• 제목/요약/키워드: Charge distribution

검색결과 704건 처리시간 0.024초

대구시 도시근린공원의 접근성에 따른 환경적 형평성 분석 (Environmental Equity Analysis of the Accessibility of Urban Neighborhood Parks in Daegu City)

  • 서현진;전병운
    • 한국지리정보학회지
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    • 제14권4호
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    • pp.221-237
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    • 2011
  • 본 연구는 환경정의 관점에서 도시근린공원의 접근성에 따른 형평성을 대구시를 사례로 분석하였다. 이를 위해 근린공원의 공간통계학적 분포 특성을 살펴 본 후, 최소거리 및 커버리지 접근 방법을 이용하여 접근성을 측정하였다. 여기에서 도출된 접근성에 따른 사회 경제적 특성을 비교하기 위해 근접비율, 맨 휘트니 U 검정, 로지스틱 회귀분석 등과 같은 기술적 추론적 통계를 이용하여 분석하였다. 최소거리 분석에서는 자치구 중 달서구가 근린공원에 대한 접근성이 가장 양호하며, 동구가 가장 불량한 것으로 나타났다. 커버리지 분석에서는 500m와 1,000m 모두 접근성이 가장 양호한 자치구는 달서구, 가장 불량한 자치구는 동구와 남구로 분석되었다. 환경적 형평성 분석 결과 구시가지는 대부분 고령자비율에서 환경적 형평성이 있는 것으로 나타났고, 인구밀도 및 미성년자 비율에서 불형평성이 나타났다. 신시가지는 대부분 인구밀도 및 미성년자 비율에서 환경적 형평성이 있는 것으로 나타났고, 고령자비율과 기초생활수급자비율 및 무상주택비율에서 불형평성이 나타났다. 이러한 결과는 정량적인 도시공원정책에 의한 대구시 도시공원의 조성과정 및 도시개발과정과 영구임대주택의 입지패턴과 밀접한 연관성을 가지고 있었다. 본 연구는 기존의 유해시설과 관련된 환경정의 연구의 주제를 확장하였으며, 도출된 분석결과는 대구시에서 사회 경제적 특성을 반영한 도시공원정책을 수립할 때 기초자료로 활용될 수 있다.

서울지역 일 여자 상업고등학교의 성에 대한 지식 및 태도에 관한 연구 (A Study on the Knowledge and Attitude about Sex in One Commercial Girls' High school in Seoul)

  • 김은희
    • 한국학교보건학회지
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    • 제4권2호
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    • pp.100-118
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    • 1991
  • This study was conducted in order to grasp the condition of the student's knowledge and attitude about sex. And to offer the basic materials for sex education of school health service. The objects were comprised of 464 volunteered students who study in commercial girls' high school. The material of this study was the questionaire suited to the purposed of this research which has been made through studying references. All the questionaire written by students. The self reported questionaires were collected immediately without explanation on supervision of school nurse. The data was collected from 28th to 30th of June on 1990. Analysis of the data was done utilizing SPSS for percentage, mean, ANOVA and Pearson Correlation Coefficients. The Results are as follows; 1. General features of the objects of study School grade distribution was similar. Fathers of 41-50 years were the highest(58.3%), mothers of 41-50 years were the highest(64.3%), family of living together were the highest(87.5%), fathers of graduated high school were highest(60.7%), mothers of graduated middle school were the highest(43.0%) and neuclear families were highest(91.5%). 2. The Conditions of Knowledge about sex When 5 Point was given to "Well known" and 1 point was given to "Never known", the total average was 2.97, Especially the mean of Female physiology was shown 3.93, 73.4% of students have known. But the mean of male physiology was shown 2.23, 17.2% of students only. And Family planning item was 3.54, hymen item was 3.38, female genitalia item was 3.35, abortion item was 3.25, Intercourse and pregnancy item was 3.24, Ovulation item was 3.02, Contraception item was 2.97, Veneral disease and masturbation item was 2.82, maintenance of pregnancy item was 2.76, Anatomical differences between male and female item was 2.59, male genitalia item was 2.31, ejaculation item was 2.27. 3. The conditions of attitude about Sex When 5 point was given to "Very affirming" and 1 point was given to "Very deny" the total average was 3.20. Especially the mean of social intercourse between other sex was shown 3.92, 73.4% of students have affirmed. But the mean of psychic response on menstruation was shown 2.24, 8.8% of students only. And baby birth item was 3.72, the fact that I am a woman item was 3.53, marriage item was 3.49. Secondary body change item was 3.38, puberty item was 3.31, delivery and sexual intercourse item was 3.05, pregenancy item was 3.02, psychic condition on menarche item was 2.50. Also present counsellors about sex were teachers in charge (44.9%), friends(21.6%), mothers(20.6%), elder sisters (10.6%), mass-communications (1.5%), fathers (0.4%), school nurses and elder brother(0.2%). In addition to, future counsellors about sex were friends (37.7%), mothers(30.6%), elder sister (18.4%), school nurses (4.6%), mass communication (3.8%), teachers in charge (2.5%), elder brothers (1.4%) and fathers(1.0%). 4. Correlation between the general features and knowledge variables School grade and knowledge condition has relationship to female genitalia(P<0.05), female physiology (P<0.00), male physiology (P<0.05),ovulation (P<0.00), and femily planning (P<0.005). Fathers age and knowledge condition has relationship to male physiology(P<0.05), and abortion (P<0.05). Marrital status and knowledge condition has relationship to female physiology (P<0.01), masturbation (P<0.05). Fathers educational background and knowledge condition has relationship to masturbation (P<0.00). Mothers age and knowledge condition has relationship to family planning (P<0.05). 5. Correlation between the general futures and attituded variables Fathers age and attitude condition has relationship to psychic response on menstruation (P<0.05). Mothers age and attitude condition has relationship to fact that I am a woman (P<0.00). Mothers educational background and attitude condition has relationship to social intercourse between other sex (P<0.05). Type of family and attitude condition has relationship to puberty (P<0.01). 6. Correlation between knowledge condition and attitude condition Those who had more knowledge about sex have more affirmative response (P<0.001).

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Optical Properties of Oxotitanium (Ⅳ) Meso-tetrakis(4-sulfonatophenyl)porphyrin Intercalated into the Layered Double Hydroxides (LDH) Studied by Laser Spectroscopy

  • Ryu, Su-Young;Yoon, Min-Joong;Choy, Jin-Ho;Hwang, Sung-Ho;Frube, Akihiro;Asahi, Tsuyoshi;Hiroshi, Masuhara
    • Bulletin of the Korean Chemical Society
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    • 제24권4호
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    • pp.446-452
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    • 2003
  • Some new nanohybrid materials have been synthesized by intercalating the oxotitanium(IV) meso-tetrakis(4- sulfonatophenyl) porphyrin$(O=Ti^{(IV)} TSPP)$ into the Zn/Al layered double hydroxides (LDHs), and their structures and photophysical properties have been investigated by various laser spectroscopic techniques. According to the XRD pattern of the synthesized nanohybrid materials, the macrocycle plane of $O=Ti^{(IV)}$ TSPP are grafted perpendicular to the LDH layers. The $O=Ti^{(IV)}$ TSPP-intercalated LDH exhibits band broadening of the absorption spectrum and a blue shift of Q-band as compared to that observed in solution. Resonance Raman spectral measurements demonstrate that the positively charged LDHs give rise to a slight decrease of the electronic density of the porphyrin ring accompanying a small change of the electronic distribution of the $O=Ti^{(IV)}$ TSPP. Consequently the LDH environment affects the energies of the two highest occupied molecular orbitals (HOMOs) of the $O=Ti^{(IV)}$) TSPP, $a_{1u}$ and $a_{2u}$, producing a mixed orbital character. Being consistent with these electronic structural changes of $O=Ti^{(IV)}$ TSPP in LDH, both the fluorescence spectral change and the fsdiffuse reflectance transient measurements imply that the photoexcitation of the $O=Ti^{(IV)}$ TSPP intercalated into LDH undergoes fast relaxation to the O=Ti(IV) $TSPP^+-LDH^- $charge transfer (CT) state within a few picoseconds, followed by a photoinduced electron transfer between the O=Ti(IV) TSPP and LDHs with a rate constant greater than %1×10^{10}S^{-1}$. No evidence is found for back electron transfer. In conclusion, the $O=Ti^{(IV)}$ TSPP intercalated LDH seems to be a possible candidate for an artificial reaction center for an efficient solar energy conversion system.

MgO계 세라믹 모르타르를 활용한 콘크리트 보수재료의 기초물성평가 (Fundamental Properties of MgO Base Ceramic Mortar for Concrete Repair Material)

  • 박준우;안기용
    • 콘크리트학회논문집
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    • 제29권4호
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    • pp.407-413
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    • 2017
  • 본 연구는 콘크리트 보수재료로서의 MgO계 세라믹(Magnesia Phosphate Cement: MPC) 모르타르의 기초물성 평가를 위한 것이다. 이를 위해 응결시간, 압축강도, 부착강도를 측정하였으며 수화물의 측정을 위해 X-ray 회절분석을 실시하였다. 시편은 중질 마그네시아(dead burnt magnesia)를 바인더로 사용하였으며 활성제로 칼륨계 인산염을 사용하였고, 응결시간을 지연 시키기 위해 Borax를 지연제로 사용하였다. 또한, 이온침투저항성 평가를 위해 공극구조와 촉진염화물침투시험을 실시하였다. 그 결과 MPC 모르타르의 응결시간은 M/P 비에 따라 16~21분 사이로 빠르게 경화하였으며 지연제인 Borax는 MPC의 응결시간을 68분까지 늦추는 데 도움이 되었다. MPC 모르타르의 압축 강도는 12시간 재령에서 M/P 비에 따라 11.0~30.0 MPa 범위로 발현되었고 특히 M/P 비가 4인 MPC의 압축 강도는 12시간 이내에 30 MPa 정도의 강도를 발현하였다. MPC의 인장 부착강도와 휨 부착강도는 OPC 모르타르에 비해 각각 19 MPa와 17 MPa로 더 높게 측정되었으며 MPC 모르타르의 총 공극량은 OPC 모르타르에 비해 적게 측정되었고 촉진염화물침투시험에서도 MPC 모르타르를 통과한 총 전하가 OPC 모르타르보다 적었으며 이는 공극량과 공극분포로 설명 할 수 있다.

Effects of reversible metastable defect induced by illumination on Cu(In,Ga)Se2 solar cell with CBD-ZnS buffer layer

  • Lee, Woo-Jung;Yu, Hye-Jung;Cho, Dae-Hyung;Wi, Jae-Hyung;Han, Won-Seok;Yoo, Jisu;Yi, Yeonjin;Song, Jung-Hoon;Chung, Yong-Duck
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.431-431
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    • 2016
  • Typical Cu(In,Ga)Se2 (CIGS)-based solar cells have a buffer layer between CIGS absorber layer and transparent ZnO front electrode, which plays an important role in improving the cell performance. Among various buffer materials, chemical bath deposition (CBD)-ZnS is being steadily studied to alternative to conventional CdS and the efficiency of CBD-ZnS/CIGS solar cell shows the comparable values with that of CdS/CIGS solar cell. The intriguing thing is that reversible changes occur after exposure to illumination due to the metastable defect states in completed ZnS/CIGS solar cell, which induces an improvement of solar cell performance. Thus, it implies that the understanding of metastable defects in CBD-ZnS/CIGS solar cell is important issue. In this study, we fabricate the ITO/i-ZnO/CBD-ZnS/CIGS/Mo/SLG solar cells by controlling the NH4OH mole concentration (from 2 M to 3.5 M) of CBD-ZnS buffer layer and observe their conversion efficiency with and without light soaking for 1 hr. From the results, NH4OH mole concentration and light exposure can significantly affect the CBD-ZnS/CIGS solar cell performance. In order to investigate that which layer can contain metastable defect states to influence on solar cell performance, impedance spectroscopy and capacitance profiling technique with exposure to illumination have been applied to CBD-ZnS/CIGS solar cell. These techniques give a very useful information on the density of states within the bandgap of CIGS, free carriers density, and light-induced metastable effects. Here, we present the rearranged charge distribution after exposure to illumination and suggest the origin of the metastable defect states in CBD-ZnS/CIGS solar cell.

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수산물의 유통단계별 가격간 장기균형관계와 인과성 분석 -부산지역의 갈치, 오징어를 중심으로- (A Study on the Long-run Equilibrium Relationship and Causality between the Prices of Fisheries Products at Different Levels of Distribution -Focused on Hairtail and Squid in Pusan-)

  • 강석규;이광진
    • 수산경영론집
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    • 제29권2호
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    • pp.77-96
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    • 1998
  • Fisheries products in Korea generally go through three markets, namely the wholesale market at production site (Market A), the wholesale market at consumption site (Market B), and the retail market (Market C), from producers to end consumers. As the products move from Market A through Market B to Market C, the marginal gap of prices asked in these markets demonstrates an apparent relationship. The producers, middlemen, consumers, and governmental departments concerned may influence the marketing prices of fisheries products. This study employing the cointegration theory tries to investigate whether causality of the price-setting among these markets exists and, if any, what it is. The authors have focused their attention on fisheries markets in Pusan, analyzing the long-run equilibrium relationship and causality between the prices of hairtail and squid among markets at different levels. Data used in this study cover the period f개m August 1984 to December 1997 fer hairtail, and the period from May 1989 to December 1997 for squid. The main findings of the study may be summarized as follows: First, regardless of the price time-series of hairtail and squid in individual market, the first difference is necessary fur satisfying the stationary conditions since each time-series is a first integration. This means homogeneous integration of time-series, which is a requirement of the long-run equilibrium of prices at different markets, is satisfied. Second, the study of the long-run equilibrium relationship between the prices at Market A and Market B shows that a long-run equilibrium relationship does exist for selling prices of the two species at Market A and Market B. Third, the ECM (error correction model ) used here to describe the long- and short-run dynamics of price change demonstrates that, in the case of squid, the price change in Market A will lead to a corresponding price change in Market B in the long-run period. In the short-run, however, the price at Market H is not only influenced by the price change in Market A but influence the price at Market A as well, that is, the Prices between Market A and Market B have a feedback effect. It should be stressed that the limitation in data collection, which cover only two species of hairtail and squid, is likely to cause a sampling bias. Nonetheless, we may conclude that a dynamic relation in the formation of prices does exist in view of the transaction amount of species at different markets. It is believed that the conclusion drawn from this study would not only contribute to a long-lasted debate on the direction of causality of price-setting among academic circle and fishing community, but would provide a useful standard for the policy makers in charge of the price-setting of fisheries products as well.

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국내 학술지의 오픈액세스 특성에 관한 연구: KCI 등재지를 대상으로 (A Study on the Characteristics of Open Access in Korean Scholarly Journals: Focused on KCI Journals)

  • 김규환;정경희
    • 정보관리학회지
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    • 제34권3호
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    • pp.251-267
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    • 2017
  • 본 연구는 KCI 등재지 1,890종을 대상으로 국내 학술지의 오픈액세스의 주요 특성을 분석하고자 하였다. 이를 위해서 학술지의 오픈액세스 특성을 무료접근과 자유로운 재사용이라는 2가지 측면으로 구분하였다. 분석결과, 국내 학술지의 오픈액세스 특성은 무료접근적 성향이 강하였다. 학술지 홈페이지를 기준으로 보면 67%가 로그인 없이 무료로 접근할 수 있었고 무료DB를 기준으로 보면 48%가 무료로 접근할 수 있었다. 반면 자유로운 재사용적 성향은 무료접근적 성향에 비해 약한 것으로 나타났다. 전체 등재지 중에서 14%만이 CC 라이선스를 부여하고 있었다. 또한 주제분야간에 오픈액세스 성향의 차이가 분명하게 나타났다. 의약학, 자연과학, 농수해양, 공학 분야가 인문학, 사회학, 예술체육, 복합학 분야에 비해 오픈액세스 성향이 상대적으로 강한 것으로 나타났다. 그 이유는 해당 주제분야의 학술지 유통을 지원해 주는 기관의 존재 유무에 따라 차이가 발생한 것으로 보인다. 이런 문제를 해결하기 위해서는 주제분야와 상관없이 국내 학술지의 오픈액세스 정책을 수립하고 지원하는 오픈액세스 거버넌스 체제가 구축될 필요가 있다.

GIS 예방진단시스템을 위한 TMO 응용 데이터 수집 시스템 (Data Acquisition System Applying TMO for GIS Preventive Diagnostic System)

  • 김태완;김윤관;장천현
    • 정보처리학회논문지A
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    • 제16A권6호
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    • pp.481-488
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    • 2009
  • 가스절연개폐장치(Gas Insulated Switchgear:GIS)는 SF6가스를 절연 매체로 하는 대용량 전력 차단기기이다. GIS는 단순한 구조로 고장이 적고 신뢰성이 높은 편이지만 내부를 볼 수 없어 고장 확인이 어렵고 고장이 발생하면 파급 효과가 크고 복구가 어렵다. 따라서 GIS 내부의 이상 징후를 초기에 찾아낼 수 있도록 GIS 예방진단시스템이 도입되었다. GIS 예방진단시스템은 센서에서 수집, 분석한 정보로 이상 징후를 판 단하기 때문에 데이터의 신뢰성과 적시성이 중요하다. 하지만 기존 시스템은 중앙 집중 데이터 수집 방식으로 효율이 낮고 신뢰성과 적시성의 보장이 어렵다. 이러한 신뢰성과 적시성을 보장하기 위하여 GIS 예방진단시스템은 실시간성을 보장하는 미들웨어를 탑재해야 한다. 따라서 본 논문에서는 GIS 예방진단시스템의 신뢰성 향상을 위하여 실시간 분산 컴퓨팅의 적시성 보장을 위해 제안된 TMO를 적용한 미들웨어를 사용한 다. 그리고 TMO를 적용한 데이터 수집 및 감시, 제어 방법을 적용한 새로운 GIS 예방진단 시스템을 제안한다. 논문에서 제안하는 시스템은 TMO의 실시간 기능을 활용하여 데이터의 분산 처리가 가능한 통신제어장치를 개발하여 사용한다. 통신제어장치는 TMO를 통해 실시간 데이 터 수집 및 처리 과정의 적시성을 보장하고 데이터의 신뢰성을 높여 시스템의 성능 향상에 기여한다. 또한, 기존의 서버의 데이터 수집 및 처 리 과정을 통신제어장치가 부담하여 서버의 부하를 줄이고 향후 분산 환경을 지원할 수 있도록 설계하였다. 따라서 제안하는 시스템은 통신제 어장치의 적시성 보장을 통해 GIS 예방진단시스템의 신뢰성과 성능을 향상시키고 GIS의 안정적인 운영을 보장할 수 있다.

P2P 기반의 모바일 상거래를 위한 동적 그룹 인증 (The Dynamic Group Authentication for P2P based Mobile Commerce)

  • 윤성현
    • 디지털융복합연구
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    • 제12권2호
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    • pp.335-341
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    • 2014
  • 사용자 스마트폰에서 네트워크 비디오를 실시간으로 재생하려면, 서버가 비디오 콘텐츠를 스트리밍 방식으로 전송해야 한다. 일반적으로 상거래 서버는 유료 가입자 인증과 콘텐츠 분배를 담당한다. 단점은 사용자들의 서비스 요구가 급증하면 서버의 과부하, 전송 대역폭의 제한으로 고객에게 돌아가는 서비스 품질이 저하된다는 것이다. P2P 프로토콜은 콘텐츠를 보유한 사용자가 서버 역할을 분담하기 때문에 수요가 집중될 수록 서비스 품질이 좋아진다. 하지만 P2P 프로토콜은 분산된 서버를 제어할 수 없기 때문에 불법 콘텐츠 분배가 가능하여 상거래 용도로 적합하지 않다. 본 논문에서는 P2P 기반의 모바일 상거래에 적합한 동적 그룹 인증 기법을 제안한다. 제안한 기법은 공통키 생성, 공통키 업데이트, 그룹 서명 및 검증 프로토콜로 구성된다. 그룹을 구성하는 시더의 가입과 탈퇴를 반영할 수 있고, 하이브리드 P2P 기반의 상거래 모델에 적용되어 상거래 서비스는 중앙 서버가 담당하고 콘텐츠는 P2P 기반으로 분배할 수 있다.

의료소비자의 구전정보특성이 구전수용수준과 구전활동에 미치는 영향에 관한 실증적 연구 (A Study on Influences of the Characteristics of Medical Consumers' Words-Transmission Information to its Acceptance Level and its Activities)

  • 강수원;심완섭
    • 한국병원경영학회지
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    • 제3권1호
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    • pp.192-218
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    • 1998
  • This study is the positive one about the influence which the characteristics of medical consumers' perceived words-transmission information exercises on its acceptance level and its activities. The aim of this study was to investigate how the characteristics-reliability of perceived information, its directionity, and its availability-had an influence on the acceptance level and activities of words-transmission information. For the purpose of that aim, the positive research by questionnaire was applied. In addition, to collect necessary data, investigation was performed about 20 days from July 1st, 1938 to July 20th, 1938. As for the respondents' sampling in sample planning, the method of Simple Random Sampling was used laying stress on patients or their responsible person aged over 20s in second and third medical institutions. And the collected sample were 230 people. Of these, However, the number of sample used actually for this study analysis was 211 except 19 people who responded unfaithfully. The analysis of the data collected by the abovesaid investigation used SPSS/PC statistical package. The study result to have proved the hypothesis by experiment is as follows. First, as the result of having analysed the influence relations on the acceptance level and activities of words-transmission information among the factors of reliability about medical consumers' perceived information, I found that 'specialty' had an affirmative effect and there was a significant effect relations. Second, as the result of having made a multi-regression analysis of the effect relations on the acceptance level and activities of words-transmission information of the factors of directionity on medical consumers' perceived information, 'reliablity' was found as having a significant effect on the acceptance of words-transmission information. Third, 'importantness' was revealed as having a significant effect on the words-transmission activities in the acceptance level and activities of words-transmission information among the factors of reliability on medical consumers' perceived information. Fourth. for medical consumers there was a statistical correlation between the acceptance level and activities of words-transmission information. Therefore, words-transmission communication will be very useful for hospital promotion programs having a limited advertising ability in business. Especially, I suggest that a person in charge of his/her hospital marketing should not only excavate a source of words-transmission communication in order to arrive effectively at sampling market, but also use a marketing mix suitable to that The test result shows that the unsatisfied patients over their hospital treatment tend to be more stronger in transmitting words to the other positive minded patients than the satisfied ones. Therefore, all relating representatives in hospital should concentrate their energies on decreasing or eliminating these unwanted results.

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