• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.449-456
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• 2016

This study was aimed to quantify the amount of carbon dioxide emissions and to suggest suitable plans which consider the carbon emission reduction in the manufacturing process of the domestic structural glued laminated timber. Field investigation on two glued laminated timber manufacturers was conducted to find out material flow input values such as raw materials, transportation, manufacturing process, and energy consumption during manufacturing process. Based on the collected data and the relevant literatures about life cycle inventory (LCI), the amount of carbon dioxide emission per unit volume was quantified. Results show that the carbon dioxide emissions for sawing, drying and laminating process are 31.0, 109.0, 94.2 kg $CO_2eq./m^3$, respectively. These results show 13% lesser amount of total carbon dioxide emissions compared with the imported glued laminated timber in Korea. Furthermore, it was decreased about 37% when the fossil fuel would be replaced with biomass fuel in drying process. Findings from this study is effectively used as the basic data on the life cycle assessment of wooden building.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.205-213
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• 1996

본 연구에서는 남자대학생 80명을 대상으로 총 식이섬유 및 조섬유와 영양소 섭취상태를 비교 분석하였다. 남자대학생들의 평균 총 식이섬유 섭취량은 $20.54\pm5.82g으로$ 외국의 잠정적 권장량의 범위(20~30g)에는 들었으나 권장량의 하한치를 약간 상회하는데 그쳤다. 조섬유의 1일 평균 섭취량은 $8.43\pm5.56g으로$ 1일 식이섬유 섭취량의 약 41%에 해당하였으며 그 외 열량 및 다른 영양소의 평균 섭취량은 한국인 영양권장량과 비슷하거나 다소 더 높은 것으로 나타났다. 총 식이섬유 섭취량과 에너지 및 단백질, 당질, 그리고 조섬유의 섭취량 간에는 유의적인 상관관계를 보였으며, 당질이 가장 높은 상관계수(r=0.7232, p<0.001)를 보였다. 또한 조사 대학생들의 총 식이섬유 섭취량과 식품군별 섭취량과의 상관관계수를 보인 것은 채소류 (r=0.6548, p<0.001)였으며 그 다음은 곡류(0.5913, p<0.001)였으며 그 다음은 곡류(0.5913, p<0.001), 해조류(0.3300, p<0.01)였다. 조사 대학생들의 식이섬유 섭취량 중 총식이섬유 급원으로 가장 많이 섭취한 식품은 쌀과 김치였으며, 각각 총 식이섬유 섭취량의 11.98%와 7.64%에 기여하였다. 그 외 학생들이 많이 섭취한 라면, 고춧가루, 냉면, 빵, 콩나물, 밀가루, 깍두기, 무 등이 주요한 식이섬유 급원으로 나타났다. 본 연구의 남자대학생들의 식이섬유 섭취량은 외국의 잠정적 권장량의 범위(20~30g)에 속하였으나 충분한 양을 섭취하고 있는 것은 아니었으며, 오히려 경제수준의 향상으로 인한 식습관의 변화에 민감하게 반응하는 젊은 세대들인 조사대학생들의 장래 식이섬유 소비량은 더욱 감소할 것으로 추정된다. 그러므로 식이섬유 급원식품의 섭취를 증가시키는 방안이 모색될 필요가 있다. 따라서 성인기에 식이섬유 부족으로 나타나는 각종 질병의 위험을 예방하기 위해 정백비 위주의 식사를 지양하고 총 식이섬유 함량이 높은 해조류의 섭취를 널리 교육시키는 것이 바람직할 것으로 사료된다. 또한 보다 광범위하고 체계적인 대상자 선정을 통하여 식이섭취조사가 이루어져 식이섬유 섭취패턴을 연구할 필요가 있다.

• Journal of Nutrition and Health
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• v.38 no.10
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• pp.847-855
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• 2005

This study investigated and compared the daily activities and energy expenditure of normally-weighted and obese elementary school children. The participants were 115 boys and 115 girls (6th grade) at ten elementary schools in Busan. Time spent on each activity was evaluated using the twenty-four hour recall method. 1) The general characteristics of the normally-weighted and obese children did not differ, although the normally-weighted children exercised and used stairs more than the obese children.2) Among their classified activities, the children spent most of their time resting, study, leisure, physiology and hygiene, commuting, and housework in that decreasing order. Normally-weighted children spent less time tying down and in conversation with family and friends than obese ones. 3) The children's average activity factors were 1.47 - 1.50. The normally-weighted children's rest energy expenditure (REE) (1391.4 kcal,1264.7 kcal) was less than that of the obese children (1711.4 kcal. 1461.0 kcal) . The normally-weighted children's daily energy expenditure was less than that of the obese, but energy expenditure per body weight was less in obese children than in the normally-weighted. In conclusion, sedentary activities and energy expenditure per body weight was less in the obese compared to the normally-weighted children. Programs to help children perceive and practice desirable physical activities should be suggested for prevention of obesity in children. (Korean J Nutrition 38(10): 847$\sim$855,2005)

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.4
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• pp.76-89
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• 2014

In this paper, we propose a MAC(Media Access Control) protocol based on flexible RWT(RTS Waiting Time) for underwater mobile ad-hoc networks with a three-way handshaking mechanism. This protocol can solve a problem of collision between RTS(Request-To-Send) and CTS(Clear-To-Send) packets in existing MACA(Multiple Access with Collision Avoidance) protocol. This proposed MAC protocol is also an effective protocol which can apply to underwater mobile ad-hoc networks in a real field by using implementable technologies. We set flexible RTS Waiting Time called RWT, considering various characteristics of underwater environment. It is possible to support variable network size according to node mobility. Finally, we conduct a performance evaluation between proposed MAC protocol and existing MACA based MAC protocol through practical implementation and experiment. As a result, we verify the superiority of our proposed MAC protocol in terms of throughput, packet drop rate, average transmission time, energy consumption and channel utilization.

• Proceedings of the ESK Conference
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• 1997.10a
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• pp.35-39
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• 1997

스키는 겨울철에 하는 옥외 스포츠로서, 때로는 -30 .deg. C 정도의 저온이나 강풍이 부는 한냉 환경하에서 행하여지는 경우도 있다. 이러한 한냉환경은 신체기능을 저하시켜서 불쾌감을 증가시키므로 의복의 중요성이 더욱 강조된다. 인간과 환경 사이에 놓여 있는 스키웨어는 그 시대의 세련된 패션성이 요구될 뿐만 아니라 운동기능성, 안전성, 내구성 그리고 쾌적성을 구비하지 않으면 안된다. 따라서 환경이 인체에 미치는 영향이나 인간의 생리적 메커니즘을 인식하므로서 비로서 쾌적한 스키웨어를 만들 수 있는 것이다. 다양한 형태의 삶을 추구하는 현대인들의 관심은 점차 여가 시간의 건전한 활용 및 스포츠에 집중 되고 있다. 이러한 사회적인 경향에 발 맞추어 신소재의 스키웨어의 개발이 활발히 진행되고 있다. 예컨데 태양 광선을 흡수하는 세라믹 투입의 신소재의 개발과 체내에서 방출하는 열을 가능한 발산하지 않는, 두 가 지 기능을 합한 축열보온 소재의 스키웨어와 또 탁월한 방수. 방풍의 효과와 운동시 발생되는 수분. 열 배출 을 위한 투습의 능력이 있고 보온의 효과가 매우 높은 힐스포(HEALSPO) 코팅 소재를 사용한 스키웨어도 개발 되고 있다. 그리고 보온성과 심리적 만족감을 위한 원피스, 투피스, 쓰리피스 타입의 디자인 개발도 진행되 고 있다. 본 연구에서는 한냉하 운동시의 축열보온 소재 및 힐스포 소재와 같은 특수소재 스키웨어가 인 체에 미치는 영향을 다른 일반 소재와 비교 고찰하고, 스키웨어의 디자인에 대한 보온성의 효과를 검토하기 위하여, 저온환경에서의 피험자의 온열생리학적 반응을 측정하였다.한 신장/근력 팀의 경우보다 높은 에너지 소비량과 심박수를 보였다.찰한 결과, 세포독성 및 염색체 이상을 유발하지 않았다. 또한 동물약품으로 사용되는 치료용량 및 투약방법에 근거하여 10mg/kg 및 5, 2.5mg/kg을 1일 1회씩 4회 투여한 군에서도 암수에 상관없이 전 농도 군에서 염색체이상을 나타내지 않아 유전독성을 나타내지 않음을 관찰하였다. 특히 vitamin C와 E의 병용투여는 상승적으로 적용하여 간세포손상을 더욱 억제시킴을 알 수 있었다.mance and on TFP(Total Factor Productivity) growth which is a pure measure of firm performance. To utilize the advantage of panel data, FEM(Fixed Effect Model) and REM(Random Effect Model) were used. The empirical result shows that the entropy index as a measurement of inter-business relatedness is not significant but technological relatedness index is significant. OLS estimates on pooled data were considerably different from FEM or REM estimates on panel data. By introducing interaction effect among the three variables for business

• Journal of the Korea Society of Computer and Information
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• v.15 no.5
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• pp.103-111
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• 2010

This paper proposes an efficient data transmission strategy using adaptive-tier low transmission power schedule in a TDMA-based ad hoc MAC protocol. Since the network resource of ad hoc networks has the characteristic of reassignment due to the multiple interferences and the contention-based limited wireless channel, the efficient time slot assignment and low power transmission scheme are the main research topics in developing ad hoc algorithms. Based on the proposed scheme of interference avoidance when neighbor clusters transmit packets, this paper can minimize the total energy dissipation and maximize the utilization of time slot in each ad hoc node. Simulation demonstrates that the proposed algorithm yields 15.8 % lower energy dissipation and 4.66% higher time slot utilization compared to the ones of two-tier conventional energy dissipation model.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1495-1501
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• 2013

This study aims to figure out the effectiveness of low-carbon oriented residential regeneration by on-site improvement method. For this, we examined some technical planning elements for carbon reduction and selected standard criteria of computation on energy use-based amount of carbon emission through previous literature review and case studies. Next, based on this, we compared and analyzed three types of carbon emission in the designated renewal area in Cheongju City. The three types of carbon emission were the existing development, the redevelopment of apartment by overall removal, and the development of low-carbon oriented residential regeneration by on-site improvement method. Finally, we examined proper way to reduce carbon emission in low-carbon oriented residential regeneration.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.225-231
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• 2016

Glasshouse heating package technologies to improve energy usage efficiency in winter were developed. Heating package was composed of the ground water source heat pump with heating capacity of 105kW, the aluminum multi-layer thermal curtain with six layers of different materials and the root zone local heater with XL pipes of ${\phi}20mm$. Venlo type glasshouse($461m^2$) with the heating package was compared with the same type and area control glasshouse with the light oil boiler, the usual non-woven fabric thermal curtain with respect to the glasshouse inside temperature, relative humidity, crop growth, and heating energy consumption. The results of test in paprika cultivation glasshouses showed that the air temperature inside glasshouse with aluminum multi-layer thermal curtain was maintained $2.2^{\circ}C$ higher than that of control glasshouse in un-heating night time and the temperature in bed with root zone local heating was $4.7^{\circ}C$ higher than that in bed without local heating. Average heating coefficient of performance(COP) of the ground water source heat pump used in paprika cultivation was 3.7 and the glasshouse inside temperature was maintained at $21^{\circ}C$ of heating set up temperature. The heating energy consumptions per 10a were measured at 14,071L of light oil and 364kWh of electric power for the control glasshouse and 35,082kWh for the glasshouse applied heating package. As results, the heating cost of the glasshouse applied heating package was 87 percent lower than that of control glasshouse. The growths of paprika in glasshouses of control and applied heating package did not show any significant difference.

• Korean Journal of Community Nutrition
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• v.22 no.6
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• pp.529-542
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• 2017

Objectives: The purpose of this study was to compare the physical activity level (PAL), the physical activity pattern and the energy expenditure in male and female elementary school soccer players using the accelerometer and the physical activity diary. Methods: Twenty-five (male 11, female 14) elementary school soccer players (9-12 years) participated in this study. During their daily activities, they wore an accelerometer for seven days (five weekdays and two weekend days) and completed the physical activity diary for three days (two weekdays and one weekend day). PAL was calculated by using the physical activity diary and three equations (Pate Preschool, Freedson Children, and Freedson) were used to calculate the intensity of physical activity and energy expenditure from the counts of accelerometer. Results: The average of physical activity by day of the week, CPM (Counts Per Minute) and METs (Metabolic Equivalents) were significantly higher in males ($723.3{\pm}149.2CPM$, $2.07{\pm}0.18METs$) compared to females ($505.6{\pm}119.9CPM$, $1.79{\pm}0.20METs$), but there was no significant difference in PAEE (Physical Activity Energy Expenditure) between the two groups (males: $15.5{\pm}9.1kcal/day$, females: $11.5{\pm}6.0kcal/day$). During weekdays, physical activity intensity was significantly higher in males compared to females at lunch time and training time than at other times. In both genders, the PAL was higher during weekdays (males 1.98, females 1.89) compared to weekend (males 1.62, females 1.61) (p<0.05). Conclusions: Our study observations suggest the necessity to develop an accelerometer equation for accurately evaluating the physical activity of elementary school athletes.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.6
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• pp.169-180
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• 2018

White light-emitting diodes (LEDs) are more economical than fluorescent lights, and provide high brightness, a high lifetime expectancy, and greater durability. As LEDs are closely connected with people's daily lives, dimming control of LED is an important component in providing energy savings and improving quality of life. In visible light communications systems using these LEDs, multiple input multiple output (MIMO) technology has attracted a lot of attention, in that it can attain the channel capacity in proportion to the number of antennas. This paper analyzes the power performance of three kinds of modulation in visible light communications (VLC) systems applied space-time block code (STBC) techniques. The modulation schemes are return-to-zero on-off keying (RZ-OOK), variable pulse position modulation (VPPM), and overlapping pulse position modulation (OPPM), and dimming control was applied. The power requirements and power consumption were used as metrics to compare the power efficiency in $2{\times}2$ STBC-VLC environments under the three kinds of modulation. We confirm that dimming control affects the communications performance of each modulation scheme. VPPM showed greater consumption among the three modulations, and OPPM showed energy savings comparable to VPPM.