• The Journal of Engineering Geology
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• v.19 no.2
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• pp.139-144
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• 2009

The microseismic monitoring system with wide range of frequency has been operating in real time and it is remotely monitored at indoor and on-site for one year. This system was constructed and established in order to secure the safe and effective operation of the KAERI Underground Research Tunnel(KURT). For one year monitoring work, total 14 events were recorded in the vicinity of the KURT, and the majority of events are regarded as ultramicroseismic earthquake and artificial impacts around the tunnel. The major event is the magnitude 3.4 earthquake which was centered around Gongju city, Chungnam Province. It means that there is no significant evidence of high frequency microseismic event, which is associated with fracture initiation and/or propagation in the rock mass and shotcrete. Three components sensor was applied in order to analyze and define the direction of vibration as well as an epicenter of microseismic origin, and also properly designed and installed in a small borehole. This monitoring system is able to predict the location and timing of fracturing of rock mass and rock fall around an undreground openings as well as analysis on safety of various kinds of engineering structures such as nuclear facilities and other structures.

• Tunnel and Underground Space
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• v.22 no.3
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• pp.163-172
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• 2012

As more diesel engines have been employed in underground limestone mines with large cross section, underground space environment is worsened by diesel exhausts and heat flow. This paper aims for the ultimate goal to optimize the work place environment through assuring the optimal required ventilation rate based on the analysis of the airflow, diesel exhaust gas concentrations and the effects of mechanization and deepening working face on temperature and humidity. Due to the insufficient capacity of the main exhaust fan and poor airway management, stagnant airflows were observed at various locations, while the flow direction was reversed instantly with passing diesel equipment and the flow reversal was also made by the seasonal variation of the outside surface weather. During the loading operation, CO concentration measurements were found to be frequently higher than the threshold limit of 50 ppm, and most of the $NO_2$ measurements during drilling and loading operations shows even more serious levels surpassing the permissible limit of 3 ppm. The actual ventilation quantity was considerably less than the required quantity estimated by the mine health and safety law, and this shortage problem was less serious in colder winter showing more effectiveness of the natural ventilation.

• The KIPS Transactions:PartC
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• v.14C no.4
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• pp.331-340
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• 2007

Mobile network environments are the environments where mobile devices are distributed invisible in our daily lives so that we can conventionally use mobile services at my time and place. The fact that we can work with mobile devices regardless of time and place, however, means that we are also in security threat of leaking or forging the information. In particular, without solving privacy concern, the mobile network environments which serve convenience to use, harmonized without daily lives, on the contrary, will cause a serious malfunction of establishing mobile network surveillance infrastructure. On the other hand, as the mobile devices with various sizes and figures, public key cryptography techniques requiring heavy computation are difficult to be applied to the computational constrained mobile devices. In this paper, we propose efficient PKI-based user authentication and java-based cryptography module for the privacy-preserving in mobile network environments. Proposed system is support a authentication and digital signature to minimize encrypting and decrypting operation by compounding session key and public key based on Korean standard cryptography algorithm(SEED, KCDSA, HAS160) and certificate in mobile network environment. Also, it has been found that session key distribution and user authentication is safety done on PDA.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.1
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• pp.9-15
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• 2006

For the accurate safety assessment of potential radioactive waste disposal site which is located in the crystalline rock it is important to simulate the mass transportation through engineered and natural barrier system precisely, characterized by porous and fractured media respectively. In this work the methods to construct discrete fracture network for the analysis of flow and mass transport through fractured-porous medium are described. The probability density function is adopted in generating fracture properties for the realistic representation of real fractured rock. In order to investigate the intersection between a porous and a fractured medium described by a 2 dimensional rectangular and a cuboid grid respectively, an additional imaginary fracture is adopted at the face of a porous medium intersected by a fracture. In order to construct large scale flow paths an effective method to find interconnected fractures and algorithms of swift detecting connectivities between fractures or porous medium and fractures are proposed. These methods are expected to contribute to the development of numerical program for the simulation of radioactive nuclide transport through fractured-porous medium from radioactive waste disposal site.

• Journal of Korean Physical Therapy Science
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• v.6 no.1
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• pp.897-903
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• 1999

Many out patients of the rehabilitation center complaint a pain caused by suffering of MPS, and it brings many different kind of social and ecinomical problems such as medical expenses and the reduction in work efficiency. Therefore, we conducted a research to present a fast and effective treatment to the MPS patients. this research was conducted from November, 1996 to January 1998 with eighteen outpatients who agreed to be the subjects to our reserach. We applied the electric acupuncture on 28 different trigger point on the patients with mostly muscular-skeletal pain and some tender and radiating pain. After the treatment, VRS, VAS, PRI were used to measure the degree of the pain on the patients third and seventh visits, and following results were found. 1. To apply EAP treatment, we acupunctured 6em-Iong needles on Tps region, then the electrodes of pulse generater pg-306 E.S.T were connected on the top of the needles. the electric acupuncture therapy was conducted for 20 minutes with the intensity of 4hz - 60hz(auto wave). The treated electric intensity was the level at which the patients did not feel discomfort. 2. Thirteen out of the 18 participated patients were in their 30s and 40s(72.2%), showing highest frequency. There were more female than male with the ratio of 1 to 1:2. 3. six out of the participated patients (33.3%) had the pain for less then a week, and the average duration of the pain of the participated patients wear 0.8 years. 4. The pain occured mostly in the upper trapezius by 6 part (21.4%), then in the gluteus medius region by 4 part (14.3%). Many of the patients with the pain in the upper back area accompanied varios kind of the referred pains such as radiculopathy, HIVD and Frozen shoulder. 5. MPS occured more frequently on the right side than left side then left side and it seemed to be due to the frequent use of the right hand. 6. There was almost no difference in the measurement of the intensity of the pain right before and after the EAP treatment. Howerver, there was significant decrease in the numerical values of the VAS, and a little bit of decrease in the numerical values of the PRI after the EAP treatment. 7. Based on the results of this present research, it can be concluded that EAP can be used for the treating the myofascial pain syndrome with promptness and safety in most cases.

• The Journal of Society for e-Business Studies
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• v.18 no.4
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• pp.45-65
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• 2013

A design file can get larger in size as the complexity of the target object increases. A large design file may reside in a large parallel computing system, such as cloud computing systems, and many designers may work concurrently on the same design file. In such a case, it is obvious that we need some kind of protection mechanism so that each user can access only the area of the file he or she is entitled to. Two approaches can be taken for this problem: one is the traditional access control mechanisms and the other encryption techniques. We take the latter approach to ensure the safety of the file even in public domain such as clouding systems, and in this paper, we suggest an encryption scheme for a file where the file is encrypted in multi-layer so that each user is allowed to access the file only at the layer for which the user has the proper access right. Each layer of the file is encrypted with different keys and these keys are exposed only to those who have the right access permit. The paper explains the necessary file format to achieve this goal and discusses the file manipulation functions to handle this new file format.

• Research in Community and Public Health Nursing
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• v.1 no.1
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• pp.299-317
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• 1989

This study was attempted to find out the distribution of industrial nurses, analyze job performance by function and utilization state of medical dispensary among workers. The subjects for this study were 32 nurses working at industry located in Kyungpook and Taegu area. The data was collected through questionaire during the period of August 5-31, 1986, and analysed by the method of frequency and percentage. The following is the main findings of the study; 1. 72.2% of respondents was engaged in manufacturing industry, 33.3% in workplace whose regular workers was more than 2,000 workers. 67.7% in occupational health physicians was part-time system. 2. 93.1% of respondents was 20-29 years age group, 93.1% was graduates of junior nursing college, 96.6% was unmarried. 448% had 1-4 years of total working experiences. 3. For the motives which made them becomes industrial health nurse, 'good employment condition' was 62.1%. For the job satisfaction, 'moderate' was 586%. For the interest about the industrial health, 'moderate' was most frequent (58.6%). In the inservice education, 86.2% of the subjects was received education. 4. For the attitude of the dispensary and industrial nursing of employer, 'necessary' was most frequent (72.4%, 62.6%). 5. All establishment had dispensary facilities, 65.5% of them had independent dispensary. 6. In duty shift, 93.1% of respondents was working in one shift system. 41.4% of respondents was received from 250,000 won to 290,000 Won and 41.4% was belong to personnel section and 24.1% was direct controlled by general business section chief. 7. In the main health problem of their factories, 48.3% of respondents was work-environmental state, 24.1% was health education. 8. In the Dispensary budget, 60% of respondents was under 3,000 won per worker. 9. In the job performance rate by function, nursing service 73.1%, industrial health and nursing management 63.7%, environmental hygiene and safety management 54.5%, medical insurance 44.9%, welfare 38.4%. 10. Main health complaints among workers utilizing medical dispensary was 35.9% of respiratory system, 21.5% of gastro-intestinal system, 11.0% of skeletomuscular system.

• Culinary science and hospitality research
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• v.22 no.8
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• pp.149-156
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• 2016

The purpose of this study is to reduce the contaminants (total volatile organic compounds (TVOCs), fine particle, odor and total airborne bacteria) during cooking process in cooking chamber, and to decrease the health damage in indoor space that has bad work environment. In order to solve the shortcomings of existing air purifiers and remove all kinds of pollutants effectively, this study focused on the development of indoor air purifiers which are made of bar type. Bio-ceramics filter which combines activated carbon and loess. The air cleaners developed with 4 measuring items including TVOCs, particulate matter, complex odor and total airborne bacteria were measured comparing their pre-service test to their post-service test after a period of time. The measured results showed higher removal efficiency of 91.02% as the concentration of TVOCs was reduced from $2,500{\mu}g/m^3$ to $223{\mu}g/m^3$. Second, the particulate matter removal ratio was 97.51% efficient with average concentration of $26.68{\mu}g/m^3$. Third, the odor showed 95.20% reduction as air dilution ratio averaged out at 144. Last, total airborne bacteria was eliminated by over 94% showing the changeable concentration from $787{\sim}814CFU/m^3$ to $47{\sim}40CFU/m^3$. In addition, the removal rate of harmful pollutants is excellent, and it is expected that the environment of the existing poor cooking room will be greatly improved by using the developed air purifier in combination with the ventilation device and the stove hood.

• Asia pacific journal of information systems
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• v.19 no.3
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• pp.151-179
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• 2009

The purpose of this study is to make an empirical analysis on the factors affecting the intention for the continuous use of the BSC system, which has been recently spread in the public sector. Because the object of acceptance is the performance management system based on BSC (Balanced Scorecard) implemented in the form of information systems, this study proposes a research model by applying TAM (Technology Acceptance Model). Independent variables are factors affecting the acceptance of BSC system such as training, communication, IS support, CEO support and personal innovativeness, and we examine their effects on the dependent variable, namely, intention on continuous use via mediating variables: perceived usefulness and perceived ease of use. A questionnaire survey was conducted with public institutions(firms) that had introduced and were operating the BSC system; 264 valid questionnaires are adopted. Collected data are analyzed using SPSS 16.0 and AMOS 7.0. Results of reliability test show that all analyzed data are reliable. In validity test, one item regarding communication was excluded; 9 latent variables and 34 observed variables are used in the final analysis. Based on the results of the hypothesis test through path analysis using a structural equation model, 10 out of 16 hypotheses are accepted. Factors affecting perceived usefulness are training and IS(Information System) support. The analysis results indicate that perceived ease of use is mainly affected by IS support, CEO support, and personal innovativeness among the factors related to the acceptance of the BSC system. This suggests that, contrary to the expectation that the BSC system may be used without difficulty, the management's active support is required in order to attain expected improvement in productivity and work efficiency. This was also pointed out in case studies on the construction of the BSC system in public sectors. On the other hand, perceived ease of use is found to affect perceived usefulness. This supports the results of previous researches on TAM. Perceived ease of use and perceived usefulness are found to affect the attitude towards the use of the system. The intention on continuous use is affected more by perceived usefulness than by the attitude towards the use of system. This result supports the results of previous researches on TAM, showing that the BSC system is utilized substantially in worksites. This study is considered meaningful in that it was actually performed on users at public institutions(firms) that had introduced the BSC system and that it empirically tested hypotheses on the acceptance of the BSC system by applying TAM to the research model.

• Journal of agricultural medicine and community health
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• v.40 no.4
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• pp.240-249
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• 2015

Objectives: Farmers are known to be exposed to a variety of allergens related to the work environment. This study was conducted to determine the sensitization rates as well as South Korea that they are sensitized to certain allergens farmers through the skin prick test. Methods: By targeting a total of 1143 people living in the rural town of Gyeonggi Province, it was conducted a questionnaire containing demographic and occupational risk factors and underwent skin prick tests with 15 types of allergens(including positive and negative controls). Multivariable logistic regression analysis was used to analyze the association between occupational risk factors and skin prick test positivity. Results: Except for the 30 people whose result is invalid, positive rate of the skin prick test was 18.6% in 1,113 people. The species of house dust mite, Dermatophagoides pteronyssinus and Dermatophagoides farinae was the highest at 8.7% and 8.6%. After adjusted by age, gender, smoking and education level, odds ratio of flower plant farmers is 4.467(95% CI: 2.094-9.527) and fruit farmer is 2.275(95% CI: 1.096-4.721). In addition, the rate of sensitization to grass pollen mixture of the flower plant farmers is significantly higher(15.9%, p<0.001) than other allergens. Conclusions: Even farmers, the rate of sensitization to allergens related to the general environment, such as house dust mite is relatively dominant. However, given the presence of potential cross-reactivity between the allergens or distribution showed that the unique aspects of allergen sensitization in the flower growers, occupational cause is not be completely ruled out.