• Steel and Composite Structures
• /
• v.46 no.1
• /
• pp.1-13
• /
• 2023

Elastic bending of imperfect functionally graded sandwich plates (FGSPs) laying on the Winkler-Pasternak foundation and subjected to sinusoidal loads is analyzed. The analyses have been established using the quasi-3D sinusoidal shear deformation model. In this theory, the number of unknowns is condensed to only five unknowns using integral-undefined terms without requiring any correction shear factor. Moreover, the current constituent material properties of the middle layer is considered homogeneous and isotropic. But those of the top and bottom face sheets of the graded porous sandwich plate (FGSP) are supposed to vary regularly and continuously in the direction of thickness according to the trigonometric volume fraction's model. The corresponding equilibrium equations of FGSPs with simply supported edges are derived via the static version of the Hamilton's principle. The differential equations of the system are resolved via Navier's method for various schemes of FGSPs. The current study examine the impact of the material index, porosity, side-to-thickness ratio, aspect ratio, and the Winkler-Pasternak foundation on the displacements, axial and shear stresses of the sandwich structure.

• Journal of the Korean Society of Costume
• /
• v.30
• /
• pp.85-99
• /
• 1996

This study has been made to examine the symbolic meaning of our traditional costume colours based on the theory of yin-yang Wu-hsing the interaction of yin and yang with the rotation of the five agents wood firt earth metal and waters. Presenting the spirt and the life of our race the costume culture has been keep-ing its own systematic symbol. Being sensible the colour has to be under-stood as the colour sense therefore the cos-tume colour has begun to have the symbolic meaning with the feeling or the mental value. According to the theory of yin-yang wu-hsing the costume colour has presented our racial sprit way of thinking and way of life for a long time and it has become the tra-ditional culture at last. Based on the doctrine of cosmic harmony through the motion of yin and yang or the passive and active elements are their five agents form the material force of everything. The order of nature has its counterpart in five symbolic costume colours wood-blue ; fire-red: earth-yellow; metal-white: water-black. The five colours are called the primary colours. which produce the next compound colours. Accepted in the social system as well as the social stats the costume colour has set up systematically. The theory of Yin-yang Wu-hsing has given the five colours the symbolic meanings and its mainstream has been the function of Sangsaeng and Sangeuk which are genera-ted by the power of virture. The former is mu-tually beneficial while the latter destructive. The colour as a costume colour has been made distinction between the colour of the up-per classes and the colour of the middle and lower classes and the specific colour has presented the symbolic meanings. The yeollow the red and the purple have been regarded as the colour of king queen and upper classes Being the colour recognition the costume colour has been established by the society and the race generally Implied the spiritual elements the colour recognition could select the lucky colour in accordance with one's des-tiny. Besides the colour recognition has begun to appear as the racial costumes to protect the society and to pray for good fortune. According to the theory of Yin-yang Wu-hsing the costume colour has been forming through our long history and has become our costume culture. Therefore the colour of the costume has signified not only the colour sense but also the important symbolic meanings.

• Journal of the Korean Society for Library and Information Science
• /
• v.11
• /
• pp.147-183
• /
• 1984

This is an analytical study on Munheongak (文獻閣) and it's catalogue. The major objective of the study is to get a recognition of Munheongak under the culture of Sukjong (肅宗) period in Korean library history. Most of early studies made on such a category have been concentrated on Jiphyunjeon (集賢殿), Hongmungwan (弘文館), Kyujanggak(奎章閣) and their backgrounds. In this study, the author has invest gated Kungwolji (宮闕志), Munheongakseomg (文獻閣書目) and other materials related to this subject. The findings of the study can be summarized as follows: 1. Munheongak was established by king Sukjong in the 26th year of his reign. According to some records of Kungkwolji, the reason of establishment of the library was to arrange the collection in the Sango (相庫) consisted of various kinds of materials. In case of books, most of them turned out to be Korean books. 2. Munheongak was sited to the estern side of Kyunghyundang (景賢堂), which was located on the Kyungdeokgung (慶德宮). After Youngjo (英祖) the place was called Kyungheuigung (慶熙宮) so as to avoid the name of the precedent king. But these days, both the buildings are not to be found. 3. After its establishment, the library could not play the role as a library because of the then political situation and sectionalism. During the period of the revival of the learning from Youngjo till Jeongjo(正祖) the function of the library was in a stagnant state. Kyujanggak played the part in its place. 4. Referring to the collection management, the Munheongakseomog is equipped with 101 titles, 2,525 volumes, which are arranged by means of the traditional Chinese classification system. 5. The classification scheme is based on the traditional Chinese classification system which might divide all subjects into four categories such as: Confucian classics division, Historical documents division, Master's division, and Collection of literature division. Some illustrations reveal that the classification system was directly influenced by Seogoseomg (書庫書目) : the influence reflected in the classes for the translated literature and writings, poems, genealogy about kings, etc. But some subdivisions such as a class of Annals, Historical Epcerpts were omitted in the classification scheme, which did not strike the balance in the system in terms of the present theory of classification. Most of bibliographical descriptions were also influenced by Seogoseomog but some elements were partly omitted. 6. The special feature of the collection building is the absence of books in Collection of literature division except only three kinds of books in examining the Munheongakseomog. Since this is rather a comprehensive study for such aspects as historical backround, catalogue, and cultural environment of Munheongak and its related record, it is advised that further and additional research should be made.

• Steel and Composite Structures
• /
• v.18 no.1
• /
• pp.187-212
• /
• 2015

In this paper, various four variable refined plate theories are presented to analyze vibration of temperature-dependent functionally graded (FG) plates. By dividing the transverse displacement into bending and shear parts, the number of unknowns and governing equations for the present model is reduced, significantly facilitating engineering analysis. These theories account for parabolic, sinusoidal, hyperbolic, and exponential distributions of the transverse shear strains and satisfy the zero traction boundary conditions on the surfaces of the plate without using shear correction factors. Power law material properties and linear steady-state thermal loads are assumed to be graded along the thickness. Uniform, linear, nonlinear and sinusoidal thermal conditions are imposed at the upper and lower surface for simply supported FG plates. Equations of motion are derived from Hamilton's principle. Analytical solutions for the free vibration analysis are obtained based on Fourier series that satisfy the boundary conditions (Navier's method). Non-dimensional results are compared for temperature-dependent and temperature-independent FG plates and validated with known results in the literature. Numerical investigation is conducted to show the effect of material composition, plate geometry, and temperature fields on the vibration characteristics. It can be concluded that the present theories are not only accurate but also simple in predicting the free vibration responses of temperature-dependent FG plates.

• Structural Engineering and Mechanics
• /
• v.76 no.1
• /
• pp.141-151
• /
• 2020

This manuscript tends to investigate influences of nanoscale and surface energy on a static bending and free vibration of piezoelectric perforated nanobeam structural element, for the first time. Nonlocal differential elasticity theory of Eringen is manipulated to depict the long-range atoms interactions, by imposing length scale parameter. Surface energy dominated in nanoscale structure, is included in the proposed model by using Gurtin-Murdoch model. The coupling effect between nonlocal elasticity and surface energy is included in the proposed model. Constitutive and governing equations of nonlocal-surface perforated Euler-Bernoulli nanobeam are derived by Hamilton's principle. The distribution of electric potential for the piezoelectric nanobeam model is assumed to vary as a combination of a cosine and linear variation, which satisfies the Maxwell's equation. The proposed model is solved numerically by using the finite-element method (FEM). The present model is validated by comparing the obtained results with previously published works. The detailed parametric study is presented to examine effects of the number of holes, perforation size, nonlocal parameter, surface energy, boundary conditions, and external electric voltage on the electro-mechanical behaviors of piezoelectric perforated nanobeams. It is found that the effect of surface stresses becomes more significant as the thickness decreases in the range of nanometers. The effect of number of holes becomes significant in the region 0.2 ≤ α ≤ 0.8. The current model can be used in design of perforated nano-electro-mechanical systems (PNEMS).

• The Journal of Korean Philosophical History
• /
• no.36
• /
• pp.7-42
• /
• 2013

This article is on the introduction and origin of Korean Neo-Confucianism. In this article, it is verified and clarified that a scholar named Jeong, Sin-bo (鄭臣保) from Southern Song settled on today's Seosan Ganwoldo (看月島) in the year of 1237 (24th year of the king Gojong in Korean Dynasty) and he introduced the Neo-Confucianism both by Jeong, Myung-do (程明道) and Jeong, Yi-cheon (程伊川) who are also called Double Jeong to Korean scholars. Based on these facts, it overturns the history that Anhyang (安珦) first introduced Neo-Confucianism to Korean Dynasty in the year of 1290 even with 35 years ahead. When this gains official approval by the academia, the history of Neo-Confucianism seems to be rewritten. This article first examines changes in history of Korean Neo-Confucianism with three stages and then concentrates on the life of Jeong, Sin-bo. It presents that Jeong, Sin-bo was a descendant of a Southern Song's noble family named Pogang Jeong (浦江鄭氏) and he committed to Chunqiu thoughts (春秋思想) and spirit of loyalty (義理精神) naturally as the posterity of Pogang Jeong. Lastly, it also infers the transmission of Jeong, Sin-bo's scholastic mantle and his influence on the posterity.

• Publications of The Korean Astronomical Society
• /
• v.39 no.1
• /
• pp.13-26
• /
• 2024

The armillary sphere, an astronomical observation device embodying the Orbital Heaven Theory of the Later Han Dynasty in China, holds both historical and scientific significance. It has been produced in various forms by many individuals since its inception in the era of King Sejong in the Joseon Dynasty. A prominent figure in this field was Nam Byeong-cheol (南秉哲, 1817-1863), known for his work 'Uigijipseol' (儀器輯說), published in 1859, which detailed the history, production methods, and usage of the armillary sphere. This text particularly highlights 21 applications of the armillary sphere, divided into 33 measurements, covering aspects like installation, time, and positional measurements, supplemented with explanations of spherical trigonometry. Despite numerous records of the armillary sphere's design during the Joseon Dynasty, detailed usage information remains scarce. In this study, the 33 measurements described in 'Uigijipseol' (儀器輯說) were systematically classified into six for installation, nineteen for position measurement, seven for time measurement, and one for other purposes. Additionally, the measurement methods were analyzed and organized by dividing them into the ecliptic ring, moving equatorial ring, and fixed equatorial ring of the armillary sphere. In other words, from a modern astronomical perspective, the results of schematization for each step were presented by analyzing it from the viewpoint of longitude, right ascension, and solar time. Through the analysis of Nam's armillary sphere, this study not only aims to validate the restoration model of the armillary sphere but also suggests the potential for its use in basic astronomical education based on the understanding of the 19th-century Joseon armillary sphere.

• Advances in nano research
• /
• v.16 no.3
• /
• pp.231-249
• /
• 2024

When the amplitude of the vibrations is equivalent to that clearance, the vibrations for small amplitudes will really be significantly nonlinear. Nonlinearities will not be significant for amplitudes that are rather modest. Finally, nonlinearities will become crucial once again for big amplitudes. Therefore, the concrete panel system may experience a big amplitude in this work as a result of the high temperature. Based on the 3D modeling of the shell theory, the current work shows the influences of the von Kármán strain-displacement kinematic nonlinearity on the constitutive laws of the structure. The system's governing Equations in the nonlinear form are solved using Kronecker and Hadamard products, the discretization of Equations on the space domain, and Duffing-type Equations. Thermo-elasticity Equations. are used to represent the system's temperature. The harmonic solution technique for the displacement domain and the multiple-scale approach for the time domain are both covered in the section on solution procedures for solving nonlinear Equations. An effective data-driven solution is often utilized to predict how different systems would behave. The number of hidden layers and the learning rate are two hyperparameters for the network that are often chosen manually when required. Additionally, the data-driven method is offered for addressing the nonlinear vibration issue in order to reduce the computing cost of the current study. The conclusions of the present study may be validated by contrasting them with those of data-driven solutions and other published articles. The findings show that certain physical and geometrical characteristics have a significant effect on the existing concrete panel structure's susceptibility to temperature change and GPL weight fraction. For building construction industries, several useful recommendations for improving the thermo-mechanics' behavior of structural concrete panels are presented.

• (The)Study of the Eastern Classic
• /
• no.62
• /
• pp.231-262
• /
• 2016

The Jongmyo Shrine(宗廟) of Zhou dynasty was a king's main building where a diversity of rituals were held, such as 'the assembly ceremony between a king and vassals in the morning', and was also called as Taechim(太寢) Nochim(路寢) Jeongchim(正寢) and others. Before Zhou dynasty, the expressions of Taesil(太室) and Sesil(世室) were used, and especially the term of Taesil(太室) is found in the records of the early period of West Zhou. In "Seogyeong(書經)", not only the term of Nochim(路寢) but also the letter of 'chim(寢)' itself is not found at all, but the letter of 'sil(室)' appeared several times in the chapters of "Haseo(夏書)" "Sangseo(商書)" "Juseo(周書)" except for that of "Wuseo(虞書)". "Jwajowusa(左祖右社)" meaning that 'the Jongmyo Shrine(宗廟) which keeps the late king's mortuary tablet is established in the left, and Sajikdan altar(社稷壇) which enshrines a god of land and grains is established in the right' was first mentioned in the part of 'Janginyeongguk(匠人營國 : a master craftsman builds different national infrastructures, for instance, a palace and roads)' in "Donggwangogonggi(冬官考工記)" of "Jurye(周禮)". In addition, so-called 'Jwamyowusa(左廟右社)', that is, "Sajik(社稷) enshrining the god of land and grains is built in the right('右'), and the Jongmyo Shrine(宗廟) in the left('左'). (右社稷 左宗廟)" was mentioned as one of different duties of a Sojongbaek(小宗伯) in charge of ancestral rites, which was recorded in "Chungwanjongbaek(春官宗伯)" of "Jurye(周禮)". And it seems that had affected the mention of "Jwajowusa(左祖右社)" in "Donggwangogonggi(冬官考工記)" appeared thereafter. Many manners scholars including Jeonghyun(鄭玄) since Han dynasty interpreted 'Jwa(左 : left)' and 'Wu(右 : right)' here as the arrangement relation of left and right of Jongmyo(宗廟) and Sajik(社稷), but when it is interpreted as "helping(右=佑 : to help) to sacrifice to a god of land and grains in Sajik(社稷), and helping(左=佐 : to help) memorial ceremonies in Jongmyo(宗廟)." it can correspond with a 'Jongbaek(宗伯)''s duties. 'Jeonmyohuchim(前廟後寢)' is the term that began from the expression that "what's in front is called as an jongmyo shrine(宗廟) and what's back as a bedroom.(前曰廟 後曰寢)" in Jeonghyun(鄭玄)'s annotation explaining the chapter of "Hagwansama(夏官司馬)" in "Jurye(周禮)" and "Wolryeong(月令)" in "Yegi(禮記)". Chaeong(蔡邕), a figure in the same age as Jeonghyun(鄭玄), used the expression that "a court is placed in the front, and a bedroom in the back(前有朝 後有寢)." In the paper, two hypotheses were discussed about the theory about Jeonmyohuchim(前廟後寢). In one hypothesis, it expressed two facilities within a wall; 'a court in the front to deal with governmental affairs, and a comfortable interior space in the back.' In another hypothesis, it refers to two independent and separate buildings of 'an jongmyo shrine(宗廟) building in the front as the area of governmental meetings, and the residential building in the back as the residence area with family'.

• Korean Journal of Heritage: History & Science
• /
• v.45 no.2
• /
• pp.38-53
• /
• 2012

The transition process of the Balhae's capital system(都城制度) is a step-by-step marker of the completion of the state's governing system(支配體制). The most important subject in investigating the formation process of the capital of Balhae is Shanggyeongsheng(上京城). That's because Shanggyeongsheng(上京城) with a threefold-castle structure(三重城) of royal palace(宮城)-internal castle(內城)-external castle(外城) in the side-to-side checkerboard type symmetrical structure has the most paradigmatic castle structure not only in Balhae but also in East Asia. Despite the fact that such structure of Shanggyeongsheng(上京城) has a lot of similarities in the type with Sudangchangansheng(上京城) in Chungwon, scholars were skeptical that it had the same structure with Sudangchangansheng(上京城) at the time when transferring the capital. If we review the result of excavation of Shanggyeongsheng(上京城) and the findings of the senior scholars, it can be understood that Shanggyeongsheng(上京城) has not only the structure of Sudangchangansheng(上京城) but also accepted the principle of construction projected in it. It was confirmed that there is room for reconsideration on the theory of step-by-step construction(段階別築造) which was claimed based on the point that the construction like today's construction was impossible with the level of national power at that time in that the layers whose difference in construction time between the place No. 2, the central point of the royal palace, and the palaces No. 3~5 could be found were not identified, in that the whole Shanggyeongsheng(上京城) was planned by the same standard scale and finally in that there is a good possibility of accepting Samjoje(三朝制). The Shanggyeongsheng(上京城) is the result of the construction conducted by careful planning from the beginning, and with its close relation with the King Mun's(文王) policy of civilian government(文治), it shows that the governing system of the state was completed during the reign of King Mun. Therefore, the construction of the capital and the principle of construction(造營原理) projected in it are based on the premise that the Chungwon culture(中原文化) was being understood to a considerable level, and this means that the view of the world(天下觀) that he wanted to implement expanded throughout the whole Balhae.