• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.5 no.2 s.10
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• pp.19-28
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• 2006

In the IEEE 802.15.4a system, they require simple, economical and low power consumption transmitter and receiver to transmit low rate data and to identify distance and location. To meet these requirements, LR-WPAN system use transmitter and receiver with simple modulation and demodulation scheme. In this paper, use PPM+BPSK modulation and windowing scheme to overcome multipath fading effect. Then we apply this channel estimation scheme to LR-WPAN system and compare performance depends on transmitter scheme. Proposed method using preamble to find channel characteristic out and we compensate distorted data with that information. Therefore we can detect signal easily at the demodulation part. Simulation result shows that performance evaluation is greater at the NLOS channel than LOS channel no matter what the receiver scheme.

• Journal of Korean Society on Water Environment
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• v.35 no.6
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• pp.470-480
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• 2019

The Doam lake watershed was designated as a non-point pollution management area in 2007 to improve water quality based on watershed management implementation. There have been studies of non-point source reduction with respect to the watershed management impacting the pollutant transport of the reservoir. However, a little attention has been focused on the impact of water quality improvement by the management of the dam operation or the guidelines on the dam operation. In this study, the impact of in-lake management practices combined with watershed management is analyzed, and the appropriate guidelines on the operation of the dam are suggested. The integrated modeling system by coupling with the watershed model (HSPF) and reservoir water quality model (CE-QUAL-W2) was applied for analyzing the impact of water quality management practices. A scenario implemented with sedimentation basin and suspended matter barrier showed decrease in SS concentration up to 4.6%. The SS concentration increased in the scenarios adjusting withdrawal location from EL.673 m to the upper direction(EL.683 m and EL.688 m). The water quality was comparably high when the scenario implemented all in-lake practices with water intake at EL.673 m. However, there was improvement in water quality when the height of the water intake was moved to EL.688 m during the summer by preventing sediments inflow after the rainfall. Therefore, to manage water quality of the Doam lake, it is essential to control the water quality by modulating the height of water intake through consistent turbidity monitoring during rainfall.

• Resources Recycling
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• v.25 no.4
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• pp.23-31
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• 2016

It was found that there was no problem in recycling by-products (waste rock and tailings) from Yangyang iron mine themselves through matter conversion because they are not hazardous according to results of KSLT method. In case of using tailings as sub-materials of cement, it recommended the use of less than 3% tailings dosage not to exceed 0.6% of total alkali ($R_2O$) content based on standard quality of portland cement (KS L 5201). Non sintered eco-brick corresponding to class 1 quality of recycled clay brick (KS I 3013) can replace 15% of cement with tailings and 100% of general fine aggregate with waste rock from iron mine. As mentioned above, recycling the by-products (waste rock and tailings) as sub-materials of cement and non sintered eco-brick could gain both environmental and economic benefits, that is, reduction of scale and maintenance cost of tailing ponds, decrease of energy use and $CO_2$ emission.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.217-222
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• 2007

Since 1973, we attain a successful achievement of nation-wide afforestation such as a thick forest and heaped-up leaves. However, the higher of the formation density in forest, the more dangerous to be a large-scale forest fire whenever fire occurs. According to the type of forest in the country, 42% of the forest is occupied by conifer forest that are highly flammable, and the distribution of forest age is in a transition period from immature forest to mature one. And the structure is too weak to the forest fire for the occurrence and spread because there are too many scrub and shrub trees in the forest. As a matter of course, it is on the increase of the thinning-forest that can shift the forest structure from a weak on forest fire to a strong one nowaday. In other words, thinning-forest has primary purposes such as the promotion of producing forest trees, production of excellent timbers, and build-up of public forest area. Furthermore, in some reports, the reduction of ladder fuel by eliminating the vertical/horizontal fuel in a forest and ensuring spaces in the forest can decrease the occurrence of forest fire and the risk of spread of burning as by-effect. Therefore, this study is designed to clarify the relation with the risk of forest fire by an on-spat-investigation of the characteristics of forest composition on the thinning and the non-thinning area.

• Archives of design research
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• v.16 no.2
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• pp.171-178
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• 2003

The visual, sensible and social situation that the modern digital technologies create became the background for the works of architects in extreme modernism and their space modeling suggested another possibility that was emancipated from the restriction of a property of matter and gravity in the existing space. The architecture design process using the digital technology has been attempted in diverse ways and summarized with several characteristics such as displacement, nonlinear space, flexibility of space and non-Euclidean geometry system. However, the conceptual and very technical design process that is called as digital architecture has been indiscriminately used with mixed meanings and the common features and differences between works and theories are not studied. This study aims to classify and identify the digital architecture by type as analyzing the non-linear composition process that is common in the digital architecture.

• Journal of the Ergonomics Society of Korea
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• v.34 no.5
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• pp.455-467
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• 2015

Objective: The present study suggested practical measures for successful patent registration based on a review of success and failure cases of patent application filed based on inventions obtained from physical ergonomics research. Background: The protection of intellectual property (IP) contributes to economic growth and competitiveness and facilitates innovation and creativity. IP rights are pursued on research findings for effective technology transfer and commercialization; however, a patent application can be rejected if patentability requirements such as patent eligible subject matter, utility for industrial application, novelty, or non-obviousness are not satisfied. Method: Three successful and three failed cases of patent applications based on physical ergonomics research were reviewed, critical reasons for their successes and failures were examined, and measures were proposed to avoid failures in patent registration. Results: The following measures were identified based on the patent application case review. First, abstract ideas including logical procedures and/or mathematical formulas need to include use of tangible apparatus and methods in idea realization. Second, the provision of grace period inventor disclosure exception needs to be properly followed in case an invention is disclosed before filing of patent application. Lastly, a comprehensive analysis of prior art published or publicly known anywhere in the world and a claim preparation of distinguished, non-trivial features compared to prior art solutions are needed to avoid possible violation of novelty and non-obviousness. Application: The proposed measures can help to prepare a patent application with patent eligibility.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.250-257
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• 2001

An experiment was conducted to determine the effects of phytase supplementation to the diets containing different levels of non-phytate phosphorus (NPP). A $3{\times}2$ factorial arrangement of treatments was employed. There were three dietary NPP levels of control (C) (0.45% for starter diet and 0.35% for grower diet), C-0.1% NPP (0.35% for starter diet and 0.25% for grower diet), and C-0.2% NPP (0.25% for starter diet and 0.15% for grower diet) and two phytase levels (0 and 500 U/kg). Reduced dietary NPP decreased feed intake and weight gain and increased mortality whereas dietary phytase increased feed intake and weight gain and decreased mortality. Supplemental phytase improved availabilities of dry matter, crude fat, ash, P, Zn, Mg, and Cu whereas dietary NPP level did not affect availabilities of nutrients except decreased Zn availability and increased Cu availability in reduced NPP diets. Nutrient retention of N, ash, Ca, P, Mg, and Zn were linearly decreased as dietary NPP levels reduced but dietary phytase increased their retention. Reduced dietary NPP increased ash excretion but decreased P and Cu excretion while dietary phytase decreased N excretion. Weight, length, girth and contents of ash, Ca, P and Mg of tibia linearly decreased as dietary NPP levels reduced. Dietary phytase increased length and ash content of tibia. It is concluded that dietary phytase can reduce P excretion and alleviate adverse affects caused by feeding low dietary NPP. Effects of phytase were greater in the lower NPP diets.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.206-210
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• 2001

Six Holstein$\times$indigenous multiparous dairy cows, $60{\pm}8$ days in milk, were used in a double $3{\times}3$ Latin square design to investigate the efficiency of milk production. The dairy cows were randomly allocated to total mixed rations (TMR) containing ground corn, ground corn plus cassava chips 50:50 and cassava chips as main sources of total non-fiber carbohydrates. Ether extract and calculated energy intakes for dairy cows fed TMR containing cassava chips were lower (p<0.05) than those fed TMR containing ground corn and ground corn plus cassava chips 50:50. There were no differences (p>0.05) in daily DM intake (3.51, 3.41 and 3.29% BW), in 4% fat corrected milk (19.66, 20.59 and 20.23%), in milk protein (3.37, 3.27 and 3.33%), and in solids-not-fat (9.03, 8.90 and 8.99%) but there were differences in cost of diets per kg of 4% fat corrected milk (40.75, 34.33 and 28.17%; p<0.01) for dairy cows fed TMR containing ground corn, ground corn plus cassava chips 50:50, and cassava chips. It can be concluded that the efficiency of milk production (4% fat corrected milk per dry matter intake) for dairy cows fed TMR containing cassava was greater than for those fed TMR containing corn.

• Journal of Ecology and Environment
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• v.41 no.2
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• pp.34-44
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• 2017

Background: Monitoring terrestrial vegetation cover condition is important to evaluate its current condition and to identify potential vulnerabilities. Due to simplicity and low cost, point intercept method has been widely used in evaluating grassland surface and quantifying cover conditions. Field-based digital photography method is gaining popularity for the purpose of cover estimate, as it can reduce field time and enable additional analysis in the future. However, the caveats and uncertainty among field-based vegetation cover estimation methods is not well known, especially across a wide range of cover conditions. We compared cover estimates from point intercept and digital photography methods with varying sampling intensities (25, 49, and 100 points within an image), across 61 transects in typical steppe, forest steppe, and desert steppe in central Mongolia. We classified three photosynthetic groups of cover important to grassland ecosystem functioning: photosynthetic vegetation, non-photosynthetic vegetation, and bare soil. We also acquired normalized difference vegetation index from satellite image comparison with the field-based cover. Results: Photosynthetic vegetation estimates by point intercept method were correlated with normalized difference vegetation index, with improvement when non-photosynthetic vegetation was combined. For digital photography method, photosynthetic and non-photosynthetic vegetation estimates showed no correlation with normalized difference vegetation index, but combining of both showed moderate and significant correlation, which slightly increased with greater sampling intensity. Conclusions: Results imply that varying greenness is playing an important role in classification accuracy confusion. We suggest adopting measures to reduce observer bias and better distinguishing greenness levels in combination with multispectral indices to improve estimates on dry matter.

• Journal of Environmental Health Sciences
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• v.41 no.4
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• pp.259-267
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• 2015

Objectives: This study evaluated the regional and seasonal concentrations of ambient hazardous heavy metals in an industrial complex area in Daegu City. Methods: A total of 64 SPM (Suspended Particulate Matter) samples were collected in non-industrial and industrial areas during 2014 and were analyzed for hazardous heavy metals elements (As, Cd, Mn, Ni, Pb) with ICP after acid extraction. Results: SPM and hazardous heavy metals concentrations showed regional (industrial complex area>non-industrial complex area) and seasonal (spring, winter>fall, summer) variations. All of the hazardous heavy metals were influenced by anthropogenic sources. The pollution index of hazardous heavy metals was very low, showing roughly one-quarter of the level of the air quality guidelines of WHO. The correlation analysis among SPM and hazardous heavy metals indicated that components of non-industrial complex areas were more related to each other than those of industrial complex areas, and the correlation in the winter was higher than in other seasons. Conclusion: It is necessary to control air pollution sources and establish related policy because hazardous heavy metals from industrial areas can influence residential areas.