• Korean Journal of Hydrosciences
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• v.8
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• pp.57-68
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• 1997

The daily soil water contents were obtained from the time domain reflectometry(TDR) method and energy balance-water budget approach with eddy correlation at the two small semiarid watersheds of Lucky Hills and Kendall during the summer rainy period. There was a comaprison of daily soil water content measured and estimated from these two different approaches. The comparison is valuable to evaluate the accuracy of current soil water content measuring system using TDR and energy balance-water budget approach using eddy correlation method at a small watershed scale. The degree of simiarity between the regressions of these two methods of measuring soil water content was explained by determining the correlations between these methods. Simple linear regression analyses showed that soil water content measured from TDR method was responsible for 58% and 63% of the variations estimated from energy balance-water budget approach with edy correlation at Lucky Hills and Kendall, respectively. The scatter plots and the regression analyses revealed that two different approaches for soil water content measurement at a small watershed scale have no significant difference.

• Journal of Soil and Groundwater Environment
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• v.16 no.5
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• pp.82-89
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• 2011

Understanding snowmelt movement to the watershed is crucial for both climate change and hydrological studies because the snowmelt is a significant component of groundwater and surface runoff in temperature area. In this work, a new energy balance budget algorithm has been developed for melting snow from a snowpack at the Central Sierra Snow Laboratory (CSSL) in California, US. Using two sets of experiments, artificial rain-on-snow experiments and observations of diel variations, carried out in the winter of 2002 and 2003, we investigate how to calculate the amount of snowmelt from the snowpack using radiation energy and air temperature. To address the effect of air temperature, we calculate the integrated daily solar radiation energy input, and the integrated discharge of snowmelt under the snowpack and the energy required to generate such an amount of meltwater. The difference between the two is the excess (or deficit) energy input and we compare this energy to the average daily temperature. The resulting empirical relationship is used to calculate the instantaneous snowmelt rate in the model used by Lee et al. (2008a; 2010), in addition to the net-short radiation. If for a given 10 minute interval, the energy obtained by the melt calculation is negative, then no melt is generated. The input energy from the sun is considered to be used to increase the temperature of the snowpack. Positive energy is used for melting snow for the 10-minute interval. Using this energy budget algorithm, we optimize the intrinsic permeability of the snowpack for the two sets of experiments using one-dimensional water percolation model, which are $52.5{\times}10^{-10}m^2$ and $75{\times}10^{-10}m^2$ for the artificial rain-on-snow experiments and observations of diel variation, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.801-806
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• 2013

Spiny lebbeid shrimp Lebbeus groenlandicus larvae were reared in the laboratory to estimate the energy budget from the zoeal to the post-larval stage. Energy expended by larvae on growth and respiration was determined from values for feeding, growth, molting, and metabolism. We calculated that 16.22 J were used for growth throughout all larval stages. Energy loss during molting was estimated as 1.03 J, and energy used for respiration was estimated as 1.31 J. Energy taken in by feeding was estimated as 77.16 J, while the sum of energies expended in excretion and egestion was 58.61 J. Larvae were estimated to assimilate 24.6% of ingested food as energy and to use ~85% of the assimilated energy for somatic growth. Gross growth efficiency ($K_1$) and net growth efficiency ($K_2$) were shown to be ~22% and 93%, respectively. Maintenance costs of respiration were estimated as ~9.7% of assimilated energy.

• Journal of the Korean Solar Energy Society
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• v.37 no.6
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• pp.103-114
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• 2017

Radiation energy budget was analyzed using observation data from the Weather Information Service Engine (WISE) energy flux tower on the Seoul metropolitan area. Among observation data from the 13 energy flux towers, we used meteorological variables, radiation data (upward and downward short wave, upward and downward long wave, net short wave, net long wave and net radiation), albedo and emissivity for 15 months from July 2016 to September 2017. Although Gajwa (205) and Ttuksumm (216) sites located in urban, the albedo was relatively high due to the surround environment by glass wall buildings and the Han river around the sites. And Bucheon (209) site located in the suburb represented generally low emissivity. As a result, the albedo decreased and the emissivity increased in the city center. In the Seoul metropolitan area, the net radiation energy is $73.9W/m^2$ that the radiation budget of the surface is absorbed into the atmosphere. According to WISE observation data, it can be seen that observation at each sites are influenced by the surrounding environment.

• International journal of advanced smart convergence
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• v.7 no.3
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• pp.101-109
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• 2018

In this paper, we propose an adaptive filtering scheme of connection requests for the defense of malicious energy consumption attacks against wireless computing devices with limited energy budget. The energy consumption attack tries to consume the battery energy of a wireless device with repeated connection requests and shut down the wireless device by exhausting its energy budget. The proposed scheme blocks a connection request of the energy consumption attack in the middle, if the same connection request is repeated and its request result is failed continuously. In order to avoid the blocking of innocuous mistakes of normal users, the scheme gives another chance to allow connection request after a fixed blocking time. The scheme changes the blocking time adaptively by comparing the message arriving ate during non-blocking period and that during blocking period. Evaluation shows that the proposed defense scheme saves up to 94% energy consumption compared to the non-defense case.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.2
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• pp.168-175
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• 2016

We conducted a 90-day feeding experiment to evaluate the growth and energy budget of the sea cucumber Apostichopus japonicus. Sea cucumbers with a mean initial wet body weight of 3.03±0.06 g were fed one of the following three diets: an eel fecal solid diet, rainbow trout fecal solid diet, or a commercial diet at a water temperature of 17±1℃ and salinity of 32±1 psu. The results suggested that the diets affected the final body weight, specific growth rate (SGR), food ingestion, feces production ratio, and hence the growth and energy budget of the sea cucumbers. Sea cucumbers fed the eel and rainbow trout fecal solid diets showed poorer energy absorption, assimilation, and growth than those fed the commercial diet. The sea cucumbers fed the commercial diet had a significantly higher SGR and proportion of energy used for growth than those fed the other two diets. Sea cucumbers fed the rainbow trout fecal solid diet showed a comparatively higher ingestion rate and feces production ratio than those fed the commercial diet. The eel and rainbow trout fecal solid diets, therefore, were not suitable for sea cucumbers in intensive cultivation. Our findings will facilitate further development of more appropriate diets for culture of sea cucumber.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.4
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• pp.358-364
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• 2003

Gross energy intake fecal, nitrogen excretory and metabolized energy of snotted halibut juvenile, Eopsetta grigorjewi, fed on Tigriopus iaponicus (Group A) and the enriched Artemia nauplii (Group B), were quantitatively investigated and represented as balance equations of energy and material. Absorption efficiency (AE), gross conversion efficiency $(K_1)$ and net conversion efnciency $(K_2)$ were also estimated to understand the changes in efficiency by the prey Gross energy intake, fecal, nitrogen excretory, metabolized and growth energy of Group A were $2.790\pm0.247,\;0.495\pm0.046,\;0.018\pm0.003,\;0.214\pm0.047\;cal\;mg^{-1}\;day^{-1}$ and $2.063\;cal\;mg^{-1}\;day^{-1},$ respectively. The same parameters of Group B were $4.801\pm0.165,\;0.579\pm0.031,\;0.055\pm0.010,\;0.306\pm0.048\;cal\;mg^{-1}\;day^{-1}$ and $3.861\;cal\;mg^{-1}\;day^{-1},$ respectively. Energy budget of Group A and B were represented as 100 C= 7.67 M+17.7 F+0.65 U+73.94 G and 100C=6.37 M+ 12.1 F+1.15 U+80.42 G, respectively, where C, M, F, U, and G represent gross energy intake, metabolized energy, fecal energy, nitrogen excretory (non-fecal) energy and growth energy, respectively. AEs of Croup A and B were $81.52\pm1.89,\;86.79\pm0.70\%,$ respectively, with significant difference at p=0.01 level. However, $K_1\;and K_2$ of Group A and B showed no significant difference at p=0.01 level, with $74.21\pm6.57,\;80.48\pm2.76\%\;and\;91.17\pm7.26,\;92.74\pm2.69\%$ respectively. These results suggest that T. japonicus is a possible substitute for Artemia nauplii for the snotted halibut juvenile.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.60-61
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• 2006

New Energy and Industrial Technology Development Organization (NEDO) promotes R&D that individual private sector enterprises can not undertake by themselves. To do this, it utilizes an extensive network that supports cooperation between industries, universities, and public research organizations. NEDO's government-funded R&D budget for FY2005 totals approximately 148.8 billion yen. Fuel cells and hydrogen technology development project is one of NEDO's emphasizing projects. The budget size was ${\yen}$20.8 billion, corresponding to about 60% of annual expenditure of Japanese government for fuel cells in FY2005. These projects consist of 8 programs as follows.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.2
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• pp.128-138
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• 2011

In this study, energy budget was estimated to produce an efficient artificial seed. And it needs to enhance fisheries productivity of sandfish, A. japonicus. In order to estimate energy budget of the sandfish, A. japonicus juvenile fed on nonriched Artemia nauplii (NA) and the enriched Artemia nauplii (EA), of sandfish were reared at constant condition of seawater temperature of natural temperature (NT) and heated temperature (HT). During the reared period, energy used by the reared juveniles were calculated from estimates of data on ingestion, growth, oxygen consumption, nitrogen excretion and energy content. Energy budget of NT-NA, NT-EA, HT-NA and HT-EA were represented as 100C=66.49G+21.28M+0.78F+1.44U, 100C=67.54G+21.40M+9.39F+1.67U, 100C=66.86G+22.66M+8.01F+2.47U and 100C=67.06G+22.96M+7.70F+2.28U. The assimilation efficiency estimated NT-NA, NT-EA, HT-NA and HTEA were represented as 87.78%, 88.94%, 89.52% and 90.02%. Gross growth efficiency estimated NT-NA, NT-EA, HT-NA and HT-EA were represented as 66.49%, 67.54%, 66.86% and 67.06%. Net growth efficiency estimated NT-NA, NT-EA, HT-NA and HT-EA were represented as 75.75%, 75.94%, 74.68% and 74.49%. In this results, two ways could be considered to produce an efficient artificial seed of sandfish. To hasten the growth of sandfish juvenile, heated seawater (HT) and enriched Artemia nauplii (EA) should be inputted to reared condition. And to increase the energy efficiency, natural seawater (NT) and enriched Artemia nauplii (EA) should be inputted to reared condition.

• Journal of Hydrogen and New Energy
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• v.21 no.2
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• pp.143-148
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• 2010

Research and Development (R&D) investment of hydrogen and fuel cell, funded by government from 2007 to 2008 in Korea, has been analyzed. R&D investment of hydrogen and fuel cell in 2008 would see 9% and 29% of total budget in the field of renewable energy, respectively. It was found that R&D investment is mainly dependent on mission of Ministry in Korea. Basic and apply research would be mainly invested by Ministry of Education, Science and Technology (MEST), while development research would be conducted by Ministry of Knowledge Economy (MKE). In R&D investment by performer, hydrogen technology would be conducted by government-funded institute and university. It was also shown that funds for hydrogen production have been much supported than hydrogen storage. Meanwhile, fuel cell would be mainly conducted by major companies. It was also shown that funds for proton exchange membrane fuel cell (PEMFC) have been much invested than other technology in fuel cell.