• The Journal of Korean Academy of Prosthodontics
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• v.21 no.1
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• pp.9-26
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• 1983

In order to investigate the biocompatibility of silver-palladium alloys, gingival fibroblast was obtained from a healthy human gingival and cultured in MEM medium with the addition of silverpalladium alloys. Four different mixture of silver-palladium alloys comprising of Ag-Pd-Au, Ag-Pd-In and Ag-Sn were tested. Results were assessed by calculating the cell multiplication rate per millimeter of medium and morphological changes in cells were also observed and noted.The obtained results were as follows; 1. Ag-Pd-Au alloy was indicated to be most biocompatible with gingival fibroblast. Also there was a decrease in cytotoxicity of the alloy as the concentration of gold increased. 2. Ag-Pd alloy showed a decrease in cell multiplication rate as compared to Ag-Pd~Au alloy. 3. Silver-palladium alloy supplemented with Indium increased the cell multiplication rate. 4. Among the alloys tested, Ag-Sn alloy was indicated to be the most cytotoxic and the least biocompatible with human gingival fibroblast.

• Applied Chemistry for Engineering
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• v.20 no.1
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• pp.104-108
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• 2009

In this study, for the flow of carbon dioxide/hydrogen mixture through a tubular type Pd-Ag membrane, hydrogen partial pressure, velocity profile, and concentration profile were simulated as a function of inlet flow rate using computational fluid dynamics (CFD) technique. The simulation results indicated that the mole fraction of carbon dioxide increased slowly in the longitudinal direction as the flow rate increased. In addition, the effects of inlet flow rate and the length of membrane on hydrogen recovery were investigated. At lower flow rate and for longer membrane, the hydrogen recovery was larger.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.4
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• pp.247-252
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• 1999

In this paper, in order to investigate availability of the OW-PD measurement method which has been proposed as an alternative of AC-PD measurement method to an after laying test and/or diagnosis for the power cable system, partial discharges owing to the needle-type defect integrated into the cable have been measured using AC and OW(Oscillating Wave) voltages. In the AC-PD measurement, the magnitude, phase and pulse number of partial discharges have been changed with the duration of voltage application, which can be analyzed through the relation with the process of the electrical tree initiation and propagation. In addition, the characteristics of partial discharges using OW voltage are appeared to be similar to those in case of AC-PD measurement and to be different with the shapes of electrical tree. From these results, it is concluded that the OW-PD measurement method is available to the tests for the cable system.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.2
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• pp.227-232
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• 2021

In this paper, the narrow-band characteristic, which is the disadvantage of the existing the PD sensor, was improved by transforming the sensor shape into a trapezoidal shape to improve the characteristics of the dipole-shaped conventional PD(Patial Discharge) sensor. In addition, by applying a cavity structure, which is a structure that can fundamentally block the electromagnetic wave signal from the outside as it is used for an external sensor, it is a partial discharge sensor that takes advantage of the structural advantages of low cost and convenience of installation. As a result of the experiment, it was shown that there is a broadband characteristic of about 70.5%(1.59~3.32GHz) at the center frequency of 2.45GHz, and the broadband characteristic was confirmed.

• Molecules and Cells
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• v.44 no.5
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• pp.363-373
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• 2021

Immune checkpoint inhibitors have changed the paradigm of treatment options for non-small cell lung cancer (NSCLC). Monoclonal antibodies targeting programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) have gained wide attention for their application, which has been shown to result in prolonged survival. Nevertheless, only a limited subset of patients show partial or complete response to PD-1 therapy, and patients who show a response eventually develop resistance to immunotherapy. This article aims to provide an overview of the mechanisms of acquired resistance to anti-PD-1/PD-L1 therapy from the perspective of tumor cells and the surrounding microenvironment. In addition, we address the potential therapeutic targets and ongoing clinical trials, focusing mainly on NSCLC.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.117-121
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• 2018

As the paradigm shifts in the era of accelerated technological development and technology convergence, the defense sector is pursuing national defense research and development through selection and concentration, as well as the expansion of investments to develop defense science and technology to the highest possible level. In addition to investing heavily in cutting-edge weapons and core technologies that are consistent with the future, the defense sector is also developing investment strategies within a limited budget. In the private sector, the PD system has been introduced in order to maximize the performance of R&D policy and to improve the professionalism and responsibility of planning & management. In accordance with this trend, in the field of defense, the PD system of defense technology with specialization is being promoted, in order to strengthen the task planning capacity and to promote the utilization of private technology. Considering the need for coherent technical support for the core technology developed by R&D, the improvement of open technology planning systems and expansion of inter-civil & technical linkage, the use of the PD system in the defense field is indispensable. In this study, we review similar cases abroad and at home to examine the introduction and management of the PD system for defense technology. This study is based on the current state of the defense technology PD system that is being pursued.

• Applied Chemistry for Engineering
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• v.28 no.5
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• pp.547-553
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• 2017

This study focused on the difference of photocatalytic performance by the incorporation of Pd into the $TiO_2$ framework and suggested five different catalysts composed of $TiO_2$ and x mol% $Pd-TiO_2$ (x = 0.25, 0.5, 0.75, and 1.0). A typical sol-gel method was used to synthesize catalysts, and the phenol photodegradation performance of each catalysts was evaluated. The physicochemical and optical properties of catalysts were confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy/energy dispersive spectrometer (SEM/EDS), ultraviolet/visible spectroscopy (UV/Vis), photoluminescence spectroscopy (PL), and photocurrent measurements. With the addition of Pd ions, the band gap of catalysts was shortened and the charge separation between photogenerated electrons and holes easily also occurred. As a result, the phenol photo-destruction performance over 0.75 mol% $Pd-TiO_2$ catalyst was 3 times higher than that of pure $TiO_2$. This is believed to be due to Pd ions acted as an electron capturing function during photocatalysis.

• Korean Journal of Optics and Photonics
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• v.34 no.4
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• pp.139-150
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• 2023

Despite various light detection and ranging (LiDAR) architectures, it is very difficult to achieve long-range detection and high resolution in both vertical and horizontal directions with a wide field of view (FOV). The scanning architecture is advantageous for high-performance LiDAR that can attain long-range detection and high resolution for vertical and horizontal directions. However, a large-area photodetector (PD), which is disadvantageous for detection speed, is essentially required to secure the wide FOV. Thus we propose a PD based on the static unitary detector (STUD) technique that can operate multiple small-area PDs as a single large-area PD at a high speed. The InP/InGaAs STUD PIN-PD proposed in this paper is fabricated in various types, ranging from 1,256 ㎛×949 ㎛ using 32 small-area PDs of 1,256 ㎛×19 ㎛. In addition, we measure and analyze the noise and signal characteristics of the LiDAR receiving board, as well as the performance and sensitivity of various types of STUD PDs. Finally, the LiDAR receiving board utilizing the STUD PD is applied to a 3D scanning LiDAR prototype that uses a 1.5-㎛ master oscillator power amplifier laser. This LiDAR precisely detects long-range objects over 50 m away, and acquires high-resolution 3D images of 320 pixels×240 pixels with a diagonal FOV of 32.6 degrees simultaneously.

• Journal of the Microelectronics and Packaging Society
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• v.20 no.3
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• pp.53-57
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• 2013

Although the lowering of Ag content in Sn-3.0Ag-0.5Cu is known to improve the mechanical shock reliability of the solder joint, it is also known to be detrimental to the solderbility. In this study, the quaternary alloying effect of In and the minor alloying effects of Mn and Pd on the solderability, thermal cycling and mechanical shock reliabilities of the low Ag content Sn-1.2Ag-0.7Cu solder were investigated using board-level BGA packages. The solderability of Sn-1.2Ag-0.7Cu-0.4In was proved to be comparable to that of Sn-3.0Ag-0.5Cu but its thermal cycling reliability was inferior to that of Sn-3.0Ag-0.5Cu. While the 0.03 wt% Pd addition to the Sn-1.2Ag-0.7Cu-0.4In decreased the solderability and reliabilities of solder joint, the 0.1 wt% Mn addition was proved to be beneficial especially for the mechanical shock reliability compared to those of Sn-3.0Ag-0.5Cu and Sn-1.0Ag-0.5Cu compositions. It was considered to be due that the Mn addition decreased the Young's modulus of low Ag content Pb-free solders.

• Korean Journal of Biological Psychiatry
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• v.25 no.3
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• pp.45-52
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• 2018

Objectives The objective of this study was to investigate the differences in sociodemographic and clinical characteristics, temperaments, and quality of life between panic disorder (PD) patients with and without major depressive disorder (PD+MDD and PD-MDD patients, respectively). Methods We compared 411 PD-MDD and 219 PD+MDD patients. All patients who were drug-free for at least 1 month were assessed at initial outpatient visits before the administration of medication. The following instruments were used for assessment: the NEO Personality Inventory-Neuroticism (NEO-N) ; the Temperament and Character Inventory-Harm Avoidance (TCI-HA) ; the State-Trait Anxiety Inventory (STAI) ; the Intolerance of Uncertainty Scale-Short (IUS); the Anxiety Sensitivity Index-Revised (ASI-R); the Beck Depression Inventory (BDI) ; the Beck Anxiety Inventory (BAI); the Penn State Worry Questionnaire (PSWQ) ; the Generalized Anxiety Disorder for 7 item (GAD-7) ; the Albany Panic and Phobia Questionnaire (APPQ) ; the Panic Disorder Severity Scale (PDSS) ; the Early Trauma Inventory Self Report-Short Form (ETISR-SF) ; the Scale for Suicidal Ideation (SSI) ; the World Health Organization Quality of Life Scale Abbreviated Version (WHOQOL-BREF) ; the Sheehan Disability Scale (SDS) ; and the Short Form health survey (SF-36). Results Compared to the PD-MDD patients, the PD+MDD patients were younger and more likely to be unmarried. They showed higher rates of unemployment, lower levels of education and income, younger age of onset, more previous suicide attempts, a greater incidence of agoraphobia, and more previous treatments. The PD+MDD patients showed significantly higher scores on the NEO-N, the TCI-HA, the STAI, the IUS, the ASI-R, the BDI, the BAI, the PSWQ, the GAD-7, the APPQ, the PDSS, the ETISR-SF, and the SSI. In addition, the PD+MDD patients showed significantly lower quality of life than did the PD-MDD patients. In contrast with previous studies, we observed no significant differences between the two groups in terms of gender, duration until treatment, and psychiatric comorbidities. Conclusions This study showed that the PD+MDD patients have more early trauma experiences, higher levels of anxiety-related temperaments, more severe panic and depressive symptoms, and lower quality of life than the PD-MDD patients.