• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권1호
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• pp.30-33
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• 2006

Transparent indium tin oxide (ITO) anode surface was modified using $O_3$ Plasma and organic ultrathin buffer layers were deposited on the ITO surface using 13.56 MHz RF plasma polymerization technique. The EL efficiency, operating voltage and lifetime of the organic light-emitting device (OLED) were investigated in order to study the effect of the plasma surface treatment and role of plasma polymerized organic ultrathin buffer layer. Poly methylmethacrylate (PMMA) layers were plasma polymerized on the ITO anode as buffer layer between anode and hole transport layer (HTL). The plasma polymerization of the organic ultrathin layer were carried out at a homemade capacitive-coupled RF plasma equipment. N,N'-diphenyl-N,N'(3- methylphenyl)-1,1'-diphenyl-4,4'-diamine (TPD) as HTL, Tris(8-hydroxyquinolinato) Aluminum $(Alq_3)$ as both emitting layer (EML)/electron transport layer (ETL), and aluminum layer as cathode were deposited using thermal evaporation technique. Effects of the plasma surface treatment of ITO and plasma polymerized buffer layers on the OLED performance were discussed.

• 한국전기전자재료학회논문지
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• 제13권11호
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• pp.943-949
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• 2000

In this paper, the single and double heterostructure organic light-emitting devices(OLEDs) were fabricated. The single heterostructure OLED(TYPE 1) is consisted of TPD as a HTL(hole transfer layer) and Alq$_3$as an EML(emitting layer). The double heterostructure OLED(TYPE 2) is consisted of TPD as a HTL, Alq$_3$as an EML and PBD as an ETL(electron transfer layer). The another double heterostructure OLED(TYPE 3) is consisted of TPD as a HTL, PBD as an EML and Alq$_3$as an ETL. We obtained a strong green emission device with maximum EL emission wavelength 500nm in TYPE 3. When the applied voltage was 12V, the emission luminescence was 120.9cd/㎡. The chromaticity index of TYPE 3 was x=0.29, y=0.50. In the characteristic plot of current-voltage, TYPE 3 device was turned on at 6.9V. This voltage was a fairly low turn-on voltage. TYPE 1 and 2 device were turned on at 10V and 8.9V respectively. These types showed no good properties over that of TYPE 3.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1412-1413
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• 2006

In this research, an organic thin 13 passivation layer was newly adopted to prefect the organic layer from ambient moisture and oxygen. As the organic thin film passivation layer, poly methyl methacrylate thin films (ppMMA) were deposited using a plasma polymerization technique. In order to their passivation performance for OLEDs, water vapor transmission rate (WVTR) of the ppMMAs were analyzed and luminance-current-voltage (L-I-V)/luminance-time (L-T) characteristics of the OLEDs with and without ppMMA passivation layer were investigated. The OLEDs had a structure of ITO/TPD (HTL)/Alq3(EML&ETL)/Al. The OLED with ppMMA passivation layer showed improved L-T performance than that of without ppMMA passivation layer.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권6호
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• pp.3280-3298
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• 2019

Vehicular ad-hoc networks (VANETs) have become increasingly significant in intelligent transportation systems, they play a great role in improving traffic safety and efficiency. In the deployment of intelligent VANETs, intelligent vehicles can efficiently exchange important or urgent traffic information and make driving decisions. Meanwhile, secure data communication and vehicle's identity privacy have been highlighted. To cope with these security issues, in this paper, we construct an efficient anonymous authentication scheme with secure communication in intelligent VANETs. Combing the ElGamal encryption technique with a modified Schnorr signature technique, the proposed scheme provides secure anonymous authentication process for encrypted message in the vehicle-to-infrastructure communication model, and achieves identity privacy, forward security, and reply attack resistance simultaneously. Moreover, except the trusted authority (TA), any outside entity cannot trace the real identity of an intelligent vehicle. The proposed scheme is designed on an identity-based system, which can remove the costs of establishing public key infrastructure (PKI) and certificates management. Compared with existing authentication schemes, the proposed scheme is much more practical in intelligent VANETs.

• Annals of Rehabilitation Medicine
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• 제42권6호
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• pp.854-862
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• 2018

Objective To investigate the effect of treadmill training with eyes open (TEO) and closed (TEC) on the knee joint position sense (JPS), functional balance and mobility in children with spastic diplegia. Methods Forty-five children with spastic diplegia aged 11-13 years participated in this study. They were randomly assigned to three groups of equal number. The control group (CON) underwent designed physical therapy program whereas, the study groups (TEO and TEC) underwent the same program, in addition to treadmill gait training with eyes open and closed, respectively. Outcome measures were the degree of knee joint position error, functional balance and mobility. Measurements were taken before and after 12 weeks of intervention. Results After training, the three groups showed statistically significant improvement in all measured outcomes, compared to the baseline with non-significant change in the knee JPS in the CON group. When comparing posttreatment results, the TEC group showed greater significant improvement in all measured outcomes, than the TEO and CON groups. Conclusion Treadmill training with eyes open and closed is effective in rehabilitation of children with diplegia, but blocked vision treadmill training has more beneficial effect.

• The Journal of Asian Finance, Economics and Business
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• 제8권3호
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• pp.539-549
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• 2021

This study aims to examine the relationship between corporate social responsibility (CSR) expenditures and both financial and non-financial performance of Jordanian commercial banks during the period 2008-2018. To measure the variables of interest, secondary data published on Amman Stock Exchange (ASE) website were processed to become preliminary data suitable for the nature of the study. The study sample amounted to 13 commercial banks, which represent all Jordanian commercial banks listed on ASE.. The study found that there is a positive, statistically significant relationship between CSR expenditures and financial performance, as the study showed that the return on equity (ROE) has a positive and significant relationship with CSR expenditure, while the return on assets (ROA) and Tobin's Q model have a statistically significant negative relationship with CSR expenditure, while the market stock price (MSP) had a positive, but not statistically significant. The study also found that there is a positive, statistically significant relationship between CSR expenditures and non-financial performance, which was represented by total deposits and total training expenditures in Jordanian commercial banks. Accordingly, the study recommends encouraging banks to prepare sustainability reports and CSR reports, which are considered comprehensive, and not only with disclosures within the annual reports.

• Structural Engineering and Mechanics
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• 제77권5호
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• pp.673-689
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• 2021

This paper addresses the efficiency of thermal insulation layers applied to protect structural elements strengthened by fiber-reinforced polymers (FRP) in the case of fire event. The paper presents numerical modeling and nonlinear analysis of reinforced concrete (RC) columns externally strengthened by FRP and protected by thermal insulation layers when subjected to elevated temperature specified by standard fire tests, in order to predict their residual capacity and fire endurance. The adopted numerical approach uses commercial software includes heat transfer, variation of thermal and mechanical properties of concrete, steel reinforcement, FRP and insulation material with elevated temperature. The numerical results show good agreement with published results of full-scale fire tests. A parametric study was conducted to investigate the influence of several variables on the structural response and residual capacity of insulated FRP-confined columns loaded by service loads when exposed to fire. The residual capacity of FRP-confined RC column was affected by concrete grade and insulation material and was shown to improve substantially by increasing the concrete cover and insulation layer thickness. By increasing the VG insulation layer thickness 15, 32, 44, 57 mm, the loss in column capacity after 5 hours of fire was 30%, 13%, 7% and 5%, respectively. The obtained results demonstrate the validity of the presented approach for estimation of fire endurance and residual strength, as an alternative for fire testing, and for design of fire protection layers for FRP-confined RC columns.

• Journal of Ceramic Processing Research
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• 제13권spc2호
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• pp.295-299
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• 2012

We investigated the crystal and the optical properties of GaN-based blue light emitting diodes (LEDs) which were simultaneously grown on c-plane (0001) and semipolar (11-22) GaN templates by using metal-organic chemical vapor deposition (MOCVD). The X-ray rocking curves (XRCs) full width at half maximums (FWHMs) of c-plane (0001) and semipolar (11-22) GaN templates were 275 and 889 arcsec, respectively. In addition, high-resolution X-ray ω-2θ scan showed that satellite peaks of semipolar (11-22) InGaN quantum-wells (QWs) was weaker and broader than that of c-plane (0001) InGaN QWs, indicating that the interface quality of c-plane (0001) QWs was superior to that of semipolar (11-22) QWs. Photoluminescence (PL) and electroluminescence (EL) results showed that the emission intensity and the FWHMs of polar c-plane (0001) LED were much higher and narrower than those of semipolar (11-22) LED, respectively. From these results, we believed that relative poor crystal quality of semipolar (11-22) GaN template might give rise to the poor interfacial quality of QWs, resulting in lower output power than conventional c-plane (0001) GaN-based LEDs.

• Clinical Endoscopy
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• 제56권1호
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• pp.92-99
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• 2023

Background/Aims: There are few studies assessed the efficacy and mortality of endoscopic retrograde cholangiopancreatography (ERCP) for the removal of common bile duct (CBD) stones in the elderly aged ≥90 years. We aimed to assess the safety and efficacy of endoscopic removal of CBD stones in nonagenarians. Methods: We retrospectively reviewed ERCP reports for CBD stone removal. The endoscopic and therapeutic outcomes were collected. The length of stay (LOS), the total number of adverse events, and mortality rate were compared between groups. Results: A total of 125 nonagenarians were compared with 1,370 controls (65-89 years old individuals). The mean LOS for nonagenarians was significantly higher than in controls (13.6 days vs. 6.5 days). Completed intended treatment was similar in the nonagenarians and controls (89.8% and 89.5%, respectively). The overall complication rate did not differ between the groups. However, nonagenarians had a higher incidence of post-ERCP pneumonia (3.9%). None of the nonagenarians were readmitted to the hospital within 7 days. Four nonagenarians (3.2%) and 25 (1.8%) controls died within 30 days. Conclusions: Advanced age alone did not affect the decision to perform the procedure. However, prompt diagnosis and treatment of post-ERCP pneumonia in nonagenarians could improve the outcomes and reduce mortality.

• Asian Pacific Journal of Cancer Prevention
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• 제13권2호
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• pp.705-714
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• 2012

Objectives: This study assessed the associations between socio-demographic, health and wellbeing variables (independent variables) and daily smoking, attempts to quit smoking, and agreement with smoking ban (dependent variables). Methods: Data from 3,706 undergraduate students were collected from seven universities in England, Wales, and Northern Ireland using a standardised questionnaire. Results: About 15.8% of the whole sample reported daily smoking, while 12% were occasional smokers. Smoking was significantly more prevalent among males, but the difference was due to a higher rate of occasional smokers. About every second smoker (55%) had attempted to quit smoking. Almost 45% of the whole sample agreed or strongly agreed with implementing a total smoking ban on campus. Daily smoking was more likely among students with not sufficient income, students whose fathers had at least a bachelor degree; and, students who reported binge drinking. Conversely, daily smoking was less likely among students who rated their health as very good/ excellent, those who ate ${\geq}5$ portions of fruit or vegetables, and those who had never taken illicit drugs. Previous attempt/s to quit smoking were more likely among students who have never taken illicit drugs and those who agreed with a total smoking ban; and less likely among those with not sufficient income. Daily smokers were less likely to report quit attempts as compared to occasional smokers. An agreement with smoking ban was more likely among students who rated their health as very good/excellent, those who ate ${\geq}5$ portions of fruit or vegetables daily, and those who had never taken illicit drugs, but less likely among daily smokers. Conclusion: Favourable health practices and positive attitudes towards smoking ban were associated with each other. Interventions would need to comprise multi-component programmes that do not solely focus on smoking prevention/cessation, but also on other health promoting practices as well.