• 제목/요약/키워드: Wear-Growth

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Study about the Increase of Welfare, Medical Care and Education Effect in the River

  • Ito, Kazumasa;Fukunari, Kozo;Tsukamoto, Noboru;Yoshikawa, Katsuhide
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2010년도 학술발표회
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    • pp.132-139
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    • 2010
  • The river technology of Japan was highly developed and achieved much result in flood protection, water use and the environment. Nowadays, the function which is requested to the river is changes because the society changes from growth to maturity. In this study, we suggest the functions of the river in the maturity society about future welfare, medical care and education based on field research of case study. In this research, we pay attention to the functions related with culture, one) function of healing, mental stress improvement and life, two) function of landscape, education and recreation. And this paper proposed the usage of the river where adopt to the times, a function and the value of "the river as the space". We made a questionnaire to 187 river managers, and 90% of answers wear positive for use the river as the medical aspect, health and the welfare. Furthermore, based on research result of hospitals and welfare facilities which used a river for their activities, we suggest to develop and use the river walk, to design a city and rivers as one, and to use many facilities which are located on river front more active, those are improve the new river functions.

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자동차엔진용 금속기 복합재료의 피로균열거동에 관한 연구 (A Study on Fatigue Crack Behavior of Metal Matrix Composites for Automobile Engine)

  • 박원조;허선철;정재욱;이해우;부명환
    • 한국자동차공학회논문집
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    • 제11권5호
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    • pp.140-146
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    • 2003
  • Metal matrix composites had generated a lot of interest in recent time because of their high specific strength and stiffness in specific properties. It was also highlighted as the material of frontier industry because strength, heat-resistance, corrosion-resistance and wear-resistance were superiored. In this study, the strength properties of $Al_{18}B_{4}O_{33}$/AC4CH composites were represented mixing the binder of $SiO_2$. It was also fabricated by squeeze casting. $Al_{18}B_{4}O_{33}$/AC4CH was fabricated at the melt temperature of $760^{\circ}C$, the perform temperature of $700^{\circ}C$ and mold temperature of $200^{\circ}C$ under the pressure of 83.4MPa. Consequently, fatigue life was observed roughly in the order of AC4CH> nobiner> $SiO_2$, independently on crack propagation direction and stress ratio.

니트웨어 상품 기획의 실제적 연구 (A Study on Product Planning of Knitwear Commodity)

  • 이인숙;조규화
    • 패션비즈니스
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    • 제12권1호
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    • pp.1-15
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    • 2008
  • This study aims to consolidate the qualitative growth of knit design thru the creation of high value-added brand and design, in the state of active trend for competitive promotion of professional knit brand, by collapsing the border line between the knitwear market and the woven one. In accordance with the market situation of increasing a demand of knitwear products, I wish to awaken the importance of knit design thru this study, to survey domestic knit brand products and their planning directions and to plan for the high value-added knitwear products, thru presenting the problems of knit industry and developing knitwear design. This study is focused on showing process of planning and items developed personally by me in charge of developing products practically at the job site of knit industry. From the stage of planning for goods, I suggested the 2007 s/s goods of M company as a strategy of distinctiveness caused by the problems with rival companies, and also proposed a method conducted by the actual business. Setting up M company's s/s concept of the year 2007, I suggested a plan of quantity, time of forwarding, color, fabrics, etc. as well as the process and schedule thru order, and based on the above result, I made a planning for 2007 s/s knitwear for middle-aged women.

Effect of Free Abrasives on Material Removal in Lap Grinding of Sapphire Substrate

  • Seo, Junyoung;Kim, Taekyoung;Lee, Hyunseop
    • Tribology and Lubricants
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    • 제34권6호
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    • pp.209-216
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    • 2018
  • Sapphire is a substrate material that is widely used in optical and electronic devices. However, the processing of sapphire into a substrate takes a long time owing to its high hardness and chemical inertness. In order to process the sapphire ingot into a substrate, ingot growth, multiwire sawing, lapping, and polishing are required. The lap grinding process using pellets is known as one of the ways to improve the efficiency of sapphire substrate processing. The lap grinding process ensures high processing efficiency while utilizing two-body abrasion, unlike the lapping process which utilizes three-body abrasion by particles. However, the lap grinding process has a high material removal rate (MRR), while its weakness is in obtaining the required surface roughness for the final polishing process. In this study, we examine the effects of free abrasives in lap grinding on the material removal characteristics of sapphire substrate. Before conducting the lap grinding experiments, it was confirmed that the addition of free abrasives changed the friction force through the pin-on-disk wear test. The MRR and roughness reduction rate are experimentally studied to verify the effects of free abrasive concentration on deionized water. The addition of free abrasives (colloidal silica) in the lap grinding process can improve surface roughness by three-body abrasion along with two-body abrasion by diamond grits.

미얀마의 분쟁해결제도와 비즈니스협상 (Dispute Resolution Institution and Business Negotiation of Myanmar)

  • 정용균
    • 한국중재학회지:중재연구
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    • 제28권4호
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    • pp.61-88
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    • 2018
  • Myanmar has witnessed rapid economic growth in the 21st century. The cultural heritage of Myanmar (Burma) inherited from ancestors is law literature such as Dhammathat and Rajathat. Burma is a unique country in Southeast Asia in a sense that it already had a modern law system. For example, there has been a legal profession even in 12th century AD. According to Rajathat, lawyers were required to wear a uniform in court. Furthermore, lawyers and Judges participated in legal proceedings from the 15th century. As to the role of Dhammathat, there are conflicting views in the academic community. According to Professor Andrew Huxley, the profound literatures of Dhammathat had played an important role as a source of law in Burmese court in ancient times. Dhammathats have flourished in the struggle among the King, lawyers, and monks in old Burmese society. This customary law combined with Rajathat provided a guidance of legal proceedings in Burmese court, as well as village settlement. This traditional dispute resolution system reaches modern times in the form of Buddhist family law in Myanmar. Nowadays, the law system of Myanmar looks like a legal pluralism since the customary laws of Burma, as well as Shan and Arakan, are effective and co-exist with common law adopted at the colonial period. In recent times, Myanmar has enacted new arbitration laws (2016) in order to attract foreign direct investment.

Growth of SiC Oxidation Protective Coating Layers on graphite substrates Using Single Source Precursors

  • Kim, Myung-Chan;Heo, Cheol-Ho;Park, Jin-Hyo;Park, Seung-Jun;Han, Jeon-Geon
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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    • pp.122-122
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    • 1999
  • Graphite with its advantages of high thermal conductivity, low thermal expansion coefficient, and low elasticity, has been widely used as a structural material for high temperature. However, graphite can easily react with oxygen at even low temperature as 40$0^{\circ}C$, resulting in CO2 formation. In order to apply the graphite to high temperature structural material, therefore, it is necessary to improve its oxidation resistive property. Silicon Carbide (SiC) is a semiconductor material for high-temperature, radiation-resistant, and high power/high frequency electronic devices due to its excellent properties. Conventional chemical vapor deposited SiC films has also been widely used as a coating materials for structural applications because of its outstanding properties such as high thermal conductivity, high microhardness, good chemical resistant for oxidation. Therefore, SiC with similar thermal expansion coefficient as graphite is recently considered to be a g행 candidate material for protective coating operating at high temperature, corrosive, and high-wear environments. Due to large lattice mismatch (~50%), however, it was very difficult to grow thick SiC layer on graphite surface. In theis study, we have deposited thick SiC thin films on graphite substrates at temperature range of 700-85$0^{\circ}C$ using single molecular precursors by both thermal MOCVD and PEMOCVD methods for oxidation protection wear and tribological coating . Two organosilicon compounds such as diethylmethylsilane (EDMS), (Et)2SiH(CH3), and hexamethyldisilane (HMDS),(CH3)Si-Si(CH3)3, were utilized as single source precursors, and hydrogen and Ar were used as a bubbler and carrier gas. Polycrystalline cubic SiC protective layers in [110] direction were successfully grown on graphite substrates at temperature as low as 80$0^{\circ}C$ from HMDS by PEMOCVD. In the case of thermal MOCVD, on the other hand, only amorphous SiC layers were obtained with either HMDS or DMS at 85$0^{\circ}C$. We compared the difference of crystal quality and physical properties of the PEMOCVD was highly effective process in improving the characteristics of the a SiC protective layers grown by thermal MOCVD and PEMOCVD method and confirmed that PEMOCVD was highly effective process in improving the characteristics of the SiC layer properties compared to those grown by thermal MOCVD. The as-grown samples were characterized in situ with OES and RGA and ex situ with XRD, XPS, and SEM. The mechanical and oxidation-resistant properties have been checked. The optimum SiC film was obtained at 85$0^{\circ}C$ and RF power of 200W. The maximum deposition rate and microhardness are 2$mu extrm{m}$/h and 4,336kg/mm2 Hv, respectively. The hardness was strongly influenced with the stoichiometry of SiC protective layers.

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Oral Screen의 임상 적용에 대한 고찰 (APPLICATION OF AN ORAL SCREEN)

  • 박소영;정태성;김신
    • 대한소아치과학회지
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    • 제27권2호
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    • pp.246-250
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    • 2000
  • Oral screen은 가장 기본적인 기능성 장치로서, 근육의 변화를 도모하여 비정상적인 근육형태와 연관된 초기부정교합의 개선에 적합하다. 이것은 혀와 buccinator mechanism사이의 근평형을 향상시켜, 정상적인 성장이 가능하도록 한다. Oral screen은, (1) 손가락빨기 혀내밀기, 입술깨물기 등의 구강습관, (2) 기도가 열려있을 때의 구호흡, (3) 상악전돌경향을 동반한 경미한 원심교합, (4) 유치열과 혼합치열에서의 개방교합, (5) 무력순 등을 개선하는데 사용된다. Oral screen은 매일 밤, 그리고 가능하다면 낮에도 장착하여야 한다. 장치의 효과는 구순폐쇄훈련을 시행함으로써 발휘된다. 장치를 장착하는 동안, 입술은 장치의 효과를 높이고 구순폐쇄를 향상시키기 위해 항상 접촉한 상태로 유지되어야 한다. 본 증례는 구호흡과 무력순을 보이며 각각 상악절치의 순측경사와 치은비대, 개방교합 양상을 보이는 2명의 어린이환자에게 구순폐쇄훈련을 병행하면서 oral screen을 장착한 결과, 구호흡경향이 줄어들어 치은부종이 감소하였고 구순의 근력과 길이는 증가하여 구순폐쇄가 원활해졌다. 아울러 상악 절치의 경사도가 감소되어 개방교합의 치료에 효과적임을 알 수 있었다.

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치과용 자석부착장치의 물리적, 생물학적 특성에 관한 연구 (A STUDY ON THE PHYSICAL PROPERTIES AND BIOLOGICAL CHARACTERISTICS OF DENTAL MAGNETIC ATTACHMENTS)

  • 임용식;김영수;김창회;김용호
    • 대한치과보철학회지
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    • 제37권1호
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    • pp.1-22
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    • 1999
  • In order to investigate various physical and biological properties of dental magnetic attachments studies on retentive characteristics, corrosion properties, cytotoxicity of different magnetic systems for dental applications were done. For the study of retentive characteristics changes of retentive force by increasing air gap, wear properties of various attachment systems and loss of magnetic force by heat treatment were measured. Forte study of corrosion property of magnet covering metal electrochemical corrosion was done in artificial saliva and 0.9% NaCl solution between $-1,000mV_{SCE}\;and\;+1,000mV_{SCE}$. Anodic polarization curves are obtained about 6 types of samples and 2 types of solution. Corroded surfaces were examined with metallurgical microscope, scanning electron microscope and surface profilometer. For the study of cytotoxicity of magnetic attachment and its field cell growth and agar overlay test were done. The results of this study were as follows. 1. In Magnetic attachments using closed circuit retentive force at zero air gap was greater than magnets using open circuit, but decrease of retentive force by increasing air gap was also greater than open systems. 2. After 40,000 cycles of wear test all mechanical attachment resulted in varing degree of retention loss but in magnetic attachments no loss of retentive force was observed. 3. The magnetic attachment using Neodymium magnet showed early loss of retentive force about $200^{\circ}C$ but attachment using Samarium magnet showed some resistance to heat treatment and complete retention loss was observed about $500^{\circ}C$. The keeper was not influenced by heat treatment in retention. 4. In electrochemical corrosion test Dyna magnetic attachment covering metal showed the highiest corrosion resistance and Shiner magnet covering metal showed the least corrosion resistance and examination of corroded surface with metallurgical microscope, scanning electron micro-scope and surface profilometer also showed same results with anodic polarization corves. 5. The result of cell culture tests on the magnet covered with metal showed least recognizable cytotoxicity.

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규산 함유 액상비료 시비에 따른 크리핑 벤트그래스의 생육과 품질 변화 (Growth and Quality Changes of Creeping Bentgrass by Application of Liquid Fertilizer Containing Silicate)

  • 김영선;이창은;이긍주
    • Weed & Turfgrass Science
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    • 제5권3호
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    • pp.170-176
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    • 2016
  • 본 연구는 규산 함유 액비(LFSi)의 시비에 따른 잔디의 생육과 품질의 변화를 확인하기 위해 잔디의 가시적 품질, 줄기 밀도, 뿌리 길이, 엽록소 함량, 예지물 및 양분 함량을 조사하였다. 처리구는 대조구(CF), LFSi 1,000배 처리구(SiF-1), LFSi 500배 처리구(SiF-2) 및 LFSi 250배 처리구(SiF-3)로 구분되었다. LFSi 처리 전후에 토양화학성은 차이를 나타내지 않았다. LFSi 처리구와 대조구를 비교하였을 때, 잔디 품질은 7월, 10월 및 11월 조사에서 높았으며, 엽록소 함량과 잔디 예지물은 10월 27일 조사에서 증가하였다. 줄기 밀도, 뿌리 길이, 잎조직 내 질소 함량 및 칼륨 함량은 LFSi 처리구에서 증가하였다. 잔디 잎 조직 중 규소 함량은 칼리 함량이나 줄기 밀도와 정의 상관성을 보였고, 줄기 밀도는 잔디 품질이나 엽록소 함량과 각각 정의 상관성을 나타내었다. 이 결과들을 종합해 볼 때, 크리핑 벤트그래스에서 규산 함유 액비의 시비는 잔디의 잎 조직 중 칼륨 함량이나 줄기 밀도가 증가되어 가시적 품질이 향상되는 것을 확인 할 수 있었다.

유·아동복 브랜드 구성요소의 특성 (Characteristics of Components in Infant and Children's Clothing Brand)

  • 나수임
    • 한국의상디자인학회지
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    • 제13권1호
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    • pp.135-146
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    • 2011
  • Despite the recession that has affected people's consumption of clothing, the 'Gold Kids' market shows steady growth. This study analyzed the characteristics of components that make up infant and children's wear brands. Firstly, this study found the linguistic features of infant and children's clothing brands. Most brand names have common characteristics such as idiomatic expressions, combination and separation of vocabulary, and more than 6 syllables. Also, when they formative brand quality, they frequently used words like 'girl', 'kid' and 'baby' to clarify the category of the brand product. Also it is meant to present a clear brand concept to the target consumer to offer their brand information and product characteristics. Moreover, English is widely used in the brand names, and they used appropriate symbol graphics that fit the titles and qualities of the brands. Second, to strengthen their brand identity and inherent concepts, infant and children's clothing brands normally use their own particular brand colors wich makes special and strong visual impressions on the target consumer. Also, they mainly use applied sans serif typeface showing the softer brand quality. Brand logos have different visual expressions depending on their brand value and the target consumer. The word type of the logos presents clear brand identity and information to the target consumer. Through the study, we found that infant and children's clothing brands tend to use written brand names for the logo type more than graphic symbol logo patterns. This indicates that infant and children's clothing brands tend to emphasize information transfer rather than visual graphic symbols when they organize brand logos.

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