Mechanical behavior and in vivo properties of newly designed bare metal stent for enhanced flexibility

배인호,임경섭,박준규,박대성,이소연,장은재,지미선,심두선,홍영준,안영근,박종춘,조정관,강정채,김인수,나재운,정명호 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

In this study, our own stent designed by Chonnam National University Hospital (designated as CNUHstent) which is considered an elastic behavior as second trial was subjected to mechanical performancetests and in vivo histological analysis. Four commercialized stents (PROMUS ElementTM, Cypher1,Resolute Integrity, Xience PRIME) stents were employed as control. In the flat plate and compression testfor measuring radial force, the lowest (2.40 0.27 N) and moderate (31.27 4.84 N) performance wasshown in CNUH stent compared to others. On the other hand, In the 3-point bending test for measuringflexibility, CNUH stent showed the greatest flexibility (0.46 0.08 N) among competitors (range between0.66 0.03 in Cypher1 and 1.14 0.04 Resolute Integrity), In both foreshortening and recoil test, CNUHstent showed reasonable result (2.13 0.15% and 3.29 0.41%, respectively). However, histological analysisshowed that CNUH stent has any significant difference to Coroflex1 Blue BMS on various parameters. Although the radial force of CNUH stent was slightly lower than that of other products, it showed the greatestperformance in its flexibility. It can be utilized for developing drug-eluting stent as a basic structure.

Spatial Information Transfer with a Stationary Coupling Wave in Rb Atoms

배인호,문한섭 한국광학회 2008 Current Optics and Photonics Vol.12 No.3

We report on the spatial information of a coupling laser transfer into a reflected probe laser; the transfer is achieved by means of electromagnetically induced transparency through a common excited state connected with 5S1/2-5P1/2 (F=1→F’=2) in the 87Rb D1 line. When the coupling laser was spatially modulated as a stationary wave, the absorption of the probe laser was enhanced and the reflection of the probe laser was generated. When the coupling laser was spatially modulated by a mask, we observed that the reflection light of the probe laser was modulated as the shape of the mask. The Bragg reflection transferred the spatial information of the coupling laser. The reflection was approximately 7% of the incident power of the probe laser.

Mid-infrared Continuous-wave Optical Parametric Oscillator with a Fan-out Grating MgO:PPLN Operating Up to 5.3 µm

배인호,유재근,임선도,김승관,이동훈 한국광학회 2019 Current Optics and Photonics Vol.3 No.6

We report on a continuous-wave (cw) optical parametric oscillator (OPO) optimized for mid-infrared emission above 5.0 µm. The OPO is based on a magnesium-oxide-doped periodically poled LiNbO 3(MgO:PPLN) crystal with a fan-out grating design. A linear two-mirror cavity resonating both at the pump and signal wavelengths is stabilized to the pump laser by using the modified Pound-Drever-Hall (PDH) method. The idler wavelength is continuously tunable from 4.7 µm up to 5.3 µm by varying the poling period of the fan-out grating crystal. Pumped by a diode-pumped solid state (DPSS) laser with a power of 1.1 W at 1064 nm, the maximum idler output power is measured to be 5.3 mW at 4.8 µm. The output power above 5.0 µm is reduced to the hundreds of µW level due to increased absorption in the crystal, but is stable and strong enough to be measured with a conventional detector.

치차성능의 최적성과 강건성을 고려한 치차제원 및 치면수정의 설계

배인호,정태형 한국공작기계학회 2004 한국생산제조학회지 Vol.13 No.4

Tooth errors inevitable in the manufacturing process have large effect on the strength/durability and vibration performances of gear drives. We show that the manufacturing errors affect the overall gear performances, especially vibration performance, and propose a robust optimal design method for gear dimension and its tooth flank form that guarantees reliable performances to the variation of manufacturing errors. This method begins with a search of optimal design candidates by using the previously developed gear optimal design method for the strength/durability and vibration performances. Then, the statistical analysis method is applied to find a robust design solution for the vibration performance which is generally very sensitive to the manufacturing variations.

Morphological Property and In vitro Enzymatic Degradation of Modified Chitosan as a Scaffold

배인호,고정태,장원구,임현필,박상원,이광민,박영준,박인규,정명호 한국고분자학회 2011 Macromolecular Research Vol.19 No.12

Chitosan (CS) was proposed as a promising candidate scaffold for tissue engineering. However, some drawbacks of natural CS remain. The current study modified CS by conjugating thiol to CS polymer (Thio-CS) and substantiated its three-dimensional microstructure and physical properties such as swelling or degradation. The Thio-CS was obtained by CS modification using 2-iminothiolane-HCl (2-IT). Because of the formation of disulfide bonds between thiol moieties based on oxidation of the immobilized thiol groups of CS, Thio-CS exhibits in situ gelling properties according to the reducing amount of free thiol. The content of the thiol group was increased as the amount of 2-IT increased. The swelling test demonstrated that Thio-CS can absorb up to 3.5 times its weight of phosphate buffered saline within 1 h and that the pore size and amount significantly increased with incubation time. The Thio-CS enzymatic degradation rate according to velocity was investigated. The results showed that Thio-CS was more resistant to lysozyme as viscosity increased. Thio-CS sponges were fabricated using freezedrying. The lyophilized Thio-CS had a homogeneous honeycomb-like shape, and its pores were relatively smaller (<2 μm) than those of unmodified CS (>2 μm). These results suggest that Thio-CS might be a candidate regenerative therapeutic device.

In1-xGaxP/GaAs 이종접합 구조의 Photoreflectance 특성

배인호,김기홍,박성배,김인수,조광호 한국물리학회 2003 새물리 Vol.46 No.2

In$_{1-x}$Ga$_x$P/GaAs epilayers grown by using metalorganic chmical vapor deposition were investigated using photoreflectance (PR) measurements. We observed the bandgap transitions of the In$_{1-x}$Ga$_x$P/GaAs heterojunction. The band gap ($E_0$), the broadening parameter ($\Gamma$), and the internal electric field ($E_i$) were obtained from the observed Franz-Keldysh oscillation by using Aspnes' equation. The Ga composition ($x$=0.51) was determined from Robert's composition formula and by measuring the frequency dependence of the In$_{1-x}$Ga$_x$P/GaAs heterojunction, we were able to observe that the PR line shape did not change, but the amplitude did. This results was due to the difference between the lifetimes of the photocarriers in GaAs and in In$_{1-x}$Ga$_x$P. Good agreement between the experimental and the calculated values of the bandgap transition energies were found in the temperature range from 77 K to 300 K. Metalorganic chemical vapor deposition(MOCVD)법으로 성장한 In$_{1-x}$Ga$_x$P/GaAs 이종접합 구조의 특성을 비접촉, 비파괴법인 photoreflectance(PR) 방법으로 연구하였다. 실온에서, In$_{1-x}$Ga$_x$P/GaAs 이종접합 구조의 띠사이 흡수 전이에 대한 피크를 관측하여, PR 측정값을 3차미분형태로 피팅한 띠 간격 에너지($E_0$)값과 조성비($x$)로 구한 이론 값이 잘 일치하였다. 그리고 변조 주파수 의존성을 측정한 결과 PR 신호의 형태는 변하지 않고, 신호의 크기만 변하는 것은 광조사에 따른 전기적 상태의 과도 현상에 따른 것이고, In$_{1-x}$Ga$_x$P와 GaAs의 차이는 광 캐리어의 수명의 차이로 분석된다. 온도 의존성 측정으로 In$_{1-x}$Ga$_x$P/GaAs 이종접합 시료의 균일한 변형분포와 계면상태가 양호함을 알 수 있다.

MOS蓄電器 構造의 容量-電壓 特性

裵仁鎬 嶺南大學校府設 基礎科學硏究所 1983 基礎科學硏究 Vol.3 No.-

Al-Si MOS capacitor structure has been fabricated on oxidized surface, and the capacitance-voltage characteristics have been investigated at room temperature. In the reverse bias, the calculated values of the capacitance were found to be in a good agreement with the measured values. At large values of surface potential it is evident that total charge within semiconductor consists of the electrons in the inversion region. The density of surface state is estimated as 6.2×10"cm­² and found to be positive. This was explained by the effect of interfacial layer.

외식 배달 앱 품질이 지각된 유용성 및 지속적 이용의도에 미치는 영향

배인호 한국외식경영학회 2023 외식경영연구 Vol.26 No.1

본 연구의 목적은 외식 배달 앱 품질이 지각된 유용성에 미치는 영향력을 살펴보고 이러한 지각된 유용성이 배달 앱의 지속적 이용의도에 미치는 영향 관계에 관해 검증해 보고자 한다. 본 연구를 위해 표본자료의 수집은 2022년10월24일부터 11월20일까지 외식 배달 앱을 이용한 경험이 있는 충청남도 지역의 외식 소비자를 대상으로 설문조사를 실시하였다. 표본추출은 편의표본추출법에 의해 실시되었으며, 설문지는 270부를 배포하였으며, 이 중에서 불성실하게 응답한 설문지를 제외한 총257부를 본 분석에 사용하였다. 분석결과를 살펴보면, 다음과 같다. 첫째, 외식 배달 앱 품질 중 정보품질만이 지각된 유용성에 정(+)의 유의한 영향을 미치는 것으로 나타났다. 서비스품질은 지각된 유용성에 유의한 영향을 미치지 않는 것으로 나타났다. 둘째, 지각된 유용성은 지속적 이용의도에 정(+)의 유의한 영향을 미치는 것으로 나타났다. 본 연구결과는 외식 배달 앱 품질을 통해 지각된 유용성을 향상시킴으로써 배달 앱의 지속적 이용의도를 증가시키는데 전략적 토대를 형성할 수 있을 것이다.

A Refinement System for Medical Information Extraction from Text-based Bilingual Electronic Medical Records

배인호,김진상 대한의료정보학회 2008 Healthcare Informatics Research Vol.14 No.3

Objective: Applications to extract medical information from electronic medical records(EMRs) confront some serious obstacles such as spelling errors, ambiguous abbreviations, and unrecognizable words. Those obstacles hinder the process of finding medical entities, relations, and events. We present an efficient EMR refinement system for the purpose of medical information extraction from EMRs, not just for traditional text error correction. Methods: The EMR refinement system has been designed and implemented through following steps: 1) Build domain constrained dictionary database, 2) Correct spelling errors in Korean-English EMR documents, 3) Resolve ambiguous abbreviations in the bilingual documents. The resulting EMR documents are now machine readable and can be applied to various applications including information extraction. Result: Precision rate of the refinement system for spelling error correction is 80.4% and for disambiguating abbreviations/acronyms is 94.7%. Conclusion: We developed an EMR refinement system to correct spelling errors and resolve ambiguous abbreviations as well as unrecognizable words. Our system can enhance the reliability of medical records and contribute to develop further application systems in the field of text mining and information extraction.

원통 기어로 구성된 다단 기어열의 기어비 분할법 개발

배인호,정태형 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.6

The existing methods to split overall gear ratio of the cylindrical multi-stage gear train have their own limitations to be used in practical design, and are also problematic to be implemented in a formalized algorithm. This paper proposes two types of new methods to find gear ratios best approximating the overall gear ratio. The proposed methods are quite general to be applied to the gear train having any number of stages, and offer a considerably good result in a very short time. The first method uses the random search method and the second one is based on the simulated annealing algorithm. The proposed algorithms are expected to be very useful not only as an independent program to split overall gear ratio, but also as a design sub-module for the integrated design system of multi-stage gear drives.