• Title/Summary/Keyword: 3D dimension

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A Study on Construction and Application of Nuclear Grade ESF ACS Simulator (원자력등급 ESF 공기정화계통 시뮬레이터 제작 및 활용에 관한 연구)

  • Lee, Sook-Kyung;Kim, Kwang-Sin;Sohn, Soon-Hwan;Song, Kyu-Min;Lee, Kei-Woo;Park, Jeong-Seo;Hong, Soon-Joon;Kang, Sun-Haeng
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.8 no.4
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    • pp.319-327
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    • 2010
  • A nuclear plant ESF ACS simulator was designed, built, and verified to perform experiment related to ESF ACS of nuclear power plants. The dimension of 3D CAD model was based on drawings of the main control room(MCR) of Yonggwang units 5 and 6. The CFD analysis was performed based on the measurement of the actual flow rate of ESF ACS. The air flowing in ACS was assumed to have $30^{\circ}C$ and uniform flow. The flow rate across the HEPA filter was estimated to be 1.83 m/s based on the MCR ACS flow rate of 12,986 CFM and HEPA filter area of 9 filters having effective area of $610{\times}610mm^2$ each. When MCR ACS was modeled, air flow blocking filter frames were considered for better simulation of the real ACS. In CFD analysis, the air flow rate in the lower part of the active carbon adsorber was simulated separately at higher than 7 m/s to reflect the measured value of 8 m/s. Through the CFD analyses of the ACSes of fuel building emergency ventilation system, emergency core cooling system equipment room ventilation cleanup system, it was confirmed that all three EFS ACSes can be simulated by controlling the flow rate of the simulator. After the CFD analysis, the simulator was built in nuclear grade and its reliability was verified through air flow distribution tests before it was used in main tests. The verification result showed that distribution of the internal flow was uniform except near the filter frames when medium filter was installed. The simulator was used in the tests to confirm the revised contents in Reg. Guide 1.52 (Rev. 3).

The Effect of Pervious Pavement on Reducing the Surface Runoff (투수성 포장재의 우수 표면유출 저감 효과)

  • Lee, Chun-Seok;Ryu, Nam-Hyung;Han, Seung-Ho
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.11 no.6
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    • pp.26-37
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    • 2008
  • The purpose of the study was to evaluate the effect of pervious pavements on reducing the surface runoff caused by rainfall. The surface runoff from twelve steel experimental beds with different pavement had been recorded every minute from May to September 2008, by the measuring system of tipping buckets(0.1mm/count) and data aquisition systems(National Instrument's Labview and DAQ boards & Autonics PR12-4). The dimension of the experimental bed was $1.5m(W){\times}2.0m(L){\times}0.6m(D)$ and eleven different kinds of vegetational(grass, grass+cubic stone, grass+hole brick), modular(brick, cubic stone, small cubic stone, wood block, interlocking block, clay brick, granular clay brick) and granular(naked soil, gravel) paving materials and concrete were applied for the comparison. Six rain events with depth over 30mm were selected and compared. The maximum depth of the rainfall selected was 137.5mm for 28 hours, and the minimum 30mm for 5 hours. The maximum rainfall per hour was 23mm/hr and the minimum 11.4mm/hr. The major findings were as follows; 1. All pervious pavement applied reduced over 75% of the surface runoff compared with concrete pavement. The grassy and porous pavements were relatively efficient in reducing surface runoff. 2. The grass was the more efficient as intercepting average 69.5mm of initial surface runoff, and maximum 77.8mm at the condition of 13.5mm/hr rainfall. The next was gravel intercepting maximum 65.5mm at the condition of 13.5mm/hr and the 40.9mm at 19.1mm/hr, average 55.7mm. 3. The modular pavements common in urban area were not good in intercepting the runoff except the 'clay granular brick' compared with others. The 'clay granular brick' showed relatively efficient intercepting average 14.1mm, which was the bigger amount than the 'grass+hole brick'. 4. The 'naked soil' were more effective than the 'concrete', 'brick', and 'interlocking block' in reducing the surface runoff, but less efficient than other materials. The capacity of the 'naked soil' to intercept the initial rainfall was similar to the 'brick'. As summary, the more grassy and porous pavement shows more effective in reducing surface runoffs.

Weight Control Behaviors, Health-related Quality of Life and Nutritional Status by Overestimation of Body Image among Young Korean Females: Data from the Fifth Korea National Health and Nutrition Examination Survey, 2010-2011 (20·30대 여성의 체형 과대인식에 따른 체중조절행위, 삶의 질, 식행동 및 영양소 섭취상태: 2010-2011년 국민건강영양조사 자료 이용)

  • Park, Seulki;Hyun, Taisun;Lee, Hongmie
    • Korean Journal of Community Nutrition
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    • v.20 no.5
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    • pp.362-374
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    • 2015
  • Objectives: This study was performed to investigate the effects of overestimation of their own body shape on weight control behaviors, mental condition, physical activity, dietary behavior, health-related quality of life, and nutritional status among young Korean females. Methods: A total of 1,514 women aged 20-39 years who are not pregnant and lactating among those who participated in the Fifth Korea National Health and Nutrition Examination Survey (2010~2011), were analyzed and grouped into underestimation (n=120), normal estimation (NE, n=840), and overestimation (OE, n=554), based on their body perception compared to actual percent ideal body weights. Variables were compared between OE group and NE group. Results: The subjects in OE group were significantly younger (29.5 vs. 30.5 years, respectively p < 0.05) and had lower body mass index (20.9 vs. 22.2 respectively, p < 0.01), health-related quality of life measured by EQ-5D (EuroQol-5 Dimension)(0.97 vs. 0.98 respectively, p < 0.05), nutrition adequacy ratio (NAR) of protein (0.91 vs. 0.93 respectively, p < 0.05), phosphorous (0.93 vs. 0.96 respectively, p < 0.05), and iron (0.70 vs. 0.75 respectively, p < 0.01), and index of nutrition quality (INQ) of iron (0.84 vs. 0.89 respectively, p < 0.05) compared to those in the NE group. The results of logistic regression showed that unmarried status (OR 1.32; 1.01~1.72) and severely underweight/underweight status (OR 1.94; 1.01~3.75)/(OR 1.81; 1.34~2.45) were significantly related to the probability of overestimation by the subjects. Significantly more women in OE group practiced fasting, skipping meals, and taking prescribed pills to lose body weights and had skipped breakfast compared to those in the NE group. Conclusions: The results of this study suggested that the Korean young women's distorted perception of own body shape may be associated with undesirable weight control behavior, low quality of life, and lower nutritional status. Therefore, nutrition education for this group should include information on correct body shape perception and its importance.

Multivariate Time Series Simulation With Component Analysis (독립성분분석을 이용한 다변량 시계열 모의)

  • Lee, Tae-Sam;Salas, Jose D.;Karvanen, Juha;Noh, Jae-Kyoung
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.694-698
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    • 2008
  • In hydrology, it is a difficult task to deal with multivariate time series such as modeling streamflows of an entire complex river system. Normal distribution based model such as MARMA (Multivariate Autorgressive Moving average) has been a major approach for modeling the multivariate time series. There are some limitations for the normal based models. One of them might be the unfavorable data-transformation forcing that the data follow the normal distribution. Furthermore, the high dimension multivariate model requires the very large parameter matrix. As an alternative, one might be decomposing the multivariate data into independent components and modeling it individually. In 1985, Lins used Principal Component Analysis (PCA). The five scores, the decomposed data from the original data, were taken and were formulated individually. The one of the five scores were modeled with AR-2 while the others are modeled with AR-1 model. From the time series analysis using the scores of the five components, he noted "principal component time series might provide a relatively simple and meaningful alternative to conventional large MARMA models". This study is inspired from the researcher's quote to develop a multivariate simulation model. The multivariate simulation model is suggested here using Principal Component Analysis (PCA) and Independent Component Analysis (ICA). Three modeling step is applied for simulation. (1) PCA is used to decompose the correlated multivariate data into the uncorrelated data while ICA decomposes the data into independent components. Here, the autocorrelation structure of the decomposed data is still dominant, which is inherited from the data of the original domain. (2) Each component is resampled by block bootstrapping or K-nearest neighbor. (3) The resampled components bring back to original domain. From using the suggested approach one might expect that a) the simulated data are different with the historical data, b) no data transformation is required (in case of ICA), c) a complex system can be decomposed into independent component and modeled individually. The model with PCA and ICA are compared with the various statistics such as the basic statistics (mean, standard deviation, skewness, autocorrelation), and reservoir-related statistics, kernel density estimate.

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Simulation of the effect of inclusions length and angle on the failure behavior of concrete structure under 3D compressive test: Experimental test and numerical simulation

  • Mohammad Saeed, Amini;Vahab, Sarfarazi;Kaveh, Asgari;Xiao, Wang;Mojtaba Moheb, Hoori
    • Steel and Composite Structures
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    • v.46 no.1
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    • pp.53-73
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    • 2023
  • Man-made structure materials like concrete usually contain inclusions. These inclusions affect the mechanical properties of concrete. In this investigation, the influence of inclusion length and inclination angle on three-dimensional failure mechanism of concrete under uniaxial compression were performed using experimental test and numerical simulation. Approach of acoustic emission were jointly used to analyze the damage and fracture process. Besides, by combining the stress-strain behavior, quantitative determination of the thresholds of crack stress were done. concrete specimens with dimensions of 120 mm × 150 mm × 100 mm were provided. One and two holes filled by gypsum are incorporated in concrete samples. To build the inclusion, firstly cylinder steel tube was pre-inserting into the concrete and removing them after the initial hardening of the specimen. Secondly, the gypsum was poured into the holes. Tensile strengths of concrete and gypsum were 2.45 MPa and 1.5 MPa, respectively. The angle bertween inclusions and axial loadind ary from 0 to 90 with increases of 30. The length of inclusion vary from 25 mm to 100 mm with increases of 25 mm. Diameter of the hole was 20 mm. Entirely 20 various models were examined under uniaxial test. Simultaneous with experimental tests, numerical simulation (Particle flow code in two dimension) were carried out on the numerical models containing the inclusions. The numerical model were calibrated firstly by experimental outputs and then failure behavior of models containing inclusions have been investigated. The angle bertween inclusions and axial loadind vary from 0 to 90 with increases of 15. The length of inclusion vary from 25 mm to 100 mm with increases of 25 mm. Entirely 32 various models were examined under uniaxial test. Loading rate was 0.05 mm/sec. The results indicated that when inclusion has occupied 100% of sample thickness, two tensile cracks originated from boundaries of sample and spread parallel to the loading direction until being integrated together. When inclusion has occupied 75% of sample thickness, four tensile cracks originated from boundaries of sample and spread parallel to the loading direction until being integrated together. When inclusions have occupied 50% and 25% of sample thickness, four tensile cracks originated from boundaries of sample and spread parallel to the loading direction until being integrated together. Also the inclusion was failed by one tensile crack. The compressive strength of samples decease with the decreases of the inclusions length, and inclusion angle had some effects on that. Failure of concrete is mostly due to the tensile crack. The behavior of crack, was affected by the inclusion length and inclusion number.

A Pilot Study of Evaluating the Reliability and Validity of Pattern Identification Tool for Insomnia and Analyzing Correlation with Psychological Tests (불면증 변증도구 신뢰도와 타당도 평가 및 심리검사와의 상관성에 대한 초기연구)

  • Jeong, Jin-Hyung;Lee, Ji-Yoon;Kim, Ju-Yeon;Kim, Si-Yeon;Kang, Wee-Chang;Lim, Jung Hwa;Kim, Bo Kyung;Jung, In Chul
    • Journal of Oriental Neuropsychiatry
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    • v.31 no.1
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    • pp.1-12
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    • 2020
  • Objectives: The purpose of this study was to evaluate the reliability and validity of the instrument on pattern identification for insomnia (PIT-Insomnia) and verify the correlation between PIT-Insomnia and psychological tests. Methods: Two evaluators examined the pattern identification of the participants who met insomnia disorder diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorder, Fifth Edition (DSM-5) and took the Insomnia Severity Index (ISI) score over 15 once manually and twice using the PIT-Insomnia to measure the inter-rater and test-retest reliability. We also conducted the following surveys: the Pittsburgh Sleep Quality Index (PSQI), the Korean version of Beck's depression inventory (K-BDI), the Korean version of the State-Trait Anxiety Inventory (STAI-K), the Korean Symptom checklist-95 (KSCL-95), and the EuroQol-5 dimension (EQ-5D), to measure concurrent validity and correlation between the PTI-Insomnia and psychological tests. Results: 1. The test-retest reliability analysis of the pattern identification results showed moderate agreement, and test-retest reliability analysis of each pattern identification score showed agreements from poor to moderate. 2. The inter-rater reliability analysis of the pattern identification results via manual showed slight agreement, when analysis was performed with calibration, the inter-rater reliability analysis of the pattern identification results via manual showed fair agreement. 3. The concordance analysis between results via manual and the PIT-Insomnia showed poor agreement, when the analysis was performed with calibration, concordance analysis showed fair agreement. 4. The concordance analysis between the PIT-Insomnia and the PSQI showed positive linear correlation. 5. The concordance analysis between the PIT-Insomnia and the PSQI, K-BDI, STAI-K, KSCL-95, and EQ-5D showed that non-interaction between the heart and kidney have positive linear correlation with the K-BDI, anxiety item of KSCL-95, dual deficiency of the heart-spleen have positive linear correlation with somatization item of KSCL-95, paranoia item of KSCL-95, heart deficiency with timidity have positive linear correlation with stress vulnerability item of KSCL-95, parania item of KSCL-95, phlegm-fire harassing the heart have positive linear correlation with K-BDI, paranoia item of KSCL-95, depressed liver qi transforming into fire have positive linear correlation with the anxiety item of KSCL-95, parania item of KSCL-95, all pattern identification have negative linear correlation with EQ-5D. Conclusions: The PIT-Insomnia has moderate agreement of reliability and reflects the severity of insomnia since it has some concurrent validity with the PSQI. There are some correlations between the PTI-Insomnia with specific psychological tests, so we could suggest it can be used appropriately in the clinical situation.

A Study on the morphologic characteristics of each constitution's trunk (체간부의 사상체질별 형태학적 특징에 관한 연구)

  • Hong, Suck-chull;Lee, Su-kyung;Lee, Eui-joo;Han, Gi-hwan;Chou, Yong-jin;Choi, Chang-seok;Koh, Byung-hee;Song, Il-byung
    • Journal of Sasang Constitutional Medicine
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    • v.10 no.1
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    • pp.101-142
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    • 1998
  • 1. Objects The base of classification of Sasang Constitution was the different congenital formation of organs such as lungs, spleen, liver, kidneys, and it was expanded from the viscera region of lungs, spleen, liver, kidneys to the body shape of trunk. The researched about body shape of Sasang Constitution have had points of issues which derived by measurement with hands. But this study was measured the characteristics of body shape putting in importance of anatomical position with the computerized 3-Dimension scanner, which minimized the errors of measurement, and it was abled the cubic measurement such as volume, area of cross section as well as round length. 2. Materials & Method The examinee was healthy male 40 persons and female 20 persons from 20's to 40's, who was diagnosed by the specialist of Sasang Constitutional Medicine. The body shape was measured round length, area of cross section, and volume of 31 anatomical points and the 25 hypothesis with the Rapid 3D Color Scanner Model 3030 RGB/PS. And the characteristics of each constitution's body shape was derived. 3. Results & Concousion In female, Taeumin had the largest trunk and Soeumin had the smallest trunk compared to other constitution, but Soyangin had only the smallest neck. Soeumin has the smallest round length of nipple and the $CV_{12}$, and Soyangin has the smallest breadth of ASIS. Soyangin had the smallest volume from thyroid bone to the highest points of armpits and from sternum to nipple. Taeumin had the largest volume from sternum to the $CV_{12}$ and from sternum to xiphoid process. In male, Taeumin had the largest trunk and Soeumin had the smallest trunk from the level of thyroid bone to ASIS. Soyangin has the longest distance and Soeumin has the shortest distance from nipple to the lowest of breast. Taeumin had the largest volume of trunk and Soeumin had the smallest volume of trunk. In the ration of four-Cho, Taeumin had the longest distance from the highest points of armpits to nipple and Soyangin had the shortest distance of that. Soyangin had the smallest ratio of the height of upper middle cho. Soeumin had the smallest ratio from the $CV_{12}$ to navel among trunk. In the correlation among the four Cho, Taeumin had the negative correlation between the Upper-Cho and the Lower-Middle-Cho significantly.

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Relationship Analysis between Lineaments and Epicenters using Hotspot Analysis: The Case of Geochang Region, South Korea (핫스팟 분석을 통한 거창지역의 선구조선과 진앙의 상관관계 분석)

  • Jo, Hyun-Woo;Chi, Kwang-Hoon;Cha, Sungeun;Kim, Eunji;Lee, Woo-Kyun
    • Korean Journal of Remote Sensing
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    • v.33 no.5_1
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    • pp.469-480
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    • 2017
  • This study aims to understand the relationship between lineaments and epicenters in Geochang region, Gyungsangnam-do, South Korea. An instrumental observation of earthquakes has been started by Korea Meteorological Administration (KMA) since 1978 and there were 6 earthquakes with magnitude ranging 2 to 2.5 in Geochang region from 1978 to 2016. Lineaments were extracted from LANDSAT 8 satellite image and shaded relief map displayed in 3-dimension using Digital Elevation Model (DEM). Then, lineament density was statistically examined by hotspot analysis. Hexagonal grids were generated to perform the analysis because hexagonal pattern expresses lineaments with less discontinuity than square girds, and the size of the grid was selected to minimize a variance of lineament density. Since hotspot analysis measures the extent of clustering with Z score, Z scores computed with lineaments' frequency ($L_f$), length ($L_d$), and intersection ($L_t$) were used to find lineament clusters in the density map. Furthermore, the Z scores were extracted from the epicenters and examined to see the relevance of each density elements to epicenters. As a result, 15 among 18 densities,recorded as 3 elements in 6 epicenters, were higher than 1.65 which is 95% of the standard normal distribution. This indicates that epicenters coincide with high density area. Especially, $L_f$ and $L_t$ had a significant relationship with epicenter, being located in upper 95% of the standard normal distribution, except for one epicenter in $L_t$. This study can be used to identify potential seismic zones by improving the accuracy of expressing lineaments' spatial distribution and analyzing relationship between lineament density and epicenter. However, additional studies in wider study area with more epicenters are recommended to promote the results.

Applying QFD in the Development of Sensible Brassiere for Middle Aged Women (QFD(품질 기능 전개도)를 이용한 중년 여성의 감성 Brassiere 개발)

  • Kim Jeong-hwa;Hong Kyung-hi;Scheurell Diane M.
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.12 s.138
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    • pp.1596-1604
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    • 2004
  • Quality Function Deployment(QFD) is a product development tool which ensures that the voice of the customer needs is heard and translated into products. To develop a sensible brassiere for middle-aged women QFD was adopted. In this study the applicability and usefulness of QFD was examined through the engineering design process for a sensible brassiere for middle-aged women. The customer needs for the wear comfort of brassiere was made by one-on-one survey of 100 women who aged 30-40. The customer competitive assessment was generated by wearing tests of 10 commercial brassieres. The subjective assessment was conducted in the enviornmental chamber that was controlled at $28{\pm}1^{\circ}C,\;65{\pm}3\%RH.$ As a results, we developed twenty-one customer needs and corresponding HOWs for the wear comfort of brassiere. The Customer Competitive Assessment was generated by wearing tests of commercial brassiere. The subjective measurement scale and dimension for the evaluation of sensible brassiere were extracted from factor analysis. Four factors were fitting, aesthetic property, pressure sensation, displacement of brassiere due to movement. The most critical design parameter was wire-related property and second one was stretchability of main material of brassiere. Also, wearing comfort of brassiere was affected by the interaction of initial stretchability of wing and support of strap. Engineering design process, QFD was applicable to the development of technical and aesthetic brassieres.

Tie Spatial Structure of Ch'ang-ts'ai-ts'un Village A Case Study on a Rural Village of Korean Immigrants in Yen-pien Area of China (중국(中國) 연변지구(延邊地區) 조선족(朝鮮族)마을의 구성(構成) 룡정시 지신향 장재촌을 대상으로)

  • Lee, Kyu Sung
    • Journal of architectural history
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    • v.3 no.1
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    • pp.83-99
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    • 1994
  • Ch'ang-Ts'al-Ts'un is a rural Village near Lung-jing City in Yen-pien Korean Autonomous Province of China. It was formed about 100 years ago by Korean Immigrants and has been developed maintaing the characteristics of traditional Korean architecture. Therefore investigating the spatial structure of this village is a meanigful work to confirm and explore one branch of Korean architecture. This study aims at analyzing the spatial structure of the village using direct data collected from the field work and indirect data from books and maps. The field work consists of on-the-site survey of the village layout, interviews of residents, observation notes and photography. Ch'ang-Ts'ai-Ts'un is located 360-370 m high above the sea level and at the side of a long valley. A river flows in the middle of the valley and relatively flat arable land exists at the both sides of the river. The location of the village related to the surrounding river and mountains suggests that the site of the village was chosen according to Feng-Shui, Chinese and Korean traditional architectural theory. The main direction of the house layouts is South-western. The village has been growing gradually until today. Therefore it is meaningful to make the village layout before Liberation(1946 A.D.) because the characteristics of Korean architecture prevailed more in that period. The area of the previous village is limited to the west side of the creek. New houses were later added to the east of the creek, forming a 'New Village'. Previously the village was composed of 3 small villages: Up, Middle and Down. Also the main access roads connecting the village with the neighboring villages were penetrating the village transversely. Presently the main access road comes to the village longitudinally from the main highway located in front of the village. The retrospective layout shows the existence of well-formed Territory, Places and Axes, thus suggesting a coherent Micro-cosmos. The boundary of imaginery territory perceived by present residents could be defined by linking conspicous outside places sorrounding the village such as Five-mountains, Front-mountain, Shin-dong village, Standing-rock, Rear-mountain and Myong-dong village. Inside the territory there are also the important places such as Bus-stop, Memorial tower of patriots, Road-maitenance building and the village itself. And inside it 5 transverse and 1 longitudinal axes exist in the form of river, roads and mountains. The perceived spatial structure of the village formed by Places, Axes and Territory is geometrical and well-balanced and suggests this village is fit for human settlement. The administrative area of the village is about 738 ha, 27 % of which is cultivated land and the rest is mountain area. Initially the village and surrounndings were covered with natural forest But the trees have been gradually cut down for building and warning houses, resulting in the present barren and artificial landscape with bare mountains and cultivated land. At present the area of the village occupied by houses is wedge-shaped, 600 m wide and 220 m deep in its maximum. The total area of the village is $122,175m^{2}$. The area and the rate of each sub-division arc as follow. 116 house-lots $91,465m^{2}$ (74.9 %) Land for public buildings and shops $2,980m^{2}$ (2.4 %) Roads $17,106m^{2}$ (14.0 %) Creek $1,356m^{2}$ (1.1 %) Vacant spaces and others $9,268m^{2}$ (7.6 %) TOTAL $122,175m^{2}$ (100.0 %) Each lot is fenced around with vertical wooden pannels 1.5-1.8 m high and each house is located to the backside of the lot. The open space of a lot is sub-divided into three areas using the same wooden fence: Front yard, Back yard and Access area. Front and back yards are generally used for crop-cultivation, the custom of which is rare in Korea. The number of lots is 116 and the average size of area is $694.7m^{2}$. Outdoor spaces in the village such as roads, vacant spaces, front yard of the cultural hall, front yard of shops and spacse around the creek are good 'behavioral settings' frequently used by residents for play, chatting, drinking and movie-watching. The road system of the village is net-shaped, having T-junctions in intersections. The road could be graded to 4 categories according to their functions: Access roads, Inner trunk roads, Connecting roads and Culs-de-sac. The total length of the road inside the village is 3,709 m and the average width is 4.6 m. The main direction of the road in the village is NNE-SSE and ESE-WNW, crossing with right angles. Conclusively, the spatial structure of Ch'ang-Ts'ai-Ts'un village consists of various components in different dimensions and these components form a coherent structure in each dimension. Therefore the village has a proper spatial structure meaningful and appropriate for human living.

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