• Fire Science and Engineering
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• v.18 no.2
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• pp.57-67
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• 2004

The results of the risk assessing on general buses, consisting mainly of diesel-fueled buses, show that the frequency of the instantaneous release is 1.4${\times}$10$^{-3}$ /bus/year, from which the probability of the formation of fireball as a sub event becomes 1.7${\times}$104, and show that the leakage from the CNG-fueled buses is 0.002 event/year. Also, the frequency of gradual release due to a crack is estimated at 3.7${\times}$10$^{-3}$ /buses/year, and a subsequent probability at which this could lead to a jet flame as a sub event is 1.2${\times}$10$^{-3}$ This corresponds to 0.04event/year for the CNG-fueled buses. Dividing all the fired casualties by the running distance of diesel-fueled buses, the risk is 0.091 fire fatalities per 100-million miles. And the total fire risk fur CNG buses is approximately 0.17 per 100-million miles of travel. This means that CNG buses is twice or more dangerous than diesel buses. After all CNG buses are more susceptible to the major fires. In the aspect of the reliability of this study, generic models and the failure data used in assessing the risks of CNG buses are appropriate. However, more accurate physics-based models and databases should be supplemented with this study to provide the better results.

• Journal of the Korean Society for Library and Information Science
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• v.49 no.3
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• pp.109-133
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• 2015

The purpose of this study is to develop a model of the TOC (Table of Contents)-based research record system and to comparatively analyze its usability, in order to comprehensively and systematically manage and practically use the various research records generated from the entire process of research and development. For this purpose, the templates for technical recording and the components of each item were proposed to enable technical recording based on TOC, and structured contents were designed to organically connect between these TOC technical records and existing research records. Also, a database logical schema was developed to design a database, and a test collection was constructed on the basis of research records and TOC technical records. Finally, the model of research record system was constructed by designing TOC record search system and user interface including integrated search system. Based on this model, the usability assessment was performed by comparing the existing distributed general systems with the TOC-based research record system. As a result of the comparative analysis of these two systems, the TOC-based research record system showed generally higher utilization of research records than the general systems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.54-61
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• 2019

This paper reports a comparative review of the service quality attributes of Electronic Customs Clearance (UNI-PASS) by applying the Kano model, Timko's BW coefficients, and IGA model, as reported by Tontini et al. in terms of a service quality evaluation of electronic customs clearance as the comprehensive national customs administration information system. In addition, this study examined which quality attributes should be focused on to improve the service quality and enhance customer satisfaction using the electronic customs clearance service. The Kano, Timko, and IGA models were classified into the four common quality attributes: attractive quality, one-dimensional quality, must-be quality, and indifferent quality. Because the integrated approach was used, one-dimensional quality was included in the area for critical improvement, while the must-be quality was included in the area for intensive maintenance. In addition, the indifferent quality was included in the area of carefree, while the attractive quality was included in the area of competitive advantage.

• Journal of Korea Water Resources Association
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• v.54 no.9
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• pp.667-680
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• 2021

We investigated changes in frost days and frost-free periods and to comparatively assess frost event prediction models developed using logistic regression (LR), random forest (RF), and long short-term memory (LSTM) networks. The meteorological variables for the model development were collected from the Suwon, Cheongju, and Gwangju stations for the period of 1973-2019 for spring (March - May) and fall (September - November). The developed models were then evaluated by Precision, Recall, and f-1 score and graphical evaluation methods such as AUC and reliability diagram. The results showed that significant decreases (significance level of 0.01) in the frequencies of frost days were at the three stations in both spring and fall. Overall, the evaluation metrics showed that the performance of RF was highest, while that of LSTM was lowest. Despite higher AUC values (above 0.9) were found at the three stations, reliability diagrams showed inconsistent reliability. A further study is suggested on the improvement of the predictability of both frost events and the first and last frost days by the frost event prediction models and reliability of the models. It would be beneficial to replicate this study at more stations in other regions.

• International Area Studies Review
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• v.13 no.3
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• pp.191-210
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• 2009

Energy Security has been factor of great importance to national security, economy, society and all other areas. However, it has been in the lack of situation where there is no leading method to measure energy security nor to compare among countries until now. In the research, objective index to assess energy security has been developed and compared among the level of countries in terms of energy importing countries' perspective. Based on the suggested index, comparison for the energy security level has been explained. The implication of the research is that in terms of energy importing perspectives, method to appraise energy security and according to this, energy security rate by each countries with respect to LNG. This method is doubtlessly applicable to comparison of security rate from other resources and fluctuation of energy security by reflecting other factors. Also, discussion about how increased autonomy of resources can impact Korean energy security with regard to recent international energy development. As a consequence, it has revealed that enhanced authority of resources evokes ascendancy of energy security in a positive way.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.2
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• pp.1-14
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• 2019

In rural areas, composting is a source of non-point pollutants. However, as the quantitative distribution and loading have not been estimated, it is difficult to determine the effect of composting on stream water quality. In this study, composting datum acquired by unmanned aerial vehicle(UAV) was verified by using terrestrial LiDAR, and the management status and load change of the composting was investigated by UAV with manual control flight, thereby obtaining the basic data to determine the effect on the water system. As a result of the comparative accuracy assessment based on terrestrial LiDAR, the difference in the digital surface model(DSM) was within 0.21m and the accuracy of the volume was 93.24%. We expect that the accuracy is sufficient to calculate and utilize the composting load acquired by UAV. Thus, the management status of composting can be investigated by UAV. As the total load change of composting were determined to be $1,172.16m^3$, $1,461.66m^3$, and $1,350.53m^3$, respectively, the load change of composting could be confirmed. We expect that the results of this study can contribute to efficient management of non-point source pollution by UAV.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.9-16
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• 2019

Recently, precast PSC girder bridges have been widely applied for short and middle span bridges. The construction of the spliced girder bridges has been increasing to overcome the length limit of girder and transportation restrictions. In case of the spliced girder, the integrity of the segmental joints is very important to secure the structural soundness of bridge because the discontinuity on the segmental joints between adjacent segments could be vulnerable point. The study of segmental joint behavior with different influence factors of joint type, shear key installation, confining force is very important. In this research, finite element analysis and scaled model test with different shear key shapes and confining forces were carried out and the comparative study was performed to evaluate the segmental joint behavior of precast spliced PSC girder bridge. It was confirmed that the installation of shear key with height and depth ratio of 1/2~1/3 and applying of confining force of 1/2 of the concrete strength at the joint was effective in improving the integrity of segmental joint. In addition, the field loading test for existed precast spliced PSC girder bridge was performed and the measurement of the difference of deflection between adjacent segments at segmental joint was proposed as the assessment solution of the integrity of segmental joint.

• Journal of Wetlands Research
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• v.21 no.2
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• pp.181-190
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• 2019

Recently, Low impact development techniques, a form of nature-based solutions (NBS), were seen cost-efficient alternatives that can be utilized as alternatives for conventional stormwater management practices. This study evaluated the effectiveness of an infiltration trench (IT) and a small constructed wetland (SCW) in treating urban stormwater runoff. Long-term monitoring data were observed to assess the seasonal performance and cite the advantages and disadvantages of utilizing the facilities. Analyses revealed that the IT has reduced performance during the summer season due to higher runoff volumes that exceeded the facility's storage volume capacity and caused the facility to overflow. On the other hand, the pollutant removal efficiency of the SCW was impacted by the winter season as a result of dormant biological activities. Sediment data also indicated that fine and medium sand particles mostly constituted the trapped sediments in the pretreatment and media zones. Sediments in SCW exhibited a lower COD and TN load due to the phytoremediation and microbiological degradation capabilities of the system. This study presented brief comparison LID facilities equipped with pre-treatment zones. The identified factors that can potentially affect the performance of the systems were also beneficial in establishing metrics on the utilization of similar types of nature-based stormwater management practices.

• Korean Journal of Community Nutrition
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• v.26 no.4
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• pp.280-295
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• 2021

Objectives: This study aimed to examine the characteristics of patients according to their nutritional status as assessed by five nutritional screening tools: Patient-Generated Subjective Global Assessment (PG-SGA), NUTRISCORE, Nutritional Risk Index (NRI), Prognostic Nutritional Index (PNI), and Controlling Nutritional Status (CONUT) and to compare the agreement, sensitivity, and specificity of these tools. Methods: A total of 952 gastric cancer patients who underwent gastrectomy and chemotherapy from January 2009 to December 2012 at the Samsung Medical Center were included. We categorized patients into malnourished and normal according to the five nutritional screening tools 1 month after surgery and compared their characteristics. We also calculated the Spearman partial correlation, Cohen's Kappa coefficient, the area under the curve (AUC), sensitivity, and specificity of each pair of screening tools. Results: We observed 86.24% malnutrition based on the PG-SGA and 85.82% based on the NUTRISCORE among gastric cancer patients in our study. When we applied NRI or CONUT, however, the malnutrition levels were less than 30%. Patients with malnutrition as assessed by the PG-SGA, NUTRISCORE, or NRI had lower intakes of energy and protein compared to normal patients. When NRI, PNI, or CONUT were used to identify malnutrition, lower levels of albumin, hemoglobin, total lymphocyte count, total cholesterol, and longer postoperative hospital stays were observed among patients with malnutrition compared to those without malnutrition. We found relatively high agreement between PG-SGA and NUTRISCORE; sensitivity was 90.86% and AUC was 0.78. When we compared NRI and PNI, sensitivity was 99.64% and AUC was 0.97. AUC ranged from 0.50 to 0.67 for comparisons between CONUT and each of the other nutritional screening tools. Conclusions: Our study suggests that PG-SGA and NRI have a relatively high agreement with the NUTRISCORE and PNI, respectively. Further cohort studies are needed to examine whether the nutritional status assessed by PG-SGA, NUTRISCORE, NRI, PNI, and CONUT predicts the gastric cancer prognosis.

• International Journal of Computer Science & Network Security
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• v.21 no.5
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• pp.73-83
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• 2021

The information space, the main components of which are information resources, means of information interaction, and information infrastructure, is a sphere of modern social life in which information communications play a leading role. The objective process is the gradual but stable entry of the national information space into the European and world information sphere, in the context of which there is a legitimate question of its protection as one of the components of the national security of Ukraine. However, the implementation of this issue in practice immediately faces the need to respect the rights and fundamental freedoms guaranteed by international regulations and the Constitution of Ukraine, especially in the field of cybersecurity. The peculiarity of the modern economy is related to its informational nature, which affects the sharp increase in cyber incidents in the field of information security, which is widespread and threatening and affects a wide range of private, corporate, and public interests. The problem of forming an effective information security system is exacerbated by the spread of cybercrime as a leading threat to information security both in Ukraine and around the world. The purpose of this study is to analyze the state of cybersecurity and on this basis to identify new areas of the fight against cybercrime in Ukraine. Methods: the study is based on an extensive regulatory framework, which primarily consists of regulatory acts of Ukraine. The main methods were inductions and deductions, generalizations, statistical, comparative, and system-structural analysis, grouping, descriptive statistics, interstate comparisons, and graphical methods. Results. It is noted that a very important component of Ukraine's national security is the concept of "information terrorism", which includes cyberterrorism and media terrorism that will require its introduction into the law. An assessment of the state of cybersecurity in Ukraine is given. Based on the trend analysis, further growth of cybercrimes was predicted, and ABC analysis showed the existence of problems in the field of security of payment systems. Insufficient accounting of cybercrime and the absence in the current legislation of all relevant components of cybersecurity does not allow the definition of a holistic system of counteraction. Therefore, the proposed new legal norms in the field of information security take into account modern research in the field of promising areas of information technology development and the latest algorithms for creating media content.