• Journal of the Korean Society of Costume
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• v.58 no.8
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• pp.63-73
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• 2008

From the ancient Korea to the late Joseon Korean fur and leather had been preferred in and out of Korea for their good quality and excellent manufacturing skill. Since Unified Silla (A.D.676${\sim}$A.D.936) Korean fur and leather were manufactured divisionally by workmen specialized in materials and products, and such manufacturing process was succeeded to Goryeo and Joseon. Manufacturing of fur and leather was consisted of as follows: hunting and butchering - peeling - beating with a paddle and removing fat - oil manufacturing - drying - tanning, then cutting and sewing, and there was a special caring method. In order to make good fur and leather, each process of manufacturing needed particular techniques and all available methods were tried to have tender fur and leather by using smoking, excrement, lime, vegetable tannin and even cerebral liquid. And also required mouth-chewing and hand-pounding with a lot of time and of labor Keeping furs resilience and flexibility, sowing several skins together, even when the after-all-process skin was converted into clothes, was much more difficult than sewing fabric. Thus, the manufacturing cost was as much expensive as skin materials, and the volume of manufacturing of fur and leather was also limited. Therefore, fur and leather must have been popular for scarcity value in the manufacturing process, and this scarcity must have caused an extreme luxury of fur.

• Earthquakes and Structures
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• v.15 no.5
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• pp.555-564
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• 2018

Allowing structures to uplift in earthquakes can significantly reduce or even avoid the development of plastic hinges within the structure. The permanent deformations in the structure can thus be minimized. However, uplift of footings can cause additional horizontal movements of a structure. With an increase in movement relative to adjacent structures, the probability of pounding between structures increases. This experimental study reveals that the footing mass can be used to control the vertical displacement of footing and thus reduce the horizontal displacements of an upliftable structure. A four storey model structure with plastic hinges and uplift capability was considered. Shake table tests using ten different earthquake records were conducted. Three different footing masses were considered. It is found that the amplitude of footing uplift can be greatly reduced by increasing the mass of the footing. As a result, allowing structural uplift does not necessary increase the horizontal displacement of the structure. The results show that with increasing footing weight, the interaction between structural and footing response can increase the contribution of the higher modes to the structural response. Consequently, the induced vibrations on secondary structure increase.

• Research in Community and Public Health Nursing
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• v.12 no.2
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• pp.482-490
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• 2001

Purpose I investigated how beliefs in punishment have influence on child abuse. Also, I investigated how socio-demographic variables of parents' have influences on child abuse by parents. Sampling was conveniently and total 160 parents replied to the study. Data analysis was done by descriptive statistics, Pearson's correlation using SPSSWIN. The results were as follows. Mild child abuse: 'Throwing the object at me(21.1%)', 'Clutching, and pushing (21.0%)', 'Slapping on the cheek (19.1 %), Severe child abuse: 'Kicking, pounding and biting(4.1%)', 'Rod, stick, belt, broom beating using a various objects such as(51.7%)', 'Beating all over the body(6.8%)'. Very severe child abuse: 'Burning with cigarette (0%)', 'Threatening me with a knife, a hammer, a naxe, a gimlet the objects such as(0.7%)', 'Injuring me with the objects such as (0%)', 'Hospitalized by belting(0%)'. Correlations of major variables were as follows. Physical child abuse by elementary student's parents has significantly positive correlation with beliefs in punishment(r= .244 p= .003) and has significantly negative correlation with parent's age(r=-.273, p=.001). But physical child abuse has not significant correlations with family income, education. Conclusion: Beliefs in punishment of parents have influences on child abuse. To prevent child abuse, effective parenting program development is required.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.27-36
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• 1990

Injeolmi is a kind of rice cake made from glutionusrice grains by steaming and pounding much into dough. The way of making Injeolmis has an important effect on the characteristics of Injeolmis; whether the glutinous rice is Japonica or Japonica/Indica, and whether it is steamed in rice grain, or in rice powder. The characteristics of Injeolmi were investigated through sensory evaluation and Instron Universal testing machine. The results were as follows; 1. Injeolmi which was steamed in glutinous rice was more chewier than powder Injeolmi after 48 hours. 2. In the case of changing ${\beta}$-starch to ${\alpha}$-starch by reheating. Injeolmi with microwave oven, the result was same as above investigation in color, appearance, and chewiness. But in hardness grain Injeolmi became tenderer. 3. Instron measurement of texture indicated that there were significant differences in hardness. This result was the same as that by the sensory evaluation. 4. The preference for Injeolmi was increased when it was made of high moisture contented glutinous rice. japonica had more moisture than J/Indica.

• Structural Engineering and Mechanics
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• v.58 no.6
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• pp.1127-1143
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• 2016

The pounding phenomenon in adjacent structures happens in severing earthquakes that can cause great damages. Connecting neighboring structures with active and semi-active control devices is an effective method to avoid mutual colliding between neighboring buildings. One of the most important issues in control systems is applying online control force. There will be a time delay if the prose of producing control force does not perform on time. This paper proposed a time-delay compensation method in coupled structures control, with semi-active Magnetorheological (MR) damper. This method based on Newmark's integration is adopted to mitigate the time-delay effect. In this study, Lyapunov's direct approach is employed to compute demanded voltage for MR dampers. Using Lyapunov's direct algorithm guarantees the system stability to design a controller based on feedback. Because of the strong nonlinearity of MR dampers, the equation of motion of coupled structures becomes an involved equation, and it is impossible to solve it with the common time step methods. In present paper modified Newmark-Beta integration based on the instantaneous optimal control algorithm, used to solve the involved equation. In this method, the response of a coupled system estimated base on optimal control force. Two MDOF structures with different degrees of freedom are finally considered as a numeric example. The numerical results show, the Newmark compensation is an efficient method to decrease the negative effect of time delay in coupled systems; furthermore, instantaneous optimal control algorithm can estimate the response of structures suitable.

• Korean Journal of Applied Biomechanics
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• v.21 no.1
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• pp.9-16
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• 2011

The purpose of this study is to analyze the effects of both various shoe types and bare feet on ground reaction force while walking. Ten first-year female university students were selected. A force platform(Kistler, Germany) was used to measure ground reaction force. Six types of shoe were tested: flip flops, canvas shoes, running shoes, elevated forefoot walking shoes, elevated midfoot walking shoes, and five-toed shoes. The control group was barefooted. Only vertical passive/active ground reaction force variables were analyzed. The statistical analysis was carried out using the SAS 9.1.2 package, specifically ANOVA, and Tukey for the post hoc. The five-toed shoe had the highest maximum passive force value; while the running shoe had the lowest. The first active loading rate for running shoes was the highest; meanwhile, bare feet, the five-toed shoe, and the elevated fore foot walking shoe was the lowest. Although barefoot movement or movement in five toed shoes increases impact, it also allows for full movement of the foot. This in turn allows the foot arch to work properly, fully flexing along three arches(transverse, lateral, medial), facilitating braking force and initiating forward movement as the tendons, ligaments, and muscles of the arch flex back into shape. In contrast movement in padded shoes have a tendency to pound their feet into the ground. This pounding action can result in greater foot instability, which would account for the higher loading rates for the first active peak for padded shoes.

• Journal of Environmental Science International
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• v.9 no.1
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• pp.81-88
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• 2000

Every year, 1.1 million tons of rice-hull are produced in South Korea by the by-product in pounding rice. But they has mainly been utilized as a fuel, agricultural compost and moisture proofs. So, it's very valuable to use waste rice-hull for activated carbon manufacture. SiO2 content was the highest among inorganics in rice-hull. Therefore, the SiO2 extraction experiments were carried out under the various conditions of pH 9 to 14, reaction time from 2 to 24 hrs and various temperature of 20 to 100℃. The results showed that increase in pH and temperature enhanced SiO2 extraction from the carbonized rice-hull. The surface area of the carbonized rice-hull indicating activated carbon adsorption capacity was very small as 178∼191 m2/g at first. However, it was increased to 610∼675 m2/g when extracted in alkali solution at 100℃. When the mixing rate of carbonized rice-hull and NaOH was 1:1.5, iodine No. and surface area of activated rice-hull during 10 min at 700℃ were 1,650 mg/g and 1837 m2/g, respectively. Subsequently, an activated carbon with specific surface area of 1,300∼1,900m2/g was manufactured in a short contact time of 10∼30 min with a mixing rate of 1:1.5 in carbonized rice-hull and NaOH, and iodine No. and specific surface area increased as the amount of SiO2 removal increased.

• Earthquakes and Structures
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• v.10 no.6
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• pp.1451-1465
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• 2016

The effectiveness of base isolation (BI) systems for mitigation of seismic vibration of bridges have been extensively studied in the past. It is well established in those studies that the performance of BI system is largely dependent on the characteristics of isolator yield strength. For optimum design of such systems, normally a standard nonlinear optimization problem is formulated to minimize the maximum response of the structure, referred as Stochastic Structural Optimization (SSO). The SSO of BI system is usually performed with reference to a problem of unconstrained optimization without imposing any restriction on the maximum isolator displacement. In this regard it is important to note that the isolator displacement should not be arbitrarily large to fulfil the serviceability requirements and to avoid the possibility of pounding to the adjacent units. The present study is intended to incorporate the effect of excessive isolator displacement in optimizing BI system to control seismic vibration effect of bridges. In doing so, the necessary stochastic response of the isolated bridge needs to be optimized is obtained in the framework of statistical linearization of the related nonlinear random vibration problem. A simply supported bridge is taken up to elucidate the effect of constraint condition on optimum design and overall performance of the isolated bridge compared to that of obtained by the conventional unconstrained optimization approach.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.10a
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• pp.291-300
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• 1999

An idealized analytical model is proposed to estimate the effects of restrainer upon global response behaviors of a bridge system under seismic excitations. Pounding actions between adjacent vibration units and friction at movable supports are introduced in addition to other phenomena such as nonlinear behaviors of pier, motions of the foundation and abutment to achieve the better prediction of the bridge motion. The applied restrainer is assumed to be a dead-band system, which has the force clearance and the linear-elastic force. Using the proposed model, the dynamic characteristics of a bridge system retrofitted by restrainers is examined, and the effects of stiffness and clearance length of restrainer is also investigated. The main effect of the application of restrainers is found to reduce the relative displacements and the trend becomes greater with the shorter clearance length except between pier units. It is found that the relative displacements between abutment and adjacent pier units are decreased as the stiffness of restrainer increases, but almost independent upon the stiffness increments of restrainer. However, the relative displacements between pier units tend to be increased due to the applications of the restrainers.

• Coupled systems mechanics
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• v.9 no.2
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• pp.183-200
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• 2020

Connection of adjacent buildings with stiff links is an efficient approach for seismic pounding mitigation. However, use of highly rigid links might alter the torsional response in asymmetric plans and although this was mentioned in the literature, no quantitative study has been done before to investigate the condition numerically. In this paper, the effect of rigid coupling on the elastic lateral-torsional response of two adjacent one-story column-type buildings has been studied by comparison to uncoupled structures. Three cases are considered, including two similar asymmetric structures, two adjacent asymmetric structures with different dynamic properties and a symmetric system adjacent to an adjacent asymmetric one. After an acceptable validation against the actual earthquake, the traditional random vibration method has been utilized for dynamic analysis under Ideal white noise input. Results demonstrate that rigid coupling may increase or decrease the rotational response, depending on eccentricities, torsional-to-lateral stiffness ratios and relative uncoupled lateral stiffness of adjacent buildings. Results are also discussed for the case of using identical cross section for all columns supporting eachplan. In contrast to symmetric systems, base shear increase in the stiffer building may be avoided when the buildings lateral stiffness ratio is less than 2. However, the eccentricity increases the rotation of the plans for high rotational stiffness of the buildings.