• 한국건설관리학회논문집
• /
• 제20권3호
• /
• pp.64-76
• /
• 2019

노후 공동주택은 주차 공간이 부족하고, 경제수준 향상으로 인한 자가용보급 증가로 극심한 주차난을 겪고 있다. 주차 공간부족 문제를 해소하기 위한 방안으로 효율적인 리모델링 기술이 요구되고 있지만, 다양한 단지의 특성을 반영할 수 있는 리모델링 계획 기술 정립이 부족한 실정이다. 이 연구는 기술트리를 활용하여 주차장 확대 기술의 기능을 분석하고, 기능전개를 통하여 최종 기술을 도출하기 위하여 수행되었다. 주차장 확대 계획의 기능전개 결과, 5차 기능까지 전개하였고, 총 22가지 기술을 도출하였다. 전체 기술을 4가지로 분류하고, 지하 확대 기술은 4가지, 지하+지상 확대 기술은 12가지, 지상 확대 기술은 2가지, 지상 복합 확대 기술은 4가지로 나타났다. 주동 진입 계획의 기능전개 결과, 5차 기능까지 전개하고, 22가지의 기술로 도출하였다. 전체 기술을 4가지로 그룹핑 하고, 지하 직접 진입 기술은 4가지, 지하 간접 진입 기술은 11가지, 지상 직접 진입 기술은 3가지, 지상 간접 진입 기술은 4가지로 확인하였다. 사례검증을 통하여 리모델링 준공단지에 실제 적용된 세부 기술을 파악하고, 전문가 설문 및 면담조사를 실시하여 기술트리의 적정성을 검증하였다.

• 대한기계학회논문집
• /
• 제18권6호
• /
• pp.1582-1589
• /
• 1994

The characteristics Prandt1-Meyer expansion of supersonic flow with condensation through a wavy wall in a channel are investigated by experiment and numerical direct marching method of characteristics. In the present study, for the case of moist air flow in the type of indraft supersonic wind tunnel, the dependency of location of formation and reflection of the oblique shock wave generated by the wavy wall and the distribution of flow properties, on the specific humidity and temperature at the entrance of wavy wall and the attack angle of the wavy wall to the main stream is clarified by schlieren photograph, distribution of static pressure and Mach number, and plots of numerical results. Also, we confirm that the wavy wall plays an important key role in the formation of oblique shock wave, and that the effect of condensation on the flow field appears apparently.

• 한국GIS학회:학술대회논문집
• /
• 한국GIS학회 1999년도 추계학술대회 발표요약문
• /
• pp.21-25
• /
• 1999

Planning support systems(PSS) add more advanced spatial analysis functions than Geographic information systems(GIS) and intertemporal functions to the functions of spatial decision support systems(SDSS). This paper reports the continuing development of a PSS providing a framework that facilitates urban planners and civil engineers in conducting coherent deliberations about planning, design and operation & maintenance(O&M) of water-distribution networks for urban growth management. The PSS using dynamic optimization model, modeling-to-generate-alternatives, value engineering(VE) and life-cycle cost(LCC) can generate network alternatives in consideration of initial cost and O&H cost. Users can define alternatives by the direct manipulation of networks or by the manipulation of parameters in the models. The water-distribution network analysis model evaluates the performance of the user-defined alternatives. The PSS can be extended to include the functions of generating sewer network alternatives, combining water-distribution and sewer networks, eventually the function of planning, design and O&H of housing sites. Capacity expansion by the dynamic water-distribution network optimization model using MINLP includes three advantages over capacity expansion using optimal control theory(Kim and Hopkins 1996): 1) finds expansion alternatives including future capacity expansion times, sizes, locations, and pipe types of a water-distribution network provided, 2) has the capabilities to do the capacity expansion of each link spatially and intertemporally, and 3) requires less interaction between models. The modeling using MINLP is limited in addressing the relationship between cost, price, and demand, which the optimal control approach can consider. Strictly speaking, the construction and O&M costs of water-distribution networks influence the price charged for the served water, which in turn influence the. This limitation can be justified in rather small area because price per unit water in the area must be same as that of neighboring area, i.e., the price is determined administratively. Planners and engineers can put emphasis on capacity expansion without consideration of the relationship between cost, price, and demand.

• 대한치과교정학회지
• /
• 제52권5호
• /
• pp.334-344
• /
• 2022

Objective: This study aimed to systematically analyze the effect and stability of miniscrew-assisted rapid palatal expansion (MARPE) to provide a reference for the clinical treatment of patients with maxillary transverse deficiency (MTD). Methods: We searched PubMed, Science Direct, Web of Science, Embase, Cochrane Library, CNKI, and Wanfang Database for relevant studies published before February 18, 2021 and selected them according to the eligibility criteria. The Cochrane Handbook for Systematic Reviews (version 5.1.0) criteria were used for the quality assessment of randomized controlled trials, while the scoring protocol of the methodological index for non-randomized studies was used for non-randomized controlled trials. Statistical analysis was performed using the RevMan5.3 software. Results: All the included studies showed a relatively high success rate of expansion. The changes in both the intermolar and alveolar widths after MARPE were statistically significant. MARPE exhibited greater skeletal expansion effects than did conventional RPE. The midpalatal suture was opened in parallel after MARPE. A small amount of relapse was observed 1 year after expansion. MARPE caused tooth inclination and a decrease in alveolar height, but it was less significant than in conventional RPE. Conclusions: MARPE may be an effective treatment modality for patients with MTD. It causes great transverse skeletal expansion in late adolescence. In comparison to conventional RPE, MARPE has lower detrimental periodontal effects and has certain clinical advantages.

• 유통과학연구
• /
• 제13권12호
• /
• pp.65-71
• /
• 2015

Purpose - Domestic cooperatives tend to increase during the establishment of cooperatives and gradually through the basic law of social needs. However, only cooperatives' qualitative grow this secured without blessings, and their quantitative growth through government support is questionable. The purpose of this study is to analyze the agricultural cooperatives established through the Distribution System Cooperatives Basic Law, which was enacted in January 2012. Subsequently, establishing agricultural cooperatives was done briskly. However, cooperatives established rapidly after the founding of the Basic Law encountered problems. Research design, data, and methodology - To assess the performance of selected agricultural cooperatives, data were analyzed using the methodological Analytic Hierarchy Process (AHP) approach. The AHP is a set of systematic procedures to hierarchically analyze the elements of any problem. Using a survey on expertise, a series of comparative determinations of each pair is performed to evaluate the relative strengths and the strengths of the impact between elements within the hierarchy. A survey was conducted on 10 small agricultural cooperatives using AHP analysis for the examination. The purpose of such research and analysis is to recommend a direction for future policies aimed at small agricultural cooperatives. Result - This study applied three types of policy evaluation criterion, including market expansions, organizations, and cooperative projects, and 12 types of small agricultural cooperative policy measures. Market expansion policies for agricultural cooperatives are classified into four categories: school meals, direct transactions, shopping malls, and wholesale markets. Organizational policies for agricultural cooperatives are classified into four types: existing sales channel management, education, preventing free riding, and enlarging members. Cooperative project policies in agricultural cooperatives are classified into four policy areas: cooperation between cooperatives, community contribution, joint businesses, and government links. In this paper, the growth priority in agricultural cooperative policies is analyzed by applying policy evaluation criteria on the basis of a survey on expertise. The priorities of the policy program are also analyzed using a decision analytic hierarchy process. The results indicate that market expansion is the most important policy evaluation criterion therefore, improving direct transactions, school meals, management of existing sales channels, and shopping malls are crucial policy measures. In contrast, the cooperation of cooperatives, expansion of union members, and cooperation with the government were found to have low priority. Conclusions - Agricultural cooperatives should develop plans as follows. Small agricultural cooperatives need to secure school meals and direct transactions for market expansion, restructure marketing strategies to manage existing sales channels, and, finally, increase education and training for sustainable organizational development. This study has the following limitations. Because the subject of the investigation is a new cooperative, determining its sustainable growth is difficult. Therefore, through analysis and a continuous study of cooperatives, future research is expected to show that modifying the direction of agriculture cooperatives is necessary.

• 문화기술의 융합
• /
• 제4권3호
• /
• pp.241-246
• /
• 2018

영상 기기의 기계적인 문제로 인해 실험 데이터에 발생한 잡음으로 인한 인식 오류를 최소화하기 위해서 영상복원 과정을 거친다. 영상 복원 방법은 실험 데이터를 구성하는 각각의 픽셀에 대해 Direct Neighbor와 Indirect Neighbor의 개수와 위치를 조사해서 잡음을 해결한다. 결과적으로, 영상 복원 과정을 통해 실험 데이터에 발생한 잡음을 최대한 제거하고, 영역 단위로 학습 데이터와 실험 데이터의 차이를 계산해서 잡음에 의한 인식 오류 가능성을 낮춤으로써 만족할만한 인식 결과를 얻을 수 있다.

• 한국자동차공학회논문집
• /
• 제6권6호
• /
• pp.24-30
• /
• 1998

A directly coupled Boundary Element and Finite Element Model was applied to the dynamic analysis of a coupled acoustic silencer with vibratory wall. In this cupled BEM-FEM muffler model, the BEM model was used to discretize the acoustic cavity and the FEM model was used to discretize the vibratory wall structure. Then the BEM model was coupled with the FEM model. The results of the coupled BEM-FEM model for the dynamic analysis of the simple expansion type reactive muffler configurations with flexible walls were verified by comparing the predicted results to analytical solutions. In order to investigate the effects of the muffler's structural flexibility on its transmission loss(TL) characteristics, the results of the coupled BEM-FEM model in conjunction with the four-pole parameter theory were utilized. The muffler's TL characteristics using the BEM-FEM coupled model with flexible walls as compared to other muffler configurations was studied. Finally the muffler's TL values with respect to different wall's thickness are predicted and compared.

• 한국레이저가공학회지
• /
• 제11권2호
• /
• pp.26-32
• /
• 2008

Micro lens array (MLA) is widely used in information technology (IT) industry fields, for examples such as a projection display, an optical power regulator, a micro mass spectrometer and for medical appliances. Recently, MLA have been fabricated and developed by using a reflow method, micro etching, electroplating, micromachining and laser local heating. Laser local thermal-expansion (LLTE) technology demonstrates the formation of microdots on the surface of polymer substrate, in this paper. We have also investigated the new direct fabrication method of placing the MLA on the surface of a SU-8 photoresist layer. We have obtained the 3D shape of the micro lens processed by UV laser irradiation and have experimentally verified the optimal process conditions.

• 반도체디스플레이기술학회지
• /
• 제18권4호
• /
• pp.6-11
• /
• 2019

For a wider application of laser direct patterning, selective laser ablation of indium tin oxide (ITO) film on transparent oxide semiconductor (TOS) thin film was carried out using a diode-pumped Q-switched Nd:YVO₄ laser at a wavelength of 1064 nm. In case of the laser ablation of ITO on indium gallium zinc oxide (IGZO) film, both of ITO and IGZO films were fully etched for all the conditions of the laser beams even though IGZO monolayer was not ablated at the same laser beam condition. On the contrary, in case of the laser ablation of ITO on zinc oxide (ZnO) film, it was possible to etch ITO selectively with a slight damage on ZnO layer. The selective laser ablation is expected to be due to the different coefficient of thermal expansion (CTE) between ITO and ZnO.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집D
• /
• pp.708-714
• /
• 2001

Although LP gas has lots of advantages, there has been limitation in application for automotive engine due to the several disadvantages, such as power decrease, complex fuel supply unit, and back fire etc. However LP gas direct injection engine has possibility to solve the problems above mentioned. LEM(Light Extinction Method) was employed for analysis of spacial and temporal distribution of LP gas which is directly injected into combustion chamber under various pressure and temperature conditions. The results from CVC(Constant Volume Chamber) were compared to those of RICEM(Rapid Induction, Compression and Expansion Machine) which simulate early- and late injection of direct injection engine. LPG fuel spray is affected by temperature and pressure in evaporation characteristics but it is more benefit to direct injection engine in every way such as, fuel distribution, evaporating speed and well wetting reduction.