• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.4
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• pp.357-365
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• 2016

We observed the ${\gamma}-ray$ shielding characteristics and compressive strength of five types of concrete using general aggregates and high-weight aggregates. The aggregates were classified into fine aggregate and coarse aggregate according to the average size. The experimental results obtained an attenuation coefficient of $0.371cm^{-1}$ from a concrete with the oxidizing slag sand (OSS) and oxidizing slag gravel (OSG) for a ${\gamma}-ray$ of $^{137}Cs$, which is improved by 2% compared with a concrete with typical aggregates of sand and gravel. In the unit weight measurement, a concrete prepared by iron ore sand (IOS) and OSG had the highest value of $3,175kg{\cdot}m^{-3}$. Although the unit weight of the concrete with OSS and OSG was $3,052kg{\cdot}m^{-3}$, which was lower than the maximum unit weight condition by $123kg{\cdot}m^{-3}$, its attenuation coefficient was improved by $0.012cm^{-1}$. The results of chemical analysis of aggregates revealed that the magnesium content in oxidizing slag was lower than that in iron ore, while the calcium content was higher. The concrete with oxidizing slag aggregates demonstrated enhanced ${\gamma}-ray$ shielding performance due to a relatively high calcium content compared with the concrete with OSS and OSG in spite of a low unit weight. All sample concretes mixed with high-weight aggregates had higher compressive strength than the concrete with typical sand and gravel. When OSS and IOS were used, the highest compressive strength was 50.2 MPa, which was an improvement by 45% over general concrete, which was achieved after four weeks of curing.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2003.07b
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• pp.67-88
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• 2003

The consumption of poultry meat (chicken and turkey) grew the most during the past few decades due to several contributing factors such as low price. product research and development. favorable meat characteristics, responsive to consumer needs, vertical integration and industry consolidation, new processing equipments and technology, and aggressive marketing. The major processing technologies developed and used in chicken processing include forming/restructuring, tumbling, curing, smoking, massaging, injection, marination, emulsifying, breading, battering, shredding, dicing, and individual quick freezing. These processing technologies were applied to various parts of chicken including whole carcass. Product developments using breast, thigh, and mechanically separated chicken meat greatly increased the utilization of poultry meat. Chicken breast became the symbol of healthy food, which made chicken meat as the most frequent menu items in restaurants. However, the use of and product development for dark meat, which includes thigh, drum, and chicken wings were rather limited due to comparatively high fat content in dark meat. Majority of chicken are currently sold as further processed ready-to-cook or ready-to-eat forms. Major quality issues in chicken meat include pink color problems in uncured cooked breast, lipid oxidation and off-flavor, tenderness PSE breast, and food safety. Research and development to ensure the safety and quality of raw and cooked chicken meat using new processing technologies will be the major issues in the future as they are now. Especially, the application of irradiation in raw and cooked chicken meat products will be increased dramatically within next 5 years. The market share of ready-to-eat cooked meat products will be increased. More portion controlled finished products, dark meat products, and organic and ethnic products with various packaging approaches will also be introduced.

• Sleep Medicine and Psychophysiology
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• v.4 no.1
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• pp.57-65
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• 1997

As jet lag of modern travel continues to spread, there has been an exponential growth in popular explanations of jet lag and recommendations for curing it. Some of this attention are misdirected, and many of those suggested solutions are misinformed. The author reviewed the basic science of jet lag and its practical outcome. The jet lag symptoms stemed from several factors, including high-altitude flying, lag effect, and sleep loss before departure and on the aircraft, especially during night flight. Jet lag has three major components; including external de synchronization, internal desynchronization, and sleep loss. Although external de synchronization is the major culprit, it is not at all uncommon for travelers to experience difficulty falling asleep or remaining asleep because of gastrointestinal distress, uncooperative bladders, or nagging headaches. Such unwanted intrusions most likely to reflect the general influence of internal desynchronization. From the free-running subjects, the data has revealed that sleep tendency, sleepiness, the spontaneous duration of sleep, and REM sleep propensity, each varied markedly with the endogenous circadian phase of the temperature cycle, despite the facts that the average period of the sleep-wake cycle is different from that of the temperature cycle under these conditions. However, whereas the first ocurrence of slow wave sleep is usually associated with a fall in temperature, the amount of SWS is determined primarily by the length of prior wakefulness and not by circadian phase. Another factor to be considered for flight in either direction is the amount of prior sleep loss or time awake. An increase in sleep loss or time awake would be expected to reduce initial sleep latency and enhance the amount of SWS. By combining what we now know about the circadian characteristics of sleep and homeostatic process, many of the diverse findings about sleep after transmeridian flight can be explained. The severity of jet lag is directly related to two major variables that determine the reaction of the circadian system to any transmeridian flight, eg., the direction of flight, and the number of time zones crossed. Remaining factor is individual differences in resynchmization. After a long flight, the circadian timing system and homeostatic process can combine with each other to produce a considerable reduction in well-being. The author suggested that by being exposed to local zeit-gebers and by being awake sufficient to get sleep until the night, sleep improves rapidly with resynchronization following time zone change.

• Journal of the Daesoon Academy of Sciences
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• v.33
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• pp.219-255
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• 2019

'Dao' is an important research subject as it is the main term for 'ultimate reality' in East Asian religious thought. Understanding the concept of 'Dao' is essential to reach the state of 'Perfected Unification with Dao,' the ultimate aspiration in Daesoon Thought. The meaning of 'Dao' can vary such as 'Dao' meaning 'way', which was first introduced in Jinwen. There is also the 'Dao' of yin and yang, and Dao used to mean human obligation, or Dao meaning the way of Heaven. These can also be classified into five categories: Constant Dao, Heavenly Dao, Divine Dao, Human Dao, and the Dao of Sangsaeng. Every natural phenomenon of birth, growth, and death in the universe operates under the patterns of Heaven and Earth. Therefore, Constant Dao in Daesoon Thought is the ultimate pattern underlying human action and the operations of Heaven and Earth. These apply not only to the natural and the divine world but also to the human world. It can be said that 'Rather than natural law or moral symbol of the world, 'Heavenly Dao' means the great Dao that saves the world through the Daesoon Truth of Sangje, Supreme God of the Ninth Heaven. Divine Dao can be said to be 'the Dao by which man must complete his work according to the law and the will of God,' that is, 'the Dao by which God and man are united together by Sangje's heavenly order and teaching, which aims for humanity, righteousness, propriety, and wisdom.' When the world is in a state of calamity and crisis, the request for the saint's Dao can symbolized by the kings, Yao and Shun, in The Canonical Scripture (Jeon-gyeong). The saint's Dao saves the dying world and people's lives and is called 'saving lives by curing the world (濟生醫世)'. It can be regarded as a characteristic of Human Dao in Daesoon Thought, which is the human obligation to follow Sangje's order, the great Dao to save the world. The Dao of Sangsaeng is the true dharma that rectifies the world full of mutual conflict through the ethics of the Later World, which is to promote the betterment of others and to practice the human Dao that saves the world and rebuilds the Constant Dao. Thus, The concept of Dao in Daesoon Thought is Daesoon Truth which applies to and operates throughout all realms of Heaven, Earth, Humanity, and the Divine world. Dao in Daesoon Thought was influenced by the historical background in which it emerged and this can be seen in its ideological features. It embraces the traditional concept of Dao, which refers to the Chinese classics and represents the main schools of thought in East Asia: Confucianism, Buddhism, and Daoism. And it is unique in that it implies the will of Sangje as a religious object, a supreme being. It can be seen that Daesoon Thought has developed through the process of defining the concept of Dao by harmonizing both the universality and specificity of modern Korean religious thought.