• Journal of Korea Foundry Society
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• v.26 no.4
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• pp.184-190
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• 2006

Presence of inclusions in Ti castings imparts detrimental effects on the mechanical performance of castings. However, actual inclusions do not occur very frequently and they are difficult to locate. As a result, acquirement of specimens for mechanical tests and thus in-depth research of the adverse influence of inclusions are challenging. To address this problem, artificial inclusion seeding methodology is developed to emulate actual inclusions in Ti investment castings. Firstly, to validate that this new methodology does not result in inherent mechanical property degradation, Ti specimens with machined, backfilled and HIPed holes are produced and compared to control (unaltered), cast Ti material. Fatigue test results indicate that this 'machine-and-HIP methodology without seeding' does not result in any fundamental mechanical property alteration, which would bias ensuing comparative results. Secondly, based on this result, validation of the artificially seeded inclusions being equivalent to 'as cast' inclusions is performed by comparing their fatigue behaviors. Test specimens created by the novel artificial inclusion seeding methodology are equivalent to Ti casting specimens containing actual cast-in inclusions, and an adverse effect of inclusions in investment castings is confirmed.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.1
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• pp.1-7
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• 2013

In this paper, a biosensor based on a gated lateral bipolar junction transistor (BJT) is proposed. The gated lateral BJT can function as both a metal-oxide-semiconductor field-effect transistor (MOSFET) and a BJT. By using the self-assembled monolayer (SAM) method, the C-reactive protein antibodies were immobilized on the floating gate of the device as the sensing membrane. Through the experiments, the characteristics of the biosensor were analyzed in this study. According to the results, it is indicated that the gated lateral BJT device can be successfully applied as a biosensor. Additionally, we found that the sensitivity of the gated lateral BJT can be varied by adjusting the emitter (source) bias.

• Journal of Korean Medicine Rehabilitation
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• v.30 no.4
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• pp.105-117
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• 2020

Objectives The objective of this study is to assess the effectiveness of electroacupuncture for patients with hip arthroplasty. Methods According to participants, intervention, comparison, outcome, study design, we searched for clinical studies that conducted electroacupuncture for patients with hip arthroplasty. Results Finally 11 randomized controlled trials were chosen for systemic review and meta-analysis. The frequently used evaluation tools were Incidence of postoperative cognitive dysfunction (POCD), heart rate, blood pressure. Almost studies showed electroacupuncture has effects for patients with hip arthroplasty. Through meta analysis, Electoacupuncture showed statistically significant effect of reducing the anesthetic dosage and incidence of postoperative psychonosema and adverse reactions in intra-operation period, reducing the incidence of POCD in peri-operation period, incidence of deep venous thrombosis in post-operation period. Conclusion 11 studies reported that electroacupuncture has significant effects on hip arthroplasty. But, many studies were assessed in a probable high risk of bias. And all studies published in one overseas country. So, it requires attention to comprehend this study. To make up for this limitaion, more well designed clinical research are needed.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.3
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• pp.359-363
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• 2011

An orthogonal magnetic field is often used for a military vessel in the deperm process such as Flash D deperm protocol and Anhysteretic deperm protocol. The effect of the orthogonal magnetic field on a deperm performance was investigated for a sample with strain-induced magnetization and field-induced magnetization given to different direction. A 70mm wide, 110mm long and 0.25mm thick rectangular steel plate was bent to have U-shape and to generate a strong strain on the bottom region of U-shaped steel plate. Field-induced magnetization was attached by NdFeB permanent magnet. Demagnetization was performed by applying magnetic field with a step decrement from the first field(the first shot) under the action of DC bias field.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1025-1027
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• 2009

Novel low temperature deposition process for nano-crystalline Si thin film is developed with the hyper-thermal neutral beam (HNB) technology. By our HNB assisted CVD system, the reactive particles can induce crystalline phase in Si thin films and effectively combine with heating effect on substrate. At low deposition temperature under $80^{\circ}C$, the HNB with proper incident energy controlled by the reflector bias can effectively enhance the nano-crystalline formation in Si thin film without any additional process. The electrical properties of Si thin films can be varied from a-Si to nc-Si according to change of HNB energy and substrate temperature. Characterization of these thin films with conductivity reveal that crystalline of Si thin film can increase by assist of HNB with appropriate energy during low temperature deposition. And low temperature prcoessed nc-Si TFT performance has on-off ratio as order 5.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.329-332
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• 1999

In this paper, BST((Bao.&o,dTi0:3) thin films were deposited by the rf magnetron sputtering method on Pt/$SiO_2$/Si substrate. Pt, $RuO_2$, Ag, Cu films for the formation of top electrode were deposited on BST thm films. And then Top Electrodes/BST/Pt capacitors were annealed with rapid thermal annealing(RTA) at various temperature. We have investigated effect of post-annealing on the electrical properties such as dielectric constant and leakage current of the capacitors. It was found that electrical properties of the capacitors were greatly depended on the annealing temperatures as well as the materials of top electrodes. In BST thin films with Pt top electrode was annealed at $700^{\circ}C$. the dielectric constant was measured to the value of 346 at l[kHzl and the leakage current was obtained to the value of $8.76\times10^8$[A/$\textrm{cm}^2$] at the forward bias of 2[V].

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.222-223
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• 2006

In this paper, we manufactured high flux LED module with Through Hole type. and we measured electrical, optical and thermal properties by driving type. LED module was composed with 8*8 arrangement form by using the glass epoxy PCB. Also, we measured the most suitable driving type with static voltage driving type and static current driving type. As a result, the LED Module of static voltage driving type showed high luminance characteristic than the static current driving type by suppling enough bias. However, the static current driving type showed more stable driving properties because of fast decreasing properties about brightness by increasing the surrounding temperature in the static voltage driving type. Also, due to Quantum confined Stark effect from piezoelectric field, the wavelength of bule peak shifted to long wavelength direction by increasing the surrounding temperature in the static voltage driving type.

• Journal of the Korea Society of Computer and Information
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• v.19 no.2
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• pp.201-208
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• 2014

The objective of the present study is to investigate the relationships among the perceptions of performance appraisal politics(POPAP)), employee's attitude to work, and team-based work system characteristics. Using survey data from various occupationally heterogeneous sample of white-collar employees(N=195) from various organizations, the results indicate that when employees perceive performance rating to be manipulated because of rater's personal bias and punishment motive, they reduce organizational commitment. Contrarily, the employees' POPAP with motivational motive increases organizational commitment. And task interdependency has positive effect on employees' POPAP.

• Journal of Positioning, Navigation, and Timing
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• v.3 no.4
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• pp.155-161
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• 2014

The purpose of this study is to develop precise point positioning (PPP) algorithms based on GLONASS code-pseudorange, verify their performance and present their utility. As the basic correction models of PPP, we applied Inter Frequency Bias (IFB), relativistic effect, satellite antenna phase center offset, and satellite orbit and satellite clock errors, ionospheric errors, and tropospheric errors that must be provided on a real-time basis. The satellite orbit and satellite clock errors provided by Information-Analytical Centre (IAC) are interpolated at each observation epoch by applying the Lagrange polynomial method and linear interpolation method. We applied Global Ionosphere Maps (GIM) provided by International GNSS Service (IGS) for ionospheric errors, and increased the positioning accuracy by applying the true value calculated with GIPSY for tropospheric errors. As a result of testing the developed GLONASS PPP algorithms for four days, the horizontal error was approximately 1.4 ~ 1.5 m and the vertical error was approximately 2.5 ~ 2.8 m, showing that the accuracy is similar to that of GPS PPP.

• Journal of Contemporary Eastern Asia
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• v.16 no.2
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• pp.20-43
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• 2017

While the Internet has been used to galvanise people for the collective good, many have voiced concerns over the noise and vitriol present online and polarisation. In Singapore where the government regulates traditional mainstream media such as print and broadcast, the online space has been described as a "Wild Wild West" rife with rumours, untruths and misinformation. Such developments do not only exert a potential negative effect on the deliberative nature of public discourse but also skew bias towards the online space, affecting the ability of online users to communicate with authority and power. This study seeks to examine the rationality of the cyberspace through using a new "rationality" framework to analyse political discourse online. Comprising objectivity, emotionality and partisanship, the rationality framework was applied to a content analysis of 197 blogs with political content in 2014. The analysis indicated that the online political space was not the Wild Wild West that it was touted to be with significant levels of objectivity and non-partisanship. There was a stark absence of emotional discourse, and relationships were observed between bloggers' anonymity and rationality. Cognisant of academia's and policymakers' interest on the quality and effects of online discourse, the proposed analytical framework and the study findings hold implications for both developed and developing countries.