• Explosives and Blasting
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• v.30 no.2
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• pp.21-28
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• 2012

Blasting methods are frequently used in case of forming slope artificially like slope cutting and open-cut method in the downtown area because of many economical and effective advantages. It is important that blasting work is carried out maintaining original strength of rock and not to damage rock face. And it is also considered that blasting method to decrease ground vibration is essential to the point of blast damages due to the ground vibration. In this study, to form a smooth plane of rock slope face, many trial blasts were carried out in this way that explosives were installed in detonating cord by equal interval in different charging method and stemming method. Using 4 blasting patterns in total 60 blast holes and 20 times of blasts were carried out. At the same time ground vibration measurements were carried out 15~102m away from the blast source, and total number of 310 data were obtained. Measured data for ground vibration velocity were analyzed so as to study blasting method to protect slope plane while decreasing blast vibration in an effective way.

• Journal of Advanced Navigation Technology
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• v.10 no.2
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• pp.173-180
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• 2006

An airborne radar is an essential aviation electronic system of the aircraft to perform various missions in all weather environments. This paper presents the design, development, and test results of the multi-mode pulsed Doppler radar system test model for helicopter-borne flight test. This radar system consists of 4 LRU units, which include ANTU(Antenna Unit), TRU(Tx Rx Unit), RSDU(Radar Signal & Data Processing Unit) and DISU(Display Unit). The developed technologies include the TACCAR processor, planar array antenna, TWTA transmitter, coherent I/Q detector, digital pulse compression, DSP based Doppler FFT filtering, adaptive CFAR, IMU, and tracking capability. The design performance of the developed radar system is verified through various helicopter-borne field tests including MTD (Moving Target Detector) capability for the Doppler compensation due to the moving platform motion.

• Journal of Environmental Impact Assessment
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• v.24 no.3
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• pp.244-259
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• 2015

The Strategic Environmental Impact Assessment(SEIA) in Korea has been introduced and implemented for 15 policy-level plans and 86 project-level plans since 2012. Lately an important issue of the Environmental Impact Assessment(EIA) policy has been emerged regarding the expansion of the policy-level plans subjected to SEIA. Thus, we propose the plans that need to be included in the system, compared with those subjected to the Strategic Environmental Assessment(SEA) enforced in the law or the guideline of 10 foreign counties, especially with those of Germany, France, Italy, the United Kingdom, and Netherlands. Specifically the study suggests that plans related to energy as well as land use, which are well known to cause potential environmental impacts and subjected to the federal-level SEA in those countries, should be the subject of SEIA.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.85-92
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• 2015

It is well known that axial tension decreases the shear strength of RC & PSC beams without transverse reinforcement, and axial compression increases the shear resistance. What is perhaps not very well understood is how much the shear resistance capacity is influenced by axial load. RC beams without shear reinforcement subjected to large axial compression and shear may fail in a very brittle manner at the instance of first diagonal cracking. As a result, a conservative approach should be used for such members. According to the ACI Code, the shear strength in web is calculated by effect of axial force and the vertical force in the stirrups calculated by $45^{\circ}$ truss model. This study was performed to examine the effect of axial force in reinforced concrete beams by nonlinear FEM program (ATENA-2D).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.101-110
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• 2015

Recently, nine $1397{\times}1397{\times}178mm$ RC panels were tested under in-plane pure-shear monotonic loading condition using the Panel Element Tester by Hsu (1997, ACI). By combining the equilibrium, compatibility, and the softened stress-strain relationship of concrete in biaxial state, Modern Truss Model (MCFT, RA-STM) are capable of producing the nonlinear analysis of RC membrane panel through the complicated trial-and-error method with double loop. In this paper, an efficient algorithm with one loop is proposed for the refined Mohr compatibility Method based on the strut-tie failure criteria. This algorithm can be speedy calculated to analyze the shear history of RC membrane element using the results of Hsu test. The results indicate that the response of shear deformation energy at Big Bang of shear strain significantly influenced by the principal compressive stress-strain (crushing failure).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3232-3237
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• 2013

This study was carried out to evaluate the economic value of Tyvek planting technique in Korean citrus. The Tyvek planting technique was developed by national institute of horticultural and herbal science in Korea rural development administration. This technology could be used to improve efficiency and practicality of cultivation of citrus. The research results show that the technological value of Tyvek planting technique was evaluated 42,163(discount rate 6%)-55,018(discount rate 8%) million won. IRR is greater than discount rate(6-10%). NPV is greater than zero. B/C ratio IRR is greater than 20. The economic validity of Tyvek planting technique is identified by the results of technology evaluation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.1
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• pp.44-56
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• 2007

The flora was summarized as 195 taxa; 73 families, 138 genera, 168 species, 23 varieties and 4 forms in Jangsoo-ri windbreak forest and 151 taxa; 63 families, 118 genera, 131 species, 18 varieties and 2 forms in Pyeongsa-ri windbreak forest. Based on the list of the rare plants by the Forest Research Institute, 3 taxa and based on the list of Korean endemic plant 4 taxa were recorded in the studied areas; Puccinellia coreensis (Gramineae), Asarum maculatum (Aristolochiaceae), Prunus yedoensis (Rosaceae), Koelreuteria paniculata (Sapindaceae), Adenophora triphylla var. hirsuta (Campanulaceae). The Specific Plant Species which is categorized by the Ministry of Environment, Korea, was summarized as 23 taxa for the 1 degree of 17 taxa, 3 degree of 5 taxa, 5 degree of 1 taxa in Jangsoo-ri windbreak forest and 22 taxa for the 1 degree of 18 taxa, 3 degree of 3 taxa, 5 degree of 1 taxa in Pyeongsa-ri windbreak forest. From the enlisted the flora surveyed, the naturalized plants were 17 taxa in Jangsoo-ri windbreak forest and 19 taxa in Pyeongsa-ri windbreak forests with the Naturalization rate was 8.7 percent and 12.6 percent, respectively. In Jangsoo-ri windbreak forest, there has been occurred many man-made impair and development without legal institution and control. So, it needs in haste institutional conservation measures and systemic database construction about function and necessity of windbreak forest. In Pyeongsa-ri windbreak forest, recently many people visited here. So, if we make eco-tour place connecting nearby coast and windbreak forest, it will contribute resident's economic profit and opportunity, concerns about windbreak forest, and necessity of conservation measures. Recently, the windbreak forests in Jangsoo-ri and Pyeongsa-ri should be bereaved windbreak forest of function by the human activities.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.488-494
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• 2001

This study was conducted to investigate forest ecosystem assessment which were widely used in Germany and Austria. The study area, Mt. Teawha, is located at Kwangju, Kyunggi-Do province. The methodology of this study considered the following factors. First forest types were classified accoding to species composition and age of tree layer. Naturalness, diversity and rerenees of each forest type were classified into 5 level. Finally, the forest types were assessed by synthesizing those 3 factors. Qurecus mongolica- and valley forest type over 300m was classified as naturalness 4 and Qurecus accustima, Quercus accusitima and Q. variabilis were as naturalness 3. The plantation types on the lower slope showed the level of naturlness 1 or 2. Diversity was similer to naturalness. But indices were different from each other. In the case of Larix leptolepsis plantations, naturalness indicated 1, while diversity showed 3. The valley forest type, wet forest and forest edge were classified into rare forest type. It was concluded that this method could be more efficient method comparing with existing method for assessment of naturality and thereby could contribute for biodiversity conservation in Korea.

• Journal of the Korean Data and Information Science Society
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• v.23 no.5
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• pp.913-925
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• 2012

This study evaluates the economic benefit of the project constructing the international riding arena having been built at Sangju in Gyeongsangbuk-Do by the willingness to pay (WTP) of residents in the province. As the evaluation method, the dichotomous choice contingent valuation method (CVM) is adopted with the additional questions of whether his/her WTP is zero, to improve the statistical accuracy of evaluation results. Considering the arena's administrative location, the population of the surveys for analysis is confined to residents of Daegu and Gyeongsangbuk-do. The survey is conducted through personal interviews. It turns out that the WTP per household per year is evaluated as 1,847 won and the total yearly benefit of the Sangju international horse riding arena is estimated as 3.56 billion won.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.137.2-137.2
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• 2010

With current real economic growth of more than 10% per year, the Chinese energy consumption is rapidly increasing. Coal supply consists of the vast majority of China's total energy consumption requirements in 2008. China, the largest energy consumer, is expected to be heavily dependent on coal for future power generation, too (IEA,2009). A growing concern on global warming, on the other hand, drives Chinese government to declare her commitment to the reduction of CO2 emission by 2020. In this paper, China's energy market is examined for the current and future primary energy mix. Coal is found to be the biggest part accounting for 68.7% of total primary energy consumption while coal-fired power accounts for over 80% of the total power generation. The importance of Clean Coal Technology is being discussed based on the findings of the importance of coal in China's economy and its sustainable development. Among the technologies involved, a brief investigation of IGCC(Integrated Gasification Combined Cycle) technology with a review on current IGCC projects in China are provided from the perspective of environmental benefits. Studies on regional Chinese power market is also conducted. It is found that the regulated power tariff in electricity system makes the power suppliers suffer from financial loss and changes in the electricity price system is under serious consideration by Chinese government. Even though Chinese power market system causes difficulties of commercialization for IGCC technology, the potential benefits will be high due to China's huge requirements of power generating capacity and its heavy reliance on coal if the electricity price system can be changed smoothly.