• 한국건설관리학회:학술대회논문집
• /
• 한국건설관리학회 2007년도 정기학술발표대회 논문집
• /
• pp.768-773
• /
• 2007

세계화 및 개방화에 능동적으로 대응할 수 있는 건설자재 정보속성 표준화는 건설산업 전반에 걸쳐 그 수요가 지속적으로 유지되고 있으며, 건설시장의 생산성에 획기적인 기여효과를 파생할 수 있는 기반기술이다. 건설자재 정보유통 활성화를 위해 건설자재 구매실무자를 대상으로 입수경로 및 정보속성을 조사하여 건설자재 정보제공체계의 현황을 분석하고, 이를 토대로 정보속성 개선점 및 활용도를 모색하여 표준화/정형화된 건설자재 일반정보 표준속성을 도출하고자 한다. 또한, 건설산업의 안정성 및 품질확보의 초석이 되는 품질정보 표준화를 위해 건설자재 품질인증 시험항목 분석을 수행하여 건설공정에 따라 정보속성을 분류하였으며, 이를 기반으로 품질정보 대표속성을 제시하고자 하였따. 건설자재 일반정보 속성도출의 논리성을 확립하고자 전자상거래를 위한 대표적 송성체계인 ECCMA와 ISO국제표준과의 호환성 검토를 기반으로 자재구매 실무자 200명을 대상으로 실태수요조사를 수행하여 통계적 분석을 수행하였으며, 품질정보속성 표준화의 체계성 확보를 위해 국제적으로 통용되고 있는 북미의 대표적인 분류체계인 Master Format(2004)을 준용하였다.

• 한국디지털건축인테리어학회논문집
• /
• 제5권2호
• /
• pp.29-35
• /
• 2005

The interest about noise and vibration which occurs in buildings is increasing by a living level elevation recently. Particularly, the vibration which occurs from the elevator cage of the building is possibility of damage to the users of the building continuously. So, the purpose of this study is a place where it examines closely the vibrating unit of the elevator and propose the countermeasure of it.

• 한국소음진동공학회논문집
• /
• 제25권4호
• /
• pp.238-246
• /
• 2015

A stepping motor is widely used to operate the elevation and azimuth stage of the X-band antenna with 2-axis gimbal system for effective image data transmission from a satellite to a ground station. However, such stepping motor also generates an undesirable micro-vibration which is one of the main disturbance sources affecting image quality of the high-resolution observation satellite. In order to improve the image quality, the micro-vibration isolation of the X-band antenna system is essential. In this study, the low rotational stiffness isolator has been proposed to reduce the micro-vibration disturbance induced by elevation direction operation of the X-band antenna. In addition, its structural safety was confirmed by the structure analysis based on the derived torque budget. The effectiveness of the design was also verified through the micro-vibration measurement test.

• Journal of Periodontal and Implant Science
• /
• 제39권3호
• /
• pp.311-320
• /
• 2009

Purpose: The aim of the present study was to analyze 7-year cumulative survival rate (CSR, %) of dental implants in the controlled diabetic patients and to evaluate the influence of the position, diameter and length of fixture, bone quality, age, gender and the method of maxillary sinus elevation on the survival rate. Methods: The data of 342 placed implants in the 104 diabetic patients collected between 1995 and 2007 at the Department of Periodontology in Yonsei University Hospital were analyzed. Results: Seven-year CSR of the 342 dental implants in the 104 controlled diabetic patients was 96.5%. The survival rates of the placed implants according the position have no statistically significant difference. The survival rates according to the length or diameter of the fixtures have no statistically significant difference. The survival rates according to the bone quality were 100% (Type I), 97.1% (Type II), 97.7% (Type III) and 85.7%(Type IV). The difference between the survival rate of Type I, II and III and that of Type IV was statistically significant. The survival rates according to patient gender were 96.8% (male), 95.5% (female). The survival rates according to patient age were 100% (${\leq}59$), 93.8% (${\geq}60$). The survival rates according to the method of sinus elevation in the maxillary posterior area were 96.8% (without sinus elevation), 92.9% (lateral approach) and 89.8% (crestal approach). Conclusions: Dental implants can be used successfully in the controlled diabetic patients. In case of upper posterior region which has poor bone density and older patients, the implant treatment should be more properly planed, executed, and followed-up.

• 한국지형학회지
• /
• 제23권3호
• /
• pp.67-78
• /
• 2016

Soil carbon(C) is an essential property for characterizing soil quality. Understanding spatial patterns of soil C is particularly limited for mountain areas. This study aims to predict the spatial pattern of soil C using terrain analysis in a steep mountainous area. Specifically, model performances and prediction uncertainties were investigated based on the number of resampling repetitions. Further, important predictors for soil C were also identified. Finally, the spatial distribution of uncertainty was analyzed. A total of 91 soil samples were collected via conditioned latin hypercube sampling and a digital soil C map was developed using support vector regression which is one of the powerful machine learning methods. Results showed that there were no distinct differences of model performances depending on the number of repetitions except for 10-fold cross validation. For soil C, elevation and surface curvature were selected as important predictors by recursive feature elimination. Soil C showed higher values in higher elevation and concave slopes. The spatial pattern of soil C might possibly reflect lateral movement of water and materials along the surface configuration of the study area. The higher values of uncertainty in higher elevation and concave slopes might be related to geomorphological characteristics of the research area and the sampling design. This study is believed to provide a better understanding of the relationship between geomorphology and soil C in the mountainous ecosystem.

• 한국관개배수논문집
• /
• 제18권1호
• /
• pp.25-32
• /
• 2011

In order to effectively manage the reservoir, reservoir water quality management should be based on physicochemical and configurational characteristics. In this research, correlation between factors affecting the reservoir water quality was examined. Chl-a and COD shows the highest positive correlation. Chl-a and T-P also has a high positive correlation, however Chl-a and T-N show lower correlation relatively. Even though T-N is an important factor for phytoplankton growth which increase Chl-a concentration, corelation of Ch1-a and T-N shows that enough nitrogen in the reservoir isn't no longer limiting factor. The age of reservoir can cause of increasing COD and SS. Embankment height and elevation of reservoirs shows strong negative correlation to water quality. That means reservoir which is higher embankment height and locate in higher elevations is less contaminated. Regression expression was derived with Chl-a and water quality parameters, and height of reservoir. Finally Chl-a was simulated using regression expression and it was a good approach to predict the Chl-a concentration.

• 대한토목학회논문집
• /
• 제33권4호
• /
• pp.1401-1411
• /
• 2013

호소형 하천으로 정체수역 특성을 갖는 서낙동강에서의 대저수문 유입량과 녹산수문 방류량은 오염총량관리 시행계획 대상유역인 낙본N 단위유역의 수질관리에 있어서 매우 중요한 영향을 미친다. 하지만 기준유량을 산정하기 위한 실측자료는 매우 부족하고, 대저수문과 녹산수문의 운영자료는 수문개도시 최대가능방류량만을 사용하고 있으므로 실측 방류량과는 많은 차이를 보이고 있다. 본 연구에서는 대저수문과 녹산수문의 운영자료를 수집하고, 이를 환경부 수질측정망 월별 수질변화와의 비교를 통해 분석하였다. 또한 대저수문과 녹산수문의 운영에 따른 서낙동강 본류의 비정상상태의 유량변화와 이에 따른 수질변화를 실측하였다. 낙동강 본류 수위, 서낙동강 수위, 조위 등의 영향을 받는 대저수문 유입과 녹산수문 방류에 의한 서낙동강 유량변화를 실측하였으며, 이는 대저수문과 녹산수문의 최적 운영을 통한 서낙동강의 수질 개선 대책 수립의 기초자료로 활용될 수 있을 것으로 판단된다.

• 대한공간정보학회지
• /
• 제13권3호
• /
• pp.3-13
• /
• 2005

본 연구의 목적은 공간데이터 제작과정의 품질관리방법을 정립하는데 있다. 이를 위하여 총 17개의 국내 공간데이터 품질관련 법규 및 주요 항측 업체를 대상으로 작업순서, 사용장비, 작업 전후의 결과물의 정확도를 중심으로 조사, 분석하였다. 조사, 분석한 내용을 기반으로 공간데이터의 구축공정을 '항공사진을 이용한 수치지도 신규제작', '기존 수치지도 수정제작', '수치표고모델 구축', '영상지도제작'에 의한 공간데이터 구축 공정을 표준화하였으며, 공정별로 생성되는 공간데이터의 품질을 체크할 수 있는 요소들을 정립하였다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2004년도 추계학술대회 논문집
• /
• pp.836-839
• /
• 2004

Qualitative elevation of products is very important Part. A business racking us brains to find for qualitative elevation of products. Recently, measurement accuracy of a non-contact 3D scanner has been rapidly improving. As a result, the number application cases of non-contact 3D scanners are increasing. A non-contact 3D scanner is capable of measuring a curved surface rapidly and has high resolution. It is more affordable and potable than the CMMs, It is therefore expected to be applied more frequently in more diverse industries. Automating the measuring process using a non-contact 3D scanner and developing a technology, which allows a user to measure easily, will eventually improve the quality of products. As their inspection and analysis processes improve.

• Journal of Platform Technology
• /
• 제11권4호
• /
• pp.13-18
• /
• 2023

3D content rendering is one of the important factors that give a sense of realism when creating content, and this process takes a lot of time. In this paper, we proposed a method to improve rendering performance by reducing the vast amount of 3D data in the web environment, and conducted a performance test using DEM and 3D model elevation data. As a result of the experiment, the digital elevation model showed faster performance than the Blender-based 3D modeling, but when the screen was moved using OrbitControl, the fps dropped momentarily. In the case of Terrain, if the range is limited to a speed that maintains 24 to 60 fps using frustum culling and LOD techniques, it is considered that a higher quality map can be produced than GeoTIFF.