• Journal of the Korea Society of Computer and Information
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• v.17 no.12
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• pp.137-148
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• 2012

In this paper, we proposed the location-aware coordinate routing algorithm for improving the performance of routing algorithm by using ZigBee in Smart Grid environment. A distributed address allocation scheme used an existing algorithm that has wasted in address space. The x, y and z coordinate axes from divided address space of 16 bit to solve this problems. However, coordinate routing does not take account of wireless link condition. If wiress link condition is not considered, when the routing table is updated, the nodes with bad link conditions are updated in the routing table and can be chosen as the next hop. This brings out the retransmissions because of received packet's errors. Also, because of these retransmissions, additional power is consumed. In this paper, we propose the location-aware coordinate routing algorithm considering wiress link condition, where reliable data transmission is made and the consumed enegy is minimize. and we compared and connected region and transition region of ZigBee location based routing in the aspect of average number of multi hops, subordinate packet delivery ratio, delay time, and energy consumption of proposed algorithm. It turned out that there were improvements in performances of each items.

• Journal of the Institute of Convergence Signal Processing
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• v.11 no.4
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• pp.326-331
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• 2010

This paper has proposed and experimentally demonstrated a new BLU using an LED and an acryl, which is specially focused on the implementation about the guiding effect of an acryl luminous by the LED. While the conventional BLU using a fluorescent lamp is generally and widely used, it shows big power consumption with a short life even more too thick to hold on the wall. To solve such demerits, we propose a new method for a BLU using an LED and an acryl in this paper. This BLU system has various scratches on the surface of acryl to get diffusion effect of light, and has been included an embedded board that can dynamically control the colors and the intensity of the BLU through the Internet. We have conducted computer simulations to find out the optimal scratch pattern on the surface of the acryl for the backlight system. Based on the resulted out simulation. The the optimal scratch pattern signs has been developed. The simulation result shows 2,673Lux an average for a luminous intensity test, and the other hand, experiential result shows 2,554Lux. From the experiments, it is possible for the proposed BLU system to be used for real advertisements.

• KIPS Transactions on Computer and Communication Systems
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• v.2 no.3
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• pp.111-116
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• 2013

With technology scaling, soft error rate has greatly increased in embedded systems. Due to high performance and low power consumption, VLIW (Very Long Instruction Word) architectures have been widely used in embedded systems and thus many researches have been studied to improve the reliability of a system by duplicating instructions in VLIW architectures. However, existing studies have ignored the feature, called VLES (Variable Length Execution Set), which is adopted in most modern VLIW architectures to reduce code size. In this paper, we propose how to support instruction duplication in VLIW architecture with VLES. Our experimental results demonstrate that a VLIW architecture with VLES shows 64% code size decrement on average at the cost of about 4% additional cell area as compared to the case of a VLIW architecture without VLES when instruction duplication is applied to both architectures. Also, it is shown that the case with VLES does not cause extra execution time compared to the case without VLES.

• Journal of the Korea Society of Computer and Information
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• v.14 no.12
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• pp.17-24
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• 2009

More recently, the Green Computing have become a important issue in all fields of industry. The energy efficiency cannot be over-emphasized. Microprocessor companies such as Intel Corporation design processors with taking both energy efficiency and performance into account. Nevertheless, general computer users typically utilize the CPU overclocking to enhance the application performance. The overclocking is traditionally considered as an evil in terms of the power consumption. In this paper, we present effective CPU overclocking schemes, which raise CPU frequency while keeping current CPU supply voltage for energy reduction and performance improvement. The proposed scheme gain both energy reduction and performance improvement. Evaluation results show that our proposed schemes reduce the processor execution time as much as 17% and total computer system energy as much as 5%, respectively. In addition, our effective CPU overclocking schemes reduce the Energy Delay Product (EDP) as much as 22%, on average.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.17 no.4
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• pp.198-204
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• 2024

LDPC, known for its excellent error correction capability, has been adopted as the channel coding technique in the IRIG 106 standard, which is standard for data transmission methods in the aerospace field. Iterative codes such as LDPC require large block sizes and number of iterations in order to improve performance. However, large number of iterations induce computational complexity and power consumption. To solve these problems, this paper presents a parity check-based early stop algorithm that reduces the average number of iterations while maintaining the same performance. BER performance and iteration reduction amounts are compared between early stop algorithm and conventional method that has fixed number of iterations for various coding rate and information bit size defined in the IRIG 106 standard. Through simulation results, we confirmed required iteration numbers are reduced about 50% above without performance loss.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.89-97
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• 2007

This study analyzed the lpcd of 25 districts in Seoul using random samples of residents in Seoul selected by computer selecting system. By classifying these samples according to the type of houses(tenement houses, apartment houses and detached houses), the type of districts, the effects of the number of residents in a house and the type of the houses on tap water use are analyzed. From these samples, the consumption of tap water per capita day(lpcd) in Seoul can be estimated statistically. It is also observed that the lpcd decreases as the flat-dwellers increase. As the dwellers increase from 1 to 2, from 2 to 3, from 3 to 4 and from 4 to 5, lpcd has decreased by 47.6%, 20.8%, 16.9%, and 9.0%, respectively. The regression curve, which fits the tendency of decrease well, is represented by an power function. And the estimated linear regression equation shows that the average decreasing rate of lpcd as flat dwellers increasing is 12%.

• Journal of the Korean Applied Science and Technology
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• v.37 no.2
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• pp.214-223
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• 2020

This study evaluated CO₂ removal efficiency, monitoring data analysis / evaluation efficiency and energy reduction efficiency in the liquor factory by L-alanine applied scrubber. The average removal rate of the scrubber was 90.45%, and it was confirmed that the removal efficiency was excellent above 10,000ppm of inlet CO₂ concentration. After the scrubber operation, the CO₂ concentration in the workplace was maintained under 2,000ppm(the carbon dioxide reduction efficiency was about 74%). and the energy saving efficiency was calculated to 7.26% by reducing the power consumption. As a result of applying the developed product, it was possible to improve the working environment of workers by reducing the carbon dioxide concentration in the workplace at low concentration without ventilation, and to reduce the energy consumption. Therefore, it is expected that the scrubber will be useful as a high CO₂ removal process in food and liquor factories.

• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.1
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• pp.22-27
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• 2023

This experiment was conducted to confirm the possibility of preparing Sorghum×sudangrass hybrid artificial hay using far-infrared rays in Korea. The machine used in this experiment is a drying device based on far-infrared rays, and is designed to control temperature, air flow rate, far-infrared radiation amount, and air flow speed. The Sorghum×sudangrass hybrids harvested in late September were wilted in the field for one day, and a drying test was performed on them. Conditions for drying were performed by selecting a total of 7 conditions, and each condition induced a change in radiation amount in a single condition (42%) and two steps (4 treatments) and three steps (2 treatments). The speed of the air flow in the device was fixed at 60 m/s, and the run time was changed to 30, 60, and 90 minutes. The average dry matter (DM) content was 82.84%. The DM content was 59.94 and 76.91%, respectively, in drying conditions 1 and 3, which were not suitable for hay. In terms of drying rate, it was significantly higher than 80% in the 5, 6 and 7 treatment, and power consumption was slightly high with an average of 5.7 kw/h. As for the feed value according to each drying condition, the crude protein (CP) content increased as the drying time increased, and there was no significant difference between treatments in ADF, NDF, IVDMD and TDN content. In terms of RFV, treatment 1, which is a single condition, was significantly lower than the complex condition. Through the above results, it was determined that the drying conditions 4 and 5 were the most advantageous when considering the drying speed, power consumption, and quality.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.11
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• pp.33-40
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• 2005

This paper describes a design of FFT/IFFT Core(FFT256/2k), which is an essential block in terrestrial DMB modem. It has four operation modes including 256/512/1024/2048-point FFT/IFFT in order to support the Eureka-147 transmission modes. The hybrid architecture, which is composed of R2SDF and R2SDC structure, reduces memory by $62\%$ compared to R2SDC structure, and the SQNR performance is improved by TS_CBFP(Two Step Convergent Block Floating Point). Timing simulation results show that it can operate up to 50MHz(a)2.5-V, resulting that a 2048-point FFT/IFFT can be computed in 41-us. The FFT256/2k core designed in Verilog-HDL has about 68,400 gates and 58,130 RAM. The average power consumption estimated using switching activity is about 113-mW, and the total average SQNR of over 50-dB is achieved. The functionality of the core was fully verified by FPGA implementation.

• Korean Journal of Community Nutrition
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• v.5 no.2
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• pp.297-306
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• 2000

In order to examine the relationship between the number of different foods consumed and nutrient intake, one-day food consumption were surveyed by 24-hour recall from a sample of 287 individuals(20-49 years) living in Daejon City. The number of consumed food items did not include seasonings except red pepper power, sugar, oil, and soybean paste when used in large amounts(DVS). The number, including all seasonings except salt and vinegar(DVSS), was also counted. Of the total subjects, 43.6%(DVS) or 39.0%(DVSS) consumed 18-23 daily different foods with an average of 20.2 or 22.9, respectively. As the DVS increased, daily intakes of total foods and most food groups were elevated. Cereals however were not changed and eggs were decreased with increasing DVS. Energy and nutrient intakes and their mean adequacy ratio(MAR) and index of nutritional quality(INQ) also show positive correlations with DVS. MAR equal to or greater than($\geq$) 0.75 was taken as a cut-off point for nutritional adequacy. In that case, the mean INQ was shown to be $\geq$1. MRI(10) for energy and 9 nutrients and MAR(3) for Ca, vitamin A, and riboflavin were estimated. Form a regression analysis, when MAR(10) was 0.75, the DVS and DVSS were assumed to be 19.6 and 22.2, respectively. And when MAR(3) was 0.75, the DVS and DVSS were assumed to be 31.6 and 34.6, respectively. However the subjects whose MAR(3) was 0.75(0.7-0.8) 23.8(DVS) or 26.6(DVSS) different foods in average, and their mean intakes of energy and all nutrients, except vitamin A, were ranged at 85-100% of the RDA. Of the 74 subjects who consumed DVS$\geq$24, 24 to 42 numbers took 〈75% RDA of Fe, Ca, riboflavin, and vitamin A. And five of 7 who consumed DVS$\geq$32 took $\geq$125%RDA of protein, which showed concerns of overnutrition in case of DVS$\geq$32. Form the above results it could be suggested that a daily intake of 24-32(or 28) of DVS or 27-35(or 31) of DVSS was recommendable for an optimal nutritional of all nutrients if the variety of food groups and sufficient intake of vitamin A and calcium were emphasized together.