• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.182-186
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• 2011

Ejector-diffuser system has long been used in many diverse fields of engineering applications and it has advantages over other fluid machinery, because of no moving parts and structural simplicity. This system makes use of high-pressure primary stream to entrain the low-pressure secondary stream through pure shear actions between two streams. In general, the flow field in the ejector-diffuser system is highly complicated due to turbulent mixing, compressibility effects and sometimes flow unsteadiness. A fatal drawback of the ejector system is in its low efficiency. Many works have been done to improve the performance of the ejector system, but not yet satisfactory, compared with that of other fluid machinery. In the present study, a mixing guide vane was installed at the inlet of the secondary stream for the purpose of the performance improvement of the ejector system. A CFD method has been applied to simulate the supersonic flows inside the ejector-diffuser system. The present results obtained were validated with existing experimental data. The mixing guide vane effects are discussed in terms of the entrainment ratio, total pressure loss as well as pressure recovery.

• KIEAE Journal
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• 제7권1호
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• pp.23-31
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• 2007

This study aims to evaluate the illuminance performance of sloped light guide with automated venetian blind systems. For the purpose, a mock-up model was constructed as a prototype of Korean office building with $12.0m{\times}7.3m{\times}3.7m$ ($w{\times}d{\times}h$) and south facing side-window mounted between the clerestory window($2.0m^2$) and the view window($5.6m^2$). The light guide of 1.28m deepth and $29^{\circ}$ tilted angle, is covered with 0.6mm galvanized steel sheet and 97% reflective film. To protect the room from low solar angle, a blind systems, 0.15m deepth and $30^{\circ}$ automated slat angle was installed. To assess illuminance performance, the totally 37 measuring points for illuminance were monitored. For the detailed analysis, photometric sensors were installed at work-plane (8 points), wall (7 points), ceiling (3points), and exterior horizontal illuminance (1 point) respectively. The performance was measured under clear sky and is monitored by Agilent data logger, photometric sensor Li-cor and the Radiant Imaging ProMetric 1400. Comparisons of light factor and uniformity are discussed.

• The Journal of Korean Physical Therapy
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• 제31권4호
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• pp.184-192
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• 2019

Purpose: This study was conducted to review the curriculum and license examination of physical therapists in the United States. Methods: The doctor of physical therapy (DPT) curriculum was evaluated by a review Course Work Tool version 6 (CWT6) data and current physical therapy licensure examination (National Physical Therapy Exam, NPTE) category in the United States. Results: The results indicated that they were required to meet the doctor of physical therapist degree based on 'Guide to Physical Therapist Practice' of American Physical Therapy Association (APTA). This includes general education in the areas of communications and humanities, physical science, biological science, social and behavioral science, and mathematics. A minimum of one course must be completed successfully in each area of general education. Moreover, there should be at least 68 didactic credits of professional education and 22 clinical education credits, which is a minimum of two full-time clinical internships with no less than 1050 hours in total, which were supervised by a physical therapist. Regarding the physical therapy licensure examination, National Physical Therapy Exam (NPTE, 2016) consisted of a physical therapy examination (26.5%), evaluation, differential diagnosis, baseline of prognosis (32.5%), intervention (28.5%), protection, responsibility, and research (6.5%) based on the 'Guide to Physical Therapist Practice'. Conclusion: Based on the study results provided above, it is considered a standard to meet domestic reality as the Guide to Physical Therapist Practice of APTA for South Korean physical therapists.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1245-1248
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• 2004

This paper presents a new technique to analyze data on the coordinate x, y, z and apply these data to design the motion control to improve the efficiency of the engraving machine so that it can engrave accordingly in 3 dimensions. First, the tool path on the x-y plane is analyzed to be synchronized with the z-axis. The digital data is then sent to the motion control to guide the movement of the engrave point on the x-y plane. Tool path moves along the x-axis with zero degree and different values of the y-axis according to the coordinate of the digital data and the analysis along z-axis to determine the depth for engraving. The depth can be specified from the gray level with the 256 levels of resolution. The data obtained includes the distances on x-axis, y-axis, and z-axis, the acceleration of the engrave point's movement, and the speed of the engrave point's movement. These data is then transfered to the motion control to guide the movement of the engrave point along the z-axis associated with the x-y plane. The results indicate that engraving using this technique is fast and continuous. The specimen obtained looks perfect in 3D view.

• 한국정보통신학회논문지
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• 제24권4호
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• pp.481-488
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• 2020

최근 실감형 콘텐츠인 가상현실, 증강현실, 혼합현실 기술이 여행 및 관광 산업에서 확산되는 추세이며 다양한 스마트 관광 AR, VR 콘텐츠가 개발되고 있다. 기존에 사람들이 여행을 위해 책자나 인터넷을 주로 활용했지만 앞으로 VR, AR, MR 기술이 문화 여가 콘텐츠 소비에 더 활용될 것으로 보인다. 본 연구에서는 스마트 관광의 활성화를 위해 개발한 혼합현실 백제 능사 문화유산 현장 가이드 시스템을 설명한다. 본 연구에서는 몰입적인 혼합 현실 HMD를 사용하여 방문객들에게 백제 능사의 역사적, 문화적, 건축적 가치를 가상 체험을 통하여 보다 직관적이며 효과적으로 정보를 전달 받을 수 있도록 하였다. 문화유적 현장 가이드 시스템 모듈은 다양한 메타 데이터 서비스를 지원하며 스크립트 방식으로 지정하여 혼합현실 콘텐츠 개발에 쉽게 사용될 수 있다. 이 연구는 혼합 현실 기반 스마트 관광 콘텐츠 개발에 기여할 수 있을 것으로 기대한다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제25권2_spc호
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• pp.28-54
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• 2020

Even though a systematic sampling approach is very crucial in both the general and detailed investigation phases to produce the best conceptual site model for contaminated sites, the concept is not yet established in South Korea. The U.S. Environmental Protection Agency (EPA) issued the 'Strategic Sampling Approaches Technical guide' in 2018 to help environmental professionals choose which sampling approaches may be needed and most effective for given site conditions. The EPA guide broadly defines strategic sampling as the application of focused data collection across targeted areas of the conceptual site model (CSM) to provide the appropriate amount and type of information needed for decision-making. These strategic sampling approaches can prevent the essential data from missing, minimize the uncertainty of projects and secure the data which are necessary for the important site-decisions. Furthermore, these provide collaborative data sets through the life cycle phases of projects, which can generate more positive proofs on the site-decisions. The strategic sampling approaches can be divided by site conditions. This technical guide categorized it into eight conditions; High-resolution site characterization in unconsolidated environments, High-resolution site characterization in fractured sedimentary rock environments, Incremental sampling, Contaminant source definition, Passive groundwater sampling, Passive sampling for surface water and sediment, Groundwater to surface water interaction, and Vapor intrusion. This commentary paper introduces specific sampling methods based on site conditions when the strategic sampling approaches are applied.

• Management Science and Financial Engineering
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• 제15권1호
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• pp.81-96
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• 2009

Data mining, specially clustering is one of exciting research areas for ant based algorithms. Ant clustering algorithm, however, has many difficulties for resolving practical situations in clustering. We propose a new grid-based ant colony algorithm for clustering of data. The previous ant based clustering algorithms usually tried to find the clusters during picking up or dropping down process of the items of ants using some stigmergy information. In our ant clustering algorithm we try to make the ants reflect neighborhood information within the storage nests. We use two ant classes, search ants and labor ants. In the initial step of the proposed algorithm, the search ants try to guide the characteristics of the storage nests. Then the labor ants try to classify the items using the guide in-formation that has set by the search ants and the stigmergy information that has set by other labor ants. In this procedure the clustering decision of ants is quickly guided and keeping out of from the stagnated process. We experimented and compared our algorithm with other known algorithms for the known and statistically-made data. From these experiments we prove that the suggested ant mining algorithm found the clusters quickly and effectively comparing with a known ant clustering algorithm.

• 한국컴퓨터정보학회논문지
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• 제23권8호
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• pp.95-99
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• 2018

This research is related to GPS(global positioning system) enabled device navigation service and consists of two parts. The first is the logic that records the route guidance video and records GPS information in time, and the second is the logic that outputs the created video data based on real time GPS. The recording logic first determines the origin and destination, records the video from the origin to the destination and it adjusts the speed of the image in a specific area so that the user can see it easily. And insert ancillary information and advertisements that can help guide the route. In the output logic, we provide navigation services using the video and GPS data tables we created, and it receives user's GPS information in real time and corrects it based on the recent user location to reduce errors. This provides local guidance services to people who lack language skills like foreigners.

• 한국CDE학회논문집
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• 제14권6호
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• pp.355-363
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• 2009

The purpose of this study is to suggest development direction of open BIM. To achieve this purpose, the authors have investigated application status and current problems of open BIM through question survey to design firm which is introducing or plan BIM. In addition, the authors have suggested improvement way about current problems of BIM application such as BIM standard guide, reference of practical application examples, BIM library, data interoperability between software, improvement of BIM software function and performance that is deducted through question survey.

• Korean Journal of Radiology
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• 제22권10호
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• pp.1587-1593
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• 2021