• Journal of the Korean earth science society
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• v.36 no.6
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• pp.543-552
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• 2015

This study examines the processes of rock weathering and tafoni formation targeting tafoni at Mt. Cheonsaeng, Gumi-si, Gyeongsangbuk-do. In the study area, a frequency of tafoni is high in conglomerate and conglomeratic sandstone among regional sedimentary rocks, which means that an initial stage of the formation begins a breakaway of gravel from bedrock and also exfoliation from rock surface. Geomorphologically tafoni have intensively been developed at the southfacing slope with exposed rocks, which means that its formation was favorably controlled by environmental conditions including strong influences of mechanical weathering in winter and chemical weathering in summer times. The results of measuring water content at a tafoni-bearing rock surface using GIS interpolation analysis indicate that moisture rate in/around tafoni is higher than the periphery. Thus, it is considered that moisture distribution at a rock surface plays a role in its formation. Analysis of percipitation and secondary minerals induced by chemical weathering is in progress.

• The Korean Journal of Pain
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• v.32 no.2
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• pp.120-128
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• 2019

Background: We aimed to explore the American College of Rheumatology (ACR) 1990 and 2011 fibromyalgia (FM) classification criteria's items and the components of Fibromyalgia Impact Questionnaire (FIQ) to identify features best discriminating FM features. Finally, we developed a combined FM diagnostic (C-FM) model using the FM's key features. Methods: The means and frequency on tender points (TPs), ACR 2011 components and FIQ items were calculated in the FM and non-FM (osteoarthritis [OA] and non-OA) patients. Then, two-step multiple logistic regression analysis was performed to order these variables according to their maximal statistical contribution in predicting group membership. Partial correlations assessed their unique contribution, and two-group discriminant analysis provided a classification table. Using receiver operator characteristic analyses, we determined the sensitivity and specificity of the final model. Results: A total of 172 patients with FM, 75 with OA and 21 with periarthritis or regional pain syndromes were enrolled. Two steps multiple logistic regression analysis identified 8 key features of FM which accounted for 64.8% of variance associated with FM group membership: lateral epicondyle TP with variance percentages (36.9%), neck pain (14.5%), fatigue (4.7%), insomnia (3%), upper back pain (2.2%), shoulder pain (1.5%), gluteal TP (1.2%), and FIQ fatigue (0.9%). The C-FM model demonstrated a 91.4% correct classification rate, 91.9% for sensitivity and 91.7% for specificity. Conclusions: The C-FM model can accurately detect FM patients among other pain disorders. Re-inclusion of TPs along with saving of FM main symptoms in the C-FM model is a unique feature of this model.

• Journal of The Geomorphological Association of Korea
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• v.26 no.3
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• pp.53-67
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• 2019

The purpose of this study is to identify the quality of landslide susceptibility in a landslide-prone area (Jinbu-myeon, Gangwon-do, South Korea) by spatial prediction modeling approach and compare the results obtained. For this goal, a landslide inventory map was prepared mainly based on past historical information and aerial photographs analysis (Daum Map, 2008), as well as some field observation. Altogether, 550 landslides were counted at the whole study area. Among them, 182 landslides are debris flow and each group of landslides was constructed in the inventory map separately. Then, the landslide inventory was randomly selected through Excel; 50% landslide was used for model analysis and the remaining 50% was used for validation purpose. Total 12 contributing factors, such as slope, aspect, curvature, topographic wetness index (TWI), elevation, forest type, forest timber diameter, forest crown density, geology, landuse, soil depth, and soil drainage were used in the analysis. Moreover, to find out the co-relation between landslide causative factors and incidents landslide, pixels were divided into several classes and frequency ratio for individual class was extracted. Eventually, six landslide susceptibility maps were constructed using the Bayesian Predictive Discriminant (BPD), Empirical Likelihood Ratio (ELR), and Linear Regression Method (LRM) models based on different category dada. Finally, in the cross validation process, landslide susceptibility map was plotted with a receiver operating characteristic (ROC) curve and calculated the area under the curve (AUC) and tried to extract success rate curve. The result showed that Bayesian, likelihood and linear models were of 85.52%, 85.23%, and 83.49% accuracy respectively for total data. Subsequently, in the category of debris flow landslide, results are little better compare with total data and its contained 86.33%, 85.53% and 84.17% accuracy. It means all three models were reasonable methods for landslide susceptibility analysis. The models have proved to produce reliable predictions for regional spatial planning or land-use planning.

• Geophysics and Geophysical Exploration
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• v.15 no.2
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• pp.51-56
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• 2012

One of the most critical and essential procedures in the interpretation of gravity and magnetic data is to separate the anomaly due to the specific geologic structure from the summation of effects from a broad variety of geologic sources, especially those of different depths. Separation of the residual anomaly from the regional field is the most simple case of the vertical separation. If the anomaly due to a layer of specific depth can be separated or the depth of the separated layer can be quantitatively determined, it may deserve the separation-sounding. We suggest a wavelength filter whose cutoff frequency is determined by log-power spectrum analysis, as a separation-sounding filter. We applied this filter both to synthetic and real gravity data acquired at Heunghae area, and compared the results with those of Jacobsen's upward continuation filter. These showed that the proposed separation-sounding filter could be a useful tool for interpretation of the vertical geologic structure by stripping the gravity effects of geologic sources down to the desired depth.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.458-471
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• 2020

Purpose: In Korea, the frequency and frequency of earthquakes are increasing every year. Therefore, the purpose of this study was to compare and analyze the characteristics and examples of earthquakes in Korea and Japan, and to propose improvements to the earthquake prevention policy in Korea. Method: In this study, we investigate and evaluate Japan's response in two cases: the Kobe earthquake and the East Japan earthquake. After surveying and evaluating the nation's countermeasures in the two events, Gyeongju and Pohang, they were compared. Result: When comparing recovery systems in Korea and Japan, there were significant differences in plans for restoration of road transport networks, regional disaster prevention plans, and the introduction of Conclusion: considering the physical distance between Korea's earthquake-prone areas and the capital, the government should quickly come up with countermeasures to ensure that immediate earthquake response in the region is enhanced through the detailed establishment of the Functional Continuity Plan (COOP), and that administrative functions will function normally in the event of a disaster through the introduction of the administrative BCP concept.

• Journal of Korean Academy of Nursing
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• v.12 no.2
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• pp.45-56
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• 1982

This study was carried out during the month of september 1982 to analyse and evaluate of the mental and physical health status of University woman students using the Cornell Medical index. The purpose of the study was to provide basic data required by the University health program for planning related health need of woman students. The study sample is consisted of 486 students living in the dormitory enrolled for the fall semester 1982 in a Women's University in Seoul. The instrument used for the collection of data was an abridged version of a modified Cornell Medical Index. The questionarre includes 35 items related to physical health complaints and 22 items related to mental health complaints. The data was treated by a computer(SPSS) using one way analysis, and The Fishers' ratio and Chi-square test at the 5％ level were also adjusted for the test for statistical significance. The interpretation of this study is limited due to the sample which was restricted to one University and not randomly selected. The followings are the results of the foundings so far achieved. 1. More than 60% of the Woman students have physical health problems in digestive system, cardiovascular system, nervous system, respiratory system, and musculo skeletal system in the order named. 2. More than 50% of the woman students have mental problems because of anger inadequacy sensitivity tension, depression and anxiety in the order named. 3. There were no statistically significant differences among woman students in mental and physical health problems caused by year groups, major groups, growing regional groups. 4. There were significant differences caused by the number of brothers and sisters in the aspect of appealing mental and physical problems. 5. There were significant differences caused by the rate of satisfaction in the living cost, and the lower the rate of the satisfaction in the living cost goes, the higher tile frequency rate of the appealing mental and physical health problems is. 6. There were significant differences caused by the rate of satisfaction of the living in the aspect of appealing mental and physical health problems. There fore, the lower the rate of the satisfaction of the living goes, the higher the frequency rate of the appealing mental and physical health problems is, and the more the complaints are, the more frequent the appealing of the problems of digestive system, circulating system and fatigue is.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2C
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• pp.238-245
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• 2010

For orthogonal frequency division multiplexing (OFDM) systems sharing the spectrum with narrow band primary devices, a fractional bandwidth (FBW) mode has been proposed recently to reduce the interference to the primary users. The FBW mode divides the total OFDM bandwidth into subbands and activates (or deactivates) a subset of the subbands according to the result of spectrum sensing. In this paper, we analyze the detection error probability of FBW mode information which is delivered by the sequence embedded in the preamble and evaluate the performance in wireless regional area network environments. The results show that the detection probability derived analytically estimates the actual value from simulation adequately and that a low detection error probability less than $10^{-3}$ is obtained at a low signal-to-noise power ratio.

• Journal of Korean Society of Transportation
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• v.25 no.5
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• pp.111-122
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• 2007

This paper investigates the rail service patterns by train class. The emphasis in intercity rail planning is to more efficiently use of existing station facilities. Rail transit operations are affected by the system layout and ridership patterns and by work rules. Operations are also influenced by past practices and the institutional setting. Main factors to decide train service patterns are the location, socioeconomic characteristics, land use and travel demand of the station. In this context, the travel demand of intercity rail station is of crucial significance. Tests on a KTX case shows that train service frequency can be efficiently decreased in weekday to transport the same passenger demand. The work has shown many subjects that need further research including various factors influencing on train frequency. This study serves the railroad authorities in planning and determining business strategy in the increasingly competitive environment of regional rail transport.

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.3
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• pp.77-88
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• 2019

Drought is the recurrent natural disasters which harshly affect agricultural production and society in various parts in Bangladesh. Information on the spatiotemporal variability of drought events plays a vital role to take necessary action towards drought mitigation and sustainable development. This study aims to analyze the spatial and temporal variation of meteorological drought in Bangladesh during 1981-2015 using Effective Drought Index (EDI). Monthly precipitation data for 36 years (1980-2015) were obtained from 27 meteorological stations. Drought frequency (DF) and areal extent of drought were considered to investigate the spatiotemporal structure of drought. The DF analysis showed that the northern, southwestern and central regions of the country are comparatively vulnerable to meteorological drought. The frequency of drought in all categories has considerably increased during the recent five years from 2011 to 2015. Furthermore, the most significant increasing trend of the drought-affected area was found over the central region especially for pre-monsoon (March-May) season during this period while the decreasing trend of the affected area was found within the eastern region during the study period. To prevent and mitigate the damages of drought disasters in Bangladesh, agricultural and government managers should pay more attention to those regional drought events that occur in pre-monsoon season. The outcome of the present study can be used as explanatory data in building the strategies to drought monitoring and mitigation activities in Bangladesh.

• Journal of the Korean Geotechnical Society
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• v.35 no.11
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• pp.121-129
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• 2019

An Earthquake Early Warning (EEW) system is a technology that alerts people to an incoming earthquake by using P waves that are detected before the arrival of more severe seismic waves. P-wave analysis is therefore an important factor in the production of rapid seismic information as it can be used to quickly estimate the earthquake magnitude and epicenter through the amplitude and predominant period of the observed P-wave. However, when a large-magnitude teleseismic earthquake is observed in a local seismic network, the significantly attenuated P wave phases may be mischaracterized as belonging to a small-magnitude local earthquake in the initial analysis stage. Such a misanalysis may be sent to the public as a false alert, reducing the credibility of the EEW system and potentially causing economic losses for infrastructure and industrial facilities. Therefore, it is necessary to develop methods that reduce misanalysis. In this study, the possibility of seismic misclassifying teleseimic earthquakes as local events was reviewed using the Filter Bank method, which uses the attenuation characteristics of P waves to classify local and outside Korean peninsula (regional and teleseismic) events with filtered waveform depending on frequency and epicenter distance. The data used in our analysis were analyzed for maximum P_v values using 463 events with local magnitudes (2 < M_L ≦ 3), 44 (3 < M_L ≦ 4), 4 (4 < M_L ≦ 5), 3 (M_L > 5), and 89 outside Korean peninsula earthquakes recorded by the KMA seismic network. The results show that local and telesesimic earthquakes can be classified more accurately when combination of filtering bands of No. 3 (6-12 Hz) and No. 6 (0.75-1.5 Hz) is applied.