• Journal of the Microelectronics and Packaging Society
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• v.21 no.3
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• pp.43-50
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• 2014

By the trends of electronic package to be smaller, thinner and more integrative, the reliability of interconnection between Si chip and printed circuit board is required. This paper reports on a study of high speed shear energy of Sn-4.0wt%Ag-0.5wt%Cu (SAC405) solder joints with different the thicknesses of electroless Ni-P deposit. A high speed shear testing of solder joints was conducted to find a relationship between the thickness of Ni-P deposit and the brittle fracture in electroless Ni-P deposit/SAC405 solder. A focused ion beam (FIB) was used to polish the cross sections to reveal details of the microstructure of the fractured pad surface with and without $HNO_3$ vapor treatment. The high speed shear energy of SAC405 solder joint with $1{\mu}m$ Ni-P deposit was found to be lower without $HNO_3$ vapor, compared to those of over $3{\mu}m$ Ni-P deposit. This could be due to the edge of solder resist in $1{\mu}m$ Ni-P deposit, which provides a fracture location for the weakened shear energy of solder joints and brittle fracture in high speed shear test. With $HNO_3$ vapor, the brittle fracture mode in high speed shear test decreased with increasing the thickness of Ni-P deposit. Then the roughness (Ra) of Ni-P deposits decreased with increasing its thickness. Thus, this gives the evidence that the decrease in roughness of Ni-P deposit for Eelectroless Ni/ Electroless Pd/ Immersion Au (ENEPIG) surface play a critical role for improving the robustness of SAC405 solder joint.

• Food Science of Animal Resources
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• v.28 no.2
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• pp.218-221
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• 2008

The aim of this work was to establish the standard for goat milk somatic cell counts. The data were obtained from MGEN, which were collected from Dec. 2006 to Nov. 2007. A total of three hundred and forty somatic cell counts from 12 goat milk farms were analyzed. A goat milk grading system by somatic cell count is proposed; less than 1,000,000/mL, 1,000,000-1,500,000/mL, 1,500,000-2,000,000/mL, 2,000,000/mL-2,500,000/mL, and over 2,500,000/mL. Under the grading system, the ratio of first grade goat milk would be 26.2%, and that of the fifth grade would be 11.8%. The first grade ratio is low and the fifth grade ratio is high compared to the cow milk grading system. It is expected that somatic cell counts of domestic goat milk will be improved by the proposed grading system.

• Food Science of Animal Resources
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• v.28 no.1
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• pp.59-62
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• 2008

The aim of this work was to assess the Delvo test for the detection of antimicrobial residues in goat milk. A total of fifty six samples (eight farms, seven samplings each) were analyzed by the Delvo, Eclipse 100, and Parallux tests. None of the samples showed positive results with the Parallux test which is based on immune-chemical methods. However, 37.5% of samples showed positive results with the Delvo test. 3.6% of samples showed positive results with the Eclipse 100 test, which is based on a microbiological method. The Delvo test is included in the 'standard methods for the examination of raw milk' by the National Veterinary Research and Quarantine Service as a microbiological method used for the detection of antimicrobial residues. Because "raw milk" is defined as 'milked state of cow, ewe and goat milk for sale or for processing' in the Animal Food Products Processing Law, the Delvo test should be excluded from the 'standard method for the examination of raw milk', or additional official documents referring to the Delvo test as not appropriate for the detection of antimicrobial residues of goat milk are required.

• Economic and Environmental Geology
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• v.48 no.5
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• pp.371-377
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• 2015

Isotopic compositions of precipitation have been used to understand moisture transport in the atmosphere and interactions between precipitation and groundwater. Isotopic compositions of speleothems and ice cores, so called, ''paleoarchives'', can be utilized to interpret climate of the past and global circulation models (GCMs). The GCMs are able to explain the paleoarchives, can be validated by the precipitation isotopes. The developments of stable isotope analyzers make high-resolution isotopic studies feasible. Therefore, a high-resolution study of precipitation isotopes is needed. For this study, precipitation samples were collected for every 5 to 15 minutes, depending on precipitation rates, using an auto-sampler for precipitation isotopes near coastal area. The isotopic compositions of precipitation range from -5.7‰ (-40.1‰) to -10.8‰ (-74.3‰) for oxygen (hydrogen). The slope of ${\delta}^{18}O-{\delta}D$ diagram for the whole period is 6.8, but that of each storm is 5.1, 4.2, 7.9 and 7.7, respectively. It indicates that evaporation occurred during the first two storms, while the latter two storm did not experience any evaporation. The isotopic fractionations of precipitation has significant implications for the water cycle and high-resolution data of precipitation isotopes will be needed for the future studies.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.2
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• pp.65-69
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• 2014

Crystallographic phases of Plasma electrolytic oxidized Al alloy, A1100, A5052, A6061, A6063, A7075, were investigated. Two types of electrolyte $Na_2Si_2O_3$ and Na2P2O7 were also compared. Bipolar pulse, $2000{\mu}sec$ with $400{\mu}sec+420V$ impulse and $300{\mu}sec$ - impulse were applied for 20 min. ${\alpha}-alumina$, ${\gamma}-alumina$, ${\eta}-alumina$, $Al_{4.95}Si_{1.05}O_{9.52}$, and $(Al_{0.9}Cr_{0.1})_2O_3$ were mainly observed. Si, component of electrolyte, were moved into the PEO layer by bipolar pulse. Glassy phase was also observed at the surface of $Na_2Si_2O_3$ electrolyte treated PEO layer, and increased with the Mg content of Al alloy. It is concluded that at first glassy phase was formed by the micro plasma, and the high temperature of plasma turns glassy phase to several crystalline phases. And we could expect that many other crystalline phase could be formed by PEO process.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.2
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• pp.59-64
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• 2014

Crystallographic phases of Plasma electrolytic oxidized Al alloy, A1050, were investigated. The electrolyte of PEO was $Na_2Si_2O_3$ and KOH. Unipolar pulse, $ 2000{\mu}sec$ with $400{\mu}sec+420V$ impulse, were applied for 2 min, 5 min, 15 min, and 30 min. ${\gamma}-Alumina$, as well as ${\alpha}-alumina$, was main crystal phase. ${\gamma}-Alumina$ was appeared in the beginning, then the amount of ${\alpha}-alumina$ was increased with time, but the amount of ${\gamma}-Alumina$ remained constant without any increasing. So, it is concluded that plasma gas produce ${\gamma}-Alumina$ at the first, and then ${\gamma}-Alumina$ transform ${\alpha}-alumina$ finally. During the transformation, high temperature of micro plasma gives transformation energy.

• Journal of Hospice and Palliative Care
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• v.18 no.3
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• pp.227-234
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• 2015

Purpose: This study was done to analyze how a death preparation education program have the effects on awareness of hospice palliative care and withdrawing life sustaining treatment in older adults. Methods: This study employed a non-equivalent control group design among quasi-experimental designs. The experimental group was comprised with 35 adults and the control group with 40 adults. The death preparation program consisted of five two-hour sessions and was administered once a week for five straight weeks. Data were analyzed by descriptive statistics, t-test, ${\chi}^2$ test, Fisher's exact test, and ANCOVA using SPSS version 18.0. Results: The mean age of the participants was 66.2 years. A significant difference between the experimental and control groups was observed in withdrawing life sustaining treatment (F=3.380, P=0.040). However, no significant difference was found in awareness of hospice palliative care (F=0.163, P=0.850). Conclusion: The study results indicate that death preparation training could positively affect people's awareness of withdrawing life sustaining treatment. More studies should be conducted to explore effects of death preparation education for all ages and help people better understand hospice palliative care.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.3
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• pp.149-156
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• 2019

In the field of maintenance of power transmission lines, drones have been used for their patrol and inspection by KEPCO since 2017. This drone technology was originally developed by KEPCO Research Institute, and now workers from four regional offices of KEPCO have directly applied this technology to the drone patrol and inspection tasks. In the drone inspection system, a drone with an optical zooming camera and a thermal camera can fly automatically along the transmission lines by the ground control system developed by KEPCO Research Institute, but its camera gimbal has been remotely controlled by a field worker. Especially the drone patrol and inspection has been mainly applied for the transmission lines in the inaccessible areas such as regions with river-crossings, sea-crossings and mountains. There are often communication disruptions between the drone and its remote controller in such extreme fields of mountain areas with many barriers. This problem may cause the camera gimbal be out of control, even though the inspection drone flies along the flight path well. In addition, interference with the reception of real-time transmitted videos makes the field worker unable to operate it. To solve these problems, we have developed the auto-tracking camera gimbal system with deep learning method. The camera gimbal can track the transmission line automatically, even when the transmitted video on a remote controller is intermittently unavailable. To show the effectiveness of our camera gimbal system, its field test results will be presented in this paper.

• Journal of the Korea Convergence Society
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• v.12 no.9
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• pp.49-56
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• 2021

The purpose of this study was to provide a convergence suggestion of health care and social welfare services by empirically analyzing the effects of chronic diseases and quality of life on subjective health cognition in single-household women aged 60 or over. This study was based on the 2016-2019 Korea National Health and Nutrition Examination Survey, and 1,111 women who had been divorced or bereaved in single-household aged 60 or over were selected. As a result, it was arthritis that showed the largest average difference in subjective health cognition according to the prevalence of chronic diseases. And in the multiple regression analysis that was controlled for demographic characteristics, chronic disease had a negative (-) effect on subjective health cognition, and quality of life had a positive (+) effect on subjective health cognition. The negative (-) factor that had the greatest effect on subjective health cognition was diabetes(-0.084) among chronic diseases, and the positive (+) factor was mobility(+0.173) among the quality of life. Therefore, it suggests that health care services for chronic diseases should be strengthened in order to improve the subjective health cognition of single-person households over 60 years old, and social welfare policies to improve the quality of life should be considered together in a convergence.

• Journal of Breast Cancer
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• v.21 no.4
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• pp.453-462
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• 2018

Purpose: This study aimed to compare the diagnostic performance of contrast-enhanced digital mammography (CEDM) and contrast-enhanced magnetic resonance imaging (CEMRI) in preoperative evaluations, and to evaluate the effect of each modality on the surgical management of women with breast cancer. Methods: This single-center, prospective study was approved by the Institutional Review Board, and informed consent was obtained from all patients. From November 2016 to October 2017, 84 patients who were diagnosed with invasive carcinoma (69/84) and ductal carcinoma in situ (15/84), and underwent both CEDM and CEMRI, were enrolled. Imaging findings and surgical management were correlated with pathological results and compared. The diagnostic performance of both modalities in the detection of index and secondary cancers (multifocality and multicentricity), and occult cancer in the contralateral breast, was compared. The authors also evaluated whether CEDM or CEMRI resulted in changes in the surgical management of the affected breast due to imaging-detected findings. Results: Eighty-four women were included in the analysis. Compared with CEMRI, CEDM demonstrated a similar sensitivity (92.9% [78/84] vs. 95.2% [80/84]) in detecting index cancer (p=0.563). For the detection of secondary cancers in the ipsilateral breast and occult cancer in the contralateral breast, no significant differences were found between CEDM and CEMRI (p=0.999 and p=0.999, respectively). Regarding changes in surgical management, CEDM resulted in similar changes compared with CEMRI (30.9% [26/84] vs. 29.7% [25/84], p=0.610). Regarding changes in surgical management due to false-positive findings, no significant differences were found between CEDM and CEMRI (34.6% [9/26] vs. 44.0% [11/25], p=0.782). Conclusion: CEDM demonstrated a diagnostic performance comparable with CEMRI in depicting index cancers, secondary cancers, and occult cancer in the contralateral breast. CEDM demonstrated similar changes in surgical management compared with CEMRI.