• Journal of Power Electronics
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• v.16 no.3
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• pp.840-848
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• 2016

A primary-side regulation AC-DC converter operating in the PFM (Pulse Frequency Modulation) mode with a high precision output current is designed, which applies a novel inductance compensation technique to improve the precision of the output current, which reduces the bad impact of the large tolerance of the transformer primary side inductance in the same batch. In this paper, the output current is regulated by the OSC charging current, which is controlled by a CC (constant current) controller. Meanwhile, for different primary inductors, the inductance compensation module adjusts the OSC charging current finely to improve the accuracy of the output current. The operation principle and design of the CC controller and the inductance compensation module are analyzed and illustrated herein. The control chip is implemented based on a TSMC 0.35μm 5V/40V BCD process, and a 12V/1.1A prototype has been built to verify the proposed control method. The deviation of the output current is within ±3% and the variation of the output current is less than 1% when the inductances of the primary windings vary by 10%.

• 한국디지털정책학회:학술대회논문집
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• 2005.11a
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• pp.231-242
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• 2005

The purpose of this study is to generate a proper regulation improvement direction of the public IT project contract law through the current four contract methods and three methods of the awarding party of a contract method. The research method for this paper is derived from the written materials of the present public IT project contract law. Two problems have been processed in order to produce the results: the current contract methods and the awarding party of a contract method. The current contract methods consist of a competition contract, a private contract, and a supply methodology contract. The methods of the awarding party of a contract display a qualified evaluation regulation, the 2nd step competition bid, a standard cost separation tender, and a contract by a negotiation. The results exhibit that the general competition contract consists of four improvement items. The contract by a negotiation contains five improvement items. The group private contract has one improvement item. And the private contract includes one improvement item. These results implicate that the current public IT project contract law demands better improvement work for the ubiquitous Korea.

• Journal of Society of Preventive Korean Medicine
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• v.20 no.2
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• pp.87-95
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• 2016

Objectives : Traditional medicine(TM) of East Asia has been taking its status as part of complementary and alternative medicine(CAM) in the UK. However, the efficacy and safety issues make it hard to be accepted in the healthcare system. The aim of the research is to find out the current status of TM of East Asia in the UK and to discuss some issues around its acceptance as formal healthcare method. Methods : Articles, books and regulations related to the acceptance of TM of East Asia were analysed and the internet websites were visited such as Westlaw UK for legal materials, government websites for formal documents, and some UK-based associations. Keyword searches were followed and the essential parts from the articles and documents were generalised for the analysis and discussion. Results : Issues over TM of East Asia include identity as medicine, efficacy and safety, and the statutory regulation can be a measure for the acceptance. Osteopathy and chiropractic therapies came under statutory regulation among the CAM in the UK. Conclusions : TM of East Asia could be under the statutory regulation in the near future. Efficacy and safety issues are the challenging barrier. However, the approach from the viewpoint of TM of East Asia is necessary for development and good practice. The simplified registration procedure for traditional herbal medicinal product in EU can be the model. Education, evaluation, assessment and managing quality of practice are essential for the standard care and formal regulation.

• Journal of Food Hygiene and Safety
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• v.27 no.4
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• pp.325-331
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• 2012

Food allergy refers to an immunologically mediated adverse reaction to food, mainly to proteinaceous constituents. Health implications vary between those individuals who experience mild physical discomforts to those with fast-acting, life-threatening anaphylactic reactions. The prevalence of food allergy is higher in children than in adults, estimated around 4-8% and 1-2% respectively in developed countries. Food allergy has no effective cure at the present time and total avoidance of causative foods is the most reliable prophylactic method currently recommended by the medical community. To help food allergic patients to make informed choices of their foods, mandatory labeling of selected food allergens has been introduced in several countries. All food allergen labelling provisions specify a set of allergens common to the regulated countries. Policy divergence, however, exists between countries by inclusion of additional allergens unique to specific countries and enforcement of specific labelling requirements. Such variations in food allergen labelling regulations make it difficult to manage allergen labeling in imported pre-packaged food products. This paper addresses two current issues in food allergen regulation: 1) an urgent need to determine true prevalence of food allergy in the Asia-Pacific region. This will enable refinement to the food allergen regulation to be more country-specific rather than simply adopting CODEX recommendations. 2) There is an urgent need for harmonization of food allergen regulation in order to prevent food allergen regulation becoming a trade barrier.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.169-172
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• 2008

This paper is a report of designing for high efficient LED lights driver. The main purpose of driver designing is meet the requirement the high efficient energy regulation for light of Korea. To meet the regulation the high efficient, the circuit adapted wide range resonant power supply and current regulate circuit to adjust LED current. This product archived excellent performance as well as reliable operation.

• Proceedings of the KIPE Conference
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• 2019.07a
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• pp.467-468
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• 2019

This paper proposes an improved bus voltage regulation scheme in filter-based reference current generation of power management for DC home grid with photovoltaics (PV), battery, and ultracapacitor (ultracap) by using feedforward terms instead of the filter output to produce the ultracap reference current. Simulation results have proved the effectiveness of the proposed scheme.

• IMMUNE NETWORK
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• v.9 no.4
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• pp.115-121
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• 2009

Natural killer (NK) cells play key roles in innate and adaptive immune defenses. NK cell responses are mediated by two major mechanisms: the direct cytolysis of target cells, and immune regulation by production of various cytokines. Many previous reports show that the complex NK cell activation process requires de novo gene expression regulated at both transcriptional and post-transcriptional levels. Specialized un-translated regions (UTR) of mRNAs are the main mechanisms of post-transcriptional regulation. Analysis of posttranscriptional regulation is needed to clearly understand NK cell biology and, furthermore, harness the power of NK cells for therapeutic aims. This review summarizes the current understanding of mRNA metabolism during NK cell activation, focusing primarily on post-transcriptional regulation.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.60 no.3
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• pp.126-132
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• 2011

A conventional LDO(Low Dropout Regulator) uses one OPAMP and one signal path. This means that OPAMP's DC Gain and Bandwidth can't optimize simultaneously within usable power. This also appears that regulation property and settling time of LDO can't improve at the same time. Based on this idea, a proposed LDO uses two OPAMP and has two signal path. To improve regulation property, OPAMP where is used in the path which qualities DC gain on a large scale, bandwidth designed narrowly. To improve settling time, OPAMP where is used in the path which qualities DC gain small, bandwidth designed widely. A designed LDO used 0.5um 1P2M process and provided 200mA of output current. A line regulation and load regulation is 12.6mV/V, 0.25mV/mA, respectively. And measured settling time is 1.5us in 5V supply voltage.

• Proceedings of the KIPE Conference
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• 1997.07a
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• pp.9-13
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• 1997

In this paper, the operation regions of a three-phase voltage-source PWM converter are defined: linear modulation region, allowed current region, linear control region, unity power-factor region, and power-factor decreasing region. Particularly, the power-factor decreasing region is first examined and defined as the region where both the sinusoidal input current control and the stable DC link voltage regulation can not be obtained with a unity power-factor operation. To avoid these undesirable effects, the optimal current vector is derived, which ensures the sinusoidal input current and the stable DC link voltage regulation with maximum power-factor available, and, in consequence, it extends the operation region of the PWM converter. The validity of the proposed control scheme is proved by the computer simulation.

• Journal of Power Electronics
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• v.7 no.4
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• pp.310-317
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• 2007

In this paper, an analysis and hysteretic controller design of a $3^{rd}$ order buck converter is presented. The proposed hysteretic controller consists of an inner current-loop, just like the conventional cascade control scheme, and an outer voltage-loop for load voltage regulation. Although it is possible to include an inner current loop from different branches of the converter, from the feasibility and operational point of view, the load side capacitor current would be the better choice. The addition of an inner current-loop improves the dynamic performance of the converter while preserving the robustness of the hysteretic control. The controller formulation and closed-loop converter performance analysis are validated through computer simulations. Few experimental results of the proposed converter are given and compared with the buck converter.