• Title/Summary/Keyword: Dry condition

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A study on indoor environmental elements of the granite model dome in different envelope materials during summer season (하절기, 석재 모형돔의 외피 유형별 실내환경 요소에 관한 연구)

  • 공성훈
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.6
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    • pp.898-902
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    • 1999
  • During summer season, the weather condition of Korea is hot and humid. So humidity elements are very important relating to building envelope condition. The purpose of this investigation is to measure and analyze characteristics of summer's environmental elements such as relative humidity, dry bulb temperature and air velocity in the clay/cement envelope materials using a granite dome model. According to the variation of exterior humidity, the state of interior relative humidity for clay model has an equal tendency, although a little range of variation is shown in comparison to the cement model.

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Strengths and Corrosion-Inhibition of Epoxy-Modified Mortars Contaning Nitrite-Type Hydrocalumite (에폭시수지와 아질산형 하이드로칼루마이트를 병용한 폴리머 시멘트 모르타르의 강도 및 방청성)

  • Kim, Joo-Young;Kim, Wan-Ki
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2013.05a
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    • pp.53-55
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    • 2013
  • Nitrite-Type hydrocalumite (calumite) is a material that can provied a self-corrosion inhibition function to the reinforce concrete. In this study, bisphnol A·F type epoxy-midified mortars without hardner contaning calumite is prepared with various polimer-binder ratios, calumite contents and tow types of curing condition, and tested for flexural and compressive strength tensile strength and corrosion-inhibition. As a result, in the case of wet/dry curing condition, strengths of bisphnol A·F type epoxy-modified mortars without hardener contaning calumite is inclined to decrease with increasing of polymer-binder ratio and calumite content. However, dry cured specimens are slightly improved by using bisphnol A·F type epoxy resin. Finally, regardless of polymer-binder ratios and calumite contents, corrosion-inhibition of bisphnol A·F type epoxy-modified mortars without hardener containing calumite is superior than that of unmodified mortar.

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The Electrical Breakdown Characteristics of Broken Toughened Glass Stem Insulator (장간유리애자 파손시 절연파괴 특성)

  • Jung, Jong-Wook;Jung, Jin-Soo;Kim, Young-Seok
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.8
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    • pp.1398-1406
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    • 2008
  • This paper describes the electrical breakdown characteristics of broken toughened glass stem insulators by comparing with those of sound ones. The broken toughened glass stem insulators were taken from the electric railway field. According to the international standards, the sound and broken toughened glass stem insulators were tested in electrical strength. In the test, the power frequency voltage and the impulse voltage with a standard waveform were applied to the insulators. The power frequency voltage tests were carried out under both dry and wet condition and the impulse voltage tests under only dry condition. The acquired results were compared one another and discussed in electrical breakdown characteristic by analyzing the flashover progress pictures. As a result, the electrical strength of the broken toughened glass insulators was acquired and the processes of the surface breakdown on the toughened glass insulators were confirmed.

Prepartum Feeding of Cationic or Anionic Diets to Holstein Cows Given 30 or 60 Day Dry Periods: Comparison of Dry Matter Intake, Physiological Measures and Milk Production

  • Gulay, M.S.;Hayen, M.J.;Bachman, K.C.;Head, H.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.1
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    • pp.83-89
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    • 2008
  • Eighty-four Holstein cows were used to evaluate effects of feeding two diets that differed in dietary cation-anion difference (cationic; +28 or anionic; -138 mEq/kg DM) on prepartum and postpartum dry matter intake (DMI), body weight (BW), body condition score (BCS), serum Ca concentrations and on subsequent milk production and composition. Treatments were in a $2{\times}3{\times}2$ factorial arrangement that included prepartum diet, dry period length (30 d dry, 30 d dry+estradiol cypionate (ECP), and 60 d dry), and prepartum and postpartum bST ($POSILAC^{(R)}$ 10.2 mg/d). No interaction of prepartum diet with dry period length or bST supplementation was detected for any measure evaluated either prepartum or postpartum. No significant effects of prepartum diet on prepartum DMI, BW or BCS were observed. Mean DMI during the first 28 d postpartum were similar for cows fed the cationic or anionic diets prepartum (25.5 vs. 26.1 kg/d). During postpartum wk 1 to 14, no differences in mean BW or BCS were detected due to prepartum diet fed but decreases for both groups were observed during the first 6 wk postpartum. No differences due to prepartum diet were observed for mean milk or 3.5% FCM yields or for milk composition during the first 10 wk of lactation. Similarly, mean milk yield of cows during the first 21 wk did not differ significantly due to prepartum diet fed (38.5 vs. 38.6 kg/d). Overall, cows fed the prepartum cationic or anionic diets had similar mean postpartum serum concentrations of Ca (9.34 vs. 9.35 mg/dl). Subsequent milk production, milk composition and concentrations of Ca did not differ. Importantly, the two prepartum diets were equally satisfactory in minimizing incidence of milk fever and in supporting initiation of lactation, irrespective of dry period length and supplemental ECP and bST.

Improving Productive and Reproductive Performance of Holstein Dairy Cows through Dry Period Management

  • Safa, S.;Soleimani, A.;Heravi Moussavi, A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.5
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    • pp.630-637
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    • 2013
  • To determine the effects of dry period (DP) length on milk yield, milk composition, some blood metabolites, complete blood count (CBC), body weight and score and follicular status, twenty five primiparous and multiparous Holstein cows were assigned to a completely randomized design with DP-60 (n = 13) and DP-20 (n = 12) dry period lengths. Cows in the DP-60 produced more milk, protein, SNF, serum non-esterified fatty acids (NEFA) and beta hydroxyl butyrate acid (BHBA) compared with cows in DP-20 ($p{\leq}0.05$). Serum glucose, blood urea nitrogen (BUN), urea, and glutamic oxaloacetic transaminase (GOT) were all similar among the treatments. Body Condition Score (BCS), body weight (BW), complete blood count (CBC) and health problems were similar between the treatments. Diameter of the first dominant follicle and diameter of the dominant follicle on d 14 were different among the treatments. Thus, results of this study showed that reducing the dry period length to DP-20 had a negative effect on milk production, milk composition and reproductive performance in Holstein dairy cows.

EFFECT OF UREA ON WET RICE STRAW FOR PRESERVING ITS KEEPING QUALITY AND NUTRITIVE VALUE IN CATTLE DIETS

  • Chowdhury, S.A.;Huque, K.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.9 no.2
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    • pp.181-187
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    • 1996
  • About 8 million tons of straw (dry matter) become rotten during the monsoon(June to August) season in Bangladesh. The possibility of preserving straw with urea, under wet condition during dry period (December to May) and its utilization by cattle has been studied. Five tons of fresh and wet(600g DM/kg material) rice straw were preserved for six months, with 5% urea(W/W) in either dome or rectangular shaped heap without any polythene cover. The preservation quality, acceptability and nutritive value of preserved straw were then comparted with that of dry straw in growing cattle. In both types of heaps, straw was excellently preserved having strong ammonia smell,dark brown in colour with no fungal infestation. Urea preservation of straw increased its CP and ADF content. Preserved straw was readily accepted by the animals and they were healthy throughout the experimental period. Compared to dry straw, urea preserved straw had nonsignificantly higher rumen degradability, straw intgake and growth rate. Similarly, digestibilities of DM(p<0.01), OM(p<0.01) & ADF(p<0.01) were significantly higher in the preserved than the dry straw. It was concluded that wet straw with relatively lower moisture(400 to 500 g/kg straw) content can be readily preserved by using urea without being covered with polythene. Whether the same phenomenon occurs in the preservation of fresh and weet rice straw with relatively higher moisture(600 to 700 g/kg straw) content is yet to be determined.

Germination Percentages of Different Types of Sweet Corn in Relation to Harvesting Dates

  • Lee, Myoung-Hoon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.45 no.1
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    • pp.55-58
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    • 2000
  • Germination of sweet and super sweet corn is lower than normal corn due to the higher sugar and lower starch contents of kernels. Sweet corn seeds are easily deteriorated in the field under the unfavorable condition, therefore it is important to identify the optimal harvesting time for seed production. This trial was conducted to investigate the responses of germination percentage of shrunken-2(sh2), brittle(bt), sugary(su), and sugary enhancer(se) hybrids in relation to harvesting dates. Eight hybrids of four different gene sweet corns were harvested at 15, 20, 25, 30, 35, 40, 45, and 50 days after silking(DAS). Germination test was performed using paper towel method. Mean germination percentages across eight hybrids showed the highest value at 45 DAS. There were significant differences among genes and within gene for germination. Shrunken-2 hybrid Mecca was higher than su hybrids for germination, indicating that sh2 would not be poorer than su Late harvesting beyond the optimal harvesting date might not be desirable because of more lodging and ear rots. Theoretical optimal harvesting date estimated from the regression equation was 40.9 DAS, however, practical date for harvesting would be a few days later than the estimated date if seedling vigor might be considered. Kernel dry weight per ear showed similar response to germination. Regression equation showed the highest kernel dry weight at 40.7 DAS. Significant correlations between kernel dry weight and germination were observed, impling that kernel dry matter accumulation would be an important factor for germination.

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Histochemical Study on the Serous Gland of Frog(Rana nigromaculata) Skin under Dry Conditions (건조상태가 개구리(Rana nigromaculata) 피부 장액선에 미치는 영향에 대한 조직화학적 연구)

  • Park, Joong-Suk
    • The Korean Journal of Zoology
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    • v.18 no.3
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    • pp.107-114
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    • 1975
  • This study was performed in order to know the histochemical changes of mucosubstances in granular secretions of the serous gland under normal and dry conditions. The frogs were collected near Jinju and the experimental groups were retained under dry conditions for 24, 48, 72 and 96 hours to make a comparison with normal group. The results obtained were as follows: 1. The secreting granules in serous gland of the frog skin contained neutral and weakly acidic mucosubstances. 2. the secreting granules in serous gland of the frog skin were significantly decreased under dry conditions, as is evident from the histochemical properties. The neutral mucosubstances were decreased more than acidic mucosubstances. 3. Histochemical compositions of the mucosubstances of secreting granules in the lumen of the serous gland were not changed according to dry condition.

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Improvement of Growth of Potato (Solanum tuberosum L. cv. Dejima) Plants at In Vitro and Ex Vitro and Energy Efficiency by Environmental Control with Growth Stage in Photoautotrophic Micropropagation System (광독립영양 기내 미세증식 시스템에서 생육단계별 환경조절을 통한 감자의 기내 및 기외 생육과 에너지 효율 향상)

  • Oh, Myung-Min;Lee, Hoon;Son, Jung-Eek
    • Journal of Bio-Environment Control
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    • v.18 no.1
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    • pp.23-28
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    • 2009
  • This study was conducted to evaluate the effect of optimized environment conditions with growth stage in photoautotrophic micropropagation on the growth of potato (Solanum tuberosum L. cv. Dejima) plantlets and energy efficiency. Optimum environment conditions at each stage were decided in our previous study. For the evaluation of optimized environment control, potato plantlets were cultured under four different conditions: photoautotrophic optimum conditions of photosynthetic photon flux density (PPFD) and $CO_2$ levels with growth stage (POG), photoautotrophic constant condition with average PPFD and $CO_2$ levels (PCA), photoauototrophic constant condition with maximum PPFD and $CO_2$ levels (PCM), and photomixotrophic conventional condition with 3% sucrose (PMC) as control. As a result, environment control with growth stage (POG) significantly promoted all the growth characteristics such as the number of nodes and unfolded leaves, shoot height, shoot diameter, and fresh and dry weights of potato grown in vitro. In addition, based on dry weight consumed electricity and $CO_2$ were the lowest in POG suggesting the highest energy efficiency among the treatments. After transferring potato plantlets to greenhouse, the plantlets under POG showed vigorous growth, which was pretty similar with those under PMC. The accumulations of dry matter in POG were 4.7 times in vitro and 3.8 times in greenhouse as much as those in the conventional control (PCM). Thus, we concluded that in vitro environment control with growth stage induced vigorous growth of potato plantlets both in vitro and in greenhouse with less energy consumption.

Morphological and Anatomical Response of Rice and Barnyardgrass to Herbicides under Various Cropping Patterns -II. Response to Bensulfuron (재배양식(栽培樣式)에 따른 수종(數種) 제초제(除草劑)에 대한 벼와 피의 해부형태적(解剖形態的) 반응차이(反應差異) - II. Bensulfuron 에 대한 반응차이(反應差異))

  • Chon, S.U.;Guh, J.O.;Kuk, Y.I.;Han, S.U.
    • Korean Journal of Weed Science
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    • v.16 no.3
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    • pp.230-236
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    • 1996
  • Pot experiment in greenhouse was conducted to determine the effect of growth and anatomical characteristics of bensulfuron on the seedlings of rice and barnyardgrass. Formulated bensulfuron was soil applied at 102g ai/ha to rice and barnyardgrass grown under various cropping patterns at 5 days after seeding or transplanting. At 10 days after application, plants were harvested to examine growth and anatomical changes of rice and barnyardgrass. Bensulfuron did not affect the growth and development of rites under dry seeded condition and trnsplanting condition while inhibited severely those of rice under water-seeded condition compared with untreated control. Under water-seeded condition, root growth of rice was much more severely inhibited by bensulfuron than shoot growth. The herbicide retarded the growth of barnyardgrass under dry-seeded condition and more severely inhibited than that under water-seeded condition. Microscopically, the anatomical change induced by bensulfuron occurred only in barnyardgrass under dry-seeded condition, and involved constriction of leaf primordia within leaf sheaths, rupture of mesophyll cell, and irregular cell arrangement. These anatomical alterations differed from and were not associated with the differential growth response.

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