• Title/Summary/Keyword: Reciprocal

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Qualitative Inquiry into the Characteristics of Science Teacher Learning Communities: Cases Within and Across Schools (과학 교사 학습공동체 특성에 대한 질적 탐구 -학교안과 학교밖 공동체 사례-)

  • Kwak, Youngsun;Lee, Ki-Young;Jeong, Eunyoung
    • Journal of The Korean Association For Science Education
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    • v.41 no.4
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    • pp.297-310
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    • 2021
  • This study explores the characteristics of within-school and across-school science teacher professional learning communities (hereafter, PLC) qualitatively. In-depth focus group interviews were conducted with science teachers belonging to seven PLCs within the science core school and three PLCs across schools. Interview questions include identity and motivation, major activities, and outcomes of PLC, as well as shortcomings and support plans for PLC. The results include both within-school and across-school science teacher PLCs formed for professional development related to science teaching and learning. Both science PLCs participated in the study showed the characteristics of a 'practice community' that developed a cooperative relationship through reciprocal participation, focusing on shared issues among members. Regarding issues, within-school PLCs focused on microscopic problems such as curriculum reconstruction of subject-matter, while across-school PLCs focused on macro problems such as teacher professional development. Regarding activities and roles as PLC, within-school and across-school science PLCs shared such features as collaborative professional development, and interpersonal education such as mentoring for novice teachers. In terms of PLC's influence and outcomes, science teacher PLCs has a positive effect not only on the teachers themselves, but also on the students and the teacher culture in the school. In addition, science teacher PLCs need improvement of the physical conditions for community operation, and software support such as protocol provision for PLC operation and joint research or re-education with universities. In particular, joint research between universities and science teacher PLCs shows the future orientation of the PLC as an 'inquiry community'. Based on the results, the necessity of active support for science PLC, the necessity of developing a cooperative system between science teacher PLC and universities, and ways to spread the PLC of science core schools to that of general schools were proposed.

Examining the Relationship Among Restaurant Brand Relationship Quality, Attribution, and Emotional Response After Service Failure Experience (서비스 실패 경험 후 레스토랑 브랜드 품질, 귀인 및 감정반응 관계분석)

  • Jang, Gi-Hwa;Song, Soo-Ik;Oh, Sung-Cheon
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.4
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    • pp.1120-1133
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    • 2018
  • The purpose of this study is to validate the failure attribution factors affecting emotional changes after a failed service by local restaurant users, and the relapse effects of the perceived failure of a customer's brand relationship. In this study, the implications of this study can be divided into the null theory and the homogenous theory, in which the study of the relationship between individual belief that influences the null theory and the post-gender emotional response is minimal. The independence of the crash response (angerous VS compassion) has been equally validated as building a belief-gathering-emotion three-step model. First, emotional BRQ (intimate and love) has a reduction effect on controllable geeks, and behavioral BRQ (relative existence) has an extended effect on controllable geeks. From a management perspective, restaurant managers should be less aware of the repeatability of a customer's service failure and call for customer sympathy. Integratedly, restaurant managers must control the customer's perception of service failure and restore the impact of the customer's BRQ on emotional reactions. A variety of service recovery measures should be established and the cerumen should be controlled. In addition, since BRQs have different effects on anger and sympathy (extended VS), different service failure recovery plans should be presented depending on the characteristics of the customer BRQ. For example, measures such as monetary compensation or fair dealing, emotional distribution to close and loving customers, and persuasion of reciprocal benefits to interdependent customers should be developed according to circumstances. This study explored the effectiveness of the geeks after a service failure and has limitations that do not take into account the various regulatory factors in the BRQ-return-Empression process. Thus, in further studies, the effects of adjusting service failure strength should be considered and a more complete model should be built.

Long-term and Short-term Reciprocity in Parent-Child Relations for Korean Sons and Daughter (세대 간 지원교환의 장기적·단기적 호혜성: 아들과 딸의 비교)

  • Choi, Heejin;Han, Gyoung-hae
    • 한국노년학
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    • v.37 no.1
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    • pp.83-102
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    • 2017
  • Expending on a life course perspective, this study explores the long-term and short-term reciprocity in parent-child relationships in Korean context. Since the reasons for providing filial support are believed to differ by gender, we focused on how a child's gender affects both types of reciprocity. Data were collected from middle-aged sons (N=726) and daughters (N=883) with at least one surviving parent. Logistic regression was then conducted in order to examine the relations between the support a child currently provides to parents and the current or previous support received from the parents. Dependent variables are financial and instrumental support that middle-aged child currently provide to the parents. The financial and instrumental support a child received from the parents within a year are included in the model as an independent variable to assess short-term reciprocity. The level of financial support a child has received during the transition to adulthood process is included in the model as a independent variable to explore long-term reciprocity. Result supports the existence of gender differences in the long-term reciprocity. Daughters provided instrumental support in response to the financial support that they had received from parents during the transition to adulthood process. However, for sons, this tendency was not found. When it comes to financial support, long-term reciprocity was observed neither for the sons nor for the daughters. Both sons and daughters are prone to provide financial support to the aged parents regardless of the level of financial support they had received during the transition to adulthood process. Short-term reciprocity was found both in sons and daughters. when they have been receiving a financial or an instrumental support from the aged parents within a year, they tend to provided instrumental support to the parents. This study shows that the aged parents still fulfill the reciprocal relationship to a certain degree. Secondly, we can conclude that the norm of reciprocity interplays with the norm of filial responsibility in contemporary Korea.

A Study on the Comparison of Liang Shu-Ming and Lee Don-Hwa's Perceptions of Modernization and the Philosophical Grounds of their Perceptions : Focusing on Works during the New Cultural Movement Period in Korea and China (양수명과 이돈화의 근대화에 대한 견해 및그 철학적 근거에 대한 비교 연구 - 한·중 신문화운동 시기의 저작을 중심으로 -)

  • Hwang, Jong Won
    • The Journal of Korean Philosophical History
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    • no.36
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    • pp.319-352
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    • 2013
  • This paper aims to compare Liang Shu-Ming and Lee Don-Hwa's perceptions of modernization and the philosophical grounds of their perceptions during the New Cultural Movement period in Korea and China. Although Liang and Lee had different levels of enthusiasm towards New Cultural Movement, they shared many commonalities in their attitudes to Western modernization and their philosophical justifications for such attitudes. Liang Shu-Ming not only held positive views of Western modernization, but also examined the spiritual dynamics contributing to the development in science and democracy in Western countries. By analyzing the three fundamental questions of life, three kinds of human attitudes toward life, three types of culture derived from human attitudes, and the recapitulation theory, Liang systematically reviewed the spiritual dimension of Western modernization. Liang defined the spirit of Western modernization as a calculative rationality based on egoism and the separation of Self and Other. Such a statement demonstrates Liang's keen insights towards Western modernization. Meanwhile, although Lee Don-Hwa basically held positive views of Western modernization, from the beginning, he pointed out the problems with Western modernization and attempted to overcome these problems by employing the "human is heaven" doctrine of Cheondogyo. While Lee embraced modern science and the theory of evolution, he also insisted on the legitimacy of mysticism and the compatibility of the creation theory of Cheondogyo and the theory of evolution. Although Lee employed the concepts in Western philosophy of life, he also emphasized the interdependence, reciprocal relationship, and connectedness between Self and Other from the perspective of Cheodogyo doctrine. From the fact that Lee Don-Hwa transcended the modernization theory when he was applying it to answer questions, it seemed that Lee preceded Liang Shu-Ming. Nevertheless, Lee did not demonstrate the keen insight into the spiritual dimension of Western modernization, and his criticism against Western modernization did not touch upon the problem of rationality as Liang did.

Does Science Motivation Lead to Higher Achievement, or Vice Versa?: Their Cross-Lagged Effects and Effects on STEM Career Motivation (과학 학습 동기가 높은 학생이 과학 학업 성취도가 높아지는가, 또는 그 역인가? -양자가 지닌 교차지연 효과 및 이공계 진로 동기에 미치는 효과-)

  • Lee, Gyeong-Geon;Mun, Seonyeong;Han, Moonjung;Hong, Hun-Gi
    • Journal of The Korean Association For Science Education
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    • v.42 no.3
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    • pp.371-381
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    • 2022
  • This study causally investigates whether high school student with high science learning motivation becomes to achieve more or vice versa, and also how those two factors affect STEM career motivation. Research participants were 1st year students in a high school at Seoul. We surveyed their science learning motivation three times in the same time interval in the fall semester of 2021, and once a STEM career motivation in the third period. We collected data from 171 students with their mid-term and final exam scores, with which, we constructed and fitted an autoregressive cross-lagged model. The research model shows high measurement stability and fit indices. All the autoregressive and cross-lagged paths were statistically significant. However, standardized regression coefficients were larger in path from motivation to achievement compared to the opposite. Only science learning motivation shows significant direct effect on STEM career motivation, rather than achievement. For indirect effects, the first science learning motivation affected the final exam score and STEM career motivation, and the final exam score affected STEM career motivation. However, the final exam score did not have a total effect toward STEM career motivation. The result of this study shows reciprocal and cyclic causality between science learning motivation and achievement - in comparison, the effect of motivation for the opposite is larger than that of achievement. Also the result of this study strongly reaffirms the importance of science learning motivation. Instructional implications for strengthening science learning motivation throughout a semester was discussed, and a study for the longitudinal effect of science learning motivation and achievement in high school student toward future STEM vocational life was suggested.

Introduction of region-based site functions into the traditional market environmental support funding policy development (재래시장 환경개선 지원정책 개발에서의 지역 장소적 기능 도입)

  • Jeong, Dae-Yong;Lee, Se-Ho
    • Proceedings of the Korean DIstribution Association Conference
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    • 2005.05a
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    • pp.383-405
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    • 2005
  • The traditional market is foremost a regionally positioned place, wherein the market directly represents regional and cultural centered traits while it plays an important role in the circulation of facilities through reciprocal, informative and cultural exchanges while sewing to form local communities. The traditional market in Korea is one of representative retail businesses and premodern marketing techniques by family owned business of less than five members such as product management, purchase method, and marketing patterns etc. Since the 1990s, the appearance of new circulation-type businesses and large discount convenience stores escalated the loss of traditional competitiveness, increased the living standard of customers, changed purchasing patterns, and expanded the ubiquity of the Internet. All of these changes in external circulation circumstances have led the traditional markets to lose their place in the economy. The traditional market should revive on a regional site basis through the formation of a community of regional neighbors and through knowledge-sharing that leads to the creation of wealth. For the purpose of creating a wealth in a place, the following components are necessary: 1) a facility suitable for the spatial place of the present, 2)trust built through exchanges within the changing market environment, which would simultaneously satisfy customer's desires, 3) international bench marking on cases such as regionally centered TCM (England), BID (USA), and TMO (Japan) so that the market unit of store placement transfers from a spot policy to a line policy, 4)conversion of communicative conception through a surface policy approach centered around a macro-region perspective. The budget of the traditional market funding policy was operational between 2001 and 2004, serving as a counter move to solve the problem of the old traditional market through government intervention in regional economies to promote national economic strength. This national treasury funding project was centered on environmental improvement, research corps, and business modernization through the expenditure of 3,853 hundred million won (Korean currency). However, the effectiveness of this project has yet to be to proven through investigation. Furthermore, in promoting this funding support project, a lack of professionalism among merchants in the market led to constant limitations in comprehensive striving strategies, reduced capabilities in middle-and long-term plan setup, and created reductions in voluntary merchant agreement solutions. The traditional market should go beyond mere physical place and ordinary products creative site strategies employing the communicative approach must accompany these strategies to make the market a new regional and spatial living place. Thus, regarding recent paradigm changes and the introduction of region-based site functions into the traditional market, acquiring a conversion of direction into the newly developed project is essential to reinvestigate the traditional market composed of cultural and economic meanings, for the purpose of the research. Excavating social policy demands through the comparative analysis of domestic and international cases as well as innovative and expert management leadership development for NPO or NGO civil entrepreneurs through advanced case research on present promotion methods is extremely important. Discovering the seeds of the cultural contents industry cored around regional resource usages, commercializing regionally reknowned products, and constructing complex cultural living places for regional networks are especially important. In order to accelerate these solutions, a comprehensive and systemized approach research operated within a mentor academy system is required, as research will reveal distinctive traits of the traditional market in the aging society.

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Dreams of Admiral Yi Sun-sin (1545-1598) in Nanjung Ilgi (Diary in War Time) and Some Aspects of His Personality: From Jungian Viewpoint (≪난중일기≫에서 본 이순신의 꿈과 인격의 몇 가지 측면: 분석심리학적 입장에서)

  • Bou-Yong Rhi
    • Sim-seong Yeon-gu
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    • v.37 no.2
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    • pp.99-148
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    • 2022
  • This study aims at the psychological elucidation of some conscious aspects of the personality of Yi Sun-sin (1545-1598), the Korean national hero, and the unconscious teleologic meanings of his dreams mentioned in Nanjung Ilgi (Diary in War Time) from the viewpoint of analytical psychology of C.G. Jung. Yi Sun-sin was a man of discipline, incorporated with the spirit of Confucian filial piety, hyo (hsiao) and royalty, chung. He was a stern man but with a warm heart. In his diary, Yi Sun-sin poured forth his feelings of suffering, despair, and extreme solicitude caused by slanders of his political opponents, his grief for the loss of mother and son, and his worries about the fate of his country, which the Japanese invaders now plundered. The moon night offered him the opportunity to touch with his inner soul, by reciting poems, playing Korean string, 'Keomungo', and flute. Further, he widened his scope by asking for the answers from the 'Heaven' through divination and dream. Yi Sun-sin's attitude toward his mother who raised the future hero and maternal principles were considered in concern with the Jungian term 'mother complex'. Won Gyun, Yi Sun-sin's rival admiral, who persistently accused Yi Sun-sin of 'slanders,' certainly represents the unconscious shadow image of Yi Sun-sin. The reciprocal 'shadow' projection has intervened in the conflicting relationship between Yi and Won. In concern to the argument for the suicidal death of Yi Sun-sin, the author found no evidence supporting such an argument, No trace of latent suicidal wish was found in his dreams. For Yi Sun-sin, the determination of the life and death depends on Heaven. 32 dreams from the diary and 3 from other historical references were reviewed and analyzed in the Jungian way. Symbols of anima, Self, and individuation process were found. His dream repeatedly suggests that Yi Sun-sin is an extraordinary man chosen by the divine man (神人). In the dream, Yi Sun-sin was a disciple of the divine man receiving instructions on various strategies, and he alone could see the great thing or events. The dream of a beautiful blue and red dragon, whom he was friendly touching, indicates Yi Sun-sin's eligibility for the kingship. Yi Sun-sin seemingly did not aware of this message of the unconscious. Perhaps he sensed something special but did not identify with 'the disciple of gods' and 'royal dragon' in his dream. His modest attitude toward the dream has prevented him from falling into ego inflation. There were warning signals in two dreams that suggested disorders in the dreamer's instinctive feminine drive. Spirits of the dead father and brothers appear in the dream, giving advice or mourning for the death of Sun-sin's mother. Though Yi Sun-sin was a genuine Confucian gentleman, a dream revealed his unconscious drive to destroy the Confucian authoritative 'Persona' by trampling down the cylindrical traditional Korean hat. To the dreams of synchronicity phenomena Yi Sun-sin immediately solves the problem in concrete reality. He understood dreams as valuable messages from the superior entity, for example, the Confucian Heaven (天) or Heaven's Decree (天命). Furthermore, the 'Heaven' presumably arranged for him the way to the national hero and imposed necessary trials upon him. Both his persecutors and advocates of him guided him in the way of a hero. Yi Sun-sin followed his destiny and completed the living myth of the hero. His mother, King Seon-jo, and prime minister Liu Seong Yong, all have contributed to embodying the myth of the hero. Yi Sun-sin died and became god, the divine healer of the nation.

A Study on Estimation of Edible Meat Weight in Live Broiler Chickens (육용계(肉用鷄)에서 가식육량(可食肉量)의 추정(推定)에 관(關)한 연구(硏究))

  • Han, Sung Wook;Kim, Jae Hong
    • Korean Journal of Agricultural Science
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    • v.10 no.2
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    • pp.221-234
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    • 1983
  • A study was conducted to devise a method to estimate the edible meat weight in live broilers. White Cornish broiler chicks CC, Single Comb White Leghorn egg strain chicks LL, and two reciprocal cross breeds of these two parent stocks (CL and LC) were employed A total of 240 birds, 60 birds from each breed, were reared and sacrificed at 0, 2, 4, 6, 8 and 10 weeks of ages in order to measure various body parameters. Results obtained from this study were summarized as follows. 1) The average body weight of CC and LL were 1,820g and 668g, respectively, at 8 weeks of age. The feed to gain ratios for CC and LL were 2.24 and 3.28, respectively. 2) The weight percentages of edible meat to body weight were 34.7, 36.8 and 37.5% at 6, 8 and 10 weeks of ages, respectively, for CC. The values for LL were 30.7, 30.5 and 32.3%, respectively, The CL and LC were intermediate in this respect. No significant differences were found among four breeds employed. 3) The CC showed significantly smaller weight percentages than did the other breeds in neck, feather, and inedible viscera. In comparison, the LL showed the smaller weight percentages of leg and abdominal fat to body weight than did the others. No significant difference was found among breeds in terms of the weight percentages of blood to body weight. With regard to edible meat, the CC showed significantly heavier breast and drumstick, and the edible viscera was significantly heavier in LL. There was no consistent trend in neck, wing and back weights. 4) The CC showed significantly larger measurements body shape components than did the other breeds at all time. Moreover, significant difference was found in body shape measurements between CL and LC at 10 weeks of age. 5) All of the measurements of body shape components except breast angle were highly correlated with edible meat weight. Therefore, it appeared to be possible to estimate the edible meat wight of live chickens by the use of these values. 6) The optimum regression equations for the estimation of edible meat weight by body shape measurements at 10 weeks of age were as follows. $$Y_{cc}=-1,475.581 +5.054X_{26}+3.080X_{24}+3.772X_{25}+14.321X_{35}+1.922X_{27}(R^2=0.88)$$ $$Y_{LL}=-347.407+4.549X_{33}+3.003X_{31}(R^2=0.89)$$ $$Y_{CL}=-1,616.793+4.430X_{24}+8.566X_{32}(R^2=0.73)$$ $$Y_{LC}=-603.938+2.142X_{24}+3.039X_{27}+3.289X_{33}(R^2=0.96)$$ Where $X_{24}$=chest girth, $X_{25}$=breast width, $X_{26}$=breast length, $X_{27}$=keel length, $X_{31}$=drumstick girth, $X_{32}$=tibotarsus length, $X_{33}$=shank length, and $X_{35}$=shank diameter. 7) The breed and age factors caused considerable variations in assessing the edible meat weight in live chicken. It seems however that the edible meat weight in live chicken can be estimated fairly accurately with optimum regression equations derived from various body shape measurements.

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A Study on the Religiosity of Filial Piety Ethics in Daesoonjinrihoe (대순진리회의 효 윤리에 나타난 종교성 연구)

  • Cha, Seon-keun
    • Journal of the Daesoon Academy of Sciences
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    • v.27
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    • pp.171-200
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    • 2016
  • This paper will analyze the filial piety based ethics of Daesoonjinrihoe (大巡眞理會) and the traditional filial piety of Confucianism (儒敎), Buddhism (佛敎) and Taoism (道敎) through comparing and contrasting their unique systems. The traditional Korean ethics regarding filial piety are in great need of reformation as the relationship between the parents and children should not be vertical or unilateral but parallel and reciprocal. However, there have not been sufficient in-depth studies on this specific ideology and alternative approaches. Regarding this prospect, one representative Korean indigenous new religion, Daesoonjinrihoe has emerged and directly engages in the collision between traditionalism and modernity. The modernity of Daesoonjinrihoe, enables the observation of how the filial piety based ethics have developed within a system of doctrine and thereby provides an exemplary model of traditional filial piety reimagined in accordance with modern sensibilities. A brief summary of comparative findings is as follows: First, Daesoonjinrihoe and Confucianism have taken serving parents with respect as an ethic within filial piety, but Confucianism engenders this ideal through the unilateral and unconditional sacrifice of younger people based on patriarchal feudalism whereas Daesoonjinrihoe has rejected such unilateral sacrifice and instead promotes mutual beneficience between parents and children. This difference occurs, in part, due to the filial piety of Confucianism rising in the midst of the feudal order whereas the ideology of Daesoonjinrihoe contains ideals such as "the reciprocation of favor for mutual beneficence (報恩相生)" and "respect for humanity (人尊)," both of which serve as key principles of the new religious world as envisioned by Daesoonjinrihoe. Second, filial piety in Buddhism and Taoism tends to be passive and inactive and is often expressed by praying for happiness and longevity for one's parents while they are alive and later praying for the heavenly rebirth of one's parents after they die. The filial piety of Daesoonjinrihoe also partially contains such ideas, however; they are extended much further and arrive upon novel and profound expressions. The spectrum of the filial piety in Daesoonjinrihoe expands to the extent children perform actions to resolve their parent's sins and pave a new road for their parents. This filial piety requires a cultivation practice from both parents and children. This system of dual cultivation was established because the world-view of Daesoonjinrihoe enables both parents and children to enjoy happiness and wealth both of which are achieved through the completion of religious objectives following cultivation practice. Third, Confucianism and Daesoonjinrihoe hold memorial services for ancestors with sincerity as an expression of filial piety. Filial piety in the Confucian context excludes ideas from Shamanism and thereby memorial services are held for impersonal entities, however; in the Daesoonjinrihoe context, memorial services are held for personal-entities. Accordingly, holding a memorial service for ancestors with sincerity has a greater sense of realism in Daesoonjinrihoe than it does in Confucianism. Fourth, while Confucianism and Daesoonjinrihoe both aim to requite the grace received from ancestors, the contents of grace and reciprocation of favors (報恩) are viewed differently. In Confucianism, since the ancestors existed previously and bestowed the gift of life to their children and indirectly, all of their descendents. Therefore, memorial services for ancestors are held to convey gratitude and filial piety. However, in Daesoonjinrihoe, ancestors not only bestowed the gift of earthly life to their descendents, in the spirit realm, ancestral spirits also spend sixty years accumulating the merit necessary to imbue each of their descendents with spiritual insight. Consequently, filial piety is expressed through memorial services as well as spiritual cultivation. Fifth, in Confucianism, achieving the fame and prestige indicative of success in the mundane world can be an act of filial piety as it would bring pride to one's ancestors, but in Daesoonjinrihoe, succeeding in religious objectives through spiritual cultivation is considered to be a higher form of filial piety. Sixth, Confucianism, Buddhism and Taoism all observe filial piety as system of familial ethics based in morality. This is likewise true of Daesoonjinrihoe, however; Daesoonjinrihoe confers greater importance on filial piety as an essential form of ethics for religious redemption. This is due to the Daesoon interpretation that the absence of filial piety was the direct cause which led to the sickened state of the world and its collapse. Forgetting the grace of parents who have given the gift of life or the grace of ancestral spirits who have accumulated merit on behalf of their descendents are acts of ingratitude which are unacceptable during the period of Reordering of the Universe. Judging from these findings, Daesoonjinrihoe embraces parts of traditional filial piety as it exists in Confucianism, Buddhism and Taoism, but it does so on the ground of its own unique culture. Through re-interpretation and re-creation, ideas regarding filial piety are being further developed. Namely, filial piety in Daesoonjinrihoe is regulations founded upon the reciprocation of favors for mutual beneficence and respect for humanity. Therefore, it is understood as a concept wherein one's own cultivation practice is performed in order to reach religious objectives, the perfection of personal character, and spiritual insight. This requires that even recipents of filial piety (i.e., parents) perform certain cultivation practices to enjoy happiness and wealth. Additionally, filial piety in Daesoonjinrihoe manifests a reinforced religious character and also serves as a system ethics which is soteriologically essential for salvation during the period known as the Reordering of the Universe.

ON THE EFFECTS CHLORINITIES UPON GROWTH OF EARLIER LARVAE AND POST-LARVA OF A FRESH WATER PRAWN, MACROBRACHIUM ROSENBERGI(DE MAN) (담수산새우 Macrobrachium rosenbergi (de Man)의 초기유생 및 Post-larva.의 성장에 미치는 염분량에 관하여)

  • KWON Chin Soo;UNO Yutaka;OGASAWARA Yohismitsu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.10 no.2
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    • pp.97-114
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    • 1977
  • The fresh water prawn, Macrobrachium rosenbergi(de Man) is a very common species in Indopacific region, which inhaits both fresh and brackish water in low land area, most of rivers and especially aboundant in the lower reaches which are influenced by sea water. It is one of the largest and commercial species of genus Macrobrachium, which is commonly larger than $18\~21cm$ in body length, from the basis of eye-stalked to the distal of telson. As a part of the researches in order to investigate the possibilities on transplantation and propagation of this species, this work dealt with the problems on the effects of chlorinities upon zoeal larvae and post-larvae 1). metamorphosis rate and optimum chlorinity for metamorphosis to post-larve, 2). tolerance and comparative survival rate on various chlorinties, from fresh water to sea water $(19.38\%_{\circ}\;Cl)$, which reared for six days upon each stage of zoeal larvae, 3). accomodation rate on chlonities which reared for twelve days after transmigration into variant chlorinities of the range from $3.68\%_{\circ}$ Cl to $1.53\%_{\circ}$ Cl in the way of rearing of the range from $3.82\%_{\circ}$ Cl to $11.05\%_{\circ}$ upon each stage of zoea, 4). tolerance on both of fresh and sea water upon zoeal larva and post-larva under the condition of $28^{\circ}C{\pm}1$ in temperature and feeding on Artenia salina nauplii, 5). relationship between various chlorinities and grwth of post-larvae under the condition of $28^{\circ}C$ in tmperature and feeding on meat of clam. Thus these investigations were performed in order to grope for a comfortable method on seedmass production. Up to the present, the study on the effects of chlorinity upon earlier zoeal larvae and post-larvae of Macrobrachium species has been scarcely performed by workers with the exception of Lewis(1961) and Ling (1962,, 1967), even so their works were not so detailed. On the other hand, larvae of several species of this genus were reared at the water which mixed sea water so as to carry out complete metamorphosis to post-larva by workers in order to investigate on earlier 1 arval and earlier post-larval development, such as Macrobrachium lamerrei (Rajyalakshmi, 1961), M. rosenbergi and M. nipponense (Uno and Kwoa, 1969; Kwon and Uno, 1969), M. acanthurs (Choudhury, 1970; Dobkin, 1971), M. carcinus(Choudhury, 1970), M. formosense(Shokita, 1970), M. olfersii (Duggei et al., 1975), M. novaehallandiae (Greenwood et al., 1976), M. japonicum (Kwon, 1974) and M. lar (Shokita, personal communication), and there fore it is regarded that chlorinity is, generally, one of absolute factors to rear zoeal larvae of brackish species of Macrobrachium genus. Synthetic results on this work is summarized as the follwings: 1) Zoeal larvae required different chlorinities to grow according to each stage, and generally, it is regarded that optimum range of living and growing is from $7.63\%_{\circ}Cl\to\;7.63\%_{\circ}Cl$, and while differences of metamorphsis rate, from first zoea to post-larva, is rarely found in this range, and however it occurs apparently in both of situation at $7.63\%_{\circ}Cl$ below and $16.63\%_{\circ}Cl$ above and moreover, metamorphosis rate is delayed somewhat in case of lower chlorinity as compared with high chlorinity in these situations. 2) Accomodation in each chlorinity on the range, from fresh water to sea water, is different according to larval stages and while the best of it is, generally, on the range from $14.24\%_{\circ}Cl$ to $8.28\%_{\circ}Cl$ and favorite chlorinity of zoea have a tendency to remove from high chlorinity to lower chlorinity in order to advance larval age throughout all zoeal stages, setting a conversional stage for eighta zoea stage. 3) Optimum chlorinity of living and growth upon postlarvae is on the range of $4.25\%_{\circ}Cl$ below, and in proportion as approach to fresh water, growth rate is increased. 4) Post-large are able to live better in fresh water in comparison with zoeal larvae, which are only able to live within fifteen hours, and by contraries, post-larvae are merely able to live for one day as compared with ?미 larvar, which are able to live for six days more in sea water $19.38\%_{\circ}Cl\;above$. 5) Also, in case of transmigration into higher and lower chlorinities in the way of rearing in the initial chlorinities $ 3.82\%_{\circ}Cl,\;7.14%_{\circ}Cl\;and\;11.05%_{\circ}Cl$, accoodation rate is a follow: accomodation capacity in ease of removing into higher chlorinities from lower chlorinities is increased in proportion as earlier stages, setting a conversional stage for eighth zoea stage, and by contraries, in case of advanced stages from eighth zoea it is incraesed in proportion as approach to post-larva stage in the case of transmigration into lower chlorinity from higher chlorinity. On the other hand, it is interesting that in case of reciprocal transmigration between two different chlorinitiess, each survival rate is different, and in this case, also, its accomodation in each zoea stage has a tendency to vary according to larval stages as described above, setting a conversional stage for eighth zoea stage. 6) It is likely that expension of radish pigments on body surface is directly proportional to chlorinity during the period of zoea rearing, and therefore it seems like all body surfacts of zoea larvae be radish coloured in case of higher chlorinity. 7) By the differences that each zoeal larvae, postlarvae, juvaniles and adult prawn are required different chlorinity for inhabiting in each, it is regarded that this species migrats from up steam to near the estuary of the river which the prawns inhabits commonly in natural field for spawning and growth migration. 8) It had better maintainning chlorinities according to zoeal stage for a comfortable method on seed-mass production that earlier larva stages than eighth zoea are maintained on the range from $8\%_{\circ}Cl\;to\;12\%_{\circ}Cl$ to rear, and later larva stages than eighth zoea, by contraries, are gradually regula ted-to love chlorininity of the range from $7\%_{\circ}Cl\;to\;4\%_{\circ}Cl$ according to advance for post-larva stage.

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