• 한국자기학회지
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• 제5권5호
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• pp.351-353
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• 1995

The physical origins of anomalous volume effect (Invar effect) and elastic effect (Elinvar effect) are critically examined. We found that, unlike the volume effect, the shear elastic properties are not much influenced by the ferromagnetic transition. This finding shows that the two anomalies originate from different physical origins, thus contradicting the conventional wisdom. We discuss the consequences of this finding in the light of recent experiments.

• Computers and Concrete
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• 제8권6호
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• pp.647-675
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• 2011

Our ability to predict hydration behavior is becoming increasingly relevant to the concrete community as modelers begin to link material performance to the dynamics of material properties and chemistry. At early ages, the properties of concrete are changing rapidly due to chemical transformations that affect mechanical, thermal and transport responses of the composite. At later ages, the resulting, nano-, micro-, meso- and macroscopic structure generated by hydration will control the life-cycle performance of the material in the field. Ultimately, creep, shrinkage, chemical and physical durability, and all manner of mechanical response are linked to hydration. As a way to enable the modeling community to better understand hydration, a review of hydration models is presented offering insights into their mathematical origins and relationships one-to-the-other. The quest for a universal model begins in the 1920's and continues to the present, and is marked by a number of critical milestones. Unfortunately, the origins and physical interpretation of many of the most commonly used models have been lost in their overuse and the trail of citations that vaguely lead to the original manuscripts. To help restore some organization, models were sorted into four categories based primarily on their mathematical and theoretical basis: (1) mass continuity-based, (2) nucleation-based, (3) particle ensembles, and (4) complex multi-physical and simulation environments. This review provides a concise catalogue of models and in most cases enough detail to derive their mathematical form. Furthermore, classes of models are unified by linking them to their theoretical origins, thereby making their derivations and physical interpretations more transparent. Models are also used to fit experimental data so that their characteristics and ability to predict hydration calorimetry curves can be compared. A sort of evolutionary tree showing the progression of models is given along with some insights into the nature of future work yet needed to develop the next generation of cement hydration models.

• Advances in Traditional Medicine
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• 제7권1호
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• pp.26-33
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• 2007

Genetic polymorphism and molecular authentication were investigated with the commercial medicinal herb, Peony (Paeonia spp.), using random amplified polymorphic DNA (RAPD) markers. To identify the polymorphism of the RAPD patterns among plant origins, 20 different random primers were applied to the genomic DNA extracted from Paeonia spp. plants such as Paeonia (P.) lactiflora, P. officinale and P. japonica. Ten primers out of 20 primers could be used to discriminate the plant species in the same genus and 72 out of 81 scored DNA fragments (88.9%) generated with these primers were polymorphic. Especially, four primers, such as OPA1, OPA3, OP9, and OPA13, were useful to discriminate the plant origins among the species of Peony. In the results of cluster analysis using RAPD data obtained from the 10 primers, Peony (Paeonia spp.) plants used in this study were grouped into the two distinctive clusters, genetically. Herb medicine, especially P. lactiflora, were easily identified, when species-specific primers were applied to the investigation for discriminating herb medicine currently traded in domestic herb market, Kyungdongmart. Consequently, RAPD analysis was useful method to discriminate plant origins and the commercial medicinal herbs, Paeonia spp..

• 복식
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• 제45권
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• pp.85-102
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• 1999

The purpose of this study is reviewing and researching the origins of knitwear the history of patterned knits. Aithough historians know little about the origins of knitting many believe it was practiced as early as the 4th century by nomads roaming North Africa. later Arab raders adopted the craft which helped then while away the hours as they traveled across deserts in camel carabans, Its origins lie in the need for close-fitting and elasticated covering for the body in particular the head hand and feet. it first developed in the Mediterranean countries and later in Central and particularly Northern Europe. Early evidence of multicolored knitting is said to date back to the Egyptian Copts of 600-800 A.D. medieval knitting is developed through the Church and monastery. The increasing demand for knitted products already observable in the fourteenth and fifteenth centries and the number of preserved knitted articles increases inexcavated materialos from Europe. The improvements in technique stimulated the developement of the hand knitting industry in the early sixteenth century. The best-known source of production is the guild organization and their mass production consisted of the carpets cushion coverings and other small items for furnishing interiors but mainly of clothing. The demand for knitted goods was such that in the late sixteenth century it was mechanised, The knitting frame invented in 1589 by William Lee English priest was the most perfect machine of this period. The mass production of fully-fashioned and seamless garments in the late nineteenth and twentieth century was dangerously competitve to traditionally woven and sewn cloth in. As fashions changed knitwear has had an almost continuous ruse in public favour and the popularity of sports has encourage the fashion for flexible easy-fitting and absorbent garments.

• 한국식품조리과학회지
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• 제22권3호통권93호
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• pp.299-306
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• 2006

The numerous varieties of coffee beans contain a wide range prices and qualities. While the varieties of green coffee beans can generally be distinguished by their appearance, this visual criterion is impossible after the roasting process. Therefore, we need to develop a classification method or device. In this study, the potential of a new type of electronic nose, fast gas chromatography based on a surface acoustic wave sensor(SAW), was evaluated for the classification of origins and blended commercial brands in roasted coffee beans. Eight blended commercial brands and the origins of four similarly roasted ground coffee beans(with no significant difference of color) were rapidly(90 sec/sample) classified. The reproductive results were easily understandable over the aroma image pattern by $VaporPrint^{TM}$. In conclusion, GC-SAW electronic nose can be applied to the classification of origins and commercial brands in roasted ground coffee beans and to e evaluation of the similarities and differences of volatile pattern between samples.

• 한국산학기술학회논문지
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• 제7권5호
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• pp.930-934
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• 2006

홍제천 유역의 평창 배수분구를 대상으로 강우시 발생하수의 특성을 파악하기 위해 유량 및 수질 조사를 수행하였고, 강우유출수를 기저하수, 강우, 지붕유출수, 도로유출수, 관내 퇴적물 등 오염원별로 분석하여 기원별 초염기여도를 파악하였다. 강우시 발생초기의 오염물질의 농도는 초기세척현상에 의해 비강우시 농도의 3-10배 이상 높게 나타났으나, 강우 후반기에는 희석에 의해 비강우시 평균 농도 보다 오히려 낮은 농도를 보이는 것으로 나타났다. 오염부하의 오염원별 기여도 분석에서 관거 퇴적물에 의한 오염도가 전체 오염도에서 COD의 경우 54.6%를, SS은 73.3%를 차지하여, 가장 높은 기여도를 보여 관거 내 퇴적물의 준설과 세정을 통하여 상당량의 오염부하를 저감시킬 수 있는 것으로 나타났다.

• 대한영상의학회지
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• 제82권3호
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• pp.743-748
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• 2021

추골동맥의 기시부 변이의 다양성은 여러 문헌에서 보고되어 왔다. 그러나, 양측 추골동맥이 직접 대동맥궁으로부터 기시하는 변이는 매우 드물다. 이번 증례는 갑작스럽게 발생한 우측 편마비를 주소로 내원한 60세의 남자 환자에서 우연히 발견된 드문 양측 추골동맥 기시부의 변이를 보여준다. CT 혈관조영술에서 우측 추골동맥은 대동맥궁의 좌측 쇄골하정맥의 원위부에서 기시하였고, 좌측 추골동맥은 대동맥궁의 좌측 총경동맥과 쇄골하정맥의 사이에서 기시하였다. 이 변이와 연관이 있을 수 있는 발생학적인 기전도 고찰하였다. 추골동맥 기시부의 드문 변이의 가능성은 추골동맥이 일반적인 위치에서 보이지 않을 때 고려되어야 한다. 이 변이를 이해하는 것은 혈관 내 치료나 수술 중에 예기치 않은 합병증을 피하기 위해 중요하다.

• Journal of Microbiology
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• 제44권1호
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• pp.83-91
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• 2006

The sudden appearance and potential lethality of severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV) in humans has resulted in a focusing of new attention on the determination of both its origins and evolution. The relationship existing between SARS-CoV and other groups of coronaviruses was determined via analyses of phylogenetic trees and comparative genomic analyses of the coronavirus genes: polymerase (Orflab), spike (S), envelope (E), membrane (M) and nucleocapsid (N). Although the coronaviruses are traditionally classed into 3 groups, with SARS-CoV forming a $4^{th}$ group, the phylogenetic position and origins of SARS-CoV remain a matter of some controversy. Thus, we conducted extensive phylogeneitc analyses of the genes common to all coronavirus groups, using the Neighbor-joining, Maximum-likelihood, and Bayesian methods. Our data evidenced largely identical topology for all of the obtained phylogenetic trees, thus supporting the hypothesis that the relationship existing between SARS-CoV and group 2 coronavirus is a monophyletic one. Additional comparative genomic studies, including sequence similarity and protein secondary structure analyses, suggested that SARS-Co V may bear a closer relationship with group 2 than with the other coronavirus groups. Although our data strongly suggest that group 2 coronaviruses are most closely related with SARS-CoV, further and more detailed analyses may provide us with an increased amount of information regarding the origins and evolution of the coronaviruses, most notably SARS-CoV.

• Asian-Australasian Journal of Animal Sciences
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• 제22권8호
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• pp.1085-1090
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• 2009

There are currently five primary breeds of Chinese gamecock, the Henan, Luxi, Tulufan, Xishuangbanna andZhangzhou. Though there is historical evidence of cockfighting in China dating as far back as 2,800 years, the origin and genetic relationships of these breeds are not well understood. We used sequence variation from the mtDNA cytb gene and control region (1,697 bp) to examine the domestication history and genetic relationship of the Chinese gamecock. From 75 samples (14-16 per breed) we found 34 haplotypes, and 45 variable nucleotides. Phylogenetic reconstruction indicated multiple origins of the gamecock breeds. The breeds in the north and center of China, Tulufan, Luxi and Henan, clustered together in a haplogroup and may have the same ancestor. However the southern breeds, Zhangzhou and Xishuangbanna clustered into two isolated haplogroups, suggesting another two origins of Chinese gamecock. Meanwhile, extensive admixture was also found because samples from different breeds, more or less, were always grouped together in the same clades. Based on these results, we discuss the possibilities of multiple origins of gamecock breeds, from both ancestral gamecocks as well as other domestic chickens and red jungle fowl.

• 천문학회보
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• 제37권1호
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• pp.101.1-101.1
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• 2012

Interplanetary dust particles are observable as zodiacal light, which is the sunlight scattered by the interplanetary dust particles. The origins of interplanetary dust particles are still in question because they are eroded by Poynting-Robertson photon drag and mutual collisions among dust particles. The small-scale structures in the zodiacal light provided a clue to specify their origins. Asteroidal debris were detected as band-like structures (dust bands), and the cometary large particles were detected as narrow trails (dust trails). However, little is confirmative about their detailed origins and mineralogical compositions because of the lack of observational data particularly in the optical wavelength. We made a high-resolution optical zodiacal light map based on the CCD observations at Mauna Kea, Hawaii. We analyzed data taken on November 12, 2004. After the data reduction, such as flat fielding and subtraction of airglow emissions, we succeeded in the construction of the zodiacal light map with the spatial resolution of 3' in the solar elongation between 45 degree and 180 degree. This is the highest resolution map in the visible wavelength so far. In this map, we confirmed the dust bands structures near the ecliptic plane. We will discuss about the similarities and the differences between optical and infrared dust bands.