• 제목/요약/키워드: Mixed Functions

검색결과 445건 처리시간 0.022초

$H_\infty$제어에 의한 병렬형 도립진자의 제어에 관한 연구 (A Study on the Control of Parallel-Type Inverted Pendulum by $H_\infty$ Control)

  • 양주호;변정환
    • 수산해양기술연구
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    • 제31권2호
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    • pp.178-189
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    • 1995
  • 병렬형 도립진자를 수학적으로 모델링하고 주파수 응답법에 의해 파라미터를 동정하여, $H_\infty$제어이론 중 혼합감도문제에 의거하여 제어계를 설계한 후 응답 시뮬레이션을 한 결과그 응답으로부터 모델링의 불확실성에 대처할 수 있는 강인한 제어계를 구성할 수 있었다. 앞으로 실제 시스템에 대하 s제어들 과제로 남겨두고 있다. 시뮬레이션 응답과는 달리 실제 으답실험에서도 좋은 결과를 얻기 위해서는 여러 가지의 어려움이 있을 것으로 예상된다. 특히 응답 시뮬레이션에서도 나타난 바와 같이 전자가 미소각으로 기울어진 상태에서 제어를 할 경우에도 각 상태의 변동량이 크고, 또한 상당한 제어입력을 요한다. 따라서 센서 잡음에 대한 영향을 충분히 고려할 필요가 있으므로, 노이즈를 많이 발생시키는 PWM방식의 직류모터 구동 드라이버보다는 선형 드라이버를 이용하는 것이 적절할 것으로 예상된다

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Gaussian분포의 질량함수를 사용하는 Dempster-Shafer영상융합 (Dempster-Shafer Fusion of Multisensor Imagery Using Gaussian Mass Function)

  • 이상훈
    • 대한원격탐사학회지
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    • 제20권6호
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    • pp.419-425
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    • 2004
  • 본 연구에서는 Dempster-Shafer evidence theory에 기반하여 Gaussian 질량 함수를 사용하는 융합 기법을 제안하고 있다. Dempster-Shafer 융합은 비정확성과 불확실성 measures를 각각 belief 함수와 plausibility 함수로 나타내며 이 두 함수 값 사이의 간격을 나타내는 "belief interval"에 의해 불확실성의 정도가 표현된다. 이러한 Dempster-Shafer 융합기술을 이용하여 서로 다른 센서에서 수집된 영상 자료를 융합하여 사용하여 분류 결과의 정확성을 높이고 특히 분류를 위한 매개변수를 추정하는 훈련과정에서 복합 클래스를 설정할 수 있어 단순 클래스 설정으로 인한 훈련과정이 어려움을 피할 수 있다. 이 연구에서는 경기도 용인/능평 지역에서 관측 된 KOMPSAT EOC의 범색 영상 자료와 LANDSAT ETM+의 식생지수 자료에 대해 제안된 Dempster-Shafer 융합기술을 이용하여 분류 실험을 수행하였고 분류 결과는 서로 다른 센서간의 영상자료 융합을 위한 제안된 기법의 잠재적 효과성을 보여주고 있다.

유기 리간드 제어를 통한 고분산 팔라듐 나노 촉매의 합성 및 음이온교환막 연료전지를 위한 산소 환원 반응 특성 분석 (Synthesis of Highly Dispersed Pd Nanocatalysts Through Control of Organic Ligands and Their Electrochemical Properties for Oxygen Reduction Reaction in Anion Exchange Membrane Fuel Cells)

  • 성후광;;장정희;정남기
    • 한국재료학회지
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    • 제28권11호
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    • pp.633-639
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    • 2018
  • In anion exchange membrane fuel cells, Pd nanoparticles are extensively studied as promising non-Pt catalysts due to their electronic structure similar to Pt. In this study, to fabricate Pd nanoparticles well dispersed on carbon support materials, we propose a synthetic strategy using mixed organic ligands with different chemical structures and functions. Simultaneously to control the Pd particle size and dispersion, a ligand mixture composed of oleylamine(OA) and trioctylphosphine(TOP) is utilized during thermal decomposition of Pd precursors. In the ligand mixture, OA serves mainly as a reducing agent rather than a stabilizer since TOP, which has a bulky structure, more strongly interacts with the Pd metal surface as a stabilizer compared to OA. The specific roles of OA and TOP in the Pd nanoparticle synthesis are studied according to the mixture composition, and the oxygen reduction reaction(ORR) activity and durability of highly-dispersed Pd nanocatalysts with different particles sizes are investigated. The results of this study confirm that the Pd nanocatalyst with large particles has high durability compared to the nanocatalyst with small Pd nanoparticles during the accelerated degradation tests although they initially indicated similar ORR performance.

Effect of Allium hookeri Root on Physicochemical, Lipid, and Protein Oxidation of Longissimus Dorsi Muscle Meatball

  • Yoon, Dong-kyu;Kim, Ji-Han;Cho, Won-Young;Ji, Da-Som;Lee, Ha-Jung;Kim, Jung-Ho;Lee, Chi-Ho
    • 한국축산식품학회지
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    • 제38권6호
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    • pp.1203-1215
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    • 2018
  • The antioxidant effects of Allium hookeri root (AHR) were investigated by evaluating lipid and protein oxidation in meatballs during refrigerated storage at $4{\pm}1^{\circ}C$. AHR was mixed at concentrations of 0.5% (w/w, T2) and 1% (w/w, T3) with minced longissimus dorsi muscle. Meatballs containing AHR (T2 and T3) were compared to those containing 0.05% (w/w) ascorbic acid (T1) as a reference and without antioxidant as a control. The 2-thiobarbituric acid reactive substances (TBARS) value, disulfide bond formation, carbonyl contents, and volatile basic nitrogen (VBN) value of T2 were lower than those of the control during storage (p<0.05). The pH values of T2 and T3 were higher than that of the control (p<0.05). Texture profile analysis of T2 revealed a lower value compared to the control (p<0.05). Therefore, the VBN value, TBARS value, disulfide bond formation, and carbonyl content in meatball containing AHR were lower than those of the control meatball. These results indicate that AHR improves the quality of meat products and functions as an antioxidant.

A Study on The Usability Evaluation Based on Text Analysis for The Development of Comfort-Shoes for Middle-Aged

  • KIM, Ji Ho;YOON, Sang Hoon;KWON, Ki Hyun;SEO, Jeong Kwon;HAN, Seung Jin
    • Journal of Sport and Applied Science
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    • 제3권2호
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    • pp.17-27
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    • 2019
  • Purpose: This study is to conduct usability evaluations from the perspective of developing comfort-shoes for the middle-aged and elderly to identify key factors and derive implications for optimal comfort-shoes production. Research design, data, and methodology: A total of 10 middle-aged and elderly women in their 50s and 60s were selected as eligible for the rescue. For data collection, the study was conducted in a Gang Survey, where pre-explanations, shoes test, and interviews were conducted. The collected data were analyzed in a total of four stages. In step 1, the contents obtained through interviews with the subjects were recorded in text, organized and analyzed systematically, and in step 2, unnecessary vocabulary, sentences, and overlapping opinions were eliminated. In step 3, we classified areas around key functions and carried out categorization tasks. Finally, in Step 4, the results and implications of the study were derived by classifying each usability evaluation shoe as positive and negative text around categorized data. Results: There are a total of seven factors for comfort-shoes usability evaluation, which are categorized as cushion, fitting, stability, flexibility, lightweight, comfort, and pressure. Positive/negative factors for the derived usability evaluation factors were shown in the form of a positive-centered, negative-centered, and positive-mixed mix for each of the four products. Positive-focused products are VA products, which are seven times more positive than negative factors. Negative-centered products are CL and SA products, which are five times more negative than positive factors. Positive mixing was a CA product with a ratio of 1:1. Text-based usability evaluations allow us to proceed with analysis based on more scientific data rather than simply listening to opinions and judging by comments. Conclusions: The study discussed implications of developing comfort-shoes for middle-aged consumers and future directions were discussed.

마우스 수지상세포의 항원 제시 능력에 대한 이온화 규소수의 biphasic 면역조절 효과 (Biphasic immunomodulatory effects of ionized biosilica water on the antigen-presenting capability of mouse dendritic cells)

  • 이유정;주홍구
    • 대한수의학회지
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    • 제61권2호
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    • pp.14.1-14.7
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    • 2021
  • Biosilica is a silica-based substance derived from the cell walls (frustules) of diatoms. Recently, research into biosilica's biological functions is underway, but little has been reported on the effects of biosilica on immune cells. In this study, we investigated the effect of ionized biosilica water (iBW) on dendritic cells (DCs), which play crucial roles as antigen (Ag)-presenting cells. Treatment with iBW increased the expression of immune response-related markers, closely connected to the maturation of DCs, and the production of tumor necrosis factor-alpha. In addition, iBW-treated DCs (iBW-DCs) had a lower uptake of fluorescein isothiocyanate-dextran than that of control DCs. Mixed leukocyte response analysis used for measuring the Ag-presenting capability of DCs, showed iBW-DCs had a higher capability than that of control DCs. Interestingly, DCs treated with lipopolysaccharide (LPS) and iBW had a lower level of Ag-presenting capability than that of LPS-treated DCs. Taken together, the results indicate that iBW alone can mature DCs, but it decreases the Ag-presenting capability of DCs in the presence of LPS, a representative agent of inflammation. This study may provide valuable information regarding the effect of iBW on immune cells. Further research is needed to investigate how iBW induces the observed biphasic immunomodulatory activity.

선제 발화하는 대화형 에이전트가 사용자 경험에 미치는영향: 사용자 과제 수행과 대화형 에이전트의 자기노출을 중심으로 (Preceded Utterance Conversational Agent's Effect on User Experience with User's Task Performance and Conversational Agent's Self-Disclosure)

  • 신효림;이소연;강현민
    • 문화기술의 융합
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    • 제8권1호
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    • pp.565-576
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    • 2022
  • 대화형 에이전트의 사용 범위와 기능이 점차 확장되고 있다. 특히나, 사용자의 호출이 있어야만 말을 하는 대화형 에이전트에서 사용자의 호출 없이도 먼저 말을 걸 수 있는 선제 발화하는 대화형 에이전트에 대한 연구와 기술개발이 이루어지고 있다. 그러나 아직 초기 단계이기 때문에 선제 발화하는 대화형 에이전트가 사용자에게 어떠한 영향을 미칠지에 대한 연구가 부족한 상황이다. 이에 이 연구는 선제 발화하는 대화형 에이전트가 사용자 경험에 미치는 영향을 확인하기 위해 사용자의 과제 수행 조건과 에이전트의 자기노출 유무를 독립변인으로 하는 2×3 혼합 설계를 통해 친밀감, 기능적 만족감, 심리적 저항감, 작업 부하를 측정하였다.

Professional Mobility as a Factor of Professional Success of a Modern Specialist in the Conditions of Distance Learning

  • Semchuk, Bohdan;Havryliuk, Svitlana;Karnaukh, Lesia;Balakirieva, Viktoriia;Palshkova, Iryna;Leonova, Veronika;Bida, Olena
    • International Journal of Computer Science & Network Security
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    • 제22권8호
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    • pp.260-268
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    • 2022
  • The article considers the training, competitiveness of specialists, professional mobility, professionalism and competence of specialists in the context of distance learning. The advantages of distance learning are shown. The characteristic features of distance learning in the preparation of students and in the implementation of these technologies in the educational process of higher educational institutions are determined. Competitiveness, professional mobility, professionalism and competence of a specialist are qualities that determine a person's life and work success. Professional mobility is interpreted as a systemic quality of a specialist's personality, which includes a whole range of knowledge, skills, abilities, personal qualities, value orientations, and so on. The vision of mobility of specialists by foreign scientists is presented. It is noted that the classification of professional mobility presented in the article makes it possible to organize various movements from a single position, to present them as separate manifestations of the general process of professional and pedagogical mobility, to determine which type of mobility ensures the performance of certain social functions. It was found that mobility can be differentiated into differentiated and intergeneration. According to the subject, individual and group mobility are distinguished; according to the direction - internal and external. The classification of employees according to their attitude to mobility is shown, which can be divided into the following groups: actually mobile; potentially mobile; actually stable; potentially stable.

공공도서관 기반 미디어 리터러시 교육 모형 개발 (The Development of a Media Literacy Educational Model for Public Libraries in South Korea)

  • 박주현;이명규;김지현;강봉숙;이지수;심효정
    • 한국문헌정보학회지
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    • 제56권3호
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    • pp.335-362
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    • 2022
  • 본 연구의 목적은 공공도서관 사서가 미디어 리터러시 교육 프로그램을 기획하고 운영하는 데 도움이 되는 미디어 리터러시 교육 모형을 개발하는 데 있다. 교육 모형을 개발하기 위하여 문헌연구, 사서 대상 설문조사, 미디어 리터러시 관련 교수와 공공도서관 사서, 강사를 대상으로 인터뷰를 진행하였으며 전문가 자문위원회를 개최하여 개발한 모형에 대해 의견을 얻었다. 설문조사와 인터뷰 결과, 공공도서관과 사서는 시민들의 미디어 리터러시 향상에 대한 책무성이 있으며 공공도서관이 시민들의 미디어 리터러시를 향상시킬 수 있는 최적의 교육기관으로 인식되고 있었다. 문헌분석 결과와 미디어 리터러시 전문가들의 의견을 반영하여 교육 목적, 핵심역량, 교육 대상, 미디어의 종류, 교육 주체별 역할과 기능이 포함된 미디어 리터러시 교육 모형을 개발하였다.

Changes of Temporal Processing and Hearing in Noise after Use of a Monoaural Hearing Aid in Patients with Sensorineural Hearing Loss: A Preliminary Study

  • Kim, Yehree;Yang, Chan Joo;Yoo, Myung Hoon;Song, Chan Il;Chung, Jong Woo
    • Journal of Audiology & Otology
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    • 제25권3호
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    • pp.146-151
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    • 2021
  • Background and Objectives: The relationship between hearing aid (HA) use and improvement in cognitive function is not fully known. This study aimed to determine whether HAs could recover temporal resolution or hearing in noise functions. Materials and Methods: We designed a prospective study with two groups: HA users and controls. Patients older than 45 years, with a pure tone average threshold of worse than 40 dB and a speech discrimination score better than 60% in both ears were eligible. Central auditory processing tests and hearing in noise tests (HINTs) were evaluated at the beginning of the study and 1, 3, 6, and 12 months after the use of a monaural HA in the HA group compared to the control group. The changes in the evaluation parameters were statistically analyzed using the linear mixed model. Results: A total of 26 participants (13 in the HA and 13 in the control group) were included in this study. The frequency (p<0.01) and duration test (p=0.02) scores showed significant improvements in the HA group after 1 year, while the HINT scores showed no significant change. Conclusions: After using an HA for one year, patients performed better on temporal resolution tests. No improvement was documented with regard to hearing in noise.