• Journal of Environmental Science International
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• v.22 no.7
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• pp.873-884
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• 2013

This study was carried out to establish the conservation plan of specific plants by surveying and analyse the individuals and the environment of habitats on specific plants designated by Juwangsan national park office. The specific plants were 14 species including Berchemia berchemiaefolia, Hylotelephium ussuriense, Aristolochia manshuriensis, Lilium cernuum, Thalictrum coreanum, Exochorda serratifolia, Lilium distichum, Aristolochia contorta, Jeffersonia dubia, Eleutherococcus senticosus, Salix chaenomeloids, Eranthis stellata, Scopolia japonica, and Paeonia japonica. The habitats of specific plants were 40 sites including Berchemia berchemiaefolia of 11 sites, Hylotelephium ussuriense of 8 sites, Lilium cernuum and Thalictrum coreanum of each 3 sites, Exochorda serratifolia of 2 sites, and Lilium distichum, Aristolochia contorta, Jeffersonia dubia, Eleutherococcus senticosus, Salix chaenomeloids, Eranthis stellata, Scopolia japonica and Paeonia japonica of each 1 site. The altitude was the most in 300~400 m. In direction, NW was the most, and it showed SW in that order. The slope angle was the most in 0~10%, and the cliff showed in that order. In the results of species composition by stratum layer, Berchemia berchemiaefolia had the most, 15 species, in tree layer. In shrub and herb layer, this had the most as 20 species and 29 species, too. The species that occupied the largest size was Salix chaenomeloids in 2,500 $m^2$, and Jeffersonia dubia showed 1,500 $m^2$ in that order. The conservation of specific plants is to accomplish the ex situ and in situ conservation at the same time.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.5 no.4
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• pp.47-63
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• 1994

An important parameter in characterizing mobile communication channel is delay spread. This paper presents the results of measured delay profiles and calculated distribution funcations of delay spread for typical cellular service environments at Taejon and vicinities. The measurement system uses 1023 chip length, 5 Mbps PN code and sliding correlation method. It has been evaluated by using commercial hardware channel simulator for reliability of out data. As results the value of mean delay spread is 2.08 $\mu\textrm{s}$for suburban area. 2.12 $\mu\textrm{s}$ for urban area and 1.3 $\mu\textrm{s}$ for national/local road. Delay spread is less then 3.4$\mu\textrm{s}$, 2.8$\mu\textrm{s}$ and 1.5 $\mu\textrm{s}$ for probability of 50% and 4.5$\mu\textrm{s}$, 4.2$\mu\textrm{s}$ and 2.9$\mu\textrm{s}$ for probability of 90% at each tested site. The difference of delay spread is within 7% between going and returning status along same street. In this experiment, we found delay spread for suburban area is larger than reported foreign test results.

• Journal of the Economic Geographical Society of Korea
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• v.1 no.1
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• pp.81-112
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• 1998

This study reviews the industrialization process of the United States-Mexico Borderlands and the economic relations between the U.S. and Mexico and examines their impact on the borderlands. Main factor in the industrialization of the borderlands was the U.S. investment on the maquiladora program of Mexico since 1965. It contributed to the increase in employment and population of borderlands and the development of service industries. Low wage level of Mexico induced not only standardized labor-intensive industries but also the high-tech automated industries because they still use a lot of labor in manufacturing and assembly process, while the functions of management. R & D, and distribution remained in the U.S. This is a typical case of international division of labor and satellite industrial district. The rules of origin in NAFTA, however forced branch Plants of multinational companies to form the local linkages between firms.

• International Journal of Concrete Structures and Materials
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• v.11 no.1
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• pp.171-183
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• 2017

Strengthening reinforced concrete (RC) beams with openings by using aramid fiber reinforcement polymers (AFRP) on the beams' surfaces offers a useful solution for upgrading concrete structures to carry heavy loads. This paper presents a repairing technique of the AFRP sheets that effectively strengthens RC beams, controls both the failure modes and the stress distribution around the beam chords and enhances the serviceability (deflection produced under working loads be sufficiently small and cracking be controlled) of pre-cracked RC beams with openings. To investigate the possible damage that was caused by the service load and to simulate the structure behavior in the site, a comprehensive experimental study was performed. Two unstrengthened control beams, four beams that were pre-cracked before the application of the AFRP sheets and one beam that was strengthened without pre-cracking were tested. Cracking was first induced, followed by repair using various orientations of AFRP sheets, and then the beams were tested to failure. This load was kept constant during the strengthening process. The results show that both the preexisting damage level and the FRP orientation have a significant effect on strengthening effectiveness and failure mode. All of the strengthened specimens exhibited higher capacities with capacity enhancements ranging from 21.8 to 66.4%, and the crack width reduced by 25.6-82.7% at failure load compared to the control beam. Finally, the authors present a comparison between the experimental results and the predictions using the ACI 440.2R-08 guidelines.

• Korean Journal of Health Education and Promotion
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• v.19 no.1
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• pp.45-58
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• 2002

This research was conducted to understand and analyze the physical awareness symptoms of college students and get fundamental research data essential to provide efficient student guidance and public health service at schools. The survey was carried out for 1 month from May 7th, 2001 to June 7th, 2001. The interviewees were 950 enrolled students at junior colleges in Daegu. 26.5% of them were men and 73.5% women. Among the surveyed, public health majors were 76.9%. Daytime students were 64.1 %, and the majority of the students, 42.8%, were atheistic. 56.0% of the students grew up in big cities, 22.2% in medium and small-sized cities, and 21.8% in farming and fishing communities. 66.1 % used public transportation. The majority of the students, 48.7%, answered that the satisfaction level for their majors was average. The result shows that the ocular fatigue was indicated as a greatest complaint, and the female students showed the higher complaint rate than the males. In the study of the complaining rate of physical symptoms by major, the public health majors showed the highest complaining rate in gasping when going up/down stairs, shoulder pain, a burning feeling on empty stomach, and leg/knee pain. On the other hand, the highest complaint factors for the technical majors were ocular fatigue and the feelings of heavy head. In the study of the complaining rate of physical symptoms by transportation, gasping during going up/down stairs and shoulder pain were most common, which were 52.2% and 36.0% respectively. In the study of the insecurity response distribution by transportation, college students who drive a car showed 3.8% and students using public transportation 3.7%. In the study of the insecurity response by subject satisfaction, students who answered dissatisfactory were 8.3%, average 3.9%, satisfied 3.0%. Therefore, it was concluded that students who were dissatisfied with their subjects showed the higher rate of insecurity response. it can be recommended that a school health education program regarding ocular fatigue and shoulder pain should be developed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.851-853
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• 2013

Recently, location-based service as the developed continuously, interest in positioning technology is increasing. As the most famous indoor positioning technology, WPS is a positioning technology using WiFi, which can complement the limits of the indoor positioning to have a GPS. In this paper, to provide a system for monitoring the position of the inside of the user based on the position information that using the RSSI signal of the wireless AP based WPS technology, they grip the location information of the mobile nodes in the indoor. If using the method proposed, it is expected to be applied to various services it is possible to apply the WPS, this is because it is possible to estimate in real time the location distribution of mobile nodes in the indoor.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.1
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• pp.205-213
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• 2011

The Long Term Evolution (LTE) system is designed to provide a high quality data service for fast moving mobile users. It is based on the Orthogonal Frequency Division Multiplexing (OFDM) and relies its channel estimation on the training samples which are systematically built within the transmitting data. Either a preamble or a lattice type is used for the distribution of training samples and the latter suits better for the multipath fading channel environment whose channel frequency response (CFR) fluctuates rapidly with time. In the lattice-type structure, the estimation of the CFR makes use of the least squares estimate (LSE) for each pilot samples, followed by an interpolation both in time-and in frequency-domain to fill up the channel estimates for subcarriers corresponding to data samples. All interpolation schemes should rely on the pilot estimates only, and thus, their performances are bounded by the quality of pilot estimates. However, the additive noise give rise to high fluctuation on the pilot estimates, especially in a communication environment with low signal-to-noise ratio. These high fluctuations could be monitored in the alternating high values of the first forward differences (FFD) between pilot estimates. In this paper, we analyzed statistically those FFD values and propose a postprocessing algorithm to suppress high fluctuations in the noisy pilot estimates. The proposed method is based on a localized adaptive moving-average filtering. The performance of the proposed technique is verified on a multipath environment suggested on a 3GPP LTE specification. It is shown that the mean-squared error (MSE) between the actual CFR and pilot estimates could be reduced up to 68% from the noisy pilot estimates.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.237-242
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• 2014

Recently, wind energy is expanding to combination of computing to forecast of wind power generation as well as intelligent of wind powerturbine. Wind power is rise and fall depending on weather conditions and difficult to predict the output for efficient power production. Wind power is need to reliably linked technology in order to efficient power generation. In this paper, distributed power generation forecasts to enhance the predicted and actual power generation in order to minimize the difference between the power of distributed power short-term prediction model is designed. The proposed model for prediction of short-term combining the physical models and statistical models were produced in a physical model of the predicted value predicted by the lattice points within the branch prediction to extract the value of a physical model by applying the estimated value of a statistical model for estimating power generation final gas phase produces a predicted value. Also, the proposed model in real-time National Weather Service forecast for medium-term and real-time observations used as input data to perform the short-term prediction models.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.211-218
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• 2014

Recently, wind energy is expanding to combination of computing to forecast of wind power generation as well as intelligent of wind powerturbine. Wind power is rise and fall depending on weather conditions and difficult to predict the output for efficient power production. Wind power is need to reliably linked technology in order to efficient power generation. In this paper, distributed power generation forecasts to enhance the predicted and actual power generation in order to minimize the difference between the power of distributed power short-term prediction model is designed. The proposed model for prediction of short-term combining the physical models and statistical models were produced in a physical model of the predicted value predicted by the lattice points within the branch prediction to extract the value of a physical model by applying the estimated value of a statistical model for estimating power generation final gas phase produces a predicted value. Also, the proposed model in real-time National Weather Service forecast for medium-term and real-time observations used as input data to perform the short-term prediction models.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.331-342
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• 2012

The effects of number of host plants and nectar plants on the number and diversity of butterflies were monitored and analyzed by simple and multiple regression from May 2008 to Sep 2009 in the Bubjusa region (Mt. Sokri, Boeun-gun, Chungcheongbuk-do), which was divided into four regions. The results demonstrate that the number of butterflies has a positive correlation with the number of host plant species, the number of nectar plant species, and the number of host plants multiple regression analysis. The number of butterflies also increased habitat area. However, the butterfly species number and diversity index showed lower correlation with the number of host plants and the area size of the divided region, respectively, when analyzed by simple regression. In addition, increased species diversity in a region with more diverse plant flora. These results suggest that the composite distribution of host and nectar plants with diverse plant flora is required for butterfly diversity and population preservation. Additionally, it also suggest that vegetation types complementarity all factors.