• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.173-177
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• 2015

This experiment was conducted to determined the optimum planting density for the production of high quality bitter gourd (Momordica charantia L.) adapted in spring cultivation with the unheated greenhouse condition. 'Erave' variety was planted at three different planting densities (235, 305, $380plants{\cdot}10a^{-1}$) on March 26. The training method was six lateral vines with pinching the main one. The light intensity was lower in the higher planting density than the lower one. Net photosynthetic rates of the bitter gourd leaves in the higher density were significantly lower (41 to 71%) than the lower one. There was no difference in the fruit characteristics among treatments. But the root weight was heavier in the lower planting density ($235plants{\cdot}10a^{-1}$) as 113.1g than 96.0g of the higher planting density ($380plants{\cdot}10a^{-1}$). The number of the harvested fruit also higher in the lower planting density ($235plants{\cdot}10a^{-1}$) with 60.7 than 39.9 of the higher planting density ($380plants{\cdot}10a^{-1}$). The average fruit weight was the highest in the plot of $305plants{\cdot}10a^{-1}$ as 338.7g and lowest in the lower planting density ($235plants{\cdot}10a^{-1}$) as 285.2g. The total yield of $305plants{\cdot}10a^{-1}$ density was $5,359kg{\cdot}10a^{-1}$, which was higher than $4,068kg{\cdot}10a^{-1}$ of the lower planting density ($235plants{\cdot}10a^{-1}$). Marketable yield was increased by 24% in the planting density of $305plants{\cdot}10a^{-1}$($4,767kg{\cdot}10a^{-1}$) as compared to the lower density in $235plants{\cdot}10a^{-1}$($3,629kg{\cdot}10a^{-1}$) and increased by 13% in the planting density as $380plants{\cdot}10a^{-1}$($4,137kg{\cdot}10a^{-1}$). Therefore, the planting density of bitter gourd was desirable in $305plants{\cdot}10a^{-1}$ density for the higher yield and quality in the protected cultivation.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.161-167
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• 2011

The soil moisture has an important effect on growth and development of highbush blueberry (HB), mainly because the root system, devoid of root hairs, is superficial. Moreover, the texture and organic matter content of Korean soil is different from the main producing counties, such as USA and Canada. To facilitate the growth and development of HB and long-term maintenance of productivity, the research related to soil moisture condition in Korea should be the priority. This study was performed to investigate the growth properties of the HB in various soil moisture conditions in order to determine the irrigation trigger point and optimum soil water potential. The texture of soil used in this experiment was loam. For the experiments, the soil was mixed with peatmoss at a rates 30% (v/v). Irrigation was scheduled at -3, -4, -5, -8, -15 and -22 kPa soil water potential then investigated leaf macronutrient, bush growth, and fruit properties. The leaf K content of HB showed the same trend in the soil water potential, but Leaf P and Mg content was highest in -5 and -22 kPa, respectively. The productivity and growth amount of HB showed the peak at the range of -4~-8 kPa as normal distribution pattern, and greatly decreased at above -15 kPa. Total dry weight and Cane diameter were highest at -4 kPa, plant width, fruit weight and yield were highest at -5 kPa, and plant height, cane number and shoot tension were highest at -8 kPa. Soluble solids content showed same trend in the soil water potential, but titratable acidity, anthocyanins and total polyphenols were not significantly different. Therefore, the optimal soil water potential for the development and a maximum production of HB were a range of -4~-8 kPa, and the recommended ideal irrigation trigger point was within -15 kPa.

• Journal of the Korean Geotechnical Society
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• v.30 no.6
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• pp.23-39
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• 2014

An artificial rainwater reservoir installed in urban areas for recycling rainwater is an eco-friendly facility for reducing storm water effluence. However, in order to recycle the rainwater directly, the artificial rainwater reservoir requires an auxiliary system that can remove non-point source pollutants included in the initial rainfall of urban area. Therefore, the conventional soil filtration technology is adopted to capture non-point source pollutants in an economical and efficient way in the purification system of artificial rainwater reservoirs. In order to satisfy such a demand, clogging characteristics of the sand filter layers with different grain-size distributions were studied with real non-point source pollutants. For this, a series of lab-scale chamber tests were conducted to make a prediction model for removal of non-point source pollutants, based on the clogging theory. The laboratory chamber experiments were carried out by permeating two types of artificially contaminated water through five different types of sand filter layers with different grain-size distributions. The two artificial contaminated waters were made by fine marine-clay particles and real non-point source pollutants collected from motorcar roads of Seoul, Korea. In the laboratory chamber experiments, the concentrations of the artificial contaminated water were measured in terms of TSS (Total Suspended Solids) and COD (Chemical Oxygen Demand) and compared with each other to evaluate the performance of sand filter layers. In addition, the accumulated weight of pollutant particles clogged in the sand filter layers was estimated. This paper suggests a prediction model for removal of non-point source pollutants with theoretical consideration of the physical characteristics such as the grain-size distribution and composition, and change in the hydraulic conductivity and porosity of sand filter layers. The lumped parameter ${\theta}$ related with the clogging property was estimated by comparing the accumulated weight of pollutant particles obtained from the laboratory chamber experiments and calculated from the prediction model based on the clogging theory. It is found that the lumped parameter ${\theta}$ has a significant influence on the amount of the pollutant particles clogged in the pores of sand filter layers. In conclusion, according to the clogging prediction model, a double-sand-filter layer consisting of two separate layers: the upper sand-filter layer with the effective particle size of 1.49 mm and the lower sand-filter layer with the effective particle size of 0.93 mm, is proposed as the optimum system for removing non-point source pollutants in the field-sized artificial rainwater reservoir.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.233-238
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• 2012

We prepared sponge cakes consisting of 1.5%, 3%, 4.5%, or 6% Omija powder. The specific gravity and viscosity of sponge cake batter were measured. Also, the moisture content, color, volume index, weight and texture of the sponge cake were determined. Consumer preference tests of the sponge cakes were also conducted. The viscosity of cake batter tended to decrease as the ratio of Omija powder increased. The specific gravity of the control batter was 0.41, and there was no significant difference between the control and the cakes baked with 1.5%, 3%, 4.5%, and 6% Omija powder. The moisture content and weight of the cakes were not significantly different between the control and those made with Omija powder. Hunter 'L,', 'a,' and 'b' values of the crust decreased significantly as the amount of Omija powder in the cake increased. Hunter 'L' and 'b' values of the crumbs were low in the cakes with Omija powder, while 'a' values were high. Hardness and fracturability did not show any differences between the cakes. Adhesiveness and resilience of the control were high. The control sample showed the highest sensory score in overall preference. However, cakes made with 1.5% Omija powder obtained the highest values in color, softness, and flavor scores. Omija powder flavor and astringency scores increased as the amount of Omija powder increased, and sweetness did not show any differences among cakes. Intensity scores of egg flavors significantly decreased as the amount of Omija powder increased. Sensory scores of off-flavor significantly increased as the amount of Omija powder increased. Based on the results, 1.5~3% should be recommended as the optimum level of Omija powder to be added for the preparation of sponge cake.

• Journal of Gastric Cancer
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• v.7 no.4
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• pp.219-227
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• 2007

Purpose: Many reconstruction procedures have been developed in order to resolve patient complaints after a total gastrectomy. However, until now, there has been no general agreement with regard to the ideal reconstruction to perform after a total gastrectomy. Moreover, there have been few reports of the long-term effects of different reconstruction procedures. In this study, we compared the long-term nutritional status and quality of life for patients that received either a Roux-en-Y esophagojejunostomy (R-Y), jejunal interposition (JI), jejunal pouch interposition (JPI), or double tract reconstruction (DT), to determine the optimum reconstruction procedure after a total gastrectomy. Materials and Methods: The study consisted of 41 patients younger than 80 years who had undergone a total gastrectomy with curative resection and who had no evidence of recurrence at our hospital between August 2000 and January 2004. The patients were classified into the following four groups, according to the type of reconstruction; simple Roux-en-Y (R-Y group, n=15), jejunal interposition (JI; group, n=8), j Jejunal pouch interposition (JPI group, n=8), double tract interposition (DT group, n=10). The nutritional status was assessed by measuring body weight, serum albumin level, serum hemoglobin level, and the level of serum total protein, and the PNI (Prognostic nutritional index). Quality of life was assessed by GSRS. In addition, endoscopy was performed to confirm the presence of reflux esophagitis. Results: The laboratory findings showed no significant differences between the four groups except for a lower total protein and album level in the DT group after 3 years postoperatively (P=0.006, P=0.033). The percentage of body weight at 1 year, and 3 years postoperatively in the JI group (P=0.013, P=0.011) were significantly less than other groups (P=0.011, P=0.000). The frequency of postoperative symptoms and reflux esophagitis and eating capacity showed no significant differences between the four groups. The GSRS score in the JIP group was significantly better than for the other groups at 1 year, and 3 years postoperatively (P=0.028, P=0.003). Conclusion: We believe that the jejunal pouch interposition is the most useful of the four procedures for improving postoperative quality of life.

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.301-307
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• 2015

High quality transplants are critical for success in crop production. Increasing numbers of growers purchase their transplants from specialized transplant producers instead of growing their own transplants. A drawback of purchasing transplants is the risk of deterioration to transplants during transportation from transplant producers to the growers. This study evaluates the influence of temperature on the quality of grafted tomatoes transplants (Solanum lycopersicum cv. Super Doterang), in order to propose optimum temperature condition for the transportation of grafted tomato transplants. Grafted tomato transplants with visible flower trusses were exposed to different air temperature ($10^{\circ}C$, $25^{\circ}C$, or $40^{\circ}C$) for 2, 4, or 6 hours. After treatment, the NDVI (Normalized Difference Vegetation Index) values of tomato transplants treated at 25 and $40^{\circ}C$ were lower than that at $10^{\circ}C$. The root fresh weight was lowest at $40^{\circ}C$. After transplanting, the transplants that were exposed to the air temperature of $40^{\circ}C$ exhibited chlorosis and blight on lower leaves. The degree of damage on leaves was severer as the high temperature exposure time was longer. The temperature conditions during the transportation also influenced the growth, flowering and fruit set of tomatoes after transplanting. The fruit number and weight of first truss was lowest at $40^{\circ}C$ for 6 hours. Accordingly, it is recommended that the temperature during the transportation should be controlled and kept at the range from 10 to $25^{\circ}C$ even though the period is short (within as six hours) in order to maintain the quality of transplants.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.139-143
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• 2014

This study was conducted to investigate the effect of cultivation period and rockwool block size on the growth and early yield of paprika transplants grown in a closed transplant production system. Paprika seeds were sown and germinated in three different size of rockwool blocks ($45{\times}40{\times}35$, $70{\times}70{\times}60$, $100{\times}100{\times}65mm$) and cultivated in a closed transplant production system for 23, 30, and 37 days after sowing. Paprika transplants were cultivated using $100{\times}100{\times}65mm$ rockwool blocks in a greenhouse following a conventional and typical production method for comparing with the growth of paprika transplants grown in a closed transplant production system. Also, we transplanted paprika transplants grown for 23, 30, and 37 days in a closed transplant production system and greenhouse to rockwool slabs and investigated fresh weight of fruits and yield 125 days after sowing. The growth of paprika transplants grown in $70{\times}70{\times}60mm$ rockwool blocks in a closed transplant production system was highest, and the quality of paprika transplant grown in a closed transplant production system was better than in a greenhouse. Rockwool block size and cultivation period in a closed transplant production system did not affect fresh weight of fruits, however, yield was largest when paprika transplants were cultivated using $70{\times}70{\times}60$ and $100{\times}100{\times}65mm$ rockwool blocks for 23 days in a closed transplant production system. These results suggest that decreasing rockwool block size and cultivation period can be strategically used to enhance transplant quality and yield of paprika, as paprika transplants were cultivated in a closed transplant production system.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.334-342
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• 2016

In order to evaluate the modified installation methods of roof ventilation devices, derived from the previous experiment ('investigation into the optimum capacity of roof ventilation devices and their deployment'), the conventional and modified (improved) roof ventilation systems were installed in the single-span plastic greenhouse for growing oriental melons. The roof vents ($60{\varphi}$) and roof fans (maximum air capacity of $38m^3/min$) were installed in the spacing of 15m (FT, modified 'side vent+roof fan' ventilation) and 6m (TT, modified 'side vent+roof vent' ventilation) respectively on the roof of greenhouses for the modified roof ventilation treatments, and 20m (FC, conventional 'side vent+roof fan' ventilation) and 8m (TC, conventional 'side vent+roof vent' ventilation) for the conventional ones. The stem diameter, leaf blade lengh, petiole length, and leaf width were lower in the FT and TT treatments than those in the conventional treatments, FC and TC. Although the fruit weight and total yields were slightly lower in the FT and TT treatments, the marketable fruit ratio (%) were higher, as a result of increased fruiting ratio (%) in these treatments, than those of FC and TC. The marketable yields (kg/10a) in the FT and TT treatments were 8,391 kg/10a and 7,283 kg/10a, which were respectively 661 kg/10a and 487 kg/10a higher than those in the treatments of FC and TC. The modified installation methods of roof fan resulted in production of more female flowers and lower fruit drop ratio (%) compared to conventional meathods. In the treatment of the conventional ventilation with roof vent, the fruit weight, fruit length & width, and flesh thickness were higher than in other treatments, but there were no significant differences in the fruit width and flesh thickness among the treatments.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.143-150
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• 2017

Effects of packaging methods for maintaining the shelf-life and postharvest quality of Korean chive (Allium tuberosum Rotter) usually called buchu in Korea was studied during fall season. Buchu, which has high moisture content and active metabolism after harvest, is characterized by the greater changes in quality during storage and distribution. It is usually packaged in paper box during distribution in domestic channel in Korea where the marketability ends within few days of harvest. In order to maintain the commercial quality of buchu, we tried to use inner film with or without absorbent paper in commercial paper box packaging. The 'Greenbelt' cultivar of buchu was harvested in october and packaged in corrugated paper box (A), in corrugated paper box with micro-perforated high density polyethylene (HDPE) film as inner material (B), a layer of absorbent paper both at the bottom and top of buchu in corrugated paper box (C) and a combination of HDPE film as inner material along with a layer of absorbent paper both at the bottom and top of buchu in corrugated paper box (D), and stored at $5^{\circ}C$ for up to 21 days. Several quality parameters such as fresh weight loss, respiration rate, color, chlorophyll content and sensory qualities were monitored during storage. When buchu was packaged only in paper box, the appearance and quality deteriorated rapidly through decay development thereby sample became unmarketable within 12 days. On the other hand, buchu packaged with inner HDPE film maintained its quality, good visual appearance and exhibited a longer period of marketable life compared to the samples stored in other treatments. However, the use of absorbent paper did not have any significant effect in maintaining quality of buchu. The uses of inner HDPE film was effective in reducing weight loss that resulted better visual appearance of buchu. Results suggest that the use of inner HDPE film in bulk type corrugated paper box packaging and storing at $5^{\circ}C$ could be the optimum condition for commercial storage of buchu. Further investigation on other quality parameters and packaging methods would be useful in maintaining the quality aspects of buchu at postharvest stages.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.3
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• pp.294-298
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• 2009

A glasshous experiment was carried out in 2002 to evaluate growth differences between two wick types, and to determine the optimum number of wicks in a wick-based hydroponics for production of 'Dejima' seed potatoes (Solanum tuberosum L.). The six minitubers ($7.0{\pm}0.2g$/tuber) produced through aeroponics were planted in a polystyrene box (51 cm long $\times$ 31 cm wide $\times$ 20 cm high) containing growth medium (perlite+peatmoss 1:2, v/v mixtures). Before the boxes were filled with the medium, 6 wicks per box were vertically and 2 to 10 wicks were horizontally installed, respectively, at the bottom of the boxes through holes. Comparing with 6 vertical wick treatment, 6 horizontal wick treatment increased the number of tubers per plant, but decreased average tuber weight. Yield of tubers greater than 5 g (seed potatoes) was not significantly affected by wick type. As the number of the horizontal wicks per box was increased from 2 to 6, the number of seed potatoes increased from 2.8 to 8.0/plant and then leveled off. Average tuber weight increased with increasing the number of the wicks up to 8 and then leveled off. As the number of the wicks per box was increased from 2 to 6, seed potato yield increased from 1.81 to 6.59 kg/$m^2$ and then slowly increased up to 10 wicks per box, reaching 12.9 kg/$m^2$. The results indicate that installing 8 wicks per box ($0.16m^2$) horizontally for the wick culture system in production of 'Dejima' seed potatoes is beneficial considering seed potato yield, cost of wicks, and convenient filling with medium.