웨이블렛 계수의 효율적인 전송에 따른 가변제로트리코더의 성능개선

주상현,신재호,Joo, Sang-Hyun,Shin, Jae-Ho 대한전자공학회 1999 電子工學會論文誌, C Vol.c36 No.9

Shaprio가 발표한 EZW에서는 한 대역의 부(父)계수가 유사방향의 인접 고주파대역에 4개의 자(子)계수들과 부자관계를 구성하는 고정트리를 기반으로 한다. 이러한 고정트리는 대역간의 계층적 상관관계를 고찰하는데는 적합할 수 있으나, 4개의 계수가 하나의 $2{\times}2$의 블록단위로 처리되기 때문에 대역내 인접계수들간에 존재하는 공간적 상관관계를 고찰하기에는 부적합하다. 이러한 대역간의 계층적 상관관계와 대역내의 공간적 상관관계의 동시에 고찰하기 위하여 가변트리가 제안되었다. 그러나 가변트리는 웨이블렛 계수들을 표현하는데 있어, 고정트리에 비해 많은 심볼들을 필요로 한다. 반면 심볼당 정보량(entropy)이 낮아지는 결과를 가져오기 때문에 고정트리에 비해 압축성능을 향상시킨다. 본 논문에서는 가변트리로 인한 심볼 수의 증가를 억제하는 두 가지 기법ㅂ을 제안한다. 첫째, 무효계수에 대한 불필요한 스캔을 억제하기 위하여 각각의 유효 부계수에 대하여 유효 자계수의 소유여부를 미리 알려주는 1비트의 탐사비트(probing bit)를 발생시킨다. 둘째, 대역에 따라 필요로 하는 심볼 알파벳이 다르다는데 근거하여 대역별 특성을 고려한 심볼세트를 새로이 정의한다. 이러한 두 가지의 기법에 의하여 발생하는 심볼의 수는 상당히 줄어들게 되고, 출력된 심볼들은 추가 엔트로피코딩을 하지 않고 그대로 전송되더라도 비교적 좋은 압축결과를 가져올 수 있다. 가변트리와 심볼수의 억제기법에 의하여 변형된 EZW 부호화 방식은 적응산술부호화기를 포함한 모드와 포함하지 않은 모드의 두 가지 형태에서 제안된다. 본 논문에서 제안하는 부호화방식은 가변트리와 심볼발생억제 방식을 EZW에 적용시켜 성능향상을 꾀하며, 적용되어진 EZW와의 성능비교를 통하여 이러한 제안방식의 유효성을 점검해 본다. EZW proposed by Shapiro is based on a zerotree constructed in a way that a parent coefficient in a subband is related to four child coefficients in the next finer subband of similar orientation. This fixed treeing based on 1-to-4 parent-child is suitable to exploti hierachical correlations among subbands but not to exploit spatial correlations within a subband. A new treeing by Joo, et al. is suggested to simulatneously exploit those two correlatins by extending parent-child relationship in a flexible way. The flexible treeing leads to increasing the number of symbols and lowering entorpy comparing to the fixed treeing, and therefore a better compression can be resulted. In this paper, we suggest two techniques to suppress the increasing of symbols. First, a probing bit is generated to avoid redundant scan for insignivicant coefficients. Second, since all subbands do not always require the same kind of symbol-set, produced symbols are re-symbolized into binary codes according to a pre-defined procedure. Owing to those techniques, all symbols are generated as binary codes. The binary symbols can be entropy-coded by an adaptive arithmetic coding. Moerover, the binary symbol stream can give comparatively good performances without help of additional entropy coding. Our proposed coding scheme is suggested in two modes: binary coding mode and arithmetic coding mode. We evaluate the effectivenessof our modifications by comparing with the original EZW.

효율적 조경공사 프로젝트 수행을 위한 과업범위설정관련 기초 연구

주상현,이재근,Joo, Sang-Hyun,Lee, Jae-Keun 한국조경학회 2008 韓國造景學會誌 Vol.36 No.3

토목이나 건축공사와는 달리 조경공사 프로젝트는 그 공정상의 특수성과 규모의 영세성으로 인해 공정관리나 프로젝트관리에 대한 노력이 부족한 실정이다. 이러한 상황 하에서 건축이나 토목 프로젝트 관리 차원에서 많은 연구가 진행되고 있는 과업범위설정에 대한 개념을 조경프로젝트에 적용해 보는 것은 두 가지 측면에서 큰 유익이 있을 것으로 판단된다. 첫째, 파업범위설정은 적용을 위한 추가적인 비용이나 시간적 투자 없이 간단한 절차를 통해 시행해 볼 수 있다는 것이고 둘째, 과업범위설정과 관련된 절차를 통해 얻어지는 결과는 매우 실질적이라는 점이다. 본 연구는 국내 조경공사 프로젝트 수행 시 수반되는 과업범위설정 과정에 대한 조사를 실시하였고 또한, 효율적인 조경프로젝트 수행을 위한 과업범위설정을 돕기 위하여 다양한 방법을 통해 조경공사 프로젝트의 성공요인을 도출하였다. 문헌 연구와 설계사례 분석 그리고 전문가 인터뷰와 설문조사를 통하여 3개 분야 8개 부분의 50개 요소를 조경프로젝트 성공요소로 도출하게 되었다. 도출된 요소들은 조경공사 프로젝트 참가자들 간의 과업범위설정 수준을 향상시키며 효율적인 조경 공사 프로젝트 수행에 기여할 것으로 기대된다. Differing from civil engineering and construction, landscape architecture projects are far from efforts in operation and project management. Under the circumstances, it is worthwhile to adopt scope definition from project management for construction and civil engineering in some respects. First, scope definition is able to be conducted through a simple procedure without additional investment in capital and time. Second, the output produced by scope definition is very substantial. The research scrutinized scope definition procedures accompanied by landscape architecture project execution and derived various methods in order to help scope definition for efficient landscape architecture projects. Based on the literature review, a design case study, and an exert interview, the project success elements were developed consisting of 3 sections, 8 categories and 50 elements, grounded on the theoretical base of PDRI. The elements are expected to pave a way to an adequate level of scope definition among participants of landscape architecture projects and contribute in efficient project execution.

페놀수지 및 에틸렌 글리콜을 첨가한 유리질 카본 코팅층의 물성 제어

주상현,주영준,이혁준,심영진,박동진,조광연,Joo, Sang Hyun,Joo, Young Jun,Lee, Hyuk Jun,Sim, Young Jin,Park, Dong Jin,Cho, Kwang Youn 한국결정성장학회 2022 한국결정성장학회지 Vol.32 No.3

In this study, glassy carbon coating was performed on the graphite using a phenolic resin and a curing agent was mixed with ethylene glycol as an additive to form the uniform surface. The phenolic resin was dried and cured under the environments of hot air, then converted into a glassy carbon layer by pyrolysis at 500~1,500℃. FTIR, XRD, SEM analysis, and density/porosity/contact angle measurement were performed for characterization of glassy carbon. The pyrolysis temperature for high-quality glassy carbon was optimized to be about 1,000℃. As the content of the additive increased, the effect of reducing surface defects on the coated surface, reduction of porosity, increase of contact angle, and increase of density were investigated in this study. The method of forming a glassy carbon coating layer through an additive is expected to be applicable to graphite coating and other fields.

실시간 주행성 분석에 기반한 6×6 스키드 차량의 야지 고속 자율주행 방법

주상현,이지홍,Joo, Sang-Hyun,Lee, Ji-Hong 제어로봇시스템학회 2012 제어·로봇·시스템학회 논문지 Vol.18 No.3

Unmanned ground vehicles have important military, reconnaissance, and materials handling application. Many of these applications require the UGVs to move at high speeds through uneven, natural terrain with various compositions and physical parameters. This paper presents a framework for high speed autonomous navigation based on the integrated real time traversability. Specifically, the proposed system performs real-time dynamic simulation and calculate maximum traversing velocity guaranteeing safe motion over rough terrain. The architecture of autonomous navigation is firstly presented for high-speed autonomous navigation. Then, the integrated real time traversability, which is composed of initial velocity profiling step, dynamic analysis step, road classification step and stable velocity profiling step, is introduced. Experimental results are presented that demonstrate the method for a $6{\times}6$ autonomous vehicle moving on flat terrain with bump.

열평형법을 이용한 교육시설의 공조부하 시뮬레이션

주상현(Sang Hyun Joo),김정엽(Jung Yup Kim),신현준(Hyun Jun Shin) 대한설비공학회 2010 대한설비공학회 학술발표대회논문집 Vol.2010 No.6

The purpose of this study was to compare the RTS law of simple calculation method with Heat Balance Method and dynamic simulation program ‘EnergyPlus 4.0’ for air conditioning load calculation of the building. This study was carry out the modeling of dynamic simulation in the same condition of Nonresidential Cooling and Heating Load Calculations of ASHRAE Standard to suggest calculation result of RTS. As a result, Calculation result of ‘EnergyPlus 4.0’ Reliability was obtained through comparative analysis with maximum value. Based on the results of analysis were loads of educational Structure.

루푸스 장염 치료 중 발생한 소장 천공을 동반한 허헐성 장염 1예

주상현 ( Sang Hyun Joo ),이재명 ( Jae Myung Lee ),박진균 ( Jin Kyun Park ),이은영 ( Eun Young Lee ),이은봉 ( Eun Bong Lee ),송영욱 ( Yeong Wook Song ) 대한류마티스학회 2015 대한류마티스학회지 Vol.22 No.6

Development of ischemic enteritis is rare in patients with systemic lupus erythematosus (SLE). We report on a case of ischemic enteritis with small bowel perforation in a 54-year-old female patient with SLE. She was diagnosed as SLE at 20 years old. Nine months ago, she developed periumbilical pain and was diagnosed with lupus enteritis. She was treated with prednisolone (0.5 mg/d), which was tapered gradually over 6 weeks. Prednisolone was maintained at 12.5 mg once a day. A similar periumbilical pain episode occurred again 7 months ago. Four weeks ago, she visited the emergency room due to diffuse abdominal pain, and abdominal computed tomography showed small bowel obstruction. Gastrointestinal manifestations improved after conservative management. She visited again due to severe abdominal pain for 2 days. She had panperitonitis due to a small bowel perforation and underwent an emergency laparotomy. The surgical specimen revealed ischemic enteritis involving whole bowel wall thickness with perforation. We report on a case of ischemic enteritis with small bowel perforation in a SLE patient diagnosed as lupus enteritis with literature review. (J Rheum Dis 2015;22:378-381)

AOTC를 이용한 Jlet 실행 환경의 설계 및 구현

주상현(Sang-Hyun Joo),조기연(Ki-Yeon Joe),정민수(Min-Soo Jung) 한국멀티미디어학회 2004 한국멀티미디어학회 학술발표논문집 Vol.2004 No.2

유전알고리즘을 이용한 리니어모터의 설계변수 최적화에 관한 연구

주상현(Sang Hyun Joo),정재한(Jae Han Jung),이상룡(Sang Ryong Lee) Korean Society for Precision Engineering 2002 한국정밀공학회지 Vol.19 No.5

신경망을 이용한 영상의 벡터 양자화

주상현(Sang-Hyun Joo),원치선(Chee-Sun Won),신재호(Jae-Ho Shin) 대한전자공학회 1993 대한전자공학회 학술대회 Vol.1993 No.7

곡선주행 실시간 주행성 분석을 위한 스키드 차량의 동역학 모델링

주상현(Sang Hyun Joo),이지홍(Jihong Lee) 제어로봇시스템학회 2012 제어·로봇·시스템학회 논문지 Vol.18 No.4

Real-Time Traversability should be analyzed from the equiped sensors" navigation. However, it is difficult to find out such traversability that considers the especially in case of skid type vehicle. The traversability based on real time dynamic analysis was proposed to solve such problem but in navigation with strait driving path. To adapt the method into the navigation with curved driving path, a path following controller should be incorporated into the dynamic model even though it cause the real time problem. In this paper, a dynamic model is proposed to solve the real time problem in the traversability analysis based on real time dynamic simulation. The dynamic model contains the control dummy which is connected to the vehicle body with a universal joint to follow the curved path without controller. Simulation and experimental results on 6x6 articulated unmanned ground vehicle demonstrate the method"s effectiveness and applicability into the traversability analysis on terrain with bumps.