• 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.

• Journal of Korean Association for Spatial Structures
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• v.11 no.1
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• pp.121-130
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• 2011

Space frame structures have the advantage of constructing a large space structures without column and it may be considered as a shell structure. Nevertheless, with the characteristics of thin and long term of spacing, the unstable problem of space structure could not be set up clearly, and there is a huge difference between theory and experiment. Therefore, in this work, the tangential stiffness matrix of space frame structures is studied to solve the instability problem, and the nonlinear incremental analysis of the structures considering rise-span ratio(${\mu}$) and the ratio of load($R_L$) is performed for searching unstable points. Basing on the results of the example, global buckling can be happened by low rise-span ratio(${\mu}$), nodal buckling can be occurred by high rise-span ratio(${\mu}$). And in case of multi node space structure applying the ratio of load($R_L$), the nodal buckling phenomenon occur at low the ratio of load($R_L$), the global buckling occur a1 high the ratio of load($R_L$). In case of the global buckling, the load of bifurcation is about from 50% to 70% of perfect one's snap-through load.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.4
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• pp.285-291
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• 2004

A simulated moving bed (SMB) chromatography system is a powerful tool for preparative scale separation, which can be applied to the separation of chiral compound. We have de-signed our own lab-scale SMB chromatography using 5 HPLC pumps, 6 stainless steel columns and 4 multi-position valves, to separate a racemic mixture of ketoprofen in to its enantiomers. Our design has the characteristics of the low cost for assembly for the SMB chromatography and easy repair of the unit, which differs from the designs suggested by other investigators. It is possible for the flow path through each column to be independently changed by computer control, using 4 multi-position rotary valves and 5 HPLC solvent delivery pumps. In order to prove the operability of our SMB system, attempts were made to separate the (S)-ketoprofen enantiomer from a ketoprofen racemic mixture. The operating parameters of the SMB chromatography were calculated for ketoprofen separation from a batch chromatography experiment as well as by the triangle theory. With a feed concentration of 1 mg/mL, (S)-ketoprofen was obtained with a purity of 96% under the calculated operating conditions.

• Structural Engineering and Mechanics
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• v.75 no.5
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• pp.633-642
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• 2020

Artificial neural networks (ANNs) are known as intelligent methods for modeling the behavior of physical phenomena because of it is a soft computing technique and takes data samples rather than entire data sets to arrive at solutions, which saves both time and money. ANN is successfully used in the civil engineering applications which are suitable examining the complicated relations between variables. Functionally graded materials (FGMs) are advanced composites that successfully used in various engineering design. The FGMs are nonhomogeneous materials and made of two different type of materials. In the present study, the bending analysis of functionally graded material (FGM) beams presents on theoretical based on combination of mixed-finite element method, Gâteaux differential and Timoshenko beam theory. The main idea in this study is to build a model using ANN with four parameters that are: Young's modulus ratio (E_t/E_b), a shear correction factor (k_s), power-law exponent (n) and length to thickness ratio (L/h). The output data is the maximum displacement (w). In the experiments: 252 different data are used. The proposed ANN model is evaluated by the correlation of the coefficient (R), MAE and MSE statistical methods. The ANN model is very good and the maximum displacement can be predicted in ANN without attempting any experiments.