By developing molds and facilities to horizontally mold the functional part of the dry-cast concrete block, We intend to develop molds and a series of facilities to horizontally mold the functional part of the dry-cast concrete block to increase production per cycle while maintaining existing production methods and major facilities. In order to do so, CAE analysis is first required to develop molds and facilities for horizontally molding the functional part of the drycast concrete block in the horizontal direction. The procedure will be carried out by reviewing the validity of boundary conditions and physical properties, 3D modeling, grid generation, construction of analysis models, model validity, analysis according to frequency changes, and analysis according to physical properties. First, through the comparison of two-point support, three-point support, and two-point and three-point support in the constraint conditions, We would like to compare it with the actual molded product in the horizontal direction. But first of all, it is considered two-point support in the constraint conditions in this paper.

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.

한 척의 선박을 건조하기 위해서는 다양한 크기의 블록(block)들을 이동 및 탑재해야 한다. 이러한 과정에서 블록의 체결 방법 및 각 조선소 설비 특성에 맞는 다양한 기능에 부합하는 러그를 사용하고 있다. 블록 구조의 중량 및 형태에 따라서 러그의 크기와 형상이 다양하며, 샤클(shackle)이 체결되는 홀 주변에 부족한 강성을 보완하기 위하여 덧판(doubling pad)을 용접하여 구조를 보강한다. 리프팅 (lifting) 조건별 러그의 설계를 하는 방법은 보 이론(beam theory)에 의한 수계산 방법과 유한요소해석 모델링을 이용한 구조해석을 수행하고 있다. 해석적 방법의 경우, 요소의 종류와 모델링 방법에 따라서 결과 차이가 발생하여 표준화된 평가법의 정립이 필요한 상황이다. 이러한 모호한 방법론 적용 시 블록의 이동 및 반전(turn-over) 과정 중에서 심각한 안전 문제를 유발할 가능성이 있다. 본 연구에서는 러그의 실제 탑재공정에 따른 구조 응답을 평가할 수 있는 모델링 조건, 평가법을 확정하고자 다양한 변수의 영향을 수치 구조해석을 통하여 비교 및 분석하였다. 러그 홀(hole) 주변 덧판부와 용접 비드(bead)를 표현한 모델링 기법이 가장 실제적인 거동 결과를 주고 있다. 실제 러그와 동일 한 조건(용접부 비드만 주재료와 연결)의 모델링에 등가하중을 적용한 결과는 MPC 하중 적용 결과보다 낮은 최종강도를 나타낸다. 더불어 해석 시간 단축을 위해서 2차원 쉘(shell) 요소를 적용한 경우, 덧판 두께를 85% 수준으로 감소시켜서 안전사용하중을 예측할 수 있음을 확 인하였다. 논문에서 검토한 다양한 변수의 영향들 결과는 러그 설계 및 안전사용하중 예측에 근거 자료로 활용될 것으로 기대된다.

A deep geological repository for disposal of high-level radioactive waste (HLW) consists of the canister, buffer material, and natural rock. If radionuclides leak from a disposal container, it can pass through buffer materials and rock, and move into the biosphere. Transport and migration of radionuclides in the rock differently were affected by the fracture type, filling minerals in the fracture, and the chemical and hydraulic properties of the groundwater. In this study, aperture distribution in fractured granite block was investigated by hydraulic test and CFD analysis. The fractured rock block (1 m × 0.6 m × 0.6 m), which is simulated as natural barrier, was prepared from Iksan, Jeollabuk-do. 9 test holes were drilled and packer system was installed to perform hydraulic test at the surface of fracture. 3D model simulated for aperture distribution of rock block was made using results of hydraulic test. And then, CFD analysis was performed to evaluate the co-relation between experiment results and analysis results using FLUENT code.

In Laos, smallholder cattle farmers rely primarily on natural grassland grazing, which needs to be improved for fattening. Notably, most cattle prices are determined by the middleman, by looking, so buyers tend to undervalue their price, which makes cattle farming a minimal investment. Urea-Molasses Block (UMB) supplements can effectively enhance a nutrient diet in low-quality roughage systems. This study aimed to determine factors affecting UMB and farmers’ Willing To Pay (WTP) for UMB as a new input material with data from six villages, two districts of the Vientiane Capital, in January and July 2019. The results indicate that farmers with relatively high education, consent to the positive effect of UMB, and previous experience purchasing feed during the dry season are more likely to pay a high positive WTP. The average WTP for UMB ranges from USD 5.7 to 6.5 per month for one cattle, which is approximately 10.2~11.6% of current annual costs for average smallholder cattle farmers. These findings will be significant in improving productivity at the initial development stage of farms in Laos, especially for smallholder farmers.

In this study, a graphite block is fabricated using artificial graphite processing byproduct and phenolic resin as raw materials. Mechanical and electrical property changes are confirmed due to the preforming method. After fabricating preforms at 50, 100, and 150 MPa, CIP molding at 150 MPa is followed by heat treatment to prepare a graphite block. 150UP-CIP shows a 12.9% reduction in porosity compared with the 150 MPa preform. As the porosity is decreased, the bulk density, flexural strength, and shore hardness are increased by 14.9%, 102.4%, and 13.7%, respectively; and the deviation of density and electrical resistivity are decreased by 51.9% and 34.1%, respectively. Therefore, as the preforming pressure increases, the porosity decreases, and the electrical and mechanical properties improve.

재생에너지의 보급과 기후변화를 대응하기 위한 해결책으로 수소에너지에 대한 관심이 늘어나고 있다. 수소는 미 이용 전력을 대용량 장주기로 저장하기에 가장 적합한 수단이며 이러한 수소를 생산하는 기술 중 수전해는 물에 전기에너지 를 인가하여 수소를 생산하는 친환경적 수소생산 기술로 알려져 있다. 수전해의 구성 요소 중 분리막은 음극과 양극을 물리 적으로 분리할 뿐만 아니라 생성되는 수소와 산소의 섞임 현상을 방지하며 이온의 전달을 가능하게 하는 복합적인 역할을 수 행한다. 특히 기존의 수전해 기술들의 단점을 보완할 수 있는 차세대 음이온 교환막 수전해에서의 핵심은 우수한 음이온 교 환막을 확보하는 것이다. 높은 이온 전도성과 알칼리 환경에서 우수한 내구성을 동시에 가지려는 많은 연구들이 진행되고 있 으며 다양한 소재에 대한 탐색이 이루어지고 있다. 본 총설에서는 상용 블록 공중합체인 Polystyrene-b-poly(ethylene- co-butylene)-b-polystyrene (SEBS)를 기반으로 하는 음이온 교환막에 대한 연구에 대해 살펴보며 최신 연구 동향과 앞으 로 나아가야할 점에 대해 논하고자 한다.

PURPOSES : The objective of this study was to evaluate the effectiveness of dust removal by dust removal vehicles by the measuring dust load and PM10 concentrations on the sidewalks of block pavements. METHODS : Field experiments were conducted to determine a dust removal method suitable for the sidewalk conditions, as identified through a literature review. Data collection was followed by the evaluation of the sidewalk dust load with removal vehicles and analysis of the PM10 content within a service road. Moreover, an economic analysis was conducted based on the social costs of dust reduction. RESULTS : When cleaning a sidewalk block by spraying water, the contaminants in small gaps in the block pavement could be reduced, providing a potential solution to void clogging. The dust on the surface of the sidewalk was suspended from a paved road with a high level of traffic volume. Using sidewalk dust removal vehicles with sweeping, spraying water, and inhalation reduced the dust load and PM10 contents by more than 2 and 0.07g/m2, respectively. CONCLUSIONS : According to the economic analysis of the development of dust removal vehicles for sidewalks, the cost-benefit analysis method shows an input effect of 0.4, but if the reduction amount of fine particles such as PM2.5, further experiments are necessary to address the atmospheric fine dust concentrations resulting from cleaning sidewalk block pavements.

블록 매칭 및 3D 필터링(BM3D) 알고리즘은 단일 필터의 문제점을 보완하기 위하여 non-local means 기반으로 만들 어진 융합형 노이즈 제거 알고리즘이다. 하지만, 그 수식 인자의 조절에 관한 연구는 이루어지지 않고 있어 본 연구에서는 자기공명영상에서 발생하는 Rician 노이즈를 제거하기 위해 BM3D 알고리즘의 평활화 정도를 결정하는 노이즈 전력 스펙 트럼 밀도(noise power spectrum density,  )에 대한 최적화를 진행하고자 하였다. MRiLab 시뮬레이션 프로그램을 이 용하여 뇌 조직을 모사할 수 있는 뇌척수액(cerebrospinal fluid, CSF)/회색질(gray matter, GM)/백질(white matter, WM) 팬텀의 T1 강조영상을 획득하였고, 노이즈 레벨이 0.1, 0.15, 0.2, 0.25, 그리고 0.3인 Rician 노이즈를 각각 부가 한 후, BM3D 알고리즘의  값을 0.01부터 0.99까지 0.01씩 증가시키며 각각의 노이즈가 부가된 영상에 적용하였다. 정량 적 평가를 통해 최적화 값을 선정하기 위하여 CSF, GM, WM, 그리고 배경 영역에 관심 영역을 설정한 후 조직별 신호 대 잡음비(signal to noise ratio, SNR), 총 변동계수(coefficient of variation, COV), 그리고 평균 제곱근 오차(root mean square error, RMSE)를 측정하였다. 결과적으로, 조직별로 계산된 SNR, COV, 그리고 RMSE를 종합적으로 평가 했을 때 모든 조직에서 노이즈 레벨 0.1부터 0.3까지 증가함에 따라  값 또한 함께 증가하는 경향이 나타났으며 일정  값 이상에서는 노이즈뿐만 아니라 영상신호까지 함께 제거되어 개선 폭이 감소하는 것으로 관찰되었으며, 노이즈 레벨에 따라 각각 0.09, 0.13, 0.17, 0.21, 그리고 0.25의  값이 설정된 BM3D 알고리즘이 적용되었을 때 가장 합리적인 영상 특성을 보이는 것으로 나타났다. 결론적으로, 효과적인 노이즈 제거를 위해서 고정된 값이 아닌 노이즈 레벨에 따른 적합한 값을 적용해야 함을 증명할 수 있었다.

Predicting remaining useful life (RUL) becomes significant to implement prognostics and health management of industrial systems. The relevant studies have contributed to creating RUL prediction models and validating their acceptable performance; however, they are confined to drive reasonable preventive maintenance strategies derived from and connected with such predictive models. This paper proposes a data-driven preventive maintenance method that predicts RUL of industrial systems and determines the optimal replacement time intervals to lead to cost minimization in preventive maintenance. The proposed method comprises: (1) generating RUL prediction models through learning historical process data by using machine learning techniques including random forest and extreme gradient boosting, and (2) applying the system failure time derived from the RUL prediction models to the Weibull distribution-based minimum-repair block replacement model for finding the cost-optimal block replacement time. The paper includes a case study to demonstrate the feasibility of the proposed method using an open dataset, wherein sensor data are generated and recorded from turbofan engine systems.

High-temperature friction performances of graphite blocks (GBs) and zinc phosphate impregnated graphite blocks (IGBs) were evaluated under various friction temperatures. The surface of IGB exhibited extremely lower average friction coefficient values, that was 0.007 at 400 °C and 0.008 at 450 °C, in comparison to that of GB (0.13 at 400 °C and 0.16 at 450 °C, respectively). The worn surface of IGB in the high-temperature friction test was smoother and more complete than that of GB. The wear under high temperature and load caused the transformation of zinc pyrophosphate to zinc metaphosphate and the formation of a continuous large-area boundary lubrication layer combined with graphite and metallic element on the wear surface. The superior tribology property of IGB could be attributed to the digestion of iron oxides by tribo-chemical reactions and passivation of the exposed dangling covalent bonds. Specifically, the layered structure generated on the IGB wear interface effectively decreased the adhesive forces and prevented the surface from serious damage.

Background: The traditional treatment protocol in adhesive capsulitis cases is physical therapy agents and a home exercise program. The extensive majority of patients respond to conservative treatment, but the painful rehabilitation program makes it inconvenient for individuals to fully comply with the treatment. In order to reduce pain and spasm, intraarticular injections or suprascapular nerve block may be effective before the rehabilitation program. Objectives: To investigated the effect of suprascapular nerve block (SNB), which is added to standard physical therapy on pain, functionality and range of motion in patients with adhesive capsulitis (AC). Design: Retrospective study. Methods: This study included 46 patients who were treated for AC. Patients in both groups were given 15 season physical therapy and home exercise. The treatment group consisted of patients who underwent multiple SNB in addition to physical therapy and home exercise. Datas were analyzed retrospectively. Results: The Visual Analogue Scale (VAS), ROM, Shoulder Pain and Disability Index (SPADI) and Constant scores in both groups after treatment and at the third month follow-up (P<.001). In the comparison between the groups, it was determined that the improvement in VAS, ROM and SPADI scores in the treatment group at the 3-month control was statistically significant (P<.05). Conclusion: Multiple SNB added to physical therapy and home exercise program in cases of AC may be effective in terms of pain control, increasing joint range of motion and improving functionality.

PURPOSES : Abroad, road pavement materials vary depending on the speed and traffic volume of vehicles, but owing to the negative perception of block pavements, sidewalks, parking lots, and parks are primarily used in Korea. In addition, since speed restriction policies such as safety speed 5030 have been implemented recently, it is necessary to use block pavements for roadways, which are considered to have the effect of reducing speed. Therefore, it is necessary not only to actively discuss the introduction of block pavements for roadways but to continue research on the effectiveness of the performance evaluation and to change the perception of roads in Korea. METHODS : In this study, five indicators (surface damage, surface temperature, driving speed of vehicle, noise, and suspended dust) were selected for a sustainable road environment. The performance evaluation index of block pavement for roadways was decided according to the domestic and international literature, and the data were collected based on the evaluation index in the section with block pavement for roadways in Korea. RESULTS : The damage rate was calculated 0.35% according to the breakage of block and Maintenance Control Index(MCI) was ranked A~B even though the pavement was used for more than 4~5 years. The surface temperature of block pavement has a temperature reduction effect of 7 ℃ compared with ordinary asphalt pavement and a speed reduction of approximately 4 km/h on average; therefore, the traffic calming effect of block pavements can be expected. The noise of block pavement and asphalt pavement exhibited a similar level, and the noise level experienced by pedestrians did not change significantly as a result of frequency analysis. The measurement of road suspended dust around the road confirmed the possibility of reducing the concentration of road dust in the air owing to the smooth surface drainage and the results indicated the possibility. CONCLUSIONS : The results of this study are expected to contribute to the recognition and functional improvement of domestic block pavements by continuous monitoring to ensure the reliability of blocks. In addition, it is necessary to ensure the reliability of the quality and functional evaluation of paving materials through continuous on-site monitoring.

Artificial graphites have been used in various applications, for example, as anode materials for Li-ion batteries, C/C composites, and electrodes for aluminum smelting, due to their unique mechanical strength and high thermal and electrical conductivity. Artificial graphites can be manufactured by a series of kneading, molding, carbonization and graphitization processes with an additional impregnation process. In this study, the influence of the process variables in the kneading and carbonization/graphitization process on the properties of the resulting carbon block was systemically investigated. During the kneading process, the optimum kneading temperature was 90 °C higher than the softening point of the binder pitch; thus, the binder pitch reached its maximum fluidity. On the other hand, during the carbonization and graphitization process, the structural properties of carbon blocks prepared at different heat treatment temperatures were examined and their structural change and evolution were closely described according to the temperature and divided into low-temperature carbonization and high-temperature carbonization/graphitization. Based on this study, we expect to provide a better understanding of setting the parameters for thermally conductive carbon block manufacturing.