졸-겔법에 의해 제조한 K_0.5Bi_0.5TiO₃ 막과 압전발전기의 특성

이영호,박상식,Lee, Young-Ho,Park, Sang-Shik 한국재료학회 2021 한국재료학회지 Vol.31 No.11

K_0.5Bi_0.5TiO₃ (KBT) thin films were prepared by sol-gel processing for future use in piezoelectric generators. It is believed that the annealing temperature of films plays an important role in the output performance of piezoelectric generators. KBT films prepared on Ni substrates were annealed at 500 ~ 700 ℃. Tetragonal KBT films were formed after annealing process. As the annealing temperature increased, the grain size of KBT films increased. KBT thin films show piezoelectric constant (d₃₃) from 23 to 41 pC/N. The increase of grain size in KBT films brought about output voltage and current in the KBT generators. Also, the increase in the displacement of specimens during bending test resulted in increases in output voltage and current. Although KBT generators showed lower output power than those of generators prepared using NBT films, as reported previously, the KBT films prepared by sol-gel method show applicability as piezoelectric thin films for lead-free nano-generators, along with NBT films.

인구구조 변화에 따른 대학의 미래

이영호,Lee, Yeong-Ho 한국대학교육협의회 2004 大學敎育 Vol.131 No.-

대학의 위기는 대학진학 인구의 감소가 가져온 위기 외에도 교육기능 뿐만 아니라 새로운 지식창출을 통한 국가 경쟁력 강화의 견인차가 되어 줄 것을 요구받고 있으며, 대학인들의 적극적인 사회봉사와 참여를 통한 건전한 시민사회 형성에도 그 책임을 다해줄 것을 요구받고 있다.

Broadband Convergence Network 가입자 망 설계 시스템 연구

이영호,정진모,김영진,이순석,박노익,강국창,Lee, Young-Ho,Jung, Jin-Mo,Kim, Young-Jin,Lee, Sun-Suk,Park, No-Ik,kang, Kuk-Chang 한국경영과학회 2006 經營 科學 Vol.23 No.2

In this paper, we consider a network optimization problem arising from the deployment of BcN access network. BcN convergence services requires that access networks satisfy QoS meausres. BcN services have two types of traffics : stream traffic and elastic traffic. Stream traffic uses blocking probability as a QoS measure, while elastic traffic uses delay factor as a QoS measure. Incorporating the QoS requirements, we formulate the problem as a nonlinear mixed-integer Programming model. The Proposed model seeks to find a minimum cost dimensioning solution, while satisfying the QoS requirement. We propose two local search heuristic algorithms for solving the problem, and develop a network design system that implements the developed heuristic algorithms. We demonstrate the computational efficacy of the proposed algorithm by solving a realistic network design problem.

무수축 모르타르 충진형 슬리브 개발

이영호,송재준,조재영,김도학,Lee. Young-Ho,Song. Jae-Joon,Cho. Jae-Young,Kim. Do-Hak 한국방재학회 2011 한국방재학회논문집 Vol.11 No.2

본 연구의 목적은 공기 단축과 초기 공사비를 절감하기 위해 PC 긴장재를 사용하지 않고, 슬리브와 일반 철근만으로 구성된 경제적이면서 시공성이 우수한 프리캐스트 교각 공법 개발에 있다. 이를 위해 본 연구에서는 신형식 철근이음 장치인 그라우팅형(形) 슬리브(Splice sleeve, 이하 슬리브)를 제안하고 최적의 슬리브를 개발하기 위하여 슬리브 길이, 철근직경, 양생방법 등을 변수로 하여 유한요소해석 및 인장실험을 수행하였다. 슬리브의 유한요소해석을 통하여 최적의 형상을 도출하였으며, 인장 성능 검토 결과, 철근의 인발에 의한 파괴는 발생하지 않았으며, 철근의 인장 파괴 혹은 슬리브의 기계적 결함에 의한 볼트 파단만이 관찰되었다. 제안된 슬리브는 우수한 인장성능을 갖고 있음을 확인하였으며 프리캐스트 교각에 무리 없이 적용할 수 있음을 검증하였다. This study aims to develop an economical precast hollow concrete column with high constructability which consists of only splice sleeve and general reinforcing bar without using PC tendons in order to reduce the construction period and cost. With this purpose, this study performed the finite element analysis and tension test by using some variables such as length of sleeve, diameter of rebar and curing method for suggesting a grouting type splice sleeve which is a new type joint rebar and developing an optimized splice sleeve. As a result, the analysis on the tension performance of splice sleeve did not show any destruction caused by pull-out in reinforcing bar but it only occurred destruction of tension bar or bolt shear rupture from the mechanical defect of sleeve. Therefore, the experiment showed high performance in tension of the suggested splice sleeve and verified the application of precast hollow concrete column.

비외상성 피질하 뇌혈관 질환 환자에서 인지기능, 정신행동 증상 및 일상 생활 기능간의 상관에 대한 연구

이영호,박영수,최홍,최영희,고대관,정영조,박병관,김수지,정숙희,고병희,송일병,박건우,이대희,Lee, Young-Ho,Park, Young-Soo,Choi, Hong,Choi, Young-Hee,Ko, Dae-Kwan,Chung, Young-Cho,Park, Byoung-Kwan,Kim, Soo-Ji,Chung, Suk-Hai,Ko, Byoung-Hee,So 한국정신신체의학회 1996 정신신체의학 Vol.4 No.2

Objective : This study was tried to investigate the specific relationships among cognitve function, neurbehavioral symptoms, and daily living functions, as well as provide the guidline of more proper clinical approches for patients with subcortical cerebrovascular disease. Objects and Methods Subjects were 85 patients whose diagnosis was confirmed by brain CT or MRI and controls were 195 normal persons matched by educational level with the subjects. The cognitive functions were evaluated by BNA(Benton neuropsychiatric assessment), subjective neurobehavioral symptoms by SCL-90-R(Sympton Check List-90-Revised), objective neurobehavioral symptoms by NRS(Neurobehavioral Rating Scale), and daily living function symptoms by NRS(Neurobehavioral Rating Scale), and daily living function by GERRI(Geriatric Evaluation by Relative's Rating Instrument) and IADL(Instrumental Activities of Daily Living Scale). Results: 1) Subjects showed significantly lower cognitive functions than controls in all tests of BNA except Lt-Rt Orientation Test(p=0.09) and facial Recognition Test(p=0.186). 2) In subjective neurobehavioral symptoms, subjects showed significantly lower scores in all symptoms except anxiety(p=0.059), hostility(p=0.159), and phobic anxiety(p=0.849). But in objects neurobehavioral symptoms, subjects showed significantly higher in scores in psychoticism (p=0.000) and neuroticism(p=0.025) of NRS. 3) The score of social functioning of GERRI(p=0.000) and that of IADL(p=0.000) were significantly higher in subjects than in controls. 4) for correlation between cognitive and daily living functions, there were significant correlations between the scores of all items on BNA and the score of cognitive or social function of GERRI and the socre of MDL in corntrols, whereas in subjects, there were significant correlations only between the scores of BNA and the score of IADL. 5) for correlation between neuroehavioral symptoms and daily living functions, there were significant correlatons between the socre of subjective neurobehavioral symptoms and the scores of all subscales of GERRI and the score of MDL in controls. On the contrary, in subjects, there were significant correlations between the score of social function of GERRI and the score of objective neurobehavioral symptoms such as psychoticism, agitiation-hostility, and decrease d motivation-emotional withdrawl. Conclusion : Above results suggest that disturbances in specific function of brain may play a role as a predictor of impairments with specific daily living functions and also suggest that specific correlations among various functions may be useful as clinical parameters for setting of the treatment goal and for assessing the ongoing process in the treatment and rehavilitation of the patients with subcortical cerebrovascular disease.

RFM 모델 기반의 병원고객 세분화 전략

이영호,강운구,황희정,Lee, Young-Ho,Kang, Un-Gu,Hwang, Hee-Jung 한국정보과학회 2005 정보과학회논문지 : 기술교육 Vol.2 No.1

의료시장개방등 보건의료 환경의 변화에 대응하기 위해서 병원도 기업과 같이 병원의 경쟁력이 고객중심의 의료를 통한 고객관계관리를 도입해야 하는 시대가 도래 하였다. 이를 위해 병원 고객의 성격 및 정확한 분류를 통해 좀더 체계적인 고객관리 방법이 요구되고 있다. 본 논문에서는 인천에 위치한 1300병상 이상의 종합병원고객을 대상으로 데이타 구간화를 적용한 RFM(Recency Frequency Monetary)모델을 도입하여 고객등급화를 수행하고, 데이타마이닝 사후분석를 실시하여 효율적인 고객관리 방법을 찾아본다. In order to cooperate today's healthcare environmental changes such as healthcare market opening and increase their competitiveness, Hospitals should perform customer based medical service and bring Customer Relationship Management to their system like other industries and enterprises. Therefore they need to reorganize customer management by analysis and classification of customers. This paper will suggest effective customer management strategies by the performing customer segmentation through RFM model which is applied by data tinning and analysis of data mining. Its study sample is from the general hospital with more than 1300beds in Incheon.

엔터프라이즈 아키텍처 도입요인에 관한 실증적 연구 : Technology-Organization-Environment 프레임워크를 중심으로

이영호,채명신,Lee, Young-Ho,Chae, Myung-Sin 한국경영과학회 2006 經營 科學 Vol.23 No.2

Interest in EA has been Increasing recently, however, with the coming into effect from July 2006 of the 'Information Technology Architecture Act' which requires the public sector to adopt EA. Until now, the study of EA has been focused on concepts and methodologies for the adoption of EA. The fundamental issue, however, the study on the factors affecting the adoption of EA, has rarely been explored. This thesis therefore surveyed which factors have affected the adoption of EA. The analysis found that the adoption of EA was affected by the external environmental characteristics such as rules or regulations and the level of competition in the Industry concerned, and by the organization's information technology level. However, technological aspects such as perceived usefulness or perceived ease of use - traditionally considered as critical factors in adopting information technology - were found to be less influential. These results show that in Korea we still do not regard EA as a method of optimizing the IT resources of a company. In order for EA to be widely adopted, therefore, we should Put primary emphasis on efforts to properly appreciate its technological aspects, such as its technological usefulness or convenience.

음절을 기반으로한 한국어 음성인식

이영호,정홍,Lee, Young-Ho,Jeong, Hong 대한전자공학회 1994 전자공학회논문지-B Vol.b31 No.1

For the conventional systme based on word, it is very difficult to enlarge the number of vocabulary. To cope with this problem, we must use more fundamental units of speech. For example, syllables and phonemes are such units, Korean speech consists of initial consonants, middle vowels and final consonants and has characteristic that we can obtain syllables from speech easily. In this paper, we show a speech recognition system with the advantage of the syllable characteristics peculiar to the Korean speech. The algorithm of recognition system is the Time Delay Neural Network. To recognize many recognition units, system consists of initial consonants, middle vowels, and final consonants recognition neural network. At first, our system recognizes initial consonants, middle vowels and final consonants. Then using this results, system recognizes isolated words. Through experiments, we got 85.12% recognition rate for 2735 data of initial consonants, 86.95% recognition rate for 3110 data of middle vowels, and 90.58% recognition rate for 1615 data of final consonants. And we got 71.2% recognition rate for 250 data of isolated words.

수처리기계분야 연구동향

이영호,Lee, Young-Ho 한국유체기계학회 2006 한국유체기계학회 논문집 Vol.9 No.1

고령화 사회 환경 변화에 대응하는 정보통신 산업 비즈니스 모델 설계

이영호,김영욱,김영진,김혜원,이정민,Lee, Young-Ho,Kim, Young-Wook,Kim, Young-Jin,Kim, Hye-Won,Lee, Jeong-Min 한국경영과학회 2006 經營 科學 Vol.23 No.3

In this paper, we develop the business model of telecommunication company that facilitates to explore new business opportunities on aging society. Considering the trend of aging society, we analyze the market drivers of senior market. Analyzing market dynamics and value chain, we design a set of business models for telecommunication company. In addition, we describe the evolution path of the proposed business model in terms of technology development and market. Finally, we develop a framework for evaluating the effectiveness of the business model.