• Title/Summary/Keyword: dry temperature

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Formation of Fine Pitch Solder Bumps on Polytetrafluoroethylene Printed Circuit Board using Dry Film Photoresist (Dry Film Photoresist를 이용한 테프론 PCB 위 미세 피치 솔더 범프 형성)

  • 이정섭;주건모;전덕영
    • Journal of the Microelectronics and Packaging Society
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    • v.11 no.1
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    • pp.21-28
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    • 2004
  • We have demonstrated the applicability of dry film photoresist (DFR) in photolithography process for fine pitch solder bumping on the polytetrafluoroethylene (PTFE/Teflon ) printed circuit board (PCB). The copper lines were formed with 100$\mu\textrm{m}$ width and 18$\mu\textrm{m}$ thickness on the PTFE test board, and varying the gaps between two copper lines in a range of 100-200$\mu\textrm{m}$. The DFRs of 15$\mu\textrm{m}$ thickness were laminated by hot roll laminator, by varying laminating temperature from $100{\circ}C$ to 15$0^{\circ}C$ and laminating speed from 0.28-0.98cm/s. We have found the optimum process of DFR lamination on PTFE PCB and accomplished the formation of indium solder bumps. The optimum lamination condition was temperature of $150^{\circ}C$ and speed of about 0.63cm/s. And the smallest size of indium solder bump was diameter of 50$\mu\textrm{m}$ with pitch of 100$\mu\textrm{m}$.

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Spatio-temporal Distribution of Organic Matters in Surface Sediments and Its Origin in Deukryang Bay, Korea (득량만 표층퇴적물 중 유기물의 시.공간적 분포 및 기원)

  • 윤양호
    • Journal of Environmental Science International
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    • v.12 no.7
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    • pp.735-744
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    • 2003
  • The field observations on a seasonal characteristic of organic matter and its origin in the surface sediment were carried out at 35 stations in Deukryang bay, southern coast of Korean Peninsula from May 1995 to February 1996. The analytical parameters were mud temperature, ignition loss(IL), chemical oxygen demand(COD), pheopigment, sulfide and water content. The origin and seasonal dynamics of organic matter in Deukryang Bay were analyzed by COD/IL, COD/sulfide ratio and principal component analysis(PCA). As a results of the mud temperature fluctuated between 2.1$^{\circ}C$ with the lowest mean 4.6$^{\circ}C$ in winter and 27.6$^{\circ}C$ with the highest mean 25.5$^{\circ}C$ in summer. The range of ignition loss(IL) was from 3.1% in autumn to 21.5% in winter. Chemical oxygen demand(COD) showed the highest mean value of 8.45 mg/g dry in spring within the range of 2.90∼18.21 mg/g dry, while it showed the lowest value of 4.33 mg/g dry in autumn within the range of 0.67∼10.37 mg/g dry. Pheopigments showed the highest mean value of 9.04 $\mu\textrm{g}$/g dry in autumn within the range of 1.36∼20.44 $\mu\textrm{g}$/g dry, while it did the lowest mean value of 2.20 $\mu\textrm{g}$/g dry in summer within the range of 0.33∼11.36 $\mu\textrm{g}$/g dry. The range of total sulfide (H$_2$S) was from no detect(ND) to 3.30 mg/g dry in spring. And water content showed the annual mean value of 43.6% within the range of 23.6∼54.9%. The source of organic matter by COD/IL and COD/sulfide ratio in Deukryang Bay had been producted by primary producer in sea water areas except the areas effected by small stream, domestic and animal wastes. And the analytical results of PCA was able to be divided into three different regions. The former was characterized by the shallow depth and authigenic organic matter from phytoplankton in northwest area and northeastern inner bay, the secondary was done by deeper depth and allochthonous one from lands in southeast area and eastern entrance of bay, and the latter was done by authigenic one from the farm of seaweeds such as, sea cabbage, sea mustard etc in western entrance of bay. But a study on the relationship between sulfide and COD concentration in the northeastern inner bay which was characterized by the water stagnation will to take much more studying including major constituents of organic matter in the future.

Analysis of Cooling Effect on the Plastic Film Cover of Greenhouse Module Depending on the Shade and Water Curtain (온실지붕 차광과 수막 수준에 따른 냉방효과 분석)

  • Kim, Young-Bok;Park, Joong-Chun;Lee, Seung-Kyu;Kim, Sung-Tae;La, Woo-Jung;Huh, Moo-Ryong;Jeong, Sung-Woo
    • Journal of Bio-Environment Control
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    • v.15 no.4
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    • pp.306-316
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    • 2006
  • In this study, the effect of the shade level, water flow rate applied to the shades and the temperature of water on the greenhouse cooling was investigated depending on the shade level of 0, 35, 55, 75%, and water flow rate and water temperature by the test on the small wooden frames to find out the low cost cooling method. With increasing of the dry bulb temperature of outside air, the dry bulb temperature in the wooden frames increased. For the frames with the shade and water, inside temperatures of the frames were lower of -0.2$\sim$-1.2$^{\circ}C$ than the temperature of the outside air and higher than the water temperature. For the frames without water, inside temperatures of the frames were higher of 1.7$\sim$4$^{\circ}C$ than the outside and not affected by the shade level very much. The water flow rate and the temperature of the water were not the important factors to decrease the inside temperatures in the frames. The black globe temperature became lower with increasing of shade level. The shade frames with water curtain showed the best cooling effect because of reducing thermal radiation and cooling the plastic film cover. The surface temperatures of the plastic film cover for the water supplied modules became lower with increasing of the shade level. The relative humidity was decreased with the dry bulb temperature in the frame increasing and not affected by the dry bulb temperature of the outside air for the frames with the shade and water.

Thermal Comfort Condition of Temperature and Humidity in Loess Interior Space

  • Kong, Sung-Hoon
    • Biomedical Science Letters
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    • v.10 no.2
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    • pp.129-135
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    • 2004
  • The study was carried out through measuring the temperature and humidity of the indoor/outdoor space and the distribution of interior thermal condition, and investigating the effect of loess materials on human body. The purpose of this study is to analyze the change of dry bulb temperature and relative humidity and correlation of thermal reaction of human body with ASHRAE (American Society of Heating, Refrigerating and Air-conditioning) comfort chart in the loess interior space. In the view point of biomedical sciences, loess interior space provides optimum thermal conditions for human thermal sensation.

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Drying characteristics of mulberry fruit according to storage condition using far-infrared ray dryer for the production of semi-dried mulberry fruit

  • Kim, Hyun-bok;Ju, Wan-Taek;Sung, Gyoo Byung;Lee, Myeong-Lyeol;Seo, Sang-Deok
    • International Journal of Industrial Entomology and Biomaterials
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    • v.35 no.1
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    • pp.45-50
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    • 2017
  • Using the relatively low-cost, far-infrared dryer inhibiting the destruction of a variety of physiologically active components of the mulberry fruit, we have studied to make semidry mulberry fruit that can be kept at room temperature for a long time. By adjusting the temperature of the far-infrared dryer step-by-step, we developed a semi-dry method of maintaining the shape of the mulberry fruit. In addition, by drying the coating of honey after removing the juice generated by the mulberry fruit thawing process improved the acceptability of the taste of fruit. We conducted heat treatment mulberry fruit into a $95^{\circ}C$ infrared dryer 5 hours to thaw the frozen mulberry fruit. After 10 to 20% of honey coating, the primary drying ($95^{\circ}C$, 5 hours) was implemented. then, the secondary drying was conducted after controlling the temperature of the far infrared dryer $60^{\circ}C$, for 10 hours. These manufacture process was able to obtain semi-dried mulberry fruit. Dry weight ratio and moisture content were around 25%, and around 16% level respectively. It was to enable long-term storage at room temperature. Therefore, it is suggested that the method of using the far-infrared drying machine to manufacture semi-dried mulberry fruit can be a way to improve the farm income if applied to the farm.

Determination of Critical Early Seeding Date for Seedling Emergence in Dry-Seeded Rice Based on Statistical Analysis of Daily Mean Air Temperature in Korea (일평균기온의 지역별 출현특성 분석에 의한 벼 건답직파 출아조한의 파종기 결정)

  • 최돈향
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.39 no.5
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    • pp.437-443
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    • 1994
  • Appearance characteristics based on the daily mean air temperature (DMAT) were evaluated to obtain the fundamental data for the safety of dry-seeded rice under the local climatic conditions. The climatic data of 56 meteorological stations throughout Korea were applied for determination of the effective standard temperature at the emergence. The first appearance date at the DMAT 1$0^{\circ}C$ was found to be 20~30 days (standard deviation: 5~7 days) for year fluctuation and 4\geq$30 days for regional change in Pusan and Taegwallyong. Mean appearance date of it, also, was 10 days earlier than that of its 80% chance. Seeding date at the early critical seedling emergence was April 11 for Suwon, March 31 for Kwangju, April 1 for Taegu and April 7 for Kangnung.

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Effect of Ceramics in the Nutrient Solution on the Growth of Chinese Flat Cabbage (양액내 세라믹 처리가 청경채의 생장에 미치는 영향)

  • 박병모;권성환;박학봉
    • Journal of Bio-Environment Control
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    • v.6 no.2
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    • pp.117-122
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    • 1997
  • The effect of ceramics in the nutrient solution on the growth of Chinese flat cabbage(Brassica campestris L. var. Tacai) was studied at the favourable root temperature of 3$0^{\circ}C$ and at the greenhouse air temperature of fixed $25^{\circ}C$. Ceramic No. 2 was produced the greatest dry weight, while ceramic No. 3 was lower productive than those of untreatment in each root temperature. Shoot/root dry weight ratio was reduced at treatments with ceramics, which may be explained by rich root growth, and it increased as raising the temperature from 25 to 3$0^{\circ}C$ or 35$^{\circ}C$. The treatments of ceramics made lower water content/dry weight($m\ell$/g) ratio of Tacai than untreatment. The electrical conductivity and inorganic matters of ceramics were low level(EC 0.001 -0.03mS/cm). Also, the blue ceramic No. 3 of them had strong antibacteria in LB medium and ceramic treatments was inhibited the rot of solution.

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Comparison of Physicochemical Properties of Starch Phosphates Prepared by Dry Heating and Extrusion Process (건식법과 Extrusion 공정에 의해 제조한 인산전분의 이화학적 성질 비교)

  • Kim, Chong-Tai;Ryu, Gi-Hyung;Kim, Dong-Chul;Kim, Chul-Jin
    • Korean Journal of Food Science and Technology
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    • v.22 no.6
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    • pp.651-658
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    • 1990
  • Starch phosphates were prepared by dry heating, gelatinizing method and extrusion process using sodium tripolyphosphote (STPP) as a substitution reagent and their physicochemical properities were compared. In the preparation of starch phosphate by dry heating method(DSP), the effect of reaction temperature was the most significant to the DS(Degree of substitution). In the phosphorylation reaction with gelatinized starch(GSP), the substitution ratio was increased with increasing the reaction temperature, but the increase was insignificant above $85^{\circ}C$. By extrusion with the corn starch containing 2.0% STPP at various moisture contents of 20, 25 and 30%, the DS values of extrudate(WESP) were within the range of between 0.0066 and 0.0083. The starch phosphate(DSP) products showed lowering the gelatinization temperature, increasing the clarity of the starch paste. However, WESP showed higher gelatinization temperature than that of raw starch. The starch phosphate prepared by extrusion process showed lower apparent viscosity of paste than that of the DSP at same condition. All of starch phosphates showed reducing the tendency of the paste retrogradation.

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Effect of Aeration Rates on Ammonia Emissions during Composting of Livestock Manure (축분(畜糞) 퇴비화시(堆肥化時) 공기주입율(空氣注入率)이 암모니아 배출(排出)에 미치는 영향(影響))

  • Kang, Hong-Won;Rhee, In-Koo;Park, Hyang-Mee;Ko, Jee-Yeon;Choi, Jyung
    • Korean Journal of Soil Science and Fertilizer
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    • v.32 no.3
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    • pp.304-311
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    • 1999
  • This experiment was conducted to find out the optimum condition of aeration rates for removal of malodor and to improve the compost quality. The aspect of ammonia emission and amounts of volatilization were investigated in the enclosed composting reactor of 242 liters piled with mixed materials of dairy manure and rice straw, which adjusted to 65% of initial moisture content and controlled by four different aeration rates. Mature temperature increased suddenly in initial composting time and decreased with Increasing aeration rates. The treatment of $1.79l\;min^{-1}kg\;dry-solids^{-1}$ results in overcooling and rapid drying of composting materials because of too much aeration. The average concentration of ammonia emitted from composting for 24 days was the range of 25.3 to $239.8mg\;l^{-1}$ and was highest in the treatment of $0.09l\;min^{-1}kg\;dry-solids^{-1}$, followed by 0.90. 0.18 and $1.79l\;min^{-1}kg\;dry-solids^{-1}$. The range of maximum concentration by different aeration rates was $335{\sim}2279mg\;l^{-1}$ and it wan highest in the treatment of $0.09l\;min^{-1}kg\;dry-solids^{-1}$, followed by 0.18, 0.09 and $1.79l\;min^{-1}kg\;dry-solids^{-1}$. Relationship between the ammonia concentration emitted and temperature matured under different aeration rates showed an exponential positive correlation with 1% significance and had a trend of clear increase in ammonia concentration with increasing temperature over $50^{\circ}C$. Most of ammonia volatilized within plays after composting. The volatilization rate of ammonia ranged from 0.056 to 0.453 per dry solids of materials and it was highest in the treatment of $0.09l\;min^{-1}kg\;dry-solids^{-1}$, followed by 0.18, 0.09 and $1.79l\;min^{-1}kg\;dry-solids^{-1}$. Amounts of ammonia volatilized under composting condition of this experiment was estimated to be highest in the aeration range of 0.9 to $1.0l\;min^{-1}kg\;dry-solids^{-1}$.

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The Influence of Office Indoor Air Qualitys on the Dry Eye Symptom of Contact Lens Wearers (사무실 실내공기질과 콘택트렌즈 착용여부가 안구 건조증에 미치는 영향)

  • Kim, Dea Jong;Park, Moon Chan;Lee, Se Hoon;Kim, Hyun Uk;Lee, Wha Ja;Cha, Jung Won
    • Journal of Korean Ophthalmic Optics Society
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    • v.17 no.2
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    • pp.215-222
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    • 2012
  • Purpose: This study was performed to investigate the influence of indoor air qualities of an office environment on dry eye syndrome for wearing contact lens and non-wearing contact lens. Methods: To study the effects of indoor air qualities on dry eye syndrome for seventy-one subjects, $CO_2$, temperature, humidity, TSP, PM10, HCHO were measured. Each subject was tested by a McMonnie's dry eye syndrome questionnaire, a Schirmer Tear Test-I (S.T.T-I), a Schirmer Tear Test-II with anesthetics (S.T.T-II), and Tear film break-up time (T.B.U.T) in the their offices. Results: There was significant relation between the indoor air quality and dry eye syndrome for wearing contact lens and non-wearing when TSP was over $200{\mu}g/m^3$, PM10 was higher than $86.7{\mu}g/m^3$ and Formaldehyde was over $0.4{\sim}1.0{\mu}g/m^3$. However, there was no significant effect on dry eye syndrome with $CO_2$ (p=.0146), temperature (p=0.074) and humidity (p=0.053). Conclusions: It was indicated that $CO_2$, temperature and humidity were no effect on dry eye syndrome in the office environment. However TSP, PM10, formaldehyde, and wearing contact lens were effect on dry eye syndrome. Therefore, the entire management of wearing contact lens and the individual evaluation of the indoor air quality are required.