• Title/Summary/Keyword: The Universe and the Earth

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FORMATION OF PROTO-GLOBULAR CLUSTER CLOUDS BY THERMAL INSTABILITY

  • KANG HYESUNG;LAKE GEORGE;RYU DONGSU
    • Journal of The Korean Astronomical Society
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    • v.33 no.2
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    • pp.111-121
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    • 2000
  • Many models of globular cluster formation assume the presence of cold dense clouds in early universe. Here we re-examine the Fall & Rees (1985) model for formation of proto-globular cluster clouds (PGCCs) via thermal instabilities in a protogalactic halo. We first argue, based on the previous study of two-dimensional numerical simulations of thermally unstable clouds in a stratified halo of galaxy clusters by Real et al. (1991), that under the protogalactic environments only nonlinear (${\delta}{\ge}1$) density inhomogeneities can condense into PGCCs without being disrupted by the buoyancy-driven dynamical instabilities. We then carry out numerical simulations of the collapse of overdense douds in one-dimensional spherical geometry, including self-gravity and radiative cooling down to T = $10^4$ K. Since imprinting of Jeans mass at $10^4$ K is essential to this model, here we focus on the cases where external UV background radiation prevents the formation of $H_2$ molecules and so prevent the cloud from cooling below $10^4$ K. The quantitative results from these simulations can be summarized as follows: 1) Perturbations smaller than $M_{min}\~(10^{5.6}\;M{\bigodot})(nh/0.05cm^{-3})^{-2}$ cool isobarically, where nh is the unperturbed halo density, while perturbations larger than $M_{min}\~(10^8\;M{\bigodot})(nh/0.05cm^{-3})^{-2}$ cool isochorically and thermal instabilities do not operate. On the other hand, intermediate size perturbations ($M_{min} < M_{pgcc} < M_{max}$) are compressed supersonically, accompanied by strong accretion shocks. 2) For supersonically collapsing clouds, the density compression factor after they cool to $T_c = 10^4$ K range $10^{2.5} - 10^6$, while the isobaric compression factor is only $10^{2.5}$. 3) Isobarically collapsed clouds ($M < M_{min}$) are too small to be gravitationally bound. For supersonically collapsing clouds, however, the Jeans mass can be reduced to as small as $10^{5.5}\;M_{\bigodot}(nh/0.05cm^{-3})^{-1/2}$ at the maximum compression owing to the increased density compression. 4) The density profile of simulated PGCCs can be approximated by a constant core with a halo of $p{\infty} r^{-2}$ rather than a singular isothermal sphere.

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International Comparative Study on Astronomical Exhibits: Focus on Exhibit Characteristics and Earth Science Curriculum Reflected in Exhibits (천체 전시물 비교 연구 -전시특성 및 지구과학 교육과정의 반영 정도를 중심으로-)

  • Kim, Soo Kyung;Park, Eun Ji;Kim, Chan Jong;Choe, Seung Urn
    • Journal of The Korean Association For Science Education
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    • v.36 no.6
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    • pp.925-934
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    • 2016
  • For students, astronomy is not only interesting but also difficult to learn. However, there is a limit in learning astronomy in a school science setting since astronomy is vast subject. Fortunately, science museums can be helpful in overcoming this limitation. Experiences in science museum provide something that any descriptions or illustrations cannot give. Therefore, to maximize the educational effect, it is necessary to look at astronomical exhibits regarding the educational aspects and complement them. For these reasons, the purpose of this study is to investigate characteristics of exhibitions related to astronomy and how much the exhibitions reflect the contents of their science curricula. We selected famous science museums in Korea, America, and Japan and analyzed characteristics of their astronomy exhibition. We analyze these characteristics in the aspects of exhibition technology & media, presentation method and activity types. Also, this study figures out how content of exhibitions are connected to school science curriculum. The results are summarized as follows: First, Science Museums of America and Japan utilize interactive exhibits to raise participation. It implies that Science Museum of Korea needs Interactive Exhibits that provide a realistic experience of the universe. Second, the astronomy exhibits reflect some of the learning elements of their science curricula concerned with astronomy. However, these astronomical contents are included selectively and not according to their required curriculum. It means that many students lack the opportunity to study Astronomy in their schools. Therefore, the astronomy museum must reflect learning elements of science curricula concerned with astronomy in the exhibits.

A Study on the Meaning of 'Gyoun' and Earlier Variations of Chapter One of 'Gyoun' in The Canonical Scripture (『전경(典經)』 「교운(敎運)」편 1장에 나타난 교운의 의미와 구절의 변이 연구)

  • Ko, Nam-sik
    • Journal of the Daesoon Academy of Sciences
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    • v.36
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    • pp.153-199
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    • 2020
  • The teachings of Sangje teachings have been spread to humanity and were provided as basis for building the earthly paradise due to His having performed the Reordering Works of the Universe (Cheonjigongsa) for nine years. The work that remains will be completed year by year following the cosmic program that Sangje set for the universe. The chapters titled 'Gyoun (Progress of the Order)' in Jeon-gyeong (The Canonical Scripture) can be summarized into three parts: Viewing Gyoun, Spreading Gyoun, and Establishing the firm ground of Gyoun. Viewing Gyoun is seeing how the teachings would be transmitted from the beginning to end. The work of Gyoun was established by Sangje and promoted as the teachings of Sangje which will ultimately unfold into the realization of an earthly paradise. Spreading Gyoun is performed by disciples who received the teachings from Sangje and then the successor to whom Sangje transmitted the religious authority. Since chapter two of Gyoun is about the hagiography of Doju Jo Jeongsan, it is shown that Doju unfolded and developed Sangje's teachings. Establishing the firm ground of Gyoun is carried out to enable practitioners to understand that Dotong-gunja ('Dao-Empowered Sages,' Earthly Immortals) will be produced as a result of Sangje's Reordering Works of Heaven and Earth and that humans can perfect themselves through cultivating the Dao. In conclusion, Gyoun can be summarized as a process that started during Doju Jo Jeongsan's 50 years (1909~1958) of holy works and spreading of the teachings. Next, it was continued through the time of Dojeon who was bestowed with religious authority through Doju's last words. Dojeon, like Doju before him, spread the teachings. In later times, there will be Dotong-gunjas who transmit Sangje's teachings to the whole world. Although the above characterizations are accurate, I compared some verses from Chapter 1 of Progress of the Order (Gyoun) in The Canonical Scripture (Jeon-gyeong) of Daesoon Jinrihoe to the 6 th edition (1965) of Daesoon Jeongyeong, a key scripture from the earliest strata of Jeungsanist scriptures, and found that there were a few earlier variations of the same content. The use of words and sentences were different though in several of these verses. Also, some of the verses indicated alternative historical dates (years), and some of the verses from Chapter 1 of Progress of the Order from The Canonical Scripture do not appear anywhere in the 6th edition of Daesoon Jeong-gyeong.

A Comparative Study on Outspreading Virtues and Enlightenment Teaching Related to Daesoon Thought and Shinnyo Thought (대순사상과 진여사상의 포덕과 교화에 관한 비교연구)

  • Kim, Yong-hwan
    • Journal of the Daesoon Academy of Sciences
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    • v.25_1
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    • pp.121-155
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    • 2015
  • The purpose of this article is to study on the comparative relationship between mutual cooperation of the Dae-soon thought of Dae-soon jinrihoe and Shinnyo thought of Shinjo Ito. Dae-soon thought focuses on outspreading virtues and enlightenment teaching based on the saying of Jeong-san Sang Jae's Mutual cooperation without any grudge. According to the Buddha's nature thought of Shinjo Ito, 'Dharma kāya resident' is the source of touching upon buddhahood. The Shinyo-en is an outward manifestation of their deep resolve to help others by cultivating spiritual faculty and mind session. First, we can find the virtue action theory in the mutual cooperation of Dae-soon thought and the virtue nature theory in the Shinnyo thought of Shinjo Ito. From the perspective of comparative relationship, it was Jeong-san Sang Jae who laid foundation for the Posterior Grand Renewal. His idea is that the universe should be completed through the mutual communication between the earth and men following the Posterior Grand Renewal. It was Kyodoin-sama who laid the foundation for identifying the place Shinchoji was established. It was at the time that the power we call bakku-daiju as transversality and Shinnyo spiritual faculty were perfected through Shindoin-sama's passing. Second, based on Jeon-kyungn or Dae-soon Ji Chim, outspreading virtue is to awaken mutual cooperation without any grudge and the enlightenment teaching to practice according to mutual cooperation principle without any deceit toward one's own self. No deceit toward one's own self is to be sincere, to be respectful and to be faithful in Jeong-san Sang Jae. In the different context of Mahayana Buddhism, we can be aware that the immortal resident immortal of Dharma kāya is the source of permanent bliss in the Mahāyāna Mahāparinirvāṇa Sūtra' From the perspective of comparative relationship to pray toward Jeong-san Sang Jae and to participate in the Posterior Grand Renewal is to take part in Cheonji-Gongsa. It is a similar phenomena to be reflected suchness reality before the three personifications of buddhahood and the Shinnyo Stupa is the same meaning as meeting the ever present Buddha. Both of them, they focus to find religious altruism from real possibilities of mutual support. They argue that to dispense with altruism is to dispense with Sang Jae or Dharma for the divine transformation of human possibilities Third, Everybody possesses unique and wonderful abilities to be unified with Jeong-san Sang Jae. If we seek happiness by trying to get by without making much of an effort to take part in CheonjiGongsa, it will be difficult to attain the harmony and peace of mankind with outspreading virtues and enlightenment teaching. In the 'Mahāyāna Mahāparinirvāṇa Sūtra' tells us 'all sentient beings have Buddha nature' that could be the possibility to the fulfillment of buddhahood in the spiritual practice. From the comparative relationship, we can strive with open hearts and minds, in efforts that benefit others, and in ways we can work together to build a word of joy in which everyone can have an opportunity to cultivate spiritual faculty. This is based on mutually beneficial voluntary focused our principles into practice the spirit to build a mind session of Shinnyo as the civic clean precepts of 'Mahāyāna Mahāparinirvāṇa Sūtra'. Fourth, the disciples of Jeong-san Sang Jae are encouraged to acquire the Mutual cooperation manner of being considerate. It is important to accumulate virtue action by daily effort. It is the contrast to awaken virtue nature by daily practice. The Buddha's nature thought of Shinjo Ito is based on the thought of Mahāyāna Mahāparinirvāṇa Sūtra. It can be supported by the Shinnyo parents and the two Dojis to build a world of joy as the light dharma descending and the emphasis of Tathatā spiritual faculty. It's not that we can't do something we haven't attained a higher spiritual level. What counts is our continuos effort, act so we can cultivate our spiritual faculty through the way of mind session.

The Rusticity and Spirit of Scholars Found at Suwoojae, the Birth House of Garam Byungi Lee (가람(嘉藍) 이병기 생가(李秉岐 生家) 수우재(守愚齋)에서 찾는 소박함과 선비정신)

  • Kim, Jung-Sik;Rho, Jae-Hyun;Kim, Jeong-Moon;Oh, Hyun-Kyung
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.28 no.1
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    • pp.1-11
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    • 2010
  • This study examines the authentic meaning, location, garden layout, and structural characteristics of Suwoojae(守愚齋), the birth house of Garam Byungi Lee, which was the very epitome of the traditional house structure based on literature review, field survey, and the existing measured drawings. The followings explain how rusticity and spirit of scholars, the core concepts of Garam's poetry, were featured in structural and spacial arrangements of Suwoojae as well as its location and physical layout. 1. Suwoojae is enclosed by Cheonho mountain which fans out of Noryoung mountains in East and located on the tail of Yongwha mountain in West. It has proved to be Yangtack Myoungdang according to the Poongsoo theory, Inguljiryoungron; The energy of earth at a certain location results in the better fortune together with the energy emitted from human body. 2. Suwoojae is an official local monument which was built in 1844, late Joesoen Dynasty by Joheung Lee, Garam's grandfather. Some parts of inner-structure connect with the kitchen in the shape of called Gopae. Suwoojae consists of 4 Sarangchae, 3 Gobangchae, and a Jangdokdae behind Anchae. 3. Since inner and outer walls of Suwoojae are distinctly separate from the main structure, its look varies significantly from different angles. Suwoojae, in its entirety, discloses Garam's philosophy, ideas, and ideology on life and the universe. 4. Apricot trees, Japanese-magnolias, aromatic-trees, crape myrtle, white-magnolias, camellia-trees were planted on the left of the walls, and persimmon trees, jujube trees, plum trees, quince trees were at the inner-yard. Especially, trifoliate orange trees a natural monument of Jeonrabukdo draw substantial attention from visitors. 5. The main garden facilities are located in front of Sarangchae: A rectangle pond(14.72m in length and 3.87m in height), the surroundings of the pond and Anchae, rocks that have distinctive shapes. In general, the garden was designed to incorporate the scenery around Suwoojae as a part of its structure and contain the love for nature and aesthetic sense. 6. It seems that the natural surroundings of Suwoojae had helped form motives of Garam's poetry and assisted him in finding subject-matters and identifying the themes of his works. This is well revealed in his poem, Seungwoonjungee.

A Study on the Gwon Ji (權智) of Jeon-gyeong (『전경(典經)』 「권지(權智)」편 연구)

  • Ko, Nam-sik
    • Journal of the Daesoon Academy of Sciences
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    • v.37
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    • pp.53-105
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    • 2021
  • The purpose of this study is to clarify the meaning of Gwonji (權智, Authority and Foreknowledge) through the phrases contained in the section, Gwonji of the Jeon-gyeong (known in English as The Canonical Scripture), and to compare the changes that each verse from Gwonji underwent by juxtaposing it against the sixth edition of Daesoon Jeong-gyeong (which was published prior to the Jeon-gyeong) to explore the term's literary meaning. In order to save the world, Sangje descended to human world and performed the Cheonjigongsa (Reordering Works of the Universe) for nine years with the power he exercises over the Three Realms of Heaven, Earth, and Humanity. Based on the plan set by the Cheonjigongsa, Sangje's teachings were spread to humanity and provided as the basis for building the earthly paradise. From this perspective, this study demonstrates its significance by providing a comprehensive approach to the Jeon-gyeong by highlighting the subject of Sangje's authority and wisdom as recorded in the section titled Gwonji. There is also value in the variant verses from Gwonji that the study discovered by comparing and analyzing the phrases from chapters one and two of Gwonji as they appear in the Jeon-gyeong with their equivalents from the sixth edition of Daesoon Jeong-gyeong, which was published in 1965, nearly a decade before Daesoon Jinrihoe's publication of the Jeon-gyeong in 1974. The results of this comparative study of parallel passages related to Gwonji are as follows: First, Gwonji can be understood as the authority and wisdom of Sangje, and this is the core element in realizing the Earthly Paradise through His Cheonjigongsa. Second, phrases related to Sangje's authority and wisdom are spread out in the seven sections of the Jeon-gyeong, and they were written to emphasize the main purpose suggested in each section or chapter. Third, in sections other than Gwonji, the great power of Sangje is exercised to treat matters related to deities and social problems, whereas in Gwonji part, it is dedicated to the performance of Cheonjigongsa. Fourth, there are five sections of the Jeon-gyeong which are organized into chapters. All of these sections and their chapters indicate the year when key events transpired. Fifth, when passages from chapter one of Gwonji is compared to parallel passages from Daesoon Jeon-gyeong, there are several verses that vary in terms of their wording and also sentences that indicate a different dates or times for certain events.

IMAGING SIMULATIONS FOR THE KOREAN VLBI NETWORK(KVN) (한국우주전파관측망(KVN)의 영상모의실험)

  • Jung, Tae-Hyun;Rhee, Myung-Hyun;Roh, Duk-Gyoo;Kim, Hyun-Goo;Sohn, Bong-Won
    • Journal of Astronomy and Space Sciences
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    • v.22 no.1
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    • pp.1-12
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    • 2005
  • The Korean VLBI Network (KVN) will open a new field of research in astronomy, geodesy and earth science using the newest three Elm radio telescopes. This will expand our ability to look at the Universe in the millimeter regime. Imaging capability of radio interferometry is highly dependent upon the antenna configuration, source size, declination and the shape of target. In this paper, imaging simulations are carried out with the KVN system configuration. Five test images were used which were a point source, multi-point sources, a uniform sphere with two different sizes compared to the synthesis beam of the KVN and a Very Large Array (VLA) image of Cygnus A. The declination for the full time simulation was set as +60 degrees and the observation time range was -6 to +6 hours around transit. Simulations have been done at 22GHz, one of the KVN observation frequency. All these simulations and data reductions have been run with the Astronomical Image Processing System (AIPS) software package. As the KVN array has a resolution of about 6 mas (milli arcsecond) at 220Hz, in case of model source being approximately the beam size or smaller, the ratio of peak intensity over RMS shows about 10000:1 and 5000:1. The other case in which model source is larger than the beam size, this ratio shows very low range of about 115:1 and 34:1. This is due to the lack of short baselines and the small number of antenna. We compare the coordinates of the model images with those of the cleaned images. The result shows mostly perfect correspondence except in the case of the 12mas uniform sphere. Therefore, the main astronomical targets for the KVN will be the compact sources and the KVN will have an excellent performance in the astrometry for these sources.

A Study on the twelve earthly branches' Yin Yang, Five elements, Six Qi, viscera combination, Mutual collision and Mutual combination. (십이지지(十二地支)의 음양(陰陽) 오행(五行) 육기(六氣) 장부(臟腑)의 배합(配合) 및 상충(相沖) 상합(相合)에 관한(關) 연구(硏究))

  • Kim, hung Joo;Jeon, yun ju;Yun, Chang-Yeol
    • Journal of Haehwa Medicine
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    • v.27 no.1
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    • pp.9-20
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    • 2018
  • Objectives : Ten heavenly stems(10天干) and Twelve earthly branches(12地支) are symbols exposing change order in heaven and earth, and are a very important sign in studying oriental philosophy and oriental medicine. Especially, 10 heavenly stems(10天干) and 12 earthly branches(12地支) are indispensable for the study of Five Circuits And Six Qi(오운육기), and a deep study is needed. Methods : I have examined Yin Yang combination(음양배합), Five elements combination(오행배합), Six Qi 3Yin 3Yang combination(육기삼음삼양배합), viscera combination(장부배합), Mutual collision(상충), Six combination(육합), Three combination(삼합), etc. of 12 earthly branches(12지지) by referring to books such as "Yellow Emperor Internal Classic" ("黃帝內經") and "Principle of universe change" ("우주변화의 원리"). Results & Conclusions : Zi Yin Chen Wu Shen Xu(子 寅 辰 午 申 戌) become Yang(陽), Chou Mao Si Wei You Hai(丑 卯 巳 未 酉 亥) become Yin(陰), Zi Si Yin Mao Chen Si(子 丑 寅 卯 辰 巳) become Yang, and Wu Wei Shen You Xu Hai(午 未 申 酉 戌 亥) become Yin. Twelve earthly branches can be divided into five movements by its original meaning, where YinMao(인묘) is tree, SiWu(사오) is a fire, ShenYou(신유) is a gold, HaiZi(해자) is water, and ChenXuChouWei(진술축미) mediate in the middle of four movements So they become soil(土). SiHai(巳亥) is JueYin Wind Tree(궐음 풍목), ZiWu(子午) is ShaoYin Monarch Fire(소음 군화), ChouWei(丑未) is TaiYin Humid Soil(태음 습토), YinShen(寅申) is ShaoYang Ministerial Fire(소양 상화), MaoYou(卯酉) is YangMing Dry Gold(양명 조금), and ChenXu(辰戌) is TaiYang Cold Water(태양 한수). Viscera combination(장부배합) combines Zi(子) and Bile(膽), Chou(丑) and Liver(肝), Yin(寅) and Lung(肺), Mao(卯) and Large intestine(大腸), Chen(辰) and Stomach(胃), Si(巳) and Spleen(脾), Wu(午) and Heart(心), Wei(未) and Small intestine(小腸), Shen(申) and Bladder(膀胱), You(酉) and Kidney(腎), Xu(戌) and Pericardium(心包), Hai(亥) and Tri-energizer(三焦), Which means that the function of the viscera and channels is the most active at that time. Twelve earthly branches mutual collisions collide with Zi(子) and Wu(午), Chou(丑) and Wei(未), Yin(寅) and Shen(申), Mao(卯) and You(酉), Chen(辰) and Xu(戌), and Si(巳) and Hai(亥). The two colliding earthly branches are on opposite sides, facing each other and restricting each other by the relation of Yin-Yin and Yang-Yang it rejects each other so a collision occurs. Six Correspondences(六合) coincide with Zi(子) and Chou(丑), Yin(寅) and Hai (亥), Mao(卯) and Xu(戌), Chen(辰) and You(酉) and Si(巳) and Shen(申) Wu(午) and Wei(未). Three combination(三合) is composed of ShenZiChen(申子辰), SiYouChou(巳酉丑), YinWuXu(寅午戌), and HaiMaoWei(亥卯未). Three combination(三合) is composed of ShenZiChen(申子辰), SiYouChou(巳酉丑), YinWuXu(寅午戌), and HaiMaoWei(亥卯未). This is because the time Six Qi(六氣) shifts in these three years are the same.

『Chūn-qiū』Wáng-lì(『春秋』王曆)➂ - from Zhōu-lì(周曆) to Xià-lì(夏曆), and "Xíng-xià-zhī-shí(行夏之時)" Mentioned by Confucius (『춘추』 왕력(王曆)➂ - 주력(周曆)에서 하력(夏曆)으로, 그리고 공자의 "행하지시(行夏之時)")

  • Seo, Jeong-Hwa
    • The Journal of Korean Philosophical History
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    • no.54
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    • pp.153-184
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    • 2017
  • During the Pre-Qin(秦) Dynasty era, there were the records that there had been many calendar systems, such as $g{\check{u}}-li{\grave{u}}-l{\grave{i}}$(古六曆 : six ancient calendar systems). Then, the fact that particularly $zh{\bar{o}}u-l{\grave{i}}$(周曆) and $xi{\grave{a}}-l{\grave{i}}$(夏曆) were mainly discussed among them resulted from a lot of discussions from the differences in the calendar system in "$Ch{\bar{u}}n-qi{\bar{u}}$(春秋)" known to have been written by Confucius from the calendar system in "$X{\acute{i}}ng-xi{\grave{a}}-zh{\bar{i}}-sh{\acute{i}}$(行夏之時 : implement the calendar of Ha dynasty.)" that Confucius mentioned himself to his disciple. $zh{\bar{o}}u-l{\grave{i}}$(周曆) with $d{\bar{o}}ngzh{\grave{i}}-yu{\grave{e}}$(冬至月 : the 11th month of the lunar calendar) as the first month of a year had the system of the lunar calendar, and $xi{\grave{a}}-l{\grave{i}}$(夏曆) called as the calendar of Ha(夏) dynasty had the system of $ji{\acute{e}}-q{\grave{i}}-l{\grave{i}}$(節氣曆 : a kind of the solar calendar that divides one year of 365 days into 24 solar terms) with $y{\acute{i}}n-yu{\grave{e}}$(寅月 :one month from the present Feb 5) as the first month of a year. These two calendars had definite differences in the first months of a year, names of seasons, and the lunar calendar and the solar calendar. The fundamental reason why Confucius recommended the performance of $xi{\grave{a}}-l{\grave{i}}$(夏曆) as a way to run the nation was not that it started from the philosophical view of the universe that among the 'three $zh{\bar{e}}ng$'(三正)' of $ti{\bar{a}}n-zh{\bar{e}}ng$(天正 : the first month of a year with the heaven as the standard), $d{\grave{i}}-zh{\bar{e}}ng$(地正 : the first month of a year with the earth as the standard) and $r{\acute{e}}n-zh{\bar{e}}ng$(人正 : the first month of a year with humans as the standard), but that he wanted to emphasize the importance of practical national economic policies to enhance agricultural productivity. It becomes the criterion that even though Confucius emphasized that politicians should not have moral flaws ideally, with regard to public policies, he wanted to stress politicians' duties based on the reality a lot.