• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.55-63
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• 2020

Road traffic noise is a major complaint. Porous pavement (PP) has been proposed as an effective method for reducing road traffic noise, but it has not been applied much due to the lack of quantitative evaluation. In this study, the noise reduction of single-layer porous pavement (SLPP) and double-layer porous pavement (DLPP) was evaluated. The noise was measured using the CPX method, and the driving speed was measured every 10km/h from 50km/h to 80km/h. The differences in noise level between the two PPs were statistically significant. The driving speed had no significant effect on the difference in noise between the two PPs. The DLPP showed a 6.6dB(A) reduction in average and a 6.3dB(A) reduction at the 95% confidence level compared to the SLPP. Reducing noise by 5dB(A) is equivalent to reducing traffic to 1/3 or lowering the vehicle's speed to 1/2. Sensitively, it is possible to recognize a 3dB(A) and 5dB(A) difference. The DLPP and SLPP were very effective in reducing traffic noise.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.175-182
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• 2021

As road noise became an issue, low-noise pavement (LNP) has emerged. The noise difference from general asphalt pavement (GAP) is a measure to explain the noise reduction of LNP. On the other hand, even for GAP, noise varies with the performance years (PY) and pavement condition. This study evaluated the representative noise value (RNV) by the speed and PY of GAP. Sections of 49selected from the National Road Pavement Management System, and the noise was measured at speeds from 50km/h to 80km/h at every 10km/h using the Close Proximity Method (CPX). Because the noise immediately after construction differed from the other, it was treated separately, and some outliers were removed. The noise increased with increasing PY. In addition, the noise increase by speed showed a reliable trend at all noise levels. The RNV for each speed and PY was obtained through analyses of the PY and speed. The average noise difference between the initial construction and the six-year-paced pavement was approximately 6dB. When evaluating the noise reduction of LNP, it is necessary to use RNV rather than the noise of old pavement. The RNV of GAP is necessary for a relative comparison with LNP and studying the road noise characteristics for each GAP type.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.6
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• pp.27-33
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• 2014

2nd stage of KSLV-I, NaRo-Ho, performs CCAM not to collide with Naro Science Satellite. At that moment, the satellite should pass through the Plume Density area which was generated by KSLV-I KM residual thrust. Therefore, it is necessary to predict Plume Density field of KM residual thrust and guarantee the safety of the trajectory of payload. In this paper, DSMC method was used to simulate Plume Density by KM residual thrust and the simulation showed that the trajectory of Naro Science Satellite was safe.

• Journal of Environmental Impact Assessment
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• v.22 no.6
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• pp.557-568
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• 2013

In this study, Calculated the nonpoint sources(NPS) load per unit area about various rainy events in vineyard of Nakdong River basin. NPS monitoring and calculation for NPS load per unit area were estimated from 'Investigation method of precipitation discharge(National Institute of Environmental Research, 2007)'. The evaluation of applicability for NPS load per unit by compared with prior research data and Total Maximum Daily Load(TMDL) data. Five target areas were each $2000m^2$, $1800m^2$, $1943m^2$, $2484m^2$, $864m^2$ and located in Gyeongsangbukdo Gyeongju, Gyeongsangbukdo Sangju, Gyeongsangnamdo Hapcheon in Korea. Since fruits were the only crop on the target area, the characteristics of stormwater discharge at survey sites could be evaluated independently. A total of 115 rainfall events in the Orchard area during five years(2008-2012) was surveyed, and 38 of them became stormwater discharge. In the Nakdong River watershed, average of event mean concentrations(EMCs) in Orchard area for biochemical oxyzen demand(BOD), Chemical oxyzen demand(COD), total nitrogen(T-N), total phosphorus(T-P) were 2.0mg/L, 10.1mg/L, 3.195mg/L, 0.578mg/L, respectively. NPS load per unit area in Orchard area showed BOD : $2.0kg/km^2{\cdot}day$, COD : $10.2kg/km^2{\cdot}day$, T-N : $3.220kg/km^2{\cdot}day$, T-P : $0.606kg/km^2{\cdot}day$.

• Atmosphere
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• v.22 no.1
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• pp.1-12
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• 2012

The Atmospheric motion vectors (AMVs) derived using infrared (IR) channel imagery of geostationary satellites have been utilized widely for real-time weather analysis and data assimilation into global numerical prediction model. As the horizontal resolution of sensors on-board satellites gets higher, it becomes possible to identify atmospheric motions induced by convective clouds ($meso-{\beta}$ and $meso-{\gamma}$ scales). The National Institute of Meteorological Research (NIMR) developed the high resolution visible (HRV) AMV algorithm to detect mesoscale atmospheric motions including ageostrophic flows. To retrieve atmospheric motions smaller than $meso-{\beta}$ scale effectively, the target size is reduced and the visible channel imagery of geostationary satellite with 1 km resolution is used. For the accurate AMVs, optimal conditions are decided by investigating sensitivity of algorithm to target selection and correction method of height assignment. The results show that the optimal conditions are target size of 32 km ${\times}$ 32 km, the grid interval as same as target size, and the optimal target selection method. The HRV AMVs derived with these conditions depict more effectively tropical cyclone OMAIS than IR AMVs and the mean speed of HRV AMVs in OMAIS is slightly faster than that of IR AMVs. Optimized mesoscale AMVs are derived for 6 months (Feb. 2010-Jun. 2010) and validated with radiosonde observations, which indicates NIMR's HRV AMV algorithm can retrieve successfully mesoscale atmospheric motions.

• Journal of Korean Society of Forest Science
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• v.84 no.3
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• pp.319-332
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• 1995

This research was carried out to investigate the influences of forest road characteristics and rainfalls on the amount of erosion on the newly - constructed forest road in the Research Forests of Seoul National University located in Mt. Backwoon - san, Kwangyang. Amount of soil erosion on the newly - constructed forest road was measured for 2 years since the forest road construction. Using the stepwise multiple regression method, amount of soil erosion from cut - slopes, fill - slopes, road surfaces, and side - ditches were seperately expressed as a function of statistically significant road design and rainfall factors, and multiple regression models to estimate the amount of soil erosion were significant to explain the variance in erosion by each structures. According to results of this study, amount of erosion from the newly - constructed forest road was estimated as much as 668.51m/km for 2 years. Out of total amount of soil erosion, 21.9%(144.27m/km) from cut - slopes, 39.8%(261.89m/km) from fill - slopes, 8.1%(53.33m/km) from road surfaces, and 30.2%(199.02m/km) from side - ditches were occurred.

• The Journal of Korean Obstetrics and Gynecology
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• v.20 no.4
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• pp.175-190
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• 2007

Purpose: Ovarian cysts are fluid-filled sacs or pockets within or on the surface of an ovary. Most cysts present little or no discomfort and are noncancerous and harmless. So non-surgical treatments with herbal medicine or acupuncture and moxa therapy are important and suitable in this pathology. But there are few RCT articles about ovarian cyst in Korean Medicine(KM) clinical and research field. Methods: To review treatment method and other research tendency about ovarian cyst in journals related with KM and Traditional Chinese Medicine(TCM) through web-searching. Searching was done through web site #http://omis.ksucc.ac.kr# and pub-med(http://www.ncbi.nlm.nih.gov/sites/entrez) with key words #ovarian cyst#, #TCM#, #herb#, #CAM#, and #acupuncture#. Results: Seven articles were searched in journals related with KM, then six of them were simple case report and the other one was about diagnosis for ovarian cyst and another gynecologic disease such as uterine myoma and infertility through the iris diagnosis. And two articles were searched in journals related with TCM, then one of them was simple case report but the other is RCT article. Conclusion: KM and TCM therapies have some beneficial effect to resolve cyst, but objective power as a evidence is weak in the viewpoint of EBM. So continuous clinical trials such as RCT and multi center trials are needed.

• The Journal of Korean Obstetrics and Gynecology
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• v.21 no.1
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• pp.134-149
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• 2008

Purpose: Dysmenorrhea is a common gynecologic condition among reproductive-age women. It consisted with menstrual clamps and other symptoms such as nausea. vomiting, diarrhea, and fatigue. Pain control for this disease mainly through NASIDs. but recently CAM therapies, acupuncture and others for painful menstruation are widely used in western countries. But RCT articles about dysmenorrhea in Korea, are not enough to lead such global research trends. The purpose of this study is to review treatment method and other research tendency about dysmenorrhea in Korean Medicine(KM) related dominant journals. Methods: Searching was done through web site and directly searched dysmenorrhea related articles in journals of Korean medicine Gynecology, published during 1996-2007. Results: Twenty five articles were searched in KM related journals, then two of them were simple case report and ten were paper of clinical trials. But there no RCT or control group-designed study. All of them present positive effect on dysmenorrhea but drop out rates were relatively high. Conclusion: KM therapies including acupuncture and herbal medicine have some beneficial effect to resolve menstrual cramps, but KM therapy related Korean articles don't have strong objective power as a evidence in the viewpoint of EBM. So continuous clinical trials such as RCT and multi center trials are needed.

• The Journal of Korean Medicine
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• v.37 no.3
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• pp.112-122
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• 2016

Objectives: This study aimed to assess the validity of 'Korean Diagnosis Related Groups-Korean Medicine (KDRG-KM)' which was developed by Health Insurance Review & Assessment Service (HIRA) in 2013 Methods: Among inpatient EDI claim data issued by hospitals and clinics in 2012, the data which included Korean medicine procedures were selected and analyzed. We selected control targets in the Korean medicine hospitals which had longer Episodes-Costliness index (ECI) and Lengthiness index (LI) than average of total Korean medicine hospitals, and compared the results of selection between the major diagnosis-based patient classification system and the KDRG-KM system. Finally, the explanation power (R2) and coefficient of variation (CV) of the KDRG-KM system using practice expenses were calculated. Results: The numbers of control target in Korean medicine hospitals changed from 36 to 32 when patient grouping adjustment method was changed from major diagnosis to KDRG-KM. For expenses of all outpatient claim data on Korean medicine, explanation power of KDRG-KM system was 66.48% after excluding outliers. CVs of expenses of patient groups in Korean medicine hospitals were gathered from under 70% to under 90%, and those in long-term care hospitals mostly belonged under 70%. Conclusions: The validity of KDRG-KM system was assured in terms of explanation power. By adapting KDRG-KM system, fairness of control targets selection for costliness management in Korean medicine hospitals can be enhanced.

• Geophysics and Geophysical Exploration
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• v.21 no.1
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• pp.26-32
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• 2018

The Northeast China is an important site geologically and geophysically because of a huge volcano called Mt. Baekdu, which is one of the largest volcanoes in the world. Signs of eruption have been recently observed and people are keen to its behavior. We carried out relative travel time tomography to investigate the velocity structure between 100 ~ 600 km depth beneath Northeast China. We used teleseismic data during 2009 ~ 2011 recorded in NecessArray provided by IRIS (Incorporated Research Institute for Seismology). The relative observations were obtained by using the multi-channel cross-correlation method. Based on the tomographic results, we observed that the locations beneath which low-velocity zones are observed coincide with the locations of several volcanic regions in Northeast China. A low-velocity anomaly is revealed beneath Mt. Baekdu down to 600 km depth, which is thought to the main origin of the magma supply for Mt. Baekdu. Another low velocity anomaly is observed beneath east of the Datong volcano down to around 300 km depth, which is inferred to be related to an upwelling from deep mantle. We observed a low velocity anomaly beneath the Wudalianchi volcano down to around 200 km depth, which may imply that this volcano has been formed by an upwelling from the asthenosphere.