• Journal of the Society of Disaster Information
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• v.17 no.4
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• pp.694-709
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• 2021

Purpose: In this study, earthquake-induced landslide risk assessment was conducted to provide basic data for efficient and preemptive damage prevention by selecting the erosion control work before the earthquake and the prediction and restoration priorities of the damaged area after the earthquake. Method: The study analyzed the previous studies abroad to examine the evaluation methodology and to derive the evaluation factors, and examine the utilization of the landslide hazard map currently used in Korea. In addition, the earthquake-induced landslide hazard map was also established on a pilot basis based on the fault zone and epicenter of Pohang using seismic attenuation. Result: The earthquake-induced landslide risk assessment study showed that China ranked 44%, Italy 16%, the U.S. 15%, Japan 10%, and Taiwan 8%. As for the evaluation method, the statistical model was the most common at 59%, and the physical model was found at 23%. The factors frequently used in the statistical model were altitude, distance from the fault, gradient, slope aspect, country rock, and topographic curvature. Since Korea's landslide hazard map reflects topography, geology, and forest floor conditions, it has been shown that it is reasonable to evaluate the risk of earthquake-induced landslides using it. As a result of evaluating the risk of landslides based on the fault zone and epicenter in the Pohang area, the risk grade was changed to reflect the impact of the earthquake. Conclusion: It is effective to use the landslide hazard map to evaluate the risk of earthquake-induced landslides at the regional scale. The risk map based on the fault zone is effective when used in the selection of a target site for preventive erosion control work to prevent damage from earthquake-induced landslides. In addition, the risk map based on the epicenter can be used for efficient follow-up management in order to prioritize damage prevention measures, such as to investigate the current status of landslide damage after an earthquake, or to restore the damaged area.

• 한국노년학
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• v.29 no.1
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• pp.329-352
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• 2009

This study examined life in old age and images of the aged perceived by middle-aged and old-aged generations through indepth interviews with 30 persons aged 40s through 80s residing in three areas (city or county) in capital region in Korea to use it as basic information in planning social welfare policy and reorganizing social services in response to population aging in capital region in Korea. In terms of economic life of the middle-aged and olde-aged generations perceived older people's opportunities for work were rarely given to the aged due to ageism and negative stereotypes of aging and the aged, and the aged tended to regard themselves less able or unable to work. In terms of social life of the aged both middle-aged and old-aged generations perceived that the frequency of social participation was low, and the daily life of the aged was found mostly aimless, unorganized and unplanned. In terms of psycho-social life of the aged both generations still felt that they were not alienated from the family, neighbors, and the society. In terms of social welfare services both generations thought the aged needed basic services such as income maintenance, health care, housing services, and particularly they felt lack of social services. The old-aged generation was willing to travel to the distance taking more than one hour to receive social services that they would need. Both the middle-aged and the old-aged agreed upon the necessity of preparation for old age and the benefits of earlier preparation, however, they said that they could not prepare for their old age due to lack of social programs to help preparation for old age and due to spending for rearing and education of their children. In terms of perceived life in old age both middle-aged and old-aged generations tended to be slightly positive, but the degree of positiveness differed between respondents from urban area and those from rural area regardless of generations. Images of the aged were perceived to be overwhelmingly negative while positive images were very few in number regardless of generations. This finding may suggests that negative stereotypes on aging and the aged are also prevalent in Korean society like in Western societies. Based on findings of this study some implications for social policies in response to population aging in capital region were suggested.

• Tuberculosis and Respiratory Diseases
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• v.43 no.5
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• pp.736-745
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• 1996

Background : It is known that pulmonary rehabilitation improves dyspnea and exercise tolerance in patient with chronic lung disease, although it does not improve pulmonary function. But there is a controversy whether this improvement after pulmonary rehabilitation is due to increased aerobic exercise capacity. We performed this study to evaluate the effect of pulmonary rehabilitation for 6 weeks on the pulmonary function, gas exchange, exercise tolerance and aerobic exercise capacity in patients with chronic lung disease. Methods : Pulmonary rehabilitations including education, muscle strengthening exercise and symptom-Umited aerobic exercise for six weeks, were performed in fourteen patients with chronic lung disease (COPD 11, bronchiectasis 1, IPF 1, sarcoidosis 1 ; mean age $57{\pm}4$ years; male 12, female 2). Pre- and post-rehabilitaion pulmonary function and exercise capacity were compared. Results: 1) Before the rehabilitation, FVC, $FEV_1$ and $FEF_{25-75%}$ of the patients were $71.5{\pm}6.4%$. $40.6{\pm}3.4%$ and $19.3{\pm}3.8%$ of predicted value respectively. TLC, FRC and RV were $130.3{\pm}9.3%$, $157.3{\pm}13.2%$ and $211.1{\pm}23.9%$ predicted respectively. Diffusing capacity and MVV were $59.1{\pm}1.1%$ and $48.6{\pm}6.2%$. These pulmonary functions did not change after pulmonary rehabilitation. 2) In the incremental exercise test using bicycle ergometer, maximum work rale ($57.7{\pm}4.9$) watts vs. $64.8{\pm}6.0$ watts, P=0.036), maximum oxygen consumption ($0.81{\pm}0.07$ L/min vs. $0.96{\mu}0.08$ L/min, P=0.009) and anaerobic threshold ($0.60{\pm}0.06$ L/min vs. $0.76{\mu}0.06$ L/min, P=0.009) were significantly increased after pulmonary rehabilitation. There was no improvement in gas exchange after rehabilitation. 3) Exercise endurances of upper ($4.5{\pm}0.7$ joule vs. $14.8{\pm}2.4$ joule, P<0.001) and lower extremity ($25.4{\pm}5.7$ joule vs. $42.6{\pm}7.7$ joule, P<0.001), and 6 minute walking distance ($392{\pm}35$ meter vs. $459{\pm}33$ meter, P<0.001) were significantly increased after rehabilitation. Maximum inspiratory pressure was also increased after rehabilitation ($68.5{\pm}5.4$ $CmH_2O$ VS. $80.4{\pm}6.4$ $CmH_2O$, P<0.001). Conclusion: The pulmonary rehabilitation for 6 weeks can improve exercise performance in patients with chronic lung disease.

• Journal of Intelligence and Information Systems
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• v.18 no.1
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• pp.1-21
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• 2012

In recent years, mobile phone has experienced an extremely fast evolution. It is equipped with high-quality color displays, high resolution cameras, and real-time accelerated 3D graphics. In addition, some other features are includes GPS sensor and Digital Compass, etc. This evolution advent significantly helps the application developers to use the power of smart-phones, to create a rich environment that offers a wide range of services and exciting possibilities. To date mobile AR in outdoor research there are many popular location-based AR services, such Layar and Wikitude. These systems have big limitation the AR contents hardly overlaid on the real target. Another research is context-based AR services using image recognition and tracking. The AR contents are precisely overlaid on the real target. But the real-time performance is restricted by the retrieval time and hardly implement in large scale area. In our work, we exploit to combine advantages of location-based AR with context-based AR. The system can easily find out surrounding landmarks first and then do the recognition and tracking with them. The proposed system mainly consists of two major parts-landmark browsing module and annotation module. In landmark browsing module, user can view an augmented virtual information (information media), such as text, picture and video on their smart-phone viewfinder, when they pointing out their smart-phone to a certain building or landmark. For this, landmark recognition technique is applied in this work. SURF point-based features are used in the matching process due to their robustness. To ensure the image retrieval and matching processes is fast enough for real time tracking, we exploit the contextual device (GPS and digital compass) information. This is necessary to select the nearest and pointed orientation landmarks from the database. The queried image is only matched with this selected data. Therefore, the speed for matching will be significantly increased. Secondly is the annotation module. Instead of viewing only the augmented information media, user can create virtual annotation based on linked data. Having to know a full knowledge about the landmark, are not necessary required. They can simply look for the appropriate topic by searching it with a keyword in linked data. With this, it helps the system to find out target URI in order to generate correct AR contents. On the other hand, in order to recognize target landmarks, images of selected building or landmark are captured from different angle and distance. This procedure looks like a similar processing of building a connection between the real building and the virtual information existed in the Linked Open Data. In our experiments, search range in the database is reduced by clustering images into groups according to their coordinates. A Grid-base clustering method and user location information are used to restrict the retrieval range. Comparing the existed research using cluster and GPS information the retrieval time is around 70~80ms. Experiment results show our approach the retrieval time reduces to around 18~20ms in average. Therefore the totally processing time is reduced from 490~540ms to 438~480ms. The performance improvement will be more obvious when the database growing. It demonstrates the proposed system is efficient and robust in many cases.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.4
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• pp.169-178
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• 1980

Ammonium nitrate explosion technique was applied to seek a convenient method for the establishment of orchard on the undulating to rolling land or hill side of Pogog clay loam soil (Fine Aquic Fragiudalfs : Planosols) having high bulk density and low permeability. Explosions were made by three ammonium nitrate explosives placed in the bottom of 90cm deep auger hole with every 2m interval (Explosion I) and 4m interval (Explosion II) respectively. The effect of the explosion on physical properties of the soil was investigated and compared with the effect induced by manual digging, excavation of $1m{\times}1m$ in diameter and depth (Manual digging I) and trenching of $1m{\times}1m{\times}25m$ in width, depth, and length (Manual digging II) respectively. The results investigated after 7 months from the treatments are summarized as follows : 1. The explosion or manual digging reduced bulk density and hardness, whereas the treatments increased porosity, hydraulic conductivity, and available moisture-holding capacity of the soil. 2. The explosion of 4 m interval improved physical properties of the soil to optimum level up to 70cm of the distance from the explosion core in the range of depth 0-60cm, while in the case of depth from 60 to 100cm the optimum level was achieved only within 50cm radius. 3. When exploded in 2 m interval, the effect in the 0-60cm depth was overlapped between two explosion cores. The effect in the depth between 60 and 100cm, however, was found to be independent of the explosion intervals. 4. The manual digging was only costly and laborious but effective only within the work-up zone. 5. For the soils having bulk density higher than $1.4g/cm^3$ after the treatments, the field capacity determined 72 hours after a heavy rain was lower than the laboratory estimate at the suction of 1/3 atm. 6. The top growth of apple tree for the first year revealed that the explosion seemed better treatment than the manual digging, even though the difference was insignificant.

• Economic and Environmental Geology
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• v.19 no.spc
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• pp.19-41
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• 1986

Structural, radioactive, petrological, petrochemical, mineralogical and stable isotopic study as well as the review of previous studies of the uranium-bearing slates in the Ogcheon sequence were carried out to examine the lithological and structural controls, and geochemical environment in the uranium deposition in the sequence. And the study was extended to the coal-bearing formation (Jangseong Series-Permian) to compare the geochemical and sedimentologic aspects of uranium chemistry between Ogcheon and Hambaegsan areas. The results obtained are as follows: 1. The uranium mineralization occurs in the carbonaceous black slates of the middle to lower Guryongsan formation and its equivalents in the Ogcheon sequence. In general, two or three uranium-bearing carbonaceous beds are found with about 1 to 1.5km stratigraphic interval and they extend from Chungju to Jinsan for 90km in distance, with intermittent igneous intrusions and structural Jisturbances. Average thickness of the beds ranges from 20 to 1,500m. 2. These carbonaceous slate beds were folded by a strong $F_1$-fold and were refolded by subsequent $F_1$-fold, nearly co-axial with the $F_1$, resulting in a repeated occurrence of similar slate. The carbonaceous beds were swelled in hing zones and were shrinked or thined out in limb by the these foldings. Minor faulting and brecciation of the carbonaceous beds were followed causing metamorphism of these beds and secondary migration and alteration of uranium minerals and their close associations. 3. Uranium-rich zones with high radioactive anomalies are found in Chungju, Deogpyong-Yongyuri, MiwonBoun, Daejeon-Geumsan areas in the range of 500~3,700 cps (corresponds to 0.017~0.087%U). These zones continue along strike of the beds for several tens to a few hundred meters but also discontinue with swelling and pinches at places that should be analogously developed toward underground in their vertical extentions. The drilling surveyings in those area, more than 120 holes, indicate that the depth-frequency to uranium rich bed ranging 40~160 meter is greater. 4. The features that higher radioactive anomalies occur particularly from the carbonaceous beds among the argillaceous lithologic units, are well demonstrated on the cross sections of the lithology and radioactive values of the major uranium deposits in the Ogcheon zone. However, one anomalous radioactive zone is found in a l:ornfels bed in Samgoe, near Daejeon city. This is interpreted as a thermal metamorphic effect by which original uranium contents in the underlying black slate were migrated into the hornfels bed. 5. Principal minerals of the uranium-bearing black slates are quartz, sericite, biotite and chlorite, and as to chemical composition of the black slates, $Al_2O_3$ contents appear to be much lower than the average values by its clarke suggesting that the Changri basin has rather proximal to its source area. 6. The uranium-bearing carbonaceous beds contain minor amounts of phosphorite minerals, pyrite, pyrrhotite and other sulfides but not contain iron oxides. Vanadium. Molybdenum, Barium, Nickel, Zirconium, Lead, Cromium and fixed Carbon, and some other heavy metals appear to be positive by correlative with uranium in their concentrations, suggesting a possibility of their genetic relationships. The estimated pH and Eh of the slate suggests an euxenic marine to organic-rich saline water environment during uranium was deposited in the middle part of Ogcheon zone. 7. The Carboniferous shale of Jangseong Series(Sadong Series) of Permian in Hambaegsan area having low radioactivity and in fluvial to beach deposits is entirely different in geochemical property and depositional environment from the middle part of Ogcheon zone, so-called "Pibanryong-Type Ogcheon Zone". 8. Synthesizing various data obtained by several aspects of research on uranium mineralization in the studied sequence, it is concluded that the processes of uranium deposition were incorporated with rich organic precipitation by which soluble uranyl ions, $U{_2}^{+{+}}$ were organochemically complexed and carried down to the pre-Ogcheon sea bottoms formed in transitional environment, from Red Sea type basin to Black Sea type basin. Decomposition of the organic matter under reducing conditions to hydrogen sulfide, which reduced the $UO{_2}^{+2}$ ions to the insoluble uranium dioxide($UO_2$), on the other side the heavy metals are precipitated as sulfides. 9. The EPMA study on the identification of uraninite and others and the genetic interpretation of uranium bearing slates by isotopic values of this work are given separately by Yun, S. in 1984.

• Journal of the Korean Geographical Society
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• v.30 no.3
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• pp.296-310
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• 1995

Classification of spatial units into meaningful sets is an important procedure in spatial analysis. It is crucial in characterizing and identifying spatial structures. But traditional classification methods such as cluster analysis require an exact database and impose a clear-cut boundary between classes. Scrutiny of realistic classification problems, however, reveals that available infermation may be vague and that the boundary may be ambiguous. The weakness of conventional methods is that they fail to capture the fuzzy data and the transition between classes. Fuzzy subsets theory is useful for solving these problems. This paper aims to come to the understanding of theoretical foundations of fuzzy spatial analysis, and to find the characteristics of fuzzy classification methods. It attempts to do so through the literature review and the case study of urban classification of the Cities and Eups of Kyung-Nam Province. The main findings are summarized as follows: 1. Following Dubois and Prade, fuzzy information has an imprecise and/or uncertain evaluation. In geography, fuzzy informations about spatial organization, geographical space perception and human behavior are frequent. But the researcher limits his work to numerical data processing and he does not consider spatial fringe. Fuzzy spatial analysis makes it possible to include the interface of groups in classification. 2. Fuzzy numerical taxonomic method is settled by Deloche, Tranquis, Ponsard and Leung. Depending on the data and the method employed, groups derived may be mutually exclusive or they may overlap to a certain degree. Classification pattern can be derived for each degree of similarity/distance $\alpha$. By takina the values of $\alpha$ in ascending or descending order, the hierarchical classification is obtained. 3. Kyung-Nam Cities and Eups were classified by fuzzy discrete classification, fuzzy conjoint classification and cluster analysis according to the ratio of number of persons employed in industries. As a result, they were divided into several groups which had homogeneous characteristies. Fuzzy discrete classification and cluste-analysis give clear-cut boundary, but fuzzy conjoint classification delimit the edges and cores of urban classification. 4. The results of different methods are varied. But each method contributes to the revealing the transparence of spatial structure. Through the result of three kinds of classification, Chung-mu city which has special characteristics and the group of Industrial cities composed by Changwon, Ulsan, Masan, Chinhai, Kimhai, Yangsan, Ungsang, Changsungpo and Shinhyun are evident in common. Even though the appraisal of the fuzzy classification methods, this framework appears to be more realistic and flexible in preserving information pertinent to urban classification.

• The Journal of Korean Academic Society of Nursing Education
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• v.2
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• pp.75-94
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• 1996

This survey study was aimed at identifying the degree of educational need of the KNOU(Korea National Open University) nursing students defined as admission purposes, satisfaction of distance learning education, learning methods, and courses after graduation. Among randomly assigned 1000 students, 320 KNOU nursing students who allowed to participate in the study completed the questionnaires. The data were analyzed using descriptive statistics, chi-square test, and t-test, Results of this study were as follows : 1. The admission purposes of the KNOU nursing students were 'in order to get a bachelor's degree(83.8%)', 'to acquire knowledge for task(61.3%)', or 'to be admitted for the graduate school (53.1%)' etc. Comparing the admission purposes by age, tow items- 'to explore new possibilities for myself' and 'excellent curriculum' showed statistically significant differences. These two items were also found to show significant differences by marital status. 2. For the media maintenance, the results showed that students use their own cassett radios(96.3%), VTR(49.4%), TV only for the study (44.1%), personal computer (3.31%), or joining Hitel (6.3%). 3. Listening rates of the radio lecture were 'over 80%(9.1%)', '50-80%(9.1%)', '20-50%(18.1%)', 'below 20%(30%)' and 'never(33.1%)', And record lecture showed listening rates as follows : 'over80%(17.2%)', '50-80%(15.9%)', '20-50%(24.4%)', 'below 20%(27,2%)' and 'never(14.4%)'. 4. The difficulties with KNOU life were 'listening radio lectures(38.8%)', studying by following teaching schedules (37.8%)', 'isolated self-study(10.3%)', and 'appearance in the attending classes(8.1%)'. 5. As for satisfaction with teaching methods, the data showed that 81.2% of the respondents were satisfied (or very satisfied) with 'attending classes' and 75%, with 'paper lectures'. On the other hand some of respondents were very dissatisfied with 'recorded lecture(12.8%)' and 'radio lecture(10.9%)' 6. The results also showed that the students want to have 'video conferencing lecture(77.2%)', 'cable TV(64.1%)' and 'CD ROM program' to improve learning effects. 7. Concerning learning attitudes, 48.8% of the students reported 'study mainly for examnination', and only 4.1% answered 'study every day with plan'. The learning attitude showed significant differences by marital status and age. The students also evaluated themelves as 'study very hard(5.9%)', 'study hard in general(41.6%)', 'study a little(40.3%)' and 'study little(11.9%)'. 8. The students responded the most effective learning material was the 'textbook (92.2%)'. 9. For the purposes of using the local center, the results showed 'for the attending classes(76.3%)', 'for the use of references(14.7%)', and 'for the study group(66.7%)'. 10. The results revealed that 20.3% of the respondents had ever experienced unregistration or temporary withdrawal, and 53.4% among them did not register more than one time. The most common reason for the unregistration was 'due to family affairs or their job (70.8%)'. 11. 88.1% of the respondents answered 'they will graduate without fail'. 12. Regarding the benefits from the KNOU graduation, respondents indicated 'graduate school admission(38.1%)', 'self-confidence in social life(17.5%)', and understanding social problems (10.9%)'. 13. 64.4% of the students showed that they have intention to enter the graduate school. The item 'changing work place' showed statistically significant differences by marital status and age.

• Journal of Preventive Medicine and Public Health
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• v.22 no.2 s.26
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• pp.290-301
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• 1989

This is preliminary report on anthrax epidemic occurred in an island with about 100 residents. Since 1982 there had been sudden deaths among all kinds of domestic animals including cattle, dogs, ducks, chicken and goat but only a few among cats in an isolated island about three hours distance away by ferry boat from Mokpo city. From 1986 through 1988 nine human deaths and four patients occurred, which made the government intervene for investigation on June 25 1988. The epidemiological investigation consisted of interview survey and medical examination, medical record analysis, laboratory work to isolate the pathogens under the direction of hypothesis derived from the study and further confirmation of the pathogens by international institute. The summarized results are as followings: 1. According to the interview survey there were many deaths among domestic animals usually in cold and dry season such as January through March and September through November; 36 heads of cattle leaving one head, more than 40 hogs(all), hundreds of chicken leaving few alive, goats that had taken home from mountain and two or three cats out of around 40 had sudden deaths from 1982 till 1985, when the residents stopped to purchase and take them into the island anymore. Also there were eleven persons who had experienced the similar syndrome complex to those of admitted and expired patients and four of them revealed typical chest X-ray findings; from one of these four patients(Rho) B. anthracis is isolated. 2. Medical record on patients who had been admitted, showed common characteristics of the disease course. On admission they had either gastrointestinal or upper respiratory infection symptoms which invariably progressed to septicemic nature with pulmonary interstitial infiltration and mediastinal widening/bulging, and then to deadly acute respiratory distress syndrome. At the end stage chest X-ray revealed multiple bullous emphysema. One of another characteristics was oral ulceration with bleeding occurred in about 50% of the patients. Laboratory test results in common were leukocytosis with left shift and abnormal liver and kidney functions, particularly at the later stage of the illness. 3. Epidemiological characteristics was striking in that both mortality and incidence rates were high: the mortality rate was 8.7% average, male being three times higher than females but there was no distictive clustering by age group. The incidence rate for both sexes was 28.2% and there was no sex difference although a tendency of higher incidence among older ages was noticed. The highest mortality and incidence were observed in Won village where the first death of animal occurred and with the highest frequency among three villages of the island. 4. Among twelve bacilli species isolated from various specimens, two strains, one from patient and the other from soil where the recently died cow is hurried, were confirmed as B. anthracis by Pasteur Institute and CDC of USA(strain from soil). CDC reported that the strain did not produce capsule in bicarbonate media but reacted with the bacteriophage and one of five sera taken from the patients. Mode of transmission as well as incubation period of the agent has not been established yet, which needs further investigation in relation to the antigenic structure of the variant when it is confirmed.

• Journal of KIISE:Information Networking
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• v.35 no.2
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• pp.99-111
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• 2008

In recent years, the needs for WLANs(Wireless Local Area Networks) technology which can access to Internet anywhere have been dramatically increased particularly in SOHO(Small Office Home Office) and Hot Spot. However, unlike wired networks, there are some unique characteristics of wireless networks. These characteristics include the burst packet losses due to unreliable wireless channel. Note that burst packet losses, which occur when the distance between the wireless station and the AP(Access Point) increase or when obstacles move temporarily between the station and AP, are very frequent in 802.11 networks. Conversely, due to burst packet losses, the performance of 802.11 networks are not always as sufficient as the current application require, particularly when they use TCP at the transport layer. The high packet loss rate over wireless links can trigger unnecessary execution of TCP congestion control algorithm, resulting in performance degradation. In order to overcome the limitations of WLANs environment, MAC-layer LDA(Loss Differentiation Algorithm)has been proposed. MAC-layer LDA prevents TCP's timeout by increasing CRD(Consecutive Retry Duration) higher than burst packet loss duration. However, in the wireless channel with high packet loss rate, MAC-layer LDA does not work well because of two reason: (a) If the CRD is lower than burst packet loss duration due to the limited increase of retry limit, end-to-end performance is degraded. (b) energy of mobile device and bandwidth utilization in the wireless link are wasted unnecessarily by Reducing the drainage speed of the network buffer due to the increase of CRD. In this paper, we propose a new retransmission module based on Cross-layer approach, called BLD(Burst Loss Detection) module, to solve the limitation of previous link layer retransmission schemes. BLD module's algorithm is retransmission mechanism at IEEE 802.11 networks and performs retransmission based on the interaction between retransmission mechanisms of the MAC layer and TCP. From the simulation by using ns-2(Network Simulator), we could see more improved TCP throughput and energy efficiency with the proposed scheme than previous mechanisms.