• Journal of Korea Multimedia Society
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• v.11 no.8
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• pp.1082-1092
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• 2008

In wireless sensor networks, clustering protocol such as LEACH is an efficient method to increase whole networks lifetime. However, this protocol result in high energy consumption at the cluster head node. Hence, this protocol must changes the cluster formation and cluster head node in each round to prolong the network lifetime. But this method also causes a high amount of energy consumption during the set-up process of cluster formation. In order to improve energy efficiency, in this paper, we propose a new cluster formation algorithm. In this algorithm, we define a intra cluster as the sensor nodes within close proximity of each other. In a intra cluster, a node senses and transmits data at a time on the round-robin basis. In a view of whole network, intra cluster is treated as one node. During the setup phase of a round, intra clusters are formed first and then they are re-clustered(network cluster) by choosing cluster-heads(intra clusters). In the intra cluster with a cluster-head, every member node plays the role of cluster-head on the round-robin basis. Hence, we can lengthen periodic round by a factor of intra cluster size. Also, in the steady-state phase, a node in each intra cluster senses and transmits data to its cluster-head of network cluster on the round-robin basis. As a result of analysis and comparison, our scheme reduces energy consumption of nodes, and improve the efficiency of communications in sensor networks compared with current clustering methods.

• Journal of Nutrition and Health
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• v.33 no.2
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• pp.193-201
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• 2000

This study was conducted to investigate the effectiveness of nutrition counseling on the dietary intake and nutritional status cancer patients undergoing radiotherapy treatment. The study was conducted over 6 week period and included 104 patients : 66 received nutrition counseling as the variable group of 42 male and 24 female and 38 patients received no counseling as the control group of 19 male and 19 female. Nutrition counseling was accompanied with the radiation therapy and adminstered via counseling session and distribution of printed material during radiation therapy for 6 weeks. Nutrition counseling aimed at maintaining a balanced diet and preventing weight loss of subjects, guideline used for energy and protein intake were 35kcal/kg IBW and 1.5-2.0g/kg IBW, respectively. Over the course of the study, the counseling group increased significantly in comparison to the control group's energy intake, evidenced by the counseling group's initial mean daily energy intake of 1932.0kcal, and 4 and 6 week mean energy intake values of 2046.6kcal, 2066kcal, respectively. But mean energy values of control group was 1614.3kcal at 4 week. Th energy intake per weight values and protein intake per weight values for initial, 4 and 6 week intervals for counseling group were 33.2kcal/kg, 33.7kcal/kg, 34.0kcal/kg, and 1.48g/kg, 1.58g/kg, 1.59g/kg, respectively. Based on results, nutrition counseling had positive effects on both the variety of diet and energy intake of the variable group, mostly due to an increase in dairy product and egg consumption. In addition, the percentage of counseling group patients who consumed all 5 food group increased from 48.5% to 54.5%. Sufficient energy intake and protein consumption seem to be important factors in weight loss prevention, evidenced by weight gain by subjects in the counseling group who had 36.1kcal/kg/day mean energy intake and 1.77g/kg/day mean protein intake after 4 weeks. Counseling group subjects experiencing weight loss had lower intake and 1.77g/kg/day mean protein intake after 3 weeks. Counseling group subjects experiencing weight loss had lower intakes of 29.3kcal/kg/day for energy and 1.33g/kg/day for protein during the same period. Another significant factor in weight loss prevention of the counseling group could be the variety of diet. The dietary variety scores(DVS) of both counseling and control groups differed significantly : the counseling group had a mean score of 34 while the control group of patients. At the end of the study, the mean percentage of subjects within each group having a DDS 5 was higher in the counseling group (54.5% v.s. 24.0%). In this study, nutrition counseling for cancer patients undergoing radiation therapy proved to be effective in preventing weight loss, a major complication during radiotherapy. Nutrition counseling not only increased protein and energy intake, but also had desirable effects on variety or diversity of diet.

• KIEAE Journal
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• v.15 no.3
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• pp.49-56
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• 2015

Purpose: Due to recent increase on energy consumption for light in building, many studies to mitigate this issue have been conducted. Various researches have been carried out to suggest light shelf as one of the solutions, but researches for its reflectivity is very few. In fact, existing research on light shelf shows that utilizing more than 90% of high-illumination materials causes imbalance of glare and illuminance. Method: Therefore this research aimed to evaluate the performance of light shelves depending on reflectivity and to identify proper solution through test-bed. Result: The results are following: 1) Increased reflectivity generally contributed to increase of indoor illuminance but degrade uniformity factor related with indoor comfort of light environment. 2) The $0^{\circ}fixed$ light shelf with 75% of reflectivity and width of 300mm and 40mm appeared to consume more energy than other shelves. Therefore, it is analyzed as unsuitable. 3) This research was conducted by calculating appropriate angle of light shelf around winter and summer solstices and vernal/autumnal equinox. Based on this, performance evaluation was undertaken depending on reflectivity of movable light shelf, which is activated by external sources and can be applied with lower reflectivity than fixed shelf. However, one exception was a movable shelf with width of 600mm that increased light energy consumption when 75% of reflectivity was applied. 4) Performance evaluation of fixed and movable light shelf showed that the shelf with 80% of reflectivity came up with suitable results, but 75% of reflectivity may be applied depending on the width and angle of the shelf. This research is meaningful in that estimation of appropriate reflectivity of light shelf can resolve the glare problem and improve light environment, and further research would be desirable under more diverse conditions to identify proper solution.

• Journal of Environmental Science International
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• v.25 no.3
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• pp.439-446
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• 2016

Domestic sewerage treatment plant is operated by activated sludge method and its modified method by using microorganism. In most cases, a method of using microorganism is directly controlled by the operator based on individual judgment through factors of DO, pH and ORP. In addition, under aerobic condition in bioreactor, energy consumption including excessive air injection is learned to be somewhat plenty. In order to solve this problem, in most of the process, improvement of internal recycling and activated environmental factor of microorganism were researched extensively. However, as factors are changed depending on various conditions, it is not sufficient as an indicator of judgment. As such, a research on operation of bioreactor that measures metabolic change in short time by directly measuring activated condition of microorganism using NADH fluorometer is required in reality.It is considered that the method like this could supplement problem of energy consumption being occurred in the existing treatment method and operational optimization of bioreactor would be enabled by controlling optimal air volume. Therefore, in this study, in order to obtain optimal operational indicator of bioreactor, proper air volume control test was performed and through batch test and site evaluation, possibility of NADH sensor being utilized as operational control indicator of bioreactor is intended to be analyzed. In order to compare with measured value, DO, ORP that are operational control indicator of existing bioreactor were used. As MLSS concentration was increased through batch test, NADH value was increased and site evaluation also showed similar tendency to batch test. Resultantly, it could be confirmed that changing level of NADH fluorometer was a sensor that could measure bioreactor condition effectively and optimized scale of bioreactor is considered to be utilized.

• Journal of Radiation Protection and Research
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• v.23 no.4
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• pp.243-249
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• 1998

The methodology for justification and optimization of the countermeasures related with contamination management of milk was designed based on the cost and benefit analysis. The application results were discussed for the deposition on August 15, when pasture is fully developed in Korean agricultural conditions. A dynamic food chain model DYNACON was used to estimate the time-dependent radioactivity of milk after the deposition. The considered countermeasures are (1) the ban of milk consumption (2) the substitution of clean fodder, which are effective in reducing the ingestion dose as well as simple and easy to carry out in the first year after the deposition. The total costs of the countermeasures were quantitatively estimated in terms of cost equivalent of doses and monetary costs. It is obvious that a fast reaction after the deposition is an important factor in cost effectiveness of the countermeasures. In most cases, the substitution of clean fodder was more effective countermeasure than the ban of consumption. A fast reaction after the deposition made longer justifiable/optimal duration of the countermeasure.

• Journal of Climate Change Research
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• v.1 no.3
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• pp.211-217
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• 2010

Off-road transportation sector including construction equipment, ground support equipment in airport, cargo handling equipment and agroforestry machinery have not calculated as emission source classification in 1A3e2. In this study, the statistics of oil consumption for construction, aviation, shipping and agroforestry are separated for this sector by oil type. And the greenhouse gas emission by off-road transportation emission factor in 1996 & 2006 IPCC Guidelines are calculated and compared with each other. As a result, the nationwide $CO_2$ equivalent emission from off-road transportations by the emission factor of 1996 & 2006 IPCC Guidelines are calculated as 4,919 kton/yr and 5,530 kton/yr in 2007. The contribution ratio of off-road transportation emission by this study is estimated as 5.5% to the subtotal emission from on-road transport sector.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.4
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• pp.50-61
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• 2013

In order to generate a renewable energy-Methane, anaerobic systems fed with source separated food waste from university cafeteria were studied. At first, four reactors were evaluated with same feed components; content non-mixing anaerobic reactor without leachate withdrawal/recirculation, content mixing anaerobic reactor without leachate withdrawal/recirculation, content non-mixing anaerobic reactor with leachate withdrawal/recirculation and content mixing anaerobic reactor with leachate withdrawal/recirculation. From the first study, content non-mixing anaerobic reactor with leachate withdrawal/recirculation showed the highest gas production. From further study with this system, it was observed that leachate permeation rate within anaerobic reactor was very important factor for gas generation. The higher permeation rate, the more gas production was observed. It is assumed that 1kg of gas collector weight and C/N ration above 10 in food waste may cause gas consumption in the anaerobic reactor. The gas consumption was estimated by negative pressure build-up at gas collector. The negative pressure build-up must be explained to produce Methane from Food Waste.

• Clean Technology
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• v.23 no.2
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• pp.181-187
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• 2017

The perfluorocompounds (PFCs) emitted from the semiconductor and display manufacture is treated by abatement systems which use various technologies, such as combustion, thermal, plasma, catalyst. However, it is required that the system should overcome their drawbacks with excess energy consumption and low removal efficiency. The new technology using combination of pressure swing adsorption and excess enthalpy combustion for the reduction of PFCs emissions were developed and analyzed its characteristics. PFCs concentration ratio and PFCs loss factor were calculated from measuring concentration of PFCs at the calculated by comparing concentration of PFCs at the combustor's inlet and outlet. There were performance evaluations with various gas flow for comparing energy consumption and removal efficiency with existing equipments. The concentration ratio and the loss factor of PFCs were 1.65, 8.2%, respectively, when the total gas flow of the pressure swing absorption (PSA) inlet was 204 liter per minute (LPM) and $CF_4$ concentration was 1412 ppm. In comparison with existing system at constant condition, $CF_4$ removal efficiency for a porous media combustion (PMC) showed the improvement more than 16% and the consumed energy was also reduced up to approximately 41%. Then, the total gas flow introduced into PMC and $CF_4$ concentration were 91-LPM and 2335 ppm, respectively, and the destruction and removal efficiency of $CF_4$ was about 96% at 19-LPM $CH_4$, and 40-LPM $O_2$.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.79.3-80
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• 2016

We have investigated the correlation analysis between global temperature anomaly and two main factors: geomagnetic activity (aa index) of Earth external factor and CO2 of Earth internal factor. For this, we used NOAA Global Surface Temperature anomaly (Ta) data from 1868 to 2015. The aa index indicates the geomagnetic activity measured at two anti-podal subauroral stations (Canberra Australia and Hartland England) and the CO2 data come from historical ice core records and NOAA/ESRL data. From the comparison between (Ta) and aa index, we found several interesting things, First, the linear correlation coefficient between two parameters increases until 1985 and then decreases rapidly. Second, the scattered plot between two parameters shows a boundary of the correlation tendency (positive and negative correlation) near 1985. A partial correlation of (Ta) and two main factors (aa index, CO2) also shows that the geomagnetic effect (aa index) is dominant until about 1985 and the CO2 effect becomes much more important after then. These results indicate that the CO2 effect become very an important factor since at least 1985. For a further analysis, we simply assume that Ta = Ta(aa)+Ta(CO2) and made a linear regression between (Ta) and aa index from 1868 to 2015. A linear model is then made from the linear regression between energy consumption (a proxy of CO2 effect) and Ta-Ta(aa) since 1985. Our results will be discussed in view of the prediction of global warming.

• Journal of The Korea Institute of Healthcare Architecture
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• v.17 no.1
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• pp.33-40
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• 2011

Daylight is highly beneficial for improving the indoor environmental quality and reducing building energy consumption, daylighting applications are scarcely considered, especially during the care facility design process, because of lack of previous studies on elderly- light environment and complex simulation process. Therefore, daylighting process were performed using ECOTECT, which has various advantage such as easy user interface and simple simulation processes. Moreover, dynamic daylight simulation were performed using whether data. Static simulation are performed to compute static metrics such as daylight factor, whereas dynamic simulation are performed for dynamic metrics such as daylight autonomy and useful daylight illuminance using annual weather data On the basis of daylight autonomy and useful daylight illuminance analysis result, variations in annual daylight performances. A parametric and regression analysis of the window-to-wall ratio and visible transmittance showed that daylight factor, daylight autonomy increased with window-to-wall ratio and visible transmittance. It can be concluded that this new daylight criteria. useful daylight illuminance, will enable architect to obtain better fenestration design.