• Explosives and Blasting
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• v.9 no.1
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• pp.3-13
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• 1991

The cautious blasting works had been used with emulsion explosion electric M/S delay caps. Drill depth was from 3m to 6m with Crawler Drill ${\phi}70mm$ on the calcalious sand stone (soft -modelate -semi hard Rock). The total numbers of test blast were 88. Scale distance were induced 15.52-60.32. It was applied to propagation Law in blasting vibration as follows. Propagtion Law in Blasting Vibration $V=K(\frac{D}{W^b})^n$ were V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites(m) W : Maximum charge per delay-period of eight milliseconds or more (kg) K : Ground transmission constant, empirically determind on the Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents where the quantity $\frac{D}{W^b}$ is known as the scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagorized in three groups. Cubic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge Per delay Plots of peak particle velocity versus distoance were made on log-log coordinates. The data are grouped by test and P.P.V. The linear grouping of the data permits their representation by an equation of the form ; $V=K(\frac{D}{W^{\frac{1}{3}})^{-n}$ The value of K(41 or 124) and n(1.41 or 1.66) were determined for each set of data by the method of least squores. Statistical tests showed that a common slope, n, could be used for all data of a given components. Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom over loom distance because the frequency is verified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30m ------- under l00m ${\cdots\cdots\cdots}{\;}41(D/sqrt[2]{W})^{-1.41}{\;}{\cdots\cdots\cdots\cdots\cdots}{\;}A$ Over 100m ${\cdots\cdots\cdots\cdots\cdots}{\;}121(D/sqrt[3]{W})^{-1.66}{\;}{\cdots\cdots\cdots\cdots\cdots}{\;}B$ where ; V is peak particle velocity In cm / sec D is distance in m and W, maximLlm charge weight per day in kg K value on the above equation has to be more specified for further understaring about the effect of explosives, Rock strength. And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

• The Korean Journal of Archival Studies
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• no.34
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• pp.221-250
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• 2012

This paper introduces the characteristics of the records and archives management of Korea from Joseon dynasty to now. This paper also explains historical background of making the records and archives management in Joseon dynasty. This paper introduces the process of establishment of modern records management system by adopting records management system and public administration of USA after liberation in 1945. The Joseon bureaucrats established systematic methodologies for managing and arranging the records. Jeseon dynasty managed its records systematically since it was a bureaucratic regime. It is also noticeable that the famous Joseonwangjosilrok(Annals of Joseon dynasty) came out of the power struggles for the control of the national affairs between the king and the nobility during the time of establishment of the dynasty. Another noticeable feature of the records tradition in Joseon dynasty was that the nobility recorded their experience and allowed future generations use and refer their experiences and examples when they performed similar business. The records of Joseon period are the historical records which recorded contemporary incidents and the compilers expected the future historians evaluate the incidents they recorded. In 1894, the reformation policy of Gaboh governments changed society into modernity. The policy of Gaboh governments prescribed archive management process through 'Regulation(命令頒布式)'. They revised the form of official documents entirely. They changed a name of an era from Chinese to unique style of Korean, and changed original Chinese into Korean or Korean-Chinese together. Also, instead of a blank sheet of paper they used printed paper to print the name of each office. Korea was liberated from Japanese Imperialism in 1945 and the government of Republic of Korea was established in 1948. In 1950s Republic of Korea used the records management system of the Government-General of Joseon without any alteration. In the late of 1950's Republic of Korea constructed the new records management system by adopting records management system and public administration of USA. However, understanding of records management was scarce, so records and archives management was not accomplished. Consequently, many important records like presidential archives were deserted or destroyed. A period that made the biggest difference on National Records Management System was from 1999 when was enacted. Especially, it was the period of President Roh's five-year tenure called Participation Government (2003-2008). The first distinctive characteristic of Participation Government's records management is that it implemented governance actively. Another remarkable feature is a nomination of records management specialists at public institutions. The Participation Government also legislated (completely revised) . It led to a beginning of developing records management in Republic of Korea.

• (The)Study of the Eastern Classic
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• no.49
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• pp.225-260
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• 2012

The poetry of Haseo Jo Gyeong is first characterized by its fantasy content with mysterious and strange beings such as mountain wizards, gods of flowers, ghosts, Jujos and dragons. Such works imply the huge gap between his political ideal of Neo-Confucianism and the reality of society and are expressions of his resulting sorrow. Of course, he did not just look at reality pessimistically. Like other Neo-Confucianism scholars, he used the symbol of "spring" in his poems, which indicates that he did have optimistic belief in the world in spite of despair. In his poems, the symbol of "spring" implies the political world where the noble man grabbed the power and the sinister groups were extracted or the world where the political ethics of Neo-Confucianism was implemented. His works depicting the essence of natural objects, mountains, and rivers exhibit the characteristics of his poetry more clearly. He described the law of the universe behind natural objects and the vibrant aspects of natural objects by depicting their movements in a clear and sharp manner. Unlike the old Neo-Confucianism scholars that often created poems on the topic of acquirement of natural law and nature, he expanded his poetic world in a direction of revealing the secrets of objects. His works describing the spirit of mountains and rivers are especially noteworthy in that they implied a life attitude of moving forward in an deteriorating world bravely by manifesting strong and dynamic power. Paying attention to the secrets of natural objects, Haseo displayed his life ideal in richer ways by painting the new forms of ume flowers. Unlike the old ume flowers poems in the past, his ume flowers poems present ume flowers as ascetics that obtained truth, men of virtue that inspired contemporary people, or retired gentlemen that revealed the profound secrets of nature. While it is unique that he manifested the forms of ume flowers in ascetics and men of virtue while perceiving the dark reality of society, it is more noteworthy that he described ume flowers as the beings revealing the profound secrets of nature. It was the expression of his yearning for an innocent personality and his fear for losing the personality, clearly depicting a human form of his ego. He created a more human and realistic personality ideal by embracing the contemporary thinking based on the profound secrets of nature in his Dohak poetry[道學詩], which is a significant achievement in that it showed new changes to Dohak poetry in the 18th century.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.1
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• pp.85-92
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• 2015

This article presents the dynamic instability response of sigmoid functionally graded material plates on elastic foundation using the higher-order shear deformation theory. The higher-order shear deformation theory has ability to capture the quadratic variation of shear strain and consequently shear stress through the plate thickness. The governing equations are then written in the form of Mathieu-Hill equations and then Bolotin's method is employed to determine the instability regions. The boundaries of the instability regions are represented in the dynamic load and excitation frequency plane. The results of dynamic instability analysis of sigmoid functionally graded material plate are presented using the Navier's procedure to illustrate the effect of elastic foundation parameter on dynamic response. The relations between Winkler and Pasternak elastic foundation parameter are discussed by numerical results. Also, the effects of static load factor, power-law index and side-to-thickness ratio on dynamic instability analysis are investigated and discussed. In order to validate the present solutions, the reference solutions are used and discussed. The theoretical development as well as numerical solutions presented herein should serve as reference for the dynamic instability study of S-FGM plates.

• The Journal of Art Theory & Practice
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• no.15
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• pp.7-30
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• 2013

This is a study on the ecological view of Robert Smithson's reclamation projects. Smithson was a pioneer of Earth art in the late 1960's. Robert Smithson believed that he could transform industrial wastelands, such as an abandoned oil rig and a no longer used quarry, into "Earth Art." In the early seventies, he conceived of land reclamation as a new art form and called this art "Reclamation Projects." His attention regarding industrial ruin started from the American political and social situations in the 1960's. In the late 1960's, American society was in chaos from the right of movement of African Americans, the women's rights movement and from the strike for renunciation of the Vietnam War. The intellectual class seemed to believe that it was the destiny of a closed system's society to run in the direction of entropy. Smithson, who was skeptical about the system of American society, also thought that entropy was the proper diagnosis to describe America's situation in the 1960's. The 1960's civic movements like the civil rights movement and antiwar movements expanded into the environmental movements based on ecological views of the 1970's. The government had also started to worry about environmental pollution. Thus, the reclamation act was also established in 1972. Smithson believed that the relation between art and social background are closely related and affect each other. He was concerned with how art can join society, and the result was reclamation projects. Such reclamation projects lie on man-made wastelands, like abandoned oil rigs and no longer used quarries, which was an allegory of entropy. He also thought that Frederick Law Olmsted was a pioneer of earth art. The aesthetic category of Olmsted's view of landscape is to be based on the picturesque of Uvedale Price and William Gilpin. So Smithson, who considered Olmsted as his touchstone, also accepted the picturesque. Such reclamation projects aim to change with nature by adapting the creative power of artists to the ruin which has the highest level of entropy in industrial society. Smithson wanted this to become the bridge between man and nature. His reclamation project's aim, which shows the system interacting between man and nature as a network, is not different from the ecological view of the 1970's environmental movement.

• Journal of the Korea Concrete Institute
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• v.15 no.5
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• pp.662-669
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• 2003

Recently, the serviceability and durability of concrete structures under thermal load have received great attention. The thermal stress and clacking behavior of concrete at early ages are one of the important factors that affect such serviceability and durability of concrete structures. Nevertheless, most studies on the behavior of early-age concrete have been confined to the temperature and strain development itself in the laboratory. The desirable efforts to explore the material properties of concrete at early-ages have not been made extensively so far. The purpose of the present study is, therefore, to identify some important material properties that affect the stress behavior of concrete at early-ages. To this end, full-scale concrete base-restrained wall members have been fabricated, and many sensors including thermocouples, strain meters and stress meters were installed inside of the wall members. These sensors were to measure the development of temperatures, strains and stresses at several location in concrete walls during the hardening and curing phase of early-age concrete. By using these measured values of strain and stress, the compliance function at early-age was identified. The basic form of compliance function derived in this study follows the double-power law. However, the results of present study indicate that the values of existing compliance functions are much lower than actual values, especially at very early-ages. It can be seen that the prediction of stresses of early-age concrete based on the proposed compliance function agrees very well with test data. The present study allows more realistic evaluation of varying stresses in early-age concrete under thermal load.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.138-144
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• 1997

A new biopolymer YU-122 from Metarrhizium anisopliae (Metschn.) Sorok consisting of glucose and galactose was tested for its physical properties and flow behavior characteristics. Xanthan gum showed slightly higher viscosity than biopolymer YU-122. Viscosity of biopolymer YU-122 at various pHs and temperatures was also tested. The viscosity of biopolymer YU-122 was very stable up to pH 11 and $60^{\circ}C$, indicating that it has a great possibility for the application such as food additives, emulsifier, and drug release agents. Flow behavior index (n) from Power Law equation is 0.173. Biopolymer YU-122 solution was a pseudoplastic non-Newtonian fluid, which indicated that it had one or more side chains. When biopolymer YU-122 was used as a emulsifier, it stabilized the emulsion up to 120 hours, which was much better than xanthan gum. The biopolymer YU-122 could form an excellent but less clear film compared with xanthan and pullulan.

• Korea-Australia Rheology Journal
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• v.18 no.2
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• pp.67-81
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• 2006

Using a strain-controlled rheometer, the dynamic viscoelastic properties of aqueous xanthan gum solutions with different concentrations were measured over a wide range of strain amplitudes and then the linear viscoelastic behavior in small amplitude oscillatory shear flow fields was investigated over a broad range of angular frequencies. In this article, both the strain amplitude and concentration dependencies of dynamic viscoelastic behavior were reported at full length from the experimental data obtained from strain-sweep tests. In addition, the linear viscoelastic behavior was explained in detail and the effects of angular frequency and concentration on this behavior were discussed using the well-known power-law type equations. Finally, a fractional derivative model originally developed by Ma and Barbosa-Canovas (1996) was employed to make a quantitative description of a linear viscoelastic behavior and then the applicability of this model was examined with a brief comment on its limitations. Main findings obtained from this study can be summarized as follows: (1) At strain amplitude range larger than 10%, the storage modulus shows a nonlinear strain-thinning behavior, indicating a decrease in storage modulus as an increase in strain amplitude. (2) At strain amplitude range larger than 80%, the loss modulus exhibits an exceptional nonlinear strain-overshoot behavior, indicating that the loss modulus is first increased up to a certain strain amplitude(${\gamma}_0{\approx}150%$) beyond which followed by a decrease in loss modulus with an increase in strain amplitude. (3) At sufficiently large strain amplitude range (${\gamma}_0>200%$), a viscous behavior becomes superior to an elastic behavior. (4) An ability to flow without fracture at large strain amplitudes is one of the most important differences between typical strong gel systems and concentrated xanthan gum solutions. (5) The linear viscoelastic behavior of concentrated xanthan gum solutions is dominated by an elastic nature rather than a viscous nature and a gel-like structure is present in these systems. (6) As the polymer concentration is increased, xanthan gum solutions become more elastic and can be characterized by a slower relaxation mechanism. (7) Concentrated xanthan gum solutions do not form a chemically cross-linked stable (strong) gel but exhibit a weak gel-like behavior. (8) A fractional derivative model may be an attractive means for predicting a linear viscoelastic behavior of concentrated xanthan gum solutions but classified as a semi-empirical relationship because there exists no real physical meaning for the model parameters.

• Journal of Navigation and Port Research
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• v.39 no.3
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• pp.217-222
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• 2015

In this research, sea routes of domestic coaster liners between 2005 and 2013 were studied via social network analysis. Study of the sea routes revealed that they follow power-law in a scale-free form, a characteristic found often in social network. We have looked into centrality, which is a major standard in the field of social network analysis. We have also analyzed the annual changing trend in the centrality of the connectivity, examined the effect of quantity through the comparison with the original quantitative analysis method, and lastly, verified the relationship between the centrality of connectivity and mediation. Then, we were able to identify ports according to priority using these factors. This research assumed and interpreted the coaster liners route as a single network and suggested useful results. Based on these results, directing of development of domestic coaster liners route development and other factors will be achieved more smoothly. And if we utilize social network analysis method in other various fields - for example, the centrality of airport and the diplomatic realations analysis of the neighboring country - we will be able to effectively analyze events in diverse perspectives.

• The Journal of Korean Medicine
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• v.18 no.1
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• pp.126-142
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• 1997

For last four or five years, the number of Korean students have gone on increasing awfully. After the year 1997 when they will flow in, our field and government will be undergone a big shock and social problems. Therefore, thorough grasping and the method of provision is expeced to need. 1. The situation, According to the data published from the year 1993 to 1997, their results are great different. But recent Korean embassy in China examined the situation of the Korean students, whose result was investigated as follows: about 1500 persons, their average age is 24 to 44, the ratio of male and female students is 3 to 1, that of their academic background which is a graduate of university : that of college : that of highschool is 1.6 : 1 : 4.7, and that of their class attitude which is direct : common : indirect appears the percents 30.4 : 52.8 : 16.8. 2. The controversial points (1) A lowering of standards on Chinese medical treatment is expected by the imprudent studying abroad without qualification. And because of excessive production of herb doctors, the amount of treatment may be above people's demand. Besides owing to the impossibility of prediction on the number the counterplans of our government may fall into utler confusion. (2) The curriculum, the teaching schedule and contents are so different that the graduates seem not to be given real education of chinese medicine from the point of Korean view. (3) In the wrong national examination, the important thought of china, and the system of WTO in Korea, when China will become mighty rival above problems contain the negative sides. 3. The counterplans - what should be performed soon. (1) Illegal contents about studying abroadl in China ought to inform sidely that students might not go on increasing. Before they form nam-power, the government and the field of chinese medicine should cope with such a situation together. (2) The law of regulation about agents should be legislated and they should be surpervised. (3) The exact numbers of students, their situation, and the present condition of each university should be examined. (4) After investigating the problems of the present system of national test, its enforcement and many counterplans is requisite. (5) The cooperating confrontation with the conference of dentistry is in need. (6) Since the problems are possibility to be developed to diplomatic questions, the effort of both nations is needful. - what need middle of long time. (1) The effort that suppress the more establishment of the college of oriental medicine is necessary. (2) After comparing with the system of foreign test, the government should make the system of test in accord with the mutualism and the principle of indiscrimination among nations and cope with such a many issues thoroughly.