• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.4
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• pp.787-794
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• 1999

This paper presents an ENMODL(enhances NORA MODL) circuit and implements a high-speed 32 bit CLA(carry lookahead adder) with the new dynamic logics. The proposed logic can reduce the area and the Propagation delay of carry because output inverters and a clocking PMOS of second stage can be omitted in two-stage MODL(multiple output domino logic) circuits. The 32-bit CLA is implemented with 0.8um double metal CMOS Process and the carry propagation delay of the adder is about 3.9 nS. The ENMODL circuits can improve the performance in the high-speed computing circuits depending on the degree of recurrence.

• Structural Engineering and Mechanics
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• v.17 no.3_4
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• pp.445-466
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• 2004

In this paper, several modal identification techniques for output-only structural systems are extensively investigated. The methods considered are the power spectral method, the frequency domain decomposition method, the Ibrahim time domain method, the eigensystem realization algorithm, and the stochastic subspace identification method. Generally, the power spectral method is most widely used in practical area, however, the other methods may give better estimates particularly for the cases with closed modes and/or with large measurement noise. Example analyses were carried out on typical structural systems under three different loading cases, and the identification performances were examined throught the comparisons between the estimates by various methods.

• Journal of Biomedical Engineering Research
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• v.10 no.3
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• pp.279-284
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• 1989

Measurement of cardiac output during exercise by noninvasive technique is very needed in the area of sports medicine. However there are only two noninvasive techniques, one of which is $CO_2$ subscript rebreathing technique and the other one is impedance cardiography. While $CO_2$ rebreathing technique needs special breathing and metablic steady state, impedance cardiography has motion Uiiau problem. In this study maior sources of the mothion artifact during treadmill exercise was found experimentally to. be the impact caused by each step on the treadmill. Thus special shoes to reduce the impact were developed. These are the shoes with silicon rubber and hard sponge attached to the soles. It was possible to measure cardiac output with the newly developed shoes for Burke protocol whose speed of the treadmill was constant 3.5 miles/hour while it was impossibel with the conventional exercise shoes.

• Journal of the Korean Operations Research and Management Science Society
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• v.23 no.3
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• pp.75-90
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• 1998

The improper use of input and output factors in DEA has a critical and negative impact on the efficiency measurement and the discernment of decision making units(DMUs) : hence the proper selection Process of the factors should precede the actual applications of DEA. In this paper, we propose a new approach to selecting proper factors based on Tofallis' partial efficiency evaluation method(1996). With the approach, the factors aye clustered by measuring their respective partial efficiencies and analyzing the rank correlations of them. The method and procedure we propose in this paper are then applied to measure the efficiencies of the public libraries in Seoul District area, and the results show that the proposed approach can provide meaningful information to improve discernment of the DMUs while using less number of input factors (and less information). The proposed method can be effectively used in the situation where the number of the DMUs to be considered is relatively small compared to the number of available input and output factors, which usually lessens the power to identify the inefficient units in DEA.

• ETRI Journal
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• v.37 no.5
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• pp.972-978
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• 2015

This paper proposes an accurate tunable-gain 1/x circuit. The output voltage of the 1/x circuit is generated by using a capacitor charging time that is inversely proportional to the input voltage. The output voltage is independent of the process parameters, because the output voltage depends on the ratios of the capacitors, resistors, and current mirrors. The voltage gain of the 1/x circuit is tuned by a 10-bit digital code. The 1/x circuit was fabricated using a $0.18{\mu}m$ CMOS process. Its core area is $0.011mm^2$ ($144{\mu}m{\times}78{\mu}m$), and it consumes $278{\mu}W$ at $V_{DD}=1.8V$ and $f_{CLK}=1MHz$. Its error is within 1.7% at $V_{IN}=0.05V$ to 1 V.

• ETRI Journal
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• v.42 no.5
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• pp.790-798
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• 2020

Herein, a low-ripple coarse-fine digital low-dropout regulator (D-LDO) without ringing in the transient state is proposed. Conventional D-LDO suffers from a ringing problem when settling the output voltage at a large load transition, which increases the settling time. The proposed D-LDO removes the ringing and reduces the settling time using an auxiliary power stage which adjusts its output current to a load current in the transient state. It also achieves a low output ripple voltage using a comparator with a complete comparison signal. The proposed D-LDO was fabricated using a 65-nm CMOS process with an area of 0.0056 μ㎡. The undershoot and overshoot were 47 mV and 23 mV, respectively, when the load current was changed from 10 mA to 100 mA within an edge time of 20 ns. The settling time decreased from 2.1 ㎲ to 130 ns and the ripple voltage was 3 mV with a quiescent current of 75 ㎂.

• Journal of Electrical Engineering and Technology
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• v.2 no.1
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• pp.29-34
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• 2007

The input and output impedances in a low voltage distribution system is one of the most important matters for power line communication because from the viewpoint of communication, the attenuation characteristic of the high frequency signals is greatly caused by impedance mismatch during sending and receiving. The frequency range is from 1MHz to 30MHz. Therefore, this paper investigates the input and output impedances in order to understand the characteristic of high frequency signals in the low voltage distribution system between a pole transformer and an end user. For power line communication, the model of Korea's low voltage distribution system is proposed in a residential area and then the low voltage distribution system is set up in a laboratory. In the low voltage distribution system, S parameters are measured by using a network analyzer. Finally, input and output impedances are calculated using S parameters.

• Journal of the Korean Society for Library and Information Science
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• v.16
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• pp.243-279
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• 1989

Public library effectiveness is determined by a complexity of the internal and external environments of the library. The purpose of this article is to investigate community environments and library resources as determinants of the output measures of the 15 municipal libraries in Seoul and to cope with changes in the environments for the improvement of their performance. This study is based on the hypotheses that the library's output would be proportioned to the size of budget and library collection, and to the relationships between the characteristics of the library and of the community in which the library develops. The variables identified in this .study are population density, family size, institutions (social, cultural, financial and educational), presence of the mass media, size of service area, and economic level of the community. The output measures employed for analysis are: number of professional staff, expenditures, number of books in the collection, number of books added annually, total circulation, number of library visits, circullation per capita, library visits per capita, .and registration as a percentage of population. The recommendation made in this study is the innovation of the 15 libraries in organization.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.3
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• pp.357-363
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• 1986

In the design of PLA's of VLSI, as the number of subsets of functions from which common preme implicants must be determined increases, the execution time increases by a factor of O(2\ulcorner. When the number of functions N is a large number, this poses a serious problem in minumization of multiple-output logic functions. In this paper a new algorithm that minimizes multiple-output logic functions is proposed. The algorithm requires less number of Fortran statements, less execution time, and less memory area than existing methods. The bases of this algorithm are explained and verified, and the sequential operation for preparation of the program is discussed.

• Proceedings of the IEEK Conference
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• 2003.07d
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• pp.1243-1246
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• 2003

It is known that structure of Human's brain information system is controlled by cerebral cortex mainly. Cerebral cortex is divided by sensory area, motor area and associated area largely. Sensory area takes part in information from environment and motor area is actuation by decision as associated area determined. It is possible to copy brain information system by input-output pattern. but there is difficulty in modeling of memorizing new information. Such action is performed by Limbic Lobe and Papez circuit which is controlled by intrinsic emotion. So we need of definition of emotion's role in decision. In this paper, we define roles of emotion in intrinsic decision using Dynamic Cognitive Maps(DCMs). The emotion is evaluated by outside information then intrinsic decision performed as how much emotion variated. The dynamic cognitive maps take part in emotion evaluating process.