In contemporary global warfare, the significance and imperative of air transportation have been steadily growing. Nevertheless, the Korean Air Force currently operates only with small and medium-sized military cargo planes, lacking larger aircraft. Consequently, the efficiency of their operations is constrained by the limited air transport capacity and the aging of their existing fleet, among other factors. Therefore, we have to consider to make future air transportation capability. Although the 2nd large-sized cargo-plane acquisition project is ongoing, its quantity is very small. In this study, we propose an optimal prediction model that takes into account practical constraints such as parking space availability, pilot availability, wartime daily maximum loads, while simultaneously maximizing both the effectiveness and efficiency of transport capacity for future warfare envirionment.

Amphibious operations represent a pivotal military maneuver involving the transfer of landing forces via ships, boats, and aircraft from sea to land. The success of such operations can be the decisive factor in the outcome of a war. Nevertheless, planning an amphibious assault is an intricate and formidable task, demanding careful consideration of numerous variables. This complexity is particularly evident in the formulation of loading plans for troops and equipment onto naval vessels. Historical accounts underscore the profound repercussions of errors in planning and loading on the execution of these operations. In pursuit of efficient loading procedures characterized by precision and time-effectiveness, our study has delved into the realm of optimization modeling. Employing a mixed-integer mathematical programming approach, this optimization model offers a valuable tool to streamline and enhance the preparatory phase of amphibious operations.

The automotive industry continuously strives to enhance safety for both drivers and passengers through technological advancements. Car side impacts have the potential to significant risks to passengers, So the automotive industry has proposed various technological solutions. As part of these efforts, the development of side impact beams, which are affixed to the inner frame of vehicle side doors to absorb and dissipate collision energy, has been a safety enhancement. Conventional side impact beams are manufactured using hot-rolled steel sheets and have a pipe-like configuration. However, these impact beams are fixed to the vehicle's chassis, which directly transfers the energy generated during a collision to the chassis frame. This paper aims to address this issue by proposing the development and optimization of vehicle door impact beams using a dual-beam structure and fastening method, utilizing shear bolts. Moreover, the focus is on optimizing the cross-sectional shape of the dual-beam impact structure. The evaluation criterion for optimization is based on the second moment of area of the cross-section. To validate these improvements, Static experiments were conducted, comparing the proposed dual-beam structure with the traditional impact beam. This research is expected to serve as a guideline for enhancing vehicle safety through design directions and validation methods.

Out-of-roundness is crucial for the proper functioning of individual products or parts in a machine. Mechanical components often consist of circular elements that require precise alignment. These circular parts are used in critical areas of the machine, and the shape characteristics of each component can significantly impact overall performance. In this study, we focus on a specific specimen and use three different methods - the Diameter method, Radius method, and Three-point method - to measure its out-of-roundness. The collected data is then analyzed using one-way ANOVA to propose an effective out-of-roundness measurement technique suitable for industrial settings.

Injection molding is a process of shaping resin materials by heating them to a temperature above their melting point and then using a mold. The resin material is injected into and cooled within the mold cavity, solidifying into the desired shape. The core and cavity components that make up the mold cavity are crucial elements for the precision molding in injection molding. In the case of precision mold production, the application of 5-axis machining technology is required to ensure high machining quality for complex shapes, and among these factors, the tool angle is a critical machining condition that determines the surface roughness of the workpiece. In this study, we aim to measure the surface roughness of the machined surface of KP4A specimens during machining processes with variations in the tool angle and analyze the correlation between the tool angle and surface roughness.

This paper proposes a standardized vehicle body repair manual for vehicles with major damage to the rear side members caused by rear-end collisions. The manual is used to refine the vehicles. Typical work involves replacing large traffic accident modes with new members or modifying and aligning existing members. If repairs are made for various reasons, the members should be attached based on the body of a new vehicle. Unlike new vehicle members, the accident vehicle repair process depends heavily on the operator's skilled skills (i.e., the performance, purpose, level, and quality of the body replacement work due to the nature of the vehicle body replacement work). When repairing or replacing a rear side member of a body repair, three methods of operation are applied because the damage and deformation vary depending on the object of the other party, although the degree of damage varies. There is no standardized manual for side member over-hole replacement, partial replacement, or partial modification, since these repair methods vary depending on the operator's thoughts and angle of view. Therefore, customers should use standardized vehicle repair manuals to ensure that their vehicle receives the same repair when damaged. This study is expected to develop a standardized vehicle repair manual to reduce the drop in used market prices after replacement or repair of rear side members at vehicle repair plants.

ars using diesel have always had problems with reducing exhaust fumes, and have been studied steadily in this regard. There were studies on the remanufacturing effect of DOC catalyst deactivated by diesel vehicle smoke reduction device, analysis of vehicle fire accident cases caused by damage to diesel vehicle smoke reduction device, and related studies on the remanufacturing effect of diesel vehicle smoke reduction device DPF. This study also developed an optimized system for complete combustion of smoke generated by institutions using diesel engines in low-temperature exhaust gases. The main systems to be developed are high-performance heaters, burner structures that can maintain ignition in exhaust flows, and exhaust flow control units that reduce exhaust gas backflow effects caused by diesel engines.

해양산업시설에서는 많은 종류의 유해물질의 배출 가능성이 존재하기 때문에 이에 대한 체계적인 대응체계가 필요하다. 그 중 연속자동 측정이 가능하면서 ppb 수준의 낮은 검출하한 (limit of detection:LOD)를 갖는 센서 구현은 매우 중요하다. 이를 위해 본 연구에서 는 활성탄소(carbon black)와 Indium tin oxide (ITO) 나노입자를 혼합한 film의 표면저항의 변화를 이용한 고성능 센서 제안 및 구현을 위해 성능인자를 최적화하였다. 센서 구조는 접촉 면적과 전극 간격을 최적화하였다. 접촉 면적이 증가하면 감도, LOD 성능이 향상되었으며 60 mm2에서 최적화되었다. 또한, 전극 간격은 접촉 면적을 일정하게 유지한 상태에서 변화시켰으며 센서 응답은 전극 간격이 감소함에 따라 증가하는 것을 확인하였다. 마지막으로 센서 표면에서의 유해물질의 잔류시간 증가를 위해 화학흡착제를 적용하였다. 화학흡착제는 유해 물질을 선택적으로 흡수할 수 있는 polyester계를 선택하였다. 그 결과 농도가 증가함에 따라 응답이 선형적으로 증가하여 센서로 활용이 가능한 것을 확인하였다. 이러한 3가지의 방법을 통해 센서를 제작하였을 때 액상 유해물질을 기존 센서의 LOD(89.9 ppb)와 비교 10~40 ppb 정도의 낮은 농도를 검출할 수 있는 센서를 구현하였다.

프로바이오틱스 제품에 대한 수요가 지속적으로 증가하 고 있으며, Lactobacillus 균주가 가장 대중적인 프로바이 오틱스로 널리 사용되고 있다. 프로바이오틱스는 기준에 적합한 균수의 확보가 중요하며 제조원가나 시간 등을 낮 추기 위해 배양법의 개발이 필요하므로 Lactobacillus 생 산을 위한 배양 조건이 최적화되었다. 반응표면방법론에 의한 통계적 최적화에서 반응 변수에 영향을 미치는 독립 변수의 최적 조건은 Lactobacillus acidophilus의 경우 22.55 시간(배양시간), 25oC(배양온도), 3.41%(프리바이오틱스 농 도); Lactiplantibacillus plantarum의 경우 24시간, 30.86oC, 2.00%; Lacticaseibacillus rhamnosus의 경우 66.67시간, 35oC, 3.41%이었다. Lactobacillus의 최적 배양조건은 예측 한 결과와 실제 결과가 밀접하게 일치하는 것을 확인하였 다. 이러한 데이터는 수율 높은 Lactobacillus를 생산하는 데 중요한 포인트를 제공할 것이다.

PURPOSES : A model for minimizing cutting loss and determining the optimum layout of blocks in pavements was developed in this study. METHODS : Based on literature review, a model which included constraints such as the amount, volume, overlap, and pattern, was developed to minimize the cutting loss in an irregular pavement shape. The Stach bond, stretcher bond, and herringbone patterns were used in this model. The harmony search and particle swarm algorithms were then used to solve this model. RESULTS : Based on the results of the model and algorithms, the harmony search algorithm yielded better results because of its fast computation time. Moreover, compared to the sample pavement area, it reduced the cutting loss by 20.91%. CONCLUSIONS : The model and algorithms successfully optimized the layout of the pavement and they have potential applications in industries, such as tiling, panels, and textiles.