• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.693-697
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• 2009

Physically-based WEPP watershed version was applied to a watershed, located at Jawoon-ri, Gangwon with very detailed rainfall data, rather than daily rainfall data. Then it was validated with measured sediment data collected at the sediment settling ponds and through overland flow. The $R^2$ and the EI for runoff comparisons were 0.88 and 0.91, respectively. For sediment comparisons, the $R^2$ and the EI values were 0.95 and 0.91. Since the WEPP provides higher accuracies in predicting runoff and sediment yield from the study watershed, various slope scenarios (2%, 3%, 5.5%, 8%, 10%, 13%, 15%, 18%, 20%, 23%, 25%, 28%, 30%) were made and simulated sediment yield values were analyzed to develop appropriate soil erosion management practices. It was found that soil erosion increase linearly with increase in slope of the field in the watershed. However, the soil erosion increases dramatically with the slope of 20% or higher. Therefore special care should be taken for the agricultural field with higher slope of 20% or higher. As shown in this study, the WEPP watershed version is suitable model to predict soil erosion where torrential rainfall events are causing significant amount of soil loss from the field and it can also be used to develop site-specific best management practices.

• Journal of Electrical Engineering and Technology
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• v.3 no.1
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• pp.88-93
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• 2008

The electromagnetic parameters of a permanent magnet synchronous motor (PMSM) such as the open load permanent magnet flux, d axis reactance $X_d$, and q axis reactance $X_q$, are most essential to the performance analysis and optimization design of the motor. Based on the numerical analysis of the 3D electromagnetic field, the three electromagnetic parameters of permanent magnet synchronous motors with U form interior rotor structures are calculated by FEA. The rules of the leakage coefficient and reactance parameters changing with the air gap length, permanent magnet magnetism length, and isolation magnetic bridge dimensions in the rotor are given. The calculated values agree well with the measured values. The FEA results are integrated with the self compiled electromagnetic design program to optimize the prototype motor. The tested performances of the prototype motor prove that the method is suitable for the optimization of motor structure.

• Journal of the Korean Operations Research and Management Science Society
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• v.38 no.1
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• pp.139-152
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• 2013

The purpose of this study is to claim the validity of tuning the architecture of neural network models for multi-class classification. A neural network model for multi-class classification is basically constructed by building a series of neural network models for binary classification. Building a neural network model, we are required to set the values of parameters such as number of hidden nodes and weight decay parameter in advance, which draws special attention as the performance of the model can be quite different by the values of the parameters. For better performance of the model, it is absolutely necessary to have a prior process of tuning the parameters every time the neural network model is built. Nonetheless, previous studies have not mentioned the necessity of the tuning process or proved its validity. In this study, we claim that we should tune the parameters every time we build the neural network model for multi-class classification. Through empirical analysis using wine data, we show that the performance of the model with the tuned parameters is superior to those of untuned models.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.1
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• pp.64-69
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• 2000

This paper investigates the equeeze film damping of a perforated planar micromechanical structure that oscillates in the normal direction to the substrate. Special focus has been places on the effect of holes and edges of the perforated planar microstructures on the squeeze film damping of oscillatory motions. Theoretical models and test structures of the squeeze film damping have been developed for the transversely oscillating perforated plates. A set of nine different test structures, having three different sized with three different numbers of perforations, has been fabricated and tested. The experimental Q-factors, measured from the fabricated test structures, are compared with the theoretical values, estimated from finite element analysis. It is found that the finite element analysis overestimates the Q-factors up to 150% of the experimental values. Major discrepancy comes from the inaccuracy of the zero pressure condition, placed by the finite element analysis along the perforated edges.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.6
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• pp.709-715
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• 2007

The dewaterability of a sludge can be characterized by two ways: the residual moisture content in the sludge cake after dewatering process, and the filtration of the sludge. Time to filter (TTF) represents filtration processes that are special cases of the flow through a solid matrix concept. TTF characterizes a resistance to filtration. The sludge resistance, in turn, can be subdivided into resistances associated with the solid phase and the liquid phase to evaluate the effect of each of the two phases on sludge dewaterability. In order to determine the dewatering characteristics of the water sludge samples, TTF and zeta potential were measured. For these studies cationic polymer was chosen for water sludge dewatering experiments. The zeta potential of thickener sludges neared from minus values to zero values till 4 days after sampling. The dewaterability of thickener sludges using cationic polymer was deteriorated according to the increase of detention time. As the detention time was increased from 4 to 10 days, the optimal dose of the polymer was increased from 4 to 8mg/L. Therefore, the optimal detention time plays an important part for the dewaterability of a sludge.

• Fashion & Textile Research Journal
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• v.13 no.5
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• pp.679-685
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• 2011

The purpose of this study is to analyze the formative characteristics and the aesthetic values of the Power suit in 1980s and the images of the Power suit styles shown in 08/09 F/W, 09 S/S, 09/10 F/W and 10 S/S collections. The results of this study are as follows: 1) The aesthetic values of the Power suit in 1980s are authority, sexuality and luxury to express the power, body and wealth. Authority is represented in wide and hard shoulders with pads and dark colors with stripe and no patterns. Sexuality is represented in tight waist jacket and tight skirt. Luxury is represented in luxurious fabrics and handicraft ornaments. 2) The Power suit styles shown in collections are expressed in classic, romantic, avant-garde and ethnic images: Classic images appeared in jacket which exaggerated shoulders with pads, mini skirt, tapered pants, dark colors with stripe and check patterns, rough materials and a waist belt. Romantic images are represented in the skirt with an asymmetric hem, pastel and splendid colors, lace and silk, romantic details made with gathers and flounces and fantastic accessories. Avant-garde images appeared in the deformed jacket, unperfected skirt, special materials and exaggerated accessories. Ethnic images are represented in big silhouette forms with wide shoulders jacket and wide pants, ethnic patterns, gold, orange and other vivid colors and ethnic accessories.

• Ocean and Polar Research
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• v.37 no.4
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• pp.295-315
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• 2015

In order to determine the spatio-temporal distribution of macrobenthic faunal communities in Jinhae Bay, quantitative faunal samples were collected seasonally at 23 sites in Jinhae Bay from February, 2011 to November, 2012. Sediment facies were found to be mud except for those at Chilcheon-do near Geoje Island. Mean values of TOC (%) ranged between 1.3 and 3.6%, and these are the highest values recorded excluding special management areas in Korea. Hypoxia occurred every summer in the whole areas of Jinhae Bay except around Geoje Island in the bay mouth. Due to the summer hypoxia, species richness, density and biomass also declined during the summer in Jinhae Bay. Opportunistic species such as Paraprionospio patiens, Sigambra bassi, Nectoneanthes oxypoda and Theora fragilis occurred as the dominant species before and after the hypoxia. However, Capitella capitata appeared as a dominant species only during the winter-spring season every year. From cluster analysis, Jinhae Bay could be divided into two sites groups: one group occupied the normoxic zone and the other one located in the hypoxic zone.

• Proceedings of the KSPS conference
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• 2000.07a
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• pp.332-332
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• 2000

The purpose of this study is to investigate the perception and production of English vowels by native speakers of Korean. In perception test, twelve English vowels /${\ae},{\;}a,{\;}{\Game},{\;}e,{\;}{\varepsilon},{\;}i,{\;}I,{\;}a,{\;}o,{\;}u,{\wedge},{\;}{\mho}$/, as in had, hard, hoard, hayed, head, heed, hid, hod, hoed, whod, Hudd, and hood produced by native speakers of English were used as perception test materials and subjects were asked to identify the vowels. Two different groups of subjects participated in the perception test. One consisted of 90 students who were taking an English phonetics course, and the other consisted of 64 who were not. The results showed that the former did better than the latter m identifYing English vowels, and that vowels in 'head' and 'had' were relatively hard to identify, while vowels in 'hayed', 'hard', and unexpectedly, 'heed' and hid' were easy to perceive. In production test, two native English speakers and 4 native Korean speakers served as subjects. The 4 native Korean speakers were divided into two groups as in the perception test, experienced and inexperienced, depending on whether they were taking an English phonetics course or not. Native English speakers generally showed significant differences both in vowel duration and in FI & F2 values between members of the vowel pairs which are of special interest of this study: /i/ vs. /I/, /${\ae}$/ vs. /$\varepsilon$/, and /u/ vs. and /$\mho$/. There was no significant difference between the two Korean groups. Native Korean speakers showed much difference in neither duration nor FI & F2 values except significant durational difference in /i/ vs. /I/ pair.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.1
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• pp.1-11
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• 2016

Traditional costumes have evolved while reflecting the social, cultural and psychological values of the era. Costumes gain meaning by being worn that also allows their various symbolic meanings to be derived. Costumes worn in festivals by specific societies and organizations have especially apparent symbolism pertaining to their purpose. Most countries have traditional festivals that embody the country's distinct culture, history and traditions. These festivals are acts of consciousness expressing a special meaning of the community. Costumes represent a glimpse of life and culture during a festival period; in addition, the costume's style, color elements and decorations are expressions of community values and a distinct symbolic mechanism. Totemism (a significant element of these festivals) has been passed down for many generations. The current costumes for Totemism are distinct (compared to normal festival costumes) and embody a more symbolic meaning. This study deduces the exaggerated style, the concealment and disguise of the human body, and the pursuit of pleasure expressed in the Totemism costumes of regional European festivals. The symbolization theories of C. G. Jung and an analysis of Totemism costumes allow an understanding of their existential significance, their role as the medium between consciousness and unconsciousness, their meaning of symbolic transcendental unity, and their meaning of giving consciousness to the mind.

• Geomechanics and Engineering
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• v.10 no.2
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• pp.189-205
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• 2016

Soils are subjected to additional stresses due to the loads transferred by the foundations of the buildings. The distribution of stress in soil has great importance in geotechnical engineering projects such as stress, settlement and liquefaction analyses. The purpose of this study is to examine the shear stresses on horizontal plane below the rectangular foundations subjected to biaxial bending on an elastic soil. In this study, closed-form analytical solutions for shear stresses in x and y directions were obtained from Boussinesq's stress equations. The expressions of analytical solutions were simplified by defining the shear stress influence values ($I_1$, $I_2$, $I_3$), and solution charts were presented for obtaining these values. For some special loading conditions, the expressions for shear stresses in the soil below the corners of a rectangular foundation were also given. In addition, a computer program was developed to calculate the shear stress increment at any point below the rectangular foundations. A numerical example for illustrating the use of the presented solution charts was given and, finally, shear stress isobars were obtained for the same example by a developed computer program. The shear stress expressions obtained in this work can be used to determine monotonic and cyclic behavior of soils below rectangular foundations subjected to biaxial bending.