• Title/Summary/Keyword: Cross-linked structure

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Development and Psychometric Evaluation of the Resuscitation Self-efficacy Scale for Nurses

  • Roh, Young Sook;Issenberg, S. Barry;Chung, Hyun Soo;Kim, So Sun
    • Journal of Korean Academy of Nursing
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    • v.42 no.7
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    • pp.1079-1086
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    • 2012
  • Purpose: The purpose of this study was to develop and evaluate psychometric properties of the instrument, Resuscitation Self-Efficacy Scale for nurses. Methods: This was a methodological study for instrument development and psychometric testing. The initial item pool derived from literature review and experts resulted in 30 items linked to resuscitation self-efficacy. A convenience sample of 509 Korean nurses from eleven academic teaching hospitals participated in a survey to examine psychometric properties of the scale. To examine construct validity, exploratory factor analysis and known-group comparison were used. Cronbach's coefficient alpha was used to determine the scale's internal consistency reliability. Results: The final scale included 17 items with four-component structure termed 'Recognition', 'Debriefing and recording', 'Responding and rescuing', and 'Reporting'. These four factors accounted for 57.5% of the variance. Each subscale and the total scale demonstrated satisfactory internal consistency: .82; .88; .87; .83; and .91 respectively. Experienced nurses reported significantly higher self-efficacy mean scores in both total and subscales compared to new graduate nurses. Conclusion: The Resuscitation Self-Efficacy Scale for nurses yields reliable and valid results in appraising the level of resuscitation self-efficacy for Korean nurses. Further study is needed to test and refine the scale.

Fabrication of SiCN microstructures for super-high temperature MEMS using PDMS mold and its characteristics (PDMS 몰드를 이용한 초고온 MEMS용 SiCN 미세구조물 제작과 그 특성)

  • Chung, Gwiy-Sang;Woo, Hyung-Soon
    • Journal of Sensor Science and Technology
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    • v.15 no.1
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    • pp.53-57
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    • 2006
  • This paper describes a novel processing technique for fabrication of polymer-derived SiCN (silicone carbonitride) microstructures for super-temperature MEMS applications. PDMS (polydimethylsiloxane) mold is fabricated on SU-8 photoresist using standard UV photolithographic process. Liquid precursor is injected into the PDMS mold. Finally, solid polymer structure is cross-linked using HIP (hot isostatic pressure) at $400^{\circ}C$, 205 bar. Optimum pyrolysis and annealing conditions are determined to form a ceramic microstructure capable of withstanding over $1400^{\circ}C$. The fabricated SiCN ceramic microstructure has excellent characteristics, such as shear strength (15.2 N), insulation resistance ($2.163{\times}10^{14}{\Omega}$) and BDV (min. 1.2 kV) under optimum process condition. These fabricated SiCN ceramic microstructures have greater electric and physical characteristics than bulk Si wafer. The fabricated SiCN microstructures would be applied for supertemperature MEMS applications such as heat exchanger and combustion chamber.

Electrical Characteristic Analysis of IGZO TFT with Poly (4-vinylphenol) Gate Insulator according to Annealing Temperature (Poly (4-vinylphenol) 게이트 절연체를 적용한 IGZO TFT의 열처리 온도에 따른 전기적 특성 분석)

  • Park, Jung Hyun;Jeong, Jun Kyo;Kim, Yu Jeong;Jun, Jung Byung;Lee, Ga Won
    • Journal of the Semiconductor & Display Technology
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    • v.16 no.1
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    • pp.97-101
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    • 2017
  • In this paper, IGZO thin film transistor (TFT) was fabricated with cross-linked Poly (4-vinylphenol) (PVP) gate dielectric for flexible, transparent display applications. The PVP is one of the candidates for low-temperature gate insulators. MIM structure was fabricated to measure the leakage current and evaluate the insulator properties according to the annealing temperature. Low leakage current ( <0.1nA/cm2 @ 1MV/cm ) was observed at $200^{\circ}C$ annealing condition and decreases much more as the annealing temperature increases. The electrical characteristics of IGZO TFT such as subthreshold swing, mobility and ON/OFF current ratio were also improved, which shows that the performance of IGZO TFTs with PVP can be enhanced by reducing the amount of incomplete crosslinking in PVP.

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Sensor Mat using POF for Medical Application (의료용 플라스틱 광섬유 센서 매트)

  • Choi, Kyoo-Nam
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.44 no.4 s.316
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    • pp.74-78
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    • 2007
  • Novel concept of sensor mat and its signal processing method is proposed for patient monitoring in medical application. Proposed sensor mat structure has sensing inner layer which has cross-linked arrangement using plastic optical fiber(POF). Large core diameter of plastic optical fiber behaved as band pass filter by averaging the noise component caused by unwanted environmental factors. Signal processor followed by sensor output added noise immune performance by filtering out unwanted component. Fail-proof patient breath monitoring scheme was realized by using intelligent decision algorithm. Unlike the conventional approach by using mechanical sensor, which have high sensitivity both to signal and to environmental noise, our approach provided reliable breath motion detection.

Recycling Technology of Crosslinked-Polymers Using Supercritical Fluid (초임계 유체를 이용한 가교고분자 재활용기술)

  • Koo, Chong-Min;Yu, Si-Won;Baek, Bum-Ki;Cho, Hang-Kyu;Lee, Youn-Woo;Hong, Soon-Man
    • Elastomers and Composites
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    • v.47 no.2
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    • pp.111-120
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    • 2012
  • Industrial wastes of crosslinked polymers have been burned or disposed of in landfills because there is no recycling technology due to their insoluble and infusible network chain structure. However, recycling of cross-linked polymers has been taken a growing attention because of issues of environmental pollution and of resources conservation. In this paper, uprising recycling technologies of crosslinked polymers using supercritical fluid are reviewed.

Effect of Combined Superabsorbent Polymers and Expansion Agent on Shrinkage Behavior of High Strength Mortar (고흡수성수지와 팽창재 동시 혼입 시 고강도 모르타르의 수축거동에 미치는 영향)

  • Kim, Minsoo;Hong, Sung-Gul
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.35 no.12
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    • pp.157-164
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    • 2019
  • Superabsorbent polymers(SAPs) are powdery material that absorb water several tens or hundreds of times its own mass. It has been reported that when SAPs are incorporated into a high strength cementitious material, the autogenous shrinkage of the material is reduced. Cross-linked sodium polyacrylate type SAPs are relatively safe for human body and low in production cost. In order to apply this type of SAPs to the admixture for total(plastic+autogenous+drying) shrinkage reduction of high strength mortar, the shrinkage behavior of mortar when an expansion agent(EA) and SAPs were mixed together was analyzed. As a result, it was found that the shrinkage was reduced when an EA 5% (mass % of cement) and SAPs 0.4% were mixed together than the mortar containing only an EA 10%. The shrinkage was further reduced when EA 10% and SAPs 0.4% were incorporated into mortar.

Multimedia Document Databases : Representation, Query Processing and Navigation

  • Kalakota, Ravi S.;Whinston, Andrew B.
    • The Journal of Information Technology and Database
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    • v.1 no.1
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    • pp.31-62
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    • 1994
  • Information systems for application areas like office automation, customer service or computer aided manufacturing are usually highly interactive and deal with complex document structures composed of multiple media formats. For the realization of these systems, nonstandard database systems, which we call document databases, need to handle different types of coarse-and fine-grained document objects(like full-text documents, graphics and images), hierarchical and non-hierarchical relationships between objects(like composition-links and cross-references using hypertext structures) and document attributes of different types such as formatting/presentation information and access control. In this paper, we present the underlying data model for document databases based on descriptive markup languages that provide mechanisms for specifying the logical structure(or schema) of individual documents stored in the database. We then describe extensions to the data model for supporting notion of composite structures("join" operators for documents) --composition and hyperlinking mechanisms for representing compound documents and inter-linked documents as unique entites separate from their components. Furthermore, due to the interactive nature of the application domains, the database system in conjunction with clients(or browsers) has to support visual navigation and graphical query mechanisms. We describe the functionality of a new user interface paradigm called HyBrow for meeting the above mentioned requirements. The underlying implementation strategy is also discussed.discussed.

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Digital Predistortion for Multi-band/Multi-mode Transmission Systems (다중 대역 전송 시스템을 위한 전치왜곡 알고리즘)

  • Choi, Sung-Ho;Lee, Byung-Hwan;Lee, Chul-Soo;Jeong, Eui-Rim
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.1
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    • pp.48-58
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    • 2012
  • New digital predistortion technique is proposed for power amplifier linearization in multi-band transmission systems. We consider a system where muli-band signals are combined and amplified by a single power amplifier (PA). In this system, the PA output is distorted by the nonlinear cross-products between different band signals as well as their own nonlinear self-products. To compensate these nonlinear effects, we propose a multiple PD structure. Each PD removes the nonlinear cross-products and self-products to mitigate the spectral regrowth for the corresponding band. Since the PD parameters for different bands are linked together, it is difficult to find the PD parameters separately. Thus, we propose an iterative method for finding the PD parameters jointly. For demonstration of the proposed method, multi-band characteristics of PA are extracted from a commercial power amplifier. Computer simulation was executed based on the PA parameters. The simulation results show that the proposed method can effectively linearize the PA and remove spectral regrowth at each signal band.

Immobilization of Glucose Oxidase using Branched Polyethyleneimines of Various Molecular Weights for Glucose Based Biofuel Cell (글루코스 기반 바이오연료전지를 위한 다양한 분자량의 폴리에틸렌이민을 이용한 글루코스 산화효소 고정화)

  • Ahn, Yeonjoo;Chung, Yongjin;Kwon, Yongchai
    • Korean Chemical Engineering Research
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    • v.54 no.5
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    • pp.693-697
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    • 2016
  • In this study, we fabricated the catalysts for enzymatic biofuel cell anode with carbon nanotube (CNT), glucose oxidase (GOx) and various molecular weights branched poly(ethyleneimine)(bPEI) and terephthalaldehyde (TPA) as cross-linker. In case of GOx/bPEI/CNT using only physical entrapments for immobilization, the molecular weights of bPEI didn't affect to electrochemical performances and long term stability. but that of the catalysts cross linked via TPA (TPA[GOx/bPEI/CNT]) improved and the mass transfer of glucose to FAD was interrupted as increasing of the bPEI's molecular weights. Furthermore, it was confirmed that the optimum molecular weight of PEI for TPA [GOx/bPEI/CNT]) structure is 750k that showed marvelous high performance (maximum power density of $0.995mW{\cdot}cm^{-2}$).

Protein unfolding by ATP-dependent proteases

  • Lee, Cheolju;Michael Schwartz;Sumit Prakash;Masahiro Iwakura;Andreas Matouschek
    • Proceedings of the Korean Biophysical Society Conference
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    • 2003.06a
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    • pp.34-34
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    • 2003
  • Protein unfolding is a key step in several cellular processes, including protein translocation across some membranes and protein degradation by ATP-dependent proteases. C1pAP protease and the proteasome can actively unfold proteins in a process that hydrolyzes ATP, These proteases catalyze unfolding by processively unraveling their substrates from the attachment point of the degradation signal. As a consequence, the ability of a protein to be degraded depends on its structure as well as its stability. An ${\alpha}$-helix is easier to unravel than a ${\beta}$-strand. In multidomain proteins, independently stable domains are unfolded sequentially. The steric constraints imposed on substrate proteins during their degradation by the proteasome were investigated by constructing a model protein in which specific parts of the polypeptide chain were covalently connected through disulfide bridges. The cross-linked model proteins were fully degraded by the proteasome, but two or more cross-links retarded the degradation slightly. Our results suggest that the pore of the proteasome allows the concurrent passage of at least three stretches of a polypeptide chain, and also explain the limited degradation by the proteasome that occurs in the processing of the transcription factor NF-KB, and also implicate difficulty in degradation of amyloidal aggregates by the proteasome

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