• 대한지역사회영양학회지
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• 제20권2호
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• pp.87-95
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• 2015

Objectives: Maintaining a balanced diet and thus health is crucial for adolescents, and the first step for balanced diet practice is meal planning. Adolescents, however, find it difficult to plan their meals. This study thus was set out to design an easier way of planning meals for adolescent girls. Methods: A dish-based target pattern for adolescent girls was tabulated, and validity of this was examined. Meal plan applying a dish-based target pattern was prepared by 150 female middle school students, and nutritional adequacies of those meal plans were examined. Validity and adequacy were tested by energy content, energy contribution ratio, nutrient adequacy ratio (NAR), probability of nutrient inadequacy, index of nutritional quality (INQ) calculation. Results: A dish-based target pattern with 11 dish groups was validated for nutritional adequacy. Though the NAR of calcium was 0.96, the INQ of calcium was 1.00. The average energy supply from the meal plans was 2,379 kcal, higher than the estimated energy requirement of a female middle school student, but the energy contribution ratio of carbohydrates, proteins, and fats were all adequate according to the acceptable macronutrient distribution range (AMDR). NAR of all nutrients examined were 1.0, except for calcium. The NAR and INQ of calcium were 0.87 and 0.75, respectively, and the meal plans at risk for calcium inadequacy was 19.30%. Conclusions: A dish-based target pattern proposed for adolescent girls was valid, but the meal plan prepared by female middle school students using this approach was high in energy and low in calcium supply. To cut down the energy supply from the meal plan, it is necessary to recommend dishes low in fat and use low fat cooking methods. To increase the calcium supply, it is important to recommend seaweed and legume group dishes with higher Ca INQ food items.

• 한국태양에너지학회 논문집
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• 제29권1호
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• pp.18-23
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• 2009

We intend to describe a 12kW building-integrated photovoltaic system which was applied into the south wall of a new building. This study showed the results that were appeared from describing the PV module manufacture and installation process, and performing generation performance analysis of BIPV system. From the result we confirmed that the generation performance of the BIPV system was changed by season. The performance ratio(PR) was about 83.6% in winter and it means that performance of this BIPV system was so good in that season. On the other hand, the PR in summer was about 75.0% dropped about 8%. It was believed that the change was influenced by the reduction of solar radiation irradiated into the PV modules by installation position and rainy spell in summer. And we also confirmed that low irradiation condition is cause of the additional loss in the total PV system. In this case, the efficiency ratio of PCS drops significantly at low input loads and the average conversion efficiency of PCS in summer was 76.4% decreased about 10% from 86% in winter.

• 동력기계공학회지
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• 제17권2호
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• pp.70-77
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• 2013

An experimental study was carried out to understand the heat transfer performance of a miniature loop heat pipes using water-based copper nanoparticles suspensions as the working fluid. The suspensions consisted of deionized water and copper nanoparticles with an average diameter of 80 nm. Effects of the cupper mass concentration and the operation pressure on the average evaporation and condensation heat transfer coefficients, the critical heat flux and the total heat resistance of the mLHPs were investigated and discussed. The pressure frequency also depends upon the evaporator temperature which has been maintained from $60^{\circ}C$ to $90^{\circ}C$. The Investigation shows 60% filling ratio gives the highest inside pressure magnitude of highest number pressure frequency at any of setting of evaporator temperature and 5wt% results the lowest heat flow resistance.

• 대한가정학회지
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• 제29권1호
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• pp.51-58
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• 1991

This study was conducted to investigate the dietary and nutritional status supplied by group feeding for blue color and white color in Seoul and Kyunggi area. The results are summarized as follows : 1. Blue color and white color of the average food supply per person per day was 1370.0g. Blue color of the total fool supply was consisted of 35.1% grain, 44.1% vegetables. White color of the total fool supply was consisted of 31.8% grain, 44.0% vegetable. The amount of milk product, fruit and fat supply were very small. 2. Blue color and white color of the ratio of main dish and side dish supplied was 69 : 31, 60.0 : 39.7. 3. Main dish all is rice. Side dish ard kinds of soupes and Jigeai Johngol in the two groups. In the kind of side dish white color much more than blue color. Dessert are scarcely supplied in the two groups. 4. The mean daily supplies of energy and 9 nutrients were above the level of the R.D.A. Blue color and white color of the mean daily amount of energy supply was 2653.0㎉ 3022.6㎉. Blue color and white color of the ratio of carbohydrate, protein, and fat supplied was 68.4%, 18.6%, 13.1%, and 62.1%, 20.9%, 17.0%. 5. Blue color and white color of the average feeding cost amounts to 460won, 812won per meal. 6. Blue color; There were high correlations in supply amoung energy, protein, fat. Carbohydrate, calcium, iron, riboflavin, niacin. White color; There were high correlation in supply amoung energy, protein, carbohydrate, calcium, iron, thiamin, riboflavin, niacin, vit-C.

• 동력기계공학회지
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• 제16권6호
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• pp.30-37
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• 2012

Effect of rib heights is found as significant parameter to enhance convective heat transfer performance under laminar and low turbulent regime. Circular ribs with different ribheight to channel height ratios, e/H = 0.05, 0.1, 0.15, are fabricated over the copper substrate respectively in a rectangular duct having 7.5 cross sectional aspect ratio. Only one rib pitch to rib height ratio (P/e = 10) has been chosen for all different height ribs. The result shows that the arithmetic average of turbulence intensity decreases with decreasing roughness height calculated between two ribs under laminar and low turbulent region. It occurs because the area of recirculation and reattachment zone also decreases with decreasing rib height. Optimum thermal enhancement factor is derived by 0.1 rib height to channel height ratio under low turbulent region but 0.15 rib height to channel height ratio gives maximum subjected to laminar flow.

• 한국태양에너지학회 논문집
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• 제37권1호
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• pp.81-90
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• 2017

We have analyzed the performance of 58 kWp photovoltaic (PV) power systems installed in Jeddah, Saudi Arabia. Performance ratio (PR) of 3 PV systems with 3 desert-type PV modules using monitoring data for 1 year showed 85.5% on average. Annual degradation rate of 5 individual modules achieved 0.26%, the regression model using monitoring data for the specified interval of one year showed 0.22%. Root mean square error (RMSE) of 6 big data analysis models for power output prediction in May 2016 was analyzed 2.94% using a support vector regression model.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1998년도 학술발표대회 논문집 제17권 1호
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• pp.147-150
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• 1998

In the case of speech synthesis, the waveform coding method with high quality is mainly used to the synthesis by analysis. Because the parameters of this coding method are not classified as both excitation and vocal tract parameters, it is difficult to apply the waveform coding method to the synthesis by rule. Thus, in order to apply the waveform coding method to the synthesis by rule, a pitch alteration is required for the prosody control. In the speech synthesis method by the conventional PSOLA technique, applying symmetric window function to asymmetric speech waveform, it occurs the unbalance phenomenon of energy according to the overlapped degree of pitch interval adjustment. In this paper to overcome the unbalance phenomenon of energy, we proposed a new method that can convert asymmetric waveform to symmetric one by time-frequency conversion. As a result, we can obtain an average spectrum distortion ratio with 6.38% according to the pitch alteration ratio.

• 설비공학논문집
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• 제22권3호
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• pp.123-129
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• 2010

The district heating users can be generally classified into two groups such as apartments and buildings. In consideration that the time zone of the maximum heat load for apartments is different from those of buildings during a day, the maximum heat supply range is presented. In case of the investigated area, the maximum heat supply is occurred at the ratio between apartments and buildings that is 65%：35%. Thus the heat supply range is increased as much as 15% if the time zone when the maximum heat load is occurred is considered.

• International Journal of Internet, Broadcasting and Communication
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• 제14권1호
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• pp.188-193
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• 2022

The energy efficiency of memory systems is an important task in designing future computer systems as memory capacity continues to increase to accommodate the growing big data. In this article, we present an energy-efficient last-level cache management policy for future mobile systems. The proposed policy makes use of low-power PCM (phase-change memory) as the main memory medium, and reduces the amount of data written to PCM, thereby saving memory energy consumptions. To do so, the policy keeps track of the modified cache lines within each cache block, and replaces the last-level cache block that incurs the smallest PCM writing upon cache replacement requests. Also, the policy considers the access bit of cache blocks along with the cache line modifications in order not to degrade the cache hit ratio. Simulation experiments using SPEC benchmarks show that the proposed policy reduces the power consumption of PCM memory by 22.7% on average without degrading performances.

• Nutritional Sciences
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• 제1권1호
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• pp.42-50
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• 1998

In this study, we evaluated the dietary fatty-acid pattern and serum fatty-acid composition of middle school students (total, 355 ; male, 182 ; female, 173), who are vulnerable to excessive and unbalanced food intakes such as fatty acids and energy. In serum lipid levels, total Chol (p<0.05) and HDL-Chol (p<0.001) levels of female students were significantly higher than those of mal, students. The average fat intake was 23-26 energy % which falls in with the current recommendation level (15-25%) for adults. Although the average P/M/S ratio of dietary fat was 1.1/1.2/1.0 which approaches the recommended ratio, the average range of $\omega$6/$\omega$3 fatty acid ratio of dietary fat was found to be 12.0-16.5, which is higher than the presently recommended range of 4 -10. Some of the very high values found in this study were partly explained by the fact that the range of individual variation of $\omega$6/$\omega$3 ratios was very large. Mean daily intake of Chol was 357-361 mg. The n3 fatty acid intake of middle school students was higher in the LFHM (high fish low meat) group than in the LFHM (low fish high meat) group. EPA and DHA intakes appeared to be significantly higher (p<0.01) in the HFLM group than in the LFHM group as expected. Dietary total $\omega$3 fatty acids (p<0.05) and EPA (p<0.01) were also negatively associated with serum AA($\omega$6) levels. Interestingly, energy intakes and dietary SEAs such as 12 : 0 (p<0.05), 14 : 0 (p<0.01) and 16 : 0 (p<0.05) were negatively associated with serum AA ($\omega$6) levels. To lower the $\omega$6/$\omega$3 ratio of dietary fatty acids for children, frequent consumption of $\omega$3 series fatty-acid rich foods such as soy bean, bean products and fish is recommended. Detailed guidelines should be developed in recommending balanced food intake and qualitative fat intake for Korean adolescents taking heterogeneous groups into consideration. In accurately evaluating fatty acid intake, it is also necessary to have the fatty acid composition data of all foods consumed in each country.