• Journal of Food Hygiene and Safety
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• v.34 no.1
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• pp.30-39
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• 2019

An analytical method was developed for the determination of sedaxane in agricultural products using liquid chromatograph-tandem mass spectrometry (LC-MS/MS). The samples were extracted with acetonitrile and partitioned with dichloromethane to remove the interference, and then purified by using silica SPE cartridges to clean up. The analytes were quantified and confirmed by using LC-MS/MS in positive ion mode using multiple reaction monitoring (MRM). The matrix-matched calibration curves were linear over the calibration ranges ($0.001-0.25{\mu}g/mL$) into a blank extract with $r^2$>0.99. For validation, recovery tests were carried out at three different concentration levels (LOQ, 10LOQ, and 50LOQ, n=5) with five replicates performed at each level. The recoveries were ranged between 74.5 to 100.8% with relative standard deviations (RSDs) of less than 12.1% for all analytes. All values were consistent with the criteria ranges requested in the Codex guidelines (CAC/GL 40, 2003) and Food Safety Evaluation Department guidelines (2016). The proposed analytical method was accurate, effective and sensitive for sedaxane determination in agricultural commodities.

• Journal of The Korean Association For Science Education
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• v.38 no.6
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• pp.765-780
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• 2018

The purpose of this study is to synthesize the theoretical perspectives, research methods, and research results of teachers' professional vision by reviewing and analyzing previous research papers and to suggest implications for science teacher education and research. Three databases were used to search peer reviewed journal articles published between 1997-2017, which include 'teachers' and 'professional vision' explicitly in abstracts and empirical studies only. 21 articles in total were analyzed and review results are as follows. First, researchers regarded professional vision as a new concept of teacher professionalism. Previous research viewed professional vision as integrated structure of teachers' knowledge or ability activated at specific moment. Second, the analytical framework of professional vision included two aspects; 'selective attention' and 'reasoning'. Several aspects of lessons or the desirable teaching and learning factors are suggested as the subcategories of selective attention. Hierarchical levels or independent reasoning ability factors are suggested as the subcategories of reasoning process. Third, research on teachers' professional vision focused more on middle school teachers than elementary teachers and on various subject areas. Most studies used video clips and more cases of using videos of non-participants were found. In case of measurement of professional vision, most quantitative scoring methods were whether the responses of experts and teachers on video clips were consistent. Last, most studies examined or assessed teachers' professional vision. It is reported that in-service teachers' professional vision was evaluated higher than novice teachers' and using video clips were effective to examine and improve teachers' professional vision.

• Journal of The Korean Association For Science Education
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• v.39 no.3
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• pp.363-377
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• 2019

This study reveals the aspects of subjectivity in the test results in a science-specific aspect when assessing science-related affective characteristic through self-report items. The science-specific response was defined as the response that appear due to student's recognition of nature or characteristics of science when his or her concepts or perceptions about science were attempted to measure. We have searched for cases where science-specific responses especially interfere with the measurement objective or accurate self-reports. The results of the error due to the science-specific factors were derived from the quantitative data of 649 students in the 1st and 2nd grade of high school and the qualitative data of 44 students interviewed. The perspective of science and the characteristics of science that students internalize from everyday life and science learning experiences interact with the items that form the test tool. As a result, it was found that there were obstacles to accurate self-report in three aspects: characteristics of science, personal science experience, and science in tool. In terms of the characteristic of science in relation to the essential aspect of science, students respond to items regardless of the measuring constructs, because of their views and perceived characteristics of science based on subjective recognition. The personal science experience factor representing the learner side consists of student's science motivation, interaction with science experience, and perception of science and life. Finally, from the instrumental point of view, science in tool leads to terminological confusion due to the uncertainty of science concepts and results in a distance from accurate self-report eventually. Implications from the results of the study are as follows: review of inclusion of science-specific factors, precaution to clarify the concept of measurement, check of science specificity factors at the development stage, and efforts to cross the boundaries between everyday science and school science.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.834-846
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• 2017

An increase in the number of retiring experienced pilots as well as drastic graying of new pilots will raise the problems on deepening imbalance of supply and demand of pilots over the next 7 years, which could entail fatal problems for the safety of harbour pilotage. In this study, the improvement plan of legal system to ease imbalance between supply and demand of pilots and help secure more experienced pilots has been proposed. A current state survey and analysis, statistical analysis, questionnaire survey on foreign countries, in-depth consultation with experts, etc., were all carried out to support this research. The conclusions of this study are, firstly, to propose an amendment that the minimum requirement of 5 years of seagoing service as a master to sit for the pilot exam should be relaxed to 2 years(which must include at least 1 year of master's seagoing service within the most recent 5 years) but the minimum requirement of 1 year of pilotage service should be reinforced to 1 year and 6 months to obtain a higher class of pilot certificate. Secondly, it is proposed that an amendment offering an additional 1 point per year over the minimum period of 2 years of seagoing service as a master should be added, with a maximum of 10 points in order to rationalize the additional incentive point system. In order to secure experienced pilots and resolve the legal conflict between the certificate revalidation system and the retirement system, it is also proposed that an amendment be passed revoking the retirement system and limiting the validity of any new certificates only to 68 years of age when issuing or revalidating a certificate, if an applicant is over a certain age. Promotional work, such as collecting opinions from interested parties and generating positive public awareness, should be carried out in the future. It will also be necessary to conduct a study on the training pilot exam system.

• Korean Journal of Heritage: History & Science
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• v.42 no.4
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• pp.152-171
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• 2009

The Dancheong(丹靑) of the main building of Mihwangsa Buddhist Temple(美黃寺) in Haenam(海南) is the leading work of the Jeolla Dancheong style, which was created in the 18th century and has been passed down to the early modern days, and boasts its excellence and originality. On the outside, one can only see the traces of the Dancheong due to the colors that fell off and deteriorated severely. On the inside, however, the general Dancheong pattern is accompanied by the painting of 1,000 Buddhas(千佛圖), which is hardly found in other Buddhist temples, and the Arahan painting, which is truly magnificent in technique and can pass as an independent painting. The Dancheong also has unique methodological characteristics that can't be found in other Dancheong works such as the painting and attaching technique. The Dancheong inside is estimated to have been created in 1754 considering the records of "Dalmasan Mihwangsasa Daebeopdang Jungsusangryangmun(達摩山美黃寺大法堂重修上樑文)", the calligraphical writings of "Mudeungsanindanhwakya(無等山人丹?也)"and "Geonryungshipgu(乾隆十九)" left in the Jungryang, and the style characteristics reflected in the Dancheong patterns and the painting of 1,000 Buddhas. The fact that there are no traces of re-Dancheong also supports the estimation that the Dancheong was created in the absolute age of 1754. The absolute age will be the reference of deciding the chronological years of Dancheong patterns and be helpful in examining the characteristics and changes by the periods. There were certain style characteristics in Dancheong by the periods and regions. The Dancheong of Jeolla region also had its own style, which includes the tendency of finishing with two- or three-fold green belts without giving meokdanggi to the meoricho and the huge jar decoration of huigol. Treating the baetbadak of all materials, whether it's Geumdancheong or morodancheong, with lines of certain thickness and colors is another style of Jeolla Dancheong from the 18th to the 20th century. The Dancheong of the Geukrakbojeon(極樂寶殿) of Cheoneunsa Buddhist Temple and Daewoongbojeon(大雄寶殿) of Naesosa Buddhist Temple in Jeolla is especially noteworthy in that it bears similar patterns and techniques to that of the main building of Mihwangsa Buddhist Temple in addition to the characteristics mentioned above. The Dancheong of Mihwangsa Buddhist Temple must have exerted so great influences on that of the two temples that it's called "the style of Mihwangsa Buddhist Temple."When adopting a broader point of view, it can be classified as one of the Dancheong styles of Jeolla. The common icons and techniques found in the Dancheong of Mihwangsa, Cheoneunsa, and Naesosa Buddhist Temple provide some clues about the influential relationships among painters of the days. They may have been created by the painters of the same school or the painters affected by those who created the Dancheong of Mihwangsa Buddhist Temple.

• Korean Journal of Heritage: History & Science
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• v.46 no.2
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• pp.46-69
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• 2013

The results of study on the meaning landscape and environmental design techniques of the Byulup, Yoohoedang garden(Hageowon) based on the story in the collection of Kwon Yi-jin (Yoohoedangjip, 有懷堂集), are as below. First, Yoohoedang Kwon Yi-jin (有懷堂 權以鎭 : 1668~1734) constructed a Byulup garden consisting of ancestor grave, Byulup, garden, and a school, through 3 steps for 20 years in the back hill area of Moosoo-dong village, south of Mountain Bomun in Daejeon. In other words, he built the Byulup(別業, Yoohoedang) by placing his father's grave in the back hill of the village, and then constructed Yoegeongam(餘慶菴) and Geoupjae(居業齋) for protection of the pond(Napoji, 納汚池), garden(Banhwanwon, 盤桓園), and ancestor graves, and descendants' studying in the middle stage. He built an extension in Yoohoedang and finally completed the large-size garden (Hageowon) by extending the east area. Second, in terms of geomancy sense, Yoohoedang Byulup located in Moosoo-dong village area is the representative example including all space elements such as main living house (the head family house of Andong Kwon family), Byulup (Yoohoedang), ancestor graves, Hagoewon (garden) and Yoegeongam (cemetery management and school) which byulup type Byulseo should be equipped with. Thirdly, there are various meaning landscape elements combining the value system of Confucianism, Buddhism and Taoism value, including; (1) remembering parents, (2) harmonious family, (3) integrity, (4) virtue, (5) noble personality, (6) good luck, (7) hermit life, (8) family prosperity and learning development, (9) grace from ancestors, (10) fairyland, (11) guarding ancestor graves, and (12) living ever-young. Fourth, after he arranged ancestor graveyard in the back of the village, he used surrounding natural landscapes to construct Hagoewon garden with water garden consisting of 4 mountain streams and 3 ponds for 13 years, and finally completed a beautiful fairyland with 5 platforms, 3 bamboo forests, as well as the Seokgasan(石假山, artificial hill). Fifth, he adopted landscape plantation (28 kinds; pine, maple, royal azalea, azalea, persimmon tree, bamboo, willow, pomegranate tree, rose, chinensis, chaenomeles speciosa, Japanese azalea, peach tree, lotus, chrysanthemum, peony, and Paeonia suffruticosa, etc.) to apply romance from poetic affection, symbol and ideal from personification, as well as plantation plan considering seasonal landscapes. Landscape rocks were used by intact use of natural rocks, connecting with water elements, garden ornament method using Seokyeonji and flower steps, and mountain Seokga method showing the essence of landscape meanings. In addition, waterscape are characterized by active use of water considering natural streams and physio-graphic condition (eastern valley), ecological corridor role that rhythmically connects each space of the garden and waterways following routes, landscape meaning introduction connecting 'gaining knowledge by the study of things' values including Hwalsoodam(活水潭, pond), Mongjeong(蒙井, spring), Hosoo(濠水, stream), and Boksoo(?水, stream), and sensuous experience space construction with auditory and visualization using properties of landscape matters.

• Korean Journal of Heritage: History & Science
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• v.44 no.4
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• pp.112-129
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• 2011

This paper was written to understand, through the types and production techniques, how cooking vessels of Baekje Hanseong period had evolved, - the cooking vessels that were excavated from the historic sites of Baekje Hanseong Period such as Mongchontoseong and Pungnaptoseong of Seoul, the ancient tomb group of Seokchon-dong, and Misari historic site of Hanam. First, the results produced through the analysis of types of these cooking vessels are as followings: as for deep bowls, the maximum body diameter is found on the top of pottery, while as for an egg-shaped pottery, the maximum body diameter is found on the middle height of pottery. However, as for the rim diameter ratio to the neck diameter ratio of pottery, the said two typed potteries were shown to have smaller ones. In consideration of each historic site, as for deep bowls, the ancient tomb group of Seokchon-dong had potteries that had less volumes, were deeper, and had higher maximum body diameters. When it comes to an egg-shaped pottery, Pungnaptoseong had the potteries that were deeper than those of Misari historic site, and their potteries also had the maximum body diameter found on the middle height of pottery, and larger rim diameter ratio to the neck diameter of the pottery. The results produced though the analysis of the production techniques of these cooking vessels are as followings: in the case of deep bowls, as the width of a volume category gets larger, the pottery stamping with an anvil including patterns was more frequently used for pottery production. In this case, simultaneously braid patterns were frequently found on the outer sides of these potteries. In addition, it was found the basal walls of these potteries were thinnest in all typed potteries. This shows there occurred technique transitions according to the time flow. When it comes to an egg-shaped pottery as well, the pottery produced by using an anvil had the thinnest basal wall and its rim diameter ratio to its neck diameter ratio was smaller. Also around the mouth of this pottery, traces were found on its front, the traces formed by the strong rotating power. It is determined these two typed potteries were all produced by using an anvil to have thinner walls. Then, how these potteries were used? In the case of deep bowls, liquid food was put on a hearth or ground to be cooked whereas in the case of an egg-shaped pottery, the pottery was put on a puttumak(kitchen stove) mainly for boiling water. The deep bowls and egg-shaped potteries excavated from the center areas of Baekje Hanseong Period were not clearly determined about when their pastes or firing times were, but as for their production techniques, it was possible to check how they had developed. Moreover, it was determined that in the changing aspects of their production techniques, temporalite is also reflected.

• Korean Journal of Environmental Biology
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• v.37 no.1
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• pp.93-108
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• 2019

To investigate the temporal-spatial distribution of picophytoplankton in relation to different water masses in the northern East China Sea (ECS), picophytoplankton abundance were investigated using flow cytometry with environmental factors in 2016-2017. The results from the analysis of flow cytometer data showed that Synechococcus appeared across all seasons, exhibiting its minimum abundance in winter and maximum abundance in summer. Furthermore, high abundance was detected in the surface mixed layer during spring and summer when vertical stratification occurs; in particular, Synechococcus exhibited maximum abundance in thermocline layer, indicating a close correlation to water temperature and thermocline formation. In addition, the abundance of Synechococcus indicated a decrease in the western seas in 2017 compared to 2016 under the strong influence of the Changjiang Diluted Water (CDW). This was determined by the significant influence of the CDW on the abundance of Synechococcus during summer in the northern waters of the ECS. In contrast, Prochlorococcus did not appear during winter and spring, and its distribution was limited during summer and autumn in the eastern seas under the influence of the Kuroshio current. The largest range of Prochlorococcus distribution was confirmed during autumn without the influence of the CDW. Thus, the distribution pattern of each picophytoplankton genus was found to be changing in accordance to the extension and reduction of sea current in different seasons and periods of time. This is anticipated to be a useful biological marker in understanding the distribution of sea currents and their influence in the northern waters of the ECS.

• Korean Journal of Heritage: History & Science
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• v.52 no.3
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• pp.130-145
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• 2019

The palaces in South Korea are largely divided into primary palaces (法宮) and secondary palaces (離宮). In the early Joseon period, the primary palace was Gyeongbokgung Palace, and the secondary palace was Changdeokgung Palace. Additionally, there is the concept of imperial palaces (正宮). Gyeongbokgung Palace was the primary palace and the imperial palace. The topography of Gyeongbokgung is based on Mt. Baegak, which is the symbol of royal authority. The location of the palaces was chosen to highlight the king's dignity and authority. The three gates and three courts (三門三朝) were positioned on a straight line based on one axis along the ridge of Mt. Baegak to establish the legitimacy, hierarchy, and unity of the kingship. The secondary palace was built according to the demands of the king and the royal family or the political situation. It was created as a royal living space; thus, creating independent and diverse spaces along multiple axes. The primary palace was chosen to be built on the terrain of Yang, and the secondary palace was chosen to be built on the terrain of Yin; the criteria for laying buildings in the palace areas had to be different. The most important point in the formation of Joseon palaces was that the secret vital energy for the king (王氣) originated from the sacred mountain. Important elements of the palace were the secret vital energy chain of feng shui (風水氣脈) and the forbidden stream (禁川). The secret vital energy chain of feng shui was the gateway to the secret vital energy for the king, and the forbidden stream was a method of preventing the king from leaving the palace grounds. Gyeongbokgung Palace, which is on typical feng shui terrain, faithfully reflects the principles of feng shui. On the other hand, the secondary palace was built on incomplete and irregular feng shui terrain. Feng shui was part of the nature and the geography of the ruling classes in the Joseon Dynasty. By examining their geography, I believe that the perfection of traditional culture inheritance and restoration can be improved.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.289-292
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• 2019

Lachnospiraceae bacterium KGMB03038 (=KCTC 15821) belonging to the class Clostridia in phylum Firmicutes, was isolated from a stool sample of a healthy Korean. Herein, we report the complete genome sequence of strain KGMB03038 analyzed using the PacBio Sequel platform. The genome comprises of 3,334,474 bp with G + C content of 47.8%, which includes 3,099 predicted protein-coding genes, 12 ribosomal RNAs, 54 transfer RNAs, and 4 ncRNAs. Genome analysis revealed that strain KGMB03038 possesses a number of genes involved in hydrolysis of carbohydrates, including mono-, di-, and oligo-saccharides, and biosynthesis of various amino acids.