• Title/Summary/Keyword: Climatic Change

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A Study on Principle of Kigong mentioned in the lecture on Truth of ${\ll}$Samilshingo${\gg}$(三一神誥) and its Interrelationship with Oriental Medicine (${\ll}$삼일신고(三一神誥).진리훈(眞理訓)${\gg}$에 나타난 氣功原理(氣功原理) 및 한의학(韓醫學)과 의 상관성(相關性)에 관(關)한 연구(硏究))

  • Ban Chang-Youl;Jee Seon-Young;Gang Go-Sin
    • Journal of Korean Medical Ki-Gong Academy
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    • v.4 no.2
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    • pp.153-186
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    • 2000
  • Jigam(止感), Josik(調息), Kumchock(禁觸), from the lecture on Truth of ${\ll}Samilshingo{\gg}$(三一神誥) treat three elements of Kigong, regulation of mental activties, regulation of breathing and adjustment of posture and there are some similar mentions with the view of human body based on oriental medicine like those Samjin(三眞), Sammang(三妄), Samdo(三途) and Sippalkyoung(十八境) ect. Thus as a result of comparison and observation about the interrelationships between principle of Kigong in the lecture on Truth of ${\ll}Samilshingo{\gg}$(三一神誥) and oriental medicine. I have conclusion as follows. 1. According to the lecture on Truth, the components of human body are the one and only Samjin(三眞), Sammang(三妄) and Samdo(三途) resulted from facing Samjin(三眞) to Sammang(三妄) and Sippalkyoung(十八境). This fact presents the principle of human change. 2. the principle of Kigong mentioned in the lecture on Truth shows the original Ilshin(一神) on the basis of Samjin(三眞), Sammang(三妄), Samdo(三途) and Sippalkyoung(十八境). This makes common, unity and sound Sim(心), Ki(氣) and Shin(身), Sammang(三妄) through Jigam(止感), Josik(調息) and Kumchock(禁觸), be versed, intellected and guaranteed Sung(性), Myoung(命) and Jung(精), Samjin(三眞) and emit Kyun(見), Mun(聞), Ji(知) and haeng(行), Sadaeshingi(四大神機) and finally all these are harmonized into Duk(德), Hye(慧) and Ryuk(力), Samdae(三大) which is the entity of God. 3. Samsipyookjongmyowhasang(三十六種妙化相) is an ascetic practice done after a chulin(哲人) deduce Ji(止), Jo(調) and Kum(禁), Sambup(三法) on the basis of the lecture on Truth. So I suppose it correlates nature's six elements. Kong(空)(Chun(天)). Yol(熱)(Wha(火)). Jin(震(Jeon(電)), Seup(濕)(Shoo(水)), Han(寒)(Poong(風)) and Ko(固)(Ji(地)), human's Samjin(三眞), Sung(性), Myoung(命) and Jung(精) and Sammang(三妄), Sim(心), Ki(氣) and Shin(身) and makes clear the principle of discipline. 4. In comparison with Samjin(三眞) and Sammang(三妄) says from the lecture on Truth and the Three Essential Elements of the body construction(三寶) from oriental medicine, Samjin(三眞) and Sammang(三妄) as factors of human body in the concept of practical knowledge. That is the one and only Samjin(三眞) in terms of the Three Essential Elements of the body construction(三寶) is considered a structural principle for every single person and Sammang(三妄) is considered a functional form for each individual. And it can be Sung(性)+Sim(心)=Spirit(神), Myoung(命)+Ki(氣)=Vital Force(氣) and Jung(精)+Shin(身)=True Essence(精). 5. In comparison with Sippalkyoung(十八境) of Samdo(三途) from the lecture on Truth and three medical causes of disease, Gamdoyookkyoung(感途六境) is similar with endopathic cause caused by Naesangchiljung(內傷七情), Sikdoyukkyoung(息途六境) is similar with exopathic cause by six climatic conditions in excess as pathogenic factors(六淫) and Yoegi(?氣) and Chokdoyukkyoung(觸途六境) is similar with non-endo-exopathogenic causes by diet imbalance, fatigue, intemperance in sexual life and trauma etc. 6. In the lecture on Truth, the Chulin(哲人) who discipline Sambup(三法), Sangchul(上哲), Choongchul(中哲) and Hachul(下哲) can be compared with Kigong expert(health preserving expert) such as the Spiritual Men(眞人), the Sapients(至人), the Sages(聖人) and the Men of Exellent Virtue(寶人) in the Sang Gu Tian Zhen Lun of the Huang Ti Nei Ching Su Wen(素問 上古天眞論) and then Sangchul(上哲) is the Spiritual Men(眞人), Choongchul(中哲) is the Sapients(至人) and Hachul(下哲) is the Sages(聖人) while the men of Exellent Virtue(賢人) is inferior to Chulin(哲人) when he goes to extremes.

Prediction of Radish Growth as Affected by Nitrogen Fertilization for Spring Production (무의 질소 시비량에 따른 생육량 추정 모델식 개발)

  • Lee, Sang Gyu;Yeo, Kyung-Hwan;Jang, Yoon Ah;Lee, Jun Gu;Nam, Chun Woo;Lee, Hee Ju;Choi, Chang Sun;Um, Young Chul
    • Horticultural Science & Technology
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    • v.31 no.5
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    • pp.531-537
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    • 2013
  • The average annual and winter ambient air temperatures in Korea have risen by 0.7 and $1.4^{\circ}C$, respectively, during the last 30 years. Radish (Raphanus sativus), one of the most important cool season crops, may well be used as a model to study the influence of climatic change on plant growth, because it is more adversely affected by elevated temperatures than warm season crops. This study examined the influence of transplanting time, nitrogen fertilizer level, and climate parameters, including air temperature and growing degree days (GDD), on the performance of a radish cultivar 'Mansahyungtong' to estimate crop growth during the spring growing season. The radish seeds were sown from April 24 to May 22, 2012, at internals of 14 days and cultivated with 3 levels of nitrogen fertilization. The data from plants sown on April 24 and May 8, 2012 were used for the prediction of plant growth as affected by planting date and nitrogen fertilization for spring production. In our study, plant fresh weight was higher when the radish seeds were sown on $24^{th}$ of April than on $8^{th}$ and $22^{nd}$ of May. The growth model was described as a logarithmic function using GDD according to the nitrogen fertilization levels: for 0.5N, root dry matter = 84.66/(1+exp (-(GDD - 790.7)/122.3)) ($r^2$ = 0.92), for 1.0N, root dry matter = 100.6/(1 + exp (-(GDD - 824.8)/112.8)) ($r^2$ = 0.92), and for 2.0N, root dry matter = 117.7/(1+exp (-(GDD - 877.7)/148.5)) ($r^2$ = 0.94). Although the model slightly tended to overestimate the dry mass per plant, the estimated and observed root dry matter and top dry matter data showed a reasonable good fit with 1.12 ($R^2$ = 0.979) and 1.05 ($R^2$ = 0.991), respectively. Results of this study suggest that the GDD values can be used as a good indicator in predicting the root growth of radish.

Estimation of sediment deposition rate in collapsed reservoirs(wetlands) using empirical formulas and multiple regression models (경험공식 및 다중회귀모형을 이용한 붕괴 저수지(습지) 비퇴사량 추정)

  • Kim, Donghyun;Lee, Haneul;Bae, Younghye;Joo, Hongjun;Kim, Deokhwan;Kim, Hung Soo
    • Journal of Wetlands Research
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    • v.23 no.4
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    • pp.287-295
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    • 2021
  • As facilities such as dam reservoir wetlands and agricultural irrigation reservoir wetlands are built, sedimentation occurs over time through erosion, sedimentation transport, and sediment deposition. Sedimentation issues are very important for the maintenance of reservoir wetlands because long-term sedimentation of sediments affects flood and drought control functions. However, research on resignation has been estimated mainly by empirical formulas due to the lack of available data. The purpose of this study was to calculate and compare the sediment deposition rate by developing a multiple regression model along with actual data and empirical formulas. In addition, it was attempted to identify potential causes of collapse by applying it to 64 reservoir wetlands that suffered flood damage due to the long rainy season in 2020 due to reservoir wetland sedimentation and aging. For the target reservoir, 10 locations including the GaGog reservoir located in Miryang city, Gyeongsangnam province in South Korea, where there is actual survey information, were selected. A multiple regression model was developed in consideration of physical and climatic characteristics, and a total of four empirical formulas and sediment deposition rate were calculated. Using this, the error of the sediment deposition rate was compared. As a result of calculating the sediment deposition rate using the multiple regression model, the error was the lowest from 0.21(m3km2/yr) to 2.13(m3km2/yr). Therefore, based on the sediment deposition rate estimated by the multi-regression model, the change in the available capacity of reservoir wetlands was analyzed, and the effective storage capacity was found to have decreased from 0.21(%) to 16.56(%). In addition, the sediment deposition rate of the reservoir where the overflow damage occurred was relatively higher than that of the reservoir where the piping damage occurred. In other words, accumulating sediment deposition rate at the bottom of the reservoir would result in a lack of acceptable effective water capacity and reduced reservoir flood and drought control capabilities, resulting in reservoir collapse damage.

A Study on the Construction Characteristics of Folk Houses Designated as Cultural Heritage in Jeolla-do Province (전라도 지역 문화재 지정 민가정원의 현황 및 조영특성)

  • Jin, Min-Ryeong;Jeong, Myeong-Seok;Sim, Ji-Yeon;Lee, Hye-Suk;Lee, Kyung-Mi;Jin, Hye-Yeong
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.38 no.4
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    • pp.25-38
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    • 2020
  • For the purpose of recording Folk House Garden, this study was to review the historical value, location, space composition, Placememnt of the Building, garden composition, and management status of Folk House Garden designated as a cultural asset in Jeolla-do and to promote continuous maintenance and preservation in the future and enhance its value. The results of the study are as follows. First, most of them have been influenced by the trend of the times, such as the creation of a modern private garden and the spread of agricultural and commercial development through the garden components influenced by the royal, Japanese, and Western styles. Second, there are differences in the spatial composition of private households and the way they handle sponsorship, depending on the geographical location. When the geographical features were divided into flat and sloping areas, private houses located on flat land were divided into walls, walls were placed around the support area, and flower systems and stone blocks were created. The private houses located on the slope were divided into two to three tiers of space, and the wooden plant, flower bed, and stone bed were naturally connected to the background forest without creating a wall at the rear hill. Third, the size of the house and the elements of the garden have been partially destroyed, damaged, and changed, and if there is a lack of records of the change process, there is a limit to the drawing floor plan. There were many buildings and garden components that were lost or damaged due to changes in the trend and demand of the times, and some of them without records had to rely on the memory of owners and managers. Fourth, the species in Warm Temperate Zone, which reflects the climatic characteristics of Jeolla-do, was produced, and many of the exotic species, not traditional ones, were introduced. Fifth, fine-grained tree management standards are needed to prepare for changes in spatial function and plant species considering modern convenience.

Effects of Elevated Temperature after the Booting Stage on Physiological Characteristics and Grain Development in Wheat (밀에서 출수 후 잎의 생리적 특성 및 종실 생장에 대한 수잉기 이후 고온의 효과)

  • Song, Ki Eun;Choi, Jae Eun;Jung, Jae Gyeong;Ko, Jong Han;Lee, Kyung Do;Shim, Sang-In
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.66 no.4
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    • pp.307-317
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    • 2021
  • In recent years, global warming has led to frequent climate change-related problems, and elevated temperatures, among adverse climatic factors, represent a critical problem negatively affecting crop growth and yield. In this context, the present study examined the physiological traits of wheat plants grown under high temperatures. Specifically, the effects of elevated temperatures on seed development after heading were evaluated, and the vegetation indices of different organs were assessed using hyperspectral analysis. Among physiological traits, leaf greenness and OJIP parameters were higher in the high-temperature treatment than in the control treatment. Similarly, the leaf photosynthetic rate during seed development was higher in the high-temperature treatment than in the control treatment. Moreover, temperature by organ was higher in the high-temperature treatment than in the control treatment; consequently, the leaf transpiration rate and stomatal conductance were higher in the control treatment than in the high-temperature treatment. On all measuring dates, the weight of spikes and seeds corresponding to the sink organs was greater in the high-temperature treatment than in the control treatment. Additionally, the seed growth rate was higher in the high-temperature treatment than in the control treatment 14 days after heading, which may be attributed to the higher redistribution of photosynthates at the early stage of seed development in the former. In hyperspectral analysis, the vegetation indices related to leaf chlorophyll content and nitrogen state were higher in the high-temperature treatment than in the control treatment after heading. Our results suggest that elevated temperatures after the booting stage positively affect wheat growth and yield.

Changes in Sink capacity and Source Activity of Rice Cultivars in Response to Shift of Heading date (벼 품종들의 출수기에 따른 동화산물 생산능력 및 수용기관 크기 변화)

  • Lee, Sok-Young;Kwon, Yong-Woong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.2
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    • pp.260-267
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    • 1995
  • In temperate zone planting rice at different date subjects the Crop to different climatic condition. The present study aimed at comparison of the change in source-sink relationship of the Japonica(J) and that of IndicaxJaponica(I$\times$J) type rice cultivars caused by shift of heading date. Two J- and two I$\times$J-type cultivars were made to head on August 16, August 26, and September 5. Sink capacity was changed by shift of heading date in different mode between the types of cultivars. In both types major determinant of sink capacity was number of effective tillers, and the number of spikelets per panicle was the minor. In J-type earlier planting/heading was beneficial to increased panicle numbers and this was due mainly to a larger diurnal difference in temperature. I$\times$J-type cultivars favored a higher daily mean temperature to increase the sink capacity. The ability of source at heading, in terms of leaf area per panicle, chlorophyll content per spiklet, photosynthetic ability of leaves per unit area at 25$\^{\circ}C$, carbohydrate and N contents of leaves, was not so different among different heading dates in both types. However, the source activity was governed principally by temperature during grain filling. The J-type cultivars headed on Sept. 5 and I$\times$J-type cultivars headed later than August 16 could not have had sufficient source activity in grain filling due to lower temperature.

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Impact of East Asian Summer Atmospheric Warming on PM2.5 Aerosols (동아시아 지역의 여름철 온난화가 PM2.5 에어로졸에 미치는 영향)

  • So-Jeong Kim;Jae-Hee Cho;Hak-Sung Kim
    • Journal of the Korean earth science society
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    • v.45 no.1
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    • pp.1-18
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    • 2024
  • This study analyzed the effect of warming on PM2.5 aerosol production in mid-latitude East Asia during June 2020 using PM2.5 aerosol anomalies, which were identified by incorporating meteorological and climate data into the Weather Research Forecasting model coupled with Chemistry (WRF-Chem) model. The decadal temperature change trend over a 30-year period (1991-2020) in East Asia showed that recent warming has been greater in summer than in winter. Summer warming in East Asia generated low and high pressure in the lower and upper troposphere, respectively, over China. The boundary between the lower tropospheric low and upper tropospheric high pressure sloped along the terrain from the Tibetan Plateau to Korea. The eastern China, Yellow Sea, and Korean regions experienced a convergence of warm and humid southwesterly airflows originating from the East China Sea with the development of a northwesterly Pacific high pressure. In June 2020, the highest temperatures were observed since 1973 in Korea. Meanwhile, enhanced warming in East Asia increased the production of PM2.5 aerosols that travelled long distances from eastern China to Korea. PM2.5 anomalies, which were derived solely by inputting meteorological and climatic data (1991-2020) into the WRF-Chem model and excluding emission variations, showed a positive distribution extending from eastern China to South Korea across the Yellow Sea as well as over the Pacific Northwest. Thus, the contribution of warming to PM2.5 aerosols in East Asia during June 2020 was more than 50%. In particular, PM2.5 aerosols were transported from eastern China to Korea through the Yellow Sea, where the warm and humid southwesterly airflows implied wet scavenging of sulfate but promoted nitrate production.

Ecological Characteristics of Leading Shoot Elongation in the Plantation (I) (조림목(造林木) 신초생장(新稍生長)의 생태학적특성(生態學的特性)에 관(關)한 연구(硏究) (I))

  • Ma, Sang Kyu;Kuk, Ung Hum
    • Journal of Korean Society of Forest Science
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    • v.47 no.1
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    • pp.37-43
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    • 1980
  • This study have done to get the basical information that would be useful to make the ecological planting, selection of suitable species and weeding plan by the relation between the leading shoot elongation of several species and the climatic factors in the plantation. Sampling measurement have been done in the trial forest of Korean German Forest Management Project located in Joil-ri, Samnam-myeon and Ichcon-ri, Sangbug-myeon, Ulju-gun. The former is in lowland at 100m latidude and the latter is in highland of 600 m latitude. The elongation of leading shoot has been measured in the plantation with 10 days interval from the beginning of March in 1979 and the climatic datas has gotten in the weather station closed to the plantation. 1. The change of air temperature and rainfall in each measuring site is like Fig 1. and 2. The similar temperature in 600 m high latitude is coming about 10 days latter than 100 m latitude. 2. Genus pine as Pinus thunbergii, P. rigida, P. rigitaeda. P. koraiensis and P. taeda begin their leading shoot growth during March and air temperature in that time is around $6^{\circ}C$. In highland their beginning of leading shoot elongation has been found out 10 days latter than lowland. However Abies, Larix and Picea has shown to open their leading shoot during May, 40 days late in comparing with genus pine, and then temperature is making around $15^{\circ}C$. But Cryptomeria, Chamaecyparis and Cedrus deodora has shown their leading shoot opening in March in lowland and May in high land. The reason of late opening, specially in highland, seems to be the influence of winter frost. 3. Most of leading shoot elongation of genus pine has finished during the end 10 days of April and May under range of air temperate $10^{\circ}C$ and $20^{\circ}C$ and other species has finished most of their elongation during the end 10 days of May and June with air temperature range of $18^{\circ}C$ to $20^{\circ}C$. So the suitable season of weeding works show to genus pine in May and other species in June. 4. The leading shoot growth of genus pine has started earlier and closed earlier too than other species and, when over than $20^{\circ}C$ air temperature, their growth is decreasing quickly. Pices abies as well show to be decreased suddenly in over than $20^{\circ}C$ temperature. Other species show the similar trend when over than $22^{\circ}C$. This reason is considered as high temperature of summer season. 5. Annual elongated days of leading shoot of Picea abies is 50 days, Abies hollophylla 70 days, and more than 85 percentage of shoot growth of Pinus koraiensis and Larix leptolepsis are growing during 70 dys as well. The shoot growing days of Chamaecyparis, P. rigida, P. rigitaeda, P. taeda and P. shunbergii show longer period as over than 120 days. 6. The shoot elongation times per year of Abies and Picea has closed as one times and Genus pine is continuring their elongation more than two times. But Cryptomeria, Chamaecyparis, Cedrus deodora and Larix show one or two times elongation depending on the measuring site. The reason of continuring elongation more than than two times seems to be influenced by the temperature in summer season except the genetical reason. 7. Depending on the above results, as the high temperature in summer season could give the influence to grow the leading shoot in the plantation, this would be the considering point on the ecological planting and selection of the suitable species to the slope aspect. The elongation pattern by the season show to be the considering point too to decide the the weeding and fertilizer dressing time by the species.

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The Effects of Self-Determination on Entrepreneurial Intention in Office Workers: Focusing on the Dual Mediation of Innovativeness and Prception of the Startup Support System (직장인의 자기결정성이 창업의지에 미치는 영향: 혁신성과 창업지원정책인식의 이중매개를 중심으로)

  • Lim, Jae Sung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.19 no.1
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    • pp.75-91
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    • 2024
  • Recently, global business environment is changing dramatically along with the acceleration of technological innovation amid the war, climatic change, and geopolitical instability. Accordingly, it is difficult to predict or plan for the future as the volatility, complexity, ambiguity, and uncertainty of the industrial ecosystem continue to increase. Therefore, organizations are undergoing inevitable restructuring in accordance with their survival strategy, for instance, removing marginal businesses or firing. Accordingly, office workers are seeking a startup as an alternative for their continuous economic activity amid rising anxiety factors that make them think they would lose their jobs unintentionally. Here, this study is aimed to verify through what paths office workers' self-determination influences the process of converting to a startup. For this study, an online survey was carried out, and 310 respondents' valid data were analyzed through SPSS and AMOS. To sum up the results, first, office workers' self-determination did not have significant effects on entrepreneurial intention. However, it was confirmed that self-determination had positive (+) effects on innovativeness and perception of the startup support system. This result shows that their psychology works to prepare step by step by accumulating innovative experiences and increasing perception of the startup support system from a long-term life path perspective rather than challenging startups right way. Second, innovativeness is found to have positive (+) effects on entrepreneurial intention. Also, perception of the startup support system had positive (+) effects on entrepreneurial intention. This implies that when considering startups, they are highly aware of the government's various startup support systems. Third, innovativeness is found to have positive (+) effects on perception of the startup support system. It is judged that perception of the startup support system is valid for prospective founders to exhibit their innovativeness and realize new ideas. Fourth, it was confirmed that innovativeness and perception of the startup support system mediated correlation between self-determination and entrepreneurial intention, and perception of the startup support system mediated correlation between innovativeness and entrepreneurial intention, which shows that it is a crucial factor in entrepreneurial intention. Although previous studies related to startups deal with students mostly, this study targets office workers who form a great part in economic activities, which makes it academically valuable in terms of being differentiated from others and extending the scope of research. Also, when we consider the fact that the motivation for self-determination alone fails to stimulate entrepreneurial intention and the complete mediation of innovativeness and the startup support system, it has great implications in practical aspects such as the government's human and material support systems. In the selection and analysis of samples, this study exhibits a limitation that the problem of common method bias is not completely resolved. Also, additional definitive research is needed on whether entrepreneurial intention is formed and converted into startup behavior. Academically and practically, this study deals with the relationship between humans' psychological motives and startups which has not been handled sufficiently in previous studies. The conversion of office workers to startups is expected to have effects on individuals' economic stability and the state's job creation; therefore, it needs to be investigated continuously for its great value.

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Studies on the selection in soybean breeding. -II. Additional data on heritability, genotypic correlation and selection index- (대두육종에 있어서의 선발에 관한 실험적연구 -속보 : 유전력ㆍ유전상관, 그리고 선발지수의 재검토-)

  • Kwon-Yawl Chang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.3
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    • pp.89-98
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    • 1965
  • The experimental studies were intended to clarify the effects of selection, and also aimed at estimating the heritabilities, the genotypic correlations among some agronomic characters, and at calculating the selection index on some selective characters for the selection of desirable lines, under different climatic conditions. Finally practical implications of these studies, especially on the selection index, were discussed. Twenty-two varieties, determinate growing habit type, were selected at random from the 138 soybean varieties cultivated the year before, were grown in a randomized block design with three replicates at Chinju, Korea, under May and June sowing conditions. The method of estimating heritabilities for the eleven agronomic characters-flowering date, maturity date, stem length, branch numbers per plant, stem diameter, plant weight, pod numbers per plant, grain numbers per plant and 100 grain weight, shown in Table 3, was the variance components procedures in a replicated trial for the varieties. The analysis of covariance was used to obtain the genotypic correlations and phenotypic correlations among the eight characters, and the selection indexes for some agronomic characters were calculated by Robinson's method. The results are summarized as follows: Heritabilities : The experiment on the genotype-environment interaction revealed that in almost all of the characters investigated the interaction was too large to be neglected and materially affected the estimates of various genotypic parameters. The variation in heritability due to the change of environments was larger in the characters of low heritability than in those of high heritability. Heritability values of flowering date, fruiting period (days from flowering to maturity), stem length and 100 grain weight were the highest in both environments, those of yield(grain weight) and other characters were showed the lower values(Table 3). These heritability values showed a decreasing trend with the delayed sowing in the experiments. Further, all calculated heritability values were higher than anticipated. This was expected since these values, which were the broad sense heritability, contain the variance due to dominance and epistasisf in addition to the additive genetic variance. Genotypic correlations : Genotypic correlations were slightly higher than the corresponding phenotypic correlations in both environments, but the variation in values due to the change of environment appeared between grain weight and some other characters, especially an increase between grain weight and flowering date, and the total growing period(Table 6). Genotypic correlations between grain weight and other characters indicated that high seed yield was genetically correlated with late flowering, late maturity, and the other five characters namely branch numbers per plant, stem diameter, plant weight, pod numbers per plant and grain numbers per plant, but not with 100 grain weight of soybeans. Pod numbers and grain numbers per plant were more closely correlated with seed yields than with other characters. Selection index : For the comparison and the use of selection indexes in the selection, two kinds of selection indexes were calculated, the former was called selection index A and the later selection index B as shown in Table 7. Selection index A was calculated by the values of grain weight per plant as the character of yield(character Y), but the other, selection index B, was calculated by the values of pod numbers per plant, instead of grain weight per plant, as the character of yield'(character Y'). These results suggest that selection index technique is useful in soybean breeding. In reality, however, as the selection index varies with population and environment, it must be calculated in each population to which selection is applied and in each environment in which the population is located. In spite of the expected usefulness of selection index technique in soybean breeding, unsolved problems such as the expense, time and labor involved in calculating the selection index remain. For these reasons and from these experimental studies, it was recognized that in the breeding of self-fertilized soybean plants the selection for yield should be based on a more simple selection index such as selection index B of these experiments rather than on the complex selection index such as selection index A. Furthermore, it was realized that the selection index for the selection should be calculated on the basis of the data of some 3-4 agronomic characters-maturity date(X$_1$), branch numbers per plant(X$_2$), stem diameter(X$_3$) and pod numbers per plant etc. It must be noted that it should be successful in selection to select for maturity date(X$_1$) which has high heritability, and the selection index should be calculated easily on the basis of the data of branch numbers per plant(X$_2$), stem diameter(X$_3$) and pod numbers per plant, directly after the harvest before drying and threshing. These characters should be very useful agronomic characters in the selection of Korean soybeans, determinate growing habit type, as they could be measured or counted easily thus saving time and expense in the duration from harvest to drying and threshing, and are affected more in soybean yields than the other agronomic characters.

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