받고 있다. 그러나 지하도로는 공간 특성상 지상에 비해 다양한 불확실성이 수반된다는 면에서 위험요인이 크고 직접 건설비용이 큰 사업으로 인식되기도 하며, 최근 관련 안전·방재 및 설계 요소 관련 법령과 지침이 지속적으로 제·개정됨에 따라 사업 비 변동요인이 증가하고 있다. 따라서 향후 증가할 지하도로 민간투자사업 추진시에 발생하는 다양한 위험요인에 대한 관리방안 마련 이 필요한 시점이다. 이에 본 연구는 지하고속도로 민간투자사업의 특수성을 반영한 기본계획 단계의 기술부문 평가지표에 대한 배점 개선안을 제시하는 것을 목적으로 한다. 이를 위해 현재 제3자 제안 공고상 기술 부문의 평가 배점을 검토하고, 신규 평가항목이 포함 된 후보 평가지표를 제시하였다. 또한 분석적 계층화 기법(AHP) 기반의 전문가 설문조사를 수행하여 평가지표의 우선순위를 도출해 최종적인 지하 고속도로 평가지표의 배점을 도출하였다. 평가항목별 배점 결과 건설계획 분야에는 ‘공사비, 보상비 등 사업비 선정(10 점)’, ‘장대터널계획 종합(25점)’, ‘시·종점부 도로접속 및 교통운영(18점)’ 평가항목이 추가되었다. 사업관리 및 운영계획 분야에는 ‘안 정적 운영을 위한 계획수립(76점)’, ‘운영계획의 창의성(24점)’, ‘재해 및 재난관리계획(21점)’ 등의 순으로 배점이 수정되었으며, 특히 시설 및 장비확보 계획, 유지보수 계획, 교통 및 영업관리 계획 등이 고려되는 ‘안정적 운영을 위한 계획수립’ 평가항목의 배점이 크게 증가하였다. 본 연구에서 제시한 배점 개선안을 통해 기본설계 단계에서부터 지하 고속도로 민간투자사업의 위험요인과 특수성을 고 려하여 사업을 추진할 수 있을 것으로 판단된다.

In this paper, we covered the basic design process of water-cooled cabinets and studied how to determine the target performance of heat exchanger design, which is essential in water-cooled cabinet design. A theoretical method was presented to set the target efficiency of the heat exchanger, and the pressure drop of air passing through the heat exchanger was predicted analytically. A cabinet-level thermal analysis was performed using the target efficiency and pressure drop data of the heat exchanger. The accuracy of the theoretical method was judged by comparing the theoretically predicted operating environment of the internal equipment with the analytically predicted operating environment of the internal equipment.

As the complexity and uncertainty of international construction projects increase, the importance of risk management capabilities in the construction industry has become more pronounced. Accordingly, Enterprise Risk Management (ERM) has become a widely adopted approach among organizations as a new way for more effective risk management. Despite its growing application, research related to ERM is still in its infancy, and most of the existing studies have been limited to financial industries. Therefore, this study aims to empirically examine the influence of ERM’s core elements on project risk management (PRM) and project performance within construction firms. Our findings indicate that the key ERM components—organization, policy, and culture—significantly enhance PRM processes, underscoring their critical role and importance. Additionally, effective PRM positively affects project outcomes, highlighting its significance for construction companies engaged in international projects. While ERM does not directly impact project performance, it indirectly improves outcomes through enhanced PRM capabilities. It suggests that ERM will contribute to the firm’s performance by improving the firm’s PRM capability through policies and a risk-focused culture corresponding to the adopted ERM organization and system..

A computational analysis was performed to study the thermal characteristics within the injection molding process of polygon mirrors in LiDAR systems. Such polygon mirrors are significantly influenced by the geometric shape of the injection mold as well as temperature and operating conditions. The analysis included the temperature distribution, heat flux, and variations in heat transfer rate of the polygon mirror from initial conditions. From the beginning of the injection process, temperature of the polygon mirror changes rapidly, leading to conductive heat transfer to the mold. There are large variations in the mirror temperature change depending on local position, and surface heat flux are affected by internal cooling path. These results are expected to be used as thermal design data for various polygon mirror processes.

현상학 연구는 질적 연구방법 중에서도 현상의 이면을 밝혀 그 본질을 도출하는 방법론이다. 이런 본래 의 현상학적 연구의 취지를 살려 연구의 성격에 맞춰 현상의 본질을 드러낼 수 있는 다양한 현상학적 방법 론이 적용될 필요가 있다. 하지만 현상학적 방법론은 현실적으로 지오르지(Giorgi)와 반마넨(Van Manen) 의 방법론에 치우쳐 있는 실정이다. 이런 문제의식을 바탕으로 본 연구자는 청소년의 학교폭력 경험에 적용 한 현상학적 자기평가방법의 분석방법을 고찰했다. 이 방법론은 환원과정이 4단계로 구체적이어서 현상학 의 본래 취지인 본질에 도달하는데 적합하다고 생각한다. 구체적으로 학교폭력 피해학생의 심층인터뷰를 활용해 현상학적 자기평가방법의 환원과정을 이 연구에서 보여주었다. 이 현상학적 자기평가방법은 사회복 지학이나 사회학에서 다루는 현상의 본질을 파악하기에 적합한 연구방법이라 할 수 있다.

In this study, we report the microstructural evolution and shear strength of an Sn-Sb alloy, used for die attach process as a solder layer of backside metal (BSM). The Sb content in the binary system was less than 1 at%. A chip with the Sn-Sb BSM was attached to a Ag plated Cu lead frame. The microstructure evolution was investigated after die bonding at 330 °C, die bonding and isothermal heat treatment at 330 °C for 5 min and wire bonding at 260 °C, respectively. At the interface between the chip and lead frame, Ni3Sn4 and Ag3Sn intermetallic compounds (IMCs) layers and pure Sn regions were confirmed after die bonding. When the isothermal heat treatment is conducted, pure Sn regions disappear at the interface because the Sn is consumed to form Ni3Sn4 and Ag3Sn IMCs. After the wire bonding process, the interface is composed of Ni3Sn4, Ag3Sn and (Ag,Cu)3Sn IMCs. The Sn-Sb BSM had a high maximum shear strength of 78.2 MPa, which is higher than the required specification of 6.2 MPa. In addition, it showed good wetting flow.

본 논문은 2019년부터 2023년 사이에 있었던 칠레 헌법제정 과정을 국민참여의 관점에서 분석하였다. 칠레 사회는 2019년 사회적 대폭발을 계기로 헌법을 새로 쓰는 데 합의하였다. 헌법상 기본권 보장을 목표로 헌법제정을 시도하였으나, 두 번의 시도 모두 부결되었다. 남녀동수 제헌 의회 구성, 원주민 대표성 강화, 시민참여 메커니즘 제도화 등 헌법제정 의 절차적 민주성이 높았다. 그러나 정당을 배제한 제헌의회를 구성함으 로써 제헌의원의 전문성이 떨어지고 국민들과의 목표가 불일치하여 국민 들의 요구를 헌법안에 담아내지 못했다는 비판을 받았다. 정당대표성과 제정기관의 전문성을 강화하여 2차 시도를 하였으나 헌법에 인간존엄성 을 담아내지 못했다. 헌법안 작성 기간이 너무 짧았고, 국민의 보편적 요 구와 거리가 먼 보수정당의 가치가 지나치게 반영되었기 때문이다. 또한 짧은 작성 기간과 헌법안 채택 방식은 숙의·심의보다는 속도있는 표결을 강조했다. 그러므로 모든 중요한 정치권력들이 헌법제정 과정에 균형있 게 참여하여 숙의·심의할 수 있는 제도적 보완 방안을 모색해야 할 것이 다.

Smart factory companies are installing various sensors in production facilities and collecting field data. However, there are relatively few companies that actively utilize collected data, academic research using field data is actively underway. This study seeks to develop a model that detects anomalies in the process by analyzing spindle power data from a company that processes shafts used in automobile throttle valves. Since the data collected during machining processing is time series data, the model was developed through unsupervised learning by applying the Holt Winters technique and various deep learning algorithms such as RNN, LSTM, GRU, BiRNN, BiLSTM, and BiGRU. To evaluate each model, the difference between predicted and actual values was compared using MSE and RMSE. The BiLSTM model showed the optimal results based on RMSE. In order to diagnose abnormalities in the developed model, the critical point was set using statistical techniques in consultation with experts in the field and verified. By collecting and preprocessing real-world data and developing a model, this study serves as a case study of utilizing time-series data in small and medium-sized enterprises.

PURPOSES : In this study, the resources and energy consumed to produce hot mix asphalt mixtures and hot mix reclaimed asphalt mixtures in asphalt concrete plants were estimated and the emissions from the detailed processes of the production process were evaluated based on TRACI(the tool for the reduction and assessment of chemical and other environmental impacts). METHODS : To estimate the energy consumption of the aggregate drying process, which consumes a significant amount of energy in the production process, an energy consumption calculation model based on the thermal equilibrium equation was used, and the energy consumed for material transportation, storage, and operation of other facilities was cited from the literature. RESULTS : For the system boundary conditions established and the inventory considered, the emissions to produce one ton of hot mix reclaimed asphalt mix are greater than the emissions to produce one ton of hot mix asphalt mix for a number of key impact categories. The process of producing hot mix reclaimed asphalt mixtures was evaluated to consume more resources and energy in the production of recycled aggregates and heating for drying than in the production of hot mix asphalt mixtures, but less resources and energy in the production of binders and natural virgin aggregates and the heating to heat these materials. CONCLUSIONS : The results of the emissions assessment using the life cycle inventory for the production of hot mix asphalt mixtures were generally similar to the results understood in the field and in much of the literatures, confirming the reliability of the methodology. However, in order to evaluate the dominance of specific processes or mixtures, it is believed that the construction of a wide range of inventory databases after inventory redesign is necessary for a specific and rigorous assessment.

유엔레바논평화유지군 예하의 해상임무단은 유엔의 평화유지임무 중 최초이 자 유일하게 해양에서 활동 중인 조직이다. 이 연구는 해상임무단이 수행 중인 위임명령에 근거를 제공하는 유엔 안전보장이사회 결의(이하 ‘안보리 결의’)들 을 종합적으로 분석하였다. 분석의 시간적 범위는 해상임무단이 임무를 시작한 2006년부터 2023년 현재까지이다. 특히, 이 연구는 해상임무단이 유엔의 군사계 획수립절차를 통하여, 개념적인 성격의 안보리 결의를 구체적인 군사작전으로 전환한 다음, 해양에서 이를 실제로 이행한 과정에 대하여 중점적으로 분석하 였다. 이와 같은 분석을 통하여 이 연구는 해상임무단의 활동이 2단계로 구분되는 것을 확인하였다. 2006년부터 2017년까지의 1단계에서는 해양작전의 체계를 확립하는 데 중점을 두었다면, 2018부터 2023년까지의 2단계에서는 레바논 해군 의 역량 강화가 해상임무단 활동의 주된 목표이다. 이와 같은 단계의 구분을 통하여 현재 해상임무단이 중점적으로 추진 중인, 임무단이 운용하는 함정의 척수를 줄이는 것은 2단계의 목표 즉, 레바논 해군의 능력을 강화하는 것과 연 결된 것임을 확인하였다. 그리고 이는 유엔레바논평화유지군의 전체적인 역량 이 감소되는 것으로 해석되어서는 안 된다는 논리에 타당한 근거를 제공한다. 한편, 해상임무단의 활동은 향후 해양에서 평화유지활동을 수행하게 될 조직 들에게 선행 사례로 제시될 수 있다. 특히, 이 연구에서 강조한 평화유지활동을 기획하는 과정에서 안보리 결의를 명확하게 분석하여 적용해야 한다는 점은 미 래 해양에서 실시하게 될 평화유지활동에 교훈을 제공한다.

The treatment process for Spent Filter(SF) of Kori-1 was developed that includes the following : 1) Taking out by robot system 2) Screening by ISOCS 3) Collection of representative samples using a sampling machine 4) Compression 5) Immobilization 6) Packaging and nuclide analysis and 7) Delivery/disposal. Although the robot system, ISOCS, sampling machine and immobilization facility are essentially required for building the above processing but decision to build the compression system and nuclide analysis system must be made after reviewing the need and cost benefit for their construction. In addition, for effcient SF treatment, it is necessary to determine the nuclide concentration range of the SF to which immobilization will be applied. In this study, a cost benefit analysis was performed on existing and alternative methods for processes related to compression treatment, nuclide analysis and immobilization methods, which are greatly affected by economics and efficiency according to the design. First, although the disposal cost is reduced with reducing the number of packaging drums by compressed and packaged but the expected benefits not be equal to or greater than the cost invested in building a compression system. As a result, non-compressed treatment of SF is expected to be economical because the construction cost of compression system is more expensive than the benefits of reducing disposal costs by compression. Second, a cost benefit analysis of direct and indirect nuclide analysis methods was performed. For indirect analysis, scaling factors should be developed and the drum scanner suitable for the analysis for DAW should be improved. As a result, direct analysis applied grouping options is expected to be more economical than indirect analysis requiring the cost for developing scaling factors and improving the scanner. Third, it is timeconsuming and inefficient to distinguish and collect filters that are subject to be immobilized according to the waste acceptance criteria among the disorderly stored SFs in the filter rooms. If the benefits of immobilization of the SFs selectively are not greater than the benefits of immobilization of all SFs, it can be economical to immobilize all SFs regardless of the nuclide concentration of them. As a result, it is more economical to immobilize all SFs with various nuclide concentrations than to selectively immobilize them. The conclusion of this study is that it is not only cost-effective but also disposal-effective to design the treatment process of SF to adopt non-compressed processing, direct analysis and immobilization of all SFs.

Dry active wastes (DAWs) are combustible waste generated during the operation and decommissioning of nuclear facilities, and are known to be generated in the amount of approximately 10,000 to 40,000 drums (based on 200 L) per unit. It consists of various types of protective clothing, paper, and plastic bags, and is stored in radioactive waste storage facilities. Therefore, reducing the volume of DAWs is an important issue in order to reduce storage costs and utilize the limited space of waste storage facilities. Heat treatment such as incineration can dramatically reduce the volume of waste, but as the waste is thermally decomposed, CO2, a global warming gas, is generated and there is a risk of emissions of harmful gases including radionuclides. Therefore, a heat treatment process that minimizes the generation of CO2 and harmful gases is necessary. One of the alternatives to incineration is to carbonize DAWs, dispose of carbonized materials below the release standard as non-radioactive waste, and selectively separate and stabilize inorganic components, including radionuclides, from carbonized DAWs. In this study, 13 types of DAWs generated from nuclear power plants were selected and their thermal decomposition characteristics were investigated to design a heat treatment process that replaces incineration. As a result of TGA analysis, the temperature at which thermal decomposition of each waste begins is 260-300°C for cotton, 320-330°C for paper, 315-420°C for synthetic fiber, 350°C for latex gloves. The mass of most samples decreased to less than 1 % of the initial weight after heat treatment, and dust suit and latex gloves had residues of 13.83% and 13.71% of the initial mass, respectively. The metal components of the residue produced after heat treatment of the sample were analyzed by EDS. According to the EDS results, cotton contains Ca and Al, paper contains Ca, Al and Si, synthetic fiber contains Ca, Cu and Ti, latex gloves contain Ca and Mg. Additionally, ICP analysis was performed to quantify the inorganic components. These results are expected to be applicable to the processing of DAW generated at nuclear facilities in the future.

Nuclear power generation is expected to be enlarged for domestic electricity supply based on the 10th Basic Plan of Long-Term Electricity Supply and Demand. However, the issues on the disposal of spent nuclear fuel or high-level radioactive waste has not been solved. KBS-3 concept of the deep geological disposal and pyroprocessing has been investigated as options for disposal and treatment way of spent nuclear fuel. In other way, the radionuclide management process with 6 scenarios are devised combining chlorination treatment and alternative disposal methods for the efficient disposal of spent nuclear fuel. Various scenarios will be considered and comprehensively optimized by evaluation on many aspects, such as waste quantity, radiotoxicity, economy and so on. Level 0 to 4 were identified with the specialized nuclide groups: Level 0 (NFBC, Hull), Level 1 (Long-lived, volatile nuclides), Level 2 (High heat emitting nuclides), Level 3 (TRU/RE), Level 4 (U). The 6 options (Op.1 to 6) were proposed with the differences between scenarios, for examples, phase types of wastes, the isolated nuclide groups, chlorination process sequences. Op.1 adopts Level 0 and 1 to separate I, Tc, Se, C, Cs nuclides which are major concerns for long-term disposal through heat treatment. The rest of spent nuclear fuel will be disposed as oxide form itself. Op.2 contains Sr separation process using chlorination by MgCl2 and precipitation by K2CO3to alleviate the burden of heat after heat treatment process. U/TRU/RE will be remained and disposed in oxide form. Op.3 is set to pyroprocessing as reference method, but residual TRU/RE chlroides after electrorefining will be recovered as precipitates by K3PO4. Op.4 introduces NH4Cl to chlorinate TRU/RE from oxides after Op.2 applied and precipitates them. TRU/RE/Sr will be simultaneously chlorinated by NH4Cl without MgCl2 in Op.5. Then, chlorinated Sr and TRU/RE groups will be separated by post-chlorination process for disposal. But, chlorinated Sr and TRU/RE are designed not to be divided in disposal steps in Op.6. In this study, the mass flow analysis of radionuclide management process scenarios with updated process variables are performed. The amount and composition of wastes by types will be addressed in detail.

The process basket assembly is an important module in pyroprocess, because pyroprocess is a batch process, so process materials are contained in a basket assembly and transferred with the basket. The basket assembly is composed of upper and lower assembly. The lower assembly is a basket or crucible which contains process materials, and it can have electrodes. The upper assembly mainly consists of heat shields, a flange, and connectors for supplying currents to electrodes of the lower assembly. During the electrolytic recovery process, the lower part is submerged into molten salt, whose temperature is about 500°C at least and the heat from salt is transferred to the upper assembly. And the heat affects the performance or durability of parts on the top of equipment and can raise cell temperature, which is an undesired situation. In addition, the handling equipment can pick the assembly when it is hottest, and during the transfer, the gripped part is under thermal and mechanical stresses. Because of this, the thermal effects from the heat should be required during equipment design stage. In this study, the thermal analyses of process basket assembly were conducted for 3 cases: the steady state of the basket assembly when it submerged in molten salt, the thermal and mechanical stresses when gripped by remote handling device, and the temperature changes under natural convection. These analyses were performed using Solidworks with flow simulation package, and the results will apply to improve the thermal resistant performance of the basket assembly.

It is essential to select materials with excellent mechanical properties to prevent chemical and mechanical damage to the surfaces of materials used in machines and structures and to extend their lifespan. Co-based stellite alloy, which has wear resistance, heat resistance, and corrosion resistance, is essential for products used in harsh environments. However, due to the problem of enormous costs, research on hard facing, which uses a stellite coating layer only on the contact surface, is urgently required. Currently, high-facing research on Stellite coating layers is focused on powder, and GMAW research using wire is relatively lacking. In this study, welding experiments were performed to form stable weld beads using stellite 6 welding wire, and the correlation between parameters and weld beads was analyzed. A CMT welder was used to minimize the heat effect on the base material.

Molybdenum-tungsten (Mo-W) alloy sputtering targets are widely utilized in fields like electronics, nanotechnology, sensors, and as gate electrodes for TFT-LCDs, owing to their superior properties such as hightemperature stability, low thermal expansion coefficient, electrical conductivity, and corrosion resistance. To achieve optimal performance in application, these targets’ purity, relative density, and grain size of these targets must be carefully controlled. We utilized nanopowders, prepared via the Pechini method, to obtain uniform and fine powders, then carried out spark plasma sintering (SPS) to densify these powders. Our studies revealed that the sintered compacts made from these nanopowders exhibited outstanding features, such as a high relative density of more than 99%, consistent grain size of 3.43 μm, and shape, absence of preferred orientation.

In order to solve the rapidly increasing domestic delivery volume and various problems in the recent metropolitan area, domestic researchers are conducting research on the development of “Urban Logistics System Using Underground Space” using existing urban railway facilities in the city. Safety analysis and scenario analysis should be performed for the safe system design of the new concept logistics system, but the scenario analysis techniques performed in previous studies so far do not have standards and are defined differently depending on the domain, subject, or purpose. In addition, it is necessary to improve the difficulty of clearly defining the control structure and the omission of UCA in the existing STPA safety analysis. In this study, an improved scenario table is proposed for the AGV horizontal transport device, which is a key equipment of an urban logistics system using underground space, and a process model is proposed by linking systematic STPA safety analysis and scenario analysis, and UCA and Control Structure Guidelines are provided to create a safety analysis.

Metal additive manufacturing (AM) has transformed conventional manufacturing processes by offering unprecedented opportunities for design innovation, reduced lead times, and cost-effective production. Aluminum alloy, a material used in metal 3D printing, is a representative lightweight structural material known for its high specific strength and corrosion resistance. Consequently, there is an increasing demand for 3D printed aluminum alloy components across industries, including aerospace, transportation, and consumer goods. To meet this demand, research on alloys and process conditions that satisfy the specific requirement of each industry is necessary. However, 3D printing processes exhibit different behaviors of alloy elements owing to rapid thermal dynamics, making it challenging to predict the microstructure and properties. In this study, we gathered published data on the relationship between alloy composition, processing conditions, and properties. Furthermore, we conducted a sensitivity analysis on the effects of the process variables on the density and hardness of aluminum alloys used in additive manufacturing.