• Title/Summary/Keyword: aged wood

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Fundamental Investigation of Functional Property of Concrete Mixed with Functional Materials

  • Lee, Jong-Chan;Lee, Moon-Hwan;Lee, Sae-Hyun;Park, Young-Sin;Park, Jae-Myung
    • International Journal of Concrete Structures and Materials
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    • v.18 no.3E
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    • pp.165-171
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    • 2006
  • Environment-friendly materials are increasingly used as building construction materials nowadays, and the market share of those is growing. Accordingly, the research and developments in terms of environmental value are progressing steadily now. The main characteristics of environmental products are far-infrared radiation, negative-ion emission, electromagnetic wave shielding, and antimicrobial property. These products are often used in mortar and as spray on the finishing material. Nevertheless, there are hardly any research on the functional properties of concrete, the main material in construction field. Thus, we evaluated such basic properties of concrete as slump, compressive strength and air content while using such functional materials as sericite, wood-pattern sandstone, carbon black and nano-metric silver solution to focus on their functional properties like far-infrared radiation, negative ion emission, electro magnetic wave shielding, and antimicrobial activity in this research. The results indicated that the most useful material in the functional materials was carbon black. Sericite and nano-metric silver solution had a little effect on the functional property. Moreover, although wood-pattern sandstone had very high functional property, it exhibited too low compressive strength to be applied, to concrete as a factory product. Antimicrobial property of nano-metric silver solution in the concrete was not clear demonstrated, but if these specimens were to be aged in $CO_2$ gas for a long time, it might be apparent.

The Depression in Middle-aged Women in Kwangwondo (일부지역 중년여성의 우울 정도와 영향 요인에 관한 연구)

  • Lee, Kyu-Eun;Choi, Euy-Soon
    • Women's Health Nursing
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    • v.5 no.3
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    • pp.299-312
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    • 1999
  • The purpose of this study was to analyze the depression in middle-aged women. The subjects for this study were 246 middle-aged women in Kangwondo, the northeastern part of Korea. Data were collected from February 22 to April 24, 1999 by a structured questionnaire. The instruments for this study were CES-D (Radloff, 1977), somatic discomfort scale (Wittenborn, 1979), self-esteem scale (Rosenburg, 1971) and life satisfaction Index-Z (Wood et al. 1969). The data were analyzed by SAS/PC+ program using ANOVA, Pearson Correlation Coefficient. The results of the study were as follows : 1. Of 246 middle-aged women, 91 women (37%) revealed depression. The percentage of mild, moderate, severe depression were 17.78%, 11.28%, 7.72% respectively. 2. The statistically significant difference in the score of the depression according to the age (F=3.46, p=.0001)was obtained. 3. There were significant differences between depression and somatic discomfort (F=15.71, p=.0001). 4. The significant differences between depression and life satisfaction (F=23.89, p=.0001) was obtained. 5. The data shows the positive correlations between depression and somatic discomfort (r=.4856, p=.0001), between self-esteem and life-satisfaction(r=.2727, p=.0001), but we found negative correlations between depression and self-esteem(r=-4200, p=.0001), between depression and life-satisfaction(r=-.4409, p=.0001), between somatic discomfort and self-esteem(r=-.2275, p=.0015), between somatic discomfort and life-satisfaction(r=-.2695, p=.0002).

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Source Identification and Estimation of Source Apportionment of Ambient PM2.5 at Western National Park Site in USA (미국 서부 국립공원 지역의 미국 서부 국립공원 지역의 PM2.5에 대한 오염원 확인 및 기여도 추정)

  • Hwang, In-Jo
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.1
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    • pp.21-33
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    • 2010
  • The objective of this study was to estimate the $PM_{2.5}$ source apportionment at the Pinnacles National Monument IMPROVE site in western coastal USA. The PMF was applied to identify the existing sources and apportion the $PM_{2.5}$ mass to each source. To analyze local source impacts from various wind directions, the NPR analysis was performed using source contribution results with the wind direction values measured at the site. Also, PSCF was applied to identify the locations by point sources relative to the back trajectories. A total of 1,634 samples were collected from March 1988 to May 2004 by IMPROVE sampler and 32 chemical species were analyzed by PIXE, PESA, XRF, IC, and TOR methods. The PMF modeling identified seven sources and the average mass was apportioned to gasoline vehicle, secondary sulfate, aged sea salt, secondary nitrate, wood/field burning, diesel emission, and soil, respectively. In this study, the average mass was apportioned to gasoline vehicle (33.0%), secondary sulfate (25.7%), aged sea salt (17.8%), and secondary nitrate (10.1%). Also, this study suggests the possible role for source apportionment study of $PM_{2.5}$ at similar areas such as wildness, national park, and coastal areas in Korea.

The Evaluation of Thermal Aging Characteristics in Insulating Paper for the Use of the Pole Transformers (가속열화 방법에 의한 주상변압기 절연물의 열열화 특성 평가)

  • Lee, Byung-Sung;Song, Il-Keun;Lee, Jae-Bong;Park, Dong-Bae;Han, Sang-Ok
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07a
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    • pp.100-103
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    • 2003
  • The primary insulation system used in an oil-filled transformer is kraft paper, wood, porcelain and oil. Modern transformers use paper that is chemically treated to improve its tensile strength properties and resistance to aging caused by immersion in oil. But these insulation papers are mainly aged to thermal stress. Over the course of the insulation paper and oil's life it is exposed to high temperatures, oxygen and water. Its interaction with the steel of the tank and core plus the copper and aluminium of the windings will eventually cause the chemical properties of the oil to decay. High temperature have an effect on mechanical strength of cellulous paper using the layer insulation. We made two aging cell in which thermal aging tests of insulation papers and mineral oil are conducted. It is measured dielectric strength, number of acid, moisture, etc. of insulation paper and oil aged in the aging cells.

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Elderly Preference of Interior Design in Residential Space (주거공간의 실내디자인 특성에 대한 노인선호)

  • Lee, Chun-Yeop;Oh, Chan-Ohk
    • Journal of the Korean housing association
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    • v.20 no.6
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    • pp.67-76
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    • 2009
  • As the needs of housing for the elderly has increased, many researches have been carried out and some housing projects for the elderly including nursing home began to be provided. Most researches have focused on the development of housing type or space layout and only several ones on interior design. The interior design in house influences physically or psychologically on the elderly who lives in. Also, the subject of them which examined the needs or preference for housing for the elderly were the middle-aged, not the aged. The purpose of the study was to examine the preferred characteristics of interior design in residential space by the elderly. The structured interview with 120 old persons who lived in Busan was carried out using by a questionnaire and 3D images. The elderly answered about the preferred interior style, color, lighting and interior finishes of each room in house, such as living room, master bedroom, kitchen, and bathroom. On the basis of the findings, the characteristics of interior design of each room in house which the elderly preferred were presented. In general, they preferred the mixed interior style with tradition and modem. Also, the reddish and purple interior color, flower or plant patterned wall finishes, and wood floor were preferred in living room and master bedroom by the elderly. The white interior color and one colored wall finishes without any pattern were preferred in kitchen and bathroom.

Morus Nigra Extract Attenuates Cognition Impairment and GABAergic Interneuron Degeneration in Aged Rat Brain

  • Lee, Joo Hee;Kim, Yoonju;Song, Min Kyung;Kim, Youn-Jung
    • Journal of Korean Biological Nursing Science
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    • v.24 no.2
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    • pp.77-85
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    • 2022
  • Purpose: Aging process comes with cognitive impairment due to decreased neuronal cell number, activity, and neuronal circuit. Alteration of inhibitory neurons contributes to cognitive impairment in normal aging and is responsible for disrupting the excitation/inhibition balance by reducing the synthesis of gamma-aminobutyric acid (GABA). Morus nigra (Mulberry) is a natural physiologically active substance that has been proven to have anti-oxidant, anti-diabetic, and anti-inflammatory effects through many studies. This study aimed to evaluate the effects of the mulberry extract (ME) on cognitive function through anti-oxidant enzyme and GABAergic neuronal activity in aged rat brain. Methods: Sprague Dawley rats were randomly assigned as the young group (8 weeks, n= 8), aging group (67 weeks, n= 8), and aging+ mulberry extract group (67 weeks, n= 8). The aging+ mulberry extract group was orally administered 500 mg/kg/d mulberry extract for 6 weeks. Results: The aging+ mulberry extract group improved spatial and short-term memory. The antioxidant potential of ME increased the expression of superoxide dismutase-1 (SOD-1) and decreased inducible nitric oxide synthase (iNOS). Also, the aging+ mulberry extract group significantly increased the expression of GABAergic interneuron in hippocampus cornu ammonis1 (CA1) compared to the aging group. Conclusion: The number of GABAergic inhibitory interneurons was deceased and memory functions in the aging process, but those symptoms were improved and restored by mulberry extract administration.

Development of a Stand Density Management Diagram for Teak Forests in Southern India

  • Tewari, Vindhya Prasad;Alvarez-Gonz, Juan Gabriel
    • Journal of Forest and Environmental Science
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    • v.30 no.3
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    • pp.259-266
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    • 2014
  • Stand Density Diagrams (SDD) are average stand-level models which graphically illustrate the relationship between yield, density and mortality throughout the various stages of forest development. These are useful tools for designing, displaying and evaluating alternative density regimes in even-aged forest ecosystems to achieve a desired future condition. This contribution presents an example of a SDD that has been constructed for teak forests of Karnataka in southern India. The relationship between stand density, dominant height, quadratic mean diameter, relative spacing and stand volume is represented in one graph. The relative spacing index was used to characterize the population density. Two equations were fitted simultaneously to the data collected from 27 sample plots measured annually for three years: one relates quadratic mean diameter with stand density and dominant height while the other relates total stand volume with quadratic mean diameter, stand density and dominant height.

Anatomical Studies on Tumorous Tissue Formed in a Stem of Ailanthus altissima Swingle by Artificial Banding and Its Subsequent Removing Treatment -Characters of Individual Elements- (인위적(人爲的)인 밴드결체(結締) 및 해체처리(解締處理)로 형성(形成)된 가죽나무(Ailanthus altissima Swingle) 수간(樹幹)의 종양조직(腫瘍組織)에 관한 해부학적(解剖學的) 연구(硏究) -조직(組織) 구성세포(構成細胞)의 특성(特性)-)

  • Eom, Young Geun;Lee, Phil Woo
    • Journal of Korean Society of Forest Science
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    • v.78 no.3
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    • pp.287-301
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    • 1989
  • A tree of Ailanthus altissima Swingle was fastened with a plastic band, 19mm wide, around the stem 180cm above ground level and was left to grow under this condition for one year, By removal of this band the tumorous tissue gradually developed and the tree bearing distinct tumorous tissue, an overgrowth surrounding the stem, was harvested two years after the band removal. For the investigation of this tumorous part and its comparison with adjacent normal parts in the anatomical features of individual elements, the tumorous part and parts directly and 40cm above and below the tumorous part were obtained from the tree. The tumor wood having remarkably wider growth increment occurred in the 3rd growth ring the first year after removal of the fastened band, and the barrier zone which delimited the discolored wood from the normal-colored wood inwards appeared u1 the intra-2nd growth ring produced during the fastened period in the tumorous part and the false ring-like zones equivalent to barrier Zone were shown in the normal-colored 2nd growth rings of the parts directly and 40cm above and below the tumorous part, as well. The tumor wood, the 3rd growth ring, and proportion of the 2nd growth ring formed after barrier zone in the tumorous part shared common characteristics in the irregular growth ring boundary, misshapen and shorter individual fibers and vessel elements, and large ray widths and heights. The springwood pores were smaller in diameter in the tumor wood, and the larger radial and smaller tangential diameters of summerwood solitary pores and individual pores consisting of pore multiples in proportion of the 2nd growth ring formed after the barrier zone were transformed into near-isodiametric in the tumor wood, the 3rd growth ring, in the tumorous part. Only in proportion of the 2nd growth ring formed after the barrier zone were transformed into near-isodiametric in the tumor wood, the 3rd growth ring, in the tumorous part, ray densities greatly increased. And the massive tumor wood was caused not by cell size but by cell number because the radial and tangential diameters of fibers in the tumor wood, the 3rd growth ring, in the tumorous part were not sufficiently different from those in the same aged growth rings of the directly and 40cm above and below the tumorous part.

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Effect of Medium Composition Including Chestnut Woodchips and Granular Rockwool on Growth of Plug Seedlings (밤나무 목재입자와 입상 암면의 배지내 혼합 비율이 플러그묘의 생육에 미치는 영향)

  • Lim, Mi Young;Jeong, Byoung Ryong
    • Horticultural Science & Technology
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    • v.18 no.4
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    • pp.508-512
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    • 2000
  • Growth of red pepper (Capsicum annuum) 'Kumtap', tomato (Lycoperisocon esculentum) 'Seokwang', petunia (Petunia hybrida) 'Madness Rose', and pansy (Viola tricolor) 'Magestic Giant' in mixtures of chestnut woodchips and granular rockwool at 25:75, 50:50, or 75:25 (v/v) was examined. Chestnut woodchips were soaked in water for 48 hours or aged in open field for 6 months in order to remove substances impeding plant growth. A commercial plug medium was used as the control. All treatments showed in a similar result in red pepper, petunia, and pansy. Plant height, fresh weight, dry weight, and chlorophyll content in media containing chestnut woodchips, especially in higher proportions, were poorer as compared to those in the control. On the contrary, height, fresh weight, and dry weight of tomato seedlings in media containing woodchips were significantly higher than those in the control. For petunia, pansy, and red pepper, six month ageing in open field of woodchips was more favorable for growth than 48 hour water soaking. Emergance of petunia seed was inferior, especially when woodchip content was higher, to the other crops with a resultant growth suppression. From the results, chestnut woodchips proved to be a practical material as a medium component only in tomato plants.

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The Characteristics and Needs of Computer Furniture for the Adolescent (청소년 컴퓨터용 가구특성과 요구에 관한 연구)

  • Pak, Hee-Jin
    • Journal of the Korean housing association
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    • v.19 no.4
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    • pp.1-10
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    • 2008
  • According to the Korean National Statistics Office(KNSO), more than 90% of Korean adolescents aged from 15 to 19 use a computer for more than 10 hours per week. The KNSO also reveals that this age group mostly uses a computer in their own room, followed by a commercial place. It is also found that the house for the adolescent is not simply a physical environment, but is rather a center of their personal lives where their personal and social developments are formed. Therefore, the physical environment where computers are used is very important. The purpose of this study was to investigate the characteristics and needs of computer furniture for the adolescent. Data were collected through self-administered questionnaires and 414 adolescents participated. The results of this study are as follows: (1) Most of the respondents(42%) used the internet for less than one hour per day and it was used for community visits and operations, game, and chat rooms. (2) The desks where computers were used were specially designed and made of wood. Chairs were typically height adjustable with armrests and there was no task lighting for computer use. (3) The preferences of computer furniture were chairs with a high back, casters and armrests. The overall satisfaction of individual computer rooms was low. However, it is important for an adolescent to be provided with a user friendly environment for sound growth and development. Further study is therefore needed regarding environmental variables through empirical study.