• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.112-118
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• 2005

Ball bearings which were fitted between housing and shaft play an important role in rotating shaft system smoothly, Therefore bearing's running accuracy has significant influence on that of rotating machinery. Manufacturing accuracy of bearings as well as that of shaft and housing is main factor to affect bearing running accuracy In this paper, bearing's vibration and fatigue life considering raceway roundness of ball bearing before and after being fitted into housing are theoretically estimated. To perform analysis, a simple three degrees of freedom model was proposed and then these analysis was conducted utilizing the Newton-Raphson iterative method. The results show that vibration magnitude of ball bearing fitted into housing is considerably larger than before assembly, and bearing's theoretical L$_{10}$ fatigue life that ninety percent of the bearing population will endure decreased in about fifty percent.

• Computers and Concrete
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• v.7 no.2
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• pp.159-167
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• 2010

This paper demonstrates numerical techniques for complex large-scale modeling with microplane constitutive theories for reinforced high strength concrete, which for these applications, is defined to be around the 7000 psi (48 MPa) strength as frequently found in protective structural design. Applications involve highly impulsive loads, such as an explosive detonation or impact-penetration event. These capabilities were implemented into the authors' finite element code, ParaAble and the PRONTO 3D code from Sandia National Laboratories. All materials are explicitly modeled with eight-noded hexahedral elements. The concrete is modeled with a microplane constitutive theory, the reinforcing steel is modeled with the Johnson-Cook model, and the high explosive material is modeled with a JWL equation of state and a programmed burn model. Damage evolution, which can be used for erosion of elements and/or for post-analysis examination of damage, is extracted from the microplane predictions and computed by a modified Holmquist-Johnson-Cook approach that relates damage to levels of inelastic strain increment and pressure. Computation is performed with MPI on parallel processors. Several practical analyses demonstrate that large-scale analyses of this type can be reasonably run on large parallel computing systems.

• Communications for Statistical Applications and Methods
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• v.31 no.5
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• pp.497-519
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• 2024

In reliability analysis, the probability P(Y < X) is significant because it denotes availability and dependability in a stress-strength model where Y and X are the stress and strength variables, respectively. In reliability theory, the inverse Lomax distribution is a well-established lifetime model, and the literature is developing inference techniques for its reliability attributes. In this article, we are interested in estimating the stress-strength reliability R = P(Y < X), where X and Y have an unknown common scale parameter and follow the inverse Lomax distribution. Using Bayesian and non-Bayesian approaches, we discuss this issue when both stress and strength are expressed in terms of lower record values. The parametric bootstrapping techniques of R are taken into consideration. The stress-strength reliability estimator is investigated using uniform and gamma priors with several loss functions. Based on the proposed loss functions, the reliability R is estimated using Bayesian analyses with Gibbs and Metropolis-Hasting samplers. Monte Carlo simulation studies and real-data-based examples are also performed to analyze the behavior of the proposed estimators. We analyze electrical insulating fluids, particularly those used in transformers, for data sets using the stress-strength model. In conclusion, as expected, the study's results showed that the mean squared error values decreased as the record number increased. In most cases, Bayesian estimates under the precautionary loss function are more suitable in terms of simulation conclusions than other specified loss functions.

• Bulletin of the Korean Chemical Society
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• v.8 no.1
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• pp.31-39
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• 1987

By using a complete rate constant($k_e$) which treats a solvent (water) as a reactant, and a conventional rate constant($k_c$), which ignores the solvent in describing the rate, the parameters ${\Delta}V^{\neq}_s,\;{\Delta}H^{\neq}_s\;and\;{\Delta}S^{\neq}_s$ were introduced. These quantities represent the volume change, the enthalpy change, and the entropy change accompanying the electrostriction which occurs when solvent molecules condense on the activated complex. The authors measured the rates of the solvolysis of benzoyl chloride in water-acetone mixtures at $15^{\circ}$ to $30^{\circ}C$ and 1 bar to 2500 bars. Applying the authors' theory to the experimental results, the parameters, ${\Delta}V^{\neq}_s,\;{\Delta}H^{\neq}_s\;and\;{\Delta}S^{\neq}_s$ were evaluated, and it was found that they are all negative, indicating that water dipoles condense on the activated complex. They also proposed the following equations: ${\Delta}H^{\neq}_c\;=\;{\Delta}H^{\neq}_e\;+\;{\Delta}H^{\neq}_s\;and\; {\Delta}S^{\neq}_c\;=\;{\Delta}S^{\neq}_e\;+{\Delta}S^{\neq}_s\;,\;where\;{\Delta}H^{\neq}_c\;and\;{\Delta}H^{\neq}_c\;and\;{\Delta}S^{\neq}_s $are the activation enthalpy change and the activation entropy change for the conventional reaction rate, respectively, and ${\Delta}H^{\neq}_e$ and ${\Delta}S^{\neq}_e$ are the corresponding quantities for the complete reaction rate. The authors proposed that for the $SN_1$ type, all the quantities, ${\Delta}V^{\neq}_s,\;{\Delta}S^{\neq}_s\;,{\Delta}H^{\neq}_s\;and\;{\Delta}S^{\neq}_s$ are comparatively large, and for the $SN_2$ type, these quantities are smaller than for the $SN_1$ type, and occasionally the case ${\Delta}S^{\neq}_e$ < 0 occurs. Using these criteria, the authors concluded that at high temperature, high pressure and for a high water content solvent, the SN_1$ type mechanism predominates whereas in the reversed case the $SN_2$M type predominates.

• Journal of the Korean Geographical Society
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• v.31 no.2
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• pp.106-127
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• 1996

In Korea, modern geomorphology has developed as one of main subjects in geography, such as in Europe. Geomorphology is one of the most advanced specialties in the geography dicipline, since foundation of Korean Geographical Society in 1945. Untill 1960's study, first generation of the Korean geomorphologists trained the younger ones, together with energetic research activities. Their great works in education and research established the base of ulterier development of the geomorphology in Korea. Since 1970s, research manpower and quality has incresed rapidly, partly due to the various international activities and cooperations of Korean geomorphologists. Owing to above development, Korean geomorphologist was able to found "The Geomorphological Association of Korea" in 1990 and publish "Journal of GAK", since 1994. Furthermore, geomorphologists are playing important roles in interdisciplinary academic societies, such as "The Korean Quaternary Assocition". Still 1960s, our research had focused on the identification and interpretation of erosional surfaces in Korea Peninsular. Of course, W.M. Davis's "Geographical Cycle Theory" and L.C. King's "Pedimentation Theory" had a great influence on the Koerans' works. After 1970s, the study of erosional surface played the important role in setting up the morphoclimatic viewpoint and methodology. Research scope tend to be notably broad and various than it was untill 1960's. Disposotion of the scientific methods and techniques become more and more apparent. These trends of research has settled precise descreption and interpretation of actual landforms, based on the careful field works, scientific measuring, and analisis, rather than methodology focused on the particular master theories. Recent geomorphological researches show the scope from climatic geomorphology and Quaternary geomorphology to granite and limestone weathering, pedo-geomorphogenic environment and periglacial landforms, focused on the small-to-medium scales. And then there have been new trying to interprete erosional surfaces such as hillslopes and terraces. Also, studies of coastal and plain landforms have been successfully developed. Recent new trends show the quantitative and analytic modelling using field measurement and laboratory work, and study on the human impacts on the natural landforms.y on the human impacts on the natural landforms.

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.5
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• pp.289-310
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• 2002

Die Arbeit versucht, den Textbegriff aus prototypentheoretischer Sicht neu zu orientieren. Damit wird unter Text immer eine monologisch geschriebene sprachliche $\"{A}u{\ss}erung$ aus mehreren $S\"{a}tzen$ verstanden. Die in de Beaugrande/Dressler(l98l) als wichtig bezeichnete Textmerkmale wird dann in Bezug auf Vater(1992), $L\"{o}tscher(1987)$ und Klein/von Stutterheim (1991) kritisch $gekl\"{a}rt$. Daraus ergibt sich eine merkmalsorientierte Textbestimmung: Ein Text ist eine abgeschlossene themenorientierte kommunikative Einheit in einem konkreten Kontext; er hat eine bestimmte kommunikative Funktion und $erf\"{u}llt\;koh\"{a}rente$ Bedingungen. Meine These ist: Typische Texte sind auf Mustern, $n\"{a}mlich$ auf Prototypen bezogen. Textmuster sind als Prototypen bezeichnet, die in unterschiedlichem $Ma\ss\;Spielraum\;f\"{u}r\;Variationen\;und\;Kreativit\"{a}t$ lassen. Textmuster sind zu beschreiben $\"{u}ber$ das Zusammenspiel von nichtsprachlichem Handlungstyp und sprachlicher Textsorte. Dieses Zusammenspiel yon Handlungsaspekten wird in prototypischer Weise mit bestimmten Textmerkmalen verbalisiert. Mit Textmusterbeschreibungen werden jeweils prototypische Exemplare beschrieben: die beste Exemplare, die klar als solehe erkennbar sind. Die Formulierung 'Es war einmal....'. ist $f\"{u}r\M\"{a}rchen$ zwar prototypische Anfangsform, aber sie wird nur in etwa einem drittel der $F\"{a}lle$ verwendet. Prototypische Textmustermerkmale sind also nicht obligatorisch. Das $hei{\ss}t$, dass die Realiseirungen je nach individueller bzw. kultureller Situation und damit verfolgtem Zweck variabel sind Damit habe ich mich am Beispiel der Textsorte $besch\"{a}ftigt$.

• Journal of Korean Society of Forest Science
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• v.97 no.3
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• pp.326-331
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• 2008

This study was carried out to analyze the characteristics of each factors by using the quantification theory(I) for prediction of landslide hazard area. The results obtained from this study were summarized as follows; The stepwise regression analysis between landslide sediment ($m^3$ ) and environmental factors, factors affecting landslide sediment ($m^3$ ) were high in order of mixed (forest type), < 15 cm(soil depth), 801~1,200 m (altitude), $31{\sim}40^{\circ}$ (slope gradient), 46 cm < (soil depth), 1,201 m < (altitude) and s(aspect). According to the range, it was shown in order of soil depth (0.3784), altitude (0.2876), forest type (0.2409), slope gradient (0.1728) and aspect (0.1681). The prediction of landslide hazard area was estimated by score table of each category. The extent of prediction score was 0 to 1.2478, and middle score was 0.6239. Class I was over 1.1720, class II was 0.7543 to 0.1719, class III was 0.4989 to 0.7542 and class IV was below 0.4988.

• The Journal of the Korea Contents Association
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• v.10 no.10
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• pp.161-171
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• 2010

Peter Brook has been often referred to as the most important contemporary theater director in the West. The fact that he has directed many plays without being tied to a single theatrical theory occasionally makes people think he is a eclectic imitator. But when you carefully observe his work, you can understand that his openness is nothing else but the pursuit and examination of theatrical communication. In this context, Brook's idea reminds us of Bricolage. Bricolage has been widely known after the publication of "The Savage Minds". L$\acute{e}$vy-Strauss used the word to describe characteristic patterns of mythological thought in compared with modern scientific thought and regarded it as a system of thought that we need to restore. Director Peter Brook have sought effective ways to fill the empty space with his broad view of theatre and life. His consistent attempt reveals positive theatrical idea with the expansive possibilities of Bricolage thought.

• Journal of Korean Public Health Nursing
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• v.4 no.1
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• pp.17-23
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• 1990

The purpose of this study were l) to provide information useful in developing an individualized health promotion program, 2) to test the correlations among the level of locus of control, health promotion activities and value placed on self. 3) to assess the factors of health promotion activities and value placed on self. The level of locus of control was measured by Walston/Walston's scales. The levels of health promotion activities and value placed on self were measured by Pender/Pender's scales. The sample consist of 122 female students in a University in Seoul. Their mean ages were 21. The results are summarized as follows; 1. Hypothesis 1 : The higher the score of internal health locus of control, the higher the score of health promotion activities was supported. 2. Hypothesis 2 : The higher the score of value placed on self, the higher the score of health promotion activites was supported. 3. Hypothesis 3 : The higher the score of value placed on self, the higher the score of internal health locus of control was supported. 4. The highest score of the factors of health promotion activities is nutritional practice$(14.976\pm.907)$ and the lowest score is self care$(1l.930\pm1.169).$ In conclusion, several implications for nursing emerge from the theory and research behind the locus of control concept. First, scales to measure locus of control may be useful in evaluating health education programs. Second, it may be adventageous to screen individuals using a health locus of control scale before placement into a treatment program that matches their needs. Third, health professionals may want to train individuals to become more internals appear more likely to engage in positive health behaviors.

• Textile Coloration and Finishing
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• v.6 no.1
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• pp.33-43
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• 1994

In the present work, to clarify the mechanism of the neutral salt effect on the alkaline hydrolysis of PET, many salts with different cations like LiCl, NaCl, KCl, CsCl were added to the aqueous alkaline solutions. Then PET was hydrolyzed with aqueous solutions of many salts in alkali metal hydroxides under various conditions. Some conclusions obtained from the experimental results were summarized as follows. The reaction rate of the alkaline hydrolysis of PET was increased by the addition of neutral salts and In k was increased nearly linearly with the square root of ionic strength of reaction medium. This fact suggested that the ionic strength effect by Debye-Huckel and Bronsted theory was exerted on the reaction. The specific salt effect was also observed. The reaction rate was increased with the increase in the electrophilicity of cations of neutral salts, i. e., in the order of $Cs^+$/ < $K^+$/ $a^+$/ $i^$^+$. It was considered that the reaction rate was increased in the order of C $s^+$. < $K^+$. $a^+$. $i^+$. because the lowering effect of the cations on the negative charge of PET surface was increased with the electrophilicity of cations. It was thought that $E_{a}$ was increased because the cations of neutral salts decreased the negative charge of PET surface. It, however, was inferred from the increase in ${\Delta}$S＊ and the decrease in the ${\Delta}$G＊ that the cations of neutral salts associated with PET increased the collision frequency between carbonyl carbon and OH- ion and then accelerated the reaction rate.te.