• Title/Summary/Keyword: Man's Will

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Application of geophysical exploration methods for safety diagnosis of the basement of stone pagoda (지구물리탐사 방법의 석탑지반 안전진단에의 적용)

  • Suh, Man-Cheol;Oh, Jin-Yong;Kim, Ki-Hyun
    • 한국지구물리탐사학회:학술대회논문집
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    • 2004.08a
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    • pp.70-83
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    • 2004
  • The safety diagnosis of cultural assets is Primarily focused on its non-destructiveness. Research on the nondestructive diagnosis and conservation of masonry cultural heritage is the key which is considered by technologic kernel. Geophyscial Prospecting as nondestructive diagnostic technology plays an important role in the characterization of the foundation of stone pagodas. It is natural that understanding of shallow subsurface condition beneath them is essential for their structural safety diagnosis. As an example, the nondestructive geophysical methods were applied to two three-story stone pagodas, Seokgatap (height 10.8 m, width 4.4 m, weight 82.3 ton) and Dabotap (height 10.4 m, width 7.4 m, weight 123.2 ton) which were built in 791 at Bulkuksa temple. An earlier archaeological investigation shows that stone pagodas have experienced severe weathering process and are slightly leaning, which will threaten their stability At the base part of Dabotap, an offset of the stone alignment is also observed. Direct measurements of ultrasonic velocities was introduced for the mechanical properties of the stone The velocity ranges of ultrasonic waves for Dabotap and Seokgatap are 1217${\~}$4403 m/s and 584${\~}$5845 m/s, respectively, and the estimated averages of the uniaxial compressive strength are 463 kg/$cm^2$ and 409 kg/$cm^2$, respectively. Site characteristics, around the pagodas are determined by the measurement of multiple properties such as seismic velocity, resistivity, image of ground-penetrating radar, On the basis of the higher velocity structure, the site of Seokgatap appears to have solider stability than the Seokgatap site. Near the pagodas, higher(up to 2200 $\Omega$m) resistivity is present whereas their outskirts have as low as 200 $\Omega$m. By the combined results of each geophyscial methods, the subsurface boundaries of two stone pagodas are revealed. The Dabotap site is in the form of an octagon having 6-m-long side with the depth of ${\~}$4 m, whereas the Seokgatap site is the 8 ${\times}$ 10 m rectangle with the depth of 3 m. These subsurface structures appear to reflect the original foundations constructed against the stone load of ${\~}8 ton/m^2$. At the subsurface beneath the northeast of each pagoda, low seismic velocity as well as low resistivity is prominent. It is interpreted to represent the weak underground condition which Is the possible cause of the slightly leaning pagodas toward the NNW.

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Ethanol Extracts of Mori Folium Inhibit Adipogenesis Through Activation of AMPK Signaling Pathway in 3T3-L1 Preadipocytes (3T3-L1 세포에서 상엽이 유발하는 AMPK signaling pathway를 통한 adipogenesis 억제에 관한 연구)

  • Ji, Seon Young;Jeon, Keong Yoon;Jeong, Jin Woo;Hong, Su Hyun;Huh, Man Kyu;Choi, Yung Hyun;Park, Cheol
    • Journal of Life Science
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    • v.27 no.2
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    • pp.155-163
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    • 2017
  • Mori Folium, the leaf of Morus alba, is a traditional medicinal herb that shows various pharmacological activities such as antiinflammatory, antidiabetic, antimelanogenesis, antioxidant, antibacterial, antiallergic, and immunomodulatory activities. However, the mechanisms of their inhibitory effects on adipocyte differentiation and adipogenesis remain poorly understood. In the present study, we investigated the inhibition of adipocyte differentiation and adipogenesis by ethanol extracts of Mori Folium (EEMF) in 3T3-L1 preadipocytes. Treatment with EEMF suppressed the terminal differentiation of 3T3-L1 preadipocytes in a dose-dependent manner, as confirmed by a decrease in the lipid droplet number and lipid content through Oil Red O staining. EEMF significantly reduced the accumulation of cellular triglyceride, which is associated with a significant inhibition of pro-adipogenic transcription factors, including sterol regulatory element-binding protein-1c (SREBP-1c), peroxisome proliferator-activated receptor-${\gamma}$ ($PPAR{\gamma}$), and CCAAT/enhancer-binding proteins ${\alpha}$ ($C/EBP{\alpha}$) and ${\beta}$ ($C/EBP{\beta}$). In addition, EEMF potentially downregulated the expression of adipocyte-specific genes, including adipocyte fatty acid binding protein (aP2) and leptin. Furthermore, EEMF treatment effectively increased the phosphorylation of the AMP-activated protein kinase (AMPK) and acetyl CoA carboxylase (ACC); however, treatment with a potent inhibitor of AMPK, compound C, significantly restored the EEMF-induced inhibition of pro-adipogenic transcription factors and adipocyte-specific genes. These results together indicate that EEMF has preeminent effects on the inhibition of adipogenesis through the AMPK signaling pathway, and further studies will be needed to identify the active compounds in Mori Folium.

The Effect of the Optical Points Difference between Finished-Reading Glasses and Dispensing Reading Glasses (완성품 돋보기와 조제가공된 돋보기가 광학적 요소에 미치는 영향)

  • Shim, Young-Cheol;Yoo, Gun-Chang;Kim, In-Suk
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.3
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    • pp.65-71
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    • 2008
  • Purpose: This paper studied the effect of eyes on the comparison between the distance optical centers problem of dispensing reading glasses made by optician and finished reading glasses in the current market. Methods: The method of this study has been measured by eleven different categories from +1.00D to +4.00D. This study also separated into three groups by their optical frame size and measured optical center point (O.C) and optical center height (O.H) with 200 peoples of man and females over 40 years old without ocular disease living in Gwang-san gu, Gwang-Ju city. Results: As a result, optical center point ranged from 57 mm to 80 mm and it turned to be most common range is from 61 mm to 65 mm (64.6%). Moreover, the optical center height ranged from 1 mm to 8mm and most common ranged (23%) were 4 mm. In other words, finished reading glasses have irregular optical ranges. After observing 200 people who are over 40 years old men and women, result shows that more than 75.5% (151 people) currently use finished reading glasses. Survey of 151 people, most common error between the finished reading glasses's O.C and the wearers P.D were 4 mm (45%). Furthermore, the most common error between the finished reading glassses's O.H and the wearers O.H ranged from 3 mm to 4 mm. Astonishingly, the entire 151 people who wear finished reading glasses appeal that they feel tiredness on their eyes when they wear finished reading glasses. 53 people (35%) claimed that they feel tiredness on their eyes after 10 to 20 minutes wearing finished reading glasses. Base on the research, We conducted more experiment to find the value of prism of optical centers err because it will tell us whether the finished reading glasses are good enough to wear or not. We multiplied diopter by the difference between finished reading glasses's O.C. and wearer's P.D. Consequently, We found out that the finished reading glasses counter to the German RAL-RG 915 policy. And We also found that it is relative to the diopter of lenses. In conclusion, based on the researched that wearing finished reading glasses have a dangerous factor for our vision. Therefore optician must need to recommend correctly made dispensing reading glasses based on the optical center point.

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The Affirmation and Redemption of Life and Übermensch in Nietzsche's Thought (니체에게서 삶의 긍정 및 구원Erlösung과 위버멘쉬Übermensch)

  • Kim, Joo-whee
    • Journal of Korean Philosophical Society
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    • v.131
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    • pp.77-103
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    • 2014
  • It is well known that Nietzsche insists on the affirmation of life, and the subject of 'affirmation of life' is a familiar one in Nietzsche literature. We want to throw an unfamiliar light on this familiar subject, connecting the theme of affirmation with that of redemption, and insisting on the centrality of the theme of redemption in Zarathustra's teaching of ${\ddot{U}}bermensch$. For Nietzsche, the redemption of human life means that its life is endowed with some meaning and its existence is positively justified. With this redemption, an active affirmation of life is possible, which means that we not only endure this life once but also request it for indefinite times. According to Nietzsche, for this kind of redemption and active affirmation we need an ultimate ground of meaning and only the excellence of life, that is, of 'will to power' can serve as this ultimate ground. Accepting the Greek way of identifying virtue with excellence, Nietzsche thought that life can justify itself at the ultimate form of life in ${\ddot{U}}bermensch$. Then, through ${\ddot{U}}bermensch$ the way is opened for man to endow meanings on and justify its life. That is, ${\ddot{U}}bermensch$ is not only the one who affirms its life, but also the very condition in which humanity can justify its life in general. With the goal and ideal of ${\ddot{U}}bermensch$ accepted, the affirmation and redemption of an individual life depends on how it manages to create its own life in relation to this goal and ideal. According to Nietzsche, though we cannot go back to the past, we still can recreate it and change its meanings through working on the future. Only those who try to create a meaningful future and thus recreate the past could redeem and affirm their own lives. That is, for Nietzsche, to affirm and redeem one's life means not just to change one's attitude to life but to create and recreate it with the eye for ${\ddot{U}}bermensch$.

Shalf Life Enhancement of Minimally Processed Fruits and Vegetables

  • Kim, Dong-Man
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 1993.12a
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    • pp.6-9
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    • 1993
  • According to changes in population, economic conditions, life-stile and eating habits, the frui ts and vegetables market wi 11 be shi fted from processed (i. e. , canned) to fresh. Undressed fresh produce, consisting of washed, disinfected and peeled fruits and vegetables that either sliced or grated, are currently increased in demand by retail and institutional market which use them as salad components or in ready-to use foods, Main attributes of minimally processed fruits and vegetables are convenience and fresh-like quality. Minimally processed Products readily deteriorate in quality, especially color and texture, as a result of endogeneous enzyme enhanced respiration and microorganisms which lead to reduced shelf Iife. According to changes in population, economic conditions, life-stile and eating habits, the frui ts and vegetables market wi 11 be shi fted from processed (i. e. , canned) to fresh. Undressed fresh produce, consisting of washed, disinfected and peeled fruits and vegetables that either sliced or grated, are currently increased in demand by retail and institutional market which use them as salad components or in ready-to use foods, Main attributes of minimally processed fruits and vegetables are convenience and fresh-like quality. Minimally processed Products readily deteriorate in quality, especially color and texture, as a result of endogeneous enzyme enhanced respiration and microorganisms which lead to reduced shelf Iife. Thus. to prevent these undesirable changes , val'ious techniques such as controlled atmosphere (CA) storage, modified atmosphere OIA) storage, including vacuum packaging have been receiving considerable attention, Although milch research has been done to find optimal conditions for whole intact frui ts and vegetables, only limi ted information is avai lable on fresh cut. and other minimally processed products. 81 iced frui ts exhibi t increas~d ethylene production and respiration compal'ed to whole f, 'uits during distribution in response to tissue damage. As a result, accelerated senescence and enzymatic browning OCCUI', Recent l'esearch on minimally processed fl'uits and vegetables has mainly focused on methods to inhibit browning, due to ban on use of sulfur dioxide, In order to retard or prevent these physiological changes, val'ious al ternatives, reducing agents. acidulants, chelating agents and inol'ganic sal ts have been evaluated for use on fresh cut fl'ui ts. Al though some agents were effective replacement for sulfur dioxide. consum$\textregistered$I'S demandless use of chemical on such products. Shel~ life of minimally processed products has been extended by inhibition of metabolic reactions associated with loss of quality and by inhibition of aerobic spoilage caused by wide variety of microorganisms. Appl ication of ~I.-\ packaging, including vacuum packaging, retards the rate of respiration, prevents growth of aerobic spoilage organisms, inhibits oxidation and color deterioration. Tissue softening is another major problem in minimally processed products because enzymes re 1 a ted to ce 11 wa 11 degrada t i on are not inactivated. Various treatments have been investigated for retardation of the softening of sliced products. Some studies have concentrated on the application of an active packaging system with ~I, l. packaging and calcium infi 1 tration as possible measures to retain firmness of processed products. In my opinion, one important step for production of minimally processed frui ts wi th favorabl e color of cut surface and firm texture is the selection of better cultivar. As the view, changing tendency of fresh color by apple cultivars and relationship between the tendency and PPO activity will be discussed in the seminar. In addition to the topic, research result on quality enhancement of fresh apple slices by heat shock treatment will be introduced.

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A study on distinctive view of Cheng I's the sage-theory (정이(程?) 성인론(聖人論)의 특징에 관한 고찰)

  • Kim, Sang-Rae
    • The Journal of Korean Philosophical History
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    • no.56
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    • pp.151-180
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    • 2018
  • Since the completion of the theories on human ethics and moral had been established to pursue by Confucian thinkers like Confucius and Mencius, they generally had agreed to present the basic principles for human education which every human could be the sage. In these principles for human ethics and morality there is on the premise that the knowledge about your own ethical and that the completion of the so-called act(爲) and learning(學). They had given to us that how to get a goal for the ethical and moral lives there are several academic oriented methodology will have act and learning set. In the point of achieving complete figures which act and learning for good society, there was named the sage(聖). This concept sage has two major types. One is on for the political figures that completed, and the other one is for the realm of academic side. Confucian as above mentioned the moral human being is equipped with a complete personality and political ability to make man and society perfect. Confucius has been understood as a complete human being. Yes, ideal for these two types of figures will be fulfilled in some way? They take a mystical ability to a priori or a posteriori, such as human effort can reach the sage. There are many thinkers are obvious and logical answer for this major problem in the system of confucian philosophy I have been trying. About the sage(聖), inherently natural learning(生知) occur to the position sage or knowledge (學知), can lead to there are two of the doctrine for that problem. With the study of learning and knowledge on human beings and real society the two systems concerned together. In fact, the main content of the "Analects of Confucius" we have a set of ethical and moral values not the benevolent conversation about Jin(仁) and his disciples a steady emphasis but on in praise of learning (學) for. However, at the time in Han Tang(漢唐) Han Wi(韓愈) and Wang Chung(王充), according to such thinkers the sage is already a priori determined, cannot be reached by human effort. But At the beginning of the Neo-Confucianism, Cheng I(程?) for the pioneer this Song(宋) scholars, regarding this issue could rebirth the thought that every human could be the sage through the learning as the pre-Chin(先秦) times.

A Perspective of Analytical Psychology on 'Yeondo', a Prayer for Souls in Purgatory of Korean Catholic Church (한국 천주교 '연도(煉禱)'의 분석심리학적 고찰)

  • Chun Ja Yeo
    • Sim-seong Yeon-gu
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    • v.31 no.1
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    • pp.1-40
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    • 2016
  • This thesis is a study on the symbolism of 'Yeondo', a prayer for the souls in purgatory of Korean Catholic Church as a 'psychic container' for the spiritual transformation in the psyche from a perspective of analytical psychology. Yeondo' could be the 'rites of passage' of the last judgement for the souls in purgatory which is in between the heaven and the hell. And both the bereaved and the dead go through the stages of separation, transition and incorporation which are the schema of the 'rites of passage'. In particular, they have a special sense of solidarity at the stage of transition, a middle state. The symbolic process of 'Yeondo' is a spiritual transformation of recovery of paradise which could access by the confusion of death, purification and the rebirth. A spiritual reborn process of death and rebirth takes place by contacting the collective unconscious. In 'Yeondo', the death is not the end of life but the beginning of the eternal life. The confusion and disintegration caused by death can be purified and start incorporating. The rites of a paradise recovery has the meaning of trying constantly for the recovery of a wholeness. Praying for the blessing of God and a help from saints in paradise for the sake of the dead means to require conscious cooperation for the Self-realization. Integrating and recognizing unconscious also means something beyond the conscious. The blessed souls in purgatory recovers the paradise experiencing specific purifying process heading towards Self. Going into the center, abyss of unconscious will be recognized as an absolute part of oneself. One becomes the inner man, the transformed personality who is reached by the path of self-knowledge, the kingdom of heaven within oneself and can have the transpersonal energy, which enables to access to God's world and union with God. All desire and the will become one with God. In the final analysis, praying for the blessing of God and a help from saints in paradise for the sake of the dead becomes the path for the more and more conscious expansion of the alive. Therefore, 'Yeondo' as an initiation is the individuation process of the alive and the dead to reflect on themselves.

A bibliographic study on medical science ancient period (上古時代) and the era of the old-Korea (古朝鮮時代) (상고시대(上古時代)와 고조선시대(古朝鮮時代)의 의학(醫學)에 관(關)한 문헌적(文獻的) 고찰(考察))

  • Kwon, Hak Cheol;Park, Chan-Guk
    • Journal of Korean Medical classics
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    • v.3
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    • pp.218-247
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    • 1989
  • As mentioned above, I got the next conclusion since I had considered the medical contents of the ancient period(上古時代) and the era of the old-Korea(古朝鮮時代) through several bibliographic records. 1. There were Pung-baeg(風伯), Uh-sa(雨師), Un-sa(雲師) that were the names of the governmental officials during the ancient period of Whan-ung(桓雄). Among them, Uh-sa specially managed the treatment for diseases. When we think of the significance of Pung(風)-which means the winds, Uh(雨)-which means the rain, Un(雲)-which means of clouds, we will find out that the human life will be affected by all kinds of phenomena of the nature. So I can infer that ancestries could prevent and treat diseases with adjusting them tn the changes in the weather. 2. There were five government officials(五事) in the ancient period of Whan-ung(桓雄上古時代). They are Uh-ga(牛加), Ma-ga(馬加), Ku-ga(狗加), Cheo-ga(猪加) and Yang-ga(羊加), and had charges of five important duties. Among them, Cheo-ga was set to a charge of treatment for diseases. So we can notice that there existed people who treated for diseases professionally. When we think of the meanings of Uh(牛)-which intends cows or bulls. Ma(馬)-which intends horses, Ku(狗)-which intends dogs, Cheo(猪)-which intends wild boars and Yang(羊)-which intends sheep, we can see that livestocks would be raised at that time, and they came to have more chances to digest meat. Since the digestion of meat became to be a burden on the stomach and the intestines, it might cause a lot of indigestive troubles. 3. When I compared Tan-gun Pal-ga(檀君八加) with the Oh-ga(五加) in the ancient period of Whan-ung(桓雄上古時代), I could tell that the community of Tan-gun's period is more advanced and specialized than one of Whan-ung's. When I think of the next sentence ; "The Prince Imperial, Bu-u(夫虞) become to be a Ro-ga(鷺加), who treat for diseases professionally.", I am sure that the treatment for diseases was more importment than any other things, because he was the third son of Tan-gun(檀君). 4. According to Tan-gun(檀君) mythology, Whan-ung(桓雄) came down from the heaven of the pure Yang(純陽) to the earth and then changed into a man who had had more Yang(陽) than Yin(陰). And a bear came up from the underground(or the cave) to the ground and then changed into a women who had had more Yin(陰) than Yang(陽). So both of them became to hold together. This story implicated that ancestors had taken a serious view of each of them, namely the ancestors didn't give the ascendance to the one side of them, and made much account of the mutual harmony. So I am sure that this fact coincided with the basic theories of oriental medical science. To refer to two proverbs of Tan-gun mythology that are "Ki-Sam-Chil-Il(忌三七日)" which means caring for twenty one days, and "Pul-Gyon-Il-Gwang-Baeg-Il(不見日光百日)" which means keeping indoors for one hundred days, I can tell you that "twenty-one-day" involves the principle of the birth of life, and "one-hundred-day" contains a preparatory period or the period of death to bear another life. 5. From the medical stuff, such as wormwood(艾), garlic(蒜), or wonder-working herbage(靈草), that had been written at the bibliographic papers of the ancient period(上古時代) and the era of the old-Korea(古朝鮮時代), I consider that many people might get a lot of women's diseases, indigestive troubles, and other diseases that were caused by the weakness, but with using various spices, such as the leaves of water pepper(蔘), they could prevent the occurrance of all kinds of diseases previously. So I regard this treatment as the medicine from food. 6. One of the sayings at Nae-gyong(內經) is that "The stone accupuncture(砭石) came from the orient." We can see both "wonder-wor-king wormwood(靈草)" and "dried wormwood(乾艾)" in the several bibliographic papers of the ancient history of the old-Korea(朝鮮上古史). From these records, I can be convinced that ancestors would utilize the acupuncture(針) and the moxa cautery(灸) to cure a patient of a disease. 7. Even though someone claimed that the book, "medical science and chemistry(醫學化學)" and "medical treatment(醫學大方)" had had been written during the ancient period of the old-Korea(上古朝鮮時代), such a fact can't have been ascertained historical evidence. But it has been handed down that there existed the original phonetic alphabet, such as the "Ka-Im-To alphabet(加臨土文字)" at that time. The terms about the diseases, which had been occurred at the community of the old-Korea(古朝鮮地域), were recorded fragmentarily at other records after that time. The origin of confucianism came from the race of the eastern barbarians, and Tae-Ho-Pok-Hi(太嗅伏義) and the king. Sun(舜) came from the eastern barbarians, too. The divination of tortoise shells at the country of Un(殷) is another from which was developed at the eastern barbarians' fortune-telling of animal bones. From these facts, I can infer that, by all means, they might record the medical knowledge which had been stored for thousands of years while contacting with china directly.

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Documentation of Intangible Cultural Heritage Using Motion Capture Technology Focusing on the documentation of Seungmu, Salpuri and Taepyeongmu (부록 3. 모션캡쳐를 이용한 무형문화재의 기록작성 - 국가지정 중요무형문화재 승무·살풀이·태평무를 중심으로 -)

  • Park, Weonmo;Go, Jungil;Kim, Yongsuk
    • Korean Journal of Heritage: History & Science
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    • v.39
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    • pp.351-378
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    • 2006
  • With the development of media, the methods for the documentation of intangible cultural heritage have been also developed and diversified. As well as the previous analogue ways of documentation, the have been recently applying new multi-media technologies focusing on digital pictures, sound sources, movies, etc. Among the new technologies, the documentation of intangible cultural heritage using the method of 'Motion Capture' has proved itself prominent especially in the fields that require three-dimensional documentation such as dances and performances. Motion Capture refers to the documentation technology which records the signals of the time varing positions derived from the sensors equipped on the surface of an object. It converts the signals from the sensors into digital data which can be plotted as points on the virtual coordinates of the computer and records the movement of the points during a certain period of time, as the object moves. It produces scientific data for the preservation of intangible cultural heritage, by displaying digital data which represents the virtual motion of a holder of an intangible cultural heritage. National Research Institute of Cultural Properties (NRICP) has been working on for the development of new documentation method for the Important Intangible Cultural Heritage designated by Korean government. This is to be done using 'motion capture' equipments which are also widely used for the computer graphics in movie or game industries. This project is designed to apply the motion capture technology for 3 years- from 2005 to 2007 - for 11 performances from 7 traditional dances of which body gestures have considerable values among the Important Intangible Cultural Heritage performances. This is to be supported by lottery funds. In 2005, the first year of the project, accumulated were data of single dances, such as Seungmu (monk's dance), Salpuri(a solo dance for spiritual cleansing dance), Taepyeongmu (dance of peace), which are relatively easy in terms of performing skills. In 2006, group dances, such as Jinju Geommu (Jinju sword dance), Seungjeonmu (dance for victory), Cheoyongmu (dance of Lord Cheoyong), etc., will be documented. In the last year of the project, 2007, education programme for comparative studies, analysis and transmission of intangible cultural heritage and three-dimensional contents for public service will be devised, based on the accumulated data, as well as the documentation of Hakyeonhwadae Habseolmu (crane dance combined with the lotus blossom dance). By describing the processes and results of motion capture documentation of Salpuri dance (Lee Mae-bang), Taepyeongmu (Kang seon-young) and Seungmu (Lee Mae-bang, Lee Ae-ju and Jung Jae-man) conducted in 2005, this report introduces a new approach for the documentation of intangible cultural heritage. During the first year of the project, two questions have been raised. First, how can we capture motions of a holder (dancer) without cutoffs during quite a long performance? After many times of tests, the motion capture system proved itself stable with continuous results. Second, how can we reproduce the accurate motion without the re-targeting process? The project re-created the most accurate motion of the dancer's gestures, applying the new technology to drew out the shape of the dancers's body digital data before the motion capture process for the first time in Korea. The accurate three-dimensional body models for four holders obtained by the body scanning enhanced the accuracy of the motion capture of the dance.

Breeding Site Characteristics of Styan's Grasshopper Warblers(Locustella pleskei) on Mara Islet, Jeju Province, Korea (마라도에 번식하는 섬개개비의 번식지 특성)

  • Kim, Eun-Mi;Kim, Hwa-Jeong;Choi, Chang-Yong;Kang, Chang-Wan;Kang, Hee-Man;Park, Chan-Ryul
    • Korean Journal of Environment and Ecology
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    • v.23 no.6
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    • pp.528-534
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    • 2009
  • Styan's Grasshopper Warblers (Locustella pleskei) are vulnerable species distributed in East-Asia only. Its known breeding sites in Korea are remote islets including Hongdo Islet, Chilbal Islet, Mara Islet, and Chuja Islets, and, therefore, the breeding biology of this species is still poorly known. This study was conducted on Mara Islet (N $33^{\circ}$ 06', E $126^{\circ}$ 16') from May to September 2008 to investigate the breeding status and breeding site characteristics of the grasshopper warblers. A total of 11 breeding pairs and their nests were found on trees and shrubs at artificially planted forests and hedges of Pinus thunbergii. The grasshopper warblers preferentially utilized the shrub trees for nesting places, and major nesting trees were Camellia japonica, Pittosporum tobira and Pinus thunbergii as nesting trees. Average heights of nesting trees and nests were $2.77{\pm}1.10m$ and $1.75{\pm}0.56m$, respectively. The grasshopper warblers selected lower shrubs and trees for nesting than randomly selected ones around them, probably to avoid strong and prevailed winds in flat and un vegetated environments on Mara Islet. The shape of nests was a round bowl-type, and measurements of nests were $11.9{\pm}0.5cm$ in exterior nest diameter, $11.1{\pm}1.1cm$ in height of exterior nest, $5.8{\pm}0.4cm$ in interior nest depth, and 6.0cm in interior nest diameter. It incubated eggs until the early August on Mara islet, and incubation periods of Mara Islet was possibly later than that of other areas. Furthermore, the clutch size in the study area was three, and they laid smaller number of eggs than normal clutch size (4~5 eggs) reported in other areas. Although we could not observe any nest predator on this species in the study area, selective cutting and pruning of trees will diminish dense shrub layer of forests. Therefore, it may affect the breeding of this threatened species which prefers dense shrubs of artificially planted forest of Pinus thunbergii. This study suggests that detailed and consistent further research on breeding biology and habitats of the grasshopper warblers are needed to conserve and manage of Pinus thunbergii forests on Mara Islet as an important breeding site of Styan's Grasshopper Warblers.