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Studies on Combining Ability and Inheritance of Major Agronomic Characters in Naked Barley (과맥의 주요형질에 대한 조합능력 및 유전에 관한 연구)

  • Kyung-Soo Min
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.23 no.2
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    • pp.1-24
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    • 1978
  • To obtain basic information on the breeding of early maturing, short culm naked-barley varieties, the following 10 varieties, Ehime # 1, Shikoku #42, Yamate hadaka, Eijo hadaka, Kagawa # 1, Jangjubaeggwa, Baegdong, Cheongmaeg, Seto-hadaka and Mokpo #42 were used in diallel crosses in 1974. Heading date, culm length and grain yield per plant for the parents, $F_1's$ and $F_2's$ of the 10X10 partial diallel crosses were measured in 1976 for analysis of their combining ability, heritability and inheritance. The results obtained are summarized below; 1. Heritabilities in broad sense for heading date, culm length and grain yield per plant were 0.7831, 0.7599 and 0.6161, respectively. Narrow sense heritabilities for heading date were 0.3972 in $F_1$ and 0.7789 in $F_2$ and for culm length 0.6567 in $F_1$ and 0.6414 in $F_2.$ These values suggest that earliness and culm length could be successfully selected for in the early generations. Narrow sense heritability for grain yield was 0.3775 in $F_1$ and 0.4170 in $F_2.$ 2. GCA effects of the $F_1$ and $F_2$ generations for days to heading were high in the early direction for early-heading varieties, while for late-heading varieties the GCA effects were high in the late direction. Absolute values for GCA effects in $F_1$ were higher than in $F_2.$ SCA effects of the $F_1$ and $F_2$ generations were high in the early-heading direction for Shikoku # 42 x Mokpo # 42, Ehime # 1 x Yamate hadaka, Shikoku # 42 x Yamate hadaka and Shikoku #42 x Eijo hadaka. 3. The GCA effects for culm length in the $F_1$ and $F_2$ generations for tall varieties were high in the tall direction while short varieties were high in the short direction. Absolute values for the GCA effects in $F_1$ were higher than in $F_2.$ SCA effects were high in the short direction for the combinations of Mokpo # 42 with Ehime # 1, Yamate had aka and Eijo hadaka. 4. The GCA effects for grain yields per plant in the $F_1$ and $F_2$ generations for varieties with high yields per plant were high in the high yielding direction, while varieties with low yields per plant were high in the low yielding direction. Absolute values of the $F_1$ GCA effects were higher than the $F_2$ effects. The combinations with high SCA effects were Mokpo # 42 x Shikoku # 42, Mokpo # 42 x Seto hadaka and Mokpo # 42 x Cheongmaeg. 5. Mean heading dates of the $F_1$ and $F_2$ generations were earlier than those of mean mid-parent. Mean heading date of the $F_1$ generation was earlier than the $F_2$ generation. Crosses involving early-heading varieties showed a greater $F_1, $ mid-parent difference than crosses involving late-heading varieties. 6. Heading date was controlled by a partial dominance effect. Nine varieties excluding Mokpo # 42 showed allelic gene action. Ehime # 1, Shikoku # 42, Kagawa # 1 and Mokpo # 42 were recessive to the other tested varieties. 7. The $F_2$ segregations of the 45 crosses for days to heading showed that 33 cosses were of such complexity that they could not be explained by simple genetic inheritance. One cross showed a 3 : 1 ratio where earliness was dominant. Another cross showed a 3 : 1 ratio where lateness was dominant. Four other crosses showed a 9 : 7 ratio for earliness while six crosses showed a 9 : 7 ratio for lateness. 8. Many transgressive segregants for earliness were found in the following crosses; Eijo hadaka x Baegdong, Ehime # 1 x Seto hadaka, Yamate had aka x Kagawa # 1, Kagawa # 1 x Sato hadaka, Shikoku # 42 x Kagawa # 1, Ehime # 1 x Kagawa # 1, Ehime # 1 x Shikoku # 42, Ehime # 1 x Eijo hadaka. 9. Mean culm length of the F, and F. generations were usually taller than the mid-parent where tall parent were used. These trends were high in the short varieties, but low in the tall varieties. 10. Culm length was controlled by partial dominace which was gonverned by allelic gene(s). Culm length showed a high degree of control by additive genes. Mokpo # 42 was recessive while Baegdong was dominant. 11. The F_2 frequency for culm length was in large part normally distributed around the midparent value. However, some combinations showed transgressive segregation for either tall or short culm length. From combinations between medium tall varieties, Ehime # 1, Shikoku # 42, Eijo hadaka and Seto hadaka, many short segregants could be found. 12. Mean grain yields per plant of the F_1 and F_2 generations were 6% and 5% higher than those of mid-parents, respectively. The varieties with high yields per plant showed a low rate of yield increase in their F_1's and F_2's while the varieties with low yields per plant showed a high rate of yield increase in their F_1's and F_1's. 13. Grain yields per plant showed over-dominnee effects, governed by non-allelic genes. Mokpo # 42 showed recessive genetic control of grain yield per plant. It remains difficult to clarify the inheritance of grain yields per plant from these data.

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Problems in the Korean National Family Planning Program (한국가족계획사업(韓國家族計劃事業)의 문제점(問題點))

  • Hong, Jong-Kwan
    • Clinical and Experimental Reproductive Medicine
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    • v.2 no.2
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    • pp.27-36
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    • 1975
  • The success of the family planning program in Korea is reflected in the decrease in the growth rate from 3.0% in 1962 to 2.0% in 1971, and in the decrease in the fertility rate from 43/1,000 in 1960 to 29/1,000 in 1970. However, it would be erroneous to attribute these reductions entirely to the family planning program. Other socio-economic factors, such as the increasing age at marriage and the increasing use of induced abortions, definitely had an impact on the lowered growth and fertility rate. Despite the relative success of the program to data in meeting its goals, there is no room for complacency. Meeting the goal of a further reduction in the population growth rate to 1.3% by 1981 is a much more difficult task than any one faced in the past. Not only must fertility be lowered further, but the size of the target population itself will expand tremendously in the late seventies; due to the post-war baby boom of the 1950's reaching reproductive ages. Furthermore, it is doubtful that the age at marriage will continue to rise as in the past or that the incidence of induced abortion will continue to increase. Consequently, future reductions in fertility will be more dependent on the performance of the national family planning program, with less assistance from these non-program factors. This paper will describe various approaches to help to the solution of these current problems. 1. PRACTICE RATE IN FAMILY PLANNING In 1973, the attitude (approval) and knowledge rates were quite high; 94% and 98% respectively. But a large gap exists between that and the actual practice rate, which is only 3695. Two factors must be considered in attempting to close the KAP-gap. The first is to change social norms, which still favor a larger family, increasing the practice rate cannot be done very quickly. The second point to consider is that the family planning program has not yet reached all the eligible women. A 1973 study determineded that a large portion, 3096 in fact, of all eligible women do not want more children, but are not practicing family planning. Thus, future efforts to help close the KAP-gap must focus attention and services on this important large group of potential acceptors. 2. CONTINUATION RATES Dissatisfaction with the loop and pill has resulted in high discontinuation rates. For example, a 1973 survey revealed that within the first six months initial loop acceptance. nearly 50% were dropouts, and that within the first four months of inital pill acceptance. nearly 50% were dropouts. These discontinuation rates have risen over the past few years. The high rate of discontinuance obviously decreases the contraceptive effectiveness. and has resulted in many unwanted births which is directly related to the increase of induced abortions. In the future, the family planning program must emphasize the improved quality of initial and follow-up services. rather than more quantity, in order to insure higher continuation rates and thus more effective contraceptive protection. 3. INDUCED ABORTION As noted earlier. the use of induced abortions has been increase yearly. For example, in 1960, the average number of abortions was 0.6 abortions per women in the 15-44 age range. By 1970. that had increased to 2 abortions per women. In 1966. 13% of all women between 15-44 had experienced at least one abortion. By 1971, that figure jumped to 28%. In 1973 alone, the total number of abortions was 400,000. Besides the ever incre.sing number of induced abortions, another change has that those who use abortions have shifted since 1965 to include- not. only the middle class, but also rural and low-income women. In the future. in response to the demand for abortion services among rural and low-income w~men, the government must provide and support abortion services for these women as a part of the national family planning program. 4. TARGET SYSTIi:M Since 1962, the nationwide target system has been used to set a target for each method, and the target number of acceptors is then apportioned out to various sub-areas according to the number of eligible couples in each area. Because these targets are set without consideration for demographic factors, particular tastes, prejudices, and previous patterns of acceptance in the area, a high discontinuation rate for all methods and a high wastage rate for the oral pill and condom results. In the future. to alleviate these problems of the methodbased target system. an alternative. such as the weighted-credit system, should be adopted on a nation wide basis. In this system. each contraceptive method is. assigned a specific number of points based upon the couple-years of protection (CYP) provided by the method. and no specific targets for each method are given. 5. INCREASE OF STERILIZA.TION TARGET Two special projects. the hospital-based family planning program and the armed forces program, has greatly contributed to the increasing acceptance in female and male sterilization respectively. From January-September 1974, 28,773 sterilizations were performed. During the same time in 1975, 46,894 were performed; a 63% increase. If this trend continues, by the end of 1975. approximately 70,000 sterilizations will have been performed. Sterilization is a much better method than both the loop and pill, in terms of more effective contraceptive protection and the almost zero dropout rate. In the future, the. family planning program should continue to stress the special programs which make more sterilizations possible. In particular, it should seek to add the laparoscope techniques to facilitate female sterilization acceptance rates. 6. INCREASE NUMBER OF PRIVATE ACCEPTORS Among the current family planning users, approximately 1/3 are in the private sector and thus do not- require government subsidy. The number of private acceptors increases with increasing urbanization and economic growth. To speed this process, the government initiated the special hospital based family planning program which is utilized mostly by the private sector. However, in the future, to further hasten the increase of private acceptors, the government should encourage doctors in private practice to provide family planning services, and provide the contraceptive supplies. This way, those do utilize the private medical system will also be able to receive family planning services and pay for it. Another means of increasing the number of private acceptors, IS to greatly expand the commercial outlets for pills and condoms beyond the existing service points of drugstores, hospitals, and health centers. 7. IE&C PROGRAM The current preferred family size is nearly twice as high as needed to achieve a stable poplation. Also, a strong boy preference hinders a small family size as nearly all couples fuel they must have at least one or more sons. The IE&C program must, in the future, strive to emphasize the values of the small family and equality of the sexes. A second problem for the IE&C program to work. with in the: future is the large group of people who approves family planning, want no more children, but do not practice. The IE&C program must work to motivate these people to accept family planning And finally, for those who already practice, an IE&C program in the future must stress continuation of use. The IE&C campaign, to insure highest effectiveness, should be based on a detailed factor analysis of contraceptive discontinuance. In conclusion, Korea faces a serious unfavorable sociodemographic situation- in the future unless the population growth rate can be curtailed. And in the future, the decrease in fertility will depend solely on the family planning program, as the effect of other socio-economic factors has already been maximumally felt. A second serious factor to consider is the increasing number of eligible women due to the 1950's baby boom. Thus, to meet these challenges, the program target must be increased and the program must improve the effectiveness of its current activities and develop new programs.

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The Standing Crops and Soil-borne Microfungal Flora of Phyllostachys reticulata in Korea (한국산(韓國産) 왕대나무의 현존량(現存量)과 토양(土壤) 미세균류상(微細菌類相))

  • Kim, Kwan-Soo
    • The Korean Journal of Mycology
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    • v.7 no.2
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    • pp.91-116
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    • 1979
  • This paper is to investigate the standing crops and microfungal flora in soil in Phyllostachys reticulata forests in both the Yesan area (A) and the Kwangsan area (B). The stand density of the bamboo revealed 17,250 shoots per ha in area A, and in area B 14,780 shoots which were 16.1% less in number than area A. In respect to the environmental factors between the two areas, the mean temperature during the growth period was $1.5{\sim}2^{\circ}C$ higher in area B than in area A, soil tempeature also was $1{\sim}2^{\circ}C$ higher in area B, and the total quantities of nitrogen, phosphoric acid and organic compounds contained in the soil of area B were also slightly higher than those of area A. In area B the quantities of dried leaf matter, humus, and vegetation in the bamboo forest were also larger than in area A. In addition, five more species of microfungi which playa role in the decomposition of the various organic materials in the bamboo forests were identified in area B: Mortierella elongata, Mucor circinelloides, Aspergillus japonicus, Penicillium waksmani and Trichoderma lignorum. The atmospheric temperature in the inner portions of the bamboo forests was lower than the outside temperature, but the humidity was higher. The rates of relative illuminance were measured in area A at 4.19%, and in area B at 2.7%. These values revealed that the photosynthetic acitivity in the lower part of the bamboo was lost but it was considered that lower illuminance increased the microfungal activities in the vicinity of the surface soil. Since the productive structure of the bamboo showed that the maximum amount of photosynthesis was located in the upper portion of the bamboo in area B, it was considered to be an effective structure in maintaining the high productivity of the bamboo. The allometric relation between $D^2H$ and dry weight of stems(Ws), branches(Wb) and leaves(Wl) of the bamboo in area A were appoximated by log Ws=0.5262 log $D^2H$+1.9546; log Wb=0.6288 log $D^2H$+1.5723; log Wl=0.5181 log $D^2H$+1.8732, and those of the bamboo in area B were approximated by log Ws=0.5433 log $D^2H$+1.8610; log Wb=0.1630 log $D^2H$+2.3475; log Wl=0.4509 log $D^2H$+2.0041. From the above, the standing crops in area A were measured thus: Ws was 1,128. 83kg; Wb, 689.05kg; Wl, 926.69kg and Wl, 2,744.57kg per 10a. In area B, Ws was 1,206. 66kg; Wb, 679.92kg; Wl, 1,112.51kg and Wt, 2.999kg per l0a. Significant differences from the result of t-test were for $D^2H$ Ws, Wl and Wt between areas A and B. But no significant difference was found for Wb. In order to record as completely as possible the microfungal flora of the areas, every possible means was tried, and 158 strains of fungi were isolated, and of these, the microfungi of 55 species were identified. The dominant species were Trichoderma viride, Penicillium janthinellum, P. commune, Aspergillus oryzae, A. niger, A. gigantus, A. fumigatus, Mortierella ramaniana, var. anguliFPora, Mucor hiemalis and Zygorhynchus moelleri. According to the above results, it was revealed that optimum soil, the increases of soil materials, more species of soil microfungi, and the atmospheric temperature during the growth period have made the bamboo flourish and bring more species and larger quantities of vegetation in the bamboo forests. The correlation between the standing crops and environmental factors in the bamboo forest is considered to be a complicated relationship of all the factors, but the stand density is thought to be the most important factor involved.

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Development of Tuna Purse Seine Fishery in Korea and the Countries Concerned (한국(韓國) 및 관련각국((關聯各國)의 다랑어 선망어업(旋網漁業) 발달과정(發達過程))

  • Hyun, Jong-Su;Lee, Byoung-Gee;Kim, Hyoung-Seok;Yae, Young-Hee
    • Journal of Fisheries and Marine Sciences Education
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    • v.4 no.1
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    • pp.30-46
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    • 1992
  • Korea's first exploratory tuna fishing was done with a used longliner in 1957. Then the commercial fishing has been made steady headway since the 1960's and grown up to one of major tuna fishing countries in 1970's. The tuna fishing aimed primarily at acquiring foreign currency, then tuna was exported directly from the overseas fishing base. Tuna, however, has been gradually favored by Koreans as high-proteined foods according to the growth of GNP since the 1970's. In 1980, the canned tuna began to be produced and sold at home. And so the demand of raw tuna for cannaries has steeply increased not only for home but also for abroad, and stimulated the development of tuna purse seine fishery. The author carried out a study on the development of tuna purse seine fishery in Korea and countries concerned-the United States and Japan-because it is recognized to be significant for the further development of this fishery. Just as purse seining was originated in the United States, so tuna purse seining was also pioneered by Californian fishermen in the west coastal waters of the United States (Eastern Pacific Ocean). They started to produce the canned tuna in the early 1900's, and the demand for raw tuna began to be increased rapidly. In those days, tuna was mostly caught by pole-and-line, but the catch amount was far away from the demand. To satisfy this demand, they began to try out fishing tuna by the use of purse seine which had been born in the eastern waters in the 1820's and applied to catch white fishes in the western waters of the United States in those days. Even though their trial was technically successful through severe trial and error, a new problem was raised on the management of tuna resource and the preservation of porpoise which was occassionally caught with tuna. Then the Inter-American Tropical Tuna Commission (IATTC) was established by countries neighboring to the United States in 1950 and they set up the Commission's Yellowfin Regulatory Area (CYRA) and regulated the annual quota for yellowfin. Then, American owners tried to send their seiners to the Western African waters to expand the fishing ground in 1967 and to the Centeral-Western Pacfic in 1974, and the fishing ground was widely expanded. The number of the United States' purse seiners amounted to about 150 in 1980, but the enthusiasm was gradually cooled thereafter and the number of seiner was decreased to 67 in 1986. The landing of tuna by purse seiners in the United States after 1980 maintains 200 thousands M/T or so with a little increase despite the decreasing of domestic seiners. This shows that the landing by foreign seiners are increasing, compared with the landing by domestic seiners are decreasing. In Japan, even though purse seining was introduced in 1880, they had fished tuna by longline and pole-and -line until the tuna purse seining was introduced from the United States again. In the 1960's, Japanese tuna seiners made the exploratory fishing in the South-western Pacific and West African waters with a limited success. In 1971, the government-funded research center "JARMRAC" conducted the exploratory fishing which extended to the Central American waters, the Asia-Pacific Region and the South-western Pacific. It had also much difficulties, till they improved the fishing gear adaptable to the new fishing condition in the South-western Pacific. Japanese government has begun to licence 32 single seiners and 7 group seiners since 1980 and their standard has lasted up to now. The catch in the Pacific Islands Region amounted to 160 thousands M/T in 1986. Korea's tuna purse seine fishery was originated in 1971 by Jedong Industrial Co., Ltd. with three used tuna purse seiners purchased from the United States, and they began to fish in the Eastern Pacific, but failed owing to the superannuation of vessel and the infancy of fishing technique. The second challenge was done by Dongwon Industrial Co., Ltd. in 1979, with one used seiner purchased from the United States, and started to fish in the Eastern Pacific. Even though the first trial was almost unsuccessful but they could obtain the noticeable success by removing the vessel to the South-western Pacific in 1980. This success stimulated the Korean entherprisers to take part in this fishery, and the number of Korean tuna purse seiners has been increased rapidly in accordance with the increased demand for raw tuna. The number of vessels actually at work amounted to 36 in 1990 and they operate in the South-western Pacific. The annual catch of tuna by purse seiners amounted to 170 thousands M/T in 1990 and ranked to one of the major tuna purse seining countries in the world.

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A Study on Jurisdiction under the International Aviation Terrorism Conventions (국제항공테러협약의 관할권 연구)

  • Kim, Han-Taek
    • The Korean Journal of Air & Space Law and Policy
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    • v.24 no.1
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    • pp.59-89
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    • 2009
  • The objectives of the 1963 Tokyo Convention cover a variety of subjects, with the intention of providing safety in aircraft, protection of life and property on board, and promoting the security of civil aviation. These objectives will be treated as follows: first, the unification of rules on jurisdiction; second, the question of filling the gap in jurisdiction; third, the scheme of maintaining law and order on board aircraft; fourth, the protection of persons acting in accordance with the Convention; fifth, the protection of the interests of disembarked persons; sixth, the question of hijacking of aircraft; and finally some general remarks on the objectives of the Convention. The Tokyo Convention mainly deals with general crimes such as murder, violence, robbery on board aircraft rather than aviation terrorism. The Article 11 of the Convention deals with hijacking in a simple way. As far as aviation terrorism is concerned 1970 Hague Convention and 1971 Montreal Convention cover the hijacking and sabotage respectively. The Problem of national jurisdiction over the offence and the offender was as tangled at the Hague and Montreal Convention, as under the Tokyo Convention. Under the Tokyo Convention the prime base of jurisdiction is the law of the flag (Article 3), but concurrent jurisdiction is also allowed on grounds of: territorial principle, active nationality and passive personality principle, security of the state, breach of flight rules, and exercise of jurisdiction necessary for the performance of obligations under multilateral agreements (Article 4). No Criminal jurisdiction exercised in accordance with national law is excluded [Article 3(2)]. However, Article 4 of the Hague Convention(hereafter Hague Article 4) and Article 5 of the Montreal Convention(hereafter Montreal Article 5), dealing with jurisdiction have moved a step further, inasmuch as the opening part of both paragraphs 1 and 2 of the Hague Article 4 and the Montreal Article 5 impose an obligation on all contracting states to take measures to establish jurisdiction over the offence (i.e., to ensure that their law is such that their courts will have jurisdiction to try offender in all the circumstances covered by Hague Article 4 and Montreal Article 5). The state of registration and the state where the aircraft lands with the hijacker still on board will have the most interest, and would be in the best position to prosecute him; the paragraphs 1(a) and (b) of the Hague Article 4 and paragraphs 1(b) and (c) of the Montreal Article 5 deal with it, respectively. However, paragraph 1(b) of the Hague Article 4 and paragraph 1(c) of the Montreal Article 5 do not specify if the aircraft is still under the control of the hijacker or if the hijacker has been overpowered by the aircraft commander, or if the offence has at all occurred in the airspace of the state of landing. The language of the paragraph would probably cover all these cases. The weaknesses of Hague Article 4 and Montreal Article 5 are however, patent. The Jurisdictions of the state of registration, the state of landing, the state of the lessee and the state where the offender is present, are concurrent. No priorities have been fixed despite a proposal to this effect in the Legal Committee and the Diplomatic Conference, and despite the fact that it was pointed out that the difficulty in accepting the Tokyo Convention has been the question of multiple jurisdiction, for the reason that it would be too difficult to determine the priorities. Disputes over the exercise of jurisdiction can be endemic, more so when Article 8(4) of the Hague Convention and the Montreal Convention give every state mentioned in Hague Article 4(1) and Montreal Article 5(1) the right to seek extradition of the offender. A solution to the problem should not have been given up only because it was difficult. Hague Article 4(3) and Montreal Article 5(3) provide that they do not exclude any criminal jurisdiction exercised in accordance with national law. Thus the provisions of the two Conventions create additional obligations on the state, and do not exclude those already existing under national laws. Although the two Conventions do not require a state to establish jurisdiction over, for example, hijacking or sabotage committed by its own nationals in a foreign aircraft anywhere in the world, they do not preclude any contracting state from doing so. However, it has be noted that any jurisdiction established merely under the national law would not make the offence an extraditable one under Article 8 of the Hague and Montreal Convention. As far as international aviation terrorism is concerned 1988 Montreal Protocol and 1991 Convention on Marking of Plastic Explosives for the Purpose of Detention are added. The former deals with airport terrorism and the latter plastic explosives. Compared to the other International Terrorism Conventions, the International Aviation Terrorism Conventions do not have clauses of the passive personality principle. If the International Aviation Terrorism Conventions need to be revised in the future, those clauses containing the passive personality principle have to be inserted for the suppression of the international aviation terrorism more effectively. Article 3 of the 1973 Convention on the Prevention and Punishment of Crimes Against Internationally Protected Persons, Including Diplomatic Agents, Article 5 of the 1979 International Convention against the Taking of Hostages and Article 6 of the 1988 Convention for the Suppression of Unlawful Acts Against the Safety of Maritime Navigation would be models that the revised International Aviation Terrorism Conventions could follow in the future.

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Spatial Distribution of Aging District in Taejeon Metropolitan City (대전광역시 노령화 지구의 공간적 분포 패턴)

  • Jeong, Hwan-Yeong;Ko, Sang-Im
    • Journal of the Korean association of regional geographers
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    • v.6 no.2
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    • pp.1-19
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    • 2000
  • This study is to investigate and analyze regional patterns of aging in Taejeon Metropolitan city-the overpopulated area of Choong-Cheong Province-by cohort analysis method. According to the population structure transition caused by rapid social and economic changes, Korea has made a rapid progress in population aging since 1970. This trend is so rapid that we should prepare for and cope with aging society. It is not only slow to cope with it in our society, but also there are few studies on population aging of the geographical field in Korea. The data of this study are the reports of Population and Housing Censuses in 1975 and 1985 and General Population and Housing Censuses with 10% sample survey in 1995 taken by National Statistical Office. The research method is to sample as the aging district the area with high aged population rate where the populations over 60 reside among total population during the years of 1975, 1985, 1995 and to sample the special districts of decreasing population where the population decreases very much and the special districts of increasing population in which the population increases greatly, presuming that the reason why aged population rate increases is that non-elderly population high in mobility moves out. It is then verified and ascertained whether it is true or not with cohort analysis method by age. Finally regional patterns in the city are found through the classification and modeling by type based on the aging district, the special districts of decreasing population, and the special districts of increasing population. The characteristics of the regional patterns show that there is social population transition and that non-elderly population moves out. The aging district with the high aged population rate is divided into high-level keeping-up type, relative falling type below the average of Taejeon city in aging progress, and relative rising type above the average of the city. This district can be found at both the central area of the city and the suburbs because Taejeon city has the characteristic of over-bounded city. But it cannot be found at the new built-up area with the in-migration of large population. The special districts of decreasing population where the population continues to decrease can be said to be the population doughnuts found at the CBD and its neighboring inner area. On the other hand, the special districts of increasing population where the population continues to increase are located at the new built-up area of the northern part in Taejeon city. The special districts of decreasing population are overlapping with the aging district and higher in aged population rate by the out-migration of non-elderly population. The special districts of increasing population are not overlapping with the aging district and lower in aged population rate by the in-migration of non-elderly population. To clarify the distribution map of the aging district, the special districts of decreasing and increasing population and the aging district are divided into four groups such as the special districts of decreasing population group-the same one as the aging district, the special districts of decreasing population group, the special districts of increasing population group, and the other district. With the cohort analysis method by age used to investigate the definite increase and decrease of aging population through population transition of each group, it is found that the progress of population aging is closely related to the social population fluctuation, especially that aged population rate is higher with the out-migration of non-elderly population. This is to explain each model of CBD, inner area, and the suburbs after modeling the aging district, the special districts of decreasing population, and the special districts of increasing population in Taejeon city. On the assumption that the city area is a concentric circle, it is possible to divide it into three areas such as CBD(A), the inner area(B), and the suburbs(C). The special districts of increasing and decreasing population in the city are divided into three districts-the special districts of decreasing population(a), the special districts of increasing population(b), and the others(c). The aging district of this city is divided into the aging district($\alpha$) and the others($\beta$). And then modeling these districts, it is probable to find regional patterns in the city. $Aa{\alpha}$ and $Ac{\beta}$ patterns are found in the CBD, in which $Aa{\alpha}$ is the special district of decreasing population and is higher in aged population rate because of aged population low in mobility staying behind and out-migration of non-elderly population. $Ba{\alpha}$, $Ba{\beta}$, $Bb{\beta}$, and $Bc{\beta}$ patterns are found in the inner area, in which neighboring area $Ba{\alpha}$ pattern is located. $Bb{\beta}$ pattern is located at the new developing area of newly built apartment complex. $Cb{\beta}$, $Cc{\alpha}$, and $Cc{\beta}$ patterns are found in the suburbs, among which $Cc{\alpha}$ pattern is highest in population aging. It is likely that the $Cc{\beta}$ under housing land readjustment on a large scale will be the $Cb{\beta}$ pattern. As analyzed above, marriage and out-migration of new family, non-elderly population, with house purchase are main factors in accelerating population aging in the central area of the city. Population aging is responsible for the great increase of aged population with longer life expectancy by the low death rate, the out-migration of non-elderly population, and the age group of new aged population in the suburbs. It is necessary to investigate and analyze the regional patterns of population aging at the time when population problems caused by aging as well as longer life expectancy are now on the increase. I hope that this will help the future study on population aging of the geographical field in Korea. As in the future population aging will be a major problem in our society, local autonomy should make a plan for the problem to the extent that population aging progresses by regional groups and inevitably prepare for it.

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Studies on Increasing the Efficiency of Nitrogen Nutrition (질소영양(窒素營養)의 효율증진(效率增進)에 관(關)한 연구(硏究))

  • Kwack, Pan-Ju
    • Applied Biological Chemistry
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    • v.11
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    • pp.151-166
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    • 1969
  • I. Fffects of nitrogen supplying level and culture condition on the top growth aod tubers formation of Ipomoea Batatas. 1) The low level nitrogen (A plot) 3 Milliequivalent per liter of nutrient solution stimulated tuber formation while the high level nitrogen ($B_1\;and\;B_2$ plot) of 10 milliequivalent per liter failed to form tuber though fibrous roots were seen much activated. The suppressive effect of nitrogen on tuber formation in presumed to result from the direct suppressive effect of nitrogen or a certain biocatalystic effect rather than from any indirect effect through the stimulation to growth of tops or the competition with carbohydrates. 2) The addition of milligram urea to nutrient solution stimulated the growth and increased fresh weight and dry weight of the aerial part while suppressed, a little, plant length. 3) The water culture method, which this experiment newly adopted, stimulated plant growth more than the gravel Culture method. And the treatment of low level nitrogen (A plot) in this water culture also saw a considerable degree of tuber formation, as in the case of gravel culture. 4) The foliar application of growth retardant B-nine suppressed the plant length only, with no other recognizable effect. II. Fffects of urea supplying level on the growth of IPOMOEA BATATAS. 1) The higher level of urea which was absorbed tby roots through nutrient solution suppressed top growth, such as plant length, number of leaves and fresh weight. And this can be attributed to the direct absorption of urea which was not ammonificated. 2) Although the higher level of nitrate nitrogen (B plot) made no tuber formation in previous experiment (Report-1), the higher level of urea nitrogen (A plot) made tuber formation possible in this experiment. The ratio of tuber to top was, however, less in higher level of urea than in lower level of urea, and the suppressing effect was larger on tuber than on top. 3) The foliar application of urea stimulated top growth while the higher level of urea absorbed by roots suppressed it, though the amounts of urea supplied in two experiments were same. Ratio of top to roots was larger in foliar application of urea (C plot) and less in root absorption of urea both of higher (B plot) and lower urea levels (A plot). III. Fffects of growth retardant etc. on the growth of IPOMOEA BATATAS in relation to urea application. 1) B-nine (N-dimethyl amino-succinamic acid) is recognized as a growth retardant, suppressed the plant length irrespective of urea levels. The treatment of gibberellin stimulated distinctly plant length, and the combined treatment of gibberellin and B-nine recovered completely the plant length which had been suppressed by B-nine. 2) B-nine increased fresh weight, especially, fresh weight of top both in lower and higher level of The degree of fresh weight increase varied according to concentrations of B-nine, of which the 0.15% of B-nine ($B_1$ plot) was the effective in higher level of urea. The effect of B-nine for increasing fresh weight was the largest in top next in tuber, and the least in fibrous roots. The ratio of fibrous roots to top was always decreased by B-nine application, which the ratio of tuber to top was contrary increased by B-nine in higher level of urea though decreased in lower level of urea. 3) Gibberellin treatment also increased fresh weight but the combined treatment ($B_3$+GA plot) of gibberellin and B-nine was even more effective than any of single treatments. Gibberellin and B-nine proved to be synergistic with fresh weight while reverse with plant length. 4) Considerable influences were abserved mainly in the length of plants and their fresh weight after B-nine treatment. So that B-nine may be reguraded as a metabolic controller rather than as an antimetabolite. 5) The surpressed growth of plants cause by higher level of urea was normalized by B-nine treatment. This fact suggested a further study on the applicability for practical use.

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Studies on the Drying Mechanism of Stratified Soil-Comparison between Bare Surface and Grass plot- (성층토양의 건조기구에 관한 연구)

  • 김철기
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.15 no.1
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    • pp.2913-2924
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    • 1973
  • This study was to investigate the drying mechanism of stratified soil by investigating 'effects of the upper soil on moisture loss of the lower soil and vice versa' and at the same time by examining how the drying progressed in the stratified soils with bare surface and with vegetated surface respectively. There were six plots of the stratified soils with bare surface($A_1- A_6$ plot) and the same other six plots($B_1- B_5$ plot), with vegetated surface(white clover). These six plots were made by permutating two kinds of soils from three kinds of soils; clay loam(CL). Sandy loam(SL). Sand(s). Each layer was leveled by saturating sufficient water. Depth of each plot was 40cm by making each layer 20cm deep and its area. $90{\times}90(cm^2)$. The cell was put at the point of the central and mid-depth of the each layer in the each plot in order to measure the soil moisture by using OHMMETER. soil moisture tester, and movement of soil water from out sides was cut off by putting the vinyl on the four sides. The results obtained were as follow; 1. Drying progressed from the surface layer to the lower layer regardless of plots. There was a tendency thet drying of the upper soil was faster than that of the lower soil and drying of the plot with vegetated surface was also faster than that of the plot with bare surface. 2. Soil moisture was recovered at approximately the field capacity or moisture equivalent by infiltration in the course of drying, when there was a rainfall. 3. Effects of soil texture of the lower soil on dryness of the upper soil in the stratified soil were explained as follows; a) When the lower soil was S and the upper, CL or SL, dryness of the upper soils overlying the lower soil of S was much faster than that overlying the lower soil of SL or CL, because sandy soil, having the small field capacity value and playing a part of the layer cutting off to some extent capillary water supply. Drying of SL was remarkably faster than that of CL in the upper soil. b) When the lower soil was SL and the upper S or CL, drying of the upper soil was the slowest because of the lower SL, having a comparatively large field capacity value. Drying of CL tended to be faster than that of S in the upper soil. c) When the lower soil was CL and the upper S or SL, drying of the upper soil was relatively fast because of the lower CL, having the largest field capacity value but the slowest capillary conductivity. Drying of SL tended to be faster than that of S in the upper soil. 4. According to a change in soil moisture content of the upper soil and the lower soil during a day there was a tendency that soil moisture contents of CL and SL in the upper soil were decreased to its minimum value but that of S increased to its maximum value, during 3 hours between 12.00 and 15.00. There was another tendency that soil moisture contents of CL, SL and S in the lower soil were all slightly decreased by temperature rising and those in a cloudy day were smaller than those in a clear day. 5. The ratio of the accumulated soil moisture consumption to the accumulated guage evaporation in the plot with vegetated surface was generally larger than that in the plot with bare surface. The ratio tended to decrease in the course of time, and also there was a tendency that it mainly depended on the texture of the upper soil at the first period and the texture of the lower soil at the last period. 6. A change in the ratio of the accumulated soil moisture consumption was larger in the lower soil of SL than in the lower soil of S. when the upper soil was CL and the lower, SL and S. The ratio showed the biggest figure among any other plots, and the ratio in the lower soil plot of CL indicated sligtly bigger than that in the lower soil plot of S, when the upper soil was SL and the lower, CL and S. The ratio showed less figure than that of two cases above mentioned, when the upper soil was S and the lower CL and SL and that in the lower soil plot of CL indicated a less ratio than that in the lower soil plot of SL. As a result of this experiments, the various soil layers wero arranged in the following order with regard to the ratio of the accumulated soil moisture consumption: SL/CL>SL/S>CL/SL>CL/S$\fallingdotseq$S/SL>S/CL.

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Clustering Method based on Genre Interest for Cold-Start Problem in Movie Recommendation (영화 추천 시스템의 초기 사용자 문제를 위한 장르 선호 기반의 클러스터링 기법)

  • You, Tithrottanak;Rosli, Ahmad Nurzid;Ha, Inay;Jo, Geun-Sik
    • Journal of Intelligence and Information Systems
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    • v.19 no.1
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    • pp.57-77
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    • 2013
  • Social media has become one of the most popular media in web and mobile application. In 2011, social networks and blogs are still the top destination of online users, according to a study from Nielsen Company. In their studies, nearly 4 in 5active users visit social network and blog. Social Networks and Blogs sites rule Americans' Internet time, accounting to 23 percent of time spent online. Facebook is the main social network that the U.S internet users spend time more than the other social network services such as Yahoo, Google, AOL Media Network, Twitter, Linked In and so on. In recent trend, most of the companies promote their products in the Facebook by creating the "Facebook Page" that refers to specific product. The "Like" option allows user to subscribed and received updates their interested on from the page. The film makers which produce a lot of films around the world also take part to market and promote their films by exploiting the advantages of using the "Facebook Page". In addition, a great number of streaming service providers allows users to subscribe their service to watch and enjoy movies and TV program. They can instantly watch movies and TV program over the internet to PCs, Macs and TVs. Netflix alone as the world's leading subscription service have more than 30 million streaming members in the United States, Latin America, the United Kingdom and the Nordics. As the matter of facts, a million of movies and TV program with different of genres are offered to the subscriber. In contrast, users need spend a lot time to find the right movies which are related to their interest genre. Recent years there are many researchers who have been propose a method to improve prediction the rating or preference that would give the most related items such as books, music or movies to the garget user or the group of users that have the same interest in the particular items. One of the most popular methods to build recommendation system is traditional Collaborative Filtering (CF). The method compute the similarity of the target user and other users, which then are cluster in the same interest on items according which items that users have been rated. The method then predicts other items from the same group of users to recommend to a group of users. Moreover, There are many items that need to study for suggesting to users such as books, music, movies, news, videos and so on. However, in this paper we only focus on movie as item to recommend to users. In addition, there are many challenges for CF task. Firstly, the "sparsity problem"; it occurs when user information preference is not enough. The recommendation accuracies result is lower compared to the neighbor who composed with a large amount of ratings. The second problem is "cold-start problem"; it occurs whenever new users or items are added into the system, which each has norating or a few rating. For instance, no personalized predictions can be made for a new user without any ratings on the record. In this research we propose a clustering method according to the users' genre interest extracted from social network service (SNS) and user's movies rating information system to solve the "cold-start problem." Our proposed method will clusters the target user together with the other users by combining the user genre interest and the rating information. It is important to realize a huge amount of interesting and useful user's information from Facebook Graph, we can extract information from the "Facebook Page" which "Like" by them. Moreover, we use the Internet Movie Database(IMDb) as the main dataset. The IMDbis online databases that consist of a large amount of information related to movies, TV programs and including actors. This dataset not only used to provide movie information in our Movie Rating Systems, but also as resources to provide movie genre information which extracted from the "Facebook Page". Formerly, the user must login with their Facebook account to login to the Movie Rating System, at the same time our system will collect the genre interest from the "Facebook Page". We conduct many experiments with other methods to see how our method performs and we also compare to the other methods. First, we compared our proposed method in the case of the normal recommendation to see how our system improves the recommendation result. Then we experiment method in case of cold-start problem. Our experiment show that our method is outperform than the other methods. In these two cases of our experimentation, we see that our proposed method produces better result in case both cases.

The Aspects of Change of Sijo (시조의 변이 양상)

  • Kang Myeoung-Hye
    • Sijohaknonchong
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    • v.24
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    • pp.5-46
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    • 2006
  • Korean verse has flexibly changed its form and contents according to the historical background of the times. This fact arouses reader sympathy because it has reflected ideas, historical aspects and realities of the times. However, korean verse has kept its own characteristics in some ways, allowing it to exist today. It holds its form as 3 verses of three by three or four meter and three letters of the last of three verses. It makes every different version which has specific aspects of each times in the same 'sijo' area. 'Sijo' in Korean poems, is the first form that has been changed from formal to private functionally. As a result of that common verses in the Goryeo to Joseon eras were going with the stream of the times. Verse was the plate for justice so that there was no double meaning, symbols, or technical sentences. It had to show the idea of Myungchundo Jwonginryun. The theme was commonly fitted within certain areas. such as blessings, fidelity, devotion, etc. Around the end of the Joseon era, there was activation of private verses - a form of sijo with no restrictions on the length of the first two verses. Some ideas had been changed because Sarimpa gained power, domestic conflict, and the introduction of practical science. These things had an effect on the form of Sijo. After all, it shows the ideas of collapsing feudalism, resistance of confucian ideas, equality of the sexes, and opposition to the group who rule the government. Thus Sasul Sijo seems to have the tendency of resistance to reality. It was a specialty of realism poetry It explained our life in detail and reflected real life by being an intermediary of realism. This met and represented the demand of a reader's expectations. After 1905, there was new form of sijo that is very different, in form and content, from the previous versions. It was even different in areas of what people accepted. They started to think sijo was not the form of lyrical verse that is once was. It became a 'record of reading'. The form changed to 'hung or huhung' that satirized the times and the ending of a word in the last verse. Although this form could deliver the tension in statement, it was too iu from the original form. Therefore, it didn't last long, and its position got smaller because of the free verse that had western influence and was emerging in the times. In the middle of 1920, there was a movement of Sijo revival. It was lead by Choinamsun. He wrote poems and Sijo which were effected by western ideas in his early works. Although he worked with that, he took the lead in the movement of Sijo revival. He published the collection of Sijo $\ulcorner$Baekpalbunnwoi$\lrcorner$ that has one major theme-patriotic sentiment. He thought an ancient poem was a part of racial characteristics so that he expressed the main theme which represented the times and situations of his era. Modern Sijo is difficult. Sijo has to have modern and Korean verse characteristics at the same time. If it considers a modern aspect too much, it could not be distinguished from sijo and free verse. If it overly leans toward Sijo. it would seem to be too conservative which it then could be said to have no real charm of a poem. In spite of these problems, it is written constantly, because it has its own specialty. It has been focused on some works because they reflect awareness of modern times, the democratic idea, and realism. Overall, the authors of Modern Sijo express various themes by using different forms. The more what we can guess in this work, Sijo will exist permanently because of its flexibility. Furthermore, one special characteristic-flexibility of the korean verse will make it last forever and it will be a genre in Korean poetry.

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