• 제목/요약/키워드: Surface appearance

검색결과 787건 처리시간 0.027초

Effect of bath conditions and pulse parameters on tin surface finish for microelectronic packaging applications

  • Sharma, Ashutosh;Jung, Do-hyun;Jung, Jae-pil
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2015년도 추계학술대회 논문집
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    • pp.232-233
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    • 2015
  • The effects of various bath conditions such as surfactant concentration, bath pH, bath temperature, agitation of bath; as well as pulse parameters such as cathodic current density, pulse duty cycle and frequency, on the grain size, surface finish, and appearance of the tin plated coatings have been investigated. The plating bath under investigation is an aqueous acidic solution composed of a mixture of $SnSO_4$, $H_2SO_4$, and a surfactant. The bath conductivity and pH are measured by a glass pH electrode. The microstructure of the coatings produced is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and surface profilometry. XRD analysis shows that the deposits consist of tetragonal ${\beta}$-Sn crystal structure irrespective of plating conditions. The mechanism involved in the morphology evolution in response to various parameters and conditions has also been discussed.

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Zn-Ni 합금전기도금강판의 표면특성에 미치는 첨가제 영향 (Effect of additives on surface properties of Zn-Ni alloy Coating)

  • 김현태;장삼규;정원섭
    • 한국표면공학회지
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    • 제31권4호
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    • pp.191-198
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    • 1998
  • The effect of the additives on the Zn-Ni alloy electrocrystallization from a chloride bath was investigated by means of electrochemical methodes, scanning electron microscopy and measurement of surface appearancd, X-ray diffraction patterns. The additives thestd ware the Saccharin, surfactant of naptalene-derivative and mixed additive, The resistance of electrodeposit increased by adding the additives, whera the effect of additives on resistance was different with current density roughness, apperarance and morphology of deposit were also influenced by the type of additive. The deposir with fine, compact grains as well as good surface roughness and appearance was obtained from the mixed-additive added bath.

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남성용 작업복 팬츠 3차원 가상착의 시뮬레이션 평가 (The Computerized 3-D Clothing Simulation for the Evaluation of Men's Working Pants)

  • 박진아
    • 복식
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    • 제63권8호
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    • pp.27-42
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    • 2013
  • The study was aimed to develop men's working pants patterns through the computerized 3-D virtual clothing simulation system and to verify the effects of the 3-D simulated outfit by comparing it to the images of the actual outfits. The average body measurements of South Korean men aged between 30 and 39 used for the simulation in order to generate a 3-D virtual model and to realize outfits of men's working pants for the workers in the heavy industry in South Korea. And also the preliminary questionnaire survey results on certain aspects of the working pants such as type, detailed design preference and discomforting parts were taken into consideration. Both the simulated and real images of the developed working pants were compared in terms of the ease amount according to parts of the working pants, the position of seam lines, the appearance of darts and pleats, and the effects of the fabric surface according to expertise panels' subjective 5-point scale evaluation. The results throughout the study were (1) the basic working pants item worn by subject workers were the straight one pleated pants. The most discomforting parts of the working pants were in the order of body rise, thigh, hip, waist, pants hems and knee girth. (2) the drafting factors of pants patterns differed by the men's body features, which was related to the allocation of suppression amounts between waist and hip girths into darts and hip curve amounts on the waist line level of the pants. (3) the similarity of the virtually simulated and real images of men's working pants resulted in an average of 4.5 to the ease of appearance, 4.6 to the seam lines, 4.1 to the fabric surface effects in a 5-point scale, which means that the two were highly alike.

유과 제조 시 반죽과 반대기의 품질 특성에 미치는 꽈리치기 공정과 건조 공정의 영향 (Effects of Punching and Drying Process on Quality Characteristics of Yukwa Dough and Yukwa Bandegi during Preparation of Yukwa)

  • 이미혜;오명숙
    • 동아시아식생활학회지
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    • 제25권6호
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    • pp.1029-1040
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    • 2015
  • Effects of punching and drying process on quality of Yukwa were determined. Lightness (L) of Yukwa dough with punching was higher than that with no punching. Air cell distribution of Yukwa dough was fine with higher punching. Microstructure of Yukwa dough showed a broken surface structure with increasing punching. Hardness and adhesiveness of Yukwa dough decreased after 5 min of punching and then increased with higher punching. Expansion ratio of Yukwa base with punching at 155 rpm for 5 min was highest among the samples. Appearance of Yukwa base with no punching showed a poor shape and cross section, whereas Yukwa base with punching at 95 rpm for 10 min showed the best appearance and cross section and Yukwa base with punching at 155 rpm for 5 min also showed good appearance. The moisture content of Yukwa Bandegi after 24 hr of drying was 14.93%. Microstructure of Yukwa Bandegi showed a broken surface structure and empty spaces with increased drying time. Expansion ratio of Yukwa base with 24 hr of drying at $40^{\circ}C$ was highest among the samples. Overall, optimum punching conditions were 10 min of punching at 95 rpm or 5 min of punching at 155 rpm and optimum drying condition was 24 hr of drying at $40^{\circ}C$.

국소적 치아 이형성증(Regional odontodysplasia)에 대한 증례 (REGIONAL ODONTODYSPLASIA : CASE REPORT)

  • 이제호;조재현;김기덕;최병재
    • 대한소아치과학회지
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    • 제28권1호
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    • pp.175-179
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    • 2001
  • 국소적 치아 이형성증이란 드물게 나타나는 치아발육장애로서 치아발육이 국소적으로 정지되어 발생되며 이환된 치아의 모든 구성요소가 발육부전이나 석회화 부전을 나타낸다. 국소적 혈액 순환 장애, 체성 돌연변이. 바이러스 침투, 치배 감염, 치아 외상, 이상고열, 방사선조사, 영양, 대사 장애, 유전 등이 원인으로 제시되고 있으나 정확한 원인은 밝혀져 있지 않다. 여성에 많이 발생하고(1.4 : 1) 하악보다는 상악(특히 좌측)에 많이 나타나는 것으로 보고되고 있다. 이환 받은 치아는 크기가 작고, 저형성을 보이며, 노란색 또는 노란 갈색을 띄고, 소와와 구(pitting & grooving)를 보이기도 한다. 방사선적으로 "ghost like appearance" "fuzzy appearance"등을 보이고 치수강 내에 치수석회화물이나 상아질석이 보이기도 한다. 본 증례의 2세 남자 환아는 하악 우측 치아의 맹출 지연을 주소로 연세대학교 병원 소아치과에 내원하였다. 하악 우측 유중 절치의 부분 맹출과 유측절치, 유견치, 제 1유구치가 미맹출을 보였고, 방사선 검사소견에서 해당부위의 치아는 "Ghost like appearance"와 짧은 치근, 개방된 치근첨의 소견이 관찰되었다. 임상, 방사선 검사결과 국소적 치아 이형성증으로 판단되어 이에 대한 보고를 하는 바이다.

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평면재단과 입체재단 비교를 통한 체형별 원형 연구 (A Study on the Drafting Method According to the Somatotype)

  • 이정임
    • 한국의류학회지
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    • 제15권3호
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    • pp.309-320
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    • 1991
  • The purpose of this study was to develope a pattern drafting method for various somatotype which contribute largely to increase the fitness and comfort of garments. This study had 8 subjects who were college girls who had prominent somatic characteristics. The study was carried out by the following procedures. 1. The 8 subjects who had prominent somatic characteristics were cheesed by photograph- ing. The somatotypes of 8 subjects were classified into Standard somatotype, Turning over somatotype, Bending somatotype and Turning over-Bending somatotype. 2. Under the criterion of the body surface development, the comparative investigation on the pattern and the sensory evaluation were accomplished in the flat pattern method and the draping pattern method. 3. The body surface development of them were made by the draping pattern method. 4. In the result of the comparative investigation and the sensory evaluation, it was found that the flat pattern had better appearance and comfort than the draping pattern, and the draping pattern included more somatic characteristics than the flat pattern. 5. On the basis of those result, the pattern drafting method according to the somatotype was indicated and it was examinated by the clothing experiment. 6. The sensory evaluation for appearance and comfort was applied to evaluate the new basic pattern for four somatotype by comparing it with the conventional basic pattern (Rim, won ja' 5). The result of the sensory evaluation, it was found that the new basic pattern was more suitable for each somatotype than the conventional basic pattern.

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Spatio-Temporal Variation of Cold Water Masses along the Eastern Coast of Korea in 2013 and 2014

  • Han, In-Seong;Park, Myung-Hee;Min, Seung-Hwan;Kim, Ju-Yeon
    • 해양환경안전학회지
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    • 제22권3호
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    • pp.286-295
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    • 2016
  • With the results of observations in 2013 and 2014 including ocean buoys, in-situ investigations and wind data, we examined the spatio-temporal variation of cold water masses along the eastern coast of Korea. Usually, a cold water mass first appears along the northern part of the eastern coast from May to July, and then along the southern part of the eastern coast from late June to mid-August. Cold water masses appear 3~5 times a year and remain for 5~20 days in the southwestern part of the East Sea. A distinctive cold water mass appeared usually in mid-July in this area, the surface temperature of which was below $10^{\circ}C$ in some cases. During the appearance of a cold water mass in the southwestern part of the East Sea, the horizontal temperature gradient was large at the surface and a significant low water temperature below $8^{\circ}C$ appeared at the bottom level. This appearance of cold water masses clearly corresponded to southwesterly winds, which generated coastal upwelling.

폴리아닐린과 첨가제에 따른 아연전기도금층의 표면 외관 특성 (Characteristics of Surface Appearance of Zn Electrodeposits with Polyaniline and Additives)

  • 이상백;박형호;배인성;윤재식;김병일
    • 한국재료학회지
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    • 제12권2호
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    • pp.146-152
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    • 2002
  • Effect of polyaniline and additives on surface appearance of Zn electrodeposition was investigated by SEM and XRD analyzing. We carried out the experiment from sulfate Zinc bath containing sulfonated polyaniline, gelatin and thiourea by EG(Electrogalvanizing) simulator. Addition of polyaniline and gelatin in bath, crystal size and shape of hexagonal plane of Zn crystal reduced. Mixing of thiourea, however, brittle deposits were observed because of the difference between vertical growth and parallel growth. (1011) peak appeared with polyaniline and gelatin in XRD analysis. In case of mixing of polyaniline, gelatin and thiourea, (1011) peak appeared and intensity of Zn basal plane decreased. These results suggested that overpotential increased with addition of polyaniline and additives In bath.

아연 전기 도금 강의 환경친화적인 화성처리 기술 개발 (Development of chemical conversion coating technology by environment friendly method for Zn electroplated steel)

  • 김성종;김정일;장석기
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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    • pp.271-272
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    • 2006
  • Zinc confers high corrosion resistance by acting as a sacrificial anode, and a zinc coating improves the appearance of steel. Chromate conversion coating (CCC) films are still one of the most efficient surface treatments for steel. Although such films can self-repair via the dissolution of Cr(VI), dissolved Cr(VI) have adverse effects on humans, and the environment. Therefore, we examined the corrosion protection property and morphology of colloidal silica conversion films as an alternative to CCC films. The corrosion behavior was investigated in 3% NaCl solution using electrochemical techniques, including electrochemical impedance spectroscopy, open circuit potential, and the salt spray test(SST). Corrosion was implied by the appearance of red rust on the specimen surface. In corrosion resistance at 3% NaCl solution, red rust appeared at 15-20, 55-70, and 83-98 days on Zn-electroplated steel, colloidal silica conversion-coated specimens, and CCC-coated specimens, respectively. In the salt spray test, the colloidal silica film provided better corrosion protection than CCC films, i.e., red rust appeared at 96 hours on the Zn-electroplated steel sheet, at 432 hours with the CCC films, and at 888 hours with silica conversion coating.

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돼지감자 분말과 올리고당을 첨가한 머핀 제조의 최적화 (Optimization of Muffin preparation upon Addition of Jerusalem Artichoke Powder and Oligosaccharide by Response Surface Methodology)

  • 박금순
    • 한국식생활문화학회지
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    • 제29권1호
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    • pp.101-110
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    • 2014
  • This study was performed to determine the optimal composition of a muffin added with jerusalem artichoke powder and oligosaccharide. The experiment was designed based on CCD (central composite design), and evaluation was carried out by means of RSM (response surface methodology), which included 10 experimental points with three replicates each for the two independent variables jerusalem artichoke powder and oligosaccharide. The experimental muffin was prepared according to a traditional recipe, except that the flour was partially replaced by jerusalem artichoke powder (5, 15, or 25%) and the sugar was partially replaced by oligosaccharide (25, 50, or 75%). Using F-test, height, moisture, a-value, b-value, springiness, cohesiveness, texture, and overall acceptability were expressed as a linear model, whereas volume, pH, L-value, appearance, flavor and taste were expressed as a quadratic model. Increased amounts of jerusalem artichoke powder led to reduction of sensory scores for appearance, flavor, taste, texture, and overall quality. The optimum formulation determined by the numerical and graphical methods were similar: jerusalem artichoke powder 10.99%, oligosaccharide 71.40%.