• Archives of Plastic Surgery
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• 제40권3호
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• pp.203-208
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• 2013

Background Preoperative volume assessment is useful in breast reconstruction. Magnetic resonance imaging (MRI) and mammography are commonly available to reconstructive surgeons in the care of a patient with breast cancer. This study aimed to verify the accuracy of breast volume measured by MRI, and to identify any factor affecting the relationship between measured breast volume and actual breast weight to derive a new model for accurate breast volume estimation. Methods From January 2012 to January 2013, a retrospective review was performed on a total of 101 breasts from 99 patients who had undergone total mastectomy. The mastectomy specimen weight was obtained for each breast. Mammographic and MRI data were used to estimate the volume and density. A standard statistical analysis was performed. Results The mean mastectomy specimen weight was 340.8 g (range, 95 to 795 g). The mean MRI-estimated volume was $322.2mL^3$. When divided into three groups by the "difference percentage value", the underestimated group showed a significantly higher fibroglandular volume, higher percent density, and included significantly more Breast Imaging, Reporting and Data System mammographic density grade 4 breasts than the other groups. We derived a new model considering both fibroglandular tissue volume and fat tissue volume for accurate breast volume estimation. Conclusions MRI-based breast volume assessment showed a significant correlation with actual breast weight; however, in the case of dense breasts, the reconstructive surgeon should note that the mastectomy specimen weight tends to overestimate the volume. We suggested a new model for accurate breast volume assessment considering fibroglandular and fat tissue volume.

• 토지주택연구
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• 제2권2호
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• pp.145-155
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• 2011

It is very important for successful construction to estimate the soil volume conversion factor of domestic weathered ground accurately and reasonably. However, it is very difficult to quantify the weathering degree of weathered ground at the field, so that the soil volume conversion factor used in Korea is often dependent upon the standard of foreign countries. Besides, the soil volume conversion factor of domestic weathered ground has been rarely studied and the use and accuracy of the soil volume conversion factor have been questioned persistingly. This study suggests a simple but robust method for estimating the soil volume conversion factor and measuring the weathering degree reasonably, and attempts to establish the utilization of a soil volume conversion factor measurement system based on experimental and analytical results. We made relationship between electrical resistivity and weathering degree presented from weathering index obtained through laboratory tests using field samples, and an estimation method of in-situ weathering degree for granites and a calculation method of soil volume conversion factor using electrical resistivity. And also, we suggested the photogrametry measurement-equipment system for measuring the volume of cargo box and the application plan of stand equipment and RFID for calculating the earth volume and distinguishing buggies in order to design the measurement system for soil volume conversion factor applicable to the field. Ultimately, the Weathered Earth-work Management Program (WEMP) was developed, so field managers may easily obtain the information about earth volume and soil volume conversion factor at the weathered ground.

• 지적과 국토정보
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• 제47권1호
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• pp.111-126
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• 2017

소형 무인항공시스템(무인항공기 플랫펌과 센서의 융합기술, 'sUAS')은 정확성, 경제성 및 운용면의 무궁한 잠재성으로 여러 건설현장에서 새로운 응용이 창출되면서 활용이 점차 확산되고 있다. 본 연구의 목적은 소형 UAS에 의한 토공량 산정의 타당성을 검토하는 것이다. 이를 위해 시흥시 소재 배곧생명공원 내 위치한 대략 $270m{\times}300m{\times}20m$ 규모의 원추형 성토부를 대상으로 소형무인항공기를 활용하여 영상을 취득한 후, UAS 영상해석을 통해 산출된 토공량을 GNSS Network-RTK 지상측량에 의한 토공량과 정량적으로 비교분석하였다. 연구결과, 무인항공시스템 자료와 GNSS Network RTK 자료에 의한 토공량의 편차가 2% 이하였고 특히, 작업의 편이성, 신속성 및 경제성 면에서 소형 UAS 영상기반 토공량 산정의 효용성을 입증할 수 있었다. 따라서, 식생높이의 산정방안이 보완된다면 중 소규모 현장의 토공량 산정은 물론 3차원 지형공간정보 생성 분야에 무인항공영상의 응용이 유용할 것으로 기대된다.

• 한국산림과학회지
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• 제96권3호
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• pp.362-368
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• 2007

본 연구는 잣나무와 낙엽송을 대상으로 흉고직경급에 따른 임목의 용도별 이용재적 및 목재수율을 산출하기 위해 수행되었다. 먼저 기존에 개발된 수간곡선, 수고 추정식을 이용하여 입목의 형상에 따른 수간 재적량을 산출하였다. 그리고 일반용재와 펄프재의 이용재적 및 조재수율, 일반용재를 판재 및 각재로 가공했을 때 제재목의 이용재적 및 조재수율을 직경급별로 산출하였다. 연구결과에 따르면 수간재적에 있어서 낙엽송의 재적이 잣나무보다 동일한 흉고직경급에 있어서 23~38% 높게 나타났다. 일반용재 생산은 2개 수종 모두 흉고 직경급 18 cm부터 가능하였다. 또한 일반용재와 펄프재용 원목의 조재수율 합계는 흉고직경이 커지는 초기에 급격하게 증가하였고 잣나무의 경우 흉고직경 26 cm에서 90%, 낙엽송의 경우 흉고직경 38 cm에서 88%로 최대로 나타났다. 한편 판재의 조재수율은 23~56%, 각재는 그 생산크기가 커질수록 조재수율이 떨어지는 것으로 나타났다. 이 연구의 결과는 산림의 이용재적 산출 및 임목평가 그리고 제재목의 결정에 활용될 수 있을 것이다.

• 한국시스템다이내믹스연구
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• 제15권3호
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• pp.5-36
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• 2014

The purpose of this paper is to develop a System Dynamics model for estimating the volume of forest resources in the future and simulating the volume of function of public benefit linked to forest resources in dynamic manner. Also it is to analyze the impact when the volume of forest land conversion is controlled by policy using the SD model. The analysis was done at nation-wide for the simulation period 2000 to 2040. Estimated forest area was 6.2 million ha and estimated growing stock was $4.7\;billion\;m^3$ in 2040 from the future forecast without policies. Changing of forest resources, 13.9 billion tons of forest-ground-water storage was estimated, $1.8\;million\;m^3$ of erosion control of forest was estimated and 377 million tons of $CO_2$ absorption was estimated. As a result of simulation with two alternatives, forest area was less reduced and growing stock was bigger than do nothing policy. Also, function of public benefit reflected by changes of forest resources was enhanced. This study contributes to estimate the quantitatively measured volume of forest resources and function of public benefit over the 30 years in Korean forest land in scientific way. Using this SD model, decision maker would develop forest land policies more delicately for deserving forest resources and increasing the volume of function of public.

• 반도체디스플레이기술학회지
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• 제18권3호
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• pp.66-71
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• 2019

In shape from focus (SFF) methods, the quality of image focus volume plays a vital role in the quality of 3D shape reconstruction. Traditionally, a linear 2D filter is applied to each slice of the image focus volume to rectify the noisy focus measurements. However, this approach is problematic because it also modifies the accurate focus measurements that should ideally remain intact. Therefore, in this paper, we propose to enhance the focus volume adaptively by applying 3-dimensional weighted least squares (3D-WLS) based regularization. We estimate regularization weights from the guidance volume extracted from the image sequences. To solve 3D-WLS optimization problem efficiently, we apply a technique to solve a series of 1D linear sub-problems. Experiments conducted on synthetic and real image sequences demonstrate that the proposed method effectively enhances the image focus volume, ultimately improving the quality of reconstructed shape.

• 한국환경과학회지
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• 제18권7호
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• pp.747-754
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• 2009

In this study, which aims to estimate the volume of greenhouse gas emitted by road transportation vehicles in Changwon City, the emission rate was calculated on the basis of the actual traffic volume measured at major crossroads and compared with the results obtained from the methodology used to estimate the greenhouse gas emissions of road transportation provided in the IPCC 2006 GL guidelines (Tier 1, Tier 3). Analysis of the results of the comparison showed that the Tier 1 methodology, which was applied in the estimation of the rate of greenhouse gas emissions, carries a high probability of underestimation, while the Tier 3 methodology carries a relatively high probability of overestimation. Therefore, when considering the assignment of permissible rates of emission to local governments, the application of the methodology, i.e. whether one uses Tier 1 or Tier 3, may result in a large difference in the rate of allowable emissions. It is suggested that a method based on the actual volume of traffic would be the most reasonable one with regard to the development of a realistic plan.

• 한국산림과학회지
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• 제83권4호
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• pp.521-530
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• 1994

재적식(材積式)은 보통 흉고직경과 수고의 함수로 표현되는데, 회귀분석(回歸分析)을 통해 정확도가 높은 식이 주로 채택되고 있다. 우리나라에서도 지금까지 흉고직경(D)과 수고(H)를 독립변수로 하는 지수식(指數式)($V=aD^bH^c$)으로 각 수종에 대한 일반(一般)재적식을 유도하고 있다. 본 연구에서는 강원도 지방내의 홍천, 정선, 명주, 원주, 영월지역에 대한 간곡선식(幹曲線式)을 지역별로 유도하고, 이 간곡선식의 회전체(回轉體) 적분(積分)을 통해 지역별 재적을 직접 추정할 수 있는 간곡선 및 재적식 모델을 마련하였다. 조제된 모델에 의해 지역별로 추정된 재적은 기존의 강원도 지방 소나무재적표에 의해 추정된 재적에 비해 정확도가 높았다. 또한 지역간곡선식에 의해 유도된 간곡선의 형태는 지역에 따라 서로 달랐으며, 특히 영월지역과 원주지역의 수간은 다른 지역에 비해 수간상부에서 가늘게 발달하는 것으로 나타났다. 이와같은 간곡선의 다양한 형태는 재적추정에 있어서도 지역간 차이를 유발하였다.

• Archives of Plastic Surgery
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• 제45권4호
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• pp.333-339
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• 2018

Background Flap volume is an important factor for obtaining satisfactory symmetry in breast reconstruction with a transverse rectus abdominis myocutaneous (TRAM) free flap. We aimed to develop an easy and simple method to estimate flap volume. Methods We performed a preoperative estimation of the TRAM flap volume in five patients with breast cancer who underwent 2-stage breast reconstruction following an immediate tissue expander operation after a simple mastectomy. We measured the height and width of each flap zone using a ruler and measured the tissue thickness by ultrasound. The volume of each zone, approximated as a triangular or square prism, was then calculated. The zone volumes were summed to obtain the total calculated volume of the TRAM flap. We then determined the width of zone II, so that the calculated flap volume was equal to the required flap volume ($1.2{\times}1.05{\times}$the weight of the resected mastectomy tissue). The TRAM flap was transferred vertically so that zone III was located on the upper side, and zone II was trimmed in the sitting position after vascular anastomosis. We compared the estimated flap width of zone II (=X) with the actual flap width of zone II. Results X was similar to the actual measured width. Accurate volume replacement with the TRAM flap resulted in good symmetry in all cases. Conclusions The volume of a free TRAM flap can be straightforwardly estimated preoperatively using the method presented here, with ultrasound, ruler, and simple calculations, and this technique may help reduced the time required for precise flap tailoring.

• Computers and Concrete
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• 제25권5호
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• pp.433-445
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• 2020

A method is proposed in this paper to estimate the workability of self-compacting concrete (SCC) in different mixing conditions with different mixers and mixing volumes by recording the mixing process based on deep learning (DL). The SCC mixing videos were transformed into a series of image sequences to fit the DL model to predict the SF and VF values of SCC, with four groups in total and approximately thirty thousand image sequence samples. The workability of three groups SCC whose mixing conditions were learned by the DL model, was estimated. One additionally collected group of the SCC whose mixing condition was not learned, was also predicted. The results indicate that whether the SCC mixing condition is included in the training set and learned by the model, the trained model can estimate SCC with different workability effectively at the same time. Our goal to estimate SCC workability in different mixing conditions is achieved.