• Title/Summary/Keyword: Self-sustaining System

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Seismic Performance Evaluation of Dry Precast Concrete Beam-Column Connections with Special Moment Frame Details (특수모멘트골조 상세를 갖는 건식 프리캐스트 콘크리트 보-기둥 접합부의 내진성능평가)

  • Kim, Seon Hoon;Lee, Deuck Hang;Kim, Yong Kyeom;Lee, Sang Won;Yeo, Un Yong;Park, Jung Eun
    • Journal of the Earthquake Engineering Society of Korea
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    • v.27 no.5
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    • pp.203-211
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    • 2023
  • For fast-built and safe precast concrete (PC) construction, the dry mechanical splicing method is a critical technique that enables a self-sustaining system (SSS) during construction with no temporary support and minimizes onsite jobs. However, due to limited experimental evidence, traditional wet splicing methods are still dominantly adopted in the domestic precast industry. For PC beam-column connections, the current design code requires achieving emulative connection performances and corresponding structural integrity to be comparable with typical reinforced concrete (RC) systems with monolithic connections. To this end, this study conducted the standard material tests on mechanical splices to check their satisfactory performance as the Type 2 mechanical splice specified in the ACI 318 code. Two PC beam-column connection specimens with dry mechanical splices and an RC control specimen as the special moment frame were subsequently fabricated and tested under lateral reversed cyclic loadings. Test results showed that the seismic performances of all the PC specimens were fully comparable to the RC specimen in terms of strength, stiffness, energy dissipation, drift capacity, and failure mode, and their hysteresis responses showed a mitigated pinching effect compared to the control RC specimen. The seismic performances of the PC and RC specimens were evaluated quantitatively based on the ACI 374 report, and it appeared that all the test specimens fully satisfied the seismic performance criteria as a code-compliant special moment frame system.

Seismic Performance Evaluation of Dry Precast Concrete Beam-Column Connections With Intermediate Moment Frame Details (중간모멘트골조 상세를 갖는 건식 프리캐스트 콘크리트 보-기둥 접합부의 내진성능평가)

  • Kim, Seon Hoon;Cho, Jong;Oh, Hyo Keun;Choi, Seok Dong;Yeo, Un Yong;Lee, Deuck Hang
    • Journal of the Earthquake Engineering Society of Korea
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    • v.27 no.3
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    • pp.129-137
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    • 2023
  • This study presents a dry precast concrete (PC) beam-column connection, and its target seismic performance level is set to be emulative to the reinforced concrete (RC) intermediate moment resisting frame system specified in ACI 318 and ASCE 7. The key features include self-sustaining ability during construction with the dry mechanical splicing method, enabling emulative connection performances and better constructability. Test specimens with code-compliant seismic details were fabricated and tested under reversed cyclic loading, which included a PC beam-column connection specimen with dry connections and an RC control specimen. The test results showed that all the specimens failed in a similar failure mode due to plastic deformations in beam members, while the hysteretic response curve of the PC specimen showed comparable and emulative performances compared to the RC specimen. Seismic performance evaluation was quantitatively addressed, and on this basis, it confirmed that the presented system can fully satisfy all the required performance for the intermediate RC moment resisting frame.

Legislative Approaches to Terminal Care Issue in the U.S.A. - Acts on Terminal Health-Care Decision (말기의료에 관한 미국 법제의 연구 - 말기의료결정 제도를 중심으로)

  • Suk, HeeTae
    • The Korean Society of Law and Medicine
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    • v.14 no.1
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    • pp.355-401
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    • 2013
  • The first legislation for terminal health-care decision was California's Natural Death Act (NDA) of 1976 that permitted any adult person to execute a directive directing the withholding or withdrawal of life-sustaining procedures. Advance directive legislation has subsequently progressed on a state-by-state basis. By 1992, all 50 states, as well as the District of Columbia, had passed legislation to legalize some form of advance directive. This state legislation, however, has resulted in an often fragmented, incomplete, and sometimes inconsistent set of rules. Statutes enacted within a state often conflict and conflicts between statutes of different states are common. In an increasingly mobile society where an advance health-care directive given in one state must frequently be implemented in another, there is a need for greater uniformity. In 1993, the Uniform Law Commissioners approved the Uniform Health-Care Decisions Act (UHCDA) in order to bring order to the existing chaos. Unfortunately, the Commissioners waited too long to act. By the time the UHCDA was approved, nearly all states had passed legislation governing advance directives. Consequently, the UHCDA has achieved only a limited success, picking up but one or two enactments a year. The UHCDA is currently in effect in around 10 states: Alabama, Alaska, California, Delaware, Hawaii, Kansas, Maine, Mississippi, New Mexico, Tennessee, Wyoming. In these states the previous laws related to the subjects have been all repealed. The overall objective of the UHCDA is to encourage the making and enforcement of advance health care directives including living will or individual instruction, power of health-care attorney and to provide a means for making health care decisions for those who have failed to plan. The U. S. House of Representatives in 1991 enacted the Patient Self-Determination Act (PSDA). The Act stipulates that all hospitals receiving Medicaid or Medicare reimbursement must ascertain whether patients have or wish to have advance directives. The Patient Self- Determination Act does not create or legalize advance directives; rather it validates their existence in each of the states. Now in America, terminal health-care decision or advance directive for health care is common and universal system. The problem, however, is how to let more people use these good tools to make their lives more beautiful and honorable.

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Empirical Research for Activating the Public Health on Regional Medical Center of Local Government (지방자치단체 지방의료원의 운영 활성화를 위한 실증적 연구)

  • Lee, Shin-Suk;Park, Sang-Moo;Sim, Moon-Bo
    • The Journal of the Korea Contents Association
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    • v.12 no.10
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    • pp.178-194
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    • 2012
  • Regional medical center, this country's public health researchers to activate discussion about public health nature of publicness and Regional medical center to identify actual conditions of the present analysis of previous studies based on the experience of researchers and policy factors, environmental factors, financial factors, and self-sustaining factors affecting the activation of the public health by assuming that the four provinces, Chungnam Regional Medical Center conducted the survey to target four factors through empirical analysis and 40 kinds of relationships with sub-variables hypothesis. To empirical analysis as a background element present hypotheses and research model setting, study population and method of analysis of the set, factor analysis and reliability, validity analysis conducted, and Windows 7 operating system SPSS 19.0 analysis tool for Regional Medical Center enable the public health was to investigate the relationship between factors and variables, PLS 2.0 as an analytical tool to test the hypothesis through the analysis of the model was used.

The Daily Life Experiences of Community Dwelling People with Mental Disabilities (재가 정신장애인의 일상생활경험)

  • Jun, Won Hee;Choi, Eun Joung;Cho, Hyun Mee
    • Research in Community and Public Health Nursing
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    • v.31 no.3
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    • pp.244-255
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    • 2020
  • Purpose: As the daily life experiences of community-dwelling people with mental disabilities are closely correlated to mental health recovery, this study aimed to analyze their daily life experiences in depth to determine their significance. Method: Participants included eight community-dwelling people with mental disabilities. A total of 12 in-depth interviews were conducted once or twice per participant. The collected data were analyzed using the phenomenological analysis method described by Giorgi. Results: The daily life experiences of community-dwelling people with mental disabilities were categorized into the following four components: "encountering shocking reality in the outside world", "life tied down by the mental illness", "happiness and gratefulness encountered in daily life", and "wishing for a change and self-sustaining life". Conclusion: This study found that the recovery and welfare of community-dwelling people with mental disabilities were promoted and that these patients made necessary efforts to become a member of the local community. These findings could be used as a reference for establishing social welfare policies which enable people with mental disabilities to participate as functioning members of the community that facilitate the prevention of relapse, to promote their integration into the community. Furthermore, the present results will contribute to the development of nursing intervention programs to promote recovery and prevent relapse, to ultimately establish a mental health management system.

A Study on the general population's attitude and related factor on the continuity of medical care (의료 지속성에 대한 일반인들의 태도 및 관련요인 - 사무직 직원들을 대상으로 -)

  • Jo, Heui-Sug;Jeong, Heon-Jae;Lee, Sun-Hee
    • Korea Journal of Hospital Management
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    • v.9 no.3
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    • pp.1-17
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    • 2004
  • This study is aimed to assess the general population's attitude toward the continuity of medical care and its related factors. Self administered questionnaire was performed on the 1,120 office workers in the C city, Gang-won province. The questionnaire included the attitude of the continuity of medical institute, the intention of medical service use on a given case, and the variables of the related factors. 58.8% of the total respondents agreed to sustaining treatment without changing medical institutes; on the other hand, 41.2% showed negative attitude. In case that a patient would gain a recommendation of a surgery, hospitalization, or a specific examination, the total respondents' 84.9%, 61.8%, and 50.8% of each recommended situation said that they would visit another doctor and gain a diagnosis. As a result of multiple logistic analysis of determinant factor on continuity, reliability of doctors was statistically significant factor. In order to reduce wastefully used medical resources and offer well-qualified medical service, a system of second opinion among peer group or beforehand agreement could be possibly adopted. In addition, improving the image and reliability of a doctor could be an important factor to make better the behavior of medical service shopping; therefore, an effort to improve the relationship between a doctor and a patient, and restore the reliability of doctors should be paralleled.

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Milk Production of Dairy Cattle from Organic Farming in Germany and Development Trends in Korea (독일의 유기축산에 의한 젖소사육 현황과 무리나라의 발전 방향)

  • 류종원
    • Journal of Animal Environmental Science
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    • v.8 no.1
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    • pp.25-34
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    • 2002
  • In view of increasing environmental pollution, the organic farming in animal production is becoming increasingly urgent. The problems of veterinary medicine have not diminished through the most dangerous epidemic diseases. Organic farming attempts to function in harmony with the environment. The first criterion of the organic farm is that the animal must be self-sustaining. Their food must be produced to a large extent on the farm. The position of ruminants in biological systems is determined by the fact that this group of farm animals is provided with a digestive system which optimizes the utilization of the products of gut microfloral fermentation. The cattle do not require large amounts of concentrate feeling nor gross ugly farm building for intensive rearing. The economic profitability of a cow depends. on the first instance, on the level of milk production and the number of lactations. The length of life is an important factor since the tilde to maturing is relatively high in a cow. The result is that dairy cows in organic farming have greater length of live, and produce more milk in their life time than the shorter lived high input cow. This paper. therefore, discussed the problems of modern cattle farming and development trends of organic farming in Germany and Korea.

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Size Tailored Nanoparticles of ZrN Prepared by Single-Step Exothermic Chemical Route

  • Lee, Sang-Ki;Park, Kyung-Tae;Ryu, Hong-Youl;Nersisyan, Hayk H.;Lee, Kap-Ho;Lee, Jong-Hyeon
    • Korean Journal of Materials Research
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    • v.22 no.5
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    • pp.243-248
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    • 2012
  • ZrN nanoparticles were prepared by an exothermic reduction of $ZrCl_4$ with $NaN_3$ in the presence of NaCl flux in a nitrogen atmosphere. Using a solid-state combustion approach, we have demonstrated that the zirconium nitride nanoparticles synthesis process can be completed in only several minutes compared with a few hours for previous synthesis approaches. The chemistry of the combustion process is not complex and is based on a metathesis reaction between $ZrCl_4$ and $NaN_3$. Because of the low melting and boiling points of the raw materials it was possible to synthesize the ZrN phase at low combustion temperatures. It was shown that the combustion temperature and the size of the particles can be readily controlled by tuning the concentration of the NaCl flux. The results show that an increase in the NaCl concentration (from 2 to 13 M) results in a temperature decrease from 1280 to $750^{\circ}C$. ZrN nanoparticles have a high surface area (50-70 $m^2/g$), narrow pore size distribution, and nano-particle size between 10 and 30 nm. The activation energy, which can be extracted from the experimental combustion temperature data, is: E = 20 kcal/mol. The method reported here is self-sustaining, rapid, and can be scaled up for a large scale production of a transition metal nitride nanoparticle system (TiN, TaN, HfN, etc.) with suitable halide salts and alkali metal azide.

A Survey on RF Energy Harvesting System with High Efficiency RF-DC Converters

  • Khan, Danial;Basim, Muhammad;Ali, Imran;Pu, YoungGun;Hwang, Keum Cheol;Yang, Youngoo;Kim, Dong In;Lee, Kang-Yoon
    • Journal of Semiconductor Engineering
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    • v.1 no.1
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    • pp.13-30
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    • 2020
  • Radio frequency (RF) energy harvesting technology have become a reliable and promising alternative to extend the lifetime of power-constrained wireless networks by eliminating the need for batteries. This emerging technology enables the low-power wireless devices to be self-sustaining and eco-friendly by scavenging RF energy from ambient environment or dedicated energy sources. These attributes make RF energy harvesting technology feasible and attractive to an extended range of applications. However, despite being the most reliable energy harvesting technology, there are several challenges (especially power conversion efficiency, output DC voltage and sensitivity) poised for the implementation of RF energy harvesting systems. In this article, a detailed literature on RF energy harvesting technology has been surveyed to provide guidance for RF energy harvesters design. Since signal strength of the received RF power is limited and weak, high efficiency state-of-the-art RF energy harvesters are required to design for providing sufficient DC supply voltage to wireless networks. Therefore, various designs and their trade-offs with comprehensive analysis for RF energy harvesters have been discussed. This paper can serve as a good reference for the researchers to catch new research topics in the field of RF energy harvesting.

A Design and Implementation of Chick Incubation System Based on IoT

  • Sejong Lee;Sol Lee
    • Journal of the Korea Society of Computer and Information
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    • v.29 no.9
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    • pp.179-186
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    • 2024
  • In this paper, we design and implement an Internet of Things (IoT)-based chick incubation system. The system consists of three key components: the IoT incubator, the IoT server system, and the smartphone application. The IoT incubator is composed of an Arduino board, temperature and humidity sensors, a temperature and humidity controller, a ventilation controller, and an egg turning controller. The temperature and humidity sensors measure the temperature and humidity inside the IoT incubator and send the data to the temperature and humidity controller on the Arduino board. Additionally, it provides the function of transmitting temperature, humidity, and control history data to the IoT server via WiFi. It also offers automatic control of ventilation, egg turning, and temperature and humidity on a daily basis. The IoT server system receives data from the incubator, stores it in a database, and provides query data upon request from the smartphone. The smartphone application retrieves historical data through the server and monitors the temperature and humidity data of the IoT incubator in real-time, controlling the IoT incubator to ensure that the set temperature and humidity ranges are maintained. If the temperature and humidity data deviate from the set ranges, it sends alarms and emergency messages to the user. The IoT-based chick incubation system developed in this paper is a low-cost model due to its reduced manufacturing cost, making it highly beneficial for self-sustaining poultry farms.