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        검색결과 23

        2.
        2021.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        It has been established that the acoustic mode parameters of the Sun and Sun-like stars vary over activity cycles. Since the observed variations are not consistent with an activity-related origin, even Sun-like stars showing out-of-phase changes of mode frequencies and amplitudes need to be carefully studied using other observational quantities. In order to test whether the presumed relations between the global seismic parameters are a signature of the stellar activity cycle, we analyze the photometric light curve of HD 49933 for which the rst direct detection of an asteroseismic signature for activityinduced variations in a Sun-like star was made, using observations by the CoRoT space telescope. We nd that the amplitude of the envelope signi cantly anti-correlates with both the maximum frequency of the envelope and the width of the envelope unless super are-like events completely contaminate the light curve. However, even though the photometric proxy for stellar magnetic activity appears to show relations with the global asteroseismic parameters, they are statistically insigni cant. Therefore, we conclude that the global asteroseismic parameters can be utilized in cross-checking asteroseismic detections of activity-related variations in Sun-like stars, and that it is probably less secure and efective to construct a photometric magnetic activity proxy to indirectly correlate the global asteroseismic parameters. Finally, we seismically estimate the mass of HD 49933 based on our determination of the large separation of HD 49933 with evolutionary tracks computed by the MESA code and nd a value of about 1:2M and a sub-solar metallicity of Z = 0:008, which agrees with the current consensus and with asteroseismic and non-asteroseismic data.
        4,000원
        3.
        2021.08 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        It has been known that the global asteroseismic parameters as well as the stellar acoustic mode parameters vary with stellar magnetic activity. Some solar-like stars whose variations are thought to be induced by magnetic activity, however, show mode frequencies changing with di erent magnitude and phase unlike what is expected for the Sun. Therefore, it is of great importance to nd out whether expected relations are consistently manifested regardless of the phase of the stellar magnetic cycle, in the sense that observations are apt to cover a part of a complete cycle of stellar magnetic activity unless observations span several decades. Here, we explore whether the observed relations of the global seismic parameters hold good regardless of the phase of the stellar magnetic cycle, even if observations only cover a part of the stellar magnetic cycle. For this purpose, by analyzing photometric Sun-as-a-star data from 1996 to 2019 covering solar cycles 23 and 24, we compare correlations of the global asteroseismic parameters and magnetic proxies for four separate intervals of the solar cycle: solar minima 2 years, solar minima +4 years, solar maxima 2 years, and solar maxima +4 years. We have found that the photometric magnetic activity proxy, Sph, is an e ective proxy for the solar magnetic activity regardless of the phase of the solar cycle. The amplitude of the mode envelope correlates negatively with the solar magnetic activity regardless of the phase of the solar cycle. However, relations between the central frequency of the envelope and the envelope width are vulnerable to the phase of the stellar magnetic cycle.
        4,000원
        5.
        2016.05 구독 인증기관 무료, 개인회원 유료
        Do automobile test drive reviews really deliver objective information to consumers with scientific expressions? For the analysis, samples were collected from eighteen media outlets -- ten Korean and eight foreign. Collected samples of car reviews were analyzed in terms of sentence unit and classified into two categories: either a sentence with scientific expressions or a sentence with non-scientific expressions. Result showed that car review from 9 medias only had portion of sentence with scientific expressions exceeding 50 percent. Result supports this research's hypothesis that "test drive review of automobile isn't scientific."
        4,000원
        6.
        2015.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        목 적: 근시성 난시안에 대하여 핀홀에 의한 시력변화를 연구하였다. 방 법: 안질환이 없고 질환에 의해 시력손상이 없는 20대에서 30대 성인을 대상으로 하였다. 핀홀의 직 경을 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm로 설정하여, 핀홀렌즈 직경에 따른 시력을 비교하였다. 표준 조도 200 lux와 밝은 조도(380~500 lux)에 대하여 조도에 따른 핀홀시력을 검사하였다. 또한 눈의 상태를 나안 상태, 구면 굴절력 가입상태, 등가구면 굴절력 가입 상태, 세 가지로 구분 하여 핀홀시력을 검사하였다. 결 과: 여섯 가지 조건을 비교하였는데, 나안 상태일 때 조도에 상관없이 가장 직경이 작은 0.5 mm에 서 핀홀시력이 상승하였고, 직경이 커짐에 따라 단계적으로 핀홀시력이 감소하였다. 구면 굴절력과 등가 구 면굴절력을 가입하고, 핀홀시력을 비교하였을 때 1.5 mm, 2.0 mm 직경에서 시력상승이 두드러지게 나타났다. 하지만 0.5 mm 직경에서 오히려 시력이 떨어졌다. 단안 보다 양안에서 핀홀시력이 상승하였다. 결 론: 나안 상태에서 초점심도와 피사체심도, 수차 보정에 영향을 받아 직경이 가장 작은 렌즈에서 시 력이 가장 많이 상승하였다. 구면 굴절력과 등가구면 굴절력 가입상태일 때, 망막 위에 후초선과 최소착란원이 놓이게 되면서 나안 상태에 비해 초점심도와 피사체심도의 영향보다는 망막 조도의 영향이 큰 것으로 보인다. 단일 핀홀렌즈에서도 양안가중효과(binocular summation)의 영향이 있는 것으로 판단된다.
        4,000원
        8.
        2015.01 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Hot rolling of Mg-6Zn-0.6Zr-0.4Ag-0.2Ca-(0, 8 wt%)Li powder was conducted at the temperature of 300 oC by putting the powder into the Cu pipe. The microstructure and mechanical properties of the samples were observed. Mg-6Zn- 0.6Zr-0.4Ag-0.2Ca without Li element was consisted of α phase and precipitates. The microstructure of the 8 wt%Li containing alloy consisted of two phases (α-Mg phase and β-Li phase). In addition, Mg2Zn3Li was formed in 8%Li added Mg-6Zn-0.6Zr- 0.4Ag-0.2Ca alloy. By addition of the Li element, the non-basal planes were expanded to the rolling direction, which was different from the based Mg alloy without Li. The tensile strength was gradually decreased from 357.1 MPa to 264 MPa with increasing Li addition from 0% to 8%Li. However, the elongation of the alloys was remarkably increased from 10 % to 21% by addition of the Li element to 8%. It is clearly considered that the non-basal texture and β phase contribute to the increase of elongation and formability.
        4,000원
        9.
        2013.10 구독 인증기관·개인회원 무료
        Probles is apredominantly Holarctic genus with about 44 species in the Palearctic region (Yu et al. 2012). Palearctic fauna of Probles is rather irregularly studied: West European species were revised by Horstmann (1971, 1981; Horstmann and Kolarov 1988), and Palearctic species of five small subgenera, Microdiaparsis Horstmann, Probles s. str., Rhynchoprobles Horstmann, and Rugodiaparsis Horstmann, were reviewed by Khalaim (2003), whereas the most species rich subgenus, Euporizon Horstmann, is virtually unknown outside Europe. Only two species of Euporizon, P. (E.) sibirica Khalaim, 2007 from Mongolia and Russian Siberia and P. (E.) vulnifica Khalaim & Sheng, 2009 from the Palearctic part of China, are known to occur in the East Palearctic region, and one Oriental species, P. (E.) vietnamica Khalaim, 2011, was recently described from Vietnam (Khalaim, 2011; Khalaim and Sheng 2009). Some species of Probles were recorded as parasitoids of the beetle families Ciidae, Curculionidae, Endomycidae, and Melandryidae in Europe (Horstmann 1971, 1981). In this paper, we describe three closely related new species of Euporzon belonging to one species-group. Three closely related species of the genus Probles Förster, P. fulgida sp. n., P. korusa sp. n., and P. rukora sp. n. differ from other Palearctic species of the genus based on a combination of long and weakly sinuate apically ovipositor and short temple. A portion of the key for identification of this species-group is provided here.
        10.
        2013.10 구독 인증기관·개인회원 무료
        Rhyssinae Morley, 1913 is a relatively small group belonging to the family Ichneumonidae and recorded 286 species in eight genera from the world. Most rhyssines are Idiobiont ectoparasitoid of wood boring Symphyta and Coleoptera. South Korean Rhyssinae were poorly known. In the recent study of the Rhyssinae of South Korea, only four species belonging to the genera Megarhyssa and Rhyssa, have been reported: M. gloriosa (Matsumura), M. jezoensis (Matsumura), M. praecellens (Tosquinet) and R. persuasoria (Linnaeus). Five genera of the subfamily Rhyssinae (Epirhyssa, Megarhyssa, Rhyssa, Rhyssella and Triancyra) are recognized in South Korea. Two genera, Megarhyssa and Rhyssa, were previously recorded from South Korea, whereas the other three genera are recorded for the first time in Korea. A key to the five genera of Rhyssinae occurring in South Korea is provided. Genus Epirhyssa is reviewed here, and a key to the four species (E. latimandibularis (Hu & Wang), E. moiwana Matsumura, E. sapporensis Uchida and E. nigrithorax sp. nov.) is provided.
        11.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The role of Fatty acid binding protein 4 (FABP4) gene is critical for lipid metabolism and for maintaining homeostasis in adipocytes. Association between Hanwoo carcass traits and FABP4 gene g.7516G>C SNP has been reported previously, however, its association and how does it influence Korean brindle and black cattle has not been demonstrated and established till date. For this purpose, the study was planned to analyze the SNP association (Single Nucleotide Polymorphism) (g.7516G>C) in FABP4 gene and gather genetic information on economic traits of Korean brindle cattle and black cattle. As per sequence of bovine FABP4 gene available (Genbank accession No. NC_007312.4), one pair of primers (5’-ATA TAG TCC ATA GGG TGG CAA AGA-3’ and 5’-AAC CTC TCT TTG AAT TCT CCA TTC T-3’) was designed to amplify a 452bp product of the FABP4 gene including the region of 7417–7868. The SNP, detected by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) methods using restriction enzyme MspA1I, was genotyped in 117 animals of brindle cattle and 24 animals of black cattle population. Statistical analysis revealed that the FABP4 genotype significantly (p<0.05) affect with carcass weight, but there was no significant association with any other economic traits was observed in brindle as well as in black cattle. In conclusion, these results suggested that SNP (g.7516G>C), located in FABP4 gene, could be used as important DNA marker of economic traits in Korean brindle cattle. Furthermore, we suggest that additional samples needs to further analysed to make related data exclusively authentic.
        4,000원
        12.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The melanocortin receptor type 4 (MC4R) gene is expressed in the hypothalamus and regulates energy intake and body weight. Recently, it has been reported that obesity and energy balance in human were also regulated by the MC4R gene. Therefore the objective of this study was to identify the polymorphism on the MC4R gene SNP C1786T and its association with economic traits in Korean native cattle (brindle and black cattle) by PCR-RFLP. A total of 125 cattle from the two breeds were tested for economic traits (meat quality index, backfat, thickness, carcass weight, longissimus muscle area and marbling score) and data was analyzed using SAS program. In the results, C allele had highest frequency than G allele frequency in the both breeds and the gene was significantly associated with meat quantity index and backfat thickness in brindle cattle breed. However, in black cattle, the gene was significantly associated with longissimus muscle area (p<0.05). These results suggest that C1786T SNP of the MC4R gene may be useful as a genetic marker for economic traits in the brindle and black cattle.
        4,000원
        13.
        2012.10 구독 인증기관·개인회원 무료
        For the taxonomic studies of the subfamily Rhyssinae (Hymenoptera: Ichneumonidae), specimens were collected from March of 2001 to June of 2012 in the south Korean. For the present work, 400 specimens which collected form various laboratories in Korea and in other countries. As a result of taxonomic study, a total of 5 genera, 13 species was confirmed in Korea Rhyssinae. Additionnal discriptions, collection sites, korean records, distribution, host, keys are provided for all 13 species. The Korean of species Rhyssinae and host are listed as followes. Subfamily Rhyssinae Morley, 1913 Genus Epirhyssa Cresson, 1865 Epirhyssa nitobei Uchida, 1928 Genus Megarhyssa Ashmead, 1900 Megarhyssa gloriosa (Matsumura, 1912) Megarhyssa jezoensis (Matsumura, 1912) Megarhyssa praecellens (Tosquinet, 1889) Megarhyssa n.sp 1 Megarhyssa n.sp 2 Megarhyssa n.sp 3 Megarhyssa n.sp 4 Megarhyssa n.sp 5 Genus Rhyssa Gravenhorst, 1829 Rhyssa persuasoria (Linnaeus, 1758) Genus Rhyssella Rohwer, 1920 Rhyssella furanna (Matsumura,1912) Genus Triacyra Baltazar, 1961 Triancyra galloisi (Uchida, 1928) Triancyra hirashimai Momoi, 1970
        14.
        2012.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Stearoyl-CoA desaturase (SCD1) gene plays important role in fatty acid composition. In order to find marker-assisted selection (MAS) for improving the economic trait, this study was performed to identify the 878T>C single nucleotide polymorphism (SNP) on SCD1 gene. Three genotypes (CC, CT, and TT) were detected in 878T>C SNP of SCD1 gene from 103 Hanwoo population by polymorphism chain reaction-restriction fragment length polymorphism (PCR-RFLP) and economic traits were analyzed by general linear model. The frequency of allele C and T was 0.534 and 0.466, also the genotype frequency of CC, CT and TT was 0.252, 0.563, and 0.184, respectively in the Hanwoo population. The TT genotype of SCD1 gene showed a significantly higher measures (p<0.05) of carcass weight (CW) than CT, CC genotype. No significant association was detected between genotype and other economic trait (marbling, backfat thickness, and longissimus muscle area) in this study. The results revealed that SCD1 gene 878T>C SNP could be useful for effective MAS to increase the economic quality in Hanwoo population.
        4,000원
        15.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Myopalladin (MYPN) is an important expression gene associated with regulation of Z-line structure in muscle and maintains sarcomeric integrity. In this study, we investigated the association between MYPN A1795G SNP (single nucleotide polymorphism) and carcass traits (LMA, longissimus muscle area; CW, carcass weight; BF, backfat thickness; MS, marbling score) in Korean cattle. The MYPN A1795G SNP was genotyped in 212 steers and analyzed the associations with carcass traits by PCR-RFLP (Restriction fragment length polymorphism) method. The allele frequencies were 0.566 for G allele and 0.434 for A allele. And the genotype frequencies of GG, GA, and AA genotype were 32.1%, 49%, and 18.9%, respectively. Association analysis indicated that the A1795G SNP of MYPN gene showed a significant association with LMA (p<0.05). The steers with GG genotype had higher LMA than those with the genotypes AA. But no significant associations were observed in other carcass traits (CW, BF, MS). The steers with the GG genotype showed higher CW and BF than those with the genotypes AA and GA. These results suggest that the A1795G SNP of the MYPN gene is associated with LMA and may be useful for candidate marker-assisted selection to increase the levels of LMA in Korean cattle.
        4,000원
        16.
        2011.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Enforcement of the beef traceability system can block the sale of imported beef disguised Hanwoo and help customers to know detailed information of the Hanwoo beef while purchase. This study was carried out to investigate the possibilities of identifying DNA upon various ripening and roasting methods (soy sauce, gochujang sauce, 10% vinegar, 10% coke, 10% Cheongha, 10% Soju, completely burned out, raw, normal roasted, dried, and boiled) employed for beef traceability system. Completely burned out meat could not yied useful DNA in the sample, hence wa not analysed. The amplified peaks in most of the samples appeared equally barring completely burned out meat. However, roasted beef after ripened in soy sauce showed new peaks or deletion of a peaks with two markers. The DNA allele height and the amount of extracted DNA in roasted beef after ripening in 10% Cheongha was found to be higher than those in the raw beef. No significant correlations between DNA allele height and the amount of extracted DNA within the samples was noticed. Also, these results suggest that beef traceability using microsatellite (MS) markers is possible in various roasting beef because of bovine specific MS markers. Therefore, beef traceability system by DNA identify test would give the confidence in food safety and beef distribution system to customers.
        4,000원
        17.
        2010.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Analysis of meat quality grade based on the DNA identity test samples were done on 320 Hanwoo (Korean cattle) raised in Gyeonggi region of Korea. 62.29% of cows and 91.35% of steers showed high quality which was above 1st beef grade. However, differences were observed between Gyeonggi Hanwoo and total slaughtered Hanwoo in Gyeonggi in the year 2009, though the sampling was entirely based high quality meat. Meat samples of pedigree registered cattle showed high rate of above 1st meat grade compared to advanced and fundamentally registered cattle. Pedigree registry is associated with quality grade of beef like the sex of cattle. Appearance rate of above 1st beef grade in offsprings of the top 9 Korean Proven Bulls produced through mating to Gyeonggi Hanwoo was 43.27% which was found to be higher than the average grade in cows (47.3%) and was 13.08% higher than the average grade in steers (77.49%). Our results showed superior genetic characters of Korean Proven Bulls which favors and influence the meat quality grade of their offsprings. Furthermore, our results claim that sex of Hanwoo irrespective of pedigreed or Korean Proven Bulls affects and/or influence the meat quality. Conclusively, the results could therefore be used as a basic data for the improvement of beef quality. However, paternity test by DNA typing and huge sample needs to be analysed to authenticate the findings.
        4,000원
        18.
        2010.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Beef traceability, a system that provides all the records of beef production, helps customers purchase that they get to know detailed information of the Hanwoo beef. This study was carried out to investigate the DNA identity possibility in various cooking methods to ripen meat (soy sauce, gochujang sauce, 10% vinegar, 10% coke, 10% Cheongha, 10% Soju, raw, dried, and decayed) for beef traceability. The DNA content of decayed beef was higher than those of other cooking methods. It is thought that result of mixed pollutant, it did not affect amplified DNA allele height because of bovine specific microsatellite (MS) markers. The ripened sample in 10% vinegar 3 days was lowest a mount of extracted DNA (156 ng) and amplified DNA allele height (based on the raw samples to 38%) by MS markers compared with the other cooking methods. There are no significant correlation between amplified DNA allele height and the amount of extracted DNA. Therefore, beef DNA identity test in various cooking methods to ripen meat can used by bovine specific MS markers. Beef traceability system by DNA identify test will give more confidence in food safety to customers
        4,000원
        19.
        2010.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, the analysis of meat quality grade was carried out on the DNA identity test samples of 452 Hanwoo (Korean cattle) raised in Gyeongnam region in the year 2009. Appearance rate of above 1st grade from cow (70%) and steer (93.16%) showed high quality grade. On the other hand, there were the difference between this study and slaughtered Hanwoo in Gyeongnam in the year 2009 - appearance rate of above 1st grade from cow (58.77%) and steer (82.99%). It expect considered influence of the samples for beef DNA identity test that collected mainly high quality meat. Quality grade by registry classification about collected samples showed correlation between pedigree classification and quality grade that appearance rate of above 1st grade highly observed pedigree registry more than advanced registry, advanced registry than fundamental registry. Although limited to DNA identity test samples, KPN (Korean Proven Bull's Number) 452 and KPN 407 was preferred for breeding in Gyeongnam. Also average appearance rate of above 1st grade in offsprings of the top 10 Korean Proven Bulls used mating is 95.35%. It means that Korean Proven Bulls influence meat quality of offsprings positively. Thus, this analysis is expected to be a base data for the improvement of meat quality of Hanwoo raised in Gyeongnam region.
        4,000원
        20.
        2000.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        인공폐는 실제 폐의 기능을 대행하는 장치이며, 주요 기능은 정맥혈에서 이산화탄소를 제거하고 산소를 첨가하여 동맥혈화하여 개심수술시 신체의 모든 조직에 충분한 양의 동맥혈을 공급한다. 또한 체외순환 생명보조장치(ECLS 또는 ECMO)는 심한 호흡부전증에 일반적으로 이용되지만 미래의 폐 이식에 사용될 것이다. 현재 미세다고엉 폴리프로필렌 중공사를 사용하고 있는 막형 인공 폐는 두 가지 문제가 있다. 환자의 체계적인 항응고가 필요하며, 오랜 기간의 사용은 막을 통하여 혈액 쪽에서 가스 쪽으로 혈청 누출을 일으킨다. 본 연구는 미세다공성 폴리프로필렌(PP)막에 폴리디메틸실록산(PDMS)을 적충한 PP/PDMS막을 제조하고, 폴리프로필렌 막에서 유발하는 혈청 누출을 최소화하는 기술에 대하여 연구하였다. Lee-White법에 의한 whole blood의 혈전형성 실험 후 사용된 막의 기체 투과도는 PP막에서는 크게 저하되었지만, PP/PDMS막에서는 거의 동일하게 유지되었다. 그러므로 PP막에서 유발되는 혈청 누출을 PP/PDMS막에서는 해결할 수 있었다. 또한, PP/PDMS막에서는 이산화탄소의 기체토과율이 산소보다 11.5배였다.
        4,000원
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