• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.2
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• pp.181-188
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• 2010

This paper presents the control algorithm of active walking aids estimating external torque of the wheels from user's will. Nowadays, interest of the walking aids is increased according to the increase in population of elder and handicapped person. Although many walking aids are developed, most of walking aids don't have any actuators for its movement. However, general walking aids have weakness for its movement to upward/download direction of slope. To overcome the weakness of the general walking aids, many researches for active type walking aids are being progressed. Unfortunately it is difficult to precision control of walking will during its movement, because it is not easy to recognize user's walking will. Many kinds of methods are proposed to recognize of user's walking will. In this paper, we propose control algorithm of walking aids by using torque estimation from wheels. First, we measure wheel velocity and voltage at the walking aids. From these data, external forces are extracted. And then walking will that is included by walking velocity and direction is estimated. Finally, walking aids are controlled by these data. Here, all the processes are verified by simulation.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.4
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• pp.163-172
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• 2022

This study investigates the IPI (Information Protection Intention) of DHS (Digital Healthcare Service) providers by introducing PMT (Protection Motivation Theory). This study examines the effects of protection motivation, such as threat appraisal and coping appraisal, on IPI, such as ICI(Induction Control Intention) and SDI(Self Defense Intention). The research model, based on the PMT, adopted severity, vulnerability, reaction efficacy and self-efficacy as independent variables. The research model was validated through quantitative research, a survey of 222 DHS providers in South Korea, using structural equation modeling. The results show that (1) a clear awareness of the consequences of security threats increases the understanding of DHS providers on the severity of closure of healthcare information, and thus may decreases abuse of DHS by providers; (2) user confidence and satisfaction on the security system may make them be confident that they can handle the closure of healthcare information by themselves; and (3) although DHS providers are realizing the consequences of closure of healthcare information, they think that they are unlikely to encounter such situations. As a result of this study, venture companies that provide DHS need to provide contents that can continuously increase providers' security level in order to increase providers' information protection intention. It suggests that IPI is important through trust of healthcare service providers.

• Journal of Digital Convergence
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• v.11 no.11
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• pp.509-519
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• 2013

The purpose of this study was to identify the factors related to awareness, treatment, and control of hypertension in Korea using data from the 4th KNHANES. The analytical technique employed multivariate logistic regression analysis and the major findings of this research are as follows. First, awareness of hypertension was positively associated with age, occupation, self-rated health, Body Mass Index, and health examination since 2 years ago, in both males and females. Second, treatment of hypertension was positively associated with age, self-rated health, Body Mass Index, and health examination since 2 years ago, in both males and females. Third, control of hypertension was positively associated with age, self-rated health, Body Mass Index, and health examination since 2 years ago, in both males and females. Finally, the results of analysis suggest that the government should especially focus on the vulnerable group and continue to strengthen effective efforts for improving awareness, treatment, and control of hypertension.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.8
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• pp.107-112
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• 2016

Safety Critical Instrumentation and Control Systems perform those functions to maintain nuclear power plants' parameters within acceptable limits established for a design basis events and anticipated operating occurrence to ensure safety function. Those digitalized systems shall protect inadvertent and non-malicious behavior to ensure the reliable operation of systems, known as a Secure Development and Operational Environment(SDOE). SDOE would be established through managerial and technical controls. The objective of this paper is to evaluate the effectiveness of Cyclic Redundancy Checksum diagnostic, which is one of technical controls for SDOE, that can confirm the integrity of software of I&C systems to establish the secure environment. The results of this assessment would be the practical implementation of design and safety review of nuclear I&C systems.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.6
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• pp.1243-1252
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• 2012

Due to the widespread use of smart devices, threats of direct observation attacks such as shoulder surfing and recording attacks, by which user secrets can be stolen at user interfaces, are increasing greatly. Although formal security models are necessary to evaluate the possibility of and security against those attacks, such a model does not exist. In this paper, based on the previous work in which a HCI cognitive model was firstly utilized for analyzing security, we propose STM-GOMS model as an improvement of GOMS-based model with regard to memory limitations. We then apply STM-GOMS model for analyzing usability and security of a password entry scheme commonly used in smart devices and show the scheme is vulnerable to the shoulder-surfing attack. We finally conduct user experiments to show the results that support the validity of STM-GOMS modeling and analysis.

• Journal of the Korea Society of Computer and Information
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• v.16 no.6
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• pp.165-178
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• 2011

A gigantic ship is constructed by assembling various types of ship blocks, each block being made by cutting and piecing the steel-plates together. The steel-plate piling process as the initial stage of ship construction sorts and manages the steel-plates according to the ship blocks that the steel-plates are used to make. The steel-plate piling process poses some problems such as process delay due to piling errors, safety vulnerability due to the handling of extra heavy-weight objects, and the uncertainty of work plan due to lack of information management in the pile spaces. We constructed a steel-plate piling process system based on the context-aware computing to resolve such problems. We built simulation system that can simulate the piling process and then established a smart space within the system by using tags, sensors and a real-time location system in order to collect context information. Workers receive an appropriate or intelligent service from the system.

• Proceedings of the Korean Geotechical Society Conference
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• 1998.04a
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• pp.47-60
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• 1998

It is considered in this paper that the main causes of tunnel collapse during the construction were the insufficiency of data of geotechnical investigations, or their limits due to special ground condition such as its heterogeneity and anisotropy It is thought that safety of ground can be affected by the geological conditions such as presences of discontinuities in good intact rocks, and considered to be necessary that awareness of the conditions of discontinuities in advance is important to apply adequate reinforcement measures. It is also shown that a serious accident had occurred because of the unawareness of the permeable alluvial deposits at the top of the tunnel. And it is shown that the example of application of the results of geotechnical investigation such as face-mapping, pilot boring etc. during tunnel construction, and a serious deformation of tunnel under special geological condition. Therefore, it is strongly recommended to perform an adequate geotechnical investigation to confirm the geotechnical conditons of ground before design, and supplimentary investigation is also needed depending on conditions for safe and econonic construction.

• Journal of Korea Port Economic Association
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• v.22 no.4
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• pp.1-17
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• 2006

In the Bill of Lading of The Irbenskiy Proliv is not subject to the Hague-Visby Rules in accordance with paragraphs (A) and/or (E) of cl.1 or to the Hague Rules in accordance with paragraphs (B) and/or (D) of cl.1. The Irbenskiy Proliv is very rare case that is effective to exempt the carrier as literal words of Bill of Lading. The action concerns cargoes of perishable goods shipped from Brazil to Japan, under Bills of Lading each of which contained an extensive carrier's exemption clause. A preliminary issue was ordered to be determined on the question whether c1.4 is effective to exempt the ralliers from any potential liability for the claims in this case. The court held that there is no reason to reject c1.4 as part of each of the contracts contained in or evidenced by the bills of lading; and it protects the carrier where damage to the goods shipped results from such causes. It is therefore effective to exempt the carriers from any potential liability for those claims.

• Fire Science and Engineering
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• v.25 no.6
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• pp.127-135
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• 2011

In this study, we assumed the kitchen fire raising the highest fire rate in apt. and analyzed the fire risk to use CFD in order to estimate the problem of evacuation equipment and the fire vulnerability of 16 or fewer storey apartment. Fire occurring in the kitchen is expended to the livingroom and other rooms. We analyzed that the temperature effected by heat was more than $60^{\circ}C$ after 90 sec in the entrance of apartment unit. If fire is early recognized by men and men don't escape in time, it have too huge demage to block the exit. When the evacuation equipment suggested in this study was installed in order to solve the problem of evacuation equipment, we analyzed that it was estimated more than safe in safety evaluation by heat and heat flux.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.4
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• pp.379-384
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• 2014

The most critical rotating parts of a gas turbine engine are turbine blades and disc, given that they must operate under severe conditions such as high turbine inlet temperature, high speeds, and high compression ratios. Owing to theses operating conditions and high rotational speed energy, some failures caused by turbine disks and blades are categorized into catastrophic and critical, respectively. To maximize the margin of structural integrity, we aim to optimize the vulnerable area of disc-blade interface region. Then, to check the robustness of the obtained optimized solution, we evaluated structural reliability under uncertainties such as dimensional tolerance and fatigue life variant. The results highlighted the necessity for and limitations of optimization which is one of deterministic methods, and pointed out the requirement for introducing reliability-based design optimization which is one of stochastic methods. Thermal-structural coupled-filed analysis and contact analysis are performed for them.