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Supply chain management is used in both the private and public sectors to meet the needs of consumers while maximizing the economic profitability of an organization. However, in the public sector, military logistics focuses on combat readiness, unlike the private sector, which seeks to maximize profits. Therefore, it is necessary to maintain an appropriate supply level to keep state-of-the-art combat weapon systems operational. Spare parts comprise a large proportion of the equipment maintenance costs. Therefore, several companies have consistently attempted to strike a balance between the cost and supply of spare parts by improving the demand forecasting accuracy. Because the demand for spare parts fluctuates based on equipment requirements, accurate demand forecasting is critical. Fortunately, the recent accumulation of maintenance data has led to more opportunities to improve the demand forecasting accuracy.

Controlling the morphology and surface properties of gold nanocrystals (AuNCs) can facilitate tailoring their localized surface plasmon resonance (LSPR) and surface-enhanced Raman scattering (SERS) properties for biomedical applications. However, the shape-controlled synthesis of AuNCs for bioapplications remains challenging, given its critical issues, such as the use of toxic reagents and multiple complicated steps. This study demonstrates the facile, biocompatible, and shape-controllable synthesis of AuNCs. This method employs human α-elastin (HαE) self-assemblies as a shape-directing template, reducing agent, and surfactant. Since HαE is a ubiquitous protein present in human tissue, it is non-toxic and non-immunogenic. This method is thus simple and biocompatible. Of particular note, the sheet-type HαE template enables the shape-controlled synthesis of AuNCs—gold nanoparticles, nanosheets, and a rose-flower-like nanostructure (AuRF) stacked with multiple nanosheets. Among the AuNCs, the AuRF exhibits unique optical and electromagnetic properties—an LSPR peak in the near-infrared (NIR) region and characteristic SERS peaks—given the rough surface with sharp edges. To the best of our knowledge, this is the first report on the biosynthesis of AuNCs using human-derived biomolecules such as HαE. The shape-controllable biosynthesis of AuNCs based on HαE may open up possibilities for a wide range of biomedical applications of AuNCs.

A new species of Lecithocera Herrich-Shaffer, L. atriptera Park, sp. nov., is described from Korea, and two species, Homaloxestis myeloxesta Meyrick, 1932 and Lecitholaxa indigens (Meyrick, 1914), are reported for the first time from Korea. Halolaguna sublaxata Gozmany is newly known from Isl. Jeju-do. In addition, new localities for the six previously known species are given. A tentative checklist of Lecithoceridae in Korea is provided, with their type depositories.

A new species of Zanclognatha Lederer, 1857 of the family Erebidae, Z. querciella sp.n., one species of Family Erebidea, Asota egens (Walker, 1854) and two species of Family Noctuidae: Meganephria retinea Gyulai and Ronkay, 1999 and Amphipyra subrigua Bremer and Grey, 1853, are reported for the first time from Korea. In addition, larval feeding habits with their host plants for three species are newly recognized from Korea. Illustration of adults, larvae for Zanclognatha querciella and Meganephria retinea, and the genitalia of male or female for all species are provided.

Liver fibrosis is an excessive wound healing process that occurs in response to liver damage depending on underlying aetiologies. Currently, there are no effective therapies and FDA-approved therapeutics for the treatment of liver fibrosis except liver transplantation. Multipotent adipose-derived stem cells (ADSCs) have received significant attention as regenerative medicine for liver fibrosis owing to their advantages over stem cells with other origins. However, intrinsic limitations of stem cell therapies, such as cellular rejection and tumor formation, have impeded clinical applications of the ADSC-based liver therapeutics. To overcome these problems, the extracellular nanovesicles (ENVs) responsible for the therapeutic effect of ADSCs (A-ENVs) have shown considerable promise as cell-free therapeutics for liver diseases. However, A-ENVs have not been used for the treatment of intractable chronic liver diseases including liver fibrosis and cirrhosis. Therefore, in this study, we investigated the in vitro and in vivo antifibrotic efficacy of A-ENVs in thioacetamide-induced liver fibrosis models. A-ENVs significantly downregulated the expression of fibrogenic markers, such as matrix metalloproteinase-2, collagen-1, and alpha-smooth muscle actin. The systemic administration of A-ENVs led to high accumulation in fibrotic liver tissue and the restoration of liver functionality in liver fibrosis models through a marked reduction in α-SMA and collagen deposition. These results demonstrate the significant potential of A-ENVs for use as extracellular nanovesicles-based therapeutics in the treatment of liver fibrosis and possibly other intractable chronic liver diseases.

We are developing a next generation distribution intelligence system to cope with changes in the distribution system environment. In order to utilize it in the real system, it is necessary to enhance functions such as linkage of existing distribution equipment with increased distributed power supply, application of distribution system of new equipment such as IoT, and big data processing in connection with various systems. Flexibility, compatibility, and security. This paper introduces the concept of next generation distribution intelligence system that can be extended to various systems to be appeared in the future and can be used both at home and abroad by using standard protocol and open source

A semi-submersible structure has been widely used for offshore drilling and production of oil and gas. The small water plane area makes the structure very sensitive to weight increase in terms of payload and stability. Therefore, it is necessary to lighten the substructure from the early design stage. This study aims at an optimization of hull structure based on a sophisticated yield and buckling strength in accordance with classification rules. An in-house strength assessment system is developed to automate the procedure such as a generation of buckling panels, a collection of required panel information, automatic buckling and yield check and so on. The developed system enables an automatic yield and buckling strength check of all panels composing the hull structure at each iteration of the optimization. Design variables are plate thickness and stiffener section profiles. In order to overcome the difficulty of large number of design variables and the computational burden of FE analysis, various methods are proposed. The steepest descent method is selected as the optimization algorithm for an efficient search. For a reduction of the number of design variables and a direct application to practical design, the stiffener section variable is determined by selecting one from a pre-defined standard library. Plate thickness is also discretized at 0.5t interval. The number of FE analysis is reduced by using equations to analytically estimating the stress changes in gradient calculation and line search steps. As an endeavor to robust optimization, the number of design variables to be simultaneously optimized is divided by grouping the scantling variables by the plane. A sequential optimization is performed group by group. As a verification example, a central column of a semi-submersible structure is optimized and compared with a conventional optimization of all design variables at once. Keywords: Semi-submersible structure, Steepest descent method, Weight optimization, Buckling strength, Yield strength

Three genera Megacraspedus Zeller, 1839, Aulidiotis Meyrick, 1925, and Cuprina Sinev, 1988 and four species of the superfamily Gelechioidea are reported for the first time from the Korean Peninsula. They are Megacraspedus coleophorodes (Li and Zheng, 1995) and Aulidiotis phoxopterella (Snellen, 1903) of Gelechiidae; Martyringa ussuriella Lvovsky, 1979 of Oecophoridae; and Cuprina fuscella Sinev, 1988 of Stathmopodidae. Images of adults and genitalia of the species are given. Keywords: Lepidoptera, Aulidiotis, Cuprina, Megacraspedus, New record

Human adipose-derived stem cells (hADSCs) formed robust cell sheets by engineering the cells with soluble cell adhesive molecules (CAMs), which enabled unique approaches to harvest large area hADSC sheets. As a soluble CAM, fibronectin (FN) (100 pg/ml) enhanced the cell proliferation rate and control both cell-to-cell and cell-to-substrate interactions. Through this engineering of FN, a transferrable hADSC sheet was obtained as a free-stranding sheet (122.6 mm2) by a photothermal method. During the harvesting of hADSC sheets by the photothermal method, a collagen layer in-between cells and conductive polymer film (CP) was dissociated, to protect cells from direct exposure to a near infrared (NIR) source. The hADSC sheets were applied to chronic wound of genetically diabetic db/db mice in vivo, to accelerate 30% faster wound closure with a high closure effect (εwc) than that of control groups. These results indicated that the engineering of CAM and collagens allow hADSC sheet harvesting, which could be extended to engineer various stem cell sheets for efficient therapies.

We present a high-temperature proton exchange membrane fuel cell (HT-PEMFC) system model that accounts for fuel reforming, HT-PEMFC stack, and heat-recovery modules along with heat exchangers and balance of plant (BOP) components. In the model developed for analysis, the reaction kinetics for the fuel reforming processes are considered to accurately capture exhaust gas compositions and reactor temperatures under various operating conditions. The HT-PEMFC stack model is simplified from the three-dimensional HT-PEMFC CFD models developed in our previous studies. In addition, the parasitic power consumption and waste heat release from the various BOP components are calculated based on their heat-capacity curves. An experimental fuel reforming reactor for a 5.0 kWe HT-PEMFC system was tested to experimentally validate the fuel reforming sub model. The model predictions were found to be in good agreement with the experimental data in terms of exhaust gas compositions and bed temperatures. Additionally, the simulation revealed the impacts of the burner air-fuel ratio (AFR) and the steam reforming reactor steam-carbon ratio on the system performance and efficiency. In particular, the combined heat and power efficiency of the system increased up to 78% when the burner AFR was properly adjusted. This study clearly illustrates that an HT-PEMFC system requires a high degree of thermal integration and optimization of the system configuration and operating conditions.

Self-assembled nanoparticles based on PEGylated human α-elastin were prepared as a potential vehicle for sustained protein delivery. The α-elastin was extracted from human adipose tissue and modified with methoxypolyethyleneglycol (mPEG) to control particle size and enhance the colloidal stability. The PEGylated human α-elastin showed sol-to-particle transition with a lower critical solution temperature (LCST) of 25°C-40°C in aqueous media. The PEGylated human α-elastin nanoparticles (PhENPs) showed a narrow size distribution with an average diameter of 330±33nm and were able to encapsulate significant amounts of insulin and bovine serum albumin (BSA) upon simple mixing at low temperature in water and subsequent heating to physiological temperature. The release profiles of insulin and BSA showed sustained release for 72h. Overall, the thermo-responsive self-assembled PhENPs provide a useful tool for a range of protein delivery and tissue engineering applications.

Population and development are concentrated by urbanization. Consequently, the usage of underground area and the riverside area have been increased. By increasing impermeable layer, the urban basin drainage is depending on level of sewer. Flood damage is occurred by shortage of sewer capacity and poor interior drainage at river stage. Many of researches about flood stress the una vailability of connection at the river stage with the internal inundation organically. In this study, flood calculated considering rainfall and combined inland-river. Also, using urban runoff model analyze the overflow of sewer. By using results of SWMM model, using floo d inundation analysis model analyzed internal drainage efficiency of drainage system. Applying SWMM model, which results to flood inundation analysis model, analyzes internal drainage efficiency of drainage system under localized heavy rain in a basin of th e city. The results of SWMM model show the smoothness of internal drainage can be impossible to achieve because of the influence of the river level and sewer overflow appearing. The main manholes were selected as the manhole of a lot of overflow volume. Overflow reduction scenarios were selected for expansion of sewer conduit and instruction retention pond. Overflow volume reduces to 45% and 33~64% by retention pond instru ction and sewer conduit expansion. In addition, the results of simulating of flood inundation an alysis model show the flood occurrence by road runoff moving along the road slope. Flooded area reduces to 19.6%, 60.5% in sewer condu it expansion scenarios.Key words : Urban basin, Internal inundation, Flood damage, SWMM, Flood inundation analysis초 록도시화로 인한 인구집중 및 개발 집중현상으로 하천변 저지대 및 지하공간 사용이 증가하였고 , 불투수층이 증가하여 도시유역의 배수체계는 우수관거에 의존하고 있다. 이러한 변화로 인한 우수관거의 저류용량 부족 및 외수위의 영향으로 인한 도심지 역류 현상으로 인한 침수피해가 발생하고 있다. 하지만 기존의 홍수범람에 관한 연구는 대부분 외수범람과 내수침수를 유기적으로 연결하지 못하고 있다 . 본 연구에서는 상습침수가 발생하는 도시유역에 대하여 도시유역 유출특성을 고려한 홍수의 정확한 예측을 위해 강우분석 및 외수위를 고려하고, 도시유출모형인 SWMM 모형을 이용하여 하수관거의 월류를 분석하였고, 이 결과를 홍수범람해석 모형과 연계하여 도시유역에서의 집중호우 발생시 침수해석을 실시하여 수방시설물의 홍수배제 효율을 분석하였다. SWMM 모형의 적용결과 외수위영향에 따른 원활한 내수배제가 불가능 한 것으로 나타났고, 관거 월류량이 많아진 것으로 나타났다. 월류된 우수가 지면을 따라 흐를 경우 저지대의 침수가 예상되고, 월류량이 많은 맨홀을 주요맨홀로 선정하였고, 월류수 저감을 위한 방안으로 주요 맨홀의 인근 지역에 저류지를 설치하는 방안과 각 맨홀들을 연결하는 관거를 확대하는 방안을 설정하였다. 월류 저감 시나리오 적용 결과 저류지 설치시 월류량의 45%, 관거 확대시 33∼64%의 저감효과를 보였다. SWMM 모형의 결 Water Engineering

The flowfield characteristics of a square prism having a small triangular prism at the upstream side were investigated by visualizing the flow field using PIV. The ratio of the width of the triangular prism to that of the square prism and the gap ratios between the square and triangular prisms were selected as the experimental parameters. The results are summarized as follows. The Strouhal number measured on the wake side of the square prism, which had the same characteristics as the drag reduction rate, in- creased, and then decreased with the gap ratio for the same width ratio. For a square prism having a small triangular prism, the stagnation regions were represented at the upstream and downstream sides of the square prism. The size of the stagnation region in- creased with the width ratio at the upstream side of the square prism, and decreased at the downstream side.

The purpose of this study is to investigate the effect of the impinging plate on combustion process in Diesel engine. Especially, the variation of exhaust emission and engine performance by the change of fuel injection timing and fuel injection pressure between the trial engine with impinging plate and the prototype engine were examined. The nitrogen oxide concentration of the trial engine decreased more than 50% compared to the prototype engine, however, smoke concentration of the trial engine indicated higher degree than the prototype engine. The smoke concentration, fuel consumption rate and exhaust gas temperature decreased as the fuel injection timing become faster, whereas the nitrogen oxide concentration decreased as the fuel injection timing is retarded. The nitrogen oxide concentration, fuel consumption rate and exhaust gas temperature decreased as the fuel injection pressure become lower. But smoke concentration decreased as the fuel injection pressure become higher.

The local heating of poly(3,4-ethylenedioxythiophene) (PEDOT) by a photothermal effect directed by near-infrared (NIR) light induces unfolding of absorbed collagen triple helices, yielding soluble collagen single-helical structures. This dissociation of collagens allowed the harvesting of a living idiomorphic cell sheet, achieved upon irradiation with NIR light (λ=808 nm). The PEDOT layer was patterned and cells were successfully cultured on the patterned substrate. Cell sheets of various shapes mirroring the PEDOT pattern could be detached after a few minutes of irradiation with NIR light. The PEDOT patterns guided not only the entire shape of the cell sheets but also the spreading direction of the cells in the sheets. This photothermally induced dissociation of collagen provided a fast non-invasive harvesting method and tailor-made cell-sheet patterns.

The wear behavior of epoxy matrix composites filled with nano sized silica particles is discussed in this paper. Especially, the variation of the coefficient of friction and the specific wear rate under the various applied load and sliding velocity were investigated for these materials. Wear tests of pin-on-disc mode were carried out and followed by scanning electron microscope observations. The presence of silica filler in epoxy composites was demonstrated significant influence on the friction and wear behavior of epoxy nanocomposites. With the incorporation of silica filler into the epoxy matrix, reduction of the coefficient of friction and specific wear rate were identified. Wear mechanism was discussed by analyzing the worn surface by scanning electron microscope as well.

【The purpose of this paper is to investigate polarization characteristics of WC-based alloy coatings in alkaline solution. The coatings were fabricated with WC-CrC-Ni, WC-Co-Cr and WC-Co composite powders by HVOF process. Corrosion tests of coatings and substrate were carried out using potentiostat/galvanostat at solution with pH 8 and pH 13. Corrosion potential(Ecorr) and corrosion current density(Icorr) could be studied from polarization curve, and corrosion behavior was analyzed by SEM and EDS. WC-Co-Cr coating and WC-CrC-Ni coating showed more favorable anti-corrosion characteristics than WC-Co coating and substrate at solution with pH 8 and pH 13.】

Extracellular matrices (ECMs), isolated through decellularization of mammalian tissues, have been successfully used in a variety of tissue engineering and regenerative medicine applications. The composition and spatial structure of ECMs provide not only specific instructive cues for the growth, migration, and differentiation of various cells in vitro, but afford ideal substrates for in vivo tissue reconstruction. Adipose tissue, which is the most prevalent and expendable tissue in the body and can be harvested in large quantities with minimal morbidity, has received much attention as a rich source of ECMs. Recent studies have designed different processes to isolate intact ECMs from adipose tissue and have fabricated various three-dimensional (3-D) tissue engineering scaffolds such as microparticles, powders, sponges, sheets, and hydrogels for use in regenerative medicine, particularly for patients requiring soft tissue regeneration. Indeed, because of the abundance of ECM components within adipose tissue, combined with the relative ease of large tissue harvesting, adipose tissue is a valuable resource in tissue regeneration therapy, encompassing autotransplantation, allotransplantation, and xenotransplantion. We briefly review extraction and decellularization techniques of ECMs from adipose tissue, biological characterization and fabrication of ECM-based tissue engineering scaffolds, and their use in soft tissue engineering.

This study evaluated experimentally static strength for bogie frame of an urban maglev train including performing fatigue analysis, cumulative damage and fatigue test based on a developed fatigue load and as a final outcome, aimed to propose a fatigue strength evaluation method for the bogie frame of urban maglev. The results of FEM analysis adopting load combinations showed that all data was under a fatigue limit of the butt welded joint made of A6005 in Goodman diagram. The cumulative fatigue damage was calculated at the highest level from a bolt connecting area of electromagnetic pole in casting block but the total sum was evaluated as D = 0.808 based on 1 × 107 cycles, which indicates it did not exceed the failure criteria. In addition, as the results of fatigue test, there was no crack on the any position of the bogie frame with the outcomes that corresponded to the results of fatigue test.

The protection switching technology is widely adopted in the fiber-optical transmission equipments based on TDM(Time Division Multiplexing), such as PDH, SDH/SONET. A variety of protection switching algorithms for Ethernet networks and the progress of standardization are summarized in the document. There are several kinds of protection switching algorithms for Ethernet networks, such as STP, RSTP, MSTP and etc. However, since Ethernet signal move through detour route, it causes much time to recover. Accordingly, it is difficult to secure a usability of Ethernet networks and QOS(Quality of Service). Also, if the protection switching protocol standardized by IEEE and ITU-T is used, it remains a inherent network switching time for protection. Therefore, a specific protection switching algorithm for Ethernet are needed for seamless and stable operation of Ethernet networks service for Distribution Automation System(DAS). A reliable protection algorithm with no switching delay time is very important to implement Self-healing service for DAS. This study of FPGA based protection switching algorithm for Ethernet networks shows that in case of faults occurrence on distribution power network, immediate fault isolation and restoration are conducted through interaction with distribution equipments using P2P(Peer to Peer) communication for protection coordination. It is concluded that FPGA based protection switching algorithm for Ethernet networks available 0ms switching time is crucial technology to secure reliability of DAS.

When the shorelines were contaminated by oil, oiled shorelines were assessed systematically by SCAT and guideline of cleanup activities and shorelines treatment endpoints based on SCAT were established and operated in case of well developed countries like USA and Canada. However, shorelines cleanup assessment technique are not established clearly in our country. In this study, we studied on the shorelines cleanup assessment technique suitable for Korean shorelines feature. That is, composition of SCAT organization, classification of shorelines and division of oiled shorelines by segment that are elements of SCAT were studied, and we suggest the measures related to above elements suitable for shorelines feature of our country.

The human placenta, a complex organ, which facilitates exchange between the fetus and the mother, contains abundant extracellular matrix (ECM) components and well-preserved endogenous growth factors. In this study, we designed a new dermal substitute from human placentas for full-thickness wound healing. Highly porous, decellularized ECM sheets were fabricated from human placentas via homogenization, centrifugation, chemical and enzymatic treatments, molding, and freeze-drying. The physical structure and biological composition of human placenta-derived ECM sheets dramatically supported the regeneration of full-thickness wound in vivo. At the early stage, the ECM sheet efficiently absorbed wound exudates and tightly attached to the wound surface. Four weeks after implantation, the wound was completely closed, epidermic cells were well arranged and the bilayer structure of the epidermis and dermis was restored. Moreover, hair follicles and microvessels were newly formed in the ECM sheet-implanted wounds. Overall, the ECM sheet produced a dermal substitute with similar cellular organization to that of normal skin. These results suggest that human placenta-derived ECM sheets provide a microenvironment favorable to the growth and differentiation of cells, and positive modulate the healing of full-thickness wounds.

Recently, many problems related on shoreline response to spill oil were exposed again on a occasion of M/T Hebei spirit accident even though the weakness on the shoreline response system has been brought up since M/T Sea Prince oil spill accident. Therefore the establishment of shoreline response system that best suits our country is needed through considering the response system of well-developed country. The socioeconomic conflict between the persons concerned on the clean-up endpoints can be sharpened in Korea because the frequency of coastal use of our country is too high compared to other countries. Thus procedural justification, that is, how the clean-up endpoints be established is more important than what type of clean-up endpoints be used. In the present paper, we attempted to suggest a new manner on the decision making system for clean-up endpoints that best suits our country. The decision making system for clean-up endpoints need to be divided into two steps, that is, set-up step of clean-up endpoints criteria and decision step of clean-up endpoints. The decision making organization of local governments play a key role in case of set-up step of clean-up endpoints criteria, while the response command headquarters under Korean coast guard and decision making organization of local governments codecide whether the clean-up endpoints criteria is fits or not.