Publications by authors named "Young Bae Park"

In this study, we investigated the brittle fracture behavior of Sn-3.0Ag-0.5Cu (SAC305) solder joints with a Direct Electroless Gold (DEG) surface finish, formed using laser-assisted bonding (LAB) and mass reflow (MR) techniques.

View Article and Find Full Text PDF

This study suggests a Ru/ZnO bilayer grown using area-selective atomic layer deposition (AS-ALD) as a multifunctional layer for advanced Cu metallization. As a diffusion barrier and glue layer, ZnO is selectively grown on SiO , excluding Cu, where Ru, as a liner and seed layer, is grown on both surfaces. Dodecanethiol (DDT) is used as an inhibitor for the AS-ALD of ZnO using diethylzinc and H O at 120 °C.

View Article and Find Full Text PDF

Background: Although vasospastic angina (VSA) is known to be caused by coronary artery spasm, no study has fully elucidated the exact underlying mechanism. Moreover, in order to confirm VSA, patients should undergo invasive coronary angiography with spasm provocation test. Herein, we investigated the pathophysiology of VSA using peripheral blood-derived induced pluripotent stem cells (iPSCs) and developed an ex vivo diagnostic method for VSA.

View Article and Find Full Text PDF

Controlling the contact properties of a copper (Cu) electrode is an important process for improving the performance of an amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistor (TFT) for high-speed applications, owing to the low resistance-capacitance product constant of Cu. One of the many challenges in Cu application to a-IGZO is inhibiting high diffusivity, which causes degradation in the performance of a-IGZO TFT by forming electron trap states. A self-assembled monolayer (SAM) can perfectly act as a Cu diffusion barrier (DB) and passivation layer that prevents moisture and oxygen, which can deteriorate the TFT on-off performance.

View Article and Find Full Text PDF

Obesity is known as metabolic syndrome and it affects many tissues including adipose tissue, liver, and central nervous system (CVS). Gambi-jung (GBJ) is a modified prescription of Taeumjowi-tang (TJT), which has been used to treat obesity in Korea. GBJ is composed of 90% Ephedra sinica Stapf (ES).

View Article and Find Full Text PDF

Background: Portion control is a useful component of weight reduction interventions and meal replacement (MR) plans represent a promising strategy for portion control. Research performed with pooled data on the effect of MR plans according to various characteristics of MR interventions remains scarce.

Objective: Our aim was to assess the effects of MR-based diets compared with food-based diets on weight loss, according to calorie-restriction types and energy intake proportions from MR.

View Article and Find Full Text PDF

Many studies have shown the existence of cardiac stem cells in the myocardium and epicardial progenitor cells in the epicardium. However, the characteristics of stem cells in the endocardium has not been fully elucidated. In this study, we investigated the origin of newly identified cells in the blood and their therapeutic potential.

View Article and Find Full Text PDF

To develop highly reliable flexible electronics, mechanical reliability during mechanical deformation such as repeated bending is an important issue. Bending test methodologies to estimate long-term reliability during repeated mechanical deformation are attracting substantial interest from related researchers and industry insiders. In this study, four representative bending test methodologies for testing flexible electronics are introduced: free arc bending test, variable radius bending test, sliding plate test, and variable angle test.

View Article and Find Full Text PDF

The effects of annealing, electromigration, and thermomigration on volume shrinkage and voiding mechanisms of Cu/Ni/Sn-2.5Ag microbumps are systematically investigated by using scanning electron microscopy under current stressing of 1.5×10 A/cm² at 150 °C.

View Article and Find Full Text PDF

The effects of environmental conditions on the interfacial adhesion between screen-printed Ag film and polyimide substrate interface are quantitatively evaluated using the 90° peel test. The adhesion of printed patterns is varied by annealing time and atmosphere conditions. The peel strengths of air, high vacuum, and N₂ atmosphere samples increase after post-annealing for 24 h, which are closely related to the curing effect of binder in Ag paste.

View Article and Find Full Text PDF

Symptomatic hyperventilation (SH) is a pathological condition that manifests with breathlessness, dyspnea, light-headedness, anxiety, and paresthesia. However, little is known about the prevalence of SH and its association with health-related quality of life (HRQoL) in a young population. The Nijmegen questionnaire (NQ), which measures severity of SH, had not previously been cross-culturally translated into Korean.

View Article and Find Full Text PDF

Tongue diagnosis is a technique used to determine cold-heat pathologic patterns (CHPPs). Herein, we reviewed electronic medical records of tongue temperature measured using infrared thermography (IRT), tongue color (luminance, green/red, and blue/yellow balance), cold-heat pattern questionnaires (CHPQ), and body temperature for 134 women with gynecological problems (age, 38.97 ± 11.

View Article and Find Full Text PDF

Objective: To culturally translate the cardiff acne disability index (CADI) into Korean, and to examine its relationship with clinical acne severity, pathological patterns, and general quality of life (QoL).

Methods: The CADI was culturally and lin- guistically translated into Korean via translation, back-translation, and face validity test process. Two hundred and fifty-four Korean adolescents were asked to complete the Korean version of the CADI (K-CADI), the Phlegm Pattern, the Cold-Heat Pattern, and the Korean version of the General Health Questionnaires.

View Article and Find Full Text PDF

Objective: To develop and validate a Seven Emotions Impairment questionnaire (SEIQ), to define an optimum cut-off point for the SEIQ, and to examine whether SEI was predictive of Phlegm and Blood Stasis (BS).

Methods: Two hundred outpatients and 75 college students were asked to complete the SEIQ, the Profile of Mood States (POMS), Phlegm Pattern Questionnaire (PPQ), and BS Questionnaire (BSQ). Twelve clinicians determined whether the outpatients exhibited SEI.

View Article and Find Full Text PDF

comprises varied senses depending on the individual. No single method can yet fully measure the multiple dimensions of adequately. We examined the advantages of implementing multiple questionnaires for measurement.

View Article and Find Full Text PDF

Background: Acupuncture treatments that regulate the heart are used to treat various clinical disorders and conditions. Although many studies have been conducted to measure quantitatively the effects of acupuncture, thus far, models that describe these effects have not been established. The purpose of this study was to derive a transfer function model of acupuncture stimulation within the electrocardiograms based on the periods before, during, and after acupuncture.

View Article and Find Full Text PDF

. In Korea, a few studies regarding traditional Korean medicine (TKM) education have been conducted. The aim of this study is to evaluate students' perceptions regarding TKM education in Korea and compare them with those of other countries using a quantitative scale, Dundee Ready Educational Environment Measure (DREEM).

View Article and Find Full Text PDF

In spite of its great success in reducing restenosis, drug-eluting stent (DES) has unfavorable aspects such as stent thrombosis and delayed re-endothelialization. We examined the effects of PKG activation by Exisulind on neointimal formation, platelet aggregation, and re-endothelialization. Exisulind significantly reduced VSMCs viability, cell cycle progression, migration, and neointimal hyperplasia after vascular injury in rat carotid arteries.

View Article and Find Full Text PDF

Background: Several mechanisms have been proposed to account for diabetes-induced microvasculopathy (DMV). Although Notch signaling was reported to be affected by glucose metabolism in endothelial cells during developmental angiogenesis, it has not been investigated in vascular remodeling of adult capillaries in relation to diabetes mellitus.

Methods: We induced diabetes mellitus in 8-week-old adult mice by intravenously administering streptozotocin.

View Article and Find Full Text PDF

Objective: To examine whether color parameters of tongue inspection (TI) using a digital camera was reliable and valid, and to examine which color parameters serve as predictors of symptom patterns in terms of East Asian medicine (EAM).

Methods: Two hundred female subjects' tongue substances were photographed by a mega-pixel digital camera. Together with the photographs, the subjects were asked to complete Yin deficiency, Phlegm pattern, and Cold-Heat pattern questionnaires.

View Article and Find Full Text PDF

Background: Peroxisome proliferator-activated receptor (PPAR)-δ is a nuclear receptor regulating cell metabolism. The role of PPAR-δ in late endothelial progenitor cells (EPCs) has not been fully elucidated. We aim to understand the effects of PPAR-δ activation on late EPC and to reveal the underlying mechanism.

View Article and Find Full Text PDF

Background. Phlegm pattern questionnaire (PPQ) was developed to evaluate and diagnose phlegm pattern in Korean Medicine and Traditional Chinese Medicine, but it was based on a dataset from patients who visited the hospital to consult with a clinician regarding their health without any strict exclusion or inclusion. In this study, we reinvestigated the construct validity of PPQ with a new dataset and confirmed the feasibility of applying it to a healthy population.

View Article and Find Full Text PDF

In this work, intermetallic compound (IMC) growth behavior in Au stud/Sn/Cu pillar bumps was investigated under annealing and current stressing conditions. AuSn2 and AuSn4 IMCs formed at the interface between the Au studs and Sn after bonding. The AuSn2 phase grew significantly as the stressing time increased, causing micro-voids to form near the (Cu, Au)6Sn5, AuSn2 and AuSn4 IMC interfaces.

View Article and Find Full Text PDF

The effects of annealing, thermomigration (TM), and electromigration (EM) on the intermetallic com- pound (IMC) growth kinetics of Cu/Sn-2.5Ag microbumps were investigated using in-situ scanning electron microscopy at 120-165 degrees C with a current density of 1.5 x 10(5) A/cm2.

View Article and Find Full Text PDF

Background: The aim of this study was to investigate the physical properties and biological effects of an experimentally developed injectable premixed calcium-silicate root canal sealer (Endoseal) in comparison with mineral trioxide aggregate (MTA) and a resin-based sealer (AHplus).

Methods: The pH, solubility, dimensional change, flow, and radiopacity of the materials were evaluated. Biocompatibility was evaluated on the basis of cell morphology and a viability test using MC3T3-E1 cells.

View Article and Find Full Text PDF