• 제목/요약/키워드: worn surface

검색결과 288건 처리시간 0.024초

독일 상트 오틸리엔 선교분도수도원 선교박물관 소장 갑옷에 관한 기초연구 (A Fundamental Study of the Armors of the Missionsmuseum St. Ottilien in Germany)

  • 조우현;염정하
    • 복식
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    • 제65권3호
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    • pp.76-90
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    • 2015
  • This is a basic study of the two remaining armors (artifacts number K2366, K2368) from the late Joseon dynasty that is part of the Korean costume collection, which is preserved in the Mission Museum of Saint Ottilien in Germany. The armor No. 1 (artifacts number K2366) is a coat-styled armor with brass studs. It has a U-shaped neckline with the non-overlapping collars and sleeve straight-lined inseam. The armor No. 1 has the Mu to the sides and is not back slit. Both its inner and outer material are padded with cotton. Leather mails are attached on the inner lining, and studs are attached on the outer lining to match the leather mails. For this reason, the armor No. 1 can be named MyeonPiGab (brass studded armor consisting of a cotton coat with internal leather mails). The outer material is faded to have the natural white, or antique white look and the patterns on it are indigo blue. The inner material is blue, but the original color is unknown since it is faded. The lotus blossoms and vine patterns are dyed on the surface of the outer material and a name is written on the inner material. The armor No. 1 was worn between the late 17th century and the 19th century. It is estimated that it was worn by military officers who were above the mid-rank in the end of the Joseon dynasty. The armor No. 2 (artifacts number K2368) is a coat-styled armor with brass studs and a low-cut U-shaped neckline. The armor No. 2 has a slit on the left armpit and a string around it. Studs are evenly attached on the armor. The iron mails are attached to the left chest area on its inner lining. It seems that it was designed with both formality and functionality in mind. The outer material is red flannel, the inner material is blue satin and the pads are cheesecloth. The side of its collars, cuffs, front lines, sidelines, back slit, and bottom lines are trimmed with fur. There are armors called "JeonCheolGap (brass studded armor consisting of a felt coat with internal iron mails)," which is similar to the armor No. 2, however, the similarities are limited because they are not made of the same material nor do they follow the same principle of nomenclature.

잠사회사(蠶絲會社) 여공(女工)의 피부질환(皮膚疾患) (Skin Diseases of Female Workers in Silk Reeling Industry)

  • 김두희
    • Journal of Preventive Medicine and Public Health
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    • 제9권1호
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    • pp.117-122
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    • 1976
  • 잠사회사(蠶絲會社) 근로자(勤勞者)의 직업성질환(職業性疾患)을 분석해 보기 위하여 1975년(年) 11월(月) 근로조건(勤勞條件)이 같은 대구시내(大邱市內) 모잠사회사(某蠶絲會社) 여자근로자(女子勤勞者) 177명(名)에 대하여 집단건강진단시(集團健康診斷時) 시진(視診)에 의하여 실시(實施)한 결과 다음과 같이 요약할 수 있었다. 전(全) 여자근로자(女子勤勞者)에 있여서 각종피부질환(各種皮膚疾患)의 유병률(有病率)이 53%로 반수(半數)이상에 달하여 피부질환(皮膚疾患)은 대체(大體)로 3가지로 대분(大分), 손톱마모(磨耗), 피부(皮膚)의 각화, 나류(裸瘤), 구열(龜裂) 등과 같은 피부변화(皮膚變化)(47.5%)가 가장 많으며 알레르기 반응(反應)(14.7%)과 기타 무좀 등의 순이었다. 피부변화(皮膚變化)는 그 진행정도(進行程度)의 차이(差異)가 있었으나 대개 복합적(複合的)으로 발생(發生)하여 근속년수와는 무관한 것 같으나 대체적으로 2년이상 근속자에게 빈발하는 경향을 보이며 손톱마모(磨耗)는 이에 따라 현저(顯著)한 차이(差異)를 보이고 있다. 알래르기 반응(反應)은 입사후(入社後) 수개월 이내에 발생(發生)하며 다시 접촉 여하에 따라 그 정도로 달라지게 되는 것 같다. 계속 근무자보다 과거에 경험한 바 있는 자에서 다소 그 빈도가 높은 경향을 보여 준다. 호발부위(好發部位)는 역시 접촉이 잦은 손가락부터 손바닥, 손, 팔, 다리, 얼굴, 목, 몸통등 광범하게 번져가며 심한 경우 습진 양으로 변해 가고 있다.

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다이아몬드 코팅 와이어로 가공된 태양전지용 실리콘 웨이퍼의 표면 특성에 관한 연구 (A study on the surface characteristics of diamond wire-sawn silicon wafer for photovoltaic application)

  • 이경희
    • 한국결정성장학회지
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    • 제21권6호
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    • pp.225-229
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    • 2011
  • 현재 결정질 태양전지에서 웨이퍼 가공은 대부분 슬러리 분사 방식의 다중 와이어를 이용한 방법이 사용되고 있다. 이와 같은 슬러리 분사 방식의 웨이퍼 가공은 가공속도가 낮아 생산성이 떨어지는 단점이 있을 뿐만 아니라 금속 재질의 와이어와 실리콘 블록의 직접적인 마찰에 의하여 웨이퍼 표면의 금속 불순물에 의한 오염이 발생되는 단점이 있다. 뿐만 아니라 와이어와 실리콘 블록간의 직접적인 마찰로 인하여 와이어가 빨리 마모되며, 이로 인하여 일회성의 와이어를 사용하게 되면서 제조원가는 상승하게 된다. 반면에 다이아몬드 입자가 코팅된 와이어를 이용하여 실리콘 웨이퍼를 가공하게 되면, 가공속도가 기존 슬러리 분사방식보다 빠르며, 공정진행에 따른 와이어의 마모율이 적어 와이어의 재사용에 의한 제조원가 절감이 가능하다. 따라서 이와 같은 다이아몬드 입자가 코팅된 와이어를 이용하여 가공하는 기술은 슬러리 분사방식에 비하여 더 효율적이라 할 수 있다. 본 연구에서는 슬러리 분사방식으로 가공된 웨이퍼와 다이아몬드 코팅된 와이어로 가공된 웨이퍼의 표면특성에 대하여 분석하고 셀 공정에 영향을 미치는 것에 대하여 설명하고자 한다. 또한, 다이아몬드 와이어로 가공된 웨이퍼를 활용하기 위한 셀 공정의 개선방향에 대하여 제안하고자 한다.

임플란트 피개의치를 위한 개별유지형 어태치먼트의 유지력에 관한 연구 (A Study on the Retentive Force of Stud Attachments for Implant Overdenture)

  • 송은주;배은빈;최재원;배지현;김지영;이소현
    • 치위생과학회지
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    • 제16권1호
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    • pp.93-100
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    • 2016
  • 이번 연구에서는 두 종류의 어태치먼트 시스템인 Kerator와 O-ring의 다양한 유지력을 가지는 matrix를 사용한 반복적인 착탈 후 평가를 통해 다음과 같은 결론을 얻었다. 초기 유지력은 KP군($62.09{\pm}6.00N$)에서 높았으며, 이어서 KR군($32.83{\pm}4.40N$), KB군($12.69{\pm}3.32N$), OO군($9.55{\pm}1.33N$), 그리고 OR군($9.35{\pm}0.71N$) 순으로 나타났다. 유지력 소실량은 KP군($22.26{\pm}8.02N$)에서 가장 높았으며, KR군($6.23{\pm}3.04N$), OO군($6.03{\pm}1.24N$), OR군($5.81{\pm}0.73N$), 그리고 KB군($0.87{\pm}1.46N$) 순으로 나타났다. 각 군 내의 초기 유지력과 2,500회의 착탈 후의 최종 유지력을 비교하였을 때, KB군을 제외한 모든 군에서 유의한 차이를 보였다(p<0.05). 어태치먼트 표면 마모양상은 Kerator와 O-ring의 matrix에서 눈에 띄는 변형과 손상이 관찰되었다. 각 patrix에서는 유지력 소실에 기여할 만한 변화는 관찰되지 않았다. 결론적으로 어태치먼트의 종류, 재료 그리고 초기 유지력 차이에 따라 마모양상이나 유지력 소실에 차이가 있음을 확 인하였고, 유지력이 보존되는 것처럼 보여도 SEM으로 관찰하였을 때 어태치먼트의 내부가 상당히 변형된 경우가 많았다. 따라서 적절한 유지력을 가진 어태치먼트를 선택하고 각 어태치먼트 시스템 별 적절한 교체시기를 숙지하여 그에따른 사용기간의 준수가 필요할 것으로 생각된다.

가상 착의 시뮬레이션을 이용한 래글런 소매 패턴 변화에 따른 착의 시 정량적 분석 가능성 모색 (A Study on Based on the Possibility of Quantitative Analysis using Virtual Clothing Simulation according to Raglan Sleeve Pattern Types)

  • 이예진;이병철
    • 한국생활과학회지
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    • 제21권2호
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    • pp.299-314
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    • 2012
  • The purpose of this study was to explore effects of pattern alteration using a virtual clothing simulation approach in combination with 3D analysis software. Three raglan sleeves of different patterns were worn by an avatar using virtual clothing simulation with silk and cotton as the test fabrics. It was observed that the silhouette and hemline shape were affected differently based on raglan sleeve pattern and fabric type. By examining clothing pressure distribution, the cotton fabric designs and pattern shapes provided for a variety of influences on armhole and bust regions as well as the back sleeve area. For representative locations, cross section circumstance, cross section area, and volume were measured by using 3D analysis and the resulting correlation between the 2D and 3D data were investigated. Among different fabrics, there was little difference between the 2D and 3D clothing surface area. However, when using 3D analysis, clothing volume was significantly affected by different fabrics and pattern types. By simultaneously adopting the virtual simulator and 3D analysis, quantitative assessment of virtual clothing simulation was successfully conducted. In light of the results of this study, the resulting methodology is expected to be used as a comprehensive evaluation tool for virtual clothing simulation wear testing.

알루미나와 탄소단섬유를 혼합한 금속복합재료의 기계적 성질과 고체윤활 마모거동 (Mechanical Properties and Solid Lubricant Wear Behavior of MMCs Reinforced with a Hybrid of $Al_{2}O_{3}$ and Carbon Short Fibers)

  • 송정일;봉하동;한경섭
    • 대한기계학회논문집
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    • 제19권4호
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    • pp.968-980
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    • 1995
  • Al/Al$_{2}$O$_{3}$/C hybrid metal matrix composites are fabricated by the direct squeeze infiltration method. From the microstructure of Al/Al$_{2}$O$_{3}$/C composites, uniform distribution of reinforcements and good bondings are found. Optimum processing conditions for preforms and squeeze castings are suggested. Mechanical properties, such as elastic modulus, elongation, 0.2% offset yield strength and ultimate tensile strength are obtained. Through the abrasive were test and wear surface analsis, wear behavior and its mechanism of AC2B aluminum and Al/Al$_{2}$O$_{3}$/C composites can be characterized under various sliding speed conditions. Tensile strenght elongation of Al/Al$_{2}$O$_{3}$/C composites are decreased with increasing the addition of carbon fiber. On the contrary, elastic modulus of Al/Al$_{2}$O$_{3}$/C composites is slightly improved compared with that of the unreinforced matrix alloy. The addition of carbon fiber to al/al$_{2}$O$_{3}$/C composites gives rise to improvement of the wear resistance. Specially, carbon chopped fibers play an important role in interfering sticking between the counter material and metal matirix composites. Al/Al$_{2}$O$_{3}$/C composites are suitable to high speed due to solid lubication of carbon. And wear model of Al/Al$_{2}$O$_{3}$/C composites is suggested by the examination of worn surfaces.

수종 치주큐렛의 작업측 마모도의 비교연구 (Evaluation of Wear of Periodontal Curet's Lateral Surface in Working-end)

  • 신동환;임성빈;정진형
    • Journal of Periodontal and Implant Science
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    • 제29권3호
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    • pp.703-715
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    • 1999
  • The purpose of this study was to evaluate the degree of wear of periodontal curet's cutting edges made by three different manufacturers. In the first case of the experiment, this study was done with each new curett in the following three experiment. Twelve new double-ended No. 11/12 Gracy curettes from three different manufacturers (A, B and C) was randomly selected from our stock at first test. They were weared by wear tester with fixed pressure and limited distance. This study measured the width of worn curettes'cutting edge. The results were as follows ; 1)In 50 times experiment, this study discoverd that each manufacturer's curette was appeared with different degree of wear (p<0.01) 2)In 100 times experiment, this study result similarly to the 50 times experiment(p<0.01). 3)In 150 times experiment, the result of this study were alike as the X50 experiment and X100 experiment. In the second case of the experiment, the study was done with a curett of a manufacturer in the following three experiment. Two double-ended No. 11/12 Gracy curette from three different manufactures (A, B and C) was randomly selected from our stock at second test. 1)In 50 times experiment, this study discovered that each manufacturer's curette was appeared with different degree of wear (p<0.05). 2)In 100 times experiment, the result was same, compared with the 50 times experiment. 3)In 150 times experiment, this study also discovered that the result was same with the result of the upper two cases. In conclusion, this study discovered that the two cases of experimental were shown with a same result.

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치외치로 인한 봉와직염 환자에서 MTA를 이용한 치험례 (MTA APPLICATION TO PATIENTS WITH CELLULITIS CAUSED BY DENS EVAGINATUS)

  • 구정은;백광우
    • 대한소아치과학회지
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    • 제36권2호
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    • pp.310-317
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    • 2009
  • 치외치는 치아의 교합면에 부가적인 교두나 돌기(tubercle)를 가진 치아의 형태 이상이다. 치외치는 1-4%의 유병율을 보이며 하악 소구치에서 발생 빈도가 높다 치외치의 돌기는 쉽게 마모되거나 파절되어 치수 노출, 치수 생활력 상실, 안면부 감염, 골수염 등을 일으킬 수 있다. 또한, 돌기가 파절될 때 치외치의 치근단이 미성숙 상태인 경우가 많아 근관 치료가 쉽지 않다. 미성숙 영구치의 근관치료 시 수산화칼슘이 널리 사용되어 왔으나 내원 빈도 단축을 위해 여러 대체 재료들이 제안되어 왔다. 그 중 하나인 Mineral Trioxide Aggregate는 우수한 생체적합성과 변연 폐쇄성을 특징으로 하며, 미성숙 영구치의 근관치료 시 치료 기간을 단축시킬 수 있다. 본 증례보고에서는 치외치로 인한 치수 괴사로 봉와직염이 발생한 환자를 Mineral Trioxide Aggregate로 치료하였다. 미성숙 치근단을 가진 하악 소구치에 Mineral Trioxide Aggregate를 이용한 치근단형성술(apexification)을 시행하여 임상적 및 방사선학적으로 양호한 결과를 얻었으며, 한 증례에서는 치근단유도술(apexogenesis)의 결과와 같이 계속적인 치근 성장이 관찰되었다.

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정수장의 노후 급속 모래여과지 진단 및 개량 (Diagnosis and Renovation of a Time-worn Rapid Sand Filter used for Drinking Water Treatment)

  • 김상구;박현석;손희종;이정규;류동춘;유평종
    • 한국환경과학회지
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    • 제25권7호
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    • pp.999-1005
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    • 2016
  • The H water treatment plant has been operating since 1982 and has had no renovation. It is assumed that the filters have been operated for more than 30 years and therefore are deteriorated. Many of the filters show an unequal state of air scouring during backwashing. For this study one filter, which was presumed most deteriorated among eighteen filters, was selected as a model filter for renovation. Some of the effects seen after renovation of the underdrain system were a lower average filtrated turbidity by approximately 0.02 NTU and an equal backwash state throughout the filter bed. Sand wash efficiencies by backwash before renovation of the underdrain system were 28%, 8%, and 5% at the surface, 50 cm depth, and 100 cm depth, respectively, and after renovation of the underdrain system were 94%, 26%, and 15%, respectively. The standard deviation of the effective sand size was 0.025-0.033 mm before renovation of the underdrain system and 0.002-0.011 mm after renovation of the underdrain system, meanings there was equal backwash pressure throughout the filter. Filtration time after renovation was approximately 2 times longer than before renovation.

Halogen Light Curing Unit과 Light Emitting Diodes Curing Unit을 이용하여 중합되어진 복합레진의 마멸 특성 비교 (Wear of Resin Composites Polymerized by Conventional Halogen Light Curing and Light Emitting Diodes Curing Units)

  • 이권용;김환;박성호;정일영;전승범
    • Tribology and Lubricants
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    • 제21권6호
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    • pp.268-271
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    • 2005
  • In this study, the wear characteristics of five different dental composite resins cured by conventional halogen light and LED light sources were investigated. Five different dental composite resins of Surefil, Z100, Dyract AP, Fuji II LC and Compoglass were worn against a zirconia ceramic ball using a pin-on-disk type wear tester with 15N contact force in a reciprocal sliding motion of sliding distance of 10mm/cycle at 1Hz under the room temperature dry condition. The wear variations of dental composite resins were linearly increased as the number of cycles increased. It was observed that the wear resistances of these specimens were in the order of Dyract AP > Surefil > Compoglass > Z100 > Fuji II LC. On the morphological observations by SEM, the large crack formation on the sliding track of Fuji II LC specimen was the greatest among all resin composites. Dyract AP showed less wear with few surface damage. There is no significant difference in wear performance between conventional halogen light curing and light emitting diodes curing sources. It indicates that a light emitting diodes (LED) source can replace a halogen light source as curing unit for composite resin restorations.