• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.3
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• pp.33-42
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• 2003

This paper describes an efficient design of an asynchronous 16-bit divider using the NST (new Svoboda-Tung) algorithm. The divider is designed to reduce power consumption by using the asynchronous design scheme in which the division operation is performed only when it is requested. The divider consists of three blocks, i.e. pre-scale block, iteration step block, and on-the-fly converter block using asynchronous pipeline structure. The pre-scale block is designed using a new subtracter to have small area and high performance. The iteration step block consists of an asynchronous ring structure with 4 division steps for area reduction. In other to reduce hardware overhead, the part related to critical path is designed by a dual-rail circuit, and the other part is done by a single-rail circuit in the ring structure. The on-the-fly converter block is designed for high performance using the on-the-fly algorithm that enables parallel operation with iteration step block. The design results with 0.6${\mu}{\textrm}{m}$ CMOS process show that the divider consists of 12,956 transistors with 1,480 $\times$1,200${\mu}{\textrm}{m}$$^2$area and average-case delay is 41.7㎱.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.11
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• pp.1259-1268
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• 2010

In this paper, we presented a new LC prototype synthesis method for the multi-band filter. For synthesis a multi-band filter with the required frequency response, we proposed the diagram of poles and zeros, also, we proposed the optimization process for finding the combination of optimized poles and zeros. From the transfer and reflection functions calculated from poles and zeros, we performed the quasi-elliptic LC prototype synthesis of multi-band filter. Using the proposed LC prototype synthesis method of multi-band filter, dual-band filter operating at GSM(880~960 MHz) and ISM(2,400~2,500 MHz) and triple-band filter operating at GSM(880~960 MHz) and ISM(2,400~2,500, 5,725~5,850 MHz) were designed and fabricated.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.2
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• pp.98-111
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• 2008

This review introduces advances in clinical and pre-clinical single photon emission computed tomography (SPECT) and positron emission tomography (PET) providing noninvasive functional images of biological processes. Development of new collimation techniques such as multi-pinhole and slit-slat collimators permits the improvement of system spatial resolution and sensitivity of SPECT. Application specific SPECT systems using smaller and compact solid-state detector have been customized for myocardial perfusion imaging with higher performance. Combined SPECT/CT providing improved diagnostic and functional capabilities has been introduced. Advances in PET and CT instrumentation have been incorporated in the PET/CT design that provide the metabolic information from PET superimposed on the anatomic information from CT. Improvements in the sensitivity of PET have achieved by the fully 3D acquisition with no septa and the extension of axial field-of-view. With the development of faster scintillation crystals and electronics, time-of-flight (TOF) PET is now commercially available allowing the increase in the signal-to-noise ratio by incorporation of TOF information into the PET reconstruction process. Hybrid PET/SPECT/CT systems has become commercially available for molecular imaging in small animal models. The pre-clinical systems have improved spatial resolution using depth-of-interaction measurement and new collimators. The recent works on solid state detector and dual modality nuclear medicine instrumentations incorporating MRI and optical imagers will also be discussed.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.8
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• pp.151-161
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• 2013

An active power factor correction (PFC) circuit is presented which employs a newly proposed input voltage sensor-less control technique operated in continuous conduction mode (CCM) and critical conduction mode (CRM). The conventional PFC circuit with input voltage sensor-less control technique degrades the power factor (PF) under the light load condition due to DCM operation. In the proposed PFC circuit, the switching frequency is basically 70KHz in CCM operation. In light load condition, however, the PFC circuit operates in CRM and the switching frequency is increased up to 200KHz. So CCM/CRM operation of the PFC circuit alleviates the decreasing of the PF in light load condition. The proposed PFC controller IC has been implemented in a $0.35{\mu}m$ BCDMOS process and a 240W PFC prototype is built. Experimental results shows the PF of the proposed PFC circuit is improved up to 10% from the one employing the conventional CCM/DCM dual mode control technique. Also, the PF is improved up to 4% in the light load condition of the IEC 61000-3-2 Class D specifications.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.7
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• pp.37-43
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• 2010

As the speed of A/V streaming, the transmission-speed requirement of serial link is continuously increasing. Consequently, commercial standards, which are released previously, are increasing transmission speed in their newly-updated versions. The flexibility between previous and updated versions is very important requirement, therefore, the transceiver which can operates at more than one data rate is important market demand. This paper demonstrates 4-channel 3.2/ 6.4 Gbps transmitter, which is capable of selecting 1, 1.5, 2, and 3 times of pre-emphasis and 200, 300, 400, and 600 mVdiff,p2p of output swing. The prototype chip was fabricated using $0.13{\mu}m$ CMOS process. Its performances are verified on PCB using COB packaging.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.27-36
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• 2018

Financial IT evaluation methods have been unable to satisfy firms' requirements. There has been a growing demand for more comprehensively and non-financially measuring the IT performance. We developed a process-based approach in evaluating impacts of IT on primary activities. In this research we proposed a model that uses the corporate objective of IT and strategic fitt as the core independent variables in measuring the IT effect. Based on the data collected from the management variables of the 125 companies located in Korea, the companies were classified into the 4 different groups according to their corporate objective for IT: un-oriented, operations oriented, market oriented and dual oriented. Through the empirical analysis, we were able to demonstrate that the management of the companies showing a higher orientation level perceives a better IT investment performance, and this shows that the corporate objective for IT serves as a useful index for measuring the IT investment effect. In this research, it was also demonstrated that the strategic alignment has a positive influence on perceiving the IT investment effect.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.4
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• pp.319-329
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• 1989

The present paper mainly cocerns, in social aspect of the cultural change, with how cholik was introduced and accepted in $Kory\v{o}$ dynasty. It was through cultural transmission in political relations with Won dynasty that $ch\v{o}$ lik was first listed on our own costume system in later $Kory\v{o}$ dynasty. The acceptance by $Kory\v{o}$ society can be interpreted as the twofold effects; positively, it enriched our costume system and, negatively, it brought about various conflicts, which in turn caused some unwelcome reactions. Once it had permeated into $Kory\v{o}$ culture. it could not avoid being changed by social conditions. The changing process can be defined as the dual cycles of fashion. The first one startd at mid peroid of $Kory\v{o}$ when King $Chung-ry\v{o}$l provided a law to wear the $W\v{o}n$ costume and. ended at larter $Kory\v{o}$ of King Kong-min's reign. The second cycle rose in the period between King Sejong's reign and late $Chos\v{o}n$. Each of the two cycles appeared to have its own characteristics; 1. The first cycle. 1) In spite of the long period of a century, the cycle was very abrupt both in development and decline. 2) The abrupt pattern of the cycle can be attributed to the nation-wide law provided by the ruler. 2. The second cycle. 1) Compared with the first cycle, the curve was rather slow. 2) The fashion originated from the hyperimitation of the government officials, since the costume was the royal gift by Chinese Emperor. 3) The main cause of the development of the fastion was the wars, rather than the public preference. 4) The main cause of the decline of the fashion was that it could no more differentiate the social status, that the wearer was laughed at by the Chinese, and that the long period of wearing the same dress stimulated the fashion psychology. 5) The increasing size of the costume rather decreased the very function of the costume.

• Proceedings of the Korean Society for Language and Information Conference
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• 2001.06a
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• pp.237-257
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• 2001

This paper investigates the idiosyncratic understanding of universal quantifiers such as every, each or all by young children at the ages of 4 to 7, and argues that the phenomenon is explicable in terms of the maturation of both the cognitive system and the linguistic system. Evidence for this dual explanation comes from the fact that the visual input, a picture, plays a key role in determining the children’s conceptual representation, suggesting the need for the central integration of visual and linguistic elements; and from the fact that a quantifier in the linguistic input has an intrinsic property, i.e. a <+focus> feature. I have tried to explain the nature of the cognitive factors in terms of the function of the central system, suggesting a modified form of Smith & Tsimpli’s (1995) version of Fodor’s (1983) modularity hypothesis. Conceptual representations of two kinds are in competition with each other and they are integrated into a neutral LOT (Language of Thought) representation at some point . In the process of this integration, the representations from the visual input predominate over those from the auditory input, though the quantize. (treated as new information provided by the latter) is salient in the final representations. When visual conceptual representations predominate over purely linguistic ones, quantifier spreading errors occur. By contrast, when the relevant grammatical knowledge has developed sufficiently to counteract the conceptual representations, this peculiar behaviour by children should disappear. It is argued that children have to learn two kinds of grammatical fact with regard to universal quantification: (i) they have to learn the status of the quantifier as a functional head of DP so that it has to be positioned inside DP; and (ii) they have to learn the Left-Branch Condition which specifies that movement of an element in the left-branch position is possible only by pied-piping the entire phrase.

• Korean Institute of Interior Design Journal
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• v.24 no.2
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• pp.58-66
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• 2015

This study was conducted to determine a 'platform' as a mean of interactions between users in contemporary spatial design and network(web) and to verify the similarity between the platform and space of Rem Koolhaas, one of the leading contemporary architects of our time. A platform, referring to tangible or intangible structures designed for common use in a variety of ways, is activated by the networking effect of participants. Aided by the recent development of the IT industry encompassing computers and smart phones, the concept of platforms is extending to all areas of modern life, in general. In this study, the similarity between architectural space and platforms after reviewing the computer-related platforms, ecological features that refer to virtuous circulation, and various cases applied with platform thinking. Through this process, the platform feature of architectural platforms is defined as the 'open spatial system combined with control and freedom that acts more than one function and facilitates direct/indirect exchanges between users regardless of its type or size'. Establishing the criteria for spatial analysis based on this definition, analysis was conducted on interior design projects that were planned and conducted by Rem Koolhaas after 2000. As a result of this analysis, it was learned that Rem Koolhaas designs space using dual space structures where the extension and mixture of the user group, mixture of various functions defined by users, loose control that induces voluntary participation, community reinforcement, and inducement of accidental events, and opening and closing coexist. In addition, this design approach was found to be a design strategy similar to the concept of platforms that began to be developed in the IT field.

• Journal of IKEEE
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• v.24 no.3
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• pp.853-858
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• 2020

This paper proposes a 2-ch DC-DC converter for OLED display with immunity against RF noise inserted from communication device. For RF signal immunity, an input voltage variation reduction circuit that attenuates as much as the input voltage variation is embedded. The boost converter for positive voltage V_POS operates in SPWM-PWM dual mode and has a dead time controller to increase power efficiency. The inverting charge pump for negative voltage V_NEG is a 2-phase scheme and operates in PFM using VCO to reduce output ripple voltage. Simulation results using 0.18 ㎛ BCDMOS process show that the overshoot and undershoot of the output voltage decrease from 10 mV to 2 mV and 5 mV, respectively. The 2-ch DC-DC converter has power efficiency of 39%~93%, and the power efficiency of the boost converter is up to 3% higher than the conventional method without dead time controller.