• 제목/요약/키워드: Warm Pressing

검색결과 19건 처리시간 0.022초

온간 정수압 공정 조건에 따른 LTCC sheet의 수축률 (Influence of WIP conditions on dimensional change of LTCC sheet)

  • 정명식;윤여환;임성한;윤성만;오수익
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2008년도 춘계학술대회 논문집
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    • pp.507-511
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    • 2008
  • LTCC (Low Temperature Co-fired Ceramic) has been successfully applied to ceramic substrates for circuits and micro-fluidic systems and has proven its superior performance in a variety of applications. The prediction of shrinkage in LTCC process is an important for dimensional control of micro LTCC products which has influences on electronic characteristics. For avoiding the unpredictable shrinkage of LTCC during the sintering which makes accurate placement of the circuit devices difficult, pre-processes such as WIP (Warm Isostatic Pressing) and lamination must be modified. The objective of the present investigation is to establish a proper WIP conditions for near net shape fabrication of LTCC products. This paper discusses the influence of WIP conditions on the dimensional change of LTCC sheet. In the investigation, it is shown that the shrinkage values of sheets depend on WIP conditions and sheet directions. This work is a quantitative evaluation of the effect of WIP pressure on shrinkage of LTCC sheet. Additionally, the results show anisotropic shrinkage behaviour of sheet during LTCC process.

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정수압을 이용한 미세 패턴 전사 신공정 개발 (Development of New Micro Pattern Fabrication Process by U sing Isostatic Pressing)

  • 설재완;주병윤;임성한
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 추계학술대회 논문집
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    • pp.267-270
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    • 2009
  • In the present investigation, we are newly developing a new forming process which can fabricate micro patterns on large-area polymeric substrates for high speed mass production. The key idea of the new process is to pressurize multiple vacuum-packed substrate-mold stacks above the glass transition temperature ($T_g$) of the polymeric substrates. The new process is thought to be promising micro-pattern fabrication technique in three aspects; firstly, isostatic pressing ensures the uniform micro-pattern replicating condition regardless of the substrate area. Secondly, the control of forming condition such as temperature and pressure can realize well-defined process condition exploited in the conventional hot embossing research field. Thirdly, multiple substrates can be patterned at the same time. A prototype forming machine for the new process was developed with the design consideration realizing the present idea. With a developed machine, micro prismatic array patterns with 50 um in size were successfully made on the $380{\times}300{\times}6\;mm$ PMMA plate.

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The Research on Lighting Design of Parks

  • Zhang, Rui;Piao, Yong-Ji;Cao, Lin-Sen;Cho, Tae-Dong
    • 한국환경과학회지
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    • 제23권6호
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    • pp.1013-1020
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    • 2014
  • Based on the survey of the parks in Tai'an by questionnaire survey, on-the-spot investigation and in-depth interview, the paper analyzes the tendencies of visitors in modern landscape lighting design forms and methods from two terms: primary attributes and the preferences of artistic lighting design. To increase the safety of the parks is a pressing need for visitors. Visitors have a pressing need for increasing the safety of the parks' lighting and artistic quality. Most visitors think the parks' lighting has blind spots and the brightness is not enough. Visitors' night activities in the park will be insecure. As to artistry aspects, people prefer strong artistic style of lamps and lanterns to the common, such as ethnic style and animal image; Tourists prefer to use white light and yellow light to illuminate trees, because these colors make people feel more warm and amiable. This research provides basic data for lighting design of parks.

눈을 健康하게 하는 導引術 및 運動法에 대한 文獻的 考察 (A Literatur Review of Pysical and Breathing Exercises for Eye Health)

  • 송영림;노석선;임락철
    • 한방안이비인후피부과학회지
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    • 제10권1호
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    • pp.91-121
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    • 1997
  • These days many p대ple are disterbed from eyestrain and the number is on the increase. So, through the oriental and occidental books I studied pysical and breathing exercises to help overcome eyestrain. The result were as follows; 1. The most common way is to close your eyes and rub them with warm palms. Then press or rub your eyeballs simultaneously. 2. There are two ways to exercise the eyeball by itself. One way is by looking at only one spot and the other way is to look four ways-first up, down, left and right-and then rotate right and left. 3. There are many different opinions that of the degree of strenth to be used in pressing the eyeball. I came to the conclusion that if we want to relex the eyeball, you must press it gently but to strenthen it, you must press it hard. 4. This method is a common way to press orbit or acupuncture points of the peripheral eyeball. For example B-1(晴明), S-2(四白), B-2(찬죽), Tae-Yang(太陽), TE-23(絲竹空), etc. 5. Since eyestrain is related to the whole body, it is known that you can relex your whole body by pressing the acupuncture points located in the head and posteriores cerviicis or by stretching the upper half of the body. 6. The best time to pratice is early in the morning or when you feel eyestrain. But I couldn't find a consistent on breathing method or the amount of time to practice.

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耳의 導引術 및 運動法에 對한 文獻的 考察 (A Literatual Review of Physical and Breathing Exercises for Ear Health.)

  • 박세봉;김종한;고우신
    • 한방안이비인후피부과학회지
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    • 제11권1호
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    • pp.180-196
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    • 1998
  • A Literatur Review of Physical and Breathing Exercises for Ear Health, the results were as follows. 1. The most common using way is rubbing your ears and auricle with warm palms. 2. To stimulate inner acoustic meatus, obstruct external acoustic meatus for a short time by the palm or fingers and then to stimulate it by the sudden opening. 3. This method is a common way to press aurical or orifice of external acoustic meatus for example, TE21(耳門), TE20(角孫), GB2(聽會), TE19(노息), TE18(계脈), GB11(竅陰), TE17(예風) etc. 4. The best time to pratice is early in the morning or before go to bed, but a litter difference by the writer's opinion, so there is not consistency. 5. Since tinnitus and hardness of hearing is related to the who1e body, it is known that you can relax your whole body by pressing the acupuncture points located in the head of occipital region or by stretching the upper half of the body. 6. There is method that obstruct your ears with palms and 3rd finger on your occipital region and splash by the 2th fingers.(sound the celestial drum)

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Effects of cultivar and harvest days after planting on dry matter yield and nutritive value of teff

  • Saylor, Benjamin A;Min, Doohong;Bradford, Barry J
    • Journal of Animal Science and Technology
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    • 제63권3호
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    • pp.510-519
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    • 2021
  • One of the most pressing issues facing the dairy industry is drought. In areas where annual precipitation is low, irrigation for growing feed presents the greatest water-utilization challenge for dairy producers. Here, we investigated the effects of cultivar and harvest days after planting (DAP) on dry matter (DM) yield and nutritive value of teff (Eragrostis tef), a warm-season annual grass native to Ethiopia that is well adapted to drought conditions. Eighty pots were blocked by location in a greenhouse and randomly assigned to four teff cultivars (Tiffany, Moxie, Corvallis, and Dessie) and to five harvest times (40, 45, 50, 55, or 60 DAP). Cultivars had no effect on DM yield and nutritive value. As harvest time increased from 40 to 60 DAP, DM yield and ash-free neutral detergent fiber (aNDFom) concentrations increased, while crude protein (CP) concentrations and in vitro NDF digestibility decreased. To assess carryover effects of time of harvest on yield and nutritive value, two additional cuttings were taken from each pot. Increasing first-cutting harvest time decreased CP concentrations in the second cutting and reduced DM yields in the second and third cutting. Harvesting teff between 45 and 50 DAP best optimized forage yield and nutritive value in the first and subsequent cuttings.

닥나무의 인피섬유(靭皮纖維)를 이용(利用)한 전통(傳統) 한지장판지(韓紙壯版紙) 개발(開發)에 관(關)한 연구(硏究) (A Study on the Development of Traditional Korean Paper Changphanji by the Bast Fiber of Paper Mulberry)

  • 전철
    • Journal of the Korean Wood Science and Technology
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    • 제18권4호
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    • pp.53-64
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    • 1990
  • This study was carried out to develop the traditional korean paper changphanji from the bast fiber of paper mulberry The results obtained were as follows: 1. The variations in the basis weight were remarkable, but there were no significant adverse effects on the tensile strength and thickness. 2. The stamping have contributed to the improvement of smoothness and the control of thickness. The automatic pressing system recommended to obtain good control of thickness. 3. The average density of the traditional korean paper changphanji was 1.06g/$cm^3$. 4. The changphanji developed in this study gave a clude, but excellent toughness and warm feeling. Some fiber lumps, dark spots and bamboo, screen marks were also obserded. 5. The tensile strength of four-fold sheet changphanji is highest and those of two-fold sheet changphanji is lowest. the lengthwise tensile strength was higher than crosswise one due to the fiber. 6. The elongation of three-fold sheet changphanji was highest 7. The water absorption of all products ranged from 11.3g/$m^2$ to 17.5g/$m^2$. 8. The wight loss by abrasion was 34.0%(four-fold sheet) 31.6%(three fold sheet), 31.0% (two-fold sheet)respectively. 9. Based on the results obtained. tensile strength and elongation, the four-fold sheet was excellent. the use of the bast fiber of paper mulberry as a raw material is attractive point which can not obtained from the commercial changphanji made from other raw materials.

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리기다소나무 단판적층재(單板積層材)의 제조조건(製造條件)에 따른 물리적성질(物理的性質) 및 도장성능(塗裝性能) (Suitable Conditions of Producing the LVL from Pitch Pine and its Paint Film Durability)

  • 박상범;공영토;조재명
    • Journal of the Korean Wood Science and Technology
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    • 제17권1호
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    • pp.3-11
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    • 1989
  • 리기다소나무 단판적층재(單板積層材)(LVL)의 가구용재(家具用材)로서의 적합성(適合成) 여부(與否)를 판단(判斷)하기 위한 기초자료(基礎資料)를 제공(提供)하고자 요소 멜라민수지(樹脂)와 페놀수지접착제(樹脂接着劑)를 사용(使用)하여 단판적층재(單板積層材)를 제조(製造), 그 물리적(物理的), 기계적(機械的) 성질(性質), 접착내구성(接着耐久性) 및 제조성능(製造性能)을 검토(檢討)한 결과(結果)는 다음과 같다. 1. 리기다소나무 LVL 제조(製造)를 위한 적정압체시간(適正壓締時間)은 단판(單板)두께 1mm당(當) 45초(秒) 이상이 요구(要求)되었다. 2. 휨강도(强度)는 소재(素材)에 비(比)해 낮았으나 압축강도(壓縮强度)는 비슷하였고 단판(單板)의 두께가 얇을수록 강도(强度)는 증가(增加)하는 경향(傾向)이였다. 3. 충격(衝擊)휨흡수(吸收)에너지는 두께 2.5cm의 경우(境遇) 섬유직각방향(纖維直角方向)(상(上))이 $0.03kg{\cdot}m/cm^2$, 섬유방향(纖維方向)이 $0.24kg{\cdot}m/cm^2$으로 $0.68kg{\cdot}m/cm^2$인 소재(素材)에 비(比)해 매우 낮았다. 4. 열압체시간(熱壓締時間)을 45초(秒)/mm 이상(以上)으로 하면 침지박리(浸漬剝離) 및 한열반복시험시(寒熱反復試驗時), 접착층(接着層)의 박리(剝離), 표면할열(表面割裂), 부풀음, 변색(變色) 등(等)이 발생(發生)하지 않았다. 5. 진공침수시험(眞空侵水試驗)은 결과(結果), 섬유방향(纖維方向)으로서 수축율(收縮率)은 약(約) 1.0%, 섬유직각방향(纖維直角方向)(횡방향(橫方向))은 약(約) 3%였으며, 1~4개(個) 정도(程度)의 표면할제(表面割裂)이 관찰(觀察)되었다. 6. 온냉건고시험(溫冷乾燥試驗)에 의한 리기다소나무 LVL의 도막할열(塗膜割裂)은 전혀 관찰(觀察)되지 않았다. 7. 리기다소나무 LVL을 내장용(內粧用)으로 사용(使用)할 경우(境遇), 부착용화장단판(付着用化粧單板)으로서는 단판자체(單板自體)의 할열(割裂)이 적은 단판(單板)을 사용(使用)하여야 하며 부착용화장단판(付着用化粧單板)과 LVL의 표면(表面)이 서로 직교(直交)되도록 접착(接着)해야 표면할열(表面割裂)의 발생(發生)이 적고 표면부착성(表面付着性)이 향상(向上)되었다. 결론적(結論的)으로 리기다소나무 LVL은 접착성(接着性)은 매우 양호(良好)하였으며 휨강도(强度), 압축강도(壓縮强度) 및 충격(衝擊)휨흡수(吸收)에너지 등(等)은 가구재료(家具材料)로써 적정수준(適正水準)이었으나 단판자체(單板自體)의 옹이 및 할열(割裂)로 인(因)해 가구재료(家具材料)로 사용(使用)할 경우(境遇), 품질(品質)이 좋은 단판(單板) 즉, 화장단판(化粧單板) 등(等)으로 표면(表面)해양 할 것으로 생각되었다.

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