• Title/Summary/Keyword: National Science Fair

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Distributions of Endangered Fish Species and Their Relations to Chemical Water Quality-Ecological Stream Health in Geum-River Watershed (금강 대권역 대표 멸종위기 담수어류의 분포 특성 및 이화학적 수질-하천 생태건강도와의 관계분석)

  • Lee, Sang-Jae;An, Kwang Guk
    • Korean Journal of Environment and Ecology
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    • v.30 no.6
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    • pp.986-995
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    • 2016
  • The objective of this study was to analyze the distribution of endangered fish species and elucidate their relations on chemical water quality, physical habitat conditions and ecological stream health. The dominant species in the watershed was Pseudopungtungia nigra (Pn), Gobiobotia macrocephala (Gm), Gobiobotia brevibarba (Gb), Liobagrus obesus (Lo), and Iksookimia choii (Ic) in the order. The species of Pn designated as "critical endangered species (I) (CER)", was most widely distributed species among the endangered species, so the designation of the species should be re-evaluated. The endangered species was most popular (4 species, 384 individuals) in the Cho-River region of eighteen lotic regions. According to the analysis of chemical tolerance limits in the habitats with endangered fish species, biological oxygen demand (BOD) and total phosphorus (TP) was analyzed as "very good" (Ia) and "good condition" in the chemical criteria of the Ministry of Environment, Korea. Also, chemical conditions, based on ammonia-N ($NH_{4+}$), total nitrogen (TN), phosphate-P ($PO_{4^-}P$) were much better in the habitat with endangered species (Hw) than the habitat without endangered species (Ho). In the meantime, the species of Ic showed wide ranges on the chemical tolerance, so physical habitat conditions, such as the size of substrate particles (sand) and hydrological regime, were considered as more important factors than the chemical water quality, if the water quality is not largely degraded. The endangered species were also more distributed in the high-order (4-6) streams than the low-order (1-3) streams. The evaluation of ecological stream health, based on multi-metric model of the Index of Biological Integrity (IBI), showed the large difference between the Hw (21.6, fair condition)and Ho (30.5, good condition), indicating that the habitat maintained well chemically and physically had higher distributions of endangered species. Overall, the designation of CER on the Pn should be re-evaluated due to wide-distributions, and the protections from water pollution and the habitat conservations on the endangered species are necessary in the watershed.

Stream Health Assessment on Hoeya River Basin and Other Streams Based on Fish Community and Land Use in the Surrounding Watersheds (어류군집과 하천주변 토지이용에 따른 회야강 수계와 인근하천의 건강성 평가)

  • Kim, Jeong-Hui;Yoon, Ju-Duk;Jo, Hyunbin;Chang, Kwang-Hyeon;Jang, Min-Ho
    • Korean Journal of Ecology and Environment
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    • v.45 no.4
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    • pp.392-402
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    • 2012
  • In this study, to analyze the stream health using fish assemblage and make effective management, we conducted fish monitoring in the Hoeya River basin and neighboring streams. A total of 33 species classified into 12 families were collected from 29 sites in 2007. Dominant species was Zacco platypus (Relative abundance, RA: 24.8%), and subdominant species was Rhynchocypris oxycephalus (RA: 16.2%). Eight Korean endemic species and 4 exotic species were identified. Moreover, two species (Opsariichthys uncirostris amurensis and Hemiculter eigenmanni) were translocated from other basin. To evaluate stream health of the study sites, Index of Biological Integrity (IBI) was applied, based on fish assemblages. Overall, IBI values were "C (Fair)" or "D (Poor)" condition, according to the grade except two sites which recorded "B (Good)". The correlation between land use pattern of surrounding watershed and IBI was analyzed to verify impact of development on stream health using fish assemblage. As a result, when percentage of the developmental groups increased, IBI values were decreased (Pearson correlation, r=-0.425, p=0.022). In contrast, increment of percent forest and grass land was positively correlated with IBI (r=0.556, p=0.002). The agricultural group and IBI did not significantly correlate with each other (r=-0.231, p=0.333). In this study, we identified a relationship between land use of surrounding watershed and stream health using fish data (i.e. IBI). These results could be provided useful fundamental information to establish management and restoration plan in the Hoeya River basin and other rivers distributed in Korea.

Factors affecting pregnancy rates following transfer of bovine embryos derived from in vitro fertilization of oocytes matured in vitro (체외수정란 이식시 수태율에 미치는 요인에 관한 연구)

  • Kim, Sung-ki;Roh, Sang-ho;Lee, Eun-song;Lee, Byeong-chun;Hwang, Woo-suk
    • Korean Journal of Veterinary Research
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    • v.36 no.4
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    • pp.919-927
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    • 1996
  • In the last few years, methods for in vitro culture of early embryo stages from oocytes matured and fertilized in vitro using suitable cell culture systems have been established. But the factors affecting pregnancy rates following transfer of bovine embryos produced in vitro were not evaluated enough. So this study was performed to investigate the effects of quality and stage of embryos, parity and Corpus Luteum quality of recipients on pregnancy rates following non-surgical transfer of bovine embryos produced in vitro. Oocytes aspirated from small antral follicles of ovaries obtained at a local slaughter house were matured, fertilized with frozen-thawed semen and co-cultured for 6-7 days by utilizing co-culture system with bovine oviduct epithelial cell in vitro. After co-culture, embryos were transfered to recipients on day 7 (estrus=day 0). Recipients were monitored by ultrasonic scanning method or observation for estrus and rectal palpation after 50 days from transfer. The results of this study are follows. 1. Of the 70 recipients, 70%(49 of 70) had not showed estrus sign between day 0 and day 50, but 22.9%(16 of 70) was diagnosed not pregnant. Therefore the overall pregnancy rate of this study was 47.1%(33 of 70). 2. The pregnancy rate of recipients transfered with excellent(66.7%) and good(54.5%) embryos were higher than that of recipients transfered with fair embryos(15.8%) (p<0.05). 3. The pregnancy rate of recipients transfered with morula, compacted morula, blastocyst and expanded blastocysts were 46.2, 55.0, 62.5 and 50.0%, respectively. 4. The pregnancy rates of recipients transfered to heifer and cow were 54.5 and 55.2%, respectively. 5. The pregnancy rates of recipients with CL score I, II(66.7, 63.6%) were higher than those of recipients with CL score III (10%), (p<0.05). Success of transfer of embryos produced in vitro depends on many variables. The important factors identified in this study were the quality of embryos and the CL score of recipient animals after non-surgical transfer of embryos matured, fertilized and cultured in vitro.

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Cryptoporus volvatus (Peck) Shear: Mycelial characteristics under different culture conditions (한입버섯 균사체 특성과 배양 적정 조건)

  • Kyung-Hwa, Shin;Tae-Min, Park;Kyung-Gu, Min;Soon-Ja, Seok;Myung-Jun, Jang
    • Journal of Mushroom
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    • v.20 no.4
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    • pp.263-269
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    • 2022
  • This study investigated the culture characteristics of Cryptoporus volvatus, whichis grow naturally in Korea, to determine the suitable environmental conditions for its cultivation. The physiological characteristics of the mycelia were assessed according to the cultivation conditions, to determine the optimal conditions for artificial cultivation. The visual characteristics of the hyphae of Cryptoporus volvatus KACC52303 included an irregular and uneven surface and a fuzzy or cotton-like texture. Under the microscope, its microstructure showed pre-chlamydospore formation, but no clamps were seen. The appropriate culture temperature was found to be a medium/high temperature of approximately 25-30℃, and the optimal pH was found to have a wide range from weakly acidic (pH 4) to neutral (pH 7). In the optimal nutrient source experiment, hyphal growth was shown to be fair in a mixed medium with 2.5% dextrin as the carbon source and 0.1% yeast extract as the organic nitrogen source. Among the various amino acids, organic acids, and inorganic salts tested, the fastest hyphal growth was observed in the presence of leucine, acetic acid or gluconic acid, and KCl or KH2PO4, respectively. The column test showed that the best mycelial growth occurred in a mixed medium of 80% pine sawdust, 10% rice bran, and 10% corncob sawdust.

Usefulness of Acoustic Noise Reduction in Brain MRI Using Quiet-T2 (뇌 자기공명영상에서 Quiet-T2 기법을 이용한 소음감소의 유용성)

  • Lee, SeJy;Kim, Young-Keun
    • Journal of radiological science and technology
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    • v.39 no.1
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    • pp.51-57
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    • 2016
  • Acoustic noise during magnetic resonance imaging (MRI) is the main source for patient discomfort. we report our preliminary experience with this technique in neuroimaging with regard to subjective and objective noise levels and image quality. 60 patients(29 males, 31 females, average age of 60.1) underwent routine brain MRI with 3.0 Tesla (MAGNETOM Tim Trio; Siemens, Germany) system and 12-channel head coil. Q-$T_2$ and $T_2$ sequence were performed. Measurement of sound pressure levels (SPL) and heart rate on Q-$T_2$ and $T_2$ was performed respectively. Quantitative analysis was carried out by measuring the SNR, CNR, and SIR values of Q-$T_2$, $T_2$ and a statistical analysis was performed using independent sample T-test. Qualitative analysis was evaluated by the eyes for the overall quality image of Q-$T_2$ and $T_2$. A 5-point evaluation scale was used, including excellent(5), good(4), fair(3), poor(2), and unacceptable(1). The average noise and peak noise decreased by $15dB_A$ and $10dB_A$ on $T_2$ and Q-$T_2$ test. Also, the average value of heartbeat rate was lower in Q-$T_2$ for 120 seconds in each test, but there was no statistical significance. The quantitative analysis showed that there was no significant difference between CNR and SIR, and there was a significant difference (p<0.05) as SNR had a lower average value on Q-$T_2$. According to the qualitative analysis, the overall quality image of 59 case $T_2$ and Q-$T_2$ was evaluated as excellent at 5 points, and 1 case was evaluated as good at 4 points due to a motion artifact. Q-$T_2$ is a promising technique for acoustic noise reduction and improved patient comfort.

The Impact of K-IFRS Adoption on Accounting Conservatism: Focus on Distribution Companies (한국채택국제회계기준(K-IFRS)의 도입이 보수주의에 미치는 영향: 유통기업들을 중심으로 (초기 일시적 적응 현상))

  • Noh, Gil-Kwan;Kim, Dong-Il
    • Journal of Distribution Science
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    • v.13 no.9
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    • pp.95-101
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    • 2015
  • Purpose - This study provides evidence of the impact of the mandatory adoption of Korean equivalents to International Financial Reporting Standards (K-IFRS) on accounting quality. K-IFRS uses fair value as a basis of measurement and is characterized by principle-based standards. These characteristics can lead to a decrease in conservatism. Therefore, this study aims to examine whether or not there is a change in the level of conservatism before and after the enforcement of K-IFRS (2007~2014). By comparing 2007 through 2008 and 2013 through 2014 (excluding 2009 to 2012), we test "the temporary adjustment phenomenon" and document an overall decline in the degree of conservatism after the adoption of K-IFRS. Research design, data, and methodology - Our sample is comprised of data of all listed Korea Composite Stock Price Index (KOSPI) manufacturing distribution companies in Korea from 2007 to 2014, which yields the pooled sample of 4,412 (panel A) and 1,915 (panel B) firm-year observations for hypotheses 1 and 2. In line with recent literature, we adopt the Givoly and Hayn (2000) model, which recomputes the non-operating accruals, excluding two components that are most likely to capture the effect of restructuring activities: special items and gains or losses from discontinued operations. In addition, we also use these variables: SIZE, LEV, INV_CYCLE, ROA, OWN, and FOR. Results - Our sample period spans 2007 to 2014. This offers evidence on the effect of the mandatory adoption of IFRS on conservatism. Our findings can be summarized as follows. First, in panel A, for mandatory K-IFRS adoption (2011), we do not find any significant evidence of conservatism. We can guess that the "temporary adjustment phenomenon" is the reason that we do not find significant evidence of conservatism. Second, we investigate panel B from 2009 to 2012. We document an overall decline in the degree of conservatism after the adoption of K-IFRS. We can assume that these results are due to "the temporary adjustment phenomenon." Conclusions - This study finds that conservatism significantly decreased after IFRS adoption. In particular, this study makes the initial effort to elucidate "the temporary adjustment phenomenon" to analyze the effect of K-IFRS on conservative accounting. We argue that K-IFRS are conceptually conservative but that inappropriate application of the conservatism principles is likely to prevent financial reporting from reaching the level of conservatism targeted by the IASB. Overall, this paper contributes to the literature on IFRS and can be useful to capital market supervisors who are monitoring the trends of the firms implementing K-IFRS. Additionally, our results inform stakeholders of the potentially negative effect of the greater flexibility permitted by IFRS and/or lack of appropriate enforcement on key dimensions of accounting quality. This has important implications for Korean regulators and standard setters as they review the cost and benefits of IFRS. Our study also sheds light on the importance of the institutional environment in achieving the targeted objectives for improving financial reporting quality.

Fish Community and Estimation of Optimal Ecological Flowrate in Up and Downstream of Hoengseong Dam (횡성댐 상·하류의 어류군집 구조와 최적 생태유량 산정)

  • Hur, Jun-Wook;Kang, Hyoeng-Sik;Jang, Min-Ho;Lee, Jeong-Yeol
    • Journal of Environmental Science International
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    • v.22 no.8
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    • pp.925-935
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    • 2013
  • In this study, a comprehensive field monitoring was conducted to understand habitat conditions of fish species in up and downstream of Hoengseong Dam. Based on the monitoring data, riverine health conditions such as composition ratio of fish species, bio-diversity (dominance index, diversity, evenness and richness), index of biological integrity (IBI) and qualitative habitat evaluation index (QHEI) were assessed, and optimal ecological flowrates (OEF) were estimated using the habitat suitability indexes (HSI) established for three fish species Coreoleuciscus splendidus, Pungtungia herzi and Microphysogobio longidorsalis selected as icon species using the physical habitat simulation system (PHABSIM). The total number of species sampled was 20 species, and two species of Zacco platypus (30.4%) and C. splendidus (20.9%) dominated the fish community. As a result, it was revealed that IBI and QHEI values decreased from upstream to downstream along the river. The estimated IBI value ranged from 24 to 36 with average being 30.9 out of 50, rendering the site ecologically fair to good health conditions. HSI for C. splendidus were determined according to three different month in terms of season: Spring (April), Summer (August) and Autumn (October). HSI for flow velocity were estimated at 0.7 to 0.8 m/s for the Spring, 0.5 to 1.0 m/s for the Summer and 0.8 to 0.9 m/s for the Autumn. HSI for water depth were estimated at 0.3 to 0.5 m for the Spring; 0.3 to 0.5 m for the Summer; and 0.3 to 0.4 m for the Autumn. OEF was estimated at 4.2 and $6.5m^3/s$ for the Spring and Autumn, and $12.0m^3/s$ for the Summer. Overall, it was concluded that the Hoengseong Dam has been relatively well protected from the anthropogenic disturbance for the legally protected species including the endemic species studied in this study.

A Study on Exhibitional Suicide and Its Prevention (현시성 자살과 그 예방에 관한 고찰)

  • Park, Jin-Ho;Kwak, Jyung-Sik
    • Journal of forensic and investigative science
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    • v.1 no.2
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    • pp.20-30
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    • 2006
  • An exhibitional suicide is a case of death that the purpose is to demonstrate one's own real intention for others. This exhibitional suicide has a few characteristics that are different from a suicide: seriousness of suicide intention, a method of suicide attempt, and the place of a suicide. In other words, an exhibitional suicide lacks suicide intention, uses a slower method of death, and attempts a suicide at the place which others can easily find. In this light, this paper ascertains that a fair number in poisoning deaths are an exhibitional suicide on the basis of the result of an autopsy by department of forensic medicine school of medicine, Kyungpook National University. The research also confirms that juveniles and women attempt a suicide as often as adults and men, and a great number of suicides are indeed an exhibitional suicide. In terms of a commercial law, many specialists see an exhibitional suicide as an accidental death. However, if we consider an exhibitional suicide as an accidental death, we cannot verify the authenticity of death in an accident. In addition, if we observe the purpose of insurance and suicide exemption period of insurance company, we rather get to know to distinguish an exhibitional suicide from an accident. According to the research, most of the exhibitional suicide results from little or no-relation with others. Therefore, a little interest from family, friend, and neighbor plays a pivotal role in preventing this suicide. Finally, an effort to build database concerning an exhibitional suicide by a psychological autopsy will help people access a plenty of statistical materials and facilitate further study about an exhibitional suicide.

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Scientific Principles on the Revision and Addition of the Codex Nutrient Reference Values for Food Labelling Purposes (식품표시를 위한 코덱스 영양소기준치 개정에 필요한 과학적 근거)

  • Chang, Nam-Soo;Cho, Youn-Ok;Joung, Hyo-Jee;Chung, Hae-Rang;Kim, Hye-Young;Choi, Young-Sun;Lim, Hyeon-Sook;Yun, Jin-Sook;Kwon, O-Ran
    • Journal of Nutrition and Health
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    • v.42 no.2
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    • pp.183-188
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    • 2009
  • There has been a need to update the current Codex nutrient reference values (NRVs) which had been established following the Helsinki Consultation in 1988. The main purposes of NRVs are to help consumers compare the nutrient content of different food products and estimate the usefulness of a food product in terms of its percentage contribution to the overall healthful diets. The establishment of Codex NRVs for labelling purposes is intended to facilitate the goals of protecting consumers' health and ensuring fair practices in food trade. When revising the Codex NRVs several issues are needed to discussed, which are: 1) Consideration of population groups whether to have one set of NRVs for general population or to have several sets of NRVs for each population groups, 2) Determination of scope of nutrients such as what nutrients to include and what reference values to choose and 3) Development of principles for establishing NRVs such as the selection of suitable reference values among many including recommended intake/recommended dietary allowances, estimated average requirement and upper levels to extract NRVs. This paper will discuss the above issues and the inputs and efforts that the Korean Nutrition Society had put into to carry out the project, "International Collaboration on the Revision and Addition of the Codex Nutrient Reference Values for Food Labelling Purposes," and to ascertain relevant scientific principles and evidences that are utilized for establishment and revision of the Codex NRVs.

A Study on the Characteristics and Evaluation of the Policy in Japan's recent Reform of Education - Focus on the MEXT and CCE - (일본의 최근 교육개혁 정책의 특징과 평가 - 문부과학성과 중앙교육심의회를 중심으로 -)

  • Ko, Jeon
    • Korean Journal of Comparative Education
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    • v.26 no.4
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    • pp.173-198
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    • 2016
  • The purpose of this study is to analyze the characteristics of Educational Reforms Policy in lately Japan and to evaluate it. Especially focus on the activities of the [MEXT; Ministry of Education, Culture, Sports, Science and Technology] and [CCE;The Central Council for Education] This article composed of five chapters; Implication and problem situation, History of the Japanese educational reforms, the characteristics in the site of process of educational reforms policy, evaluation on the main policies, and Conclusion(contain the suggestion for Korea). The method of study composed of the literature search and interview. The System Analysis[input-process-output-feedback] is used as a model of the analyze the characteristics of educational reforms policy. By the new Basic Act on Education, the principles of educational administration is changed. Education administration shall be carried out in a fair and proper manner through appropriate role sharing and cooperation between the national and local governments(Article 16). As a conclusion, The initiative in the establishment of educational reform plans has gone over to the cabinet side from MEXT. And evaluate the five policies. That is Japan's Basic Plan for the Promotion of Education, The new Basic Act on Education(enacted on 2006), Provincial Governor's (Tokyo & Oska) Educational Reform Plan, Reform plan of the Boards of Education, and Improvement Policy of the Quality of Teachers.