• 제목, 요약, 키워드: Exploration

검색결과 4,601건 처리시간 0.065초

IPTV 제어를 위한 대화관리시스템 설계 (Dialogue Management System for IPTV)

  • 김현정;성주원;은지현;장두성
    • 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
    • /
    • /
    • pp.40-43
    • /
    • 2009
  • 방통융합의 대표적인 서비스인 IPTV의 상용화로 이용자에게는 방송에 대한 다양한 선택의 자유와 편익을 주고 있다. 본 논문에서는 대화시스템을 통해 IPTV 서비스 이용자가 원격 모바일 환경에서 댁내의 IPTV 셋톱장치의 상태를 조회하고 셋톱장치의 환경설정을 변경하거나, IPTV의 채널이나 컨텐츠를 재생할 수 있는 대화시스템의 구조를 제안한다. 이러한 대화시스템을 이용하여 IPTV 사용자는 원격에서 가정내의 자녀들의 TV 시청을 지도하고, 셋톱장치나 리모컨에 익숙하지 않은 유아나 노년층을 위해 원격에서 컨텐츠 재생이 가능하도록 한다. IPTV 영역에 대한 요구 분석을 통해 화행과 의미구조를 수립하였으며, 1만 3천 대화쌍을 수집하였다. 다양한 IPTV 영역에 대응하기 위해 예제기반 추론 방법과 규칙기반 추론 방법을 결합하여 사용할 수 있도록 하였으며, EPG 검색 모듈을 추론모듈에 추가하였다. 또한 SMS 영역에서의 성능향상을 위한 전처리를 도입하였다.

  • PDF

Development Study on Variable Nozzle For Hypersonic Air Breathing Engine

  • Kojima, Takayuki;Taguchi, Hideyuki;Kobayashi, Hiroaki;Fukiba, Katsuyoshi;Sato, Tetsuya;Hatta, Hiroshi;Goto, Ken;Koyanagi, Jun;Aoki, Takuya
    • 한국추진공학회:학술대회논문집
    • /
    • /
    • pp.492-498
    • /
    • 2008
  • In this paper are described recent studies about variable nozzles, that are a rectangular type nozzle and an axisymmetric type nozzle, of the precooled turbojet engine(S-engine) which are developed for the demonstration of the key technologies for the propulsion system of the hypersonic airplane and the first stage propulsion of the TSTO space plane. For the rectangular nozzle, three types of C-shaped carbon/carbon composite cowls which includes subscale model of the precooled turbojet engine are fabricated and the fine attachment to the ramp is confirmed. For the firing of the S-engine, stainless steel cowl with concrete heat insulator are fabricated and tested for 20 sec. Axisymmetric variable plug nozzle which is made of C/C material is fabricated and pressurized by the cold flow test. The axisymmetric plug nozzle can be operative up to 0.57 MPa of nozzle inlet pressure.

  • PDF

Improved Exploration Algorithm Using Reliability Index of Thinning Based Topological Nodes

  • Kwon, Tae-Bum;Song, Jae-Bok;Lee, Soo-Yong
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.250-255
    • /
    • 2005
  • For navigation of a service robot, mapping and localization are very important. To estimate the robot pose, the map of the environment is required and it can be built by exploration or SLAM. Exploration is the fundamental task of guiding a robot autonomously during mapping such that it covers the entire environment with its sensors. In this paper, an efficient exploration scheme based on the position probability of the end nodes of a topological map is proposed. In this scheme, a topological map is constructed in real time using the thinning-based approach. The robot then updates the position probability of each end node maintaining its position at the current location based on the Bayesian update rule using the range data. From this probability, the robot can determine whether or not it needs to visit the specific end node to examine the environment around this node. Various experiments show that the proposed exploration scheme can perform exploration more efficiently than other schemes in that, in most cases, exploration for the entire environment can be completed without directly visiting everywhere in the environment.

  • PDF

동적역량, 운영역량, IT역량이 혁신성과에 미치는 영향 : 탐험과 활용을 중심으로 (The Effect of Dynamic Capabilities, Operational Capabilities, and IT Capabilities on Innovative Performance : Focusing on Exploration and Exploitation)

  • 김문식
    • 한국산학기술학회논문지
    • /
    • v.20 no.1
    • /
    • pp.41-51
    • /
    • 2019
  • 본 연구는 동적역량과 혁신성과 간의 관계를 탐험과 활용의 관점에서 구분된 운영역량과 IT역량이 조절하고 매개하는지를 조사하였다. 178개 기업의 설문지를 분석한 결과, 포착역량과 재구성역량이 점진적 혁신성과와 급진적 혁신성과에 정(+), 탐험적 운영역량과 활용적 운영역량이 점진적 혁신성과에 정(+), 탐험적 운영역량이 급진적 혁신성과에 정(+)의 영향을 미치고 있다. 또한 유의적인 상호작용항은 점진적 혁신성과에 대하여 '탐험적 운영역량*탐험적 IT역량', '탐험적 운영역량*활용적 IT역량', '활용적 운영역량*활용적 IT역량' 등이며, 급진적 혁신성과에 대하여 '탐험적 운영역량*탐험적 IT역량'이다. 유의한 매개효과가 검증된 경우는 7가지였다. 본 연구의 의미는 동적역량이 혁신성과에 미치는 영향을 직접 효과와 간접효과로 나누어 실증적인 연구를 최초로 시도하였으며 운영역량과 IT역량을 탐험과 활용 역량으로 구분하여 정밀한 분석을 하였다는 점이다. 본 연구 결과를 통하여 기업이 적응하고 진화하는데 동적역량과 운영역량이 상호보완적인 역할을 한다는 시사점을 얻을 수 있다.

POMDP와 Exploration Bonus를 이용한 지역적이고 적응적인 QoS 라우팅 기법 (A Localized Adaptive QoS Routing Scheme Using POMDP and Exploration Bonus Techniques)

  • 한정수
    • 한국통신학회논문지
    • /
    • v.31 no.3B
    • /
    • pp.175-182
    • /
    • 2006
  • 본 논문에서는 Localized Aptive QoS 라우팅을 위해 POMDP(Partially Observable Markov Decision Processes)와 Exploration Bonus 기법을 사용하는 방법을 제안하였다. 또한, POMDP 문제를 해결하기 위해 Dynamic Programming을 사용하여 최적의 행동을 찾는 연산이 매우 복잡하고 어렵기 때문에 CEA(Certainty Equivalency Approximation) 기법을 통한 기댓값 사용으로 문제를 단순하였으며, Exploration Bonus 방식을 사용해 현재 경로보다 나은 경로를 탐색하고자 하였다. 이를 위해 다중 경로 탐색 알고리즘(SEMA)을 제안했다. 더욱이 탐색의 횟수와 간격을 정의하기 위해 $\phi$와 k 성능 파라미터들을 사용하여 이들을 통해 탐색의 횟수 변화를 통한 서비스 성공률과 성공 시 사용된 평균 홉 수에 대한 성능을 살펴보았다. 결과적으로 $\phi$ 값이 증가함에 따라 현재의 경로보다 더 나은 경로를 찾게 되며, k 값이 증가할수록 탐색이 증가함을 볼 수 있다.

Firing Test of Core Engine for Pre-cooled Turbojet Engine

  • Taguchi, Hideyuki;Sato, Tetsuya;Kobayashi, Hiroaiki;Kojima, Takayuki;Fukiba, Katsuyoshi;Masaki, Daisaku;Okai, Keiichi;Fujita, Kazuhisa;Hongoh, Motoyuki;Sawai, Shujiro
    • 한국추진공학회:학술대회논문집
    • /
    • /
    • pp.115-121
    • /
    • 2008
  • A core engine for pre-cooled turbojet engines is designed and its component performances are examined both by CFD analyses and experiments. The engine is designed for a flight demonstration of precooled turbojet engine cycle. The engine uses gas hydrogen as fuel. The external boundary including measurement devices is set within $23cm{\times}23cm$ of rectangular cross section, in order to install the engine downstream of the air intake. The rotation speed is 80000 rpm at design point. Mixed flow compressor is selected to attain high pressure ratio and small diameter by single stage. Reverse type main combustor is selected to reduce the engine diameter and the rotating shaft length. The temperature at main combustor is determined by the temperature limit of non-cooled turbine. High loading turbine is designed to attain high pressure ratio by single stage. The firing test of the core engine is conducted using components of small pre-cooled turbojet engine. Gas hydrogen is injected into the main burner and hot gas is generated to drive the turbine. Air flow rate of the compressor can be modulated by a variable geometry exhaust nozzle, which is connected downstream of the core engine. As a result, 75% rotation speed is attained without hazardous vibration and heat damage. Aerodynamic performances of both compressor and turbine are obtained and evaluated independently.

  • PDF

Three-Port Laparoscopic Exploration is not Sufficient for Patients with T4 Gastric Cancer

  • Huang, Hua;Jin, Jie-Jie;Long, Zi-Wen;Wang, Wei;Cai, Hong;Liu, Xiao-Wen;Yu, Hong-Mei;Zhang, Li-Wen;Wang, Ya-Nong
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.19
    • /
    • pp.8221-8224
    • /
    • 2014
  • Gastric cancer continues to be a leading cause of cancer death. The majority of patients with gastric adenocarcinoma in China present with advanced disease. Ruling out unresectable cancers from an unnecessary "open" exploration is very important. The aim of this study was to assess the value of five-port anatomical laparoscopic exploration in T4 gastric cancer in comparison with three-port laparoscopic exploration and laparotomy exploration. We conducted a retrospective study on 126 patients with T4 stage scheduled for D2 curative gastrectomy based on computed tomography (CT) staging at Department of Gastric Cancer and Soft Tissue Sarcoma, Fudan University Shanghai Cancer Center, from Apr. 2011 to Apr. 2013. Laparotomy exploration (Group I), three-port laparoscopic exploration (Group II) or five-port anatomical laparoscopic exploration (Group III) were performed prior to radical gastrectomy. Accuracy rate for feasibility of D2 curative gastrectomy in laparotomy exploration and five-port anatomical laparoscopic exploration groups was higher than that in the three-port laparoscopic exploration group. Five-port anatomical laparoscopic exploration group had the highest accuracy resection rate (Group I vs Group II vs Group III,92.6% vs78.6% vs 97.7%; p<0.05) and shorter length of hospitalization (Group I vs Group II vs Group III, $9.58{\pm}4.17$ vs $6.13{\pm}2.85$ vs $5.00{\pm}1.81$; p<0.001). Three-port laparoscopic exploration has low accuracy rate for assessing feasibility of D2 curative gastrectomy and five-port anatomical laparoscopic exploration should be performed on patients with T4 gastric cancer.

치위생과 학생의 전공만족도, 진로탐색효능감이 진로탐색 행동에 미치는 영향 (Effect of satisfaction in major and career search efficacy on career search behavior in dental hygiene students)

  • 정기옥;최규일;배지영
    • 한국치위생학회지
    • /
    • v.13 no.1
    • /
    • pp.61-68
    • /
    • 2013
  • Objectives : The purpose of this research is to identify the effect of Dental Hygienic students' level of satisfaction towards their major and sense of career exploration efficacy on their career exploration behavior so that the key findings of this research will help the university students to explore career related to their major and to assume rational attitude towards their career path. Methods : The study was conducted targeting 450 university students who are studying in the Department of Dental Hygienic at the four universities located in Daegu, Gyeongsangbuk-do and Chungcheongbuk-do. Data collection was carried out using the self-administered questions based on the use of structured survey questionnaire, and analysis was conducted using frequency analysis, descriptive statistics, ANOVA, correlation analysis, and multiple regression analysis. Results : 1. Total grade of the Dental Hygienic students' level of satisfaction towards their major was $3.36{\pm}.49$ points, while total grade of the sense of career exploration efficacy was $3.06{\pm}.46$ points. In case of the career exploration behavior, the total grade was $2.76{\pm}.53$ points. 2. In case of the level of satisfaction towards their major, there was a significant difference depending on the class, grade and motivation for admission. As for the sense of career exploration efficacy and career exploration behavior, there was a significant difference depending on grade. 3. Sense of career exploration efficacy and career exploration behavior demonstrated level of satisfaction towards their major manifested positive correlation. Sense of career exploration efficacy manifested positive correlation career exploration behavior. 4. As for the elements that affect Dental Hygienic students' career exploration behavior, they were level of satisfaction towards their major and sense of career exploration efficacy, and the explanatory power was 19.0%. Conclusions : It should be necessary to study the elements that affect Dental Hygienic students' career exploration behavior in greater depth using diverse methods and information in order to increase sense of career exploration efficacy so that the individual Dental Hygienic students can engage in detailed career exploration behavior for the sake of their career path.

The Effects of Secondary Fuel Injection on Combustion Oscillation

  • Shigeru Tachibana;Laurent Zimmer;Park, Gyung-Min;Takeshi Yamamoto;Ufosawa, Yoji-K;Seiji Yoshida;Kazuo Suzuki
    • 한국추진공학회:학술대회논문집
    • /
    • /
    • pp.376-379
    • /
    • 2004
  • The purpose of this work is to develop an effective active control system for combustion instabilities of premixed combustors. For the first step, the natural modes of combustion oscillation were investigated for a methane-air premixed combustor and the controls by secondary fuel injection were examined. The main premixed flame is stabilized by a swirler with orifices for secondary injection installed on the central hub. For sensing purposes, a pressure transducer and a chemiluminescence sensor were placed on the appropriate positions. The acoustic characteristics and the source of the oscillation were analyzed by those signals. To test the controllability, two methods of actuations by secondary fuel injection were examined. One is the open loop control and the other is the closed loop control. The comparison of the reduction levels of p $_{rms}$ shows that the closed loop control with a phase-shift injection performs best in this condition.ition.n.

  • PDF

TD(${\lambda}$) 기법을 사용한 지역적이며 적응적인 QoS 라우팅 기법 (A Localized Adaptive QoS Routing using TD(${\lambda}$) method)

  • 한정수
    • 한국통신학회논문지
    • /
    • v.30 no.5B
    • /
    • pp.304-309
    • /
    • 2005
  • 본 논문에서는 TD(temporal differences) 기법을 사용한 localized QoS 라우팅 기법을 제안하였다. 이 기법은 이웃노드로부터 얻어지는 성공 기댓값을 통해 라우팅 정책을 결정하는 기법이다. 이에 본 논문에서는 라우팅 성공 기댓값을 기반으로 한 다양한 탐색기법으로 경로 선택 시 라우팅 성능을 비교 평가하였으며, 특히 Exploration Bonus를 적용한 탐색 기법이 다른 탐색 기법에 비해 더욱 우수한 성능을 보여주고 있는데, 이는 다른 탐색 기법에 비해 네트워크 상황에 더 적응적으로 경로를 선택할 수 있기 때문이다.