내용기반 이미지 검색 시스템에 대한 고찰과 설계 요건에 대한 연구

서재현,서상환,김흥식 인제대학교기초과학연구소 1998 자연과학 Vol.2 No.-

멀티미디어 데이터베이스의 내용기반 검색은 색인 기술을 요구한다. 전통적인 데이터베이스와는 달리 데이터 항목은 기본이 되는 데이터 타입들의 속성의 집합으로 나타내어지는데, 멀티미디어 데이터베이스에 있는 멀티미디어 객체는 특징들의 수집에 의해 표현되고, 객체 내용의 유사성은 문맥과 참조의 프레임에 의존하며, 객체의 특징은 다중양식 특징 측정에 의해 특성화된다. 내용기반 이미지 검색을 단계별로 3가지 큰 작업으로 나누어 보면 해당 이미지를 가장 정확하게 특징들을 추출하는 단계와 그 추출된 특징을 효과적이고 능률적으로 저장, 검색을 지원하는 단계와 다시 이미지의 유사성을 검출해 내는 단계로 요약된다. 본 논문에서는 기존에 연구된 이미지 특징 추출들을 연구 분석하고 이미지 내용 기반 검색에 적합한 다양한 특징 추출과 유사도 검색에서의 문제점과 이에 대한 적합한 설계요건에 대해 제시한다. Content-based retrieval of multimedia database calls for content-based indexing techniques. Different from conventional databases, where data items are represented by a set of attributes of elementary data types, multimedia objects in multimedia databases are represented by a collection of features; similarity of object contents depends on context ad frame of reference; and features of objects are characterized by multimodal feature measures. Try to divide content-based images retrieval systems into three large operation, it is consist of the following three phases; extracting features that can represent images the most exactly, storing the extracted features effectively and efficiently and support retrieval, detect similarity of images. In this paper we first investigated and analyse the existing image feature extraction methods and various features extraction that adequate for content-based image retrieval and problem of similarity retrieval, we also present design of suitable demand.

화학환원법을 이용한 Ag 나노분말의 합성

서원식,김태환,성재석,송기창 한국화학공학회 2004 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.42 No.1

화학환원법을 이용하여 AgNO_(3) 수용액에 환원제를 첨가시키는 방법으로 Ag분말을 제조하였으며, 이 과정 중 환원제의 종류 변화(N_(2)H_(4), NaBH_(4))가 얻어진 분말의 특성 변화에 미치는 영향을 살펴보았다. 또한 분말합성 과정 중 계면활성제(Tween20)를 수용액에 첨가하여 계면활성제가 분말의 특성에 미치는 영향도 살펴보았다. 제조된 분말의 SEM 측정결과 환원제로 sodium borohydride(NaBH_(4))를 사용하면서 제조된 Ag 분말의 크기는 약 0.3㎛인 반면 hydrazine(N_(2)H_(4))을 사용하여 제조된 분말의 크기는 약 1㎛로 sodium borohydride를 사용해 제조한 분말의 크기가 더 작고 고른 크기 분포를 보였다. 또 환원제로써 hydrazine을 사용시 계면활성제를 첨가하여 제조된 Ag 나노분말의 크기는 50nm정도로 계면활성제를 첨가하지 않고 제조된 분말보다(1㎛) 입자의 크기가 더 작고 균일한 입도 분포를 나타내었다. Silver powders were prepared by chemical reduction method using reductants in AgNO_(3) aqueous solution. The effect of the type of reductants(N_(2)H_(4), NaBH_(4)) was investigated on the properties of the obtained powders. In addition, the effect of the addition of asurfactant(Tween 20) during particle synthesis was studied. The Ag powders prepared using the sodium borohydride as a reductant were found to be 0.3㎛ in particle diameter, while those using the hydrazine showed 1㎛ in particle diameter. The mean particle size of Ag nanopowders, prepared by the addition of Tween 20 as a surfactant, was 50㎚, which is smaller than 1㎛ powders formed without the surfactant.

특이한 악관절 강직증 : 진성 악관절 강직증과 상악골과 하악골 사이의 골성 유합

서재훈,조세인,여환호,이기혁,김영균 大韓顎顔面成形再建外科學會 1995 Maxillofacial Plastic Reconstructive Surgery Vol.17 No.2

TMJ ankylosis is classified with true and false type. A true ankylosis is defined as any condition that produces fibrous or bony adhesions between the articular surfaces of the temporomandibular joint. The main causes of true ankylosis are trauma or infection. A false ankylosis results from pathologic conditions outside the joint that limit mobility of the mandible such as myogenic disorders, coronoid impingement or rare direct bony fusion between maxilla and mandible. The treatment of choice of TMJ ankylosis is surgical intervention. We experienced the male patient with complete mouth opening limitation since 45 years before. This patient has true TMJ ankylosis and rare bony synostosis between maxilla and mandible in the right posterior region. We performed surgical intervention and had a favorable result.

악성종양과 감별이 어려웠던 악안면 영역의 감염질환에 대한 치험례

서재훈,김영균,여환호 大韓顎顔面成形再建外科學會 1995 Maxillofacial Plastic Reconstructive Surgery Vol.17 No.3

It is very difficult to differentiate the malignant tumor from the maxillofacial infections that have unclear cause, severe indurated swelling, pain and nonresponsiveness to antibioitic treatment and incision and drainage. Incisional biopsy, CT, and MRI examination may not distinguish between infection and a malignant tumors. And then, the clinicians can make a mistake that they perform a unnecessary radical surgery because of inaccurate diagnosis. We present three case reports of maxillofacial infectious disease with diagnosis process, treatment and differential diagnosis. The infectious disease were not resolved with antibiotic and surgical drainage. The progression of clinical sign and radiographic, indings of these disease were masqueraded as malignant tumors.

연합대학으로의 대학 체제 변화에 관한 연구

서재천,서강식,조붕환,지옥화,장원순 공주교육대학교 2010 公州敎大論叢 Vol.47 No.1

본 연구는 교육과학기술부의 경쟁력있는 국립대학을 만들고자 시행하고 있는 여러 정책 중 연합대학으로의 체제 변화 권유에 대한 장단점과 이해득실을 냉철하게 객관적으로 고찰해 보고자 수행되었다. 연구의 수행방법은 연합대학 체제의 추진이나 독자생존의 길 등 의사결정에 참고자료가 될 수 있도록 일본과 미국 등 외국의 연합대학 사례를 중심으로 수집 가능한 자료를 수집하여 고찰한 후 연합대학 체제 추진이나 독자생존의 장단점을 알아보았다. 본 연구의 결과는 여러 가지 외적인 상황 속에서 우리 대학이 독자적으로 생존하는 것이 가능한가, 또는 결국에는 독자적 생존의 대안으로 연합 내지는 통합의 길을 선택할 수밖에 없는가 하는 것은 그 누구도 쉽게 예단하기 어렵다는 것이다. 그러나 대학 구성원들이 미래를 선택하지 않는다 하더라도 외적인 요인에 의해 미래가 결정될 여지가 있으므로 지금부터라도 대학의 미래에 관한 공동의 지혜를 모아야 할 것으로 생각한다. 함께 머리를 맞대고 허심탄회하게 서로의 의견을 존중하며 서로에 대한 불신을 털어버리고 진정 대학의 미래를 위한 바른 선택이 무엇인가에 관한 논의와 연구가 꾸준하게 지속되어야 할 것으로 판단된다. This study was carried out in order to try to consider objectively merits and demerits regarding a system change invitation toward the Union University System and understanding gains and losses during a lot of policies to make a national college that there was competitiveness of Ministry of Education, Science and Technology of education. The results of this study is that no one is easy to predict, that it does as alternatives of an independent survival or select a street of integration and the Union University System in various external situations, finally. However, the University members does not select the future even if in various external factor because there is no doubt that the future will be decided from now on any University in the future regarding collaborative wisdom of the university, We thought it was going to do. Head with open-minded to respect each other's opinions and distrust each other confide you discard the truly University for the future, select the right to discuss and research can be sustained.

혼합운동이 중년여성들의 신체구성 및 혈액성분에 미치는 영향

서영환,임재용,임달식 朝鮮大學校 스포츠科學硏究所 2007 스포츠科學硏究 Vol.18 No.-

This research of got result following conclusion that observe that some change appears in body composition and blood component etc, when executed muscular power exercise between 8 weeks and composition exercise of jogging to forty to fifty years women who this research does not take part in regular exercise

캔터키 블루그래스에 의한 잔디 조성 기술 개발

이재필,조용인,서한용,이상재,김태준,한인송,김두환 建國大學校附設農業資源開發硏究所 2001 農資源開發論集 Vol.23 No.-

Seed sowing is the major method for the establishment of cool-season grasses at the soccer fields, golf courses, etc. Germination speed of kentucky bluegrass(Poa prantensis L.: KB) is much slower than the other cool-season grasses. This study was conducted to solve the problems at the early stage of establishment with KB. The best priming conditions of KB, drying method after soaking in the water, and covering materials will be selected. To reduce irrigation frequency and quantity for seed germination, seeds of KB were exposed to the different soaking temperature(4, 20, 25, 30℃). soaking durations(3, 6, 10, 13, 19, 23 days), storage periods(3, 6, 9 days), storage humidities(30, 50, 100%), shading rate(0, 50, 100%), drying methods(dry in the air, heating, mix soaked seed with profile=1:2), and covering materials(70% shade net, fiber net). The optimum soaking temperature and duration for the seed priming of KB were 20℃ and 10 days, respectively. The optimum storage period and humidity were 3 days and 100%, respectively, Under 50% shading, germination rate was the highest. In drying method after soaking, mixture of seeds and profile(1:2) was optimum for sowing. Using the thin fiber net as covering material after sowing was good for not moving seeds and improved germination speed and rate.

신경회로망을 이용한 이면비드 폭 예측에 관한 연구

정재원,김일수,박창언,김학형,서주환,김인주,심지연 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-

The development of robotic welding process is a very complex assignment because the system is affected by a number of process parameters which are very difficult to determine or predict in practice. The full automation welding has not yet been achieved partly because the mathematical model for the process parameters of a given welding task is not fully understood and quantified. Several mathematical models to control welding quality, Productivity, micro structure and weld properties in arc welding processed have been studied. However, it is not an easy task to apply them to the various practical situations because the relationship between the process parameters and the bead geometry is non-linear and also they are usually dependent on specific experimental result. Practically, it is difficult, but important to know how to establish a mathematical model that can predict the result of the actual welding process and how to select the optimum welding condition under a certain constraint. In this paper, an attempt has been made to develop an neural network model to predict the back-bead width as a function of key process parameters in the GMA (Gas Metal Arc) welding and to compare the developed models with the experimental results

인천지역 강하분진의 발생특성에 관한 연구

박경환,서광석,민달기,장재선,김종규 京畿專門大學 1994 京畿專門大學 論文集 Vol.- No.22

Electron Cyclotron Resonance O_2 Plasma에서 증착한 규소 산화 박막의 특성

안명환,서문석,장재선,서성모,이기방,윤창주,이형재,남기석,최규현,손춘배,김용섭,강석희 全北大學校 基礎科學硏究所 1994 基礎科學 Vol.17 No.-

규소 산화막을 ECR-CVD(electron cyclotron resonance-chemical vapor deposition) 증착방법으로 5인치 기판위에 상온에서 증착하고, 증착공정조건인 증착율, 기판온도, 마이크로파의 세기변화 및 플라즈마 혼합기체의 비에 따른 규소 산화막의 특성을 조사하였다. 또한 산화막의 구조적인 특성을 비교하기 위해 FTIR을 이용하여 ECR-CVD 증착한 산화막, RPE-CVD(remote plasma enhanced-CVD) 증착한 산화막 및 열 산화막의 stretching frequency를 측정하였다. 측정된 결과 ECR-CVD로 증착된 산화막이 구조적인 면에서 열 산화막과 거의 같음을 보였다. ECR-CVD로 증착된 산화막의 전기적인 특성을 전류-전압 및 축전-전압 측정에의하여 분석하였다. 축전된 산화막의 전기적인 특성은 산화막의 전하 밀도는 1×10 exp (11)/㎠이였고, 평균 절연 파괴 전압은 약 6 MV/㎝이다. We have grown thin films of SiO_2 at room temperature by using an ECR-CVD system and have investigated the changes in the properties of the deposited films with changes in the processing conditions such as the deposition rate, the substrate temperature, the microwave power and the plasma gas mixing ratio. We also measured the stretching frequency of three kinds of oxides, and ECR-CVD-grown oxide, a PECVD-grown oxide, and a thermally grown oxide, using FTIR analysis to compare their structural properties. The result shows that the structural properties of the ECR-grown oxide are similar to those of the thermally grown oxide. Additionally, the electrical properties of the ECR-grown oxide were investigated by using current-voltage and capacitance-voltage measurements. These electrical results indicate that the oxide charge density and the average breakdown voltage are 1×10 exp (11) ㎝^-2 and 6 MV/㎝, respectively.