• Journal of The Korean Association For Science Education
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• v.22 no.4
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• pp.796-805
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• 2002

This study examined the knowledge structure constructed by children before formal instruction, and successive changes in the structural complexity of knowledge during and after the learning of 'Structure and Function of Plant' unit. It also investigated how those changes were affected by children's learning modes. The researchers made the 5th graders draw the first draft of their concept map to see the pre-existing knowledge structure concerned with the unit and four more concept maps after completing every fourth lesson. And to see how long their knowledge structures were preserved, the researchers made children draw additional concept maps in 3 days, 3 months, and 7 months after completing the unit. Children drew their current concept maps on the basis of the previous one while learning the unit and without the previous one after completing the unit. Each concept map drawn by children showed the degree of their current understanding on the structures and functions of plants. The results revealed that only two levels of hierarchy and five relationships among the components of the first concept map(relationship, hierarchy, cross link and example) were proven to be valid in terms of conceptual relevance. Growth in the structural complexity of knowledge took place progressively throughout the unit and the effects of learning mode on the growth were favorably reflected in concept map scores of meaningful learners over time(relationship, cross link, example: p<.01, hierarchy: p<.05). Although there were some differences on the concept map scores between two types of learners, they commonly showed that knowledge restructuring had occurred apparently in the early periods from the 1st to the 6th lesson and had not occurred at all in the last period of the unit. The frequency of tuning was higher in rote learners than in meaningful learners throughout the unit, but the frequency of accretion was reverse. Concept map scores of rote learners constructed in the course of learning of the unit decreased little by little gradually in all the categories after completing the unit. However, the average total map score of meaningful learners increased a little more in 7 months than in 3 months after completing the unit. Therefore it can be inferred that meaningful learners construct more stable and well-differentiated knowledge structures than the rote learners.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.4
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• pp.56-63
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• 1986

This study was designed to be link in the chain of the investigation on daily life and consciousness of longevous people in Korea, and to investigated the dietary life and its habit of longevous people in the past. The dietary life ana its habit were surveyed on 379 subjects (male 121, female 258) of the aged who were above 80 years of age, from June to November in 1985. 1. Of the taste on staple food of longevous peoples in the past(between 40 and 60 years), 'meal mixed with barley' had the highest figure of 49.9%, followed by 'boiled rice'(47.0%). But it is showed that male preferred 'meal mixed with barley'(56.2%) to 'boiled rice'(41.3%). whereas female slightly preferred 'boiled rice'(49.6%) to 'meal mixed with barley'(46.9%). 2. Of the experience of the food taste of these aged in the past, 'not salted' and 'light' had the highest figures of all 40.6%. It is showed that longevous peoples preferred 'not salted'(40.6%) and 'light'(40.6%) to 'salty'(24.5%) and 'oily'(9.8% ), respectively. 3. By comparison of the intake state of animal protein(meat and fish) of these aged in the past, 'occasionally' was the highest of 55.4%, and decreased in the order of 'almost daily'(31.9%) and 'scarcely'(12.7%). Therefore, it is believed that 87.5% of longevous peoples has taken animal protein 'occasionally' and 'almost daily'. 4. The intakes of major foods above $4{\sim}6$ times a week of these aged in the past and present showed 50.4% and 67.5% for meat, fish, egg and soybean products, 26.6% and 51.5% for milk and its products, 89.9% and 81.0% for vegetables, 58.9% and 64.0% for oiled food, and 57.0% ana 62.934 for seaweeds, respectively.

• The Korean Journal of Air & Space Law and Policy
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• v.31 no.1
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• pp.37-62
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• 2016

Two controversial issues exist in interpretation of "Force Majeure" set forth in the Article 931 (4) of the Korean Commercial Code. Firstly, its scope of application is ambiguous. Secondly, there is a concern that the "immunity" under paragraph 1 and "Force Majeure" may overlap each other. "Force Majeure" refers an event resulted from either natural disaster or 3rd-party. Meanwhile, the latter implies relatively extensive and comprehensive meaning and its interpretation may vary depends on law enforcement. In general, the aircraft accident hardly results in damage or loss to the 3rd-party. Additionally, it is worth to review newly enacted clause and to define its applicability. When the 3rd party is suffered from damage or loss incurred by any external act, it is necessary to explicit the concept of the non-contractual liabilities with respect to 3rd party. From the perspective of protecting aviation industries, the commercial aviation operator may be entitled to immunity in respect of claim for damage incurred by the event of Force Majeure. However, this approach is directly opposite to the victim's benefit and protection by the law. Therefore, the priority of the legal protection should be considered. Although the interest of the commercial aviation operator is not negligible, the protection of the law should be favorable to the 3rd party. Otherwise, the innocent party has no right to claim for damage incurred by aviation accident. Another issue is about the possibility of overlapping of the provision set forth in the paragraph 1 and 4. The former states that the liabilities shall be exempted on account of either the unsettled political or economic situation but this clause is inconsistent with the interpretation on Force Majeure under the latter. As argued above, this may include any event resulted from either political or economic account by the external influence of the 3rd party, thus these two provisions are overlapped. Consequently, in order to develop ordinances and guidelines and to ensure an equal protection to both parties, above two issues must remain open for further discussions.

• The Korean Journal of Applied Statistics
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• v.27 no.7
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• pp.1243-1255
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• 2014

This study is aimed at developing an index and indicator in the light of social factors by analyzing the basic materials on Korean working conditions survey to make it possible to grasp various working environment factors consequent on business type and to judge the industrial safety & health policy of the related area. For the purpose of developing an index, this study was conducted by benchmarking the OECD-suggested index development guidelines and overseas cases of index development. This study suggested indexes related to health by benchmarking OECD's press-state-response model. The press-state health-related indexes specified in Korean working condtions survey were found to consist of physical risk environment, working hours, business environment, and social environment, and its consequent 'state' items were comprised of mental health, physical health, absence from work due to health problems and work satisfaction as health-related items. As a result, it was found that the 'press-state index' for wage worker, regular employee, manager, clerks, expert & related personnel involved, and workers aged under 50 was relatively good; in contrast, the 'press-state index' for people aged over 50, owner-operator, daily job, skilled position in agriculture & fisheries, simple labor service, and apparatus & machines assembly worker was found to be relatively vulnerable.

• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.330-335
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• 2011

This study was performed to determine the transfer rates of each foodborne pathogen from pork meat packaging during the processing. We analyzed the transfer rate of Listeria monocytogenes from contaminated pork meat to worker's hands (wearing polyethylene gloves, PEG; cotton gloves, CG; and bare hands), cutting boards and knives, and vice versa. Transfer rate of CG 100.00% was higher than that of bare hands 2.513% and PEG 1.511%. In particular, when wearing Co, the transfer rate from the CG to bare hands with CG was 0.08%. Also, the range of transfer rates from contaminated pork meat to cutting board and knife was 0.352-3.791%. In contrast, transfer rates from the workers' hands (with PEG/CG and bare hands) to cutting board, knife, and pork meat ranged from 0.001 to 0.141%. There was a lower transfer rate from workers' hands than from pork meat. These findings indicate that use of PEG could effectively reduce or prevent the cross-contamination compared to CG and provide important information concerning the consecutive transfer of L. monocytogenes during food processing.

• Journal of Chest Surgery
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• v.35 no.2
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• pp.118-126
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• 2002

배경: 체외순환에 의해 생성되는 염증매개체는 소아 환자에서 술 후 다기관 기능부전과 연관이 있다. 본 연구에서는 선천성 신장질환 소아환자에서 체외순환에 의한 전염증성 사이토카인과 케모카인의 유전자 발현 특성에 대해 알아보고자 하였다. 대상 및 방법: 개심술을 시행한 18명의 소아 환자의 요골 동맥에서 마취유도 후(기준치), 체외순환(0시간), 체외순환 2시간 후 24시간 후, 48시간 후에 혈액을 채취하였다. 모든 환자에서 인터루킨-1알파, 인터루킨-1베타 인터루킨-6, 인터루킨-8, 종양괴사자인자-알파, 인터루킨-15,인터페론 감마의 mRNA의 유전자 발현 정도를 반정량적으로 역전사 중합효소 연쇄반응으로 측정하였다. 6명의 환자에서 인터루킨-6단백치는효소결합면역흡착검사로 측정하였다. 결과: 전신적인 인터루킨-6 mRNA와 비슷한 양상을 보였으나 최고치는 인터루킨-6보다 낮은 값을 보였다. 인터루킨-1알파와 인터루킨-1베타의 mRNA의 발현은 체외순환 2시간 후에 최고치를 나타내었고 체외순환 2시간 후에 최고치를 나타내었고 체외순환 48시간 후에 감소하였다. 종양괴사자인자-알파는 체외 순환 24시간 후에 최고치를 나타내었고 체외순환 48시간 후에 감소하였다. 인터루킨-15 mRNA 발현은 체외순환 전후와 비교하여 유의한 변화가 없었다. 인터페론-감마는 시간이 지남에 따라 감소하였다. 결론: 선천성 심장질환으로 개심술을 시행한 소아환자의 혈청 내 인터루킨-6, 인터루킨-8, 인터루킨-1알파, 인터루킨-베타, 종양괴사자인자-알파의 유전자 발현은 체외 순환 전후로 유의한 변화를 보였다. 인터루킨-15는 유의한 변화가 없었고 인터페론-감마는 반대 양상의 변화를 보였다. 체외순환 후 전염증성 사이토카인과 케모카인의 높은 혈중 농도는 술 후 조직 손상과 연관되리라 생각한다.

• Food Science of Animal Resources
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• v.25 no.3
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• pp.285-294
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• 2005

The objective of this study was to evaluate the physico-chemical properties and flavor compounds of sausages with various levels and molecular weight (MWs) of chitosans, during storage at $4^{\circ}C$. Various MWs (Low: 1.5 kDa; Medium: $30{\sim}50$ kDa; High: 200 kDa) and two levels (0.3 and $0.6\%$) of chiosans were dissolved and measured the viscosity at $4^{\circ}C$, pH values were not affected (p>0.05) by either MWs or levels of chitosans. The addition or high MWs or chitosan into the pork salt soluble protein (SSP) increased the viscosity, whereas no differences were observed in low and medium MWs of chitosan. Textural profile analysis (TPA) was affected by the addition of medium or high MWs of chitosan. As a result, the addition of medium of chitosan increased the hardness, gumminess, chewiness, cohesiveness and springiness values, whereas increased level of chitosan didn't affect TPA values, except few cases. Approximately twenty-nine flavor compounds were identified in the low-fat and regular-fat sausages, however the addition of chitosans didn't impair the flavor composition of the sausages, These results indicated that the addition of chitosans didn't affect the flavor profiles, but affected the textural properties in the sausages, especially MWs higher than 30 kDa.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.157-162
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• 1987

The study was carried out to investigate the effects of light intensity, temperature and seasonal trends on the photosynthesis as well as the physiological characteristics of Panax species and cultivars. Four-year-old plant of Violet-stem variant, Yellow-berry variant, Mimaki and Russian ginseng of Panax ginseng C. A. Meyer and American ginseng of Panax quiquefolium L. were used for study. These Panax species and cultivars were cultivated under the straw shading. The light saturation point of leaves in Violet-stem variant, Yellow-berry variant, Mimaki and American ginseng were 15,000 lux, but that of Russian ginseng was 10,000 lux. The optimum air temperature on the phtosynthesis of Violet-stem variant, Yellow-berry variant, Mimaki and American ginseng were 20$^{\circ}C$ but that of Russian ginseng was 15$^{\circ}C$ under 15,000 lux. The photosynthetic rates were increased in order of Russian ginseng, Mimaki, Yellow-berry variant, Violet-stem variant and American ginseng. The respiration rates of ginseng leaves were increased according to the increasing of temperature, but it was not different among Panax species and cultivars. Stomata frequency of American ginseng was highest, that of Russian ginseng lowest, while the length of stomata was reverse. The total chlorophyll content of American ginseng and specific leaf weight of Mimaki were higher than other ginseng cultivars. The root weight of American ginseng was heavier than others, but that of Russian ginseng was lighter. The num ber of leaflets per plant of 2-year-old plant and the root weight of 6-year-old plant were increased in order of Russian ginseng, American ginseng, Mimaki, Yellow-berry variant and Violet-stem variant.

• Journal of Sensor Science and Technology
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• v.10 no.2
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• pp.125-133
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• 2001

Conducting polymer sensors show high sensitivity when exposed to volatile organic compounds gases at room temperature. The 8 sensor array using by polypyrrole and polyaniline has been fabricated by chemical polymerization for measuring sensing characteristics of VOCs gases. Conducting polymer was polymerized by using distilled pyrrole, aniline as a monomer and ammonium persulfate (APS) as an oxidant and dodecylbenzene sulfonic acid (DBSA) as a dopant. Dedoped film was synthesized by reverse voltage and redoped film was synthesized by using 1-octanesulfonic acid sodium salt as another dopant in electrochemical cell. The sensitivity and reversibility were influenced by doping, dedoping, redoping and thickness for the polypyrrole and polyaniline. We investigated the relation between the structure of conducting polymer and sensitivity of these sensors through the analysis of scanning electron microscope (SEM), scanning probe microscope (SPM) and $\alpha$-step.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.116-125
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• 2017

Alpine plants with a scarcity of pollinators in harsh environments have been believed to undergo selfing for reproductive assurance; however, contradictory evidence is also available. Snowmelt regimes in alpine areas function to change life history characteristics of alpine plants such as flowering time and duration; yet the effects of snowmelt regimes have never been tested in alpine plants in Korea. This study was conducted to investigate the dichogamy, mating systems, and flowering characteristics of Megaleranthis saniculifolia populations [early and late snowmelt plots (ESP and LSP, respectively)] in a subalpine area of Sobaeksan Mountain in Korea. M. saniculifolia exhibited incomplete protogyny in that despite early maturation of pistils, maturation times of pistils and stamens within flowers were partly overlapped. Control and hand-outcrossing treatments produced significantly higher number of follicles and seeds per flower than autonomous and hand-selfing treatments. Based on the aggregate fruit set, the auto-fertility index (AI) and self-compatibility index (SI) were 0.33 and 0.50, respectively. Snowmelt occurred 10 days earlier in ESP than in LSP, thereby ESP and LSP showed distinct differences with regard to flower longevity and season, but showing no difference in peak flowering dates. We concluded that M. saniculifolia is an incomplete protogynous and largely outcrossing plant requiring pollinator service. Temporal variation in snowmelt time and subsequent changes in flowering characteristics under climate change may further threaten the population persistence of M. saniculifolia which has already been designated as endangered species in Korea.