• 제목/요약/키워드: Steering rate

검색결과 167건 처리시간 0.027초

일본의 타운매니지먼트 운영실태 분석을 통한 민간주도형 도시관리수법 도입방안 연구 - 도쿄, 오사카, 후쿠오카의 타운매니지먼트 지구를 대상으로 - (A Study on Introduction of Privately-led Urban Management System - Based on Analysis of Operation Status of Town Management in Tokyo, Osaka and Fukuoka -)

  • 이슬기;이정형;이운용
    • 대한건축학회논문집:계획계
    • /
    • 제35권3호
    • /
    • pp.67-77
    • /
    • 2019
  • The purpose of this study is to introduce a town management system that utilizes private sectors and public space resources in urban management area. In this study, we are studying 7 town management districts in Japan which have been establishing diverse management systems that are propelled by the private sectors and private fund. We analyzed qualitative characteristics of 7 town management districts by surveying the operating status of organization, financial management and activities. Through the analysis, we clarified their characteristics that are related to establishing background. Also, we suggested conclusions of the study as follows: First of all, it is important to develop a town management method that takes into account the characteristics of the target district in order to overcome the limitation of applying uniform method and increase sustainability and efficiency of privately-led urban management. Second, marketing and promotion are critical strategies in town management since they are satisfying both private and public benefits. The high rate of reinvestment in marketing and promotions shows efforts to maintain the asset value of the private sector and continue to revitalize the city. Finally, in order to carry out urban management with private initiative, it is necessary to establish a working organization capable of realizing the operational direction of the steering committee to secure the executive power.

Recent research activities on hybrid rocket in Japan

  • Harunori, Nagata
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2011년도 제36회 춘계학술대회논문집
    • /
    • pp.1-2
    • /
    • 2011
  • Hybrid rockets have lately attracted attention as a strong candidate of small, low cost, safe and reliable launch vehicles. A significant topic is that the first commercially sponsored space ship, SpaceShipOne vehicle chose a hybrid rocket. The main factors for the choice were safety of operation, system cost, quick turnaround, and thrust termination. In Japan, five universities including Hokkaido University and three private companies organized "Hybrid Rocket Research Group" from 1998 to 2002. Their main purpose was to downsize the cost and scale of rocket experiments. In 2002, UNISEC (University Space Engineering Consortium) and HASTIC (Hokkaido Aerospace Science and Technology Incubation Center) took over the educational and R&D rocket activities respectively and the research group dissolved. In 2008, JAXA/ISAS and eleven universities formed "Hybrid Rocket Research Working Group" as a subcommittee of the Steering Committee for Space Engineering in ISAS. Their goal is to demonstrate technical feasibility of lowcost and high frequency launches of nano/micro satellites into sun-synchronous orbits. Hybrid rockets use a combination of solid and liquid propellants. Usually the fuel is in a solid phase. A serious problem of hybrid rockets is the low regression rate of the solid fuel. In single port hybrids the low regression rate below 1 mm/s causes large L/D exceeding a hundred and small fuel loading ratio falling below 0.3. Multi-port hybrids are a typical solution to solve this problem. However, this solution is not the mainstream in Japan. Another approach is to use high regression rate fuels. For example, a fuel regression rate of 4 mm/s decreases L/D to around 10 and increases the loading ratio to around 0.75. Liquefying fuels such as paraffins are strong candidates for high regression fuels and subject of active research in Japan too. Nakagawa et al. in Tokai University employed EVA (Ethylene Vinyl Acetate) to modify viscosity of paraffin based fuels and investigated the effect of viscosity on regression rates. Wada et al. in Akita University employed LTP (Low melting ThermoPlastic) as another candidate of liquefying fuels and demonstrated high regression rates comparable to paraffin fuels. Hori et al. in JAXA/ISAS employed glycidylazide-poly(ethylene glycol) (GAP-PEG) copolymers as high regression rate fuels and modified the combustion characteristics by changing the PEG mixing ratio. Regression rate improvement by changing internal ballistics is another stream of research. The author proposed a new fuel configuration named "CAMUI" in 1998. CAMUI comes from an abbreviation of "cascaded multistage impinging-jet" meaning the distinctive flow field. A CAMUI type fuel grain consists of several cylindrical fuel blocks with two ports in axial direction. The port alignment shifts 90 degrees with each other to make jets out of ports impinge on the upstream end face of the downstream fuel block, resulting in intense heat transfer to the fuel. Yuasa et al. in Tokyo Metropolitan University employed swirling injection method and improved regression rates more than three times higher. However, regression rate distribution along the axis is not uniform due to the decay of the swirl strength. Aso et al. in Kyushu University employed multi-swirl injection to solve this problem. Combinations of swirling injection and paraffin based fuel have been tried and some results show very high regression rates exceeding ten times of conventional one. High fuel regression rates by new fuel, new internal ballistics, or combination of them require faster fuel-oxidizer mixing to maintain combustion efficiency. Nakagawa et al. succeeded to improve combustion efficiency of a paraffin-based fuel from 77% to 96% by a baffle plate. Another effective approach some researchers are trying is to use an aft-chamber to increase residence time. Better understanding of the new flow fields is necessary to reveal basic mechanisms of regression enhancement. Yuasa et al. visualized the combustion field in a swirling injection type motor. Nakagawa et al. observed boundary layer combustion of wax-based fuels. To understand detailed flow structures in swirling flow type hybrids, Sawada et al. (Tohoku Univ.), Teramoto et al. (Univ. of Tokyo), Shimada et al. (ISAS), and Tsuboi et al. (Kyushu Inst. Tech.) are trying to simulate the flow field numerically. Main challenges are turbulent reaction, stiffness due to low Mach number flow, fuel regression model, and other non-steady phenomena. Oshima et al. in Hokkaido University simulated CAMUI type flow fields and discussed correspondence relation between regression distribution of a burning surface and the vortex structure over the surface.

  • PDF

다중 웨어러블 센서를 활용한 운전자 상태 인식 (Driver's Status Recognition Using Multiple Wearable Sensors)

  • 신의섭;김명국;이창욱;강행봉
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
    • /
    • 제6권6호
    • /
    • pp.271-280
    • /
    • 2017
  • 본 논문에서는 자동차의 안전운전을 위해서 운전자의 생체정보를 수집하여 운전자의 상태에 따라 운전자에게 적절한 경보를 하거나, 직접 자동자를 제어할 수 있는 기반 시스템을 제시하였다. 기존의 운전자 얼굴정보를 촬영하여 정보를 획득하거나, 운전자의 시트나 스티어링 휠에 센서를 장착하여 생제정보를 획득하는 방식이 부정확하거나 단속적인 정보만을 얻을 수 있는데 비하여, 본 논문에서 제시한 웨어러블 장치는 의료장비 수준의 정확도를 얻을 수 있었으며, 지속적으로 높은 정확도의 생체신호를 얻을 수 있었다. 개발된 웨어러블 장치에는 심박, 피부전도도, 피부온도를 측정할 수 있는 센서를 장착하였으며, 자동차에서 발생되는 각종 잡음을 제거할 수 있는 필터 기술을 적용하였고, 가속도센서와 자이로 센서를 장착하여 측정 오차를 제거하는 기술을 적용하였다. 수집된 생체신호를 바탕으로 운전자의 상태를 판별할 수 있는 기준을 제시하였고, 공인인증기관에 의뢰하여 의료수준 정도의 정확성이 있음을 검증하였다. 실험실 시험과 실차 시험을 통하여 개발된 장치가 운전자의 상태를 측정할 수 있는 장치로 활용될 수 있음을 검증하였다.

명량수도 해역에서 항해속력 규제와 선박운용에 관한 연구 (A Study on the Ship's Speed Control and Ship Handling at Myeongnayang Waterway)

  • 김득봉;정재용;박영수
    • 해양환경안전학회지
    • /
    • 제20권2호
    • /
    • pp.193-201
    • /
    • 2014
  • 본 연구는 강조류 해역을 통과하는 선박의 해양사고를 방지하기 위해 안전한 항행속력과 적절한 통과시기를 제시하였다. 이 자료의 해석을 위하여 2010년 7월 12일부터 15일까지 명량수도를 대상으로 통과선박의 AIS 데이터 수집과 2010년 9월 4일 현장조사를 실시하였고, 여기서 수집된 자료를 바탕으로 최소항행속력(minimum navigation speed)과 여유 제어력을 감안한 적정항행속력(optimum navigation speed), 조류속력별 대응타각(respond rudder angle)을 산출하였다. 또한 조위와 조류속력 데이터를 분석해 안전한 통과시기를 제시하였다. 이 연구를 통해 얻은 결과는 다음과 같다. (1) 조류의 유속이 4.4 kn 이상이 되면 선박의 타만으론 자력 조선이 불가능하다. (2) 강한 조류에 의해 발생되는 유압력과 회두모멘트에 대응하기 위해서는 최소항행속력은 조류의 2.3배, 적정항행속력은 조류의 4.0배 이상이어야 한다. (3)사리 기간 중 명량수도 적정 통과 시기는 고 저조시간 1시간 전부터 최소 30분 전까지이며 고 저조가 된 이후 5시간 동안은 4 kn 이상의 유속이 남아있는 시간으로 이 지역 항해를 자제해야 한다.

Tuberculosis Surveillance and Monitoring under the National Public-Private Mix Tuberculosis Control Project in South Korea 2016-2017

  • Min, Jinsoo;Kim, Hyung Woo;Ko, Yousang;Oh, Jee Youn;Kang, Ji Young;Lee, Joosun;Park, Young Joon;Lee, Sung-Soon;Park, Jae Seuk;Kim, Ju Sang
    • Tuberculosis and Respiratory Diseases
    • /
    • 제83권3호
    • /
    • pp.218-227
    • /
    • 2020
  • Background: The national Public-Private Mix (PPM) tuberculosis (TB) control project provides for the comprehensive management of TB patients at private hospitals in South Korea. Surveillance and monitoring of TB under the PPM project are essential toward achieving TB elimination goals. Methods: TB is a nationally notifiable disease in South Korea and is monitored using the surveillance system. The Korea Centers for Disease Control and Prevention quarterly generates monitoring indicators for TB management, used to evaluate activities of the PPM hospitals by the central steering committee of the national PPM TB control project. Based on the notification date, TB patients at PPM hospitals were enrolled in each quarter, forming a cohort, and followed up for at least 12 months to identify treatment outcomes. This report analyzed the dataset of cohorts the first quarter of 2016 through the fourth quarter of 2017. Results: The coverage of sputum, smear, and culture tests among the pulmonary TB cases were 92.8% and 91.5%, respectively. The percentage of positive sputum smear and culture test results were 30.7% and 61.5%, respectively. The coverage of drug susceptibility tests among the culture-confirmed cases was 92.8%. The treatment success rate among the smear-positive drug-susceptible cases was 83.2%. The coverage of latent TB infection treatment among the childhood TB contacts was significantly higher than that among the adult contacts (85.6% vs. 56.0%, p=0.001). Conclusion: This is the first official report to analyze monitoring indicators, describing the current status of the national PPM TB control project. To sustain its effect, strengthening the monitoring and evaluation systems is essential.

방과후학교에서 계약법 적용에 따른 대안 모색 (A Study On The Exploring Alternatives In After-School Program According To The Application Of Contract Law)

  • 정영모
    • 예술인문사회 융합 멀티미디어 논문지
    • /
    • 제6권7호
    • /
    • pp.219-228
    • /
    • 2016
  • 본 연구는 방과후학교 민간위탁의 정책 변화과정을 조사하고, 향후 대안을 제시하는데 목적이 있다. 본 연구를 위해 정책관련 연구 자료와 관련 법규를 문헌조사 하였다. 조사결과 2004년부터 2008년은 교육부에서 방과후학교 운영계획을 수립하였으나 학교운영위원회의 심의(자문)를 통해 단위학교의 자율로 민간위탁이 진행되었고, 2008년부터 2015년은 교육부와 시도교육청에서 공동으로 제작한 '방과후학교 운영 가이드라인'에 제시된 표준화된 절차를 따르고 있었으며, 2016년 이후에는 방과후학교 민간위탁 시 계약법을 적용하도록 하는 등 정책 변화가 있었다. 2016년 이후의 정책 변화는 방과후학교 민간위탁의 투명성 확보 필요성과 함께 방과후학교 민간위탁 계약규모가 커지면서 계약법을 준수해야 하는 법적 필요성에 기인한다. 하지만 최저가 입찰방식으로 인해 방과후학교 교육의 질이 떨어질 수밖에 없다는 우려의 목소리도 함께 제기되고 있다. 정부에서는 기초금액에서 일정비율 이상을 인건비로 지급하도록 하여 지나친 가격경쟁을 방지하는 대안을 제시하였지만, 본 논문에서는 보다 근본적인 해결 방안으로 방과후학교 교육활동 및 시도의 특수성을 담아내는 시도의 조례를 제정하는 방안을 제시하였다.

추후관리가 필요한 만성질환 퇴원환자 가정간호 시범사업 운영 연구 (An Operations Study on a Home Health Nursing Demonstration Program for the Patients Discharged with Chronic Residual Health Care Problems)

  • 홍여신;이은옥;이소우;김매자;홍경자;서문자;이영자;박정호;송미순
    • 대한간호학회지
    • /
    • 제20권2호
    • /
    • pp.227-248
    • /
    • 1990
  • The study was conceived in relation to a concern over the growing gap between the needs of chronic patients and the availability of care from the current health care system in Korea. Patients with agonizing chronic pain, discomfort, despair and disability are left with helplessly unprepared families with little help from the acute care oriented health care system after discharge from hospital. There is a great need for the development of an alternative means of quality care that is economically feasible and culturally adaptible to our society. Thus, the study was designed to demonstrate the effectiveness of home heath care as an alternative to bridge the existing gap between the patients' needs and the current practice of health care. The study specifically purports to test the effects of home care on health expenditure, readmission, job retention, compliance to health care regime, general conditions, complications, and self-care knowledge and practices. The study was guided by the operations research method advocated by the Primary Health Care Operations Research Institute(PRICOR) which constitutes 3 stages of research : namely, problem analysis solution development, and solution validation. The first step in the operations research was field preparation to develop the necessary consensus and cooperation. This was done through the formation of a consulting body at the hospital and a steering committee among the researchers. For the stage of problem analysis, the Annual Report of Seoul National University Hospital and the patients records for last 5 years were reviewed and selective patient interviews were conducted to find out the magnitude of chronic health problems and areas of unmect health care needs to finally decide on the kinds of health problems to study. On the basis of problem analysis, the solution development stage was devoted to home care program development asa solution alternative. Assessment tools, teaching guidelines and care protocols were developed and tested for their validity. The final stage was the stage of experimentation and evaluation. Patients with liver diseases, hemiplegic and diabetic conditions were selected as study samples. Discharge evaluation, follow up home care, measurement and evaluation were carried out according to the protocols of care and measurement plan for each patient for the period of 6 months after discharge. The study was carried out for the period from Jan. 1987 to Dec. 1989. The following are the results of the study presented according to the hypotheses set forth for the study ; 1. Total expenditures for the period of study were not reduced for the experimental group, however, since the cost per hospital visit is about 4 times as great as the cost per home visit, the effect of cost saving by home care will become a reality as home care replaces part of the hospital visits. 2. The effect on the rate of readmission and job retention was found to be statistically nonsignificant though the number of readmission was less among the experimental group receiving home care. 3. The effect on compliance to the health care regime was found to be statistically significant at the 5% level for hepatopathic and diabetic patients. 4. Education on diet, rest and excise, and medication through home care had an effect on improved liver function test scores, prevention of complications and self - care knowledge in hepatopathic patients at a statistically significant level. 5. In hemiplegic patient, home care had an effect on increased grasping power at a significant level. However. there was no significant difference between the experimental and control groups in the level of compliane, prevention of complications or in self-care practices. 6. In diabetic patients, there was no difference between the experimental and control groups in scores of laboratory tests, appearance of complications, and self-care knowledge or self -care practices. The above findings indicate that a home care program instituted for such short term as 6 months period could not totally demonstrate its effectiveness at a statistically significant level by quantitative analysis however, what was shown in part in this analysis, and in the continuous consultation sought by those who had been in the experimental group, is that home health care has a great potential in retarding or preventing pathological progress, facilitating rehabilitative and productive life, and improving quality of life by adding comfort, confidence and strength to patients and their families. For the further studies of this kind with chronic patients it is recommended that a sample of newly diagnosed patients be followed up for a longer period of time with more frequent observations to demonstrate a more dear- cut picture of the effectiveness of home care.

  • PDF