• Magazine of the Korean Society of Agricultural Engineers
• /
• v.13 no.4
• /
• pp.2456-2470
• /
• 1971

Compaction of soil is very important for construction of soil structures such as highway fills, embankment of reservoir and seadike. With increasing compaction effort, the strength of soil, interor friction and Cohesion increas greatly while the reduction of permerbilityis evident. Factors which may influence compaction effort are moisture content, grain size, grain distribution and other physical properties as well as the variable method of compaction. The moisture content among these parameter is the most important thing. For making the maximum density to a given soil, the comparable optimum water content is required. If there is a slight change in water content when compared with optimum water content, the compaction ratio will decrease and the corresponding mechanical properties will change evidently. The results in this study of soil compaction with different water content are summarized as follows. 1) The maximum dry density increased and corresponding optimum moisture content decreased with increasing of coarse grain size and the compaction curve is steeper than increasing of fine grain size. 2) The maximum dry density is decreased with increasing of the optimum water content and a relationship both parameter becomes rdam-max=2.232-0.02785 $W_0$ But this relstionship will be change to $r_d=ae^{-bw}$ when comparable water content changes. 3) In case of most soils, a dry condition is better than wet condition to give a compactive effort, but the latter condition is only preferable when the liquid limit of soil exceeds 50 percent. 4) The compaction ratio of cohesive soil is greeter than cohesionless soil even the amount of coarse grain sizes are same. 5) The relationship between the maximum dry density and porosity is as rdmax=2,186-0.872e, but it changes to $r_d=ae^{be}$ when water content vary from optimum water content. 6) The void ratio is increased with increasing of optimum water content as n=15.85+1.075 w, but therelation becames $n=ae^{bw}$ if there is a variation in water content. 7) The increament of permeabilty is high when the soil is a high plasticity or coarse. 8) The coefficient of permeability of soil compacted in wet condition is lower than the soil compacted in dry condition. 9) Cohesive soil has higher permeability than cohesionless soil even the amount of coarse particles are same. 10) In generall, the soil which has high optimum water content has lower coefficient of permeability than low optimum water content. 11) The coefficient of permeability has a certain relations with density, gradation and void ratio and it increase with increasing of saturation degree.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.28 no.2
• /
• pp.216-226
• /
• 1983

Genetic studies on the $F_2$ generation of a set of half diallel crosses involving six cowpea varieties were conducted. by the randomized block design with three replications to determine combining ability, gene action and the relationships between parents and their $F_2$ hybrids. The 12 agronomic characters namely, days to flowering, days from flowering to maturity, days to maturity, diameter of stem, length of internode, number of branches per plant, length of pod, number of pods per plant, number of grains per pod, number of grains per plant, 100 grain weight and grain weight per plot were observed, and the $F_2$ generation of this diallel set of crosses was analysed for each character according to the method by Jinks and Hayman. The results obtained are summarized as follows: 1. Vr-Wr graphical analyses; The following seven characters, days to flowering, number of branches per plant, length of pod, number of pods per plant, number of grains per plant, 100 grain weight and grain weight per plot appeared to be partially dominant, and over dominance was found for days from flowering to maturity, days to maturity, length of internode and number of grains per pod. But diameter of stem indicated partial dominance near complete dominance. 2. Estimates of genetic variance components; In the degree of dominance,. eight characters, that is, days to flowering, days from flowering to maturity, days to maturity, length of internode, number of pods per plant, number of grains per pod, number of grains per plant and grain weight per plot were expressed larger than 1. And the characters, days from flowering to maturity, number of branches per plant and number of grains per plant as the degree of mean dominance ($H_1$/D) were found to be negative value over other characters. On the other hand, apprent asymmetry of dominance-recessive allele ($H_2$ /$4H_1$) produced comparatively estimates with lower value on days from flowering to maturity, length of internode, number of branches per plant and number of grains per pod. 3. Analyses of combining ability; Mean square value of GCA(general combining ability) appeared to be more important than those of SCA (specific combining ability) for most characters, and among them, grain weight per plot showed the highest mean square value in GCA and SCA. 4. Effect of combining ability; Variety 178 was expressed as the highest GCA effects in five characters (days to flowering days to maturity, number of pods per plant, number of grains per plant and grain weight per plot). SCA effects were differed from parents, characters and crosses, but crosses between TVu 1857 $\times$ TVu 2885 and TVu 2702 $\times$ J78 were shown to be highly with SCA effects on yield.

• Journal of Animal Science and Technology
• /
• v.49 no.5
• /
• pp.677-688
• /
• 2007

돼지를 포함한 대부분의 동물은 일정한 발정주기를 가지고 일정한 시기에 배란을 하는 자연배란동물이지만, 토끼, 고양이, 밍크 등의 암놈은 교미자극에 의해 배란이 일어나는 유기배란동물이다. 또한 1년에 한 번만 발정하는 단발정동물과 1년에 수차례 발정하는 다발정동물이 있다. 이 중에서 모돈은 1년에 수차례 발정하는 다발정 동물로서 발정기에 들면 비발정기와는 다른 행동을 나타낸다(Diehl 등, 2001). 양돈가의 수익을 최대화하기 위해서는 비생산일수를 최소로 줄여야 한다. 모돈의 비생산일수를 줄일 수 있는 한 가지 방법은 성공적으로 교배를 시키는 것이다. 이처럼 성공적으로 교배를 시키기 위해서는 수정적기를 정확히 예측해야 한다. 만약 수정적기를 정확히 판단하지 못하여 수태가 되지 않으면, 비생산일수가 늘어나 손실을 입게 된다. 따라서 수정적기를 정확히 판단하는 것은 모돈의 성공적인 인공수정에 있어서 중요한 요소이다. 수정적기는 배란이 일어나기 전 10시간에서 12시간 사이이며, 발정이 시작되는 시점을 기준으로 하였을 때 경산돈의 경우 26시간에서 34시간 사이이고 미경산돈의 경우는 18시간에서 26시간 사이이다(Evans 등, 2001). 현재 하루에 두 번 모돈의 발정을 확인하는 것이 일반화되어 있으며, 이 때 웅돈을 접촉시키거나 육안관찰을 통하여 발정 유무를 판단한다. 이러한 방법에는 숙련된 기술과 풍부한 경험이 요구될 뿐만 아니라 총 소요노동력의 30% 정도가 요구된다(Perez 등, 1986). 하루에 두 번밖에 발정을 감지하지 않기 때문에 발정이 언제 시작되었는지를 정확히 알 수 없으며, 또한 발정의 대부분이 새벽에 시작되므로 수정적기를 정확히 판단하기란 매우 어렵다. 만약 발정을 감지했더라도 적기에 인공수정을 하지 못한다면, 수태율이 낮아지므로 경제적 손실이 초래된다. 현재 이러한 문제점 때문에 2회에서 3회에 걸쳐 인공수정을 하고 있으나 이에 따른 소요비용과 소요노동력 등은 양돈가의 부담을 가중시키는 요인이 되고 있다. 돼지는 발정기가 되면 비발정기에 나타내지 않던 외음부의 냄새를 맡는 행동, 귀를 세우는 행동 및 승가허용 행동 등을 나타낸다(Diehl 등, 2001). 또한 돼지는 비발정기에 비하여 발정기에 더 많은 활동량을 나타낸다(Altman, 1941; Erez and Hartsock, 1990). Freson 등(1998)은 스톨에서 개별적으로 사육되고 있는 모돈의 활동량을 적외선센서를 이용하여 측정함으로써 발정을 86%까지 감지하였다고 보고하였다. 그러나 이 연구는 단지 모돈의 발정을 감지하였을 뿐 번식관리에 있어서 가장 중요한 수정적기의 판단 기준을 제시하지 못하였다. 따라서, 본 연구는 스톨에서 사육되는 모돈의 활동량을 측정함으로써 발정시작시각을 감지하고 이를 기준으로 인공수정적기를 예측할 수 있는 인공수정적기 예측 장치를 개발한 후 이의 성능을 농장실증실험을 통하여 시험하고자 수행되었다.

• Horticultural Science & Technology
• /
• v.19 no.4
• /
• pp.521-525
• /
• 2001

This study investigated the effects of conventional predrying and modified atmosphere (MA) on the head quality and storability of Chinese cabbage 'Norang' cultivar. Immediately after harvest, heads were predried for 2 days and MA stored in $50{\mu}m$ PE film packages at $4^{\circ}C$. MA packaging restrained Hunter L and b values of Chinese cabbage more effectively than non-packaging during storage at $4^{\circ}C$. But there was little change between the two treatments. Fresh weight decreased less in heads treated with predrying and MA than non-treatment during storage. Predried Chinese cabbage heads kept a high level of soluble solids in 4 weeks of storage, while non-packaging maintained high contents of soluble solids for 6 weeks of storage period. Chinese cabbage heads contained 7.0 mg/gFW glucose, 6.3 mg/gFW fructose, and 0.6 mg/gFW sucrose as major soluble sugars at harvest. The content of sugars decreased immediately after predrying and increased steadily after 2 weeks storage. It was found inappropriate to assess head quality of Chinese cabbage by investigating was investigated by Hunter a, firmness, dry matters content, pH, and soluble sugars after predrying and MA package. Marketability of Chinese cabbage was lost when heads were stored at room temperature in 2 weeks. It showed poor appearance of heads stored at $4^{\circ}C$ in 7 weeks. Decay occurred in Chinese cabbage stored in MA under excessive relative humidity. Predried head showed good appearance during storage at $4^{\circ}C$ for 7 weeks. As a result, Chinese cabbage heads can be successfully stored for at least 7 weeks with predrying and MA storage.

• Korean Journal of Veterinary Research
• /
• v.31 no.2
• /
• pp.179-187
• /
• 1991

These studies were carried out to investigate the effects of the size of follicles, semen types, capacitation methods, and additions of hormones, estrous cow serum(ECS), fetal calf serum(FCS), bovine follicular fluid(BFF) and matured cumulus cell(MCC) to the medium on in vitro maturation and fertilization of bovine follicular oocytes. The ovaries were obtained from slaughtered Korean native cows. The follicular oocytes surrounded with cumulus cells were recovered by aspirating follicular fluid from the visible follicles of diameter 3~5mm. The follicular oocytes were cultured in TCM-199 medium containing hormones, FCS, ECS, BFF and MCC for 24~48hrs. in an incubator with 5% $CO_2$ in air at $38.5^{\circ}C$ and then matured oocytes were again cultured for 18~20 hrs. with motile capacitated spermatozoas the TCF (Tyrode calcium free) solution containing $100{\mu}g/ml$ of heparin. The results obtained in these experiments were summarized as follows: 1. The oocytes classified as "A,B,C,D and Degenerative" depending morphological integrity and those 61.4%, 12.1%, 19.2%, 4.2% and 3.0% of the total oocytes recovered, respectively. The maturation and fertilization rate of the A, B, C class follicular oocytes, cultured in the TCM-199 medium supplemented with 10% FCS were 89.1%, 78.0%, 52.6% and 78.1%, 66.1, 33.3%, respectively. 2. The average number of the follicular oocytes recovered from follicles size, 1~2mm, 3~5mm and above 5mm in diameter were 67, 98 and 63, respectively. The maturation and fertilization rate of the follicular oocytes, cultured in the TCM-199 medium were 56.7%, 82.5%, 46.0% and 44.8%, 71.4%, 28.6%, respectively. 3. The fertilization and cleavage rate of the follicular oocytes, inseminated with spermatozoas of epididymal cauda, neat and frozen semen were 63.3%, 73.3%, 70.0% and 32.7%, 37.8% 38.3%, respectively. 4. The fertilization and cleavage rate of follicular oocytes, fertilized with capacitated spermatozoas by heparin, BFF and HIS methods were 70.0%, 53.8%, 34.2% and 38.3%, 23.1%. 17.1%, respectively. And the fertilization and cleavage rate were higher method of heparin. 5. The maturation and fertilization rate of follicular oocytes, cultured in the TCM-199 medium supplemented with 5%, 10%, 15%, 20% and FSH, HCG, 17, $\beta$-estradiol were 76.0~82.3% and 26.2~70.0%, and those values were higher the supplementation than non-supplementation. 6. The maturation and fertilization rate of the follicular oocytes cultured in TCM-199 medium supplemented with 5~20% ECS and FCS were 74.0~80.6%, 26.2~30.0% and 71.7~76.9%, 51.9~58.0%, and the values were higher the supplement of ECS than FCS. 7. The maturation rate (68.0~64.6%) and fertilization rate(59.6~60.4%) of follicular oocytes cultured in TCM-199 medium supplemented with 10% FCS and 20~30% BFF were higher than those of follicular oocytes cultured TCM-199 medium supplemented with 10% FCS and 10% and 50% BFF. 8. The maturation rate(76.5%) and fertilization rate (61.7%) of follicular oocytes cultured in TCM-199 medium supplemented with 10% FCS and $1{\times}10^6/ml$ MCC were higher than those of follicular oocytes cultured in TCM-199 medium supplemented with 10% FCS and $1{\times}10^{{4}{\sim}{5}}/ml$ and $1{\times}10^8/ml$ cumulus cells.

• Horticultural Science & Technology
• /
• v.33 no.3
• /
• pp.303-308
• /
• 2015

The consumption of leaf vegetables has been steadily increasing in Korea. Leaf vegetables are used for "Ssam (vegetable wrap-up), eaf vegetables has been steadily increasing in Korea. Leaf vegetables are used for asoned condiments inside several layers of young vegetable leaves. This study investigated the effect of air temperature on the growth and phytochemical contents of beet (Beta vulgaris L.) and Ssamchoo (Brassica lee L. ssp. namai) grown in a closed-type plant factory system where fluorescent lamps were used as an artificial light source. Seeds of beet and Ssamchoo were sown in a peat-lite germination mix. The roots of 20-day-old seedlings were washed, and the seedlings were planted on a styrofoam board and grown in hydroponic beds for 25 days under fluorescent light. Plants were exposed to one of three different air temperature regimes (20, 25 and $30^{\circ}C$ during the day combined with $18^{\circ}C$ during the night), which were monitored with a sensor at 30 cm above the plant canopy. Increased plant height and leaf area were observed in beet at $25^{\circ}C$ and $30^{\circ}C$ compared to $20^{\circ}C$. For Ssamchoo, the greatest plant height, leaf area, fresh weight and dry weight were obtained at $20^{\circ}C$. Ascorbic acid content of beet and Ssamchoo leaves were highest at $30^{\circ}C$. In beet, total polyphenol and flavonoid contents were higher at $20^{\circ}C$ (42.4, $197.0mg{\cdot}g^{-1}DW$) and $25^{\circ}C$ (46.9, $217.0mg{\cdot}g^{-1}DW$) than $30^{\circ}C$ (22.4, $88.0mg{\cdot}g^{-1}DW$). In Ssamchoo, total polyphenol and flavonoid contents were also higher at $20^{\circ}C$ (79.2, $268.2mg{\cdot}g^{-1}DW$) and $25^{\circ}C$ (66.3, $258.3mg{\cdot}g^{-1}DW$), respectively, than $30^{\circ}C$ (53.7, $134.7mg{\cdot}g^{-1}DW$). Hence, the optimum temperature appears to be $20^{\circ}C$ for growing both beet and Ssamchoo in a closed-type plant factory system with fluorescent light.

• Journal of Mushroom
• /
• v.9 no.4
• /
• pp.186-189
• /
• 2011

The transitivity of Chemical constituents by Pleurotus ostreatus cultivated in different raw sawdusts, which are Juglans mandchurica, Cudrania tricuspidata and Lindera glauca, was investigated. The HPLC chromatography patterns on the chemical constituents of P. ostreatus showed the similar chromatography patterns in all different raw sawdusts and control sawdust. The unknown chemical constituents of P. ostreatus cultivated in the 10%, 20% mixed medium added 10 %, 20% different raw sawdusts, respectively, were increased. But the significance results in the mixed medium added 50% different raw sawdusts were not showed. The chromatography patterns of mycelia grown in media added the 80% MeOH extracts of three tree species showed the similar patterns in comparison with control mycelia. In the results, the secondary metabolites of functional media were not degrade and changed to other derivatives compounds by P. ostreatus.

• Journal of Life Science
• /
• v.22 no.4
• /
• pp.516-523
• /
• 2012

The purpose of this study was to investigate the effect of exercise and/or L-arginine on abdominal fat, IGF-1 on GH/IGF-1 axis, fibrinogen, and PAI-1 in aged and obese rats. Male Sprague-Dawley rats were treated with a D-galactose aging inducing agent (50 mg/kg) given intraperitoneally for 12 weeks. Thirty-two male Sprague-Dawley rats were treated and divided into four groups: aging-high fat diet group (AG+HF), AG+HF with L-arginine intake group (AG+LA), AG+HF with exercise group (AG+EX), and AG+EX with L-arginine intake group (AG+LA+EX). The experimental rats underwent treadmill training (60 min/day, 6 days/week at 0% gradient) for 12 weeks. L-arginine was given orally (150 mg/kg/day) for 12 weeks. After the experiment, blood was collected from the left ventricle and abdominal fat was extracted. The results showed that GH was significantly increased in AG+EX and AG+AL+EX. IGF-1 was significantly increased in both the AG+AL+EX and AG+EX group ($p$<0.05), while fibrinogen and PAI-1 were not significantly different among the groups. Abdominal fat was significantly decreased in the AG+LA, AG+EX, and AG+LA+EX groups ($p$<0.05) compared with the AG+HF group. In conclusion, this study suggests that exercise alone or L-arginine alone or a combination not only increases the GH and IGF-1 concentration, but also decreases the abdominal fat mass.

• Journal of Life Science
• /
• v.22 no.7
• /
• pp.897-903
• /
• 2012

Food allergies have become a serious health concern in the past two decades, especially in developed countries. Foods associated with allergies include vegetables, some fruits, shellfish, wheat, egg, chicken, and nuts. To describe the specific fundamentals, etiological factors, and clinical manifestations, we analyzed the different physical frequency on spleen index in sensitized and regular exercise-trained mice. We also conducted a proliferation assay of lymphocytes to OVA, ROS, ASAS, and we determined the cytokine levels. Female BALB/c mice were bred in the animal laboratory of the P and D university under controlled conditions ($22{\pm}2^{\circ}C$, RH 45-55%, and a 12-hour photoperiod). The animals were 6 weeks old at the start of the study and were fed a standard commercial chow diet from 09:00 to 15:00 for the 8-week study period. All animals had access to distilled deionized water ad libitum. They were divided into four groups: a control group (S; control sensitized, n=25), a low-frequency training group (F2, n=25), a mid-frequency training group (F3, n=25), and a high-frequency training group (F5, n=25) following the treatment of exercise time per week. The results were as follows: The mice spleen index showed the highest grade in the F5 group compared with the other groups; this level showed in an exercise frequency-dependent manner. In the proliferation assay of OVA, the F5 group showed the highest grade compared with the other groups; this level was also showed in an exercise frequency-dependent manner. Peritoneal ROS and ASAS showed a statistically significant increase in the F5 group and decreased in the F2 group compared with the S group. However, there were no significant differences in the F3 group. The highest level of IL-4 was found in the F5 group compared with the other groups. However, the highest level of INF-${\gamma}$ was in the F2 group. The results suggest that FDEIA is positively correlated with the frequency of exercise due to the direct effect of physical exercise on peritoneal ROS and the cytokine profile. Further research is needed on the specific mechanism underlying the combined effects of exercise intensity and frequency on physical-induced allergy anaphylaxis.

• Journal of Nutrition and Health
• /
• v.53 no.3
• /
• pp.231-243
• /
• 2020

Purpose: To determine the metabolic influence of the traditional Korean diet (K-diet), which has been regarded as a healthy diet, we investigated the profile of urine organic acids that are intermediates of various types of metabolism including energy metabolism. Methods: Ten women aged 50-60 years were recruited and randomly divided into 2 diet groups, K-diet and control diet, the latter of which is a Westernized Korean diet that is commonly consumed by Koreans nowadays. Before and after the 2-week intervention, 46 urine organic acids were determined using LC/MS/MS, along with clinical parameters. Results: The average concentrations of succinate (4.14 ± 0.84 ㎍/mg creatinine vs. 1.49 ± 0.11, p = 0.0346) and hydroxymethylglutarate (3.67 ± 0.36 ㎍/mg creatinine vs. 2.97 ± 0.29, p = 0.0466), both of which are intermediates of energy metabolism, decreased in the K-diet group after the 2-week intervention, but these were not observed in the control diet group. In particular, the average concentration of succinate in the K-diet group was lower than that in the control group (3.33 ± 0.56 ㎍/mg creatinine vs. 1.49 ± 0.11, p = 0.0284) after 2 weeks. The concentrations of two tryptophan metabolites, 5-hydroxyindolacetate (3.72 ± 0.22 ㎍/mg creatinine vs. 3.14 ± 0.21, p = 0.0183) and indican (76.99 ± 8.35 ㎍/mg creatinine vs. 37.89 ± 10.06, p = 0.0205) also decreased only in the K-diet group. After the 2-week intervention, the concentration of kynurenate, another tryptophan metabolite, was lower in the K-diet group than that in the control diet group (3.96 ± 0.51 ㎍/mg creatinine vs. 2.90 ± 0.22, p = 0.0356). Interestingly, the urine level of kynurenate was positively correlated with BMI (r = 0.61424, p = 0.0003) and total cholesterol (r = 0.46979, p = 0.0088), which decreased only in the K-diet group (239.40 ± 15.14 mg/dL vs. 198.20 ± 13.25, p = 0.0163). Conclusion: The K-diet alters the urinary excretion of organic acids involved in energy metabolism and tryptophan metabolism, suggesting the influence of the K-diet on these types of metabolism. Urine organic acids changed by the K-diet may serve as biomarkers in future studies.