• Korean journal of applied entomology
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• v.61 no.1
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• pp.165-172
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• 2022

Insects have evolved successfully by adapting to their environments through development and reproduction. Temperature-dependent models have been used to calculate the intrinsic optimal, optimal development, and optimal fecundity temperatures of insects and mites; for this study, we reviewed 112 works that focused on these parameters. The insects and mites investigated in this study include 14 Acari, 8 Coleoptera, 5 Diptera, 31 Hemiptera, 7 Hymenoptera, 18 Lepidoptera, 1 Orthoptera, 5 Psocoptera, and 5 Thysanoptera species. The results of this study showed that the interval distance between the intrinsic optimal and optimal fecundity temperatures was smaller than that between the intrinsic optimal and optimal development temperatures of the all insects and mites investigated except for those in the order Thysanoptera. We found that there is a close relationship between the intrinsic optimal and optimal fecundity temperatures.

• Korean Journal of Environment and Ecology
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• v.38 no.2
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• pp.143-147
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• 2024

This study aimed to determine the egg-hatching period of boreal digging frogs, Kaloula borealis, and investigate whether the incubation temperature affects the hatching period. In this study, the egg hatching was recorded based on the appearance of the tadpole. The results of this study showed that all the eggs hatched within 48 hours after spawning, with 28.1% (±10.8, n=52) hatching within 24 hours and 99.9% (±0.23, n=49) within 48 hours after spawning. The mean hatching rate of tadpoles showed significant differences depending on the difference in water temperature. The mean hatching rate between 15 and 24 hours after spawning was higher at a water temperature of 21.1 (±0.2) ℃ than at 24.1 (±0.2) ℃. The results suggest rapid hatching occurs at relatively low water temperatures because the spawning habits that spawn eggs in temporary ponds or puddles in the rainy season require rapid hatching before the puddles dry out. The results of this study are helpful for understanding the most suitable temperature conditions for the incubation of eggs of the endangered species, boreal digging frog.

• Publications of The Korean Astronomical Society
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• v.14 no.2
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• pp.123-128
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• 1999

The beam size and the antenna efficiency of TRAO 14m radio telescope were measured at 86.2, 98.0 and 115.2 GHz. The beam size was determined by deconvolving the azimuthal scanning data of the Venus. To test the accuracy of our deconvolution method, the beam size at 86.2 GHz was compared with that determined from the mapping data of SiO maser line and we found no difference between them. With above beam sizes, antenna efficiencies were calculated from the continuum measurements of Venus, Jupiter and Moon. The beam efficiencies at these frequencies are appeared to be 0.49, 0.45 and 0.41, respectively. On the other hand, we also suggest that an automatic focus setting can be adopted for TRAO radio telescope based on the gradual change of best focus with elevation.

• The Journal of the Acoustical Society of Korea
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• v.13 no.1E
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• pp.45-54
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• 1994

Characteristics of a piezoelectric material are evaluated to pick up the optimal crystal cut and propagation direction for a SAW device. For the piezoelectric single crystal $LiTaO_4$, such items are investigated as the Rayleigh wave velocity, the electromechanical coupling factor, the surface permittivity, the frequency-temperature coefficient, the air loading attenuation, the pure mode propagation, the beam steering and the misalignment sensitivity. Theoretical calculations reveal that Y-cut and Z-propagation is the optimal SAW propagation path. The results are confirmed through experiments. The method empolyed in this paper is applicable to other crystals, too, either single or poly crystals.

• Korean journal of applied entomology
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• v.26 no.2 s.71
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• pp.71-81
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• 1987

This study was conducted to study the effects of temperature on the oviposition, feeding and emergence of the azuki bean weevil(ABW) (Callesobruchus chinensis L.) in the stored beans. And ovipositional preference, hatching and emergence on the preference and non-preference hosts were also investigated. ABW has four generations a year and overwinters as larva stage in the bean grains. Optimum oviposition temperature of the ABW ranges from $25^{\circ}C\;to\;30^{\circ}C$. Oviposition preference in different hosts was in the order of azuki bean, mung bean, soy bean, kidney bean, black-soybean, pea. At $25^{\circ}C$, optimum development temperature emergence of period the ABW averaged 29 days on azuki bean, 31 days on mung bean, 49 days on soy bean, 46 days on black-soybean, 34 days on Pea. Percent hatch in different hosts was in the order of azuki bean, mung bean, soy bean, pea, black-soybean, kidney bean. But percent emergence was in the order of azuki bean, mung bean, pea, black-soybean, kidney bean. Especially, in azuki bean and mung bean, percentage of hatching and emergence was very high. And in soy bean and black-soybean, percentage of hatching was high but emergence was low. The kidney bean was hatching but not emergence at all. The longevity at the different temperatures appeared to be $4{\sim}5$ days at $35^{\circ}C,\;5{\sim}7$ days at $25^{\circ}C{\sim}30^{\circ}C$, $10{\sim}15$ days at $20^{\circ}C\;and\;19{\sim}24$ days at $15^{\circ}C$. Kidney bean of feeding non-preference host oviposited at Seed coat and Endosperm, but no larva developed. And cotyledon and embryo parts were not oviposited at all. The percentage of germination of egg laid bean grain and damaged bean grains was low. Especially, the percentage of germination of damaged bean grains was 0% on azuki bean, 5% on black-soy bean, 7% on Pea.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.555-561
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• 1999

The development of sycamore lace bug, Corythucha ciliata, had been studied at four constant temperature levels of 15, 20, 25, and $30^{\circ}C$. And characteristics of its oviposition were studied at field. Developmental periods of eggs were 39.1, 17.1, 9.8, and 8.0 days, those of nymphs were 58.5, 23.8, 14.5, and 10.8 days, hatchabilities of eggs were 42.0, 78.5, 83.3, and 78.7%, and survival rates of nymphs were 14.7. 60.5, 75.7, and 48.9% at different temperatures of 15, 20, 25, and $30^{\circ}C$. Lower development threshold temperature and the effective accumulative temperature above the threshold required to complete development from egg to nymph were $11.5^{\circ}C$ and 344.8 degree days, respectively. The optimum temperature was estimated to be $25^{\circ}C$ for developments of egg and nymph. The longevities of adults were 41.0 days and 37.0 days for female and male, respectively.

• Journal of Aquaculture
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• v.6 no.3
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• pp.147-157
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• 1993

The harpacticoid copepod, Tigriopus japonicus is one of the most important zooplankton as a live food for the production of marine fish fry. Thus, the salinity tolerance and the optimum culture environment of this copepod in terms of salinity, temperature and light were examined. The food values of 6 kinds of phytoplankters and 2 kinds of yeast were also investigated for mass culture of this copepod. The results are as follows: After 5 day culture in the experiment of salinity tolerance, the survival rates of the gravid female at $0\%\;and\;90%o\;were\;40\%\;and\;70\%$, respectively. However, at salinity ranging from $2\%o\;to\;80\%o$, high survival rates above $85\%$ were observed. It means T. japonicus is very euryhalinous species. Temperature was more important factor than salinity for the fecundity of T. japonicus. The optimum culture conditions of this species were $24^{\circ}C,\;24\%o$, and 3,000 lux with 24 L: 0D. Under these culture conditions, the average fecundity from a gravid female per spawning was 38 nauplii, and the interval time between spawnings were 2.05 days. Phaeodactylum tircornutum seemed to be the most suitable phytoplankton as a live food for T. japonicus, and the large chlorophyta, Tetraselmis suecica showed the lowest food value among 6 phytoplankters and 2 yeasts. The food value of w-yeast was better than that of baker's yeast, and it is similar to that of phytoplankton such as Amphora sp., Chlorella ellipsoidea and Nannochloris oculata. So, the w-yeast seems to be appropriate food source for mass culture of T. japonicus.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.777-784
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• 2017

Energy harvesting through a thermoelectric module normally makes use of the temperature gradient in the system's operational environment. Therefore, it is difficult to obtain the desired output power when the system is subjected to an environment in which a low temperature gradient is generated across the module, because the power generation efficiency of the thermoelectric device is not optimized. The utilization of solar energy, which is a form of renewable energy abundant in nature, has mostly been limited to photovoltaic solar cells and solar thermal energy generation. However, photovoltaic power generation is capable of utilizing only a narrow wavelength band from the sunlight and, thus, the power generation efficiency might be lowered by light scattering. In the case of solar thermal energy generation, the system usually requires large-scale facilities. In this study, a simple and small size thermoelectric power generation system with a solar concentrator was designed to create a large temperature gradient for enhanced performance. A solar tracking system was used to concentrate the solar thermal energy during the experiments and a liquid circulating chiller was installed to maintain a large temperature gradient in order to avoid heat transfer to the bottom of the thermoelectric module. Then, the setup was tested through a series of experiments and the performance of the system was analyzed for the purpose of evaluating its feasibility and validity.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.148-148
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• 2000

지금까지 반도체 표면에 대한 연구는 주로 (1000, (111) 표면 등 낮은 밀러 지표를 가진 표면에 대해 이루어져 왔다. 이에 반해 밀러 지표가 높은 Si 면은 불안정하고, 가열하면 다른 표면, 즉 지표가 낮은 면으로 재배열하는 경향이 있는 것으로 알려져 있는데 아직 이들 높은 밀러 지표를 가진 표면에 대한 연구는 미미한 상태이다. 그러나, Si(113)면은 밀러 지표가 높으면서도 안정하기 때문에 Si(113)의 구조를 정확하게 알 수 있다면 밀러 지표가 낮은 Si 표면이 안정한 이유를 이해할 수 있을 것이다. 따라서 본 연구에서는 TOF-CAICISS 장치(Time of Flight - CoAxial Impact Collision Ion Scattering Spectroscopy) 장비와 RHEED(Reflection High Energy Electron Diffrction)를 이용하여 Si(113) 표면의 구조와 Si(113) 표면의 온도에 따른 구조 변화를 관찰하였다. TOF-CAICISS 실험결과를 보면 (3$\times$2)에서 (3$\times$1)으로 상변환하면서 Si(113) 표면에 오각형을 이루는 dimer 원자들과 adatom 원자들간의 높이차가 작아짐을 알 수 있다. RHEED 실험결과와 전산 모사 결과로부터 상온에서 Si(113)(3$\times$2) 구조를 가지다가 45$0^{\circ}C$~50$0^{\circ}C$에서 Si(113) (3$\times$1) 구조로 상변환한다는 것을 알 수 있다. 그러나, 아직 상전이 메카니즘은 명확하게 밝혀지지 않았다. 실험결과를 전산 모사와 비교함으로써 Si(113) 표면에 [33]방향으로 이온빔을 입사시켰을 경우 dabrowski 모델과 Ranke AI 모델이 적합하지 않다는 것을 알 수 있다./TEX>, shower head의 온도는 $65^{\circ}C$로 설정하였다. 증착된 Cu 박막은 SEM, XRD, AFM를 통해 제작된 박막의 특성을 비교.분석하였다. 초기 plasma 처리를 한 경우에는 그림 1에서와 같이 현저히 증가한 초기 구리 입자들이 관측되었으며, 이는 도상 표면에 활성화된 catalytic site의 증가에 기인한다고 보여진다. 이러한 특성은 Cu films의 성장률을 향상시키고, 또한 voids를 줄여 전기적 성질 및 surface morphology를 향상시키는 것으로 나타났다. 결과 필름의 잔류 응력과 biaxial elastic modulus는 필름의 두께가 감소함에 따라 감소하는 경향을 나타냈으며, 같은 두께의 필름인 경우, 식각 깊이에 따른 biaxial elastic modulus 의 변화를 통해 최적의 식각 깊이를 알 수 있었다.도의 값을 나타내었으며 X-선 회절 data로부터 분석한 박막의 변형은 증온도에 따라 7.2%에서 0.04%로 감소하였고 이 이경향은 유전손실은 감소경향과 일치하였다.는 현저하게 향상되었다. 그 원인은 SB power의 인가에 의해 활성화된 precursor 분자들이 큰 에너지를 가지고 기판에 유입되어 치밀한 박막이 형성되었기 때문으로 사료된다.을수 있었다.보았다.다.다양한 기능을 가진 신소재 제조에 있다. 또한 경제적인 측면에서도 고부가 가치의 제품 개발에 따른 새로운 수요 창출과 수익률 향상, 기존의 기능성 안료를 나노(nano)화하여 나노 입자를 제조, 기존의 기능성 안료에 대한 비용 절감 효과등을 유도 할 수 있다. 역시 기술적인 측면에서도 특수소재 개발에 있어 최적의 나노 입자 제어기술 개발 및 나노입자를 기능성 소재로 사용하여 새로운 제품의 제조와 고압 기상 분사기술의 최적화에 의한 기능성 나노 입자 제조 기술을 확립하고 2차 오염 발생원인 유기계 항균제를 무기계 항균제로 대체할 수 있다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.366-376
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• 1997

$CdGa_2Se_4$, epilayer of tetragonal type are grown on Si(100) substrate by hot wall epitaxy method. The source and substrate temperature is $580^{\circ}C$ and $420^{\circ}C$ respectively, and the thickness of the film is 3 $\mu \textrm{m}$. The crystallihe structure of epilayers were investigated by double crystal X-ray diffraction(DCXD). Hall effect on this sample was measured by the method of van der Pauw and studied on carrier density and mobility depending on temperature. From Hall data, the mobility was likely to be decreased by pizoelectric scattering in the temperature range 30 K to 200 K and by polar optical scattering in the temperature range 200 K to 293 K. In order to explore of photocurrent to darkcurrent (pc/dc), maximum allowable power dissipation (MAPD), spectral response and response time. The results indicated that for the samples annealed in Se vapor the photoconductive characteristics are best. Then we obtained the sensitivity of 0.98, the value of pc/dc of $9.62{\times}10^6$, the MAPD of 321 ㎽ and the rise and decay time of 9 ㎳ and 9.5 ㎳, respectively.