• 제목/요약/키워드: board

검색결과 8,009건 처리시간 0.056초

Study on Press-drying of Italian Poplar Board and its Effect on Improvement of Wood Property (이태리포푸라재(材)의 건조성(乾燥性) 및 성질개선(性質改善)에 관(關)한 연구(硏究))

  • Jung, Hee Suk
    • Journal of Korean Society of Forest Science
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    • 제37권1호
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    • pp.17-30
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    • 1978
  • Press drying was used on italian poplar (Populus euamericana) to find the profitable means of drying. This study was designed to investigate the process of platen drying considering core temperature, drying time, current moisture content, drying rate, shrinkage and recovery, and green volume specific gravity, equilibrium moisture content and dimensional stability of press dried material and air dried material, The drying tests were conducted using 1.5 centimeter thick material at platen temperature of $175^{\circ}C$. The results were summarized as follows. 1. Core temperature was divided into three stages of drying characterized by period initial heating, plateau temperature and rising core temperature. Plateau temperature was 114 to $119^{\circ}C$. 2. The following predicting equations of drying time(y) in different core temperatures were developed for initial thickness($x_1$), initial moisture content ($x_2$) and final moisture content ($x_3$) 3. The predicting equaltion of current moisture content(u) was log u=4.658-0.060t as funtion of drying time(t) and that of drying rate(r) was log r=-2.797-0.049t. Current moisture content and drying rate of air drying were shown in figure 2. 4. The predicting equation of shrinkage in thickness direction(y) was log y=1.933+0.038t as function of drying time(t), and that of expansion in width direction was $y=-0.692+0.043t-0.001t^2$. 5. Thickness shrinkage was increased more than proportional at to pressure increase. Width shrinkage and thickness recovery was greatest at 35psi. 6. Green volume specific gravity of press dried material was 25% greater than that of air dried material. But equilibrium moisture content of press dried material was less 24% than that of air dried material. Antishrinkage efficiency of press dried material were obtained 27.7%.

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Forecasting of Demand for Papers in Korea (한국(韓國)의 지류(紙類) 수요예측(需要豫測)에 관한 연구(硏究))

  • Chung, Il Yong;Chung, Young Gwan
    • Journal of Korean Society of Forest Science
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    • 제65권1호
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    • pp.80-91
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    • 1984
  • The purposes of this study are to analyze and forecast the domestic demand for papers by regression models with time-series data (1965-81). For the period of 1965-81, the real GNP of Korea grew at annual average increase rate of 8.8 percent. On the other hand, the domestic demand of papers grew at annual average increase rate of 17.9 percent in this period. Especially, the annual average increase rate for board-papers accounted to 25.8 percent. To analyze domestic demand for papers, GNP, per capita GNP, price findex of papers, production activity index of the major papers consuming industries and price index of substitutive goods were selected as independent variables. The expected values of domestic demand for papers were computed by forecasting equations as follows. T-values are in parentheses. ${\ell}nDDP=2.452+1.986{\ell}nPG-0.844{\ell}nPWI$ $(33.397)^*\;(-6.149)^*\;R^2=0.997$ ${\ell}nDDP=6.468+0.827{\ell}nPDA$ $(17.403)^*\;R^2=0.950$ DDP : Domestic demand for papers PG : Real GNP per capita (1,000 won) PWI : Real price index of papers (1980 = 100) PDAV : Production activity index of the major papers consuming industries The results analyzed and forecasted by these models are summarized as follows: The domestic demand for papers had positive correlation toward per capita GNP and production activity index of the major papers consuming industries. Per capita GNP elasticity of the domestic demand for papers was the most elastic among independent variables. The price elasticity of domestic demand for papers had negative sign and inelastic. These were not only statistically significant but theoretically compatible. The domestic demand for papers was projected to be 3,152-4,470 thousand mit in 1991, representing at annual increase rate of 5.0-12.4 percent during the period of 1982-91. Domestic demand for papers per capita was projected to be 69.1-98.0 kg in 1991.

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Research on Methods of Developing Quadrangular Culm of Bamboos (사각죽조성(四角竹造成)에 관(關)한 연구(硏究))

  • Chong, Hyon-Pae
    • Journal of Korean Society of Forest Science
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    • 제10권1호
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    • pp.7-16
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    • 1970
  • There are 19 species of bamboo in Korea, among which few are of commercial value. The Phyllostachys has wide range of utilization, for sea weed production, industrial production of various bamboo wares, etc. The total export from Chenla-Namdo to some more than ten countries was recorded 204,000,000 won worth in 1969. As civilization develops so does the techniques of bamboo works, and they in turn accelerate the demand for bamboo wood of better quality. In the light of this trend, the author attempted to make bamboo plants to develope a quadragular culm with elaborate design as disired instead of the original round one, with the expectation that it might be widely welcomed by hand workers, interior decorators. Here are some facts found out in this experiment: 1). The greater the diameter of the shoot at the eye level was, the better result was brought, and as shown in Fig. 5 the rate of success was 72% with the shoots of 7.5 cm thick. 2). The shoots of 30 cm in length showed 100% of success, developing into a desired quadrangular culms without fail(See Fig. 6). 3). The intensity of wood fiber increased as time lapsed, without receiving any influence by the weather (See Fig. 7, 8). 4). During the growing, the culm proved to be flexible enough to bend up to 90 degree (See Fig. 9). 5). In an attempt to promote the value of bamboo by decoration, the author tried to impress rectangular indents on the culm. The indention using a qudangular board 1cm smaller in width than the shoot diameter gave 100% success (See Fig. 10). 6). Design experiment was also successful both in coloration and impressing and the resulting designs delicately depended on the kinds of chemicals used and their combination (Table 2) (See Fig. 12, 13, 14). With the above mentioned findings, the author concludes that the mass production of quadrangular bamboo culm is quite a promissing as an new industry to develope bamboo works to a more valuable one. This research was carried out with the research fund provided by the Ministry of Education in 1969.

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Dietitians' Perception of Importance about Standards of Foodservice Management Associated with Long-Term Care Hospital Accreditation (요양병원 인증제 관련 급식관리 기준에 대한 영양사들의 중요성 인식도)

  • Lee, Joo-eun
    • Journal of the Korean Society of Food Science and Nutrition
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    • 제44권10호
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    • pp.1558-1566
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    • 2015
  • The purpose of this study was to examine dietitians' perception of importance about standards of foodservice management associated with long-term care hospital accreditation. This study was carried out through a postal survey consisting of 500 questionnaires, and 157 returned questionnaires were used in the statistical analysis. The results were summarized as follows. Average scores of perception of importance were 4.54/5 points in foodservice production management domain, 4.56/5 points in foodservice facilities management domain, and 4.70/5 points in foodservice sanitation domain. The average scores of importance of long-term care hospitals without accreditation were significantly (P<0.05) lower than those of hospitals with accreditation in items of 'establishment of ventilation equipment in kitchen', 'establishment of hand-washstand in toilet (warm-water, soap)', 'setup of sterilizing foothold in entrance of kitchen and toilet', 'division and use of knife, chopping board, gloves, and utensils before and after cook', 'establishment of cleaning plan and cyclic practice', and 'recording of receiving diary'. Results indicate that there is a need to supplement a casebook of regulations by suggesting detailed and critical limits in the case of below average points of importance. A manual, including HACCP standards for foodservice management of long-term care hospitals, is needed, along with education and webpage for comparing notes on accreditation of long-term care hospitals.

Cognitive and Psychological Characteristics of Psychiatric Patients with Military Service Eligibility Issues (군 복무 적합성 판정을 위해 내원한 환자들의 인지적 및 심리적 특성)

  • Nam, Jisoo;Choi, Junho;Kim, Eunkyeong
    • Korean Journal of Psychosomatic Medicine
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    • 제27권2호
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    • pp.119-129
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    • 2019
  • Objectives : The purpose of this study was to examine cognitive and psychological characteristics of patients who visited psychiatric outpatient clinic with military service suitability issues. Methods : Since January, 2017 to September, 2018, patients were recruited from the department of psychiatry of university hospital. Participants were diagnosed using DSM-5 criteria by board certified psychiatrists. And each of participants tested with K-WAIS-IV, K-SCL-95 by clinical psychologist. The data were analyzed using SPSS 18.0. Results : The results indicated 24.6% of the patients have significantly low level of intellectual functioning. and 10.8% of the patients have borderline level of intellectual functioning, and 26.3% of them were below average. The results of psychological characteristics showed patients have cautious and potentially dangerous level of depression, anxiety, agoraphobia, and suicidal idea. And PTSD subscale's mean score was above problematic level. Next, we divided patients into two groups based on question of whether the patient is eligible to serve in the military service or not arises from recruitment process or army training center. But two group didn't differ significantly. And for further analyses, we also divided patients into two groups based on if they got single psychiatric diagnosis or more than one psychiatric diagnosis. Conclusions : The results indicated that group which has coexisting psychiatric disorders were more depressed, had higher level of anger and aggression, and had more serious levels of suicidal ideas than single psychiatric diagnosis group. The implications and limitations were discussed along with some suggestions for the future studies.

Regeneration Processes of Nutrients in the Polar Front Area of the East Sea 1. Relationships between Water Mass and Nutrient Distribution Pattern in Autumn (동해 극전선역의 영양염류 순환과정 1. 추계 수괴와 영양염 분포와의 관계)

  • Moon Chang-Ho;YANG Han-Soeb;LEE Kwang Woo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • 제29권4호
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    • pp.503-526
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    • 1996
  • A synoptic survery of chemical characteristics in the last Sea of Korea was carried out at the 11 stations near Ullungdo in November, 1994 on board R/V Tam-Yang. On the basis of the vortical distribution patterns of temperature, salinity and dissolved oxygen, water masses in the study area are divided into five groups; 1) Tsushima Surface Water (TSW), 2) Tsushima Middle Water (TMW), 3) East Sea Intermediate Water (ESIW), 4) last Sea Proper Water (ESPW), 5) Mixed Water (MW). In the vertical profiles of nutrients, the concentrations were very low in the surface layer and increased rapidly near the thermocline. There was a slight decrease in the ESIW and the concentrations were constant with the depth below 300m except dissolved silicate which still increased with depth. Relatively high value of Si/P ratio (25.2) in ESPW, whick is the oldest water mass, suggests that Si is regenerating more slowly compared to other nutrients. The relatively high value of N/P ratio (18.6) in the surface layer might be related to high vertical eddy diffusivity $(K_z)$ of $1.19\;cm^{2}/sec$ and high nitrate upward flux of $103.7\;{\mu}g-at/m^{2}/hr$, compared to the values reported in other areas. Apparent Oxygen Utilization (AOU) was very low in the surface layer and increased in the TMW, but there was a slight decrease in the ESIW. The highest value of AOU occurred in the ESPW. The slpoe of P/AOU was 0.50. The study on the relationship between water masses and nutrient distribution patterns is important in understanding the regeneration processes of nutrients in the polar region of the last Sea.

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An analysis of the Domestic Interior Materials as the Ecological Design Aspects (친환경측면에서 본 국내 실내건축자재의 현황 조사 및 분석)

  • Chun Jin-Hie;Kim Jung-Ah
    • Archives of design research
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    • 제19권4호
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    • pp.133-144
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    • 2006
  • According to the latest report by the Customer Protection Board, those who moved into newly constructed buildings are complaining about unidentified pains, asking for more careful selection of constructive materials for prevention of such potential problems. It is internationally recognized today that ecological materials can serve a significant factor for users' health, environmental protection and better industrial competitiveness. This study examined eco-design aspects of each interior material through web site search, in order to help customers learn about and capitalize on eco materials in a proper manner. As a result, 1. It turned out that the domestic industry are giving an impetus to releasing new eco items focusing on lower VOCs emission or addition of functional components as part of the marketing strategy. However, it is recommended that company understand significance of life cycle, and produce eco-concept materials. 2. The reliable standard for choosing the domestic material is EL, HB, GR marks. It is desirable to enhance recycling technologies and expand the sustainable consumption. customer class, since many recycled items are not developed. 3. The sourcing is a vulnerable part in terms of the concept of being environment-friendly material. Therefore, many manufacturers should design the easy knock-down products and produce the good items using recycled materials instead of new raw materials. Also solutions for making the energy from burning material should be studied. 4. The guidebook or manual with correct information about eco-materials is required to promote production and consumption with sustainable concept. 5. Many manufacturers are emphasizing ecological materials for customers, but some of them intended to disrupt customers' proper selection by promoting even unverified items to be environment-friendly.

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Relationship Between Carotid Intima-Media Thickness Using Ultrasonography and Diagnostic Indices of Metabolic Syndrome (초음파를 이용한 경동맥 내-중막 두께와 대사증후군 진단지표의 연관성)

  • Ko, Kyung-Sun;Heo, Kyung-Hwa;Won, Yong-Lim;Lee, Sung-Kook;Kim, Ki-Woong
    • Journal of radiological science and technology
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    • 제32권3호
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    • pp.285-291
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    • 2009
  • The aim of the present study was undertaken to investigate the association between diagnostic indices of metabolic syndrome(MetS) with carotid intima-media thickness using ultrasonography. The participants in the study were 315 male employees without carotid atherosclerosis and other cardiovascular disease. This study was approved by the Institutional Review Board of Occupational Safety and Health Research Institute. Written informed consent for the participants in this study was obtained from all individuals. Anthropometric parameters and biochemical characteristics were done using each specific equipments and the NCEP-ATP III criteria were used to define MetS. They were examined by B-mode ultrasound to measure the carotid intima-media thickness(carotid IMT) at the near and far walls of common carotid and bifurcation(bulb). The mean carotid IMT was $0.739{\pm}0.137\;mm$ and it's thickness significantly increased with the increase in age. Also, amounts of systolic and diastolic blood pressure, triglyceride and fasting glucose were significantly increased with the increase in age. Carotid IMT were significantly correlated with BMI(r=0.170, p=0.004), systolic(r=0.148, p=0.011) and diastolic blood pressure(r=0.123, p=0.036) and HDL-cholesterol(r=-0.164, p=0.005). On multiple logistic regression analysis for the diagnostic indices of MetS, carotid IMT were significantly associated with blood pressure(OR=4.220, p<0.01) and MetS(OR=1.301, p<0.05). The results indicate that blood pressure and MetS are important risk factors for carotid atherosclerosis.

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Development and Performance Test of Preamplifier and Amplifier for Gamma Probe (감마프로브용 전단증폭기와 주증폭기의 개발과 성능 평가)

  • Bong, Jung-Kyun;Kim, Hee-Joung;Lee, Jong-Doo;Kwon, Soo-Il
    • The Korean Journal of Nuclear Medicine
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    • 제33권1호
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    • pp.100-109
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    • 1999
  • Purpose: Preamplifier and amplifier are very important parts for developing a portable counting or imaging gamma probe. They can be used for analyzing pulses containing energy and position information for the emitted radiations. The commercial Nuclear Instrument Modules (NIMs) can be used for processing these pulses. However, it may be improper to use NIMs in developing a portable gamma probe, because of its size and high price. The purpose of this study was to develop both preamplifier and amplifier and measure their performance characteristics. Materials and Methods: The preamplifier and amplifier were designed as a charge sensitive device and a capacitor resistor-resistor capacitor (CR-RC) electronic circuit, respectively, and they were mounted on a print circuit board (PCB). We acquired and analyzed energy spectra for Tc-99m and Cs-137 using both PCB and NIMs. Multichannel analyzer (Accuspec/A, Canberra Industries Inc., Meriden Connecticut, U.S.A) and scintillation detectors (EP-047(Bicron Saint-Gobain/Norton Industrial EP-047 (Ceramics Co., Ohio, U.S.A) with $2"{\times}2"$ NaI(T1) crystal and R1535 (Hamamatsu Photonics K.K., Electron Tube Center, Shizuoka-ken, Japan) with $1"{\times}1"$ NaI(T1) crystal were used for acquiring the energy spectra. Results: Using PCB, energy resolutions of EP-047 detectors for Tc-99m and Cs-137 were 12.92% and 5.01%, respectively, whereas R1535 showed 13.75% and 5.19% of energy resolution. Using the NIM devices, energy resolutions of EP-047 detector for Tc-99m and Cs-137 were measured as 14.6% and 7.58%, respectively. However, reliable energy spectrum of R1535 detector could not be acquired, since its photomultiplier tube (PMT) requires a specific type of preamplifier. Conclusion: We developed a special preamplifier and amplifier suitable for a small sized gamma probe that showed good energy resolutions independent of PMT types. The results indicate that the PCB can be used in developing both counting and imaging gamma probe.

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Treatment Level of a Pond System for Ecological Treatment and Recycling of Animal Excreta (생태적 축산폐수 처리 및 재활용 연못시스템의 폐수처리수준)

  • Yang, Hong-Mo;Rhee, Chong-Ouk
    • Korean Journal of Environmental Agriculture
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    • 제17권1호
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    • pp.70-75
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    • 1998
  • A model of pond system is developed for treatment and recycling of excreta from twenty-five adult dairy cattle. It is composed of wastewater treatment ponds and small fish ponds. Those are three facultative ponds in series; primary-secondary-tertiary pond and these are designed to rear carps without feeding. A pit is constructed at the bottom of primary pond for efficient sludge sedimentation and effective methane fermentation. It is contrived to block into it the penetration of oxygen dissolved in the upper layer of pond water. The excreta from the cattle housed in stalls are diluted by water used for clearing them. The washed excreta flow into the pit. The average yearly $BOD_5$ concentration of influent is 398.7mg/l. That of the effluent from primary, secondary and tertiary pond of the system is 49.18, 27.9, and 19.8.mg/l respectively. Approximate 88, 93, and 95 % of BOD5 are removed in each pond. The mean yearly SS concentration of influent is 360.5 mg/l That of the effluent from each pond is 53.4, 45.7, and32.7mg/l respectively. Approximate 86, 88, and 91% of SS are removed in each pond. The $BOD_5$ concentration of secondary and tertiary pond can satisfy 30mg/l secondary treatment standard. The SS concentration of effluent from tertiary pond, however, is slightly greater than the standard, which results from activities of carps growing in the pond. The average yearly total nitrogen concentration of influent is 206.8mg/l and that of the effluent from each pond is 48.6, 30.8, and 21.0mg/l respectively. Approximate 74, 88, and 90% of total nitrogen are removed in each pond. The mean yearly total phosphorous concentration of influent is 20.7mg/l and that of the effluent from each pond is 5.3, 3.2, and 2.1mg/l respectively. Approximate 97, 98, and 99% of total phosphorous are removed in each pond. The high removal of nitrogen and phosphorous results from active growth of algae in the upper layer of pond water. Important pond design parameters for southern part of Korea -- areal loading of BOD5, liquid depth, hydraulic detention time, free board, and pond arrangement -- are taken up.

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