• 제목/요약/키워드: adaptability to temperature

검색결과 128건 처리시간 0.025초

리본 형태의 근관에서 열연화주입법의 근관벽에 대한 적합도에 관한 연구 (A COMPARISON OF THERMOPLASTICIZED INJECIABLE GUTTA-PERCHA TECHNIQUES IN RIBBON-SHAPED CANALS : ADAPTATION TO CANAL WALLS)

  • 황현숙;조경모;김진우
    • Restorative Dentistry and Endodontics
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    • 제27권4호
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    • pp.411-420
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    • 2002
  • The aim of this study is to compare the adaptability of thermoplasticized injectable gutta-percha technique to the canal walls in ribbon-shaped canals. Thirty resin models simulated ribbon-shape canals were instrumented to #40 using .06 taper Profile systems. Three groups of each 10 resin models were obturated by the lateral condensation technique(LC) and the two thermoplasticized injectable gutta-percha technique; Ultrafil Endoset+Obtura II(EO) and Ultrafil Firmset(UF), respectively. After resin model were kept at room temperature for 4 days, they were resected horizontally with micro-tome at 1, 2, 3, 4 and 5mm levels from apex. At each levels. image of resected surface were taken using CCD camera under a stereomicroscope at $\times$40 magnification and stored. Ratio of the area of gutta-percha was obtained by calculating area of gutta-percha cone to the total area of canal using digitized image-ana-Iyzing program. The data were collected then analyzed statistically using One-way ANOVA. The results were as follows. 1 At 1mm levels, there was no statistically significant difference in the mean ratio of gutta-percha among the groups. 2. At 2mm level, EO showed the highest mean ratio of gutta-percha (p<0.05) and there was no significant difference between LC and UF. 3. At 3, 4, 5mm levels, EO and UF had significantly greater mean ratio of gutta-percha than LC(p<0.05) and there was no significant difference between EO and UF. In conclusion, the thermoplasticized injectable gutta-percha techniques demonstrated relatively favorable adaptability to canal walls than lateral condensation technique in ribbon-shaped canals except for 1mm level.

Insect Adaptations to Changing Environments - Temperature and Humidity

  • Singh, Tribhuwan;Bhat, Madan Mohan;Khan, Mohammad Ashraf
    • International Journal of Industrial Entomology and Biomaterials
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    • 제19권1호
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    • pp.155-164
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    • 2009
  • The most important factors in environment that influence the physiology of insects are temperature and humidity. Insects display a remarkable range of adaptations to changing environments and maintain their internal temperature (thermoregulation) and water content within tolerable limits, despite wide fluctuations in their surroundings. Adaptation is a complex and dynamic state that widely differs in species. Surviving under changing environment in insects depends on dispersal, habitat selection, habitat modification, relationship with ice and water, resistance to cold, diapause and developmental rate, sensitivity to environmental signals and syntheses of variety of cryoprotectant molecules. The mulberry silkworm (Bombyx mori) is very delicate and sensitive to environmental fluctuations and unable to survive naturally because of their domestication since ancient times. Thus, the adaptability to environmental conditions in the silkworm is quite different from those of wild insects. Temperature, humidity, air circulation, gases and photoperiod etc. shows a significant interaction in their effect on the physiology of silkworm depending upon the combination of factors and developmental stage affecting growth, development, productivity and quality of silk. An attempt has been made in this article to briefly discuss adaptation in insects with special emphasis on the role of environmental factors and their fluctuations and its significance in the physiology of mulberry silkworm, B. mori.

우리나라에 도입된 스트로브잣나무의 산지-시험지간 상호작용 (Interaction Between Provenance and Site of Eastern White Pine (Pinus strobus) Imported into Korea)

  • 최형순;유근옥;현정오;김인식;조도현
    • 한국농림기상학회지
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    • 제13권4호
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    • pp.185-191
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    • 2011
  • This study was conducted to investigate growth performance and provenance by site interaction in Pinus strobus (Eastern White Pine) provenance tests for selecting superior provenances in Korea. P. strobus was planted in 1972 at four test sites in Korea and the growth was analyzed at age 39. The growth of P. strobus was positively correlated with relative humidity and precipitation and negatively correlated with temperature of the test sites. The portion of interaction term of the total variation explained 2.5% in height and 24.6% in diameter of the total variation according to the regression analysis. The method of combined stability and performance index (CSPi) ranked the North Carolina provenance as the best provenance with good adaptability.

기후변화에 따른 벼 적정 등숙기간의 변동과 대책 (Climate Change Impacts on Optimum Ripening Periods of Rice Plant and Its Countermeasure in Rice Cultivation)

  • 윤성호;이정택
    • 한국농림기상학회지
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    • 제3권1호
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    • pp.55-70
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    • 2001
  • It was unusual crop weather for 1998 and 1999 compared with normal in Korea. The consecutive days of the optimum ripening period for rice plant that had daily mean temperature 21~23$^{\circ}C$ for 40 days after flowering, increased with long anomalies in 1998~99. The air temperature during ripening period was much higher than the optimum temperature and lower sunshine hour than norm in the local adaptability tests of newly developed rice lines during those years. In response of rice cultivation to warming and cloudy weather during crop season, the yield shall be decreased. Most scientists agree that the rate of heating is accelerating and temperature change could become increasingly disruptive. Weather patterns should also become more erratic. Agrometeorologists could be analyzed yearly variations of temperature, sunshine hour and rainfall pattern focused on transient agroclimate change for last a decade. Rice agronomists could be established taking advantage of real time agricultural meteorology information system for fertilization, irrigation, pest control and harvest. Also they could be analyzed the characteristics of flowering response of the recommended and newly bred rice cultivars for suitable cropping plan such as cultural patterns and sowing or transplanting date. Rice breeders should be deeply considered introducing the characteristics of basic vegetative type of flowering response like Togil rices as prospective rice cultivars corresponding to global warming because of the rices needed higher temperature at ripening stage than japonica rices, photoperiod-sensitive and thermo-sensitive ecotypes.

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무습수 평판인쇄의 온도 의존성에 관한 연구 (A Study on the Temperature Dependence of Waterless Lithography)

  • 신춘범;강상훈;이상남
    • 한국인쇄학회지
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    • 제19권1호
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    • pp.42-54
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    • 2001
  • The combination of a silicone surfaced plate and high viscosity ink produced a waterless printing system that worked well, but had limitation. The limitation was that this system was restricted to relatively short run lengths. In the waterless printing process, the press tended to heat up rapidly. Heat in turn, broke down the resins in the inks, causing them to become more fluid. When the ink is heated, the viscosity will drop, the ink will become too liquid and the plate will no longer be able to resist it. The ink will adhere to the non-print portions of the plate, and will print as a very fine mist or speckle pattern in the non-image area. On the other hand, when the ink gets too cold, viscosity will increase until ink transfer is impeded. This study carried otu to investigate the effect of temperature variations of the inks on the print quality in waterless lithography and to examine the adaptability of waterless lithography to conventional offset press without cooling system.

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이온교환을 이용한 음용수의 $NH_3-N$ 처리 (Treatment of $NH_3-N$ in Drinking Water Using Ion Exchange)

  • 채용곤
    • 환경위생공학
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    • 제23권1호
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    • pp.67-72
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    • 2008
  • Ion exchange performance to remove Ammonium in water was studied using commercially available strong acidic cationic exchange resin of $Na^+$ type in the batch and continuous column reactors. The performance was tested using the effluent concentration histories for continuous column or equilibrium concentrations for batch reactor as a function of time until resins were exhausted or reached ionic equilibrium between resin and solution. The results shoed that cationic exchange resin used in this study was more effective than activated carbon or zeolite for ammonium removal. Ammonium removal with the ion exchange resin temperature to be high qualitative recording minuteness but increases about seasonal change of temperature was judged with the public law where the adaptability is excellent. When the pH comes to be high at 11 degree, the ammonium was not effectively removed.

여름철 시설 토마토 재배 시 Carbon Dioxide 처리가 광합성, 엽록소 형광, 항산화 효소 발현에 미치는 영향 (The effect of Photosynthesis, Chlorophyll Fluorescence, and Anti-Oxidation Enzyme Activity on Carbon Dioxide Treatment in Summer Greenhouse Cultivation for Tomato (Solanum Lycopersicum))

  • 우영회;홍규현;오대근;이관호;김동억
    • 현장농수산연구지
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    • 제18권1호
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    • pp.71-78
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    • 2016
  • 여름철 토마토 시설 재배 시 CO2 시용에 의한 고온적응성 향상을 구명하고 그 가능성을 검토하고자 실시하였다. CO2 시용 농도별 엽록소 형광을 측정한 결과 Fm/Fo과 Fv/Fm은 1000ppm 처리가 타 처리에 비하여 높았으며, Fo은 낮았다. 이는 1000ppm의 CO2 처리는 다른 처리에 비하여 고온 적응성이 높았음을 보여 주고 있다. 동일한 기온 조건하(30℃, 40℃)에서 광합성률은 CO2 농도에 따라 증가하였으며, 고온상태인 40℃ 조건하에서도 1000ppm의 CO2 시용은 30℃ 조건보다 광합성률은 낮았으나 그 값은 약 18.5μmolm-2s-1이였다. 슈퍼 도태랑(모모타로), 미니 찰 두 품종 모두 CO2 농도가 높을수록 항산화 효소인 Superoxide Dismutase 와 Peroxidase의 활성은 높았다. 미니찰 품종에서 CO2 농도와 온도변화에 따른 엽록소 형광 Fo의 변화양상을 조사하여 고온한계 온도를 추정한 결과 500ppm은 41℃, 1000ppm은 43℃였다.

이중외피 건물의 개구부 및 난방설비 제어를 위한 인공지능망의 적용 (Application of Artificial Neural Network for Optimum Controls of Windows and Heating Systems of Double-Skinned Buildings)

  • 문진우;김상민;김수영
    • 설비공학논문집
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    • 제24권8호
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    • pp.627-635
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    • 2012
  • This study aims at developing an artificial neural network(ANN)-based predictive and adaptive temperature control method to control the openings at internal and external skins, and heating systems used in a building with double skin envelope. Based on the predicted indoor temperature, the control logic determined opening conditions of air inlets and outlets, and the operation of the heating systems. The optimization process of the initial ANN model was conducted to determine the optimal structure and learning methods followed by the performance tests by the comparison with the actual data measured from the existing double skin envelope. The analysis proved the prediction accuracy and the adaptability of the ANN model in terms of Root Mean Square and Mean Square Errors. The analysis results implied that the proposed ANN-based temperature control logic had potentials to be applied for the temperature control in the double skin envelope buildings.

기본유의 변화가 안료의 발색에 미치는 영향과 Computer D-base해석 (Effect of Variable Base Glaze on the Gradation of Colouring and Analysis of The Computer D-Base)

  • 임희진;최성철
    • 한국세라믹학회지
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    • 제36권4호
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    • pp.333-342
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    • 1999
  • This research was performed to investigate how the basic glaze change affected colour development at high temperature with a stable colorant (spinel structure CoAl2O4 pigment) The compounded pigment which is widely used for porcelain was also tested for the basic glazes adaptability. The data from the test were recorded in a computer data-base program. Therefore could be easily used in the study related with a pottery field. CoO : Al2O3 system spinel pigment of barium glaze lime glaze zinc glaze lead glaze and talc glaze were chosen for this study. The colors of Cobalt blue bright blue, blue purple were seen at the wave lengths of 455-480nm at the firing temperature of 1250$^{\circ}C$. Stable color were obtained from lime glaze bar-ium glaze zinc glaze. All the information in the database were used to examine all the possible result of the test in the study of porcelain. When the test results database were examined in all temperature ranges the lack of adhesion with the pigment occurred at the temperature of 1150$^{\circ}C$. The lack of adhesion is seen due to vaporization of the lead glaze.

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Effect of Simulated Heat Stress on Digestibility, Methane Emission and Metabolic Adaptability in Crossbred Cattle

  • Yadav, Brijesh;Singh, Gyanendra;Wankar, Alok;Dutta, N.;Chaturvedi, V.B.;Verma, Med Ram
    • Asian-Australasian Journal of Animal Sciences
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    • 제29권11호
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    • pp.1585-1592
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    • 2016
  • The present experiment was conducted to evaluate the effect of simulated heat stress on digestibility and methane ($CH_4$) emission. Four non-lactating crossbred cattle were exposed to $25^{\circ}C$, $30^{\circ}C$, $35^{\circ}C$, and $40^{\circ}C$ temperature with a relative humidity of 40% to 50% in a climatic chamber from 10:00 hours to 15:00 hours every day for 27 days. The physiological responses were recorded at 15:00 hours every day. The blood samples were collected at 15:00 hours on 1st, 6th, 11th, 16th, and 21st days and serum was collected for biochemical analysis. After 21 days, fecal and feed samples were collected continuously for six days for the estimation of digestibility. In the last 48 hours gas samples were collected continuously to estimate $CH_4$ emission. Heat stress in experimental animals at $35^{\circ}C$ and $40^{\circ}C$ was evident from an alteration (p<0.05) in rectal temperature, respiratory rate, pulse rate, water intake and serum thyroxin levels. The serum lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase activity and protein, urea, creatinine and triglyceride concentration changed (p<0.05), and body weight of the animals decreased (p<0.05) after temperature exposure at $40^{\circ}C$. The dry matter intake (DMI) was lower (p<0.05) at $40^{\circ}C$ exposure. The dry matter and neutral detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ compared to $25^{\circ}C$ and $30^{\circ}C$ exposure whereas, organic matter (OM) and acid detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ than $40^{\circ}C$ thermal exposure. The $CH_4$ emission/kg DMI and organic matter intake (OMI) declined (p<0.05) with increase in exposure temperature and reached its lowest levels at $40^{\circ}C$. It can be concluded from the present study that the digestibility and $CH_4$ emission were affected by intensity of heat stress. Further studies are necessary with respect to ruminal microbial changes to justify the variation in the digestibility and $CH_4$ emission during differential heat stress.