• Title/Summary/Keyword: long-life time

Search Result 1,596, Processing Time 0.029 seconds

Low price type inspection and monitoring system of lithium ion batteries for hybrid vessels (하이브리드 선박용 리튬 배터리의 저가형 감시시스템 구현)

  • Kwon, Hyuk-joo;Kim, Min-kwon;Lee, Sung-geun
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.40 no.1
    • /
    • pp.28-33
    • /
    • 2016
  • Batteries are used for main power engine in the fields such as mobiles, electric vehicles and unmanned submarines, for starter and lamp driver in general automotive, for emergency electric source in ship. These days, lead-acid and the lithium ion batteries are increasingly used in the fields of the secondary battery, and the lead-acid battery has a low price and safety comparatively, The lithium ion battery has a high energy density, excellent output characteristics and long life, whereas it has the risk of explosion by reacting with moisture in the air. But Recently, due to the development of waterproof, fireproof, dustproof technology, lithium batteries are widely used, particularly, because their usages are getting wider enough to be used as a power source for hybrid ship and electric propulsion ship, it is necessary to manage more strictly. Hybrid ship has power supply units connected to the packets to produce more than 500kWh large power source, and therefore, A number of the communication modules and wires need to implement the wire inspection and monitor system(WIIMS) that allows monitoring server to transmit detecting voltage, current and temperature data, which is required for the management of the batteries. This paper implements a low price type wireless inspection and monitoring system(WILIMS) of the lithium ion battery for hybrid vessels using BLE wireless communication modules and power line modem( PLM), which have the advantages of low price, no electric lines compared to serial communication inspection systems(SCIS). There are state of charge(SOC), state of health(SOH) in inspection parts of batteries, and proposed system will be able to prevent safety accidents because it allows us to predict life time and make a preventive maintenance by checking them at regular intervals.

Medical Practitioners' Reasons for Practice in Great Gity(Taegu) (개원의의 대도시 개원 이유 : 대구시 개원의를 중심으로)

  • Kam, Sin;Chun, Byung-Yeol;Park, Jae-Yong;Yeh, Min-Hae;Song, Dal-Hyo
    • Health Policy and Management
    • /
    • v.2 no.1
    • /
    • pp.17-41
    • /
    • 1992
  • During the month of October, 1990, 676 practicing physicians in Taegu City were surveyed by mail questionnaires about their general characteristics and the reasons why they chose Taegu as a practice location and 331 out of them responded completely. Collected data were analyzed to provide basic reference data for future health manpower policy which intends to solve the problem of geographical maldistribution of physicians, The major findings are as follows: For the question asking why Taegu area is favored, following lists are as the order of their magnitude of the reasons replied by more than 20% of the respondents: 1) Taegu is a foundation of life until now(81.3%) 2) Better educational environments are available for their offsprings(73.7%) 3) They can have intimate relationship with acquaintances or friends sharing same or similar interests(61.0%) 4) Due to characteristics of their specialty, metropolitan seems to fit better(52.0%), 5) They graduated from the medical school in Taegu(49.8%) 6) Never thought of selecting practice location in other area than Taegu without any specific reasons(45.9%) 7) Intelligent communications are available with other physicians(39.9%) 8) More opportunities to participate in social life, such as medical, or alumni association etc., can be given(33.2%) 9) No specific knowledge or relationships with other area are available(32.6%) 10) They finished internship or residency training in Taegu area(31.4%) 11) Facilitation of transferring patients including emergent patients can be obtained (30.8%) 12) Continuing medical educational programs are available(29.9%) 13) Sufficient medical demands are provided because of the large population(28.1%) 14) More chances to be grown up as a medical professionals can be achieved(25.7%) 15) More leizure time can be utilized for cultural activities(23.9%) 16) They had experiences to work in hospitals or facilities in Taegu area(23.3%) 17) Medical facilities of fellow physicians or alumni can be used(20.5%) In addition, 37% of female physicians answered that their spouse strongly influenced them to choose Taegu, and 33.3% of physicians with age of thirty replied that parents did so. Physicians of specialty in radiology, clinical pathology, anatomical pathology, and anesthesiology considered that patients from other hospitals and medical facilities would be referred often to them and that less competition seemed to be expected in their specialty (30.8%). In contrast, general practitioners anticipated that larger population would increase the medical demand(62.5%). 28.6% of medical practitioners who graduated medical schools in other are than Taegu and 22.0% of medical practitioners who were trained in hospitals of other area than Taegu were influenced to choose Taegu by their spouses. In consideration of above findings, we may conclude that long term and rational manpower policies should be implemented to solve the problem of geographical maldistribution of physicians as well as short term physician-inducing policies, and they have to be incorporated with equitable community development.

  • PDF

A Case Study on Students' Mathematical Concepts of Algebra, Connections and Attitudes toward Mathematics in a CAS Environment (CAS 그래핑 계산기를 활용한 수학 수업에 관한 사례 연구)

  • Park, Hui-Jeong;Kim, Kyung-Mi;Whang, Woo-Hyung
    • Communications of Mathematical Education
    • /
    • v.25 no.2
    • /
    • pp.403-430
    • /
    • 2011
  • The purpose of the study was to investigate how the use of graphing calculators influence on forming students' mathematical concept of algebra, students' mathematical connection, and attitude toward mathematics. First, graphing calculators give instant feedback to students as they make students compare their written answers with the results, which helps students learn equations and linear inequalities for themselves. In respect of quadratic inequalities they help students to correct wrong concepts and understand fundamental concepts, and with regard to functions students can draw graphs more easily using graphing calculators, which means that the difficulty of drawing graphs can not be hindrance to student's learning functions. Moreover students could understand functions intuitively by using graphing calculators and explored math problems volunteerly. As a result, students were able to perceive faster the concepts of functions that they considered difficult and remain the concepts in their mind for a long time. Second, most of students could not think of connection among equations, equalities and functions. However, they could understand the connection among equations, equalities and functions more easily. Additionally students could focus on changing the real life into the algebraic expression by modeling without the fear of calculating, which made students relieve the burden of calculating and realize the usefulness of mathematics through the experience of solving the real-life problems. Third, we identified the change of six students' attitude through preliminary and an ex post facto attitude test. Five of six students came to have positive attitude toward mathematics, but only one student came to have negative attitude. However, all of the students showed positive attitude toward using graphing calculators in math class. That's because they could have more interest in mathematics by the strengthened and visualization of graphing calculators which helped them understand difficult algebraic concepts, which gave them a sense of achievement. Also, students could relieve the burden of calculating and have confidence. In a conclusion, using graphing calculators in algebra and function class has many advantages : formulating mathematics concepts, mathematical connection, and enhancing positive attitude toward mathematics. Therefore we need more research of the effect of using calculators, practical classroom materials, instruction models and assessment tools for graphing calculators. Lastly We need to make the classroom environment more adequate for using graphing calculators in math classes.

The Method of Participatory Government to Introduce the System of Autonomous Police (참여정부의 자치경찰제 도입방안)

  • Jung, Jin-Hwan
    • Korean Security Journal
    • /
    • no.10
    • /
    • pp.355-385
    • /
    • 2005
  • As the system of autonomous police that has been debated for long time is fixed to be introduced by the program of participatory government, this treatise intends to analyze main contents and review controversial items in order to present supplementary measures. The program of participatory government to introduce autonomous police in Korea focuses on converting the autonomous police of Korea from centralized police administration in order to provide 'customized security service' that is appropriate to the regional environment. Thus, if relevant city, county or district considers that it is required to introduce the system autonomous police, the assembly may enforce the decision by enacting ordinance. For enforcement, organization in the unit of section will be established in the line of mayor, county headman and district office. The main role will be security service that is closely related to the life of inhabitants such as crime prevention, patrol, traffic crackdown, etc. as well as public health, sanitation and environmental control which are being performed by autonomous organization at present. However some expected controversial items may be summarized in the following 3 points on the premise of accepting the program of government. First, the point at issue related to the basic function of police. The basic function of police is generally understood as order keeping function such as anterior and preventive job and law enforcing function such as posterior and suppressing job. By the way, the program of government does not endow the autonomous police with investigation right for general crime, thereby raising the controversy that our autonomous police is nothing but the assistant of police. Furthermore, the present national police also expresses its dissatisfaction to the transfer of authority. Second, the issue of balance of security service between self-governing bodies may be raised. The security environment is different between self-governing bodies and thus demand of security is different. Therefore, the security service of autonomous police will reveal difference in qualitative aspect for each self-governing body. Moreover, it can be easily anticipated that the quality of security service may be different as per the financial independence degree. Third, the point at issue anticipated with the operation funded by the budget of self-governing body. As autonomous police is operated by the budget of self-governing body, the following problems may be raised; (1) since police administration is subordinated to general administration, the concentration may be weakened (2) the cooperation between policy agencies may be impeded (3) owing to the difficult in possessing spare police, the mobility of police may be somewhat reduced.

  • PDF

Effects of Postharvest 1-MCP Treatment, Storage Method, and Shelf Temperature on Quality Changes of 'Gamhong' Apples during Export Simulation (수확후 1-MCP 처리, 저장 방법 및 현지 유통온도가 모의수출 '감홍' 사과의 품질에 미치는 영향 분석)

  • Park, Youn-Moon;Yoon, Tae-Myung
    • Horticultural Science & Technology
    • /
    • v.30 no.6
    • /
    • pp.725-733
    • /
    • 2012
  • Effects of postharvest 1-methylcyclopropene (1-MCP) treatment, controlled atmosphere (CA) storage, and shelf temperature on quality of 'Gamhong' apples were analyzed during export simulation. Fruits were harvested at the optimum maturity for long-term storage, treated with $1{\mu}L{\cdot}L^{-1}$ 1-MCP for 16 hours, and then stored for 6 months under air and CA conditions at $0^{\circ}C$. Poststorage export procedure was performed by applying additional 2-week refrigerated storage and 7-day shelf-life test at 7 and $20^{\circ}C$, which simulated container shipment and local distribution, respectively. After storage and during export simulation, rates of respiration and ethylene evolution were significantly lower in 1-MCP treated and CA-stored apples. For the reduction of respiration, CA storage was more effective than 1-MCP treatment. Soluble solids content was maintained higher in 1-MCP treated apples, while titratable acidity was maintained better both in the 1-MCP treated and CA-stored apples. Effects of 1-MCP treatment and CA storage were highly significant in maintaining flesh firmness and sensory texture ratings. Additive effects from combined application of 1-MCP treatment and CA storage were occasionally observed. Shelf temperature during the local distribution simulation seemed not to significantly influence quality changes only showing limited effects on flesh firmness. Overall results suggest that storage potential of 'Gamhong' apples is shorter than 4 months in control fruit under refrigerated air conditions, whereas the potential can be extended to longer than 6 months by 1-MCP treatment and CA storage. Postharvest program should be provided considering the time of export, i.e. period of storage, and duration of local distribution.

Multiplification of the Reality in Contemporary Sculpture (현대조각에 있어서 실재의 다중화)

  • You, Jae-Heung
    • Journal of Science of Art and Design
    • /
    • v.12
    • /
    • pp.65-96
    • /
    • 2007
  • Today, the modern art is extremely diverse. It is denying its own boundary through chaos, extreme, abjection. In fact the diversity of the modern art can be best described as questioning and challenging to the essence of the reality, rather than the artistic pursuit of the beauties. The pursuit of the reality has been a long lasting discourse since the ancient. Through the history, the reality (referent) and representation (image) has been complementing and disposing each other in a relationship of a meaningful construction until the modern times. The limit of modernistic self-reference and the emergence of the figure leads to the emergence of Post-modernism in a trend of experimenting new visual arts. The return to the figure is clearly distinguished from existing representation's system and it brought new meanings to approaches and interpretations of the reality. In the case of Pop arts of 1960's and the following the modern sculptures, which is covered by this thesis, I put an emphasis on the diversification of those via changed strategies on the reality. In a situation where the reality is dictated by signified, the modern arts can no longer stay on a classic concept of representation, rather it pursuits new system and diverse strategies. I provide three types of strategic characters of the reality and the diversification of reality: the transition of the reality. These three types can be used as a frame work, which is supporting new aspects of the modern arts in reflecting on existing system. Therefore, the reason of categorizing is to distinguish modernistic arts and post modernistic arts, and to propose new post-modernistic discourses. Adapting J.F, Lyotard's view, absence is used to trace down the diversification of the reality thorough the sublime on the deconstruction of the mega discourses and the relationship of representation. Based on H. Faster's theory of the appropriation, the appropriation is used to exemplify the strategies of visual arts are in variations and being delayed. Lastly, in the transition, J. Baudrilliard's simulacre is used in terms of the concept of post modernistic representation. Based on the core of his theories, the deconstruction of existing concepts and simulation as the post modernistic representation, and the world of hyperreality based on simulacre are explained. These allows us to deny that representation is the expression of reality through mimesis. My aim is to work on the definition of the arts and representation in the modern era, and go further from there in order to clarify meaning and extension of the modern sculptures. Now two artists are reviewed based on their own art works: George Seagal; Jeff Koons. They are selected among numerous artists from the Post Modern era. Epic contents and emphasis on daily life of Seagal's works show good examples to artists from Pop Arts and following time period and may have served as a start point for Postmodernism. Indeed, he tried to show a newly defined relationship between art works and daily life experience. On the other hand, J.Koons used the strategies of fabrication and appropriation, which shows characteristics of the postmodernism. Through his four individual exhibitions, he shows the diversification of the reality based on art works as fetishistic merchandises, and newly defined concept of Ready-made since M Duchamp. Lastly, the diversification of the reality is analyzed again in context of my art works. I focused on the return to the figure among a variety of trends of late 20 th century modern sculpture. It showed the post modernistic point of view on the reality. Post modernistic diversified strategies are adopted as a method of distinguishing each art works via the diversification of the reality. This is the result of contemporary social and cultural situations.

  • PDF

Study on Fire Hazard Analysis along with Heater Use in the Public Use Facility Traditional Market in Winter (겨울철 다중이용시설인 전통재래시장 난방기구 사용에 따른 화재 위험성 분석에 관한 연구)

  • Ko, Jaesun
    • Journal of the Society of Disaster Information
    • /
    • v.10 no.4
    • /
    • pp.583-597
    • /
    • 2014
  • Fire caused by heater has various causes as many as the types of heater. also, lots of damage of human life and property loss are caused, since annually continuous fire accident by heater in traditional market is frequently occurring. There are not many cases of fire due to heater in most of residential facilities such as general house, apartments, etc., because they are supplied with heating boiler, however the restaurant, store and office of the market, sports center, factory, workplace, etc. still use heater, e.g. oilstove, electric heater, etc., so that they are exposed to fire hazard. Also, when investigating the number of fire due to heater, it was analyzed to occur in order of home boiler, charcoal stove, oilstove, gas heater/stove, electric stove/heater, the number of fire per human life damage was analyzed in order of gas heater/stove, oil heater/stove, electric heater/stove, briquette/coal heater. Also, gas and oil related heater were analyzed to have low frequency, however, with high fire intensity. Therefore, this research aimed at considering more scientific fire inspection and identification approach by reenacting and reviewing fire outbreak possibility caused by combustibles' contact and conductivity under the normal condition and abnormal condition in respect of ignition hazard, i.e. minimum ignition temperature, carbonization degree and heat flux along with it, due to oilstove and electric stove, which are still frequently used in public use facility, traditional market, and, of which actual fire occurrence is the most frequent. As the result of reenact test, ignition hazard appeared very small, as long as enough heat storage condition is not made in both test objects(oilstove/electric stove), however carbonization condition was analyzed to be proceeded per each part respectively. Eventually, transition to fire is the ignition due to heat storage, so that it was analyzed to ignite when minimum heat storage temperature condition of fire place is over $500^{\circ}C$. Particularly, in case of quartz pipe, the heating element of electric stove, it is rapidly heated over the temperature of $600^{\circ}C$ within the shortest time(10sec), so that the heat flux of this appears 6.26kW/m2, which was analyzed to result in damage of thermal PVC cable and second-degree burn in human body. Also, the researcher recognized that the temperature change along with Geometric View Factor and Fire Load, which display decrease of heat, are also important variables to be considered, along with distance change besides temperature condition. Therefore, the researcher considers that a manual of careful fire inspection and identification on this is necessary, also, expects that scientific and rational efforts of this research can contribute to establish manual composition and theoretical basis on henceforth fire inspection and identification.

A Study on the Current Status of Health Screening and the Health Type(Physical Activity, and etc) of the Disabled by Using the Statistics of Health Insurance Corporation (건강보험공단 통계를 이용한 장애인의 건강검진 현황 및 건강형태(신체활동 등)에 대한 소고)

  • Kim, Seck-Jin;Jung, Jin-Sung
    • Journal of the Korean Applied Science and Technology
    • /
    • v.35 no.2
    • /
    • pp.433-444
    • /
    • 2018
  • This study aims to examine the screening rate of health screening of the disabled by screening the data of disability and health statistics of the National Health Insurance Corporation, to suggest the problems of health examination and the future improvement measures, and also to review the type of health management of the disabled based on the results of health examination interview. As people with limited daily life or social life for a long time because of their physical/psychological disabilities in accordance with the Article2 of , out of 2,479,080 registered people with disabilities on the basis of December 31st 2015, the research subjects were limited to people with disabilities who participated in the health screening and health type for presenting the opinions about policies. In conclusion, regarding the health screening for the disabled, first, it would be necessary to collect the opinions from people with disabilities in order to prepare the health screening service suitable for them. Second, it would be needed to develop the health screening items for each type of disability and severity. Third, it would be necessary to consider the medical equipments and amenities of health examination for the disabled. Fourth, there should be the securement of manpower and education for service providers. Fifth, the mobility right of the disabled should be secured. Regarding the health type of the disabled, first, the expert consultative group in each area should be composed for the health enhancement of the disabled. Second, it would be necessary to screening the current status of health enhancement programs for the disabled and operating facilities. Third, the Central Health Medical Center for the Disabled, shown in the law on the securement of health rights & medical accessibility of the disabled should develop the standardized health enhancement programs for each disability type and severity. After examining the contents of health examination and health type of the disabled, the opinions about policies were suggested. Thus, in the future, there should be more detailed researches based on the tasks suggested by this study, and also the causal relations between health of the disabled and relevant programs should be continuously revealed.

Anti-inflammatory Effect of Oxya chinensis sinuosa Ethanol Extract in LPS-induced RAW 264.7 Cells (LPS로 유도된 RAW 264.7세포에 대한 벼메뚜기(Oxya chinensis sinuosa) 에탄올 추출물의 항염증 효과)

  • Yoon, Young-Il;Chung, Mi Yeon;Hwang, Jae-Sam;Goo, Tae-Won;Ahn, Mi-Young;Lee, Young-Bo;Han, Myung-Sea;Yun, Eun-Young
    • Journal of Life Science
    • /
    • v.24 no.4
    • /
    • pp.370-376
    • /
    • 2014
  • Although the grasshopper Oxya chinensis sinuosa has long been used as food in Korea, there is little data on its functional effects. In this study, we investigated the anti-inflammatory effect of O. c. sinuosa ethanol extract (OCE) in RAW 264.7 mouse macrophage cells treated with lipopolysaccharide (LPS) for induction of inflammation. First, we determined that there is no cytotoxicity at $2,000{\mu}g/ml$ or less of OCE in RAW 264.7 cells. To evaluate the anti-inflammatory effects of OCE, we investigated expression levels of pro-inflammatory cytokines such as tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-6, and pro-inflammatory enzymes such as inducible nitric oxide synthase (iNOS) and cyclo-oxygenase-2 (COX-2) in LPS-induced RAW 264.7 cells. In addition, we examined whether OCE could inhibit translocation of NF-${\kappa}B$ p65 into the nucleus in LPS induced RAW 264.7 cells. As a result, we found that the mRNA and protein levels of TNF-${\alpha}$ and IL-6 decreased in LPS-induced RAW 264.7 cells after treatment with OCE in a dose-dependent manner. In addition, we confirmed a $2,000{\mu}g/ml$ concentration of OCE inhibited translocation of NF-${\kappa}B$ p65 by immunnostaining and Western blot analysis, and a decrease in the protein expression levels of iNOS and COX-2. Accordingly, we suppose that OCE has an anti-inflammatory effect through down-regulation of TNF-${\alpha}$, IL-6, iNOS, and COX-2 related to ${\kappa}B$ p65 inflammatory signaling pathways.

Antioxidative Effects of Korean Bamboo Trees, Wang-dae, Som-dae, Maengjong-juk, Jolit-dae and O-juk (한국산 왕대, 솜대, 맹종죽, 조릿대 및 오죽의 항산화 효과)

  • Lee, Min-Ja;Moon, Gap-Soon
    • Korean Journal of Food Science and Technology
    • /
    • v.35 no.6
    • /
    • pp.1226-1232
    • /
    • 2003
  • Bamboo trees have been used for a long time as folk remedies for treatment of hypertension and stroke symptoms in Oriental regions. These pharmaceutical effects of bamboos look like to be related to its antioxidant capacity and phytochemicals in bamboos. To evaluate the antioxidative effects of bamboo trees, five kinds of bamboo varieties dominant in Korean peninsular were chosen and determined its total antioxidaive activities, free radical scavenging activities and nitrite scavenging activities by TEAC (Trolox Equivalent Antioxidant Capacity) assay, DPPH and Griess reagent assay using in vitro system, respectively. To evaluate the correlation between antioxidative activities and Maillard reaction during hot water extraction, contents of reducing sugar and total nitrogen and brown color intensity at 420 nm were determined. When total antioxidative activities, free radical scavenging activities and nitrite scavenging activities of five kinds of bamboo trees were compared, wang-dae (Phyllostachys bambusoides S. et Z.) showed the strongest effect among samples, although all kinds of extracts showed relatively strong effects against oxidation. The bamboo culms extract showed stronger antioxidative effects than that of bamboo leaves. In each fraction obtained from 70% ethanol extract, antioxidative effect were increased in order of dichloromethane>ethyl acetate>butanol>water>hexane fraction. In reducing sugar analysis of extracts, reducing sugar contents of water extracts were higher than that of 70% ethanol extracts and wang-dae water extract showed the highest level which was 708.92 mg/g. Total nitrogen contents of the extracts were $1.785{\sim}2.605\;mg%$ and contents in water extracts were lower than that in 70% ethanol extracts. Brown color intensity at 420 nm showed similar tendency with results in reducing sugar contents.