회전분리망 흡착선별기의 순환 굵은골재 이물질 제거효율에 관한 연구

조성광(Sungkwang Cho),김규용(Gyuyong Kim),김경욱(Kyungwuk Kim),선상원(Sangwon Seon),박진영(Jinyoung Park) 한국건설순환자원학회 2021 한국건설순환자원학회 논문집 Vol.9 No.1

건설폐기물에서 발생하는 순환골재의 분류 과정에서 발생하는 이물질을 순환골재 출하 전에 회수하기 위하여 회전분리망 흡착 선별기를 설계 및 제작하였다. 제작된 선별기의 성능을 평가하기 위하여, 순환골재에서 자체적으로 회수한 이물질 종류에 따라, 아크릴을 사용하여 규격화된 이물질 샘플을 제작하고, 선별기에서 작동하는 흡입팬의 제어주파수 및 분리망의 흡입구 위치에 따른 선별효율과 순환골재의 오분류율을 평가하여 적절한 운전점을 평가하였다. 순환골재 및 이물질을 입자로 가정한 유동해석을 통해 예측된 선별기의 운전점에서의 분류효율을 평가하였다. 성능 시험 결과 컨베이어 밸트와 흡입구의 거리가 0.2m일 때 95%의 선별효율을 보이는 것으로 나타났으나, 순환골재의 오분류율이 2% 이상으로 선별효율과 2% 이하의 오분류율을 만족하는 운전점은 흡입구 거리 0.254m에서 제어주파수 58Hz으로 나타났다. 유동해석 결과 이물질 선별기에서 순환골재의 오분류는 나타나지 않았다. 기존 순환골재 생산공정에서 이물질 저감을 위해 설치식으로 운용이 가능한 회전분리망을 이용한 풍력 선별시스템을 구축하였다. Aggregate waste separator with rotating separating net was designed for applying classification process of construction waste. In order to evaluate the performance of the aggregate waste separator, according to the type of waste, standardized waste samples are prepared using acrylic. The appropriate operating point was evaluated by the classification efficiency and misclassification rate of recycled aggregate according to the control frequency of the blower operating and inlet position of the separating net. The classification efficiency at the operating point of the aggregate waste separator was evaluated through flow analysis assuming recycled aggregate and waste sample as particles. As a result of the performance test, when the distance. between the conveyor belt and the inlet was 0.2m, the classification efficiency was 95%, but the misclassification rate of recycled aggregate was 2% or more, which satisfies the classification efficiency and the misclassification rate of less than 2%. The operating point was shown at a control frequency of 58Hz at a suction distance of 0.254m. As a result of flow analysis, there was no misclassification of recycled aggregate. In order to reduce construction waste in the existing recycled aggregate production process, adsorption system using a rotating separating net that can be operated as an installation type was built.

목적 조선어문교육이 직면한 문제 및 조선어문교원의 상응한 자세

김승광(Kim Sungkwang) 길림성민족사무위원회 2011 중국조선어문 Vol.170 No.-

블록체인 기술 기반의 주주총회 전자투표에 관한 연구

김석(Seog Kim),진성광(Sungkwang Jeen),김혜경(Hyekyung Kim),최정일(Jeongil Choi) 한국IT서비스학회 2020 한국IT서비스학회지 Vol.19 No.3

Electronic voting is one of information technology service to handle a wide range of functions, including registration, certification, input and results of voting, using electronic technology, depending on the degree of automation. It helps voters exercise their voting rights not only for individual suffrage but also for major corporate decisions as shareholders by expressing their opinions regardless of geographical and time constraints. Such electronic voting helps open and expand voting participation, but on the contrary, it is possible to identify who voted and what kind of vote, such voting cannot guarantee confidentiality. Therefore, if blockchain technology is applied to electronic voting, it can increase the speed of processing and confidentiality by encrypting voting information. In this regard, the study aims to identify institutional issues on how electronic voting can be activated at a company s shareholders meeting, and to find ways to overcome the limitations of existing electronic voting by utilizing the technical characteristics of blockchain. This study proposes a consortium-type blockchain-based electronic voting system to enhance the convenience and reliability of electronic voting for shareholders meetings. In addition, this paper suggests how to enhance shareholders profits through electronic voting at shareholders meetings, as well as its policy measures and future improvements.

LPG 충전소용 관제시스템 개발

조범석(Beomsek, Cho),김승광(Sungkwang Kim),김성태(Sungtae Kim),김종민(Jongmin Kim) 한국가스학회 2017 한국가스학회 학술대회논문집 Vol.2017 No.11

장면 문맥정보를 이용한 실시간 전방차량 검출

전성광(Quan Chengguang Sungkwang),김경일(Kim Kyung-Il),김원태(Kim Won-Tae),정선태(Chung Sun-Tae),조성원(Cho Seongwon) 한국통신학회 2011 한국통신학회 학술대회논문집 Vol.2011 No.2

물질의 B-H 곡선에 따른 솔레노이드 밸브의 흡입력 특성 전자기적 수치 해석

조성광(Sungkwang Cho),김진용(Jinyoung Kim),나병철(Byungchul Na),설승윤(Seungyun Seol) 한국자동차공학회 2016 한국자동차공학회 부문종합 학술대회 Vol.2016 No.5

In this paper, we perform a three-dimensional electromagnetic finite element numerical analysis applied axially symmetrical shape of a typical solenoid valve. parts of the solenoid valve Inner Yoke, Outer Yoke, Armature was to change the material of the attraction force characteristics according to identify current and the stator and the plunger clearance derives an analysis result. According to an analysis result, attraction force in increasing as clearance decreasing and property of b-h curve greater. Especially, it was figured out that the armature made of materials with better B-H curve characteristics increases the attraction force more than the armature made of the same material as the Inner and Outer Yokes.

유한요소해석을 통한 Rack housing 설계변경에 따른 압축하중 특성 연구

조성광(Sungkwang Cho),김진용(Jinyoung Kim),나병철(Byungchul Na) 한국자동차공학회 2017 한국자동차공학회 부문종합 학술대회 Vol.2017 No.5

귀금속계열 WGS 촉매 연구

임성광(Sungkwang Lim),배중면(Joongmyeon Bae),김선영(Sunyoung Kim) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.5

Water gas shift reactor in fuel processing is an important part that converts carbon monoxide into hydrogen. Fuel processing system for PEMFC usually has two stages of WGS reactors, which are high temperature and low temperature shifter. In this study we prepared noble metal catalysts and compared their performances with that of a commercial iron chromium oxide catalyst. Noble metal catalysts and the commercial catalyst showed quite different temperature dependence of carbon monoxide conversion. The conversion of carbon monoxide at the commercial catalyst was very low at medium temperature(~300℃) and increased rapidly as temperature increased while the conversion at noble metal catalysts was high in the medium temperature range and decreased as temperature increased, which is thermodynamically expected. Their characteristics agreed well with the literature published, and we are accomplishing further study for improvement of the noble metal catalysts.

4개 이상의 다발성 전이성 뇌종양의 정위적 방사선수술과 전뇌 방사선조사의 비교

김철진(Cheoljin Kim),백미영(Miyoung Baek),박성광(Sungkwang Park),안기정(Kijung Ahn),조흥래(Heunglae Cho) 대한방사선종양학회 2009 Radiation Oncology Journal Vol.27 No.3

목 적: 4개 이상의 다발성 전이성 뇌종양에서 정위적 방사선수술의 효용성에 대해서 검증하기 위하여 후향적으로 시행하였다. 대상 및 방법: 2004년 1월부터 2006년 12월까지 본원에서 4개 이상의 다발성 전이성 뇌종양으로 진단되어 정위적 방사선수술을 받은 29명의 환자와 전뇌 방사선조사를 받은 39명의 환자를 대상으로 후향적으로 분석하였다. 소세 포 폐암과 흑색종으로 진단받은 환자는 제외하였고, 원발 병소는 정위적 방사선수술군에서는 폐암이 69.0%, 유방암이 13.8%였고, 전뇌 방사선조사군에서는 폐암이 64.1%, 유방암이 15.4%, 대장-직장암이 12.8%였다. 정위적 방사선수술은 감마나이프를 이용하여 시술하였고, 50% 등선량 곡선에 10∼20 Gy를 1회 조사하였다. 전뇌 방사선조사는 30 Gy, 10회 분할조사 하였다. 치료 후 뇌 자기공명영상 또는 조영 증강 컴퓨터 단층촬영을 시행하여 두 군에서 치료 후 전이성 뇌종양이 진행되기까지 걸린 기간과 전체 생존율에 대해 비교 분석하였다.결 과: 두 군의 추척 관찰 기간은 2개월에서 23개월이었고, 정위적 방사선수술군의 추적관찰 기간 중앙값은 5개월,전뇌 방사선조사군의 경우에는 6개월이었다. 뇌전이 숫자의 중앙값이 정위적 방사선수술군에서는 6개, 전뇌 방사선조사군에서는 5개였다. 전이성 뇌종양의 진행을 억제하는 효과를 보여주는 두개내 무진행 생존율은 정위적 방사선수술군에서는 5.1개월, 전뇌 방사선조사군에서는 6.1개월이었고, 정위적 방사선수술을 시행한 환자들의 전체 생존율의 중앙값은 5.6개월, 전뇌 방사선조사를 시행한 환자들은 7.2개월이었다. 결 론: 4개 이상의 다발성 뇌 전이에 있어서 정위적 방사선수술은 전뇌 방사선조사에 비해 그 효용성이 낮으며 전 뇌 방사선조사를 시행하는 것이 바람직할 것으로 판단된다. Purpose: This study was a retrospective evaluation of the efficacy of stereotactic radiosurgery (SRS) in patients with >4 metastases to the brain. Materials and Methods: Between January 2004 and December 2006, 68 patients with ≥4 multiple brain metastases were included and reviewed retrospectively. Twenty-nine patients received SRS and 39 patients received whole brain radiotherapy (WBRT). Patients with small cell lung cancers and melanomas were excluded. The primary lesions were non-small cell lung cancer (69.0%) and breast cancer (13.8%) in the SRS group and non-small cell lung cancer (64.1%), breast cancer (15.4%), colorectal cancer (12.8%), esophageal cancer (5.1%) in the WBRT group. SRS involved gamma-knife radiosurgery and delivered 10∼20 Gy (median, 16 Gy) in a single fraction with a 50% marginal dose. WBRT was delivered daily in 3 Gy fractions, for a total of 30 Gy. After completion of treatment, a follow-up brain MRI or a contrast-enhanced brain CT was reviewed. The overall survival and intracranial progression-free survival were compared in each group. Results: The median follow-up period was 5 months (range, 2∼19 months) in the SRS group and 6 months (range, 4∼23 months) in the WBRT group. The mean number of metastatic lesions in the SRS and WBRT groups was 6 and 5, respectively. The intracranial progression-free survival and overall survival in the SRS group was 5.1 and 5.6 months, respectively, in comparison to 6.1 and 7.2 months, respectively, in the WBRT group. Conclusion: SRS was less effective than WBRT in the treatment of patients with >4 metastases to the brain.

Influence of intravenous contrast agent on dose calculations of intensity modulated radiation therapy plans for head and neck cancer

Choi, Youngmin,Kim, Jeung-Kee,Lee, Hyung-Sik,Hur, Won-Joo,Hong, Young-Seoub,Park, Sungkwang,Ahn, Kijung,Cho, Heunglae Elsevier 2006 Radiotherapy and oncology Vol.81 No.2

<P><B>Abstract</B></P><P><B>Background and purpose</B></P><P>To evaluate the effect of an intravenous contrast agent (CA) on dose calculations and its clinical significance in intensity modulated radiation therapy (IMRT) plans for head and neck cancer.</P><P><B>Materials and methods</B></P><P>Fifteen patients with head and neck cancer and involved neck nodes were enrolled. Each patient took two sets of computerized tomography (CT) in the same position before and after intravenous CA injections. Target volumes and organs at risk (OAR) were contoured on the enhanced CT, and then an IMRT plan of nine equiangular beams with a 6MV X-ray was created. After the fusion of non-enhanced and enhanced CTs, the contours and the IMRT plan created from the enhanced CT were copied and placed to the non-enhanced CT. Doses were calculated again from the non-enhanced CT by the same IMRT plan. The radiation doses calculated from the two sets of CTs were compared with regard to planning target volumes (PTV) and the three OARs, both parotid glands and the spinal cord, by Wilcoxon’s signed rank test.</P><P><B>Results</B></P><P>The doses (maximum, mean, and the dose of 95% of PTV received (<I>D</I><SUB>95%</SUB>)) of PTV70 and PTV59.4 calculated from the enhanced CTs were lower than those from the non-enhanced CTs (<I>p</I><0.05), but the dose differences were less than 1% compared to the doses calculated from the enhanced CTs. The doses of PTV50.4, parotid glands, and spinal cord were not significantly different between the non-enhanced and enhanced CTs.</P><P><B>Conclusions</B></P><P>The difference between the doses calculated from the CTs with and without CA enhancement was tolerably small, therefore using intravenous CA could be recommended for the planning CT of head and neck IMRT.</P>