• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.7
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• pp.723-730
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• 2012

During the cold wire-drawing process, the diameter of a wire is reduced and the length of the wire is increased as the wire passes through the die. The pressure and sliding motion at the interface between the wire and die cause elastic recovery of the workpiece and friction and wear on the die. In addition, wire deformation and frictional heating raise the temperature of the wire and die, resulting in difficulty in manufacturing the drawn products according to a designated inner diameter of the die, deviating from the designated dimension or the inner diameter of the die. In this study, considering the die temperature distribution, the effects of dimensional changes of the drawn products were analyzed quantitatively; these changes are caused by the elastic deformation of the die, the elastic recovery of the workpiece, and the thermal deformation of both the die and the workpiece. It was confirmed that the elastic recovery of the workpiece influenced these changes the most. The initial dies considering these factors could avoid deviation from the designated dimension, and the desired drawn products were obtained by using the designed initial drawing dies.

• Journal of the Korea Institute of Building Construction
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• v.3 no.3
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• pp.113-120
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• 2003

The purpose of this thesis is to provide an appropriate trade-off information for the conflicting interests caused by the various factors between building owner and contractor during selecting the contractor and performing the construction work, in which the construction was contracted by open bidding from the government or private organizations. In order to propose the legitimate evidence, the differences between the domestic contract sheet of drawing change and the process of drawing change and those of the foreign countries were compared and analysed. The number of construction ordered in Youngdong area in 2001 whose construction expenses are more than 100,000,000 won is 218 items and 147,005,000,000 won in total cost. Among them, the number of 218 items whose total cost amounts to 16,705,000,000 (11.36%) is in case of increase of construction expenses due to the drawing changes, and the number of 48 items whose total cost amounts to 2,009,000,000 won (1.37%) is the case of decrease. In conclusions, the contractor could have more benefits than the building owner in case they submit the detailed estimate sheet without eliminating the increasing expenses of construction. It is shown that the building owner's loss is increasing whenever the labor cost is higher than material cost. Therefore, this thesis proposes a proper standards for the harmonious compromise between the contractor and the building owner for the problems caused by the drawing changes when the contract agreement is occurred.

• Journal of computational fluids engineering
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• v.16 no.1
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• pp.22-29
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• 2011

In this study, the glass fiber drawing from a silica preform in the furnace for the optical fiber manufacturing process is numerically simulated by considering the radiative heating of cylindrically shaped preform. The one-dimensional governing equations of the mass, momentum, and energy conservation for the heated and softened preform are solved as a set of the boundary value problems along with the radiative transfer approximation between the muffle tube and the deformed preform shape, while the furnace heating is modeled by prescribing the temperature distribution of muffle tube. The temperature-dependent viscosity of silica plays an important role in formation of preform neck-down profile when the glass fiber is drawn at high speed. The calculated neck-down profile of preform and the draw tension are found to be reasonable and comparable to the actual results observed in the optical fiber industry. This paper also presents the effects of key operating parameters such as the muffle tube temperature distribution and the fiber drawing speed on the preform neck-down profile and the draw tension. Draw tension varies drastically even with the small change of furnace heating conditions such as maximum heating temperature and heating width, and the fine adjustment of furnace heating is required in order to maintain the appropriate draw tension of 100~200 g.

• Textile Coloration and Finishing
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• v.22 no.3
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• pp.272-281
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• 2010

This paper surveys the effects of drawing conditions of the worsted staple yarns on the mechanical properties of the knitted fabrics for highly aesthetical fabrics. The drawn worsted yarns were made on the yarn drawing system with various draw ratios under the fixed conditions of setting time, reduction and oxidation. The knitted fabric specimens were prepared on the 16 gauge circular knitting machine using these drawn worsted staple yarns. The tensile, shear, bending, compression and surface properties of these knitted fabrics were measured by KES-FB-AUTO-A system and also discussed with the drawing conditions. The tensile linearity, shear stiffness and bending rigidity decreased with increasing draw ratio. Any changes were not shown on the compressional properties with drawing conditions. But the friction coefficient of the knitted fabric on the course direction increased with increasing draw ratio, while there was no change according to the draw ratio on the wale direction.

• Transactions of Materials Processing
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• v.17 no.3
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• pp.170-181
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• 2008

The shape of rectangular cup used for Ni-MH(Nickel-coated Metal Hydrogen) battery for hybrid car looks quite simple, but the forming process of extruding and setting up process design are highly difficult. Furthermore, there are few concrete reports on the rectangular deep drawn cup as part of hybrid vehicles till now. In this study, process design for rectangular cup in the multi-stage deep drawing process is carried out, and FE analysis is also preformed based on the result of the process design. From the simulation result, some unexpected problems such as earing, wrinkling and excessive thickness changes of the intermediate blank occurred. To overcome these failures, a series of modification for punch shape in the forming process design are completed and applied. Considering the modified punch shape in the multi-stage deep drawing process, additional FE analysis is also carried out and the simulation result is verified in view of the deformed shape, thickness change and effective strain distribution. The result of FE analysis with the improved process design confirmed not only reducing thinning of wall and possibilities of failure but also improving the quality of drawing product through the modification of punch shape.

• Journal of Oriental Neuropsychiatry
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• v.18 no.1
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• pp.185-196
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• 2007

Objective : This experimental Study was designed to investigate the effects of FOENICULI FRUCTUS(FF) on the change of inhibition lactate dehydrogenase(LDH) activity in neuronal cells and cytokines production in serum of cerebral ischemic rats. Method : FOENICULI FRUCTUS(FF)freeze dry powder and FF on the LDH activity in neuronal cells. Changes of FF on the physiological parameters(PaO2, PaCO2, MABP and HR) in crerbral ischemic rats. Effects of FF on the IL-1beta production, $TNF-{\alpha}$ production, $TGF-{\beta}$ production, and IL-10 in serum of cerebral ischemic rats. MCAO :. cytokines production of serum by drawing from femoral arterial blood after MCAO 1 hr. Reperfusion : cytokines production of serum by drawing from femoral arterial blood after reperfusion 1 hr. Results and Conclusion : 1. FF did not inhibit lactate dehydrogenase(LDH) activity in neuronal cells. 2. In serum by drawing from femoral arterial blood after middle cerebral arterial occlusion(MCAO) 1 hr and reperfusion 1 hr, sample group was significantly decreased $IL-l{\beta}$ production compared with control group 3. In serum by drawing from femoral arterial blood after MCAO 1 hr and reperfusion 1 hr, sample group was significantly decreased $TNF-{\alpha}$ production compared with control group. 4. In serum by drawing from femoral arterial blood after MCAO 1 hr and reperfusion 1 hr, sample group was significantly increased $TGF-{\beta}$ production compared with control group. 5. In serum by drawing from femoral arterial blood after reperfusion 1 hr, sample group was significantly increased IL-10 production compared with control group. This results were suggested that FF had inhibitive effect on the brain damage by inhibited LDH activity, $IL-l{\beta}$ and $TNF-{\alpha}$production, but accelerated $TGF-{\beta}$ production and IL-10 production.

• Journal of the Korean Society of Earth Science Education
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• v.7 no.2
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• pp.151-158
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• 2014

This study was designed to analyze fifty-seven high school students' perception of environmental change through drawing. More than half of the students showed the present environment as a pure natural space, and they represented the future environment as a space which includes the artificial contents, they also expressed technology advance in their picture. Most of high school students showed the negative perception to express the present environmental condition in a polluted space by human. In matters of the future environmental condition, half of students expressed it positively, the other half of students expressed it negatively, we should develop our will to improve the environment, and try to change student's preception positively.

• Korean Journal of English Language and Linguistics
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• v.4 no.2
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• pp.151-174
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• 2004

A historical investigation reveals that English preposition with underwent a change from OPPOSITION to ASSOCIATION and further to ACCOMPANIMENT, where the first stage shows peculiarity in that the two concepts involved comprise an unusual set to form an extensional chain. Intrigued by this oddity, this paper aims to investigate the semantic structure of English preposition with from a grammaticalization perspective. We review mechanisms and models of semantic change and evaluate their adequacy with the semantic structure and change shown by with. Drawing upon the observed fact that with underwent the apparent antonymic semantic change, it is argued that such semantic change mechanisms as metaphor, metonymy, subjectification, and generalization have difficulties explaining the change, and that only the Frame-of-Focus Variation can effectively account for this peculiar change type. In terms of semantic change models, we argue that the Bleaching Model cannot effectively provide an explanation; that the Loss and Gain Model has problems in explaining the motivation of change directions; that the Metonymic-Metaphoric Model cannot be assessed at the current level of investigation; and that the Overlap Model and the Prototype Extension Model excellently account for the macro-level changes.

• Journal of the Korean Society of Earth Science Education
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• v.3 no.2
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• pp.99-108
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• 2010

This study lays its purpose on examining the effects of lessons with the application of drawing tasks on changes in conception among gifted science students. The lesson with the application of drawing tasks means the lesson where students express key concepts regarding lesson subjects in drawings which are then applied to the lessons to develop conception among the learners. This study analyzed the effectiveness of lessons by comparing conception scores before and after experiments between an experiment group with the application of drawing tasks and a control group with normal lessons for the gifted in general for 8 months from March to October, 2008. In addition, the researcher examined how the effectiveness of the developed lessons show differently according to levels of meta-cognition, creative problem-solving abilities, and scientific inquiry skills among the gifted students. The results from this study are as the following. First, lessons with the application of drawing tasks were effective in changing conception among the gifted science students. It is possibly because in the process where one student compare his/her own drawings with the others' ones and discuss them, changes in conception occurred effectively among the learners. Second, it was revealed that lessons utilizing drawing tasks have equal effects on changes in conception among both student groups irrespective of their levels of meta-cognition. Accordingly the lesson for changing perceptions utilizing drawing tasks developed in this study is a program which can be applied to all gifted science students in order to change conception among them. Third, lessons utilizing drawing tasks have the greatest effects on the gifted science students at a 'middle' level of creative problem solving abilities. Fourth, lessons utilizing drawing tasks have the greatest effects on the gifted science students at a 'middle' level of scientific inquiry skills. Putting these results together, it is thought that if lessons utilizing drawing tasks are applied to gifted science students, not only their concepts would be changed effectively but also their attitudes toward science would be changed positively.

• Journal of Information Technology Applications and Management
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• v.30 no.5
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• pp.59-82
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• 2023

The present research aims to examine whether learning from the supervisor influences readiness for change with the mediating impact of planfulness. Drawing upon the theory of planned behavior, it is hypothesized that learning from the supervisor positively impacts planfulness ability in individuals, which in turn enhances the readiness for change. Through using convenience sampling, the sample of 451 was collected from employees working full-time in the manufacturing and I.T. service organizations in India. Structural equation modeling and regression analysis indicate that learning from the supervisor is positively associated with readiness for change and planfulness. Additionally, planfulness fully mediated the relationship between learning from the supervisor and readiness to change. The findings of the present research highlight that continuous support and learning from the supervisor enhances the planfulness ability of the individual and consequently enhances individual readiness for change. The current research is pioneering in testing the hypothetical model associating learning from the supervisor, planfulness, and readiness for change.