• International Journal of High-Rise Buildings
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• v.11 no.4
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• pp.363-368
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• 2022

For taller buildings with unconventional architecture, refined structural systems or in geographical areas with high wind conditions, performance-based design can be seen as an enhanced design process and is either a supplement to, or alternative to a prescriptive code-based design. The ultimate goal of Performance-Based Wind Design (PBWD) is to result in a building that better addresses key goals of performance over the buildings full life cycle. Major innovations around the use of a PBWD approach include nonlinear dynamic analysis for wind design, limited inelasticity in the main wind force resisting system elements, and system-based performance criteria. This paper discusses potential considerations and benefits made when using a performance-based approach, in addition to the general practicality of use, for the structural design on a few key tall buildings.

• Journal of Information Technology Applications and Management
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• v.30 no.6
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• pp.17-29
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• 2023

In this paper, we aim to propose cyber security considerations and countermeasures for infrastructure and services in the UAM(Urban Air Mobility) Air Traffic Management field, which is one of the key elements of the UAM market that has not yet bloomed. Air traffic management is an important factor for safe navigation and social acceptance of UAM. In order to realize air traffic management, infrastructure and services based on solid network connectivity must be established. And for industries where connectivity is the core component, it can become an infiltration route for cyber threats. Therefore, cyber security is essential for the infrastructure and services. In detail, we will look into the definition of the existing air traffic management field and the cyber threats. In addition, we intend to identify cyber security threat scenarios that may occur in the newly designed UAM air traffic management infrastructure. Moreover, in order to study the cyber security countermeasures of the UAM air traffic management infrastructure, there will be analysis of the UAM operation concept. As a result, countermeasures applicable to the infrastructure and service fields will be suggested by referring to the cyber security frameworks.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1156-1165
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• 2017

A high performance interleaved bridgeless boost power factor correction (PFC) rectifier operating under the critical current conduction mode (CrM) is proposed in this paper to improve the efficiency and system performance of various applications, such as nano-grid systems. By combining the interleaved technique with the bridgeless topology, the circuit contains two independent branches without rectifier diodes. The branches operate in interleaved mode for each respective half-line period. Moreover, when operating in CrM, all the power switches take on soft-switching, thereby reducing switching losses and raising system efficiency. In addition, the input current flows through a minimum amount of power devices. By employing a commercial PFC controller, an effective control scheme is used for the proposed circuit. The operating principle of the proposed circuit is presented, and the design considerations are also demonstrated. Simulations and experiments have been carried out to evaluate theoretical analysis and feasibility of the proposed circuit.

• Journal of the Korea Convergence Society
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• v.13 no.5
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• pp.551-558
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• 2022

The purpose of this study is to identify considerations for oral health and oral health education through group interviews with the general public and those diagnosed with diabetes among the elderly over 65 years of age. The subjects of this study were divided into two groups: 5 healthy people and 5 diabetic patients over 65 who visited the Senior Welfare Center in G city, and each group had a 60-70 minute interview. As a result of the study, four key themes were derived: 'Knowledge on the relationship between diabetes and oral disease', 'Oral health status', 'Oral health management method', and 'Considerations for oral health education'. Healthy people who participated in this study answered that the contents they thought necessary for oral health education were periodontal management method, implant, holistic oral care, and systemic health, and diabetic patients answered that diabetes, periodontal management method, and importance of practicing oral care. Based on the results of this study, it is considered that it is necessary to develop a customized oral health education program for diabetic elderly patients in the future.

• Journal of The Korean Association For Science Education
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• v.29 no.2
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• pp.253-266
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• 2009

This study was focused on analyzing students' informal reasoning patterns and their considerations in decision-making on socioscientific issues. This study involved 20 undergraduate students (10 biology majors and 10 non-biology majors) and showed how the two groups responded on socioscientific issues. Semi-structured interviews were conducted twice respectively based on six scenarios of gene therapy and human cloning. The result showed 93% of the total number of participants' decisions were made by rationalistic reasoning, whereas emotional reasoning was 49%, and intuitive reasoning was 27%. Students usually used two or three informal reasoning patterns together. Most of the students took more consideration on social factors. Some perceived ethical and moral implications of the issues, but they did not consider them seriously. They made their decisions depending on their own values, etc. 65% of the participants got their information on socioscientific issues from the mass media. Biology majors hardly used intuitive reasoning compared to non-biology majors. The Biology major group took into deep considerations on socioscientific issues while the non-biology major group seemed to interpret the given scenarios simply. This implied that the content knowledge was a significant factor of their decision-making. Therefore, it is necessary to develop proper science courses for non-major students to improve their decision-making on socioscientific issues. So, when we develop educational materials or programs, we should consider students' reasoning patterns, their considerations in decision-making, and their content knowledge. And because the mass media has the potential to play a key role for an effective education, we need to make a plan to make a practical application.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.1
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• pp.11-18
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• 2013

In order to prevent tampering and reverse engineering of executive code, this paper propose a new tamper resistant software mechanism. This paper presents a cryptographic MAC function and a relationship which has its security level derived by the importance of code block instead of by merely getting the encryption and decryption key from the previous block. In this paper, we propose a cryptographic MAC function which generates a dynamic MAC function key instead of the hash function as written in many other papers. In addition, we also propose a relationships having high, medium and low security levels. If any block is determined to have a high security level then that block will be encrypted by the key generated by the related medium security level block. The low security block will be untouched due to efficiency considerations. The MAC function having this dynamic key and block relationship will make analyzing executive code more difficult.

• Journal of Gastric Cancer
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• v.20 no.3
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• pp.290-299
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• 2020

Purpose: Recently, totally laparoscopic gastrectomy has been gradually accepted by surgeons worldwide for gastric cancer treatment. Complete dissection of the lymph nodes and the establishment of the surgical margin are the most important considerations for curative gastric cancer surgery. Previous studies have demonstrated that indocyanine green (ICG)-traced laparoscopic gastrectomy significantly improves the completeness of lymph node dissection. However, it remains difficult to identify the tumor location intraoperatively for gastric cancers that are staged ≤T3. Here, we investigated the feasibility of ICG fluorescence for lymph node mapping and tumor localization during totally laparoscopic distal gastrectomy. Materials and Methods: Preoperative and perioperative data from consecutive patients with gastric cancer who underwent a totally laparoscopic distal gastrectomy were collected and analyzed. The patients were categorized into the ICG (n=61) or the non-ICG (n=75) group based on whether preoperative endoscopic mucosal ICG injection was performed. Results: The ICG group had a shorter operation time and less intraoperative blood loss. Moreover, significantly more lymph nodes were harvested in the ICG group than the non-ICG group. No pathologically positive margin was found and there was no significant difference in either the proximal or distal surgical margins between the 2 groups. Conclusions: Near-infrared fluorescence imaging with ICG can be successfully used in totally laparoscopic distal gastrectomy, and it contributes to both the completeness of D2 lymph node dissection and confirmation of the gastric transection line. Well-designed prospective randomized studies are needed in the future to fully validate our findings.

• Journal of the Korean Society for Library and Information Science
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• v.58 no.1
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• pp.373-393
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• 2024

This study aims to propose the considerations for developing the guidelines for recording a preferred title in musical works by analyzing the RDA rules and guidelines of several national libraries. First, RDA rules were analyzed, and the primary rules for consideration were examined by reviewing RDA application guidelines from eight national libraries that have developed their own guidelines for alternatives and options of RDA rules. Then, by analyzing the contents of each guideline, including MLA, LC-PCC, and DACH, practical considerations was to provide. First, the original language title should be adopted in the selection of preferred title, but if the title in the original language is not suitable for domestic users, the title in other languages should be used. Second, the preferred title was examined in aspects of works with one part, works with more than one part, the complete works of one author, the compilation of a specific type of composition, the incomplete compilation, and the compilation of several composers. Third, medium of performance, numeric numbers, key, and other identifying characteristics were presented as additional factors for consideration in the recording. Fourth, it is necessary to designate or present a control vocabularies for the types of compositions and the medium of performance. This study suggests considerations in developing guidelines for recording the preferred title for RDA musical works, and it will be possible to contribute to the development of rules related to preferred titles for musical works and guidelines for recording the preferred title for musical works in libraries.

• Structural Engineering and Mechanics
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• v.63 no.4
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• pp.509-519
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• 2017

Wind field in mountainous regions demonstrates unique distribution characteristic as compared with the wind field of the flat area, wind load and wind effect are the key considerations in structural design of television towers situated in mountainous regions. The television tower to be constructed is located at the top of Xiushan Mountain in Nanjing, China. In order to investigate the impact of terrain factors of hilltops on wind loads, firstly a wind tunnel test was performed for the mountainous area within 800m from the television tower. Then the tower basal forces such as bending moments and shear strength were obtained based on high frequency force balance (HFFB) test. Based on the experiments, the improved method for determining the load combinations was applied to extract the response distribution patterns of foundation internal force and peak acceleration of the tower top, then the equivalent static wind loads were computed under different wind angles, load conditions and equivalent goals. The impact of terrain factors, damping ratio and equivalent goals on the wind load distribution of a television tower was discussed. Finally the equivalent static wind loads of the television tower under the 5 most adverse wind angles and 5 most adverse load conditions were computed. The experimental method, computations and research findings provide important references for the anti-wind design of high-rise structure built on hilltops.

• Wind and Structures
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• v.31 no.3
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• pp.269-285
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• 2020

The statistical characteristics of typhoon wind speed records tend to have a considerable time-varying trend; thus, the stationary wind model may not be appropriate to estimate the wind characteristics of typhoon events. Several nonstationary wind speed models have been proposed by pioneers to characterize wind characteristics more accurately, but comparative studies on the applicability of the different wind models are still lacking. In this study, three landfall typhoons, Ampil, Jongdari, and Rumbia, recorded by ultrasonic anemometers atop the Shanghai World Financial Center (SWFC), are used for the comparative analysis of stationary and nonstationary wind characteristics. The time-varying mean is extracted with the discrete wavelet transform (DWT) method, and the time-varying standard deviation is calculated by the autoregressive moving average generalized autoregressive conditional heteroscedasticity (ARMA-GARCH) model. After extracting the time-varying trend, the longitudinal wind characteristics, e.g., the probability distribution, power spectral density (PSD), turbulence integral scale, turbulence intensity, gust factor, and peak factor, are comparatively analyzed based on the stationary wind speed model, time-varying mean wind speed model and time-varying standard deviation wind speed model. The comparative analysis of the different wind models emphasizes the significance of the nonstationary considerations in typhoon events. The time-varying standard deviation model can better identify the similarities among the different typhoons and appropriately describe the nonstationary wind characteristics of the typhoons.