• Title/Summary/Keyword: tape behavior

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A Study on the Evaluation of Tensile Performance According to Pareral Jointing Methods of the Sheet Membrane Waterproofing System (방수시트의 평행접합방법에 따른 인장성능 평가연구)

  • Lee Jeoung-Yun;Oh Mi-Hyun;Kwak Kyu-Sung;Oh Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • v.y2004m10
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    • pp.39-44
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    • 2004
  • A heat and room temperature construction method of asphalt have been mainly applying to rooftop waterproofing in concrete structure, and the rest construction method are sheet, membrane and mortar waterproofing construction method. In particular, joint method in sheet waterproof method is as overlap joint which on being reinforced with fiber and tape, have been applying for job site to mechanical fix using protection disk and anchorage and metal ironwork on the end of sheet. These construction method cause cutting off joint of sheet as behavior of structure according to repairs of sheet itself and thermal conduct, outdoor air environment. In conclusion, we analyzed and examined the application of various sheets and piece ashes about superior 'I' joint which divide from one and the other sheet and progressed about joint construction method of fixing method for overlap.

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Degradation Behavior of Critical Current in Bi-2223 Superconducting Tape in Bending-Tension Mixed Mode (인장-굽힘모드에서 Bi-2223 초전도 테이프의 임계전류 열화거동)

  • Shin, Hyung-Seop;Kim, Byung-Soo;Choi, Ho-Yeon;Oh, Sang-Soo;Ha, Dong-Woo;Ha, Hong-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07a
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    • pp.573-576
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    • 2003
  • HTS superconducting tapes are now commercially available for practical applications such as magnets and cables. Since superconductors in such applications are subjected to high mechanical loads that can significantly degrade the superconducting properties, mechanical properties and the strain tolerance known as the strain effect on superconducting properties are needed to be estimated for developing superconducting devices. Influences of loading mode on the Ic degradation and the interaction on strain effect were discussed in this study.

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Microwave Sintering Behavior and Electrical Properties of BaTiO$_3$ Thick Films (BaTiO$_3$ 후막의 마이크로파 소성 및 전기적 특성)

  • Bai, Kang;Kim, Ho-Gi
    • Journal of the Korean Ceramic Society
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    • v.35 no.11
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    • pp.1197-1202
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    • 1998
  • To check the possibility for microwave sintering of MLCC(multi layer ceramic capacitor) the tape cast-ed BaTiO3 thick films in zirconia insulation box were sintered by the domestic microwave oven. Microwave sintered samples had higher density lower porosity than coventionally sintered ones. but they didn't show Z5U electrical properties due to short sintering time about 15 minutes.

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Effect of Silicon Nitride Whisker Content on the Flexural Strength of Silicon Nitride-Boron Nitride-Silicon Carbide Multi-Layer Composites

  • Park, Dong-Soo;Cho, Byung-Wook
    • Journal of the Korean Ceramic Society
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    • v.40 no.9
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    • pp.832-836
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    • 2003
  • Multi-layer ceramic composites were prepared by tape casting followed by hot pressing using silicon nitride layer with silicon nitride whiskers, silicon nitride layer with silicon carbide particles and boron nitride-alumina layer. The whiskers were aligned during the casting. As the whisker content of the silicon nitride layer was increased up to 10 wt%, the flexural strength of the multi-layer composite was increased. However, further increase of the whisker content in the layer resulted in a rapid decrease of the strength of the composite. The results suggest that the strength of multi-layer ceramic composite showing non-catastrophic failure behavior can be significantly improved by incorporating the aligned whiskers in the layers.

Preparation and properties of Bi-based lead-free ceramic multilayer actuators

  • Nguyen, Van-Quyet;Han, Hyoung-Su;Lee, Han-Bok;Yoon, Jong Il;Ahn, Kyoung Kwan;Lee, Jae-Shin
    • Journal of Ceramic Processing Research
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    • v.13 no.spc2
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    • pp.282-285
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    • 2012
  • Lead-free (Bi0.5Na0.41K0.09)TiO3 (BNKT) multilayer ceramic actuators were prepared using tape-casting and screen-printing techniques. Co-firing behavior of BNKT/AgPd laminates was examined as a function of sintering temperature. It was found that co-firing induced bending and electrical properties were very sensitive to sintering condition. By optimizing sintering conditions, lead-free electrostrictive multilayer actuators with normalized strain Smax/Emax of 266 pm/V have been successfully fabricated, which is promising for lead-free actuator applications.

Magnetic field dependence of critical current and index n in a Bi-2223/Ag superconductor tape (Bi-2223/Ag 초전도 선재에서 임계전류와 인덱스의 자계의존성)

  • Kim Jung Ho;Kim Kyu Tae;Lim Jun Hyung;Jang Seok Hern;Rho Yun Bong;Joo Jinho;Choi Seyong;Nah Wansoo;Hong Gye-Won
    • Progress in Superconductivity
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    • v.6 no.1
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    • pp.79-83
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    • 2004
  • We fabricated Bi-2223/Ag superconductor tape with 55 filaments and estimated the magnetic field dependence of critical current (I$_{c}$) and index n (n) up to 30 T at 4.2 K. The I$_{c}$ and n were characterized as a function of external magnetic field parallel to the tape surface on increasing and decreasing field, using a 35 T hybrid magnet. The $I_{c}$ was estimated to be 325 A, and n was 32, 22, and 26 in the electric field range of $0.1 ∼1\mu$V/cm, 1∼10 $\mu$V/cm, and 0.1∼10 $\mu$V/cm, respectively, under self-field at 4.2 K. It was observed that $I_{c}$ was dependent on magnitude of magnetic field and it decreased exponentially as the field increased; in a parallel and increasing field, It was 128 A at 30 T which is approximately 40% of critical current in self-field. In addition, the $I_{c}$ was higher on decreasing field than that on increasing one. On the other hand, n did not significantly depend on field strength up to 30 T, nor varied on whether increasing or decreasing field; n value in 0.1∼1 $\mu$V/cm was 23.0$\pm$5.2 and 27.8$\pm$8.0 on increasing and decreasing field, respectively. The n value on decreasing magnetic field was slightly higher than that on increasing field. This hysteretic behavior of n was similar to that of$ I_{c}$, which is related to the trapped flux at the grain boundary.ary.

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Effects of vision care program for elementary school children (시력증진 프로그램이 초등학생의 시력에 미치는 효과)

  • 이정렬;유일영;이은숙
    • Korean Journal of Health Education and Promotion
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    • v.16 no.1
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    • pp.137-148
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    • 1999
  • The necessity of school health promoting projects is well known to many researchers, however, there is a lack of research on the development of strategies for school health programs and the evaluation of the effectiveness of the programs. The results of our previous study in 1996 identified poor eyesight as one of the several health problems among elementary school children in urban areas. The main objective of this study is to develop, implement, and evaluate vision care for elementary school children. The research method utilized a quasi experimental design using non-equivalent group, pre-post comparison. The sample consisted of all second grade children in two elementary schools in Kyung-giProvince. In order to prevent a contamination effect of the vision care program, one school was selected as a control and the other school was selected as a treatment group. The experimental school had 467 children and the control school had 402 children. The visual acuity of children in both group was measured and a survey questionnaire was sent out to parents on the knowledge, attitude, and behavior related to vision care before the program was implemented. The children of the experimental school received the following programs; separate education on proper nutrition and care of eyesight for children and parents, daily eye exercises using video tape, and an essay and poster contest on healthy eyesight. The eye exercise program lasted from March, 1997 to November, 1997. On November, 1997, visual acuity was measured again from children in both schools. The data was analyzed by using SAS statistical package. The results indicate that the children in the experimental group had significantly (p〈0.001) better eyesight than the children in the control group. Also, some of the behavior highly related to the poor eyesight are poor maternal eyesight and watching TV from a short distance. In conclusion, one of the significance of this project is that the vision care program was developed after the need assessment. It will be encouraged in the future that more school health program should be developed after a need assessment. Also, inclusion of family members was important in health promoting projects within a school setting since healthy behavior needs to be reinforced at horne as well as at school.

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Control of Explosion Behavior in Micro Hole Using UV Laser on LTCC Green Sheets Containing Carbon Particles (카본을 첨가한 LTCC 그린 시트에서 UV 레이저를 이용한 미세 홀 터짐 현상 제어)

  • Kim, Shi Yeon;Ahn, Ik-Joon;Yeo, Dong-Hun;Shin, Hyo-Soon;Yoon, Ho Gyu
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.29 no.12
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    • pp.786-790
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    • 2016
  • Hole explosion behaviors were observed during drilling fine holes with laser beam on the LTCC green bar of $320{\mu}m$ thick after lamination of green sheets prepared by tape casting of thick film process. The incidence of these hole explosions was inversely proportional to hole sizes. The incidence of hole explosion was 20 % number of hole with the size of $60{\mu}m$ exploded for the UV radiation, while the explosion did not appear for hole sizes over $100{\mu}m$. To prevent hole explosion behavior during laser-drilling of fine holes, carbon black powder was added as an additive in the LTCC composition, which has superior thermal durability. As a consequence, hole explosion rate was suppressed to 0.8 % for the hole size of $50{\mu}m$ green sheet with the carbon black amount of 10 weight % and the laser power of 3 watt. Added carbon is thought to reduce the heat-affected region during laser drilling.

The Observationi of User Behaviors of the Urban Plaza using Time-Lapse Record-A case study of Chungryangri Station Plaza- (Time-Lapse 촬영방법을 이용한 도심 광장의 이용행태에 관한 연구 -청량리 역광장을 사례로-)

  • 조창완;진양교
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.3
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    • pp.199-212
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    • 1998
  • The ultimate goal of this study can be summed up as follows: First, the utility of Time-Lapse that observes and records people's behavior will be shown and its merits and demerits will be discussed through comparing with other data-collecting methods such as the naked- eye observation, and the specific way in which Time-Lapse can be put to use will be suggested. Second, analysis of use behavior boserved in the plaza of Chungryangri station by Time-Lapse will be made, on the basis of which suggestions will be made concerning planing, designing, layout, and management of the station plaza. Time-Lapse can observe and records the plaza of Chungryangri Staton through 6 different ways of recording in Time-Lapse: 30 seconds, every minute, every two minutes, second every five minutes, every one tenth of a second, and every one fifth of a second, and these different ways of recording were analyzed through comparison from one to each other to check their respective utilities. And also analysis of tracks of pedestrians, density, and use behavior of users were made, according to which the way in which Time-Lapse can be utilized was examined. Several useful results obtained from this study are shown as follows. First, Time-Lapse made it possible to continuously observe for a long time using minimu efforts, and a single tape which is able to cover from 12 hours up to 25 days is useful for observing variation of behavior in space with the passage of time and seasons. Second, among six ways of recording, the recording every one tenth of a second and every one fifth of a second are useful for finding the tracks of pedestrians, the number of users, the member compositions, the time spent in one place, and manner of use. And besides the moving direction and its purpose can be recognized in a short time, which makes it possile to see where crossings of moving directions occur. Third, the recording every thirty seconds, every minute, every two minutes, and every five minutes are useful for analyzing the density in space as well as for finding the number of users and frequency of facilities use. In particular the recording every thirty seconds made it possible to keep the track of pedestrians' walking, and to observe even slowly moving motions such as cleaning. But when the recording interval exceeds one minute, this was not possible. Fourth, time-lapse has advantages over the naked eye observation in several respects. Time-lapse can measure observed behavior and density in terms of number, and locate the position of users. Time-Lapse, if accompanied by other methods such as interviewing and question that can examine psychological aspects like satisfaction or the purpose of use and be a useful device for space studies.

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Nurses's Experience of Verbal Violence in Hospital Setting (병원 내 간호사의 언어폭력 경험에 관한 연구)

  • Lee, Soon-Hee;Chung, Seung-Eun
    • Journal of Korean Academy of Nursing Administration
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    • v.13 no.4
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    • pp.526-536
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    • 2007
  • Purpose: The purpose of this phenomenological research was to identify nurses's experience of verbal violence from doctor in hospital setting. Methods: The participants of this study were twelve nurses who work at a hospital in Chungbuk. Data was collected through documents, observation, and tape-recorded in-depth interview individually from participants. It was analyzed using the phenomenological methodology by Colaizzi. Results: From significant statements, seven categories were identified as follows: Lowering self-esteem due to authoritative and insulting remarks, Getting angry and being disagreeable due to blunt remarks, Being disgraceful due to broad jokes sexually, Hoping to escape present due to skepticism in their job, Being estranged due to bad feeling, Expressing their anger, and Using various way for improvement of relationship. Conclusion: Nurses's experience of verbal violence was showed nurse-doctor relationship was still vertical, not collaborative and supportive. This vertical relationship would cause conflicts between doctor and nurse. Therefore it is need doctor to be changed the mind that nurse is a professional, and to come up with the plan for enhancing inter-collaborative relationship in order to solve conflict between them.

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