• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1730-1733
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• 2007

As semiconductor and MEMS devices become smaller, testing process during their production should follow such a high density trend. A circuit inspection tool "probe card" makes contact with electrode pads of the device under test (DUT). Nowadays, electrode pads are irregularly arranged and have height difference. In order to absorb variations in the heights of electrode pads and to generate contact loads, contact probes must have some levels of mechanical spring properties. Contact probes must also yield a force to break the surface native oxide layer or contamination layer on the electrodes to make electric contact. In this research, new vertical micro contact probe with bellows shape is developed to overcome shortage of prior work. Especially, novel bellows shape is used to reduce stress concentration in this design and stopper is used to change the stiffness of micro contact probe. Variable stiffness can be one solution to overcome the height difference of electrode pads.

• The Journal of the Korea Contents Association
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• v.16 no.10
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• pp.403-410
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• 2016

Dut to the development of information technology, various serious games have been provided. In recent years, educational serious game that provides education services haven't been widely used. Especially, using serious game without trust is one of the main hinderance in the expansion of educational serious games. Therefore, the purpose of this research is to investigate the impact of trustworthiness, which is antecedent variable for trust, on commitment and continuance intention. To achieve the research purpose, this study conduct the survey. The results showed that the trustworthiness significantly influence on commitment and continuance intention.

• Journal of Ginseng Research
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• v.14 no.3
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• pp.379-384
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• 1990

In order to study the lipid peroxidation caused by light and the protective action it in biological memberane, reverse-phase evaporation liposome (REV) was employed as a model memberance and the effect of several antioxidants and ginseng water extracts were tested. In the presence of photosensitizer, liposome was oxidized easily and the oxidation index dut to the peroxidation was increased. The oxidation index of liposome was increased according to the increase in temperature. When dl-${\alpha}$-tocopherol, ${\beta}$-carotene or L-ascorbic acid was added into the reaction mixture, the photooxidation of liposome was inhibited. Ginseng water extract and crude saponin inhibited the rate of oxidation index of liposome in low concentration but increase in high concentration. On the other hand, when lipid hydroperoxide of liposome was tested by ferrothiocyanate method, ginseng water extract and crude saponin acted as antioxidants.

• Korean Journal of Optics and Photonics
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• v.10 no.5
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• pp.419-423
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• 1999

Optical filters utilizing the evanescent filed coupling between the side polished fiber and polymer planar waveguide were fabricated and optical properties of the devices were measured. A scheme for reducing polarization dependent properties of the device was proposed and demonstrated experimentally. Our measurement results showed that resonance wavelengths and filtering depth of the optical filters can be determined by adjusting thickness of planar waveguide and polishing depth of the fiber. The device fabrication procedure including fiber polishing steps and formation of polymer planar waveguide were described. The optical characteristics of fabricated optical filers were that 3 dB bandwidth was 15 nm, the resonance wavelength difference between the TE and TM polarized response was less then 2 nm, and insertion loss was less then 0.2 dB. The measured resonance wavelength drift dut to the variation of ambient temperature was -0.35 nm/$^{\circ}C$.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.5
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• pp.1330-1336
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• 2005

This study was carried out to investigate the motor activity and glucose transport and metabolism of Gaewool-Whadam-Jian(GWJ) in rat gastro-intestinal tract. The motor activity of the rat gastro-intestinal tract has been investigated by means of measuring barium sulfate passage degrees. Atropine treatment significantly delayed barium sulfate transit, and GWJ pretreatment increased intestinal motor activity, but not significant. GWJ administration showed no toxicity to kidney and liver. Transport and metabolism of glucose were studied in everted sac of rat small intestine with incubation under several conditions. The transport and metabolism of glucose were greater at jejunum than ileum. So, everted jejunum of rat were used to study the effect of GWJ. When GWJ were treated, the concentration of glucose were higher than untreated group. This result was thought to be influenced by the glucose in GWJ. When 2, 4 dinitrophenol and phlorizin were treated, the transport and metabolism of glucose were decreased, but GWJ treated together, the concentration of glucose in serosal solution increased. Gastric juice secretion and total acidity significantly decreased by administration of GWJ through duodenum region. The mechanism of effect of GWJ was still unidentified, Dut through continuous investigation, the effect of GWJ should be investigated.

• Proceedings of the Korean Reliability Society Conference
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• 2004.07a
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• pp.239-246
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• 2004

Accelerated degradation test (ADT) can be a useful tool for assessing the reliability when few or even no failure are expected in an accelerated life test. In this paper, MLCC (Multilayer Ceramic Capacitors), a sort of passive components which have large capacitance(X7R -55$^{\circ}C$~1$25^{\circ}C$) have been tested, and least-square analyses are used to illustrate our approach in which amount of degradation of a DUT following log-normal distribution. We assumed a simple and useful linear model to describe the amount of degradation over time subjected to different voltage levels applied. Tests for linearity of the performance-time relationship, and provide tests for how well the assumptions hold. Also, by using Eyring Model, MLCC's mean life time is assessed.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.195-204
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• 2020

The aim of this study is to estimate the impact of ownership structure on the performance of listed firms in transition economy. Buiding upon agency theory, hypotheses on such relationship are proposed. A detailed panel data of 502 non-financial companies listed on Ho Chi Minh Stock Exchange and Hanoi Stock Exchange over the period from 2013 to 2018, and the system generalized method of moment estimation are employed to test the proposed hypotheses. To ensure the reliability of data, this study excludes companies that violate information disclosure regulations or that are subject to special supervision by the State Securities Commission of Vietnam. Some firms with inadequate information, firms that lack the financial data required for creating variable or firms that have inconsistent construction are also re-screened. We only collect the data of enterprises that have ownership structure of two or more components. Estimation results reveal that state ownership has an U-shaped relationship with the performance of Vietnamese listed firms, while foreign ownership and the degree of ownership concentration have an inverted U-shaped relationship with listed firms' performance. The article provides governance implications that Vietnamese listed firms should decrease state ownership and foreign ownership to improve firm performance in order to boost investors' confidence.

• IEIE Transactions on Smart Processing and Computing
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• v.4 no.4
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• pp.291-296
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• 2015

This paper describes the design of a high-speed comparator for high-speed automatic test equipment (ATE). The normal comparator block, which compares the detected signal from the device under test (DUT) to the reference signal from an internal digital-to-analog converter (DAC), is composed of a rail-to-rail first pre-amplifier, a hysteresis amplifier, and a third pre-amplifier and latch for high-speed operation. The proposed continuous comparator handles high-frequency signals up to 800MHz and a wide range of input signals (0~5V). Also, to compare the differences of both common signals and differential signals between two DUTs, the proposed differential mode comparator exploits one differential difference amplifier (DDA) as a pre-amplifier in the comparator, while a conventional differential comparator uses three op-amps as a pre-amplifier. The chip was implemented with $0.18{\mu}m$ Bipolar CMOS DEMOS (BCDMOS) technology, can compare signal differences of 5mV, and operates in a frequency range up to 800MHz. The chip area is $0.514mm^2$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.635-641
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• 2004

This paper presents a new low-cost RF Built-In Self-Test (BIST) circuit for measuring transducer voltage gain, noise figure and input impedance of 5.25GHa low noise amplifier (LNA). The BIST circuit is designed using 0.18${\mu}{\textrm}{m}$ SiGe technology. The test technique utilizes input impedance matching and output transient voltage measurements. The technique is simple and inexpensive. Total chip size has additional area of about 18% for BIST circuit.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.699-707
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• 2021

The objective of this study is to examine the determinants of the liquidity of 17 commercial banks listed on the Vietnamese Stock Exchanges, HOSE, HNX and UPCoM. The study uses the quarterly audited financial statements from the first quarter of 2006 to first quarter of 2020; it includes 496 observations. Data on GDP and inflation are compiled from the International Monetary Fund and the General Statistics Office of Vietnam. Once collected, the data were organized along the line of unbalanced panel data. The results show that total asset size, return on total assets, and credit growth are positively associated with the liquidity of the listed banks; whereas the interaction between the bank size and the return on total assets has a negative impact on the liquidity of commercial banks listed on the HNX, HOSE, UPCoM. In order to maintain good liquidity, commercial banks need to focus on effective credit growth, ensure a high rate of profit over total assets, and at the same time focus on developing the scale of total assets. However, the development of the size of the total assets should be noted in the balance between the total assets and the rate of return on the total assets.