• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.3
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• pp.263-275
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• 1986

Gulbi were processed by salting Yellow corvenia (Pseudosciaena manchurica) with in three ways: the dry salting method with bar salt, the dry salting method with purified salt or with the abdominal brine injection method with purified salt. The half of the sample was dried by the control system of temperature and humidity; the other part was dried by the natural condition. The moisture content of fresh Yellow corvenia muscle and eggs were 76.8%, and 68.2% while those of dried samples decreased to 57.7% and 45.3%, respectively. The total nitrogen content of fresh muscle and eggs were 11.0g% and 7.6g%, respectively (dry weight basis), which decreased slightly during salting and showed no significant changes during drying prosess. The protein nitrogen content of fresh muscle and eggs were 10.2g% and 7.5g%, which decreased during Gulbi processing. On the other hand, the nonprotein nitrogen content of both muscle and eggs increased. The content of free amino acids of fresh muscle and eggs were 508.8mg/100g and 1,110.6mg/100g, which increased to between 5.3 and 2.7 times, respectively after 25 days of drying. The composition patterns of free amino acids in muscle and eggs were similar to each other. The four amino acids - Ala, Glu, Lys and Leu - were most abundant in both fresh and dried samples. These amino acids are known as taste and flavour constituents.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.233-246
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• 2009

The partitioning of evapotranspiration (ET) into evaporation (E) and transpiration (T) is critical in understanding the water cycle and the couplings between the cycles of energy, water, and carbon. In forests, the total ET measured above the canopy consists of T from both overstory and understory vegetation, and E from soil and the intercepted precipitation. To quantify their relative contributions, we have measured ET from the floors of deciduous and coniferous forests in Gwangneung using eddy covariance technique from 1 June 2008 to 31 May 2009. Due to smaller eddies that contribute to turbulent transfer near the ground, we performed a spectrum analysis and found that the errors associated with sensor separation were <10%. The annual sum of the understory ET was 59 mm (16% of total ET) in the deciduous forest and 43 mm (~7%) in the coniferous forest. Overall, the understory ET was not negligible except during the summer season when the plant area index was near its maximum. In both forest canopies, the decoupling factor ($\Omega$) was about ~0.15, indicating that the understory ET was controlled mainly by vapor pressure deficit and soil moisture content. The differences in the understory ET between the two forest canopies were due to different environmental conditions within the canopies, particularly the contrasting air humidity and soil water content. The non-negligible understory ET in the Gwangneung forests suggests that the dual source or multi-level models are required for the interpretation and modeling of surface exchange of mass and energy in these forests.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.409-414
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• 2010

The first drainage time in a day was controlled for precise irrigation management with low consumption of nutrient solution in tomato perlite bag culture system by measuring water level of drained water in drainage catchment part. This method automatically adjusted the irrigation time under any condition of light, temperature and humidity, resulting in stable water content in substrates. However, it was difficult to keep the time consistent as they were set. It drained with the deviation of 20 min in the treatment in which the first drainage time was set at 10:00 and 50 min in the treatment set at 10:30. The first drainage time was not constant, but the drain occurred stably before noon in the treatment of which irrigation frequency was longer than 30 min. The drainage ratio was better balanced in all the treatments using drainage level sensors than the treatment using time clock for irrigation control. High water and fertilizer efficiencies were obtained. Although the growth, total yield and sugar content were not significantly different between the treatments, fruit weight was higher in the treatments using drainage level sensors than that using timer.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.194-199
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• 2005

The principle of vortex cyclone was applied to enhance the treatment efficiency of waste air streams containing particulate matters, phenol, and others. Adsorption, condensation, and/or coagulation could be induced at low temperature zone formed by Joule-Thomson expansion as the pressurized air and pulverized activated carbon were introduced at the tangential direction into the cyclone system applied with the coaxial funnel tube of vortex cyclone. Easily condensible vapors were adsorbed and/or condensed forcibly on coagulated or condensed materials which were formed as cores for coagulation or condensation by themselves or on pulverized activated carbons. These types of coagulation or condensation rates were rapidly promoted by increase in their diameter. The maximum removal efficiency obtained from this experiment for the removal of carbon dioxide and phenol was about 87.3 and 93.8 percent, respectively. Phenol removal efficiency was increased with the relative humidities and enhanced by pulverized activated carbon added. The Joule-Thomson coefficients were increased with the pressure of air injected in the range of the relative humidities between 10% and 50%. It is believed that the moisture, particulate matters, and the pressure of the process air introduced could control the removal efficiency of VOCs.

• Korean journal of food and cookery science
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• v.2 no.2
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• pp.1-7
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• 1986

Gulbi were made by salting Yellow corvenia (Pseudosciaena manchurica) with the in three ways: the dry salting method with bay salt, the dry salting method with purified salt or with the abdominal brine injection method with purifie salt. The half of the sample was dried by the control system of temperature and humidity: the other part was dried by the natural condition. In fresh muscle, the content of IMP, hypoxanthine, inosine and AMP were $13.40,\;9.28,\;3.01{\mu}mole/g$ and trace amount, dry basis, respectively. In fresh egg, the content of AMP, hypoxanthine, inosine and IMP were 13.98, 6.56, 1.98 and $1.93{\mu}mole/g$, dry basis, respectively. During the drying process of Yellow corvenia, the content of hypoxanthine increased remarkably, while the content of AMP, IMP and inosine decreased ana remained as trace amount. It can be suggested that the characteristic flavor of Gulbi is not attributed to the nucleotides and their related compounds but rather to free amino acids.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.331-336
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• 2011

Capacitance soil moisture sensor is extensively used by soil research and irrigation management with its convenience and accuracy. This experiment was conducted to evaluate the acceptability of capacitance soil moisture sensor, named EnviroSCAN made by Sentek Ltd., in Jeju Island where volcanic ash soils are widely distributed, and to calibrate it to various soils with different amount of soil organic matter. For sensor calibration equation of volcanic ash soils, a logarithm function is better than a typical power function of non-volcanic ash soils. So there are possibilities of under evaluated in soil water contents in very wet and very dry conditions by using typical power function with volcanic ash soil areas. We suggested practical coefficients of typical calibration equation for using capacitance sensor in volcanic ash soils, also suggested equations for estimation of them with soil organic matter contents. The measurement of soil water content with a capacitance sensor can be affected by some soil characteristics such as porosity, soil organic matter content, EC, etc. So those factors should be controlled for improving the accuracy of measurement.

• Korean journal of applied entomology
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• v.62 no.3
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• pp.139-147
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• 2023

Leaf-spray in vitro bioassays appraise new aphicidal formulations for managing deleterious plant-feeding aphids. The formulation may utilize alternative and integrated strategies. However, leaf spraying even under controlled conditions may affect aphid reproduction and mortality. This study examines leaf spray applications for optimum and reproducible aphicidal results using tobacco leaves overlaid on cotton fabric or water agar surfaces. Infestation of the undersides of tobacco leaves with nymphs of green peach aphids was used in the assays. Spray distance and volume were optimized using water-sensitive paper to ascertain the best surface coverage. Overlays of the leaves on water agar caused less mortality and greater reproduction than the use of cotton fabric. The relative humidity of the insect-rearing chambers changed with the watering regime for the insect - rearing chambers with cotton fabric; 60% relative humidity was optimal. Relative humidity was not affected by the concentration of agar in the water agar chambers. Applications of the chemical aphicidal standard, Sulfoxaflor, under the optimized conditions exhibited similar times for lethality although the rate was faster with leaves on the cotton fabric than on water agar. These studies establish reproducible and sensitive techniques for assessing the lethality and effects on reproduction of potential aphicidal products.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.25-25
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• 2020

산초나무(Zanthoxylum schinifolium Siebold & Zucc.)는 운향과(Rutaceae)에 속하는 낙엽활엽관목으로 주로 열매, 잎, 줄기는 식·약용으로 이용한다. 최근 산초나무 부위별 추출물에서 항산화활성, 항염증효과, 미백효과 등에 관한 연구가 이루어지면서 산초나무의 가치가 더욱 증가하고 있다. 본 연구는 산초나무의 효율적인 유·무성 증식법을 구명하기 위해 종자 처리에 따른 발아특성, 생장조절물질 처리에 따른 가지삽목과 뿌리삽목의 발근특성을 조사하였다. 산초나무 종자는 3개월간 저온습사저장(종자:모래=1:1, -4℃)을 실시할 경우 약 64.0%가 발아하였다. 습사저장된 종자를 파종 직전에 GA3를 이용하여 0, 500, 1,000 및 2,000ppm 농도에서 처리한 결과 각 처리구별 발아율은 유의한 차이를 나타내지 않았다(F=1.556, p=0.260). 다만, 500ppm 농도에서 72.0%가 발아하여 가장 높은 발아율을 보였으며 1,000ppm 이상 처리구에서는 발아율이 다소 감소하는 경향을 나타냈다. 무성증식 방법은 2월 중순에 산초나무 가지삽수와 뿌리삽수를 채취한 후 IBA와 NAA를 각각 0, 500, 1,000 및 2,000ppm 농도로 처리하였다. 가지삽목을 실시한 대부분의 삽수에서 신초가 발생했으나, 발근율은 1.3~6.3%로 현저히 낮았다. 반면, 뿌리삽목은 3개월 후 부정아 발생율이 처리에 따라 58.3~83.3%로 조사되었으며, 발근율은 0~66.7%를 나타나 처리구별 발근율에 유의한 차이가 있었다(F=3.744, p=0.020). IBA 처리가 근삽수의 발근에는 효과적이었으며, 특히 IBA 2,000ppm 처리에서 66.7%의 발근율을 보여 가장 효과적임을 알 수 있었다. 결론적으로, 산초나무의 효율적인 유성증식을 위해서는 종자를 3개월간 저온습사저장하는 것이 효과적이며, 무성증식 방법으로는 가지삽목보다 뿌리삽목을 이용하는 것이 더 효과적인 것으로 판단된다.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.299-304
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• 2012

In this work, we experimented with the two-fluid fogging system that eco-friendly prevents whiteflies in greenhouses in order to find the optimal concentration of oleic acid supplied through the system and to evaluate the control value of three consecutive treatments. The first experiment, which was to find the optimal concentration of oleic acid, used "Dotaerang Gold" tomatoes grown in stand-alone plastic greenhouse at Buyeo Tomato Experiment Station. We tested three levels of concentration of oleic acid, which were 0, 2000, and 4000 ppm. The second experiment, which was to evaluate the control value of three consecutive treatments of oleic acid, used "Rokusanmaru" tomatoes grown in Venlo type glasshouse at Gyeonggi-Do Agricultural Research & Extension Services. In this experiment, oleic acid of 2000 ppm was applied three times with two days intervals. The number of whiteflies was counted 2 two days after the last application of oleic acid. Even when oleic acid was not being applied, the two-fluid fogging system was run from 9:00 am to 5:00 pm whenever the temperature is higher than $25^{\circ}C$ or the humidity is lower than 75%. In the first experiment, the control value was 81.6% with 2000 ppm of oleic acid and 93.6% with 4000 ppm. It means that the higher the concentration is, the greater the control value. In the second experiment, 2000 ppm treatment resulted in 85.8% of the control value, which is higher than the required standard for insecticides. Hence, spraying oleic acid with the concentration of 2000 ppm three times with two days intervals turned out to be a very effective in the eco-friendly prevention of whitefly.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.220-227
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• 2012

This study was conducted to analyze the seeding quality of paprika and the growth and early yield after transplanting of paprika nursed under artificial light and natural light. In this study, blue LED, red LED, and white fluorescent lamps (FL) were used as artificial lighting sources. Photoperiod, average photosynthetic photon flux, air temperature, and relative humidity in a closed transplants production system (CTPS) were maintained at 16/8 h, $204{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, 26/$20^{\circ}C$, and 70%, respectively. Leaf length, leaf width, leaf area, top fresh weight and dry weight of paprika seedlings, and chlorophyll content in paprika leaves nursed under LED and fluorescent lamps for 21 days after experiment were significantly affected by light treatments. As compared with the control (white FL), leaf area of paprika grown under blue LED, red LED, and natural light was decreased by 63%, 63%, and 28%, respectively. Top dry weight of paprika grown under blue LED, red LED, and natural light was 64%, 50%, and 22%, respectively, compared with the control. Number of leaves on 18 days after transplanting showed with red LED, blue LED, and natural light by 86%, 84%, and 48%, respectively, compared with the control. On 114 days after transplanting, paprika nursed under blue LED and red LED had relatively short plant height. This result might be caused that the elongation of its internodes was suppressed by the illumination of sole blue or red light. Average number of fruits per plant harvested during 4 weeks after first harvest was 3.5 with red LED, 3.3 with blue LED, 1.0 with natural light, and 2.2 with control, respectively. Early yield of paprika nursed under red LED, blue LED, natural light, and control were 453 g/plant, 403 g/plant, 101 g/plant, and 273 g/plant, respectively. Larger fruit of 136 g was harvested with red LED treatment. Even though the early yield of paprika was greatly increased with artificial lighting, but total yield was almost similar as the harvest period after transplanting in greenhouses was lengthened. From the above results, we could understand that paprika nursed under white FL, blue LED, and red LED showed good growth after transplanting and was early harvested by a week as compared to the natural light. Therefore, the white FL, blue LED, and red LED as the artificial lighting sources in CTPS could be strategically used to enhance the seedling quality, to shorten the harvest time, and to increase the yield of paprika.