• Title/Summary/Keyword: strength index

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Thermal and Mechanical Properties of Flame Retardant ABS Nanocomposites Containing Organo-Modified Layered Double Hydoxide (유기변성 LDH를 사용한 난연 ABS 나노복합재료의 열적 및 기계적 물성)

  • Kim, Seog-Jun
    • Elastomers and Composites
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    • v.43 no.4
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    • pp.241-252
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    • 2008
  • ZnAl-LDH(layered double hydroxide) modified with oleic acid(SO-ZnAl LDH) was synthesized and added to the flame retardant ABS compounds containing brominated epoxy resin(BER) and antimony trioxide(${Sb_2}{O_3}$). Flame retardant ABS compounds were manufactured by using a twin-screw co-rotating extruder and subsequently injection molded into several specimen for flame retardancy and mechanical properties. The XRD patterns of ABS nanocomposites showed no peaks. The thermal stability of ABS nanocomposites was enhanced by the addition of SO-ZnAl LDH as shown in TGA results. However, these nanocomposites showed no rating in the UL 94 vertical test at 1.6 mm thickness. Only ABS nanocomposites with additional BER more than 1.5 wt% showed UL 94 V0 rating. Notched Izod impact strength, tensile modulus, and elongation at break of flame retardant ABS nanocomposites increased with the proportion of So-ZnAl LDH whereas their melt index decreased.

Effect of Sowing Rates on Growth and Yield t Furrow Sowing of Rice in Paddy Field (벼 무논골뿌림재배시 파종량이 생육 및 수량에 미치는 영향)

  • 송영주;고복래;황창주;박건호
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.1
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    • pp.86-91
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    • 1995
  • This experiment was conducted to understand the response on sowing rates at furrow sowing of rice in paddy field. As sowing rates was increased, the number of seedling stand per$m^2$ was icreased, while panicie number per plant was decreased slightly. Leaf area at heading stage and effective tiller ratio were decreased with increasing of sowing rates, but heading date was not defferent among sowing rates. According to sowing rates was increased, culm length, panicle length, breaking strength, culm diameter were decreased, while lodging index was increased. Also, field lodging was observed in the higer sowing rates over 5kg/l0a. Althougth the panicle number per $m^2$ was increased with increasing of sowing rates, spike let per panicle and percent of filled spikelet were decreased. According to the result from the path coefficient analysis, percent of filled spikelets well identified to be the most influential variables on the variability in rice yield, so that improving percent of filled spikelets by inhibition of field lodging was the important matter to increase the yield. The optimal sowing rate and the number of seedling stand were estimated to be 4.5kg/l0a and 105 per $m^2$ respectively.

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Electrical Properties of Laser CVD Silicon Nitride Film (Laser CVD SiN막의 전기적 특성)

  • Kim, Yong-Woo;Kim, Sang-Wook;Park, Jong-Wook;Kim, Chun-Sub;Sung, Yung-Kwon
    • Proceedings of the KIEE Conference
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    • 1990.11a
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    • pp.85-87
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    • 1990
  • Silicon nitride film was deposited on a silicon wafer using a laser CVD(LCVD) technique, which is based on direct photolysis of $SiH_4/NH_3$ gas mixture by ArF laser beam(${\lambda}=193\;nm$). The refractive index of deposited SiN film is 1.9 at the temperature of $300^{\circ}C$, pressure of 5 torr. The breakdown field strength of LCVD SiN film was 10MV/cm. In IR spectrum, the absorption peak of Si-H, N-H, and Si-N is detected and it is shown that hydrogen is included in SiN film. From analysis of absorption band. it is calculated that density of Si-H, N-H bond is higher than $5{\times}10^{22}cm^{-3}$. LCVD MIS capacitor and PECVD MIS capacitor have injection-type hysteresis but it is known that hysteresis loss of LCVD MIS capacitor is smaller than that of PECVD MIS capacitor. It means that Interface state density of LCVD capacitor is smaller than that of PECVD capacitor. In addition, the flatband voltage($V_{FB}$) of LCVD is smaller than that of PECVD capacitor. And it means that fixed charged density($Q_{FIX}$) of LCVD capacitor is smaller than that of PECVD MIS capacitor.

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Effects of a 12-week Combined Exercise Training Program on the Body Composition, Physical Fitness Levels, and Metabolic Syndrome Profiles of Obese Women (12주간의 복합운동이 비만여성의 신체조성, 체력 및 대사증후군에 미치는 영향)

  • Ha, Chang-Ho;Ha, Sung;So, Wi-Young
    • Journal of Korean Public Health Nursing
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    • v.26 no.3
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    • pp.417-427
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    • 2012
  • Purpose: The purpose of this study was to examine the effect of a 12-week combined exercise training program on the body composition, physical fitness levels, and metabolic syndrome profiles of obese women. Methods: Twelve obese women were assigned to the combined exercise training program group. The women underwent training for 70-90 min/d, three times per week for a period of 12 weeks. Paired samples t-tests were performed using SPSS ver. 17.0 for analysis of the results. Results: The results of this study showed that body-composition parameters such as weight, fat-free mass, body fat mass, body-mass index, body fat, waist-hip ratio, basal metabolic rate, and intra-abdominal fat, physical fitness parameters such as muscle strength, muscle endurance, flexibility, and cardiac endurance, and metabolic syndrome biomarkers such as triglyceride levels, high-density lipoprotein cholesterol levels, glucose levels, systolic blood pressure, and waist circumference before participation the training program differed significantly from those after participation in the training program (p<0.05). However, diastolic blood pressure before participation in the training program did not differ significantly from that after participation in the training program (p>0.05). Conclusion: We concluded that a 12-week combined exercise training program could be a good exercise program for improvement of the body composition, physical fitness levels, and metabolic syndrome profiles of obese women.

The Converge Effects of Kaatsu Treatment on Body Compositions, Physical Fitness and Dynamic and Static Balance during Unmilled Rice Dumbbell Exercise in Older Women (현미덤벨 운동시 가압처치가 노인여성의 신체구성, 체력과 동적 및 정적평형성에 미치는 융합적 효과)

  • Byun, Jae-Chul
    • Journal of the Korea Convergence Society
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    • v.9 no.4
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    • pp.261-269
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    • 2018
  • The purpose of this study was to determined the converge effects of Kaatsu treatment on body compositions, physical fitness and dynamic and static balance during unmilled rice dumbbell exercise in older women. They are divided into three groups(Kaatsu treatment+exercise, n=12, non-Kaatsu treatment+exercise, n=11, Control, n=12). In this study, there were a no significant differences on body weight and lean body mass and body mass index between the group, but there was a significant differences on percent of body fat between the group(P<.001). There was a significant differences on left grip strength between the group, and significant differences on flexibility and agility after the unmilled rice dumbbell exercise training. There were a significant differences on the dynamic and static balance between the group after the unmilled rice dumbbell exercise training(respectively P<.001, P<.05).

Statistical characteristics of electron precipitation into the atmosphere

  • Park, Mi-Young;Lee, Dae-Young;Cho, Jung-Hee;Shin, Dae-Kyu;Lee, Eun-Hee
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.94.2-94.2
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    • 2013
  • We studied the precipitation of magnetospheric energetic electrons into the Earth's atmosphere during magnetic storm times using precipitating electron flux data from the MEPED on board the NOAA Polar Orbiting Environmental Satellites (POES) low.altitude satellite, NOAA-16. We identified a total of 84 storm events between 2001 and 2012 using SYM-H index. We have done a superposition of precipitating electron fluxes for each of three energy ranges (i.e., e1: > 30 keV, e2: > 100 keV, e3: > 300 keV) for the identified storm times. The results show that the fluxes start to increase before the main phase of storm for all energy ranges and reach a maximum level just before the time of SYM-H minimum value. The precipitation timescales are energy-dependent, being shorter for lower energy, ~4.67 hours for e1, ~7.93 hours for e2 and ~26.5 hours for e3. The precipitating fluxes decline during the recovery phase of the storms. We examined the L shell dependence of the precipitating electron flux during the main phase. We found that statistically the precipitation fluxes are dominantly seen at L of ~ 3-4 or higher. This L value roughly corresponds to the plasmapause location during the main phase. Thus the results imply that the electron precipitation mainly occurs outside of the plasmapause. In addition, we classified the storm events by their strength and examined the dependence of precipitation on storm intensity. We found that the electron precipitation occurs on a faster time scale and penetrate into inner L shell region for a stronger storm.

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Quality Characteristics of Bread added Monascus anka Powder (홍국 분말을 첨가한 식빵의 품질 특성)

  • 김도완;김용해
    • Culinary science and hospitality research
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    • v.9 no.1
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    • pp.39-50
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    • 2003
  • Effects of Monascus anka powder on the quality characteristics of bread were investigated. Monascus anka powder was added to wheat flour at concentrations of 0, 1.0, 3.0 and 5.0%, respectively. The dough yield tended to decrease by adding Monascus anka products but those were not significant difference. The loaf volume index decreased by adding Monascus anka powder. The springiness of bread increased by the addition of Monascus anka. However bread with Monascus anka powder showed higher textural properties(strength, hardness, gumminess and brittleness) except for cohesi- veness than bread without Monascus anka powder. Color of L values decreased while a and b value increased with increasing quality of bread product No significant difference in pleasant flavor between bread with and without Monascus anka products were observed. However, bread with 1% Monascus anka powder showed the highest score for pleasant color, taste, texture and overall quality.

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Nitrogen level in tillage and no-tillage systems in Direct-seeded rice (경운과 무경운 조건에서 벼 건답휴립직파재배의 질소시비량)

  • 이석순;홍승범;백준호
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.36 no.2
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    • pp.160-165
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    • 1991
  • Growth performance of dry seeded paddy rice was studied at four N levels (10, 15, 20, and 25 kg/l0a) in tillage and no-tillage systems. Althougth the number of seedlings and maximum tillers tended to be higher and heading date was delayed by 2 days in tillage compared with those in no-tillage system, grainyield, yield components, lodging related characteristics, and N uptake were similar between two tillage ,systems. As N level increased, grain yield increased due to increased panicle number althougth the number of spikelets per panicle and percent ripended grains were similar and I, 000 grain weight decreased slightly. {Lodging index increased with increased N level due to higher plant height and decreased breaking strength and (culm base weigth, but lodging was not occurred in the field. Cellulose, hemicellulose, and lignin contents of culm base were similar among N levels. Concentration and uptake of N increased as N level increased.

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Comparison of Self-living Ability, Obesity Indices and Nutrient Intake according to Physical Fitness among the Elderly in Rural Areas (농촌 지역 일부 노인에서 신체 기능 정도에 따른 활동 제한도, 비만도 및 영양소 섭취 수준의 변화 양상 비교)

  • Suh, Hee-Jae;Kim, Bok-Hee
    • The Korean Journal of Food And Nutrition
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    • v.22 no.4
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    • pp.577-586
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    • 2009
  • Aging is associated with decreased energy expenditure, thermogenesis and energy requirements. Maintenance of physical fitness of the elderly has been reported to reduce the rate at which the basal metabolic rate, muscle strength, skeletal muscle mass and bone density deteriorate. Skeletal muscle disease is known to increase the risk of physical disability and psychological problems. This study was conducted to investigate changes in disability, emotional problems, body compositions, obesity indices and nutrient intake levels according to physical fitness with the elderly in rural areas. According to the results, physical fitness was negatively related with Activities of Daily Living(ADL, p<0.05), Instrumental Activities of Daily Living(IADL, p<0.001), Body Mass Index(BMI, p<0.001) and abdominal obesity(p<0.05), while it showed a positive correlation with the General Self Efficacy Scale(GSES)(p<0.001) and nutrient intake(p<0.05). When changes in these factors were compared according to the range of quartile of the Fullerton Advanced Balance Scale(FAB Scale), GSES(Q1=35.3, Q2=43.5, Q3=53.2, Q4=51.9, p<0.001), BMI(Q1=36.1%, Q2=34.7%, Q3=33.2%, Q4=28.6%, p<0.01), abdominal obesity(Q1=1.02, Q2=0.99, Q3=0.97, Q4=0.94, p<0.001) and nutrient intake(Q1=71.1%, Q2=75.4%, Q3=80.6%, Q4=80.2%, p<0.05) differed significantly. Taken together, these results suggested that better physical fitness would lead to a reduction in negative factors including physical disability and obesity indices, but to an increase in positive factors such as GSES and nutrient intake. The results of this study are expected to be used as basic data for the development of programs to promote the health of the elderly in a local society.

Measurement of Molecular Weights of Melamine-Urea-Formaldehyde Resins and Their Influences to Properties of Medium Density Fiberboards

  • Jeong, Bora;Park, Byung-Dae
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.6
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    • pp.913-922
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    • 2016
  • This study attempted to measure molecular weight (MW) of melamine-urea-formaldehyde (MUF) resins prepared by two different synthesis methods: the one-step MUF resins were synthesized in one batch procedure, while the two-step MUF resins were prepared by a physical mixing of urea-formaldehyde (UF) resin with melamine-formaldehyde (MF) resin that had been synthesized in a separate procedure. The properties of medium density fiberboard (MDF) panels bonded with two types of MUF resins were also investigated. MWs of these MUF resins were measured using gel permeation chromatography (GPC). In addition, this study measured the MWs of one-step MUF resin during its synthesis procedure. The performance of two types of MUF resins was evaluated by determining properties of MDF panels prepared in laboratory. As the synthesis procedure progressed, both number average MW ($M_n$) and weight average MW ($M_w$) of one-step MUF resin gradually increased, while the polydispersity index (PDI) decreased. And low Mw species of the resin predominantly decreased as the synthesis step progressed. The one-step MUF resin showed greater $M_n$ and $M_w$ than those of the two-step ones even though the PDI values of both resins were very similar each other. As expected, the one-step MUF resin resulted in better properties of MDF panels than those of two-step resins. In particular, the one-step MUF resin provided better internal bond (IB) strength and thickness swelling (TS) with MDF panels than those of two-step ones, indicating better water resistance of the one-step resin. These results suggest that the preparation method of MUF resins have a great impact on the MW and final panel properties.