• Title/Summary/Keyword: span variability

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Chronic Aircraft Noise Exposure and Sustained Attention, Continuous Performance and Cognition in Children (만성 항공기 소음 노출과 아동의 지속주의력과 연속수행능력 및 인지기능)

  • Lim, Myung-Ho;Park, Young-Hyun;Lee, Woo-Chul;Paik, Ki-Chung;Kim, Hyun-Woo;Kim, Hyun-Joo;Rho, Sang-Chul;Kim, Hae-Young;Kwon, Ho-Jang
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.18 no.2
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    • pp.145-153
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    • 2007
  • Objectives: This study was focused on the influence of chronic aircraft noise exposure on children's continuous performance, intelligence and reading skill. Methods: We enrolled 586 children in 4-6th grade of 7 primary schools near air base in Korea. Continuous performance was measured using the computerized ADS program. We analyzed 477-512 children on the visual continuous performance test, auditory continuous performance test, intelligence test, and reading and the vocabulary test. Intelligence was measured using vocabulary, digit span, block design, and digit symbol tests of K-WISC-III. Results: The commission error and variability deviation of auditory continuous performance test and reading test were significantly higher among children in schools with the helicopter noise and the fighting plane noise compared to children in the low noised schools. Conclusion: There was a possibility that chronic aircraft noise exposure was associated with impairment of the school performance. The result of our study also shows chronic aircraft noise was associated with reading ability.

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A Numerical Study on the Apartment Structure Using Crossed Wide Girder (교차형 와이드 거더를 이용한 아파트구조의 수치해석적 연구)

  • Park, Jung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.5
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    • pp.1186-1191
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    • 2007
  • The study uses the crossed wide girder(waffle slab type) in apartment structural system comparing with existing shear wall system. The crossed wide girder will be able to secure the span of the longest which is possible with minimum slab thickness by not increasing the height. The research sees continuity arranges the crossed wide girder in schedule interval following the stress distribution. Namely, it is to make the interior space with the space without column and wall in the minimum height. In order to check the numerical value of this study which it interpreted the ductile frame system due to the crossed wide girder and existing shear wall system used the Midas Gen is a program which 3-dimension laterial force designs are possible. Analysis results, the crossed wide girder system is not disadvantageously laterial drift, drift ratio and deflection of slab compares with existing shear wall system. Also the whole concrete amount is similar existing shear wall system. The crossed wide girder is advantage which secure a architectal variability.

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Understanding elderly's travel pattern based on individual trip trajectory using smart card data (스마트카드 데이터를 활용한 통행궤적 기반 고령인구 통행유형 분류)

  • Lee, Ju-Yoon;Kang, Young-Ok
    • Journal of Cadastre & Land InformatiX
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    • v.52 no.2
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    • pp.153-169
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    • 2022
  • With the extension of the average life span and the rapid aging of the population, defining elderly population as a single group is difficult as the physical, economic and social conditions of individual have become different. Therefore, policies that take into account the characteristics of each group are required. The purpose of this study is to classify individual travel types and to analyze the characteristics of each travel type, based on individual public transportation trajectory data as known as smart card data. Among the four classified types, the long-distance low-frequency stay type and the short-range medium-frequency mobile type show external activity traffic characteristics for retirement leisure, while the long-distance high-frequency stay type and the long-distance high-frequency mobile group include regular commuting. Traffic variability and residence areas of stay were identified in terms of each classified travel type. The results of this study provide the important suggestions for establishing a transportation policy that takes into account the characteristics of each type of elderly population in Seoul.

Seismic Behavior of Bridges Considering Ground Motion Spatial Variation (공간적으로 변화하는 입력지진으로 인한 교량의 지진거동특성)

  • Bae, Byung Ho;Choi, Kwang Kyu;Kang, Seung Woo;Song, Si Young
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.4
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    • pp.759-768
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    • 2015
  • The ground motions of large dimensional structures such as long span bridges at different stations during an earthquake, are inevitably different, which is known as the ground motion spatial variation effect. There are many causes that may result in the spatial variability in seismic ground motion, e.g., the wave passage effect due to the different arrival times of waves at different locations; the loss of coherency due to seismic waves scattering in the heterogeneous medium of the ground; the site amplification effect owing to different local soil properties. In previous researches, the site amplification effects have not been considered or considered by a single-layered soil model only. In this study, however, the ground motion amplification and filtering effects are evaluated by multi-layered soil model. Spatially varying ground motion at the sites with different number of layers, depths, and soil characteristics are generated and the variation characteristics of ground motion time histories according to the correlation of coherency loss function and soil conditions are evaluated. For the bridge system composed of two unit bridges, seismic behavior characteristics are analyzed using the generated seismic waves as input ground motion. Especially, relative displacement due to coherency loss and site effect which can cause the unseating and pounding between girders are evaluated. As a result, considering the soil conditions of each site are always important and should not be neglected for an accurate structural response analysis.

'Development' and 'Relations', as the Core Concepts of Home Economics in 2015 Revised Middle School Curriculum in Korea (2015 개정 가정과의 핵심개념 '발달과 관계' - 중학교 교육과정을 중심으로 -)

  • Lim, JungHa;Jun, Mi-Kyung
    • Journal of Korean Home Economics Education Association
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    • v.28 no.1
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    • pp.1-17
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    • 2016
  • The purpose of this review was to introduce and examine 'development' and 'relations' as the core concepts of Home Economics in 2015 revised middle school curriculum in Korea. The 2009 and 2015 proclamation of the ministry of education on home economics curriculum and 26 published middle school textbooks were reviewed. The major findings were as follows. First, the components of human 'development' and family 'relations' were strongly associated with promoting four key competencies (i.e. the self-management competency, the communication competency, the aesthetic sensibility competency, the community competency) of 2015 revision. Also, four of cross-curricular learning topics (i.e. character education, multicultural education, safety and health education, human right education) in 2015 revision could be effectively discussed with human 'development' and family 'relations'. Second, when teaching and learning of the core concept, human 'development', continuous dynamic aspects of life-span development, the connectedness of different domains of development, systematic approach of various concepts in development, specificity and empirical evidence of information and variability of developmental patterns in adolescence should be considered. Third, when teaching and learning of the core concept, family 'relations', family trait such as generational relations, gender relations, role relations and power relations should be taken into account. In addition, exclusively focusing on normal family ideology or image of middle-class family and lecture-centered instruction methods should be changed for students to achieve the competencies relevant to family relations. The future directions for applying core concepts, 'development' and 'relations' in classroom will be discussed.

A Comparative Study on the Life Cycle Cost of Wall Type Apartment and Beam-Column Structural Apartment (생애주기비용 분석을 통한 벽식 구조 공동주택과 장수명 공동주택의 경제성 비교 연구)

  • Lee, Jeehee;Kim, Kyuree;Son, JeongWook;Yi, June-Seong
    • Korean Journal of Construction Engineering and Management
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    • v.15 no.6
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    • pp.35-43
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    • 2014
  • Ministry of Land, Infrastructure and Transport (MOLIT) promote long-life housing to reduce social costs generated by poorly considered rebuilding and extend the life-span of housing. Long-life housing has advantages of durability, floor plan variability, efficient maintenance and ease of remodeling because it is a beam-column structure building. However, long-life housing requires somewhat higher initial construction cost than wall type apartments. It makes increase of long-life housing more difficult. In this study, we compare between wall-type apartment and beam-column structure apartment from Life-Cycle Cost's viewpoint. As a result of the study, long-life housing incurs 18% higher initial cost than wall type apartment, but is 7% more economical than wall type apartment in terms of Life Cycle Cost. Therefore, it is shown that long-life housing could be a beneficial alternative to traditional wall type apartments.

THE MILLIMETER-RADIO EMISSION OF BL LACERTAE DURING TWO γ-RAY OUTBURSTS

  • Kim, Dae-Won;Trippe, Sascha;Lee, Sang-Sung;Park, Jong-Ho;Kim, Jae-Young;Algaba, Juan-Carlos;Hodgson, Jeffrey A.;Kino, Motoki;Zhao, Guang-Yao;Wajima, Kiyoaki;Kang, Sincheol;Oh, Junghwan;Lee, Taeseok;Byun, Do-Young;Kim, Soon-Wook;Kim, Jeong-Sook
    • Journal of The Korean Astronomical Society
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    • v.50 no.6
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    • pp.167-178
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    • 2017
  • We present a study of the inexplicit connection between radio jet activity and ${\gamma}$-ray emission of BL Lacertae (BL Lac; 2200+420). We analyze the long-term millimeter activity of BL Lac via interferometric observations with the Korean VLBI Network (KVN) obtained at 22, 43, 86, and 129 GHz simultaneously over three years (from January 2013 to March 2016); during this time, two ${\gamma}$-ray outbursts (in November 2013 and March 2015) can be seen in ${\gamma}$-ray light curves obtained from Fermi observations. The KVN radio core is optically thick at least up to 86 GHz; there is indication that it might be optically thin at higher frequencies. To first order, the radio light curves decay exponentially over the time span covered by our observations, with decay timescales of $411{\pm}85$ days, $352{\pm}79$ days, $310{\pm}57$ days, and $283{\pm}55$ days at 22, 43, 86, and 129 GHz, respectively. Assuming synchrotron cooling, a cooling time of around one year is consistent with magnetic field strengths $B{\sim}2{\mu}T$ and electron Lorentz factors ${\gamma}$ ~ 10 000. Taking into account that our formal measurement errors include intrinsic variability and thus over-estimate the statistical uncertainties, we find that the decay timescale ${\tau}$ scales with frequency ${\nu}$ like ${\tau}{\propto}{\nu}^{-0.2}$. This relation is much shallower than the one expected from opacity effects (core shift), but in agreement with the (sub-)mm radio core being a standing recollimation shock. We do not find convincing radio flux counterparts to the ${\gamma}$-ray outbursts. The spectral evolution is consistent with the 'generalized shock model' of Valtaoja et al. (1992). A temporary increase in the core opacity and the emergence of a knot around the time of the second ${\gamma}$-ray event indicate that this ${\gamma}$-ray outburst might be an 'orphan' flare powered by the 'ring of fire' mechanism.

The Characteristics of Flexibility applied to Unit Plan of Housing by Residents Participation - focusing on European Multi-story Housing applying Residents Participation - (거주자 참여형 공동주거의 평면계획에 적용된 가변성의 특성 - 유럽의 거주자 참여형 다층 공동주거를 중심으로 -)

  • Kim, Hyun-Ju
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.34 no.11
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    • pp.113-123
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    • 2018
  • First of all, the multi-story Housing applying resident's participation in europe was classified by the menu selection method, the two-step supply method and the cooperative method. And then I analyzed flexible unit plan of cases for deriving the planning methode and the characteristics of flexibility. First, I analyzed the area and form of the unit plan, structure and Installation, fixed and variable elements to derive the planning method. The area of units are distributed from a minimum of $35m^2$ to a maximum of $150m^2$, and many of the unit planes have a narrow front and a deep depth. The structure is a long-span wall-structure or a skeleton structure, and is designed without any columns and bearing walls in the interior space for flexibility in spatial composition. The vertical shafts are located in the center of the unit in a box-form or in the corner at the unit dividing wall for free placement of interior wall. Fixed elements are framework and facility systems. Most of the future residents in the two-steps supply method and the cooperative method were able to freely design the internal space within the zoning concept proposed by the architect and change the location of the facade element within module system proposed by the architect. Second, the characteristics of the flexibility applied to the unit plan were divided in integrated flexibility, functional flexibility, construction flexibility, and supply flexibility. The integrated flexibility enables residents to give the variable space combination based on the complex structure of the inner space for providing various living experiences. Regarding functional flexibility, the three-dimensional spatial structure with neutral space has multi-functionality according to the needs of residents and easily accepts mixing of hybrid programs such as work and residence. Constructive flexibility allows residents to create identity by freely planning interior space and changing the size or location of facade components in a determined system of architects. Finally, various types of size and space composition are proposed and realized in the whole building applying menu selection method, so that flexibility in the offer can accommodate and integrate various types of living.

The Changes of Short-Term Memory and Autonomic Neurocardiac Function after 4-10Hz Sound and Light Stimulation - A Pilot Study - (4-10 Hz 빛과 소리자극 후 단기기억력 및 자율신경심장기능의 변화 - 예비연구 -)

  • Lee, Seung-Hwan;Kim, Jin-Hwan;Park, Joong-Kyu;Lee, Kyung-Uk;Yang, Dae-Hyun;Hong, Keun-Young;Chae, Jeong-Ho
    • Sleep Medicine and Psychophysiology
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    • v.11 no.1
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    • pp.29-36
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    • 2004
  • Objectives: Sound and light (SL) stimulation has been used as a method to induce some useful mental states in the fields of psychology and psychiatry. It is believed that sound and light entrainment device (SLED) has some specific effects through synchronization of EEG in patients who use it. Theta frequency is believed to stimulate deep relaxation and short term memory processing. This study was conducted to evaluate if 4-10 Hz SL stimulation can induce relaxation and improve short term memory function. Methods: Ten medical students with no medical or psychiatric problems participated in this study. Subjects were randomly divided into two groups. One group was applied with real SLED was applied to one group (R group) and pseudo SLED to the other group (P group). The two groups were exposed to SL stimulation with SLED 15 minutes a day for 5 days, and after two days rest the two groups were switched over. The Korean Wechsler Adult Intelligence Scale (K-WAIS), Academic Motivation Tests (AMT), Test Anxiety Scale (TAS), Korean Auditory Verbal Learning Test (K-AVLT), and digit span were used to evaluate short term memory. Spielberger's State-Trait anxiety inventory and heart rate variability (HRV) test were used to evaluate degree of relaxation. Results: Compared with S group, R group showed a significant improvement in K-AVLT and digit span after a single application of SL stimulation. But 5-day long application did not reveal any differences between the two groups. A significant change in HRV was observed in 5-day long application of SL stimulation after being switched over to other SLED. Conclusion: This pilot study suggests that 4-10 Hz SL stimulation has some positive influences on short term memory and relaxation.

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