• Title/Summary/Keyword: Process tape

Search Result 318, Processing Time 0.03 seconds

Microstructure and Thermal Insulation Properties of Ultra-Thin Thermal Insulating Substrate Containing 2-D Porous Layer (2차원 기공층을 포함하는 초박형 단열기판의 미세구조 및 단열 특성)

  • Yoo, Chang Min;Lee, Chang Hyun;Shin, Hyo Soon;Yeo, Dong Hun;Kim, Sung Hoon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.30 no.11
    • /
    • pp.683-687
    • /
    • 2017
  • We investigated the structure of an ultra-thin insulating board with low thermal conductivity along z-axis, which was based on the idea of void layers created during the glass infiltration process for the zero-shrinkage low-temperature co-fired ceramic (LTCC) technology. An alumina and four glass powders were chosen and prepared as green sheets by the tape casting method. After comparison of the four glass powders, bismuth glass was selected for the experiment. Since there is no notable reactivity between alumina and bismuth glass, alumina was selected as the supporting additive in glass layers. With 2.5 vol% of alumina powder, glass green sheets were prepared and stacked alternately with alumina green sheet to form the 'alumina/glass (including alumina additive)/alumina' structure. The stacked green sheets were sintered into an insulating substrate. Scanning electron microscopy revealed that the additive alumina formed supporting bridges in void layers. The depth and number of the stacking layers were varied to examine the insulating property. The lowest thermal conductivity obtained was 0.23 W/mK with a $500-{\mu}m-thick$ substrate.

Development of energy-harvesting based safety apparel for night workers (야간 작업자를 위한 에너지 하베스팅 기반 안전의복 개발)

  • Yoon, Jung-A;Oh, Yujin;Oh, Hwawon;Lee, Younhee
    • The Research Journal of the Costume Culture
    • /
    • v.26 no.4
    • /
    • pp.503-518
    • /
    • 2018
  • The purpose of this study is to illustrate the design of safety suits based on energy-harvesting technology, particularly targeting street cleaners who must work at night with high mobility. The design focuses on applying lightweight energy-harvesting tools and illuminant into the wear. The design development reflects feedback from testers collected via survey constituting a key methodology. The development process has two main stages. Each stage uses a process of design prototyping, internal examination, test sampling, test wearing, and wearers' feedback via survey that consists of questions on visibility, wearing convenience, and washability. The first stage results show the design of safety suits with energy-harvested LED illuminant inserted and the survey results collected from street cleaners dressed in 4 sample and 80 actual suits in total. Improved based on the first-stage survey results, the second stage designs the suits with detachable energy-harvested EL tape. From these 5 sample and 30 actual second-stage suits, the additional survey indicates that this second-stage design facilitates more visibility and convenience in washing and wearing than the first-stage design. Accordingly, one can expect that this new design can apply not only to safety suits for night workers but also to handicapped or outdoor sportswear applications in the future.

A Study of Women’s Menopausal Experiences (여성의 폐경경험에 관한 연구)

  • 김미영;최수정;양승애
    • Journal of Korean Academy of Nursing
    • /
    • v.29 no.6
    • /
    • pp.1263-1272
    • /
    • 1999
  • This study was alone to identify the meaning and the essence of the menopause experience by means of the Colaizzi’s phenomenological method. The participants were eight women, 48-60 years old, who were experiencing perimenopause or postmenopause. They were selected using a theoretical sampling technique. Data were collected through in-depth interviews from April 6 to May 20, 1999. The interviews took from 40 to 90 minutes. Interviews were tape- recorded and analyzed using the constant comparative method. Significant statements from data were extracted. From these formulated meanings, 18 themes, 8 clusters of themes and 3 catagories were constructed. Final descriptions were found to be valid through the interviewee validation process. Essential themes of the menopausal experience which emerged were “coming of change”, “inclined to deny the in mind”, and “adapted life”. Menopause, as coming of change was the turning point in the women’s life cycle acompaning changes, in body and mind and marital life changes. Especially, the unpredictable menopausal changes were an opportunity to hide the fact of menopause and not to talk with anybody. Such a phenomenon reflected on the psychological attributes of menopausal woman such as an inclination to deny in the mind. Their experiences of menopause as adapted life were generally regarded as signalling the end of fertility and were interpreted as a natural developmental process that indicates a life transition. In conclusion, participants depicted the menopause as a natural stage in the life cycle. In order to help women have a positive life change and self accomplishment, nurses need to understand the essential themes of the menopausal experience. Thus, the importance of an open approach in eliciting the phenomena of menopause cannot be overemphasized. In conclusion, the results of this study suggest that exercise program is one of the effective interventions to improve the self-efficacy and also to lower the fatigue in the sample of female college students.

  • PDF

Using Multimedia to Improve Listening Comprehension in the EFL Classroom

  • Park, Seung-Won
    • English Language & Literature Teaching
    • /
    • v.8 no.2
    • /
    • pp.105-115
    • /
    • 2003
  • The four skills of a language are basically required for a communication. They are very important for a learner to develop the balanced language acquisition. Today both listening and speaking skills are emphasized in the global era rather than reading and writing proficiencies. The reason is really why the learners' communicative competence is more needed than the accurate knowledge of a structure in the language. For this reason, the listening comprehension should be taught effectively using the following strategies. First, the sound difference of a language must be taught. Language is a complicated process to convey the comprehensive meaning combined with the internal and external factors of a language. In other words, the meaning for the sound of language should be transmitted by the unit of vocabulary and syntax. Second, a good listening comprehension requires the familiarity and much experience with a lot of English words to understand English sentences unconsciously. Third, as understanding the structure of language is effective for the listening comprehension, the better listening comprehension can be possible through the meaningful exercise. Fourth, the compound process of listening comprehension requires the comprehensive understanding of language, but not the separate understanding of language. Fifth, the appropriate application of the multimedia courseware helps improve the listening comprehension better than that of the existing audio, video, tape recorder and so on. Using multimedia courseware is useful as follows: A learner is able to take as much lesson as he/she wants. It does take little time to repeat about what he/she takes a lesson. It gives the lively picture with the native speakers' voices. It gives him/her(a learner) a feedback effect continuously through the interaction of computer. It controls his/her lesson in accordance with the level of a learner.

  • PDF

Fabrication of silver stabilizer layer by coating process using nano silver paste on coated conductor (나노실버페이스트를 사용하는 코팅공정에 의한 coated conductor의 은 안정화층 제조)

  • Lee, Jong-Beom;Kim, Byeong-Joo;Kim, Hye-Jin;Yoo, Yong-Su;Lee, Hee-Gyoun;Hong, Gye-Won
    • Progress in Superconductivity and Cryogenics
    • /
    • v.11 no.1
    • /
    • pp.1-4
    • /
    • 2009
  • Mechanical and electrical properties of silver stabilizer layer of coated conductor, which as prepared with nano silver paste as starting materials, have been investigated, Nano silver paste was coated on a YBCO film by dip coating process at a diping speed of 20m/min. Coated film was dried in air and heat treated at $400{\sim}700^{\circ}C$ in an oxygen atmosphere. Adhesion strength between YBCO and silver layer was measured by a tape est(ASTM D 3359). Hardness and electrical conductivity of the samples were measured by pencil hardness test (ASTM D 3363) and volume resistance test by LORESTA-GP (MITSHUBISHD, respectively. The sample heat-treated at $500^{\circ}C$ showed poor adhesion 1B, but samples heat treated at higher than $600^{\circ}C$ showed enhanced adhesion of 5B. The silver layer heat-treated at $700^{\circ}C$ showed the high hardness value larger than 9 H, low volume resistance, surface resistance value as well as superior current carrying capacity compared to sputtered silver. SEM observations showed that a dense silver layer was formed with a thickness of about $2{\mu}m$. Dip coated silver layer prepared by using nano silver paste showed superior electrical and mechanical characteristics.

Planarization of SUS310 Metal Substrate Used for Coated Conductor Substrate by Chemical Solution Coating Method (화학적인 용액 코팅방법에 의한 박막형 고온초전도체에 사용되는 SUS310 금속모재의 평탄화 연구)

  • Lee, J.B.;Lee, H.J.;Kim, B.J.;Kwon, B.K.;Kim, S.J.;Lee, J.S.;Lee, C.Y.;Moon, S.H.;Lee, H.G.;Hong, G.W.
    • Progress in Superconductivity
    • /
    • v.12 no.2
    • /
    • pp.118-123
    • /
    • 2011
  • The properties of $2^{nd}$ generation high temperature superconducting wire, coated conductor strongly depend on the quality of superconducting oxide layer and property of metal substrate is one of the most important factors affecting the quality of coated conductor. Good mechanical and chemical stability at high temperature are required to maintain the initial integrity during the various process steps required to deposit several layers consisting coated conductor. And substrate need to be nonmagnetic to reduce magnetization loss for ac application. Hastelloy and stainless steel are the most suitable alloys for metal substrate. One of the obstacles in using stainless steel as substrate for coated conductor is its difficulties in making smooth surface inevitable for depositing good IBAD layer. Conventional method involves several steps such as electro polishing, deposition of $Al_2O_3$ and $Y_2O_3$ before IBAD process. Chemical solution deposition method can simplify those steps into one step process having uniformity in large area. In this research, we tried to improve the surface roughness of stainless steel(SUS310). The precursor coating solution was synthesized by using yttrium complex. The viscosity of coating solution and heat treatment condition were optimized for smooth surface. A smooth amorphous $Y_2O_3$ thin film suitable for IBAD process was coated on SUS310 tape. The surface roughness was improved from 40nm to 1.8 nm by 4 coatings. The IBAD-MgO layer deposited on prepared substrate showed good in plane alignment(${\Delta}{\phi}$) of $6.2^{\circ}$.

Fabrication of BSCCO Tube by Centrifugal Melting Process (원심 용융 성형법을 이용한 BSCCO 튜브 제조)

  • Kim Ki-Ik;Choi Jung Suk;Oh Sung Young;Jun Byung-Hyuk;Kim H.-R.;Hyun Ok-Bae;Kim Hyoung-Seop;Kim Chan-Joong
    • Progress in Superconductivity
    • /
    • v.7 no.1
    • /
    • pp.97-101
    • /
    • 2005
  • Bi-22l2 tubes for fault current limiter (FCL) were fabricated by centrifugal melting process. $SrSO_4$ ($10\;wt.\;\%$) was added to Bi-2212 powder to lower the melting point of Bi-22l2 and to improve the mechanical properties. The BSCCO powder was completely melted at $1300\;^{\circ}C$ using the RF furnace and then poured into rotating steel mold. The steel mold, preheated at $450\;{\circ}C{\sim}550^{\circ}C$ for 2 hour was rotated at $1020{\sim}2520\;RPM$. The solidified BSCCO tube was cooled down to room temperature in the furnace for 48 hours and separated from the mold between Bi-2212 and the mold. $ZrO_2$ solution was used to separate it easily from the mold and Ag tape was attached in the mold inner wall of the mold to analysis electrical property. Bi-22l2 tube was often cracked when the cooling rate was high. BSCCO tubes with $70{\Phi}{\times}100\;mm,\;50{\Phi}{\times}100\;mm$ and $30{\Phi}{\times}150\;mm$ size were fabricated by centrifugal melting process. The $J_{c}s$ of tubes with $50{\Phi}{\times}100\;mm{\times}4.0\;t$ and $50{\Phi}{\times}100\;mm{\times}4.l\;t$ were 178 and $74.2\;A/cm^2$ at 77K, respectively. The processing condition for Bi-2212 tube fabrication was investigated using XRD and SEM analyses.

  • PDF

Community Health Practitioner's Commitment into Community : on the Aspect of Primary Health Care (보건진료원의 지역사회 몰입과정)

  • Yun, Soon-Nyoung;Kim, Young-Im;Choi, Jeong-Myung
    • Research in Community and Public Health Nursing
    • /
    • v.6 no.2
    • /
    • pp.173-182
    • /
    • 1995
  • Primary health care(PHC) has been established since A Health Law for rural residents has been legislated in 1980 following the WHO declaration, 'Health for All 2000'. in 1978. PHC services are presently assumed to be provided by 2038 Community Health Practitioners(CHP) to about 28% out of rural population in Korea. Most CHPs have confronted the adaptation process to the community being practiced although a CHP's role is to evoke community participation for the improvement of their health by themselves. So the purpose of this study is to describe and explain of the commitment of CHPs into the community. Data were collected by direct interview and tape-recording under subjects' permission till theoretical saturation were occured from 6 CHPs. The subjects were 41 years old and have served in the community for 9 years in average. Main questions and concepts were explored from data according to the procedure of the grounded theory methodology. The results are as follows. 1) The number of the main concepts were twenty four that identified Motive, Desire, Personal characteristics, Unfamiliarity, Denial, Feeling of isolation, Self-sacrifice, Kindness, Patience, Assimilation, Respect for the residents, Support by the family, Support by the residents, Achievement, Acceptance of realities, Use of resources, Inducement of cooperation from the residents, Changes of the difference from time orientation between CHP and residents, Attitude as a official, Technical support, Cost management, Satisfaction level, Acknowledgement by the residents and discrepancy. 2) The twenty four concepts were categorized to seven groups such as Motivation, Feeling of Heterogeneity, Self-discipline, Social support, Induced changes in the attitudes of residents, Familarity and Persistent discrepancy. 3) The categorized groups were analyzed on the base of the Causal Conditions, Central Phenomena, Contexts, Intervening Conditions, Action / Interaction Strategies, and Consequences. Central phenomenon in this study was identified to be the feeling of heterogeneity. Community health practitioners experienced unfamiliarity and denial from the community and felt themselves isolated in the first. In time, they won the trust of residents by their efforts including self-sacrifice, kindness, patience, and assimilation. Afterward, practitioners got self-confidence and familiarity with lesser feeling of heterogeneity. Nevertheless, practitioners could not commit themselves completely because of the persistent discrepancy between CHP and residents. 4) On the commitment process, the CHPs' feeling of heterogeneity were decresed and social support increesed and newly evolved induced change of residents through the continuous interaction between CHP and them The contribution of this study would be concluded as follows. 1) It is expected that effective strategies for more rapid committment into the community can be developed based on this study. 2) More easy committment would be possible for the newly appointed CHP through understanding of the committment process identified on this study.

  • PDF

Synthesis characterization of a high conductivity LSCF cathode materials and electrochemical studies for IT-SOFC (중.저온 고체산화물 연료전지용 고전도성 공기극 소재 합성 및 전기화학적 특성 평가)

  • Kim, Hyoshin;Lee, Jongho;Kim, Ho-Sung;Lee, Yunsung
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2010.06a
    • /
    • pp.139-139
    • /
    • 2010
  • LSM is widely used as a cathode material in SOFC, because of its high electrochemical activity, good stability and compatibility with YSZ electrolyte at high temperature. However, LSM in traditional cathode materials will not generate a satisfactory performance at intermediate temperature. In order to reduce the polarization resistance of cell with the operating temperature of SOFC system, the cathode material of LSCF is one of the most suitable electrode materials because of its high mixed ionic and electronic conductivity. In this report, cathode material, $La_{0.6}Sr_{0.4}Co_{0.2}Fe_{0.8}O_3$ powder for intermediate temperature SOFC was synthesized by Pechini method using the starting materials such as nitrate of La, Sr, Co and Fe including ethylene glycol, etc. As a result, the synthesized powder that calcined above $700^{\circ}C$ exhibits successfully perovskite structure, indicating phase-pure of LSCF. Moreover, the particle size, surface area, crystal structure and morphology of the synthesized oxide powders were characterized by SEM, XRD, and BET, etc. In order to evaluate the electrochemical performance for the synthesized powder, slury mixture using the synthesized cathode material was coated by screen-printing process on the anode-supported electrolyte which was prepared by a tape casting method and co-sintering. Finally, electrochemical studies of the SOFC unit cell, including measurements such as power density and impedance, were performed.

  • PDF

A study on Check Pattern of Nail Art (네일 아트에 나타난 체크 패턴에 관한 연구)

  • Jeong, Seung-Eun;Kim, Jeong-Mee
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.17 no.1
    • /
    • pp.53-68
    • /
    • 2015
  • The purpose of this study is to analyze check pattern of nail art from 2011 to 2013. The results of this study are as follows; 1) Check pattern of nail art is total 257 patterns, and there are 84 argyle, 29 tartan, 24 harlequin, 24 over, 23 window-pane, 15 stitcheds, 13 hound tooth, 10 block, 10 madras, 8 gingham, 8 gradation, 7 shepherd, and 2 tattersall check patterns. Through this result, in nail art, the relatively simple patterns such as a vertical pattern, a horizontal pattern, and cross or overlap diagonal line are used more than elaborate and complex check patterns of a fibrous tissue from a weaving process. 2) In check pattern of nail art, N-affiliated color and R-affiliated color are remarkably well-used, because of the effects of argyle, tartan, window-pane, harlequin, stitched, over, and hound tooth check patterns used the most during the past three years. Especially, most tartan, harlequin, over, and hound tooth check patterns use their own special colors such as R-affiliated colors and N-affiliated colors as it is, and argyle, window-pane, stitched, and over check patterns use well by arranging N-affiliated colors and R-affiliated colors. 3) The most used expressive technique is hand painting to express check pattern in nail art, because new products related to UV gel are well launched. These materials can draw fine line that is hard to express by existing polish easily and simply, and not only have set quickly hard, so procedure time is very short, so it is compatible to draw check pattern personally, but also it is well covered, so check pattern is more clearly expressed.

  • PDF