• The Journal of Advanced Prosthodontics
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• v.12 no.5
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• pp.307-315
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• 2020

PURPOSE. The purpose of this study was to evaluate the occurrence of displacement while tightening the screw of scan bodies, which were compared according to the material type. MATERIALS AND METHODS. Three types of scan bodies whose base regions were made up of polyether ether ketone (PEEK) material [Straumann Group, Dentium Group, and Myfit (PEEK) Group] and another scan body whose base region was made up of titanium material [Myfit (Metal) Group] were used (15 per group). The reference model was fabricated by aligning the scan body library on the central axis of the implant, and moving this position by the resin model. The screws of the scan bodies were tightened to the implant fixture with torques of 5 Ncm, 10 Ncm, and a hand tightening torque. After the application of the torque, the scan bodies were scanned using a laboratory scanner. To evaluate the vertical, horizontal, and 3-dimensional (3D) displacements, a 3D inspection software program was used. To examine the difference among groups, one-way analysis of variance and Tukey's HSD post hoc test were used (α=.05). RESULTS. There were significant differences in 3D, vertical, and horizontal displacements among the different types of scan bodies (P<.001). There was a significantly lower displacement in the Straumann group than in the Myfit (PEEK) and Dentium groups (P<.05). CONCLUSION. The horizontal displacement in all groups was less than 10 ㎛. With the hand tightening torque, a high vertical displacement of over 100 ㎛ occurred in PEEK scan bodies (Myfit and Dentium). Therefore, it is recommended to apply a tightening torque of 5 Ncm instead of a hand tightening torque.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.2
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• pp.102-113
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• 2014

Present communication and network environment have been moving rapidly toward wireless and mobile base from existing wired internet base. This change of trend influences greatly on business methods accordingly. Therefore many enterprises are trying hard to adopt mobile business in order to gain competitive edge of their products and they are in need of more effective and stable mobile solutions. However, the method of establishing optimal mobile computing environment and how to handle existing business process and use vast amount of database are still needed. Therefore this paper tries to realize a mobile middleware system as a mobile business establishment supporting tool that could link various computational resource on wired internet with wireless LAN, mobile phone network, and mobile devices. To accomplish that specific goal, this paper provides a powerful tool of mobile and wireless application data access that could expand the line of business already set up in general enterprises easily and rapidly into mobile environment. When this suggested solution is applied in the field of industry, it can economically change legacy business process into mobile environment without having to change existing logic and resources at all.

• The Korean Society of Law and Medicine
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• v.8 no.1
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• pp.137-177
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• 2007

The medical expenses review system in Korea has developed under fee-for-service system with its own unique structure. The importance of reviewing medical expenses has been emphasized, as the size of medical expenditures moving through the health insurance legal context and its weight in the national economy have increased very rapidly. It is, however, analyzed that the feuds and arguments continue among the stakeholders for the lack of laws supporting the medical expenses review system. The medical expenses review is a series of administrative procedures, deciding whether claims from medical care institutions to the insurer are legal and valid or not. It mainly controls the increase of unnecessarily excessive health insurance claim and prevents fraudulent claim and abuse and checks the less use or unsuitable use of medical resources. It also works a function guarantees medical benefits for the appropriate treatment according to the object of health insurance system as a social insurance scheme. The dispute on legal base of the medical expenses review is about the source of law in the medical expenses review. There are the Health Insurance Act and administrative laws as jus scriptum and the guidelines of review as administrative orders. The medical expenses review should reflect various factors, such as the development of medical healthcare technologies, the health expenditures distribution, the financial situation of the health insurance, and the evaluation on the level of appropriate benefits. It is also likely to adapt to the traits of characters of medicine, and trends and transition, Besides it should judge the legality and the validity of medical benefits expenditures by synthesizing these all factors. And the evaluation system of appropriateness of medical benefits was administrative procedure which was consecutive with reviewing the medical expenses system and it was intended to make up for the result of reviewing the medical expenses in more comprehensive levels.

• Journal of Korean Society of Transportation
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• v.29 no.5
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• pp.33-42
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• 2011

As the scale of transfer center becomes gradually large, transfer information service considering convenience of users in motion in a large transfer center is required. This service provides moving users with information through individual portable terminals such as mobile phone or, smart phone which are capable of wireless communication. In particular, technology of measuring indoor location using Wi-Fi is in a stage of commercial practice and indoor/outdoor location-base transfer information service is possible through smart phones with built-in GPS and Wi-Fi. In this study, we suggest information services that support transfer activities based on the locations of visitors inside transfer centers. This study also suggests the logical and physical architectures, and physical components required for the flow of information as well as the target connected standardized information for connecting destinations of each proposed draft standards.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.788-791
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• 2005

Nodal displacements are referred to the Initial configuration in the total Lagrangian formulation and to the last converged configuration in the updated Lagrangian formulation. This research proposes a relative nodal displacement method to represent the position and orientation for a node in truss structures. Since the proposed method measures the relative nodal displacements relative to its adjacent nodal reference frame, they are still small for a truss structure undergoing large deformations for the small size elements. As a consequence, element formulations developed under the small deformation assumption are still valid fer structures undergoing large deformations, which significantly simplifies the equations of equilibrium. A structural system is represented by a graph to systematically develop the governing equations of equilibrium for general systems. A node and an element are represented by a node and an edge in graph representation, respectively. Closed loops are opened to form a spanning tree by cutting edges. Two computational sequences are defined in the graph representation. One is the forward path sequence that is used to recover the Cartesian nodal displacements from relative nodal displacements and traverses a graph from the base node towards the terminal nodes. The other is the backward path sequence that is used to recover the nodal forces in the relative coordinate system from the known nodal forces in the absolute coordinate system and traverses from the terminal nodes towards the base node. One closed loop structure undergoing large deformations is analyzed to demonstrate the efficiency and validity of the proposed method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.9
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• pp.1220-1226
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• 2021

In this paper, we propose a probabilistic handover scheme for enhancing spectral efficiency in drone-based wireless communication systems. When a moving drone base station (DBS) provides the drone-based wireless communication service to a user equipment (UE) located on the ground, our proposed handover scheme considers the distance between DBS and UE and small scale fading. In addition, our proposed handover scheme considers a handover probability to mitigate the signalling overhead that may occur when performing frequent handovers. Through simulations for drone-based wireless communication systems, we evaluate the spectral efficiency and the handover probability of our proposed handover scheme and the conventional handover scheme. The simulation results show that our proposed handover scheme can achieve higher average spectral efficiency than the conventional handover scheme which considers only the distance between DBS and UE.

• Journal of KIISE:Computing Practices and Letters
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• v.12 no.1
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• pp.66-77
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• 2006

In this paper, we researched the searching and tracking locations of a home resident using ON/OFF switches and sensors and designed a remote monitoring system. As an implementation environment, this system is developed on the base of the distributed object group framework we have developed from previous works. In order to trace the moving locations of a home resident, we firstly showed a home structure which attaches ON/OFF switches and sensors to home appliances and indoor facilities being fixed in home. Whenever a home resident opens/closes these objects, the signals operated from ON/OFF switches and sensors are sent to a home server system. In this time, the real locations of ON/OFF switches and sensors that the signals are being occurred must be the current location that he/she stays. A home server system provides the functionalities that map the real location of a resident in home to virtual location designed on remote desk-tops or terminals like PDAs, and that construct a healthcare database consisted of moving patterns, moving ranges, momentum for analyzing the given searching locations and times Finally, this system provides these information for remotely monitoring services.

• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.553-560
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• 2023

The study is about domestic industries following the migration of hubs (innovation, manufacturing) to other countries and the hub-oriented US industries (batteries, semiconductors, electric vehicles). Additionally, the ongoing trade tensions between the United States and China may have also played a role in companies moving their operations to the United States. The result of such a move could potentially include job creation in the United States, as well as increased investment in the U.S. manufacturing sector. However, it is also possible that there could be negative consequences, such as higher prices for consumers or disruptions to supply chains during the relocation process. However, such IRA, Chips Act scenario would likely also have negative consequences (Inflation in the home country) for the countries whose industries moved to the US, as they would lose jobs, investment, and possibly face economic difficulties as a result. As the result of the empirical analysis of the export scale of Korea and the United States, changes in the movement of global supply hubs are related to factors such as geopolitical price increases and consumption declines. In order to respond to these changes, this paper emphasizes the need to prevent the result of de-advantage by moving the production area of the scale.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.283-285
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• 2012

In this research, we produced a simple momentum measurement system which figures out information for the real-time travel distance with modularizing a momentum measurement system by using the acceleration sensor, MCU and Bluetooth to measure the exact momentum. In the simulation experiments, we compared the reliability and accuracy of the new momentum measurement system with those of existing momentum measurement systems to confirm that the new momentum measurement system shows superior reliability and accuracy. Base on this results, we will produce the enhanced momentum measurement system, compact and possible to shoe-mount, in future.

• Geomechanics and Engineering
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• v.13 no.4
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• pp.601-619
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• 2017

Cantilever retaining wall movements generally depend on the intensity and duration of ground motion, the response of the soil underlying the wall, the response of the backfill, the structural rigidity, and soil-structure interaction (SSI). This paper investigates the effect of material properties on seismic response of backfill-cantilever retaining wall-soil/foundation interaction system considering SSI. The material properties varied include the modulus of elasticity, Poisson's ratio, and mass density of the wall material. A series of nonlinear time history analyses with variation of material properties of the cantilever retaining wall are carried out by using the suggested finite element model (FEM). The backfill and foundation soil are modelled as an elastoplastic medium obeying the Drucker-Prager yield criterion, and the backfill-wall interface behavior is taken into consideration by using interface elements between the wall and soil to allow for de-bonding. The viscous boundary model is used in three dimensions to consider radiational effect of the seismic waves through the soil medium. In the seismic analyses, North-South component of the ground motion recorded during August 17, 1999 Kocaeli Earthquake in Yarimca station is used. Dynamic equations of motions are solved by using Newmark's direct step-by-step integration method. The response quantities incorporate the lateral displacements of the wall relative to the moving base and the stresses in the wall in all directions. The results show that while the modulus of elasticity has a considerable effect on seismic behavior of cantilever retaining wall, the Poisson's ratio and mass density of the wall material have negligible effects on seismic response.