• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.162-167
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• 2020

In this study, a fatigue analysis of an external fuel tank and pylon for fixed-wing aircraft was carried out as part of the domestic development of fixed-wing aircraft. Through structural analysis, the analysis areas were selected, and the transfer function for unit loads was established in the selected parts. For each of the continuous load profiles, stress components in the selected areas were calculated using the load of each profile and the transfer function, and the Von Mises equivalent stress was employed as the representative stress of each profile. In addition, the rainflow counting technique was used to extract individual profiles obtained from the initial large load profiles and to calculate their amplitude and average values. For life evaluation, the S-N diagram of the Metallic Materials Properties Development and Standardization (MMPDS) was applied, and the damage value was calculated by Miner's rule to assess the life of the selected area. As a result of the life assessment, the life span requirement for the selected area of the external fuel tank and the pylon was assessed as being satisfied.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.8
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• pp.889-897
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• 2011

In this work, we investigated the theoretical forming limit models for Zircaloy-4 and Zirlo used for spacer grid of nuclear fuel rods. Tensile and anisotropy tests were performed to obtain stress-strain curves and anisotropic coefficients. The experimental forming limit diagrams (FLD) for two materials were obtained by dome stretching tests following NUMISHEET 96. Theoretical FLD depends on FL models and yield criteria. To obtain the right hand side (RHS) of FLD, we applied the FL models (Swift's diffuse necking, M-K theory, S-R vertex theory) to Zircaloy-4 and Zirlo sheets. Hill's local necking theory was adopted for the left hand side (LHS) of FLD. To consider the anisotropy of sheets, the yield criteria of Hill and Hosford were applied. Comparing the predicted curves with the experimental data, we found that the RHS of FLD for Zircaloy-4 can be described by the Swift model (with the Hill's criterion), while the LHS of the FLD can be explained by Hill model. The FLD for Zirlo can be explained by the S-R model and the Hosford's criterion (a = 8).

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.441-445
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• 2005

태화강 주변지역 지하수의 계절적 수질 변화를 보고자 현장측정 항목(수온, pH, 알칼리도, 전기전도도), 일반 항목(증발잔류물, 총경도, 과망간산칼륨소비량), 음이온물질$(F^-,\;Cl^-,\;{NO_3}^-,\;{SO_4}^{2-})$, 양이온물질$(Ca^{2+},\;Mg^{2+},\;K^+,\;Na^+)$등으로 구분하여 분석하였으며, 총 70개 지점을 대상으로 2004년 5월, 10월 2회에 걸쳐 실시하였다. 지역별 수질특성을 살펴보면 남구지역은 $Ca-Mg-HCO_3,\;Ca-Mg-HCO_3-Cl,\;Ca-Mg-Na-Cl-HCO_3,\;Na-Cl-HCO_3$의 4가지 유형이 전체 시료의 74%를 차지하였으며, $Ca-Mg-HCO_3$형이 가장 우세하게 나타났고, 중구지역 지하수에서는 $Ca-Mg-HCO_3-Cl,\;Ca-Mg-Na-HCO_3-Cl,\;Ca-Mg-HCO_3$의 3가지 유형이 전체 시료의 60%를 차지하는 것으로 나타났으며, 이중에서 $Ca-Mg-HCO_3-Cl$형이 가장 우세하게 나타났다. 두 지역의 수질 변화를 살펴보면. 전기전도도는 남구는 $731.5{\mu}s/m^3$에서 $529.8{\mu}s/m^3$, 중구는 $752.6{\mu}s/m^3$에서 $621.6{\mu}s/m^3$로 201.7, $131.0{\mu}s/m^3$만큼 작아져 두 지역 모두 같은 양상을 보였으나, Hardness 및 TDS의 경우 남구지역은 5월보다 10월에 평균, 최대값이 모두 낮게 나타났다. 또한 $Cl^-$의 경우 지역적, 계절적으로 큰 차이를 보이고 있으며 남구는 5월 68.2mg/l, 10월에는 61.7mg/l로 다소 감소하였으나 중구의 경우 5월 75.5mg/l, 10월 122.1mg/l로 다소 증가한 것으로 나타났다. 양이온 분포 비율 및 농도는 비슷하게 나타났으며, 계절적으로 5월보다 10월에 모두 높게 나타났다. 두 지역 모두 양이온물질 중 나트륨의 분포비율 및 농도가 5월보다 10월에 다소 높게 나타났다. 연구 지역 지하수의 계절적 수질변화를 살펴보면 두 지역간의 지하수질 및 분포특성에 있어 다소 차이를 보이고 있으며, 특히 중구 지역에서 5월보다 10월에 나트륨과 염소이온의 증가가 다소 나타나는 것으로 관찰되었다. 또한 연구지역 중 특이지점($Cl^-$:1,000mg/l이상)은 남구는 5월에 2개에서 10월에는 3개 지점으로 증가하였으며, 중구는 5월, 10월 모두 4개 지점으로 나타났다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.2
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• pp.107-116
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• 1999

To study the characters of surface sediment and to describe the seasonal depositional environment as a result of sedimentation process off Byun-San Peninsula, a total 61 samples of surface sediment (32 samples in summer; 29 samples in winter) were collected and analysed. A digitized depth data from sea chart and echosounding profiles along five trans-sections were helpful for understanding the morphological factors. The types classified by the characters of surface sediment are type I (sand, S), type II (silty sand, zS), and type ill (sandy silt, sZ). Mean grain size varies from 2.11 to 7.81 ${\Phi}$. The positive-skewness shows the typical tide-dominated environment. The sediment type of the northwestern stations is medium sand and the sorting value is 0.5~1.4 ${\Phi}$ of well/moderately sorted. Meanwhile, other stations are composed of muddy sands and sandy muds transported from rivers and offshore. These sediment types toward inshore change gradually from silty sand to sandy silt. According to the C/M diagram, there are three major transport modes of sediment: bed load (Mode A), graded suspension (Mode B), and suspension (Mode C), correlating with north-eastern sandy area, middle part of silty-sand area, and southern sandy-silt area, respectively. The result of Principal Component Analysis shows also similar pattern of sediment types. In result, sediment texture of type III tends to be finer and more poorly-sorted than that of type II and sediment facies are correlateed with sedimentation process.

• Journal of Korean Society on Water Environment
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• v.33 no.5
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• pp.511-524
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• 2017

This study was carried out for the purpose of creating a restoration plan to improve the ecological quality of the Changwon and Nam streams. Based upon the results of comprehensive diagnostic assessment, restoration priority was given to the upstream reach, where conservation status is relatively superior. Restoration level was usually determined to practice active restoration as conservation, and the states of both Changwon and Nam streams were not so good. Restoration plans, by reach, were classified into "upstream", "midstream", and "downstream" were suggested in both terms of horizontal section frame and vegetation-based on the result of diagnostic assessment and the reference information. "Upstream", "mid-stream" and the "downstream" of Changwon and Nam streams were classified into "small-gravel- mountainous", "small-sand-plain", and "small-clay-plain streams" respectively (based on scale, and substrate and slope of river bed). The spatial arrangement of vegetation was laid out in diagram form by reflecting micro-topography and the water level of the horizontal section of river. Information regarding species composition was recommended as dominant species, which appear frequently in three vegetation zones composed of herbaceous plants, shrubs and trees and sub-tree- dominated zones divided by reflecting disturbance regime, depending on position on the horizontal section of river. Moreover, there have been prepared not only plans to improve the terrestrial ecosystems around the streams but also plans to create ecological networks, which can serve to improve the ecologic quality of the whole regional environment by serving to connect streams and terrestrial ecosystems, a process probably necessary and definitely recommended to realize true (genuine) restoration. Plans for ecological parks and networks were prepared by mimicking the species composition of Alnus japanica community, Zelkova serrata community, Carpinus laxiflora community, Quercus aliena community, and Q. serrata community.

• 한국체육학회지인문사회과학편
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• v.55 no.4
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• pp.85-107
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• 2016

By examining the constitutive characteristics of Yon-Ko-Jeon and analyzing the lived meanings and experiencing essence of students, this study details the students' awareness, responses, and strategies with regards to the phenomenon of women's alienation from Yon-Ko-Jeon. Students from the two colleges were divided into two groups- one which was aware of women's alienation from Yon-Ko-Jeon, and another group that was unaware of such a phenomenon. Students without awareness tended to perceive the alienation of women from Yon-Ko-Jeon as a natural phenomenon. On the other hand, the members who had awareness tended to see it as a phenomenon that was either justified, unequal, or in need of change. In the latter group, those who saw women's alienation as a justified phenomenon responded with tolerance and adopted a bystander strategy. Conversely, those who saw it as an unequal phenomenon responded with rejection and instead chose to adopt anti-/alternative Yon-Ko-Jeon strategies. The last group, which perceived women's alienation as a phenomenon in need of change, adopted correcting responses as well as intercollegiate solidarity and cooperation strategies. A generalization of the findings reveals that the students' experiencing essence of the phenomenon extends from critical thinking to awareness, response, and strategy in a step-by-step and sequential process. Through this study, it was found that the students' experiencing essence all follow a continuous thinking pattern, as illustrated in the diagram provided.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.1
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• pp.203-215
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• 2017

Recently, interest in Pedestrian Navigation Service (PNS) is being increased due to the diffusion of smart phone and the improvement of location determination technology and it is efficient to use landmarks in route guidance for pedestrians due to the characteristics of pedestrians' movement and success rate of path finding. Accordingly, researches on extracting landmarks have been progressed. However, preceding researches have a limit that they only considered the difference between buildings and did not consider visual attention of maps in display of PNS. This study improves this problem by defining building attributes as local variable and global variable. Local variables reflect the saliency of buildings by representing the difference between buildings and global variables reflects the visual attention by representing the inherent characteristics of buildings. Also, this study considers the connectivity of network and solves the overlapping problem of landmark candidate groups by network voronoi diagram. To extract landmarks, we defined building attribute data based on preceding researches. Next, we selected a choice point for pedestrians in pedestrian network data, and determined landmark candidate groups at each choice point. Building attribute data were calculated in the extracted landmark candidate groups and finally landmarks were extracted by principal component analysis. We applied the proposed method to a part of Gwanak-gu, Seoul and this study evaluated the extracted landmarks by making a comparison with labels and landmarks used by portal sites such as the NAVER and the DAUM. In conclusion, 132 landmarks (60.3%) among 219 landmarks of the NAVER and the DAUM were extracted by the proposed method and we confirmed that 228 landmarks which there are not labels or landmarks in the NAVER and the DAUM were helpful to determine a change of direction in path finding of local level.

• (The)Study of the Eastern Classic
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• no.66
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• pp.251-276
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• 2017

This article is an attempt to identify the difference between "Oneness between Heaven and Man(天人合一)" thought proposed by Zhoudunyi(周敦?) in 'Taijirushuo(太極圖說)' and "Cheon-In-Sim-Seong-Haap-Il(A diagram about Unifying Heaven, Human, and Mind-and-Heart)(天人心性合一)" thought presented by Kwonkun(權近) in 'Ip-Hak-Do-Seol(入學圖說)'. Oneness between Heaven and Man thought, which have developed into practical ideas centered on self-cultivation theory, have a philosophical depth and logical system by Zhoudunyi(周敦?) with 'Taijirushuo(太極圖說)' in order to summarize the metaphysical cosmology and the treatise of human nature in Dynasty Song. Zhoudunyi established the concept of Wuji(無極) corresponding to Heaven(天), and suggested unified cosmology of 'Wuji(無極)-Taiji(太極)-Yin and Yang(陰 陽)-Five elements(五行)-Human(人間)-Everything(萬物)'. His cosmology is the perception that heaven, the creator of all things, is the relationship of unity, which is connected by man as the creature and the Order(命)and Nature(性). Thus, when people restores one's nature and realized that it is a mandate from Heaven, he said that heavenly unity can be realized and become a Saint(聖人). The idea of Zhoudunyi(周敦?) comes to Zhu Xi(朱熹) about 120 years later and it is concluded to be converged the Neo-Confucianism with Lichi theory. Accordingly, Zhoudunyi(周敦?) is evaluated as the master of the Neo-Confucianism to posterity. KwonKun suggested the idea of "Cheon-In-Sim-Seong-Haap-Il(A diagram about Unifying Heaven, Human, and Mind-and-Heart)(天人心性合一)" in 'Ip-Hak-Do-Seol(入學圖說)' at the end of Goryeo Dynasty. KwonKun's "Cheon-In-Sim-Seong-Haap-Il" thought is logically coherent by adding an element of the doctrines of Chu-tzu to his teacher Yi Saek's "Chun-In-Mu-Gan" and arranging that the functions of my mind and Li(理) are all together. Whereas Zhuodunyi is concerned with the creation principle of the universe and all things, KwonKun mainly cares about Heaven(天), Human(人), and Heart (心), and Nature(性) in the view of psychology. In addition, he suggested that "Cheon-In-Sim-Seong-Haap-Il" can be achieved by self-cultivation centered of Gyeong-thought(敬思想). The idea of KwonKun has become a stepping stone to the development of the doctrines of Chu-tzu based on psychology. His ideas came to Yi Hwang about 150 year later, and are integrated into four clue-seven emotion (Sadan Chiljung四端七情) thesis and Gyeong-thought(敬思想). However, unlike the Zhoudunyi, KwonKun is not properly evaluated despite his academic accomplishments.

• Journal of the Daesoon Academy of Sciences
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• v.37
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• pp.263-295
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• 2021

Until recently, academic consensus held that Zhou Dunyi's Taijitu (Taiji Diagram) originated from Cantongqi. However, a new debate has arisen wherein some scholars question that theory and related theories. They criticize these previous theories because the books and charts used as evidence in those theories were published after the lifetime of Zhou Dunyi, and this disqualifies their influence on his thought. However, identifying certain authors as being of a slightly later period than Zhou Dunyi does not definitively answer whether or not Zhou Dunyi's diagram was based on Cantongqi. I approached this problem from a different perspective. Zhou Dunyi's Taijitu is based on the system of taiji (Taiyi), yin-yang, and the five movements. Consequently, the formation of this system should be traced back historically. In the process of tracing it back, I intended to explain that the main character of Cantongqi is closely related to the formation of the system of taiji (Taiyi), yin-yang, and the five movements. The system of taiji (Taiyi), yin-yang, and the five movements was first established as a religious theological system in the Han Dynasty. In this process, yin-yang and the five movements were combined by Dong Zhongshu, and the five movements were introduced by Han Dynasty scholars as a method of interpreting the I-ching. However, Han Dynasty scholars did not form this system. In the late Han Dynasty, Cantongqi adopted the theological system of yin-yang and the five movements to theoretically form the system of taiji (Taiyi), yin-yang, and the five movements. Cantongqi was able to form this system because of the logic that yin-yang is the essence of the I-ching. Cantongqi does not have the same schematic as Taijitu. However, the system of taiji (Taiyi), yin-yang, and the five movements appears and extracts the components that make up Taijitu. Therefore, I do not think we should hastily agree with the recent claims made by scholars.

• Economic and Environmental Geology
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• v.2 no.4
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• pp.23-71
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• 1969

Sediment samples were taken at about half-mile intervals from all the inajor rivers draining the St. Austell granite mass. The minus 80 mesh(B.S.S.) fraction of each sample was analysed, using semiquantitative methods, for sodium, potassium, lithium, phosphorus, nickel, chromium, tin, tungsten, arsenic copper, zinc and lead. The work was carried out with the view to gaining further information as to the geographical distribution of such different granite facies as might axist, and to investigate the geochemical dispersion of these elements with relation to mineralisation in this area. The sesults confirm Exley's suggestion that the mass consists of two major granite intrusions, the earlier undifferentiated one is joined on the west by a later differentiated intrutive. During the work grid deviation maps proved particularly useful in obtaining data concerning the nature of the granite but frequency diagrams were not particularly helpful. All the known lode areas were associated with stream sediments containing anomalously high concentrations of lode metals and it is concluded that these high concentrations are due premarily to lode material transferred to the streams in the form of tailings lost during milling operations.