• Journal of Bio-Environment Control
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• v.2 no.2
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• pp.89-98
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• 1993

The purpose of this study was to investigate crop growth responses under various rain shelters which were devised to improve the indoor environment in summer season. For developing the proper type of rain shelter, the improved rain shelters with the roof of saw - tooth type(saw-tooth type) and 3 span-arch type(improved arch type) were compared with the conventional one with the roof of single arch type(conventional arch type) and no rain shelter (open field ). The results were summarized as follows ; 1. The air temperature in the improved arch type was 4$^{\circ}C$ and 1$^{\circ}C$ lower than those in the conventional arch type and the saw - tooth type, respectively. 2. The air temperature drop by the evaporative cooling + improved drainage was 1.3$^{\circ}C$ which was 0.9$^{\circ}C$lower than that by the improved drainage only. 3. The effect of labour saving in the saw-tooth type was superior to any other type because its frames were used as props and the labour for ventilation was not needed. 4. The highest marketable yield of tomato was 4,897kg/10a in the improved arch type and the total leaf areas which related to photosynthesis was the largest in the saw - tooth type. 5. The improved arch type was proved to be proper to raise yield potential. The effect of the underground environment treatment on the quality and quantity of vegetable showed to be outstanding in the saw- tooth type with the evaporative cooling + improved drainage, and in the improved and conventional arch type with the trickle improved drainage. 6. In conclusion, the saw - tooth type and the improved arch type were proved to be labour saving rain shelters and the indoor environments in both types were better than that in the conventional arch type.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.1
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• pp.1-25
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• 1996

The pathogenesis of atherosclerosis can not be summarized as a single process. Lipid infiltration hypothesis and endothelial injury hypothesis have been proposed and investigated. Recent developments show that there are many points of potential interactions between them and that they can actually be regarded as two phases of a single, unifying hypothesis. Among the many risk factors of atherosclerosis, plasma homocysteine and lipoprotein(a) draw a considerable interest because they are independent indicators of atherogenicity. Triglyceride (TG)-rich lipoproteins (chylomicron and VLDL) are not considered to be atherogenic but they are related to the metabolism of HDL cholesterol and indirectly related to coronary heart disease (CHD). LDL can of itself be atherogenic but the oxidative products of this lipoprotein are more detrimental. HDL cholesterol has been considered to be a favorable cholesterol. The so-called 'causalist view' claims that HDL traps excess cholesterol from cellular membranes and transfers it to TG-rich lipoproteins that are subsequently removed by hepatic receptors. In the so-called 'noncausalist view', HDL does not interfere directly with cholesterol deposition in the arterial wall but instead reflects he metabolism of TG-rich lipoproteins and their conversion to atherogenic remnants. Approximately 70-80% of the human population shows an effective feedback control mechanism in cholesterol homeostasis. Type of dietary fat has a significant effect on the lipoprotein cholesterol metabolism and atherosclerosis. Generally, saturated fatty acids elevate and PUFA lower serum cholesterol, whereas MUFA have no specific effect. EPA and DHA inhibit the synthesis of TG, VLDL and LDL, and may have favourable effects on some of the risk factors. Phospholipids, particularly lecithin, have an antiatherosclerotic effect. Essential phospholipids (EPL) may enhance the formation of polyunsaturated cholesteryl ester (CE) which is less sclerotic and more easily dispersed via enhanced hydrolysis of CE in the arterial wall. Also, neutral fecal steroid elimination may be enhanced and cholesterol absorption reduced following EPL treatment. Antioxidants protect lipoproteins from oxidation, and cells from the injury of toxic, oxidized LDL. The rationale for lowering of serum cholesterol is the strong association between elevation of plasma or serum cholesterol and CHD. Cholesterol-lowing, especially LDL cholesterol, to the target level could be achieved using diet and combination of drug therapy. Information on the link between cholesterol and CHD has decreased egg consumption by 16-25%. Some clinical studies have indicated that dietary cholesterol and egg have a significant hypercholesterolemic effect, while others have indicated no effect. These studies differed in the use of purified cholesterol or cholesterol in eggs, in the range of baseline and challenge cholesterol levels, in the quality and quantity of concomitant dietary fat, in the study population demographics and initial serum cholesterol levels, and clinical settings. Cholesterol content of eggs varies to a certain extent depending on the age, breed and diet of hens. However, egg yolk cholesterol level is very resistant to change because of the particular mechanism involved in yolk formation. Egg yolk contains a factor of factors responsible for accelerated cholesterol metabolism and excretion compared with crystalline cholesterol. One of these factors could be egg lecithin. Egg lecithin may not be as effective as soybean lecithin in lowering serum cholesterol level due probably to the differences of fatty acid composition. However, egg lecithin may have positive effects in hypercholesterolemia by increasing serum HDL level and excretion of fecal cholesterol. The association of serum cholesterol with egg consumption has been widely studied. When the basal or control diet contained little or no cholesterol, consumption of 1 or 2 eggs daily increased the concentration of plasma cholesterol, whereas that of the normolipemic persons on a normal diet was not significantly influenced by consuming 2 to 3 eggs daily. At higher levels of egg consumption, the concentration of HDL tends to increase as well as LDL. There exist hyper-and hypo-responders to dietary (egg) cholesterol. Identifying individuals in both categories would be useful from the point of view of nutrition guidelines. Dietary modification of fatty acid composition has been pursued as a viable method of modifying fat composition of eggs and adding value to eggs. In many cases beneficial effects of PUFA enriched eggs have been demonstrated. Generally, consumption of n-3 fatty acids enriched eggs lowered the concentration of plasma TG and total cholesterol compared to the consumption of regular eggs. Due to the highly oxidative nature of PUFA, stability of this fat is essential. The implication of hepatic lipid accumulation which was observed in hens fed on fish oils should be explored. Nutritional manipulations, such as supplementation with iodine, inhibitors of cholesterol biosynthesis, garlic products, amino acids and high fibre ingredients, have met a limited success in lowering egg cholesterol.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.1
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• pp.1-8
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• 2017

We investigated the effect of silicate coating of rice seeds on bakanae disease incidence and the quality of seedlings raised in seedling boxes and transplanted into pots. The silicate-coated rice seed (SCS) was prepared as follows. Naturally infested rice seeds not previously subjected to any fungicidal treatment were dressed with a mixture of 25% silicic acid at pH 11 and 300-mesh zeolite powder at a ratio of 50 g dry seed - 9 mL silicic acid - 25 g zeolite powder. The following nursery conditions were provided : Early sowing, dense seeding in a glass house with mulching overnight and no artificial heating, which were the ideal conditions for determining the effect on the seed. The nursery plants were evaluated for Gibberella. fujikuroi infection or to determine the recovery to normal growth of infected nursery plants in the Wagner pot. Seedlings emerged 2-3 days earlier for the SCS than they did for the non-SCS control, while damping-off and bakanae disease incidence were remarkably reduced. Specifically, bakanae disease incidence in the SCS was limited to only 7.8% for 80 days after sowing, as compared to 91.6% of the non-SCS control. For the 45-days-old SCS nursery seedlings, the fresh weight was increased by 11% and was two times heavier, with only mild damage compared to that observed for non-SCS. Even after transplanting, SCS treatment contributed to a lower incidence of further infections and possibly to recovery of the seedlings to normal growth as compared to that observed in symptomatic plants in the pot. The active pathogenic macro-conidia and micro-conidia were considerably lower in the soil, root, and seedling sheath base of the SCS. In particular, the underdeveloped macro-conidia with straight oblong shape without intact septum were isolated in the SCS ; this phenotype is likely to be at a comparative etiological disadvantage when compared to that of typical active macro-conidia, which are slightly sickle-shaped with 3-7 intact septa. A active intact conidia with high inoculum potential were rarely observed in the tissue of the seedlings treated only in the SCS. We propose that promising result was likely achieved via inhibition of the development of intact pathogenic conidia, in concert with the aerobic, acidic conditions induced by the physiochemical characteristics associated with the air porosity of zeolite, alkalinity of silicate and the seed husk as a carbon source. In addition, the resistance of the healthy plants to pathogenic conidia was also important factor.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.3
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• pp.223-232
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• 1998

The main experiment related to this report was undertaken to assess the effects of two rates of $Ca(OH)_2$ (0, 250 kg/10a only at establishment) and five rates of $N-P_20_5-K_20$ (0-0-0, 0-10-10, 6-15-15, 12-20-20, 24-25-20 kg/10a/year) on the pasture establishment, forage yield and quality, and vegetation etc. After this 10-year main e experiment pasture had been used to assess the effects of the above treaments on the soil characteristics in oversown hilly pasture of a grass-clover sward. soil properties of mutual ratios of exchangeable cations at d different soil depth, and the visible characteristics of soil conservation obtained are summarized as follows; 1. Compared with the properties of soil fertility and the level for the likelihood grass tetany, the mutual ratios of exchangeable cations in soils; Ca:Mg:K(% of CEC), Ca:Mg:K(K=I), $K/\sqrt{Ca+Mg}$, Mg/K, K/Mg, and Ca/Mg, were discussed at different soil depth. Before and after experiment, these ratios were generally unbalance and unsuitable, and were rather worsened in the order of Mg>Ca>K under the conditions of liming and NPK fertilization without Mg. 2. The ratios of Ca and Ca/Mg were increaby liming, whereas it of $K/\sqrt{Ca+Mg}$ was redused. The ratios of K and $K/\sqrt{Ca+Mg}$ in control and the heavy fertillization of NPK(especially N) were rather lowered than those in the low and medium fertilizations of NPK. 3. The prperties of consevation were closely related with the forage productivity/vegetation rates, as affected by liming and the application rates of NPK. In control of NPK, It was shown to be the worst soil conservation; severly eroded(3rd grade), exporsure of subsoil, redish brown in soil colour, and 18.8% of cobble and stony in covering rate. 4. The improvement of soil conservation was greatly enhanced by increasing the NPK rate. In the medium and heavy fertilizations of NPK, it was shown to be the favorable improvement of soil conservation; slightly eroded(lst grade), covered with humus layer/grass residues in surface soil, dark brown in surface soil colour, under 1% of cobble and stony in covering rate. The increasing of legume yield/vegetation rate by liming rather enhanced the soil conservation of grassland.

• Journal of Distribution Research
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• v.16 no.2
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• pp.95-118
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• 2011

The purpose of this study is as follows. First, we investigate empirically the effects of social network properties such as social network density and centrality of a franchisee on its information sharing with various subjects such as the franchisor and other franchisees in the franchise system. Second, we examine exploratively if tie strength between a franchisee and its franchisor plays a moderating role on the relationship between social network properties and information sharing. The study model was established as shown in

• The korean journal of orthodontics
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• v.38 no.6
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• pp.416-426
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• 2008

The purpose of this study was to evaluate the mobility and ratio of the bone-implant contact (BIC) of a sandblasted, large grit and acid-etched (SLA) orthodontic micro-implant. Methods: Ninety-six micro-implants (48 SLA and 48 machined) were implanted in the upper and lower buccal alveolar bone, and palatal bone of four beagle dogs. Two weeks after surgery, orthodontic force (150-200 g) was applied. Two beagles were sacrificed at 4-weeks and the other two at 12-weeks. Histomorphometric comparisons were made between the SLA experimental group and the machined micro-implant as a control group to determine the ratio of contact between the bone and implant. Micro-implant mobility was also evaluated using $Periotest^{(R)}$. Results: Periotest values showed no statistically significant difference in the upper alveolar and palatal bone between groups except for the lower buccal area. BIC in the upper buccal area showed no significant difference between groups both at 4-weeks and 12-weeks. However, both the groups showed a significant difference in BIC ratio in the rest of the experimental areas between 4 weeks and 12 weeks. The experimental group showed active bone remodeling around the bone-implant interface compared to the control group. Conclusions: There were significant differences in the BIC and the Periotest values between the surface-treated and machined micro-implants according to bone quality in the early stage.

• Korean Journal of Agricultural Science
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• v.6 no.1
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• pp.56-64
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• 1979

Two types of fiat-plate collector were designed and constructed for utilizing the solar energy as heating source of red pepper drying. It was performed to investigate the basic factors on using the collectors and the drying effect on various types of red pepper, and the results obtained are summarized as follows. 1. The optimum tilted angles of the collector in Daejeon area were ${\phi}-15^{\circ}$ in summer season and ${\phi}+15^{\circ}$ in winter season when it was adjusted two times per a year: 2. In the conditions during experiment period, average atmospheric temperature and relative humidity were $25.6^{\circ}C$ and 52.6%, respectively, and $42.0^{\circ}C$, 74.2% in the control chamber. The temperature in the drying chamber connected to the water heater was the highest but relative humidity in the chamber connected to the air heater was the lowest among the chambers. 3. The drying velocity of whole red pepper in the chamber connected to the water heater was the fastest as 2.3 times as compared to the whole type on the mat drying followed by air heater and control in decreasing order. The horizontally cut red pepper in the chamber connected to the water heater was dried exceedingly fast among twelve plots. 4. The content of capsaicine as pungent principle and of capsanthine as red pigment in the red pepper were reduced during drying but there were no differences significantly on the drying method, and it could not affect much on the quality of dried product.

• Journal of Plant Biotechnology
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• v.44 no.4
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• pp.438-447
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• 2017

Flowering is one of the most important development traits related to the production of Brassica rapa crops. After planting, a sudden low temperature triggers premature flowering, which leads to a reduction in the yield and quality of harvested production. Therefore, understanding the mechanism of flowering control is important in the agricultural productivity for preventing Brassica rapa crops. Vernalization is generally known as the main factor of flowering in the Brassica plant. However, in the subspecies of Brassica rapa, some accession such as Yellow sarson and Komatsuna display the flowering phenotype without vernalization. Circadian genes, which diurnally regulate plant physiology, have a role for photoperiodic flowering but are related to the regulation of the vernalizarion mechanism. In this report, the 22 B. rapa accession were divided into two groups, vernalization and non-vernalization, and the sequenced circadian gene, BrPRR1s. Among them, the BrPRR1b gene was found to have deletion regions, which could classify the two groups. The PCR primer was designed to amplify a short band of 422bp in the vernalization type and a long band of 451bp in the non-vernalization type. This primer set was applied to distinguish the flowering types in the 43 B. rapa accession and 4 Brassica genus crop, Broccoli, cabbage, mustard, and rape. The PCR analysis results and flowering time information of each crop demonstrated that the primer set can be used as marker to discern the flowering type in Brassica crops. This marker system can be applied to the B. rapa breeding when selecting the flowering character of new progenies or introducing varieties at an early stage. In addition, these results displayed that the circadian clock genes can be a good strategy for the flowering control of B. rapa crops.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.6
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• pp.449-469
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• 2011

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering during 2010. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery, and new and renewable energy. Various topics were presented in the field of general thermal and fluid flow. Research issues mainly focused on the thermal reliability of axial fan and compressor in the field of fluid machinery. Studies on the design of ground source heat pump systems and solar chemical reactors were executed in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (3) Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and CO2 were studied. Performance improvement of refrigeration systems are tried applying various ideas of refrigerant subcooling, dual evaporator with hot gas bypass control and feedforward control. The hybrid solar systems combining the solar collection devices with absorption chillers or compression heat pumps are simulated and studied experimentally as well to improve the understanding and the feasibility for actual applications. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. Various studies on heating and cooling systems, HVAC facilities, indoor air environments and energy resources were carried to improve the maintenance and management of building service equipments. In the field of heating and cooling systems, papers on a transformer cooling system, a combined heat and power, a slab thermal storage and a heat pump were reported. In the field of HVAC facilities, papers on a cooling load, an ondol and a drying were presented. Also, studies on HVAC systems using unutilized indoor air environments and energy resources such as air curtains, bioviolence, cleanrooms, ventilation, district heating, landfill gas were studied. (5) In the field of architectural environment and energy, studies of various purposes were conducted such as indoor environment, building energy, renewable energy and green building. In particular, renewable energy and building energy-related researches have mainly been studied reflecting the global interest. In addition, many researches which related the domestic green building certification of school building were performed to improve the indoor environment of school.

• Environmental and Resource Economics Review
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• v.14 no.1
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• pp.167-199
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• 2005

The following policy implications can be drawn from this study: 1) The Air Pollution Emission Amount Report published by the Ministry of Environment since 1991 classifies industries into 4 sectors, i. e., heating, manufacturing, transportation and power generation. Currently, the usability of report is very low and extra efforts should be given to refine the current statistics and to improve the industrial classification. 2) Big pollution industries are as follows - s7, s17 and s20. The current air pollution control policy for these sectors compared to other sectors are found to be inefficient. This finding should be noted in the implementation of future air pollution policy. 3) s10 and s17 are found to be a big polluting industrial sector and its pollution reduction effect is also significant. 4) The effect of emission coefficient (${\Delta}f$) has the biggest impact on the reduction of emission amount change and the effect of economic growth coefficient (${\Delta}y$) has the biggest impact on the increase of emission volume. The effect of production technology factor (${\Delta}D$) and the effect of the change of the final demand structure (${\Delta}u$) are insignificant in terms of the change of emission volume. 5) Further studies on emission estimation techniques on each industry sector and the economic analysis are required to promote effective enforcement of the total volume control system of air pollutants, the differential management of pollution causing industrial sectors and the integration of environment and economy. 6) Korea's economic growth in 1990 is not pollution-driven in terms of the Barry Commoner's hypothesis, even though the overall industrial structure and the demand structure are not environmentally friendly. It indicates that environmental policies for the improvement of air quality depend mainly on the government initiatives and systematic national level consideration of industrial structures and the development of green technologies are not fully incorporated.