• Title/Summary/Keyword: mixed type

Search Result 2,732, Processing Time 0.188 seconds

Semi-Active Control System Based on the Experimental Results of the Performance of a Small Scale MR Damper (소형 MR감쇠기의 성능 실험에 기초한 준능동 제어 시스템)

  • Min Kyung-Won
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.19 no.3 s.73
    • /
    • pp.233-238
    • /
    • 2006
  • In this paper, mixed mode magneto-rheological(MR) damper, which is applicable for vibration control of a small scale multi-story structure, is devised. First, the schematic configurations of the shear, flow, and mixed mode MR dampers are described with design constraints and then the analytical models to predict the field-dependent damping forces are derived for each type. Second, an appropriate size of the mixed mode MR damper is manufactured and its field-dependent damping characteristics are evaluated in time domain. Finally, the performance of the manufactured MR damper which is semi-actively applied to a small scale building excited by earthquake load, is numerically evaluated.

A Study on the Planning Characteristics of Interior Space Aiming for the Exterior Space in Mixed-Use Development (복합용도개발 내부공간의 외부공간 지향성에 관한 계획특성 연구)

  • Kim, Suk-Ki;Sung, Lee-Yong
    • Korean Institute of Interior Design Journal
    • /
    • v.22 no.3
    • /
    • pp.43-51
    • /
    • 2013
  • The purpose of this study is analysing the characteristics of interior space aiming for the exterior space in mixed-used development. The range of this study is limited as passage, department store, shoppingmall and Mixed Use Development. The method of this study is as follows. First, analysing the 7 samples of the interior space aiming for the exterior space in MXD through the framework of public character categorized as 5 factors, accessibility, openness, comfort properties, connectivity, convenience in use. Second, drawing a conclusion from the precedent step. The result of this study is as follows. First, the interior space has become bigger with time. And the public character is expanded with having the same structure of the city space. Second, the interior space solves the problem of the exterior space of city but prefers the same factors with the exterior space. Third, the street in the interior space has the characteristics of openness and comfort properties through diversification. And the open space is planned in various parts of the MXD and has the character of accessibility and connectivity.

Case Study of Flexural Strength Evaluation of Epoxy Injected Concrete Using Low Pressure Mixed with Mechanical High Pressure (기계식 고압과 저압을 혼용한 에폭시 주입 콘크리트의 휨강도 검토 사례 연구)

  • Hong, Ki-Nam;Yu, Yeon-Jong;Lee, Kang-Moon;Ryu, Chang-Yeol;Yoon, Hong-Su
    • Journal of the Korean Society of Safety
    • /
    • v.27 no.1
    • /
    • pp.49-54
    • /
    • 2012
  • The objective of this study is to investigate the capacity of epoxy injection method using low pressure mixed with high pressure. Injection depth test and flexural strength test were respectively performed on $40{\times}45{\times}35$ cm and $100{\times}10{\times}40$ cm specimens. Considered as the test variables were injection type(low pressure, low and high pressure), crack width(0.25 mm, 0.50 mm), injection direction(upper, lower, side), and epoxy viscosity(low, medium, high). Test results showed that low viscosity epoxy injection depth of injector using low pressure mixed with high pressure for upper direction were 23 cm and tension strength of crack face repaired by injector using low pressure mixed with high pressure was larger than that of concrete.

Study on the Classification of the Mixed-Use Development in terms of the Use and Function in Foreign Countries (해외 도심복합시설의 용도 및 기능에 따른 유형분류)

  • Lee, Ha-Shik;Jung, Bo-Ra;Choi, Young-O;Chae, Chang-U;Lee, Kang-Hee
    • Proceeding of Spring/Autumn Annual Conference of KHA
    • /
    • 2008.04a
    • /
    • pp.245-250
    • /
    • 2008
  • The city means not only a geographical area as a role of the spatial boundary, but also a socio-economic place to communicate with each part. It requires various functions to get the income and activities. But city has a limitation of a available land to provide the required function and a sufficient space to supply the activity. Therefore, the development trend of city has not been to spread to the horizontal area any more and considered the vertical area. In addition, various functions put into a massive building because many people want to solve the daily requirements without spending time and cost. In this paper, it aimed at classifying the mixed-use building into function, circulation, relation between the public and private space and the building shape to provide the design information according to the development constraints such as land area, functional limitation, accessibility, etc. The classification of the mixed-use buildings is divided into four areas. The data are collected with foreign countries in Japan, Europe and US.

  • PDF

Hydrostatic Pressure Resistance Performance Testing of Cement Mixed Siliceous Powder Waterproofing Coationgs (규산질계 분말형 도포방수재의 내투수성 성능평가 연구)

  • Park, So-Young;Kwon, Si-Won;Kim, Soo-Yeon;Kim, Byong-il;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2018.11a
    • /
    • pp.31-32
    • /
    • 2018
  • Lately, cement mixed siliceous powder waterproofing coating has been used as a waterproofing material in the wet environment condition of an underground concrete structure. Underground is exposed to environmental influences such as pressure of ground water, pressure of soil. However, the quality standard for pressure (water pressure, earth pressure) is not specified in the specification of the cement mixed siliceous powder waterproofing coating. Therefore, in this study, the permeability test was carried out based on the assumption that the durability should be verified in consideration of the environmental aspects of the material in actual field. As a result of the test, the permeability was generated from the inorganic single type material, but it was caused by the sealing failure and the test error, and the permeability was not generated in most of the materials. The results of this study will be analyzed by reviewing the physical properties of the material, and the research direction will be resumed.

  • PDF

Studies on the interaction of Azo dyes with cationic surfactant(1)

  • Cho, Yung-Mee;Lee, Wang-Kyu;Kim, Bak-Kwang
    • Archives of Pharmacal Research
    • /
    • v.4 no.2
    • /
    • pp.75-84
    • /
    • 1981
  • As the cetyltrimenthy ammonium bromide (CTAB) concentration increases to $2{\times}10^{-4}$/M the absorption maximum of ethyl orange (EO) makes a blue shift from 475 mm to 395 mm. At higher concentration of CTAB than $2{\times}10^{-4}$ / M the absorption maximum shifts to higher wavelength than 395 nm. A new peak at 395 nm is shown to result from the mixed micelle due to dye stacking interaction rather than from a change in dye geometry. Because Raman spectra of EO on interaction with varying amount of CTAB are similar to that of EO in water. EO retains trans azo type on interaction with CTAB. There is a change of c.m.c.s. of CTAB for the mixed micelle in the presence of salt. The effect of added salt on C. M. C. of CTAB for the mixed micelle is given that the logarithm of the c. m. c. is a linear function of the logarithm of the sum of the c. m. c. and the concentration of added salt.

  • PDF

Future Prospects of Forest Type Change Determined from National Forest Inventory Time-series Data (시계열 국가산림자원조사 자료를 이용한 전국 산림의 임상 변화 특성 분석과 미래 전망)

  • Eun-Sook, Kim;Byung-Heon, Jung;Jae-Soo, Bae;Jong-Hwan, Lim
    • Journal of Korean Society of Forest Science
    • /
    • v.111 no.4
    • /
    • pp.461-472
    • /
    • 2022
  • Natural and anthropogenic factors cause forest types to continuously change. Since the ratio of forest area by forest type is important information for identifying the characteristics of national forest resources, an accurate understanding of the prospect of forest type change is required. The study aim was to use National Forest Inventory (NFI) time-series data to understand the characteristics of forest type change and to estimate future prospects of nationwide forest type change. We used forest type change information from the fifth and seventh NFI datasets, climate, topography, forest stand, and disturbance variables related to forest type change to analyze trends and characteristics of forest type change. The results showed that the forests in Korea are changing in the direction of decreasing coniferous forests and increasing mixed and broadleaf forests. The forest sites that were changing from coniferous to mixed forests or from mixed to broadleaf forests were mainly located in wet topographic environments and climatic conditions. The forest type changes occurred more frequently in sites with high disturbance potential (high temperature, young or sparse forest stands, and non-forest areas). We used a climate change scenario (RCP 8.5) to establish a forest type change model (SVM) to predict future changes. During the 40-year period from 2015 to 2055, the SVM predicted that coniferous forests will decrease from 38.1% to 28.5%, broadleaf forests will increase from 34.2% to 38.8%, and mixed forests will increase from 27.7% to 32.7%. These results can be used as basic data for establishing future forest management strategies.

Molecular Dynamic Simulations of the Phase Transition of $\alpha-quartz$ and $\alpha-quartz-type$-type $GeO_2$ under High Pressure (고압력하에서의 $\alpha-quartz$$\alpha-quartz$$GeO_2$의 상전이에 관한 분자동력학시뮬레이션)

  • ;;;;河村雄;Zenbe-e Nakagawa
    • Journal of the Korean Ceramic Society
    • /
    • v.34 no.7
    • /
    • pp.713-721
    • /
    • 1997
  • Molecular dynamic (MD) simulations with new interatomic potential function including the covalent bond were performed on the phase transition of $\alpha$-quartz-type GeO2 under high pressure. The optimized crystal structure and the pressure dependence of the lattice constant showed higher reproducibility than the previous models and were in very good agreement with the experimental data. A phase transition of $\alpha$-quartz and $\alpha$-quartz-type GeO2 by simulation was found approximately 24 GPa and 6-7 GPa, respectively. This phase transition involved an abrupt volume shrinkage and showed 4-6 coordination mixed structure with the increasing in the coordination number of cation.

  • PDF

Optimized Production through Enlargement Comparison Grown in Various Mixed Soils using Tubers of In vitro Pinellia triparita(Blume) Schott (기내증식 대반하의 상토 조성별 괴경 비대 조건 비교를 통한 최적 배양묘 생산 조건 확립)

  • Lee, Ka Youn;Min, Ji Yun;Kim, Mi Sun;Moon, Byeong Cheol;Kang, Young Min
    • Journal of agriculture & life science
    • /
    • v.50 no.2
    • /
    • pp.33-43
    • /
    • 2016
  • Pinellia tripartita(Blume) Schott is a herbaceous perennial plant belonging to the Araceae and distributed on Asia including of Korea, Japan, and China. P. tripartita is often used for gardening but has not been developed mass-breeding methods. In this study, we compared the tuber growth in different combinations of mixed soils used six compositions. Tubers used to study was cultured in vitro and divided into two groups. Type I was diameter more than 1cm and the group of Type II was diameter below than 1cm. Enlargement of tubers and growth of aerial parts were measuring the plant height, number of fresh leaves and dead leaves, number of bullets, tuber size, and fresh / dry weight. The size/weight and numbers of tubers from the mixed soil B (coir 68.0%, peat moss 14.7%, perlite 3.0%, vermiculite 7.0% and zeolite 7.0%) were the best grown up for eight weeks. In case of Type I, GI (Growth index) of tuber size and weight were 45% and 101%, respectively. The difference of growth was doubled compared to the bad growth treatment as the mixed soil E(Coir 14.3%, peat moss 14.3%, perlite 42.9%, vermiculite 14.3%, and zeolite 14.3%). These results could be used as the basic information for the similar experimental design for the P. ternata.

A Study on Prevalence and Characteristics of Headache (두통의 특성에 관한 연구)

  • Hyun-Koo Kim;Bo-Young Um;Sung-Chang Chung
    • Journal of Oral Medicine and Pain
    • /
    • v.18 no.2
    • /
    • pp.55-69
    • /
    • 1993
  • The purpose of this study is investigation on prevalence and clinical characteristics of headache among 10-39 years men and women. Information could be obtained with the questionnaire, and 1952 respondents completed the questionnaire. All participants were asked if they had experienced headache. Those responding positively were further questioned regarding the frequency, severity, character, location and duration of headache and were questioned regarding the experience of medical cunsultation and taking analgesics. The obtained results were as follows : 1. The life time prevalence of headache was 49.6% among men, 70.8% among women and 61.5% in all. 2. The prevalence of episodic tension type headache, chronic tension type headache, migraine, mixed type headache in this population was 27.1%, 5.0%, 2.8%, 23.1% respectively. 3. Headache duration was classified as less than 1 hour, 1-6 hours, 6012 hours, more than 12 hours for 1 day. The percentage of each other case is 41.8%, 46.2%, 7.4% and 4.4% of headache suffers respectively. 4. As regards the severity of headache, 4.2% of headache suffers had a very mild pain intensity, 17.9% a mild pain, 57.7% a moderate pain, 18.1% a severe pain and 2.2% a quite severe pain. 5. Headache occured at morning in 8.2% of headache suffers, at afternoon in 9.4%, at evening in 18.1%, at night in 4.3% and at anytime in 59.9%. 6. 11.7% of headache suffers among men consulted doctor, 13.9% among women and 13.1% in all. 7. 66.2% of headache suffers didnt have any analgesics because of their pain, 33.8% of headache suffers had analgesics because of their pain.

  • PDF