• The Korean Journal of Mycology
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• v.4 no.1
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• pp.31-44
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• 1976

The studies were carried out to examine the effects of supplementation of nutritional substances and physical conditions in substrate on the mycelial growth and yield of fresh sporophores of winter mushroom, Flammulina velutipes(Curt. ex Fr.) Sing. and to obtain further informations on the nutritional requirements of the fungus with reference to improvement of substrate through [analysis of chemical composition of the substrates during the cultivation period. The results obtained are summarized as follows: 1. The best yield of fresh sporophores, 84.4 g per 280 g substrate in a bottle, was obtained from the mixture of poplar sawdust 10 and rice bran 3 by volume when Flammulina velutipes was cultivated on the poplar sawdust supplemented by rice bran, wheat bran, cattle manure and various combinations of these materials as nutrient sources. The substrates of poplar sawdust 10 plus rice bran 3 and 2 or wheat bran 3 with a higher yield of fresh sporophores showed a comparatively higher content of total nitrogen. total sugar, and potassium. 2. The mycelial growth of the fungus was compared on the substrates of poplar sawdust supplemented by the several nutrient sources and poplar sawdust alone. The fastest linear growth occurred on substrates of poplar sawdust alone and poplar sawdust plus cattle manure deficient in sugar and nitrogen sources, but mycelial density was more sparse on the substrates. Also, growth in a solution extracted from these substrates was very meager. 3. In the substrates which varied with bulk density and moisture content optimum bulk density and moisture content for mycelial growth was 0.2g/cc and 72% on a dry weight basis, respectively, but the highest yield of fresh sporophores was obtained at the bulk density of 0.3g/cc and moisture content of 67%. 4. By increasing the ratio of rice bran in poplar sawdust the loss of total weight and ash, content at each stage was increased, and during the cultivation period of 75 days, loss of total weight of the substrates at inoculation was 17.8 to 28.8% and ash content increased about 12%. 5. 11 to 14% of the cellulose and 3 to 4% of the lignin content per original substrate were decreased without a great difference depending of the mixing ratio of rice bran. The soluble glucose concentration in the substrates was increased during the same period. 6. In the process of vegetative and reproductive growth of the fungus upon the substrates, the total nitrogen was increased in quantity per dry weight of sample but was reduced in absolute quantity to a minute extent. There is no great changes in content of organic nitrogen including amino acid nitrogen, and hydrolysable ammonium nitrogen during the vegetative growth period, but occurrence of sporophores resulted in a decrease in the nitrogen content of these forms. On the one hand, by an increase of additive amounts of rice bran, nitrogen contents of these forms were higher and the reduction range during the reproductive growth period became wider. 7. Mycelial growth of the fungus was accelerated in various liquid media supplemented with organic nitrogen sources such as peptone and yeast extract in comparison with addition of inorganic nitrogen sources. Furthermore, mycelial growth was mere vigorous in the media with higher content of organic nitrogen sources.

• Journal of Korean Society of Forest Science
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• v.64 no.1
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• pp.11-19
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• 1984

Potted, germinating Pinus rigida ${\times}$ P. taeda seedlings were inoculated with Pisolithus tinctorius (Pt) ectomycorrhizal fungus to test the effectiveness of Pt in relation to organic amendment and changes in soil fertility and soil texture. Pt was cultured as mycelia in vermiculite-peat moss mixture with nutrients and added to sterilized pot soils with or without organic amendment (fully fermented compost) at three soil texture levels (sand, loamy sand, and sandy loam) in a factorial design. Plants were grown in a greenhouse for 4 months and harvested to compare their growth with non-mycorrhizal plants and plants infected by natural fungi. Regardless of sod texture, soil fertility, or organic amendment, seedlings inoculated with Pt were better in dry weight and height than non-mycorrhizal plants or those infected by natural fungi. An exception was observed in the most fertile soil (0.075% N and 1.32% organic matter content in sandy loam with organic amendment), where non-mycorrhizal plants were slightly bigger (8%) and heavier (18%) than Pt-inoculated plants. In over-all average, Pt-inoculated seedlings were 30% taller and 107% heavier than those infected by natural fungi and 31 % taller and 60% heavier than non-mycorrhizal plants. Growth stimulation of seedlings by Pt was more pronounced in less fertile sand soil when organic was not amended. Mycorrhizal frequency of Pt (% of mycorrhizal root tips) was reduced to about half (from 84 to 33% in sandy loam and from 77 to 40% in loamy sand) by organic amendment, while that of natural fungi was not significantly affected. Severe nitrogen deficiency was observed in the needles of non-mycorrhizal plants (1.38% N), while both Pt-inoculated plants (1.68% N) and those infected by natural fungi (1.89% N) did not develop symptom, suggesting an active role of mycorrhizae in absorption of soil nitrogen. Top to root ratio increased with organic amendment to non-mycorrhizal plants, but was not significantly affected by fungal treatment. It was concluded from this study that relative effectiveness of Pt was determined by soil fertility. Organic amendment to less fertile sand soil increased effectiveness of Pt, while the same amendment to more fertile loamy sand and sandy loam decreased effectiveness of Pt. Benefits of Pt mycorrhizae would be expected most either when organic was not added to the soil, or when soil nutrients were not abundant.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.1
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• pp.78-88
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• 1985

Nitrogen fertilizer effectiveness on rice production was studied to evaluate the different forms and sources. Seven kind of nitrogen fertilizers were applied in two levels, 15 and 30 kg per 10a on Jinjubyeo (Japonica type) in silt loam paddy soil of pot cultivation. The results were summerized as follows; 1. pH in soils was decreased with enhancement of ammonium sulfate application in $NH_4-N$, but it was increased with times after nitric-acid application and PH change in soil was not remarkable when $NO_3-N$ with accessory component was applied. 2. $NH_4-N$ contents in soil were the lowest at 2 weeks after application in N 15kg/10a regardless of different sources of nitrogen fertilizer. $NO_3-N$, in N 30kg/10a, was decreased continuously until 4 weeks, while $NH_4-N$, Urea-N were at minimum during 2-3 weeks. 3. Growth of culm length and straw weight applied with AN (Ammonium Nitrate), AS (Ammonium Sulfate) and urea were superior to the form of nitrate. While NA (Nitric Acid), PN (Potassium Nitrate) and CN (Calcium Nitrate) plot of the $NO_3-N$ was the dominant fertilizers for root elongation. 4. Brown rice yields were increased dominantly by $NH_4-N$ application such as AS or AP than $NO_3-N$ pot. But the yields in case of $NO_3-N$ application CN, PN and NA were decreased. 5. N, P, Mg and Mn content of straw ranked the effectiveness of nitrogen forms as $NH_4-N$, Urea-N and $NH_4-N+NO_3-N$, while K, Ca and $SiO_2$ content of straw in $NO_3-N$ fertilizer plot were high while N, P, Mg, Mn, Fe and Mg were low. 6. Increament of nitrogen absorption in straw was stimulated by enhancement of phosphorous absorption and the growth and yield of rice plant were increased. Absorption of N, P, Ca and Mg was decreased by CN application. Absorption of N, P and Mg also was decreased by $NO_3-N$ application and N, P, Mg or Ca content were seemed to simulated the growth and yield of rice plant. 7. $SiO_2$, Zn and Fe contents of the root at harvest stage were higher than those of the straw. N, P, Mg, Mn, Zn and Fe contents were high in $NH_4-N$ and Urea treatment. While K, ca and $SiO_2$ contents, however, were high in $NO_3-N$ treatment.

• KDI Journal of Economic Policy
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• v.12 no.3
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• pp.71-94
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• 1990

This paper reviews the rationale of monetary and banking intervention by an outside authority, either the government or the central bank, and seeks to delineate clearly the optimal limits to the monetary and banking deregulation currently underway in Korea as well as on a global scale. Furthermore, this paper seeks to establish an objective and balanced view on the role of the central bank, especially in light of the current discussion on the restructuring of Korea's central bank, which has been severely contaminated by interest-group politics. The discussion begins with the recognition that the modern free banking school and the new monetary economics are becoming formidable challenges to the traditional role of the government or the central bank in the monetary and banking sector. The paper reviews six arguments that have traditionally been presented to support intervention: (1) the possibility of an over-issue of bank notes under free banking instead of central banking; (2) externalities in and the public good nature of the use of money; (3) economies of scale and natural monopoly in producing money; (4) the need for macro stabilization policy due to the instability of the real sector; (5) the external effects of bank failure due to the inherent instability of the existing banking system; and (6) protection for small banknote users and depositors. Based on an analysis of the above arguments, the paper speculates on the optimal role of the government or central bank in the monetary and banking system and the optimal degree of monetary and banking deregulation. By contrast to the arguments for free banking or laissez-faire monetary systems, which become fashionable in recent years, monopoly and intervention by the government or central bank in the outside money system can be both necessary and optimal. In this case, of course, an over-issue of fiat money may be possible due to political considerations, but this issue is beyond the scope of this paper. On the other hand, the issue of inside monies based on outside money could indeed be provided for optimally under market competition by private institutions. A competitive system in issuing inside monies would help realize, to the maxim urn extent possible, external economies generated by using a single outside money. According to this reasoning, free banking activities will prevail in the inside money system, while a government monopoly will prevail in the outside money system. This speculation, then, also implies that the monetary and banking deregulation currently underway should and most likely will be limited to the inside money system, which could be liberalized to the fullest degree. It is also implied that it will be impractical to deregulate the outside money system and to allow market competition to provide outside money, in accordance with the arguments of the free banking school and the new monetary economics. Furthermore, the role of the government or central bank in this new environment will not be significantly different from their current roles. As far as the supply of fiat money continues to be monopolized by the government, the control of the supply of base money and such related responsibilities as monetary policy (argument(4)) and the lender of the last resort (argument (5)) will naturally be assigned to the outside money supplier. However, a mechanism for controlling an over-issue of fiat money by a monopolistic supplier will definitely be called for (argument(1)). A monetary policy based on a certain policy rule could be one possibility. More importantly, the deregulation of the inside money system would further increase the systemic risk inherent in the current fractional banking system, while enhancing the efficiency of the system (argument (5)). In this context, the role of the lender of the last resort would again become an instrument of paramount importance in alleviating liquidity crises in the early stages, thereby disallowing the possibility of a widespread bank run. Similarly, prudential banking supervision would also help maintain the safety and soundness of the fully deregulated banking system. These functions would also help protect depositors from losses due to bank failures (argument (6)). Finally, these speculations suggest that government or central bank authorities have probably been too conservative on the issue of the deregulation of the financial system, beyond the caution necessary to preserve system safety. Rather, only the fullest deregulation of the inside money system seems to guarantee the maximum enjoyment of external economies in the single outside money system.

• The Korean Journal of Air & Space Law and Policy
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• v.32 no.1
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• pp.225-285
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• 2017

In regard to the regulations related to the RPA(Remotely Piloted Aircraft), which is sometimes called in other countries as UA(Unmanned Aircraft), ICAO stipulates the regulations in the 'RPAS manual (2015)' in detail based on the 'Chicago Convention' in 1944, and enacts provisions for the Rules of UAS or RPAS. Other contries stipulates them such as the Federal Airline Rules (14 CFR), Public Law (112-95) in the United States, the Air Transport Act, Air Transport Order, Air Transport Authorization Order (through revision in "Regulations to operating Rules on unmanned aerial System") based on EASA Regulation (EC) No.216/2008 in the case of unmanned aircaft under 150kg in Germany, and Civil Aviation Act (CAA 1998), Civil Aviation Act 101 (CASR Part 101) in Australia. Commonly, these laws exclude the model aircraft for leisure purpose and require pilots on the ground, not onboard aricraft, capable of controlling RPA. The laws also require that all managements necessary to operate RPA and pilots safely and efficiently under the structure of the unmanned aircraft system within the scope of the regulations. Each country classifies the RPA as an aircraft less than 25kg. Australia and Germany further break down the RPA at a lower weight. ICAO stipulates all general aviation operations, including commercial operation, in accordance with Annex 6 of the Chicago Convention, and it also applies to RPAs operations. However, passenger transportation using RPAs is excluded. If the operational scope of the RPAs includes the airspace of another country, the special permission of the relevant country shall be required 7 days before the flight date with detail flight plan submitted. In accordance with Federal Aviation Regulation 107 in the United States, a small non-leisure RPA may be operated within line-of-sight of a responsible navigator or observer during the day in the speed range up to 161 km/hr (87 knots) and to the height up to 122 m (400 ft) from surface or water. RPA must yield flight path to other aircraft, and is prohibited to load dangerous materials or to operate more than two RPAs at the same time. In Germany, the regulations on UAS except for leisure and sports provide duty to avoidance of airborne collisions and other provisions related to ground safety and individual privacy. Although commercial UAS of 5 kg or less can be freely operated without approval by relaxing the existing regulatory requirements, all the UAS regardless of the weight must be operated below an altitude of 100 meters with continuous monitoring and pilot control. Australia was the first country to regulate unmanned aircraft in 2001, and its regulations have impacts on the unmanned aircraft laws of ICAO, FAA, and EASA. In order to improve the utiliity of unmanned aircraft which is considered to be low risk, the regulation conditions were relaxed through the revision in 2016 by adding the concept "Excluded RPA". In the case of excluded RPA, it can be operated without special permission even for commercial purpose. Furthermore, disscussions on a new standard manual is being conducted for further flexibility of the current regulations.

• Journal of Technologic Dentistry
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• v.17 no.1
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• pp.41-57
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• 1995

This study was conducted to collect and analyze previous information in order to manage efficience, improve experience effect and promote employment rate. The questionnaire interview with 27 chief of dental Laboratory refered clinical experience in technology department about clinical experience in 14 Jumior colleges were also investigated. The results were summarried as follows : The portion of age of 35-39 among chief of dental Laboratory was 40.7% which was the highest, that of male was 96.3%, that of junior college graduate was 97.5%, that of 10years experience was 92.6% and that of ceramic technician was 85.2%, 63.0% dental laboratory for clinical experience was a bore space of 30pyong. Aspect of dental laboratory management, manufacturing all part of prosthetic restoration was 29.6%, othodontic appliance and ceramic restoration was 7.4%, 3.8%, each. The percentage of 40.7 was having connection with 30-3a dental clinics and referring case per day was 10-19 cases(40.7%), manufacturing time of referred prosthetic restoration was 3-4 days(77.8%), places preparing seminar room for education was 29.6%, above a place of 40pyong was 11.1% 30-34 pyong and 35-39 pyong was 7.4% each. During training of 2 years education course student, 18.5% was rack of thorough occupational career. While 44.4% will want the more salary among 3years education course student, 74.1% will expect the more dental techmicians would engaged in their field, 51.9% will hope improve of their theory and practice, 29.6% be expected better skill and 14.8% be expected better theory. Attitude of clinical experience places was distributed by 59.3% of offering only experience chance, 25.9% of wasting time and 29.0% of annoying. The big emphasis of climical experience was thorough occupational career(44.4%). The clinical experience places of our college were selected after direct visiting, so their condition of management was not that bad but most of dental laboratory were poor in management state and working environment. Therefore it is difficult to choose appropriate places and dental Laboratory are also limited manpower and time as suppliers. So that it recommended to induce flexible management of experience period by interval and rotation of experience places among college and to applicate intern-system for employment ant industry-college cooperation aspect.

• Journal of Korean Society of Forest Science
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• v.51 no.1
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• pp.56-65
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• 1981

The training of forest ranger level and forest worker level to push the sound forest management and to increase the employment effects in forestry will be done without delay as soon as possible. So several opinions to be considered are here discussed. 1. The ranger level will be at first completely trained with the technics developed and modernized, to process really the sound forest management based on the concept of ecological and economical technic. 2. The organization of vocational training and it's systematical training method will be newly adopted to increase the labour efficiency in forestry. The case of fulltime worker level should be more intensively trained and part-time worker or forest famer level should be trained by the forest ranger and skilled worker with visiting circularly their working place. And the daily employed workers and village people for working should be done by the skilled workers. 3. The training subjects for them at the beginning step will be exploited by the instructors and concerned experts with studying their current conditions. Their practical training is more reasonable to do in the practically managing forest and to carry out under the responsible of leader of this forest. 4. The instructors included rangers of training forest will get specially certain intensive training through the aids of outside experts or through the group instruction with them. 5. The training fields and their reasons to be learned by them are discussed in this paper from the basic knowledge to the skill technics. 6. In oder to systematize and mordernize more rapidly our forest technics that need for training them and also applying directly in the forest management, a total effort of certain type by scientists and technicians scattered individually all over the country is now earnestly demanded to synthesize their knowledge, technic and experience. So to do like this, the establishment of certain organization through which can do their total efforts together will be considered and assisted by the concerned authority. 7. For better lieving of full-time workers, the whole-round year working amount have to be supplied though the work technic-and working plan development. And under the conditions that the timber harvesting work is still not so enough and it has a bad climatic season, the in-side working system and side - job aids will be developed for their sound lieving. 8. The organization of labour management will be soon introduced in the concerning administrativ authority to solve the forest labour problems and to increase the employing effects in forestry in future. 9. The supply programm of improved and trained tools and maschines for forest work is also considered to use by the trained persons. If not to do so, the training results will return to the original condition and will get nothing any more.

• Journal of Korean Society of Forest Science
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• v.13 no.1
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• pp.25-39
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• 1971

Recently successful induction of haploid plant by means of anther culture method has become a big topic among geneticists and plant breeders. The haploid plant can be used as a precious material for such basic researches as mutation or genetics. Once the haploid is obtained, production of homozygous plant is not a difficult problem. The method of producing homozygous plant can, also, be applied to the practical breeding works. When applied to the hybridization of self-fertilizing breeding period would be greatly shortened and in cross-fertilizing vegetables production of uniform hybrid seed would be very easily obtained. Last few years many scientists attempted anther cultures using various plant species, but it was successful only in several species. Unlike the other tissue cultures which use somatic organs or tissues as explants, anther culture seems to be very difficult because the plants or calli have to be induced from the haploid microspores or pollen grains. In the present experiment anther culture of fruit trees and ornamental shrubs of four genera and seven species was attemped. Anthers of Various stages ranging from tetrad and late microspore were cultured on the modified Murashige and Skoog's medium supplemented with various concentrations of auxins and kinetin as growth regulators. Handling of materials, sterilization, and other operations of culture were done by routine methods. The results were summarized as follows: 1. Calli were induced in the anthers of Forsythia Koreana Nak., Rhododendron mucronuratum Turcz., R. yedoense Max. var. Poukhanense Nak., and Prunus armeniaca L. var. ansu Max. No signs of callus were observed in Prunus persica Sieb. et Zucc. var. vurgaris Max., Pyrus ussuriensis var. macrostipes (Nak.), and Prunus salcina Lindley. 2. Calli were easily formed in any of the media with differing concentrations of auxins and kinetin. 3. In F. Koreana calli developed from anther surface and connective. Callus emerging out of anther locule was not observed. 4. Somatic calli arose from filament, connective, and inside of anther wall in R. mucronulatum. Many of the microspores accumulated starch grains. 5. The anther lobes located opposite the filament of R. yedoense turned easily to calli. This phenomenon was not observed in R. mucronulatum. Microspore embedded for a period in the medium became starch pollen. No callus was observed arising from microspore. 6. In P. armeniaca calli were not induced from somatic anther tissues. Instead, callus emerged out of anther locule rupturing the anther slit. Starch was not formed in the microspore. 7. In P. persica, Pyrus ussuriensis, and P. salcina, calli were not observed in the anthers examined more than 60 days after culture. Microspores of these species, however, were free of starch grains even after long period of subculture. 8. It was learned that somatic calli of the species examined arose usually from endothelium of anther wall, septum of two neighboring anther locules, parenchyma tissues of connectives, or anther lobes. 9. In the anther locule of P. armeniaca cultured long in medium, swollen microspores, polynucleate microspores, multicellular pollen grains, or callus mass were frequently observed, this indicating that the callus of this species was microspore-origin. 10. It was clarified that in P. armeniaca production of haploid plant by anther culture might be possible.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.12
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• pp.1589-1598
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• 2008

The objective of this study was to investigate the effect of obesity on health by analyzing the factors which are related to obesity through the questionnaires on the dietary pattern, nutrient intake and physical measurements. The subjects, 419 college women aged 20 to 24 year-old, were randomly selected from Seoul and data were collected during March to May, 2008 and classified as under underweight, normal weight, and obesity groups according to BMI. However, weight, skeletal muscle mass, body fat mass, fat free mass, percentage of body fat, and waist to hip ratio showed significant differences among all the groups (p<0.05). In the obese group, 77.8% ate fat-rich foods such as galbi and samgyopsal more than two times per week, 66.7% ate vegetables other than kimchi (p<0.05) as compared to the underweight and normal groups by mini dietary assessment (p<0.05). The cholesterol intakes of the underweight, normal weight, and obese groups were $164.67{\pm}114.52mg/dL$, $143.31{\pm}99.58mg/dL$, and $121.92{\pm}54.91mg/dL$, respectively, and the obese group had a significantly lower intake than the other groups (p<0.05). The serum total cholesterol levels of the underweight, normal, and obese groups were $177.04{\pm}26.36mg/dL$, $189.46{\pm}29.05mg/dL$, and $170.00{\pm}12.75mg/dL$, respectively, and the obese group showed lower total cholesterol level than the other groups (p<0.05). The triacylglycerol level of the obese group ($132.00{\pm}64.60mg/dL$) was significantly higher than the other two groups (p<0.05). The HDL-cholesterol levels of the underweight, normal weight, and obese groups were $51.92{\pm}9.39mg/dL$, $59.20{\pm}13.53mg/dL$, and $43.00{\pm}8.98mg/dL$, respectively, showing that the obese subjects had significantly lower HDL-cholesterol levels as compared to the subjects in the other groups (p<0.05). The HDL-C/LDL-C ratios of the underweight ($0.52{\pm}0.45$) and normal weight ($0.59{\pm}0.23$) groups were higher than the ratio of the obese group ($0.41{\pm}0.06$). Total cholesterol were positively correlated with LDL-cholesterol (r=0.768, p<0.01), but triacylglycerol were adversely correlated with HDL-cholesterol. In conclusion, our results show that college-aged women in Seoul should be encouraged to amend their overall dietary habits, make a dietary plan that fits their individual needs, and maintain an effective exercise schedule.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.826-836
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• 2010

This study was conducted to compare the dietary habits, nutrient intake and health status of female college students at Sahmyook University according to their majors. Specifically, women majoring in literature and science (77), food and nutrition (103) and sport (73) were evaluated. College women in the sports department were more likely to have a part-time job and had greater expenses than women in the other departments. The average height of college women in the sports department (164.3${\pm}$4.6 cm) was 2.04 cm taller than that of women with other majors (162.3${\pm}$4.7 cm). College women in the department of literature and science were more likely to have an unbalanced diet, even though they commonly ate small amounts of fruit as snacks. They were more prone to take nutrient tablets and vitamins when compared to women in the other departments. College women in the department of sport were more likely to have unbalanced meals (31.5%) and to overeat. Students in the department of food and nutrition ate more fruit, vitamin C and E but less cholesterol containing foods (p<0.05), less fast food and fried food than students in the other departments. The subjects in the department of sport ate less bread, sweet potatoes, fast foods and fried foods but more calories, fat, vitamin A, vitamin B, niacin, Ca, P and cholesterol than students in the other departments (p<0.05). They were also more likely to exercise for more than two hours a day. The most common problems among college women were going without meals, eating an unbalanced diet, overeating, intake of ill-balanced nutrients and lack of exercise. It was found that college women in the department of sport had a better intake of nutrients and maintained healthier life styles.