• Composites Research
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• v.20 no.5
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• pp.13-19
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• 2007

Fiber-reinforced thermoplastic composites not only approach almost near to the strength of thermosetting composite but also has excellent productivity, recycling property, and impact resistance, which are pointed as weaknesses of thermosetting composites. The study for strength calculation of one direction fiber-reinforced thermoplastic composites and the study measuring precisely fiber orientation distribution were presented. Need the systematic study for the data base that can predict mechanical properties of composite material and fiber orientation distribution by the fiber content ratio was not constructed. Therefore, this study was investigated what affect the fiber content ratio and fiber orientation distribution have on the strength of composites. Fiber-reinforced thermoplastic composites by changing fiber orientation distribution and the fiber content ratio were made. Tensile strength ratio of $0^{\circ}$ direction of fiber-reinforced composites increased being proportional the fiber content and fiber orientation function as change from isotropy(J=0) to anisotropy(J=1). But, tensile strength ratio of $90^{\circ}$ direction by separation of fiber filament decreased when tensile load is imposed fur width direction of reinforcement fiber length direction.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.2
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• pp.57-65
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• 2008

Wastewater containing strong organic matter is very difficult to treat by utilizing general sewage treatment plant. but the wastewater is adequate to generate biomass energy (bio-gas; methane gas) by utilizing anaerobic digestion. EcoDays Plug Flow Reactor (E-PFR), which was already proved as an excellent aerobic wastewater treatment reactor, was adapted for anaerobic food wastewater digestion. This research was performed to improve the efficiency of bio-gas production and to optimize anaerobic wastewater treatment system. Food wastewater from N food waste treatment plant was applied for the pilot scale experiments. The results indicated that the efficiency of anaerobic wastewater treatment and the volume of bio-gas were increased by applying E-PFR to anaerobic digestion. The structural characteristics of E-PFR can cause the high efficiency of anaerobic treatment processes. The unique structure of E-PFR is a diaphragm dividing vertical hydraulic multi-stages and the inversely protruded fluid transfer tubes on each diaphragm. The unique structure of E-PFR can make gas hold-up space at the top part of each stage in the reactor. Also, E-PFR can contain relatively high MLSS concentration in lower stage by vertical up-flow of wastewater. This hydraulic flow can cause high buffering capacity against shock load from the wastewater in the reactor, resulting in stable pH (7.0~8.0), relatively higher wastewater treatment efficiency, and larger volume of bio-gas generation. In addition, relatively longer solid retention time (SRT) in the reactor can increase organic matter degradation and bio-gas production efficiency. These characteristics in the reactor can be regarded as "ideal" anaerobic wastewater treatment conditions. Anaerobic wastewater treatment plant design factor can be assessed for having 70 % of methane gas content, and better bio-gas yielding and stable treatment efficiency based on the results of this research. For example, inner circulation with generated bio-gas in the reactor and better mixing conditions by improving fluid transfer tube structure can be used for achieving better bio-gas yielding efficiency. This research results can be used for acquiring better improved regenerated energy system.

• The Journal of Korean Philosophical History
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• no.32
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• pp.215-249
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• 2011

This essay reflects on the modernity of Korea by examining the transformation of the traditional knowledge system from a historico-semantic perspective with its focus on the opposition and collision of the old and the new conception occurred in the early period(1890~1910) of the acceptance of the Western modern civilization. With scientific success, trick of reason, Christianity and evolutionary view of history, the Western modernity regarded itself as a peak of civilization and forced the non-Western societies into the world system in which they came to be considered as 'barbarism(野蠻)' or 'half-enlightened(半開).' The East Asian civilization, which had its own history for several centuries, became degraded as kind of delusion and old-fashioned customs from which it ought to free itself. The Western civilization presented itself as exemplary future which East Asian people should achieve, while East Asian past traditions came to be conceived as just unnecessary vestiges which it was better to wipe out. It can be said that East Asian modernization was established through the propagation and acceptance of the modern products of the Western civilization rather than through the preservation of its past experience and pursuit of the new at the same time. Accordingly, it is difficult to apply directly to East Asian societies Koselleck's hypothesis; while mapping out his Basic Concept of History, he assumed that, in the so-called 'age of saddle,' semantic struggle over concepts becomes active between the past experience and the horizon of expectation on the future, and concepts undergoes 'temporalization', 'democratization', 'ideologization', 'politicization.'The struggle over the old and new conceptions in Korea was most noticeable in the opposition of the Neo-Confucian scholars of Hwangseongsinmun and the theorists of civilization of Doknipsinmun. The opposition and struggle demanded the change of understanding in every field, but there was difference of opinion over the conception of the past traditional knowledge system. For the theorists of civilization, 'the old(舊)' was not just 'past' and 'old-fashioned' things, but rather an obstacle to the building of new civilization. On the other hand, it contained the possibility of regeneration(新) for the Neo-Confucian scholars; that is, they suggested finding a guide into tomorrow by taking lessons from the past. The traditional knowledge system lost their holy status of learning(聖學) in the process of its change into a 'new learning(新學),' and religion and religious tradition also weakened. The traditional knowledge system could change itself into modern learning by accepting scientific methodology which pursues objectivity and rationality. This transformation of the traditional knowledge system and 'the formation of the new learning from the old learning' was accompanied by the intersection between the old and new conceptions. It is necessary to pay attention to the role played by the concept of Sil(hak)(實學) or Practical Learning in the intersection of the old and new conceptions. Various modern media published before and after the 20th century show clearly the multi-layered development of the old and new conceptions, and it is noticeable that 'Sil(hak)' as conceptual frame of reference contributed to the transformation of the traditional knowledge system into the new learning. Although Silhak often designated, or was even considered equivalent to, the Western learning, Neo-Confucian scholars reinterpreted the concept of 'Silhak' which the theorists of civilization had monopolized until then, and opened the way to change the traditional knowledge system into the new learning. They re-appropriated the concept of Silhak, and enabled it to be invested with values, which were losing their own status due to the overwhelming scientific technology. With Japanese occupation of Korea by force, the attempt to transform the traditional knowledge system independently was obliged to reach its own limit, but its theory of 'making new learning from old one' can be considered to get over both the contradiction of Dondoseogi(東道西器: principle of preserving Eastern philosophy while accepting Western technology) and the de-subjectivity of the theory of civilization. While developing its own logic, the theory of Dongdoseogi was compelled to bring in the contradiction of considering the indivisible(道and 器) as divisible, though it tried to cope with the reality where the principle of morality and that of competition were opposed each other and the ideologies of 'evolution' and 'progress' prevailed. On the other hand, the theory of civilization was not free from the criticism that it brought about a crack in subjectivity due to its internalization of the West, cutting itself off from the traditional knowledge system.

• Korean Journal of Agricultural Science
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• v.33 no.1
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• pp.35-41
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• 2006

This study was conducted to investigate the developmental ability of interspecies cloned embryos after nuclear transfer of goat fetal fibroblast cells into porcien oocytes. Recipient porcine and goat oocytes were obtained from slaughterhouse and matured in vitro according to established protocols. Enucleation was accomplished by aspirating the first polar body and cytoplasm and a single donor cell was individually microinjected into vitelline space of the enucleated oocyte. The reconstructed oocytes were electrically fused with 0.3M mannitol fusion medium. After electro-fusion, interspecies reconstituted embryos were cultured in PZM-3 for 7 days. In porcine interspecies nuclear transfer with goat fetal fibroblast cells, the cleavage rate of reconstituted embryos were 58.9% which was no significant different from that in porcine nuclear transfer embryos (67.4%). However, the developmental rate into blastocyst stage was 5.4% in interspecies nuclear transfer which was significantly lower than that in porcine intraspecies nuclear transfer (13.6%). When the developmental ability of porcine interspecies nuclear transfer with goat cells was compared with goat intraspecies nuclear transfer, the cleavage rate of embryos were 59.2% and the developmental rate into morular and blastocyst stage was 13.6% in interspecies nuclear transfer which were significantly lower than those in intraspecies nuclear transfer embryos. This result indicated that porcine interspecies nuclear transfer with goat fetal fibroblast cells showed the developmental potential in vitro with lower cleavage and developmental rate compared with intraspecies nuclear transfer.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.6 no.1
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• pp.74-89
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• 1995

Selective mutism is a childhood condition defined by persisten failure to speak in specific social situation when speaking is expected, dispite preserved ability to comprehend spoken language and speak. Present study is to investigate clinical characteristics, treatment method and outcome of 23 children who were diagnosed as selective mutism by DSM-IV criteria at the child psychiatry ouptatient department of SNUH. The results were as follows : 1) The Sex ratio was 1: 4.8, female dominant Mear age of onset was 33 years old and mean age of first referral was 7.7 years old. 2) 22% of subjects had perinatal problem such as low birth weight, preterm birth, 26% of the subjects have history of delayed language development. There are subjects who had been separated with mam caretaker before 3 years old(26%) and who experienced physical or psychological trauma before 3 years old(26%). A few subjects had enurests(30%) and encoprests(4%). 3) Many subjects(65%) had symbiotic relationship with their mother. These families consist of dominant, verbally aggressive mother and passive father. Parents of 39% of all subjects were judged to have definite psychopathology(social phobic, depression, hysterical trait or alcohol problem) 26% of all subject, were reported physically abused. 4) The personality trait of the subjects were frequently described as follows(in order of frequency) ; Shy(100%), anxious(83%), stubborn(83%)m rigid and tense posture(78%), immature(65%) overdependent(65%), irritable(52%), manipulative(39%), depressive(39%). 5) The mean performance IQ of 16 subjects by KEDI-WISC was 88.3 Among them, the subjects with IQ below 69 were seven and those with IQ above 70 were nine. When comparing these two group(Mental retardation group vs Normal IQ group), we could find some difference in language development, personality trait, family dynamics and treatment outcome. 6) Among several treatment methods for selective mutism, play therapy was the most frequently used method(65%). Other commonly used treatment methods were pharmacotherapy(21%), behavioral therapy(8%), combined therapy(play therapy+pharmacotherapy+family therapy+behavioral therapy)(12%), 7) Regarding the outcome of treatment 8.6% was evaluated as Excellent, 30.4% as Good, 52% as Fair, 8.7% as Poor at the tinic of treatment. At follow up interview 21.7% was evaluated Excellent, 13% as Good, 21.7% as Fair, 34.8% as Poor. 8) We classified all subjects by Havden's 4 subtype. Symbiotic mutism was most common(65%) and other subtypes are Speech phobic mutism(8.6), Reactive mutism(13%) and Passive-aggressive mutism(30%).

• Journal of Oriental Neuropsychiatry
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• v.15 no.2
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• pp.149-158
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• 2004

만성적이거나 반복적인 스트레스는 우울중이나 심신병 등의 발병 기전과 밀접한 관련이 있다. 전기적 자극(electric foot shock), 한랭 자극, 속박(immobilization), 투쟁(fighting), 에테르 노출 등과 같은 심한 스트레스 자극이 뇌 조직의 시상 및 시상하부, 편도체 등에서의 노르아드레날린(noradrenalin) 방출을 유의 하게 감소시키는 동시에 혈청 corticosterone을 증가시키는 것으로 알려져 있다. 한의학에서는 스트레스 인자에 대한 신체반응을 기(氣)의 변화로 인식하고 있고, 이러한 자극요인들은 신체에 대하여 병적 요인을 제공하여 제반 질환을 야기한다. 또한 질병 발생에 대한 근거로 정기(正氣)와 사기(邪氣)의 상호 관계 위주로 인식하는데, 내부의 기(氣)의 변조(變調)는 질병의 발생을 야기하는 기초가 된다. 실험에 사용된 연근(蓮根)은 연꽃과에 속한 수생초본인 연꽃의 뿌리부분으로 우(藕) 또는 우절(藕節)이라는 명칭으로 불리기도 한다. 성미(性味)는 감(甘) 삽(澁) 평(平) 무독(無毒)하고 폐(肺) 위(胃) 간경(肝經)으로 들어가며 수렴지혈(收斂止血) 화어(化瘀)의 효능이 있어 토혈(吐血) 객혈(喀血) 뇨혈(尿血) 편혈(便血) 등의 각종 출혈 증상에 사용되어져 왔다. 최근 연꽃의 부위별 추출물이 흰쥐의 지질 과산화 생성을 효과적으로 억제하는 것으로 보고되고 있어 연근(蓮根)에 대한 다양한 약리 효능의 검색이 필요할 것으로 생각되며 연꽃의 씨앗인 연자육(蓮子肉)이 양심안신(養心安神)의 효능이 있어 스트레스성 질환에 많이 응용되고 있는 것에 착안하여 본 연구를 착수하였다. 실험 동물은 ICR계 마우스를 이용하였으며, 사회 심리적 스트레스는 옆쪽 cage에서 다른 마우스의 신체에 가해지는 전기 충격을 하루 1시간 동안 지켜보게 하는 것으로 유발하였으며 이 상태에서 약물을 투여한 그룹을 실험군, 그렇지 않은 그룹을 대조군으로 하였다. 정상군은 아무런 자극 없이 하루 1시간 동안 일정 공간에 가두어 두는 것으로 하였다. 실험 결과 사회 심리적 스트레스를 받은 경우에 아무런 처치를 하지 않은 대조군에 비해 연근 추출물을 100mg/kg/day 용량으로 5 일간 투여한 실험군에서 혈청 중 corticosterone 함량이 유의하게 감소하였으므로 매우 효과적으로 스트레스를 해소하였음을 알 수 있다. 뇌세포 중에서 신경전달물질로 분비되는 노르아드레날린의 분비량은 전반적으로 증가되는 경향을 나타내었으나 유의성은 없었다. 신체적 또는 사회 심리적 스트레스가 간 조직 내 지질의 과산화를 유발하는 것으로 나타났으며 연근 추출물이 이 결과에는 영향을 주지 못하였다. 사회 심리적 스트레스로 인하여 간 조직 내 지질과산화 정도가 증가하였으므로 혈청 내 ALT 함량도 따라 증가할 것으로 추정되었으며 이에 대한 연근 추출물 경구 투여가 간 조직을 보호할 수 있는지를 확인하기 위해 분리한 혈청으로부터 ALT 함량을 측정한 결과 대조군에 비하여 유의한 감소를 나타내었다. 또한 연근 추출물이 혈청 내 지질 과산화물의 생성을 억제할 수 있다면 질병의 예방과 치료에 효과적일 것으로 추정할 수 있으므로 그 생성량을 측정하여 보았으나 대조군과의 차이가 나타나지 않았다. 이상의 결과들을 종합하여 보면 스트레스가 부하된 5일 동안 연근(蓮根) 추출물을 함께 투여한 결과 혈청 corticosterone 함량을 유의하게 감소시켰고 뇌 조직내 noradrenaline 함량을 증가시키는 경향을 나타내어 스트레스 해소에 도움이 될 수 있음을 시사하였다. 또한 혈청 내 ALT 함량을 유의하게 감소시켜 스트레스로 인해 발생하는 간 기능의 손상도 어느 정도 억제시키는 것을 확인할 수 있었는데 앞으로 연근(蓮根)의 이러한 작용에 대한 보다 자세한 연구들이 필요한 것으로 생각된다.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1098-1103
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• 2003

Soybeans released proteins when immersed in water at $50{\sim}60^{\sim}C$. We investigated the changes in the characteristics of soybean when soaked in water at different temperatures and studied the electrophoretic properties of soy proteins in recommended Korean soybean varieties after heat treatment. Soybean seeds were heated in soaking water at temperatures of 30, 40, 50, 60, $70^{\circ}C$ for 90 min, and also from 10 to 150min at $60^{\circ}C$. The pH value of the water decreased with heating time at $60^{\circ}C$, and the amount of soluble solids increased with temperature and heating time. The protein concentration of the solution increased with temperature and time. From SDS-PAGE of the proteins in soaking water, we detected two new bands of 16 kDa- and 31 kDa-proteins from the Korean soybean varieties on heat treatment.

• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1236-1251
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• 1998

Background : TNF-$\alpha$ appears to be a central mediator of the host response to sepsis. While TNF-$\alpha$ is mainly considered a proinflammatory cytokine, it can also act as a direct cytotoxic cytokine. However, there are not so many studies about the relationship bet ween TNF-$\alpha$ level and lung injury severity in ALI, particularly regarding the case of ALI caused by direct lung injury such as diffuse pulmonary infection. Recently, a natural defense mechanism, known as the stress response or the heat shock response, has been reported in cellular or tissue injury reaction. There are a number of reports examining the protective role of pre-induced heat stress proteins on subsequent LPS-induced TNF-$\alpha$ release from monocyte or macrophage and also on subsequent LPS-induced ALI in animals. However it is not well established whether the stress protein synthesis such as HSP can be induced from rat alveolar macrophages by in vitro or in vivo LPS stimulation. Methods : We measured the level of TNF-$\alpha$, the percentage of inflammatory cells in bronchoalveolar lavage fluid, protein synthesis in alveolar macrophages isolated from rats at 1, 2, 3, 4, 6, 12, and 24 hours after intratracheal LPS instillation. We performed histologic examination and also obtained histologic lung injury index score in lungs from other rats at 1, 2, 3, 4, 6, 12, 24 h after intratracheal LPS instillation. Isolated non-stimulated macrophages were incubated for 2 h with different concentration of LPS (0, 1, 10, 100 ng/ml, 1, or 10 ${\mu}g/ml$). Other non-stimulated macrophages were exposed at $43^{\circ}C$ for 15 min, then returned to at $37^{\circ}C$ in 5% CO2-95% for 1 hour, and then incubated for 2 h with LPS (0, 1, 10, 100ng/ml, 1, or 10 ${\mu}g/ml$). Results : TNF-$\alpha$ levels began to increase significantly at 1 h, reached a peak at 3 h (P<0.0001), began to decrease at 6 h, and returned to control level at 12 h after LPS instillation. The percentage of inflammatory cells (neutrophils and alveolar macrophages) began to change significantly at 2 h, reached a peak at 6 h, began to recover but still showed significant change at 12 h, and showed insignificant change at 24 h after LPS instillation compared with the normal control. After LPS instillation, the score of histologic lung injury index reached a maximum value at 6 h and remained steady for 24 hours. 35 kDa protein band was newly synthesized in alveolar macrophage from 1 hour on for 24 hours after LPS instillation. Inducible heat stress protein 72 was not found in any alveolar macrophages obtained from rats after LPS instillation. TNF-$\alpha$ levels in supernatants of LPS-stimulated macro phages were significantly higher than those of non-stimulated macrophages(p<0.05). Following LPS stimulation, TNF-$\alpha$ levels in supernatants were significantly lower after heat treatment than in those without heat treatment (p<0.05). The inducible heat stress protein 72 was not found at any concentrations of LPS stimulation. Whereas the 35 kDa protein band was exclusively found at dose of LPS of 10 ${\mu}g/ml$. Conclusion : TNF-$\alpha$ has a direct or indirect close relationship with lung injury severity in acute lung injury or acute respiratory distress syndrome. In vivo and in vitro LPS stimulation dose not induce heat stress protein 72 in alveolar macrophages. It is likely that 35 kDa protein, synthesized by alveolar macrophage after LPS instillation, does not have a defense role in acute lung injury.