• Imaging Science in Dentistry
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• v.54 no.2
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• pp.191-199
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• 2024

Purpose: The aim of this study was to evaluate image artifacts in the vicinity of dental implants in cone-beam computed tomography (CBCT) scans obtained with different spatial orientations, tube current levels, and metal artifact reduction algorithm (MAR) conditions. Materials and Methods: One dental implant and 2 tubes filled with a radiopaque solution were placed in the posterior region of a mandible using a surgical guide to ensure parallel alignment. CBCT scans were acquired with the mandible in 2 spatial orientations in relation to the X-ray projection plane (standard and modified) at 3 tube current levels: 5, 8, and 11 mA. CBCT scans were repeated without the implant and were reconstructed with and without MAR. The mean voxel and noise values of each tube were obtained and compared using multi-way analysis of variance and the Tukey test(α=0.05). Results: Mean voxel values were significantly higher and noise values were significantly lower in the modified orientation than in the standard orientation (P<0.05). MAR activation and tube current levels did not show significant differences in most cases of the modified spatial orientation and in the absence of the dental implant (P>0.05). Conclusion: Modifying the spatial orientation of the head increased brightness and reduced spatial orientation noise in adjacent regions of a dental implant, with no influence from the tube current level and MAR.

• Transactions on Electrical and Electronic Materials
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• v.11 no.1
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• pp.24-28
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• 2010

A simulation study of a current-mode direct current (DC)-DC buck converter is presented in this paper. The converter, with a fully integrated power module, is implemented by using sense method metal-oxide-semiconductor field-effect transistor (MOSFET) and bipolar complementary metal-oxide-semiconductor (BiCMOS) technology. When the MOSFET is used in a current sensor, the sensed inductor current with an internal ramp signal can be used for feedback control. In addition, the BiCMOS technology is applied in the converter for an accurate current sensing and a low power consumption. The DC-DC converter is designed using the standard $0.35\;{\mu}m$ CMOS process. An off-chip LC filter is designed with an inductance of 1 mH and a capacitance of 12.5 nF. The simulation results show that the error between the sensing signal and the inductor current can be controlled to be within 3%. The characteristics of the error amplification and output ripple are much improved, as compared to converters using conventional CMOS circuits.

• Journal of Arbitration Studies
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• v.22 no.3
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• pp.187-213
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• 2012

The purpose of this article is to examine Fair and Equitable Treatment in International Investment Agreements. Most BITs and other investment treaties provide for FET of foreign investments. Today, this concept is the most frequently invoked standard in investment disputes. It is also the standard with the highest practical relevance: a majority of successful claims pursued in international arbitration are based on a violation of the FET standard. The concept of FET is not new but has appeared in international documents for some time. Some of these documents were nonbinding others entered into force as multilateral or bilateral treaties. Considerable debate has surrounded the question of whether the FET standard merely reflects the internationalminimum standard, as contained in customary international law, or offers an autonomous standard that is additional to general international law. As a matter of textual interpretation, it seems implausible that a treaty would refer to a well-known concept like the "minimum standard of treatment in customary international law" by using the expression "fair and equitable treatment." Broad definitions or descriptions are not the only way to gauge the meaning of an elusive concept such as FET. Another method is to identify typical factual situations to which this principle has been applied. An examination of the practice of tribunals demonstrates that several principles can be identified that are embraced by the standard of fair and equitable treatment. Some of the cases discussed clearly speak to the central roles of transparency, stability, and the investor's legitimate expectations in the current understanding of the FET standard. Other contexts in which the standard has been applied concern compliance with contractual obligations, procedural propriety and due process, action in good faith, and freedom from coercion and harassment. In short, meeting the investor's central legitimate concern of legal consistency, stability, and predictability remains a major, but not the only, ingredient of an investment-friendly climate in which the host state in turn can reasonably expect to attract foreign investment.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.204-205
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• 2020

Construction Standard Unit Price is the unit price calculated based on the market price for work items in construction projects that have already been conducted. It is used as basic data for calculating the budget price of public construction projects. In the Construction Standard Unit Price Book implemented in the second half of 2020, there are 1,810 types of unit prices. Since 2017, 100-150 construction standard unit prices have been revised semiannually (on January 1 and July 1 of each year) through Construction Site Surveys. Other work items have been set based on the rate of inflation during the corresponding period. Later in 2020, this procedure was changed, with on-site survey period extended to one year to strengthen the construction standard unit price investigation. The revisions previous announced during the second half of the year were changed only to reflect the price inflation rates. With such changes in the revisions to construction standard unit prices, one important issue that was raised: The timing of announcing the revisions during the second half of the year (reflecting the price inflation rates). The market unit wage, which is the unit price standard of labor cost that takes up a large part of the construction cost, is announced in January and September. The figures announced in September is reflected on the construction standard unit price four months later in January, but the market unit wage announced in January is reflected only six months after in July, which causes a timing issue. As such, the current study analyzed problems rising from the changed timing of the announcements of the construction standard unit price during the second half of the year, in addition to analyzing their impact on public construction projects.

• Proceedings of the KIPE Conference
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• 2014.11a
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• pp.70-71
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• 2014

In this paper, an advanced charging strategy for improving the charging performance of the Li-ion polymer battery is proposed, which is based on the battery characteristic. Simulation results show that the proposed charging current pattern can improve the charging speed of battery in comparison with the standard CC-CV (constant current - constant voltage) charging strategy and the pulse-charging strategy.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.19 no.38
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• pp.17-28
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• 1996

ISO 9000 Series International Standard have been established in 1987 and world trading patterns have changed into the request of ISO 9000 series approval. About 1100 domestic companies have currently obtained ISO 9000 series approval from domestic or foreign certification bodies. This paper presents the current status of ISO approval of domestic industries, a case study of a valve manufacturing company in Pusan, procedures for obtaining ISO approval, predictable effects as a result of approval, and recommendations.

• Journal of the Korean Professional Engineers Association
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• v.15 no.2
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• pp.52-59
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• 1982

This is to intent of the reinforcement proposal for current P.E., qualification code in necessity of improving the foreign technology inducement & technology export between advanced Country and developing or undeveloping Country as Technological Cooperation for mutual benefit. A prosal contains internationally recogniyed general term & conditions of Standard Contract form for Engineering jobs, construction works includings of plant exportation as for additional new basic knowledge for roling of business promotion & finalization in urging of more current jobs internationally to be increment of technological cooperation.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.5
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• pp.770-778
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• 1994

In this paper, the photovoltaic inverter system with instantaneous sinusoidal current tracking control is proposed to improve the utilization factor of photovoltaic power system which would be connected utility interactive system. The proposed inverter is designed to track maximum power point by two-state value control method and utility interactive operation, and to decrease output harmonics component. Optimal operating region is described by state space averaging method, and present tracking condition of standard guide line. The experimental result shows the effectiveness of inverter system using the instantaneous control method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.2
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• pp.359-373
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• 2011

Demand for rich media services is rapidly increasing and, as a result, several technologies are competing to deliver rich media services to mobile, resource-constrained devices. In this paper, we explore the existing rich media technologies and analyze their key features. In addition, in order to accommodate the new requirements introduced by emerging service models, such as service convergence, these technologies must evolve from their current status. We examine how the community intends to achieve this.

• Journal of IKEEE
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• v.12 no.4
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• pp.211-216
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• 2008

This paper proposes an 8${\times}$8 bit parallel multiplier using MOS current-mode logic (MCML) circuit for low power consumption. The proposed circuit has a structure of low-power MOS current-mode logic circuit with sleep-transistor to reduce the leakage current. The sleep-transistor is used to PMOS transistor to minimize the leakage current. Comparing with the conventional MOS current-model logic circuit, the circuit achieves the reduction of the power consumption in sleep mode by 1/50. The designed multiplier is achieved to reduce the power consumption by 10.5% and the power-delay-product by 11.6% compared with the conventional MOS current-model logic circuit. This circuit is designed with Samsung 0.35 ${\mu}m$ standard CMOS process. The validity and effectiveness are verified through the HSPICE simulation.