우리나라 時價發行 制度에 關한 硏究

곽정근 숭전대학교 1988 崇營論集 Vol.7 No.1

소아의 Thiopental 직장투여 술기-진정 유도 시 BIS (bispectral index score)감시의 적용

곽정근,조규종,유지영 대한응급의학회 2007 대한응급의학회지 Vol.18 No.5

Purpose: Recently, the bispectral index monitor has been promoted as an objective measure of sedation depth during pediatric procedural sedation in the emergency department (ED). However, rectal administration of thiopental sodium for pediatric procedural sedation has not been validated. Methods: Patients aged one to seven years and undergoing primary closure procedures for simple facial and hand laceration in the ED were enrolled. Procedural sedation was performed by rectal administration of thiopental sodium. The bispectral index score and the Ramsay Sedation Scale were recorded every 10 minutes during sedation. The investigator and treating physician were blinded to bispectral index scores, which were later correlated with the Ramsay Sedation Scales values. Receiver operator characteristic (ROC) curves were conducted to determine the ability of the bispectral index score to discriminate various thresholds of sedation depth. Results: One hundred thirty paired measurements were obtained from 12 patients. The Spearman’s correlation coefficient for paired measurements, was -0.906 (95% confidence interval: [-9.8] ~ [-8.1], p<0.001). ROC curve analysis demonstrated a high discriminatory power for bi-spectral index scores in predicting the level of sedation, with areas under the curve at least 0.95 for all Ramsay Sedation Scale thresholds. Conclusion: Bispectral index monitoring can serve as a useful, objective measure of sedation depth in pediatric procedural sedation with rectal administration of thiopental sodium in the ED.

940-nm 350-mW Transverse Single-mode Laser Diode with AlGaAs/InGaAs GRIN-SCH and Asymmetric Structure

곽정근,박종근,박종현,백기종,최안식,김태경 한국광학회 2019 Current Optics and Photonics Vol.3 No.6

We report experimental results on 940-nm 350-mW AlGaAs/InGaAs transverse single-mode laser diodes (LDs) adopting graded-index separate confinement heterostructures (GRIN-SCH) and p,n-clad asymmetric structures, with improved temperature and small-divergence beam characteristics under high-output-power operation, for a three-dimensional (3D) motion-recognition sensor. The GRIN-SCH design provides good carrier confinement and prevents current leakage by adding a grading layer between cladding and waveguide layers. The asymmetric design, which differs in refractive-index distribution of p-n cladding layers, reduces the divergence angle at high-power operation and widens the transverse mode distribution to decrease the power density around emission facets. At an optical power of 350 mW under continuous-wave (CW) operation, Gaussian narrow far-field patterns (FFP) are measured with the full width at half maximum vertical divergence angle to be 18 degrees. A threshold current (I th ) of 65 mA, slope efficiency (SE) of 0.98 mW/mA, and operating current (I op ) of 400 mA are obtained at room temperature. Also, we could achieve catastrophic optical damage (COD) of 850 mW and long-term reliability of 60°C with a TO-56 package.

판교테크노밸리 조성과정과 지방자치단체의 역할

곽정근,장준철 한국지역개발학회 2015 한국지역개발학회 세미나 논문집 Vol.2015 No.3

육군 초급장교의 프리젠티즘에 관한 연구 : 직무소진의 매개효과를 중심으로

곽정근,김학수 피터드러커 소사이어티 2019 창조와 혁신 Vol.12 No.4

Recently, the phenomenon of presenteesim among junior officers who haven’t adapted to drastic changes in Military environment is emerging and is being recognized as a problem. Therefore, assuming job demand and job burnout as critical factors to presenteeism, this study examines their relationships with an additional attempt to provide possible suggestions for reducing the phenomenon of presenteeism. The result of this study shows that presenteeism behavior appears when junior officers experience job load, role ambiguity and job pressure. The second, the result of this study demonstrates that depersonalization, emotional exhaustion, and low personal accomplishment as perceived variables of job burnout partially mediate the relationship between job demand and presenteeism. Therefore, the overall findings of this study suggest to closely analyze and rearrange job demands on junior officer and to come up with job burnout managing measures(e.g., providing in-service trainings for commissioned officers, establishing clear responsibilities and limitation for authority, improving working environment) in order to reduce the phenomenon of presenteeism among junior officers and improve their leadership. 최근 육군의 급격한 병영환경 변화에 적응하지 못한 초급장교 중에 프리젠티즘현상이 나타나고 있어 문제가 되고 있다. 이에 따라 초급장교들의 프리젠티즘에 영향을 미치는 요인으로 직무요구와 직무소진을 상정하여 이들의 관계를 규명하고, 프리젠티즘 현상의 저감 대책을 마련하고자 하였다. 연구 결과 첫째, 육군 초급장교가 직무부담과 직무압박 그리고 역할모호성을 느낄 때 직접적으로 프리젠티즘 행동이 나타나고 있음을 알 수 있었다. 둘째, 직무소진의 선행변수인 비인격화, 정서적 소진, 자아성취감 감소는 직무요구와 프리젠티즘 간의 관계를 부분 매개하는 것으로 나타났다. 따라서 육군 초급장교에게 나타나고 있는 프리젠티즘 현상을 감소시키기 위해서초급장교들에게 부여되고 있는 직무요구를 면밀히 분석해서 조정하고, 임관 이후재교육과 명확한 책임과 권한의 한계 설정, 복무여건 개선 등의 직무소진 관리 대책이 요구된다.

850 nm GaAs/AlGaAs MQW LD의 Lateral-mode 특성 연구

양정택,곽정근,최안식,김태경,최우영,Yang, Jung-Tack,Kwak, Jung-Geun,Choi, An-Sik,Kim, Tae-Kyung,Choi, Woo-Young 한국광학회 2021 한국광학회지 Vol.32 No.2

850 nm 대역의 발진 파장을 갖는 GaAs/AlGaAs 다중양자우물 레이저 다이오드의 lateral-mode 특성과 이 특성이 출력 광파워 kink에 미치는 영향을 조사하였다. 이를 위해 전기적-열적-광학적 시뮬레이션을 self-consistent하게 수행하고, 제작된 레이저 다이오드 소자들을 측정하였다. 연구 결과를 바탕으로 높은 출력 파워에서도 single lateral-mode를 유지해서 좋은 beam quality를 유지할 수 있는 최적의 P-cladding 두께를 결정하였다. The lateral-mode characteristics of 850-nm GaAs/(Al,Ga)As multiple-quantum-well laser diodes and their influence on the kinks in output optical power are investigated. For the investigation, self-consistent electro-thermal-optical simulation and measurement of fabricated devices are used. From this investigation, the optimal P-cladding thickness that provides single-lateral-mode operation is determined, so that high beam quality can be achieved even at high output powers.

Lateral Far-field Characteristics of Narrow-width 850 nm High Power GaAs/AlGaAs Laser Diodes

양정택,곽정근,최안식,김태경,최우영 한국광학회 2022 Current Optics and Photonics Vol.6 No.2

We investigate the lateral far-field pattern characteristics, including divergence angle change and farfield pattern analysis as output power increases, of narrow-emitter-width 850 nm GaAs/AlGaAs laserdiodes (LDs). Each LD has a cavity of 1200 and 1500 μm and narrow emitter width of 2.4 μm for the top and 4.6 μm for the bottom. The threshold currents are 35 and 40 mA, and L-I kinks appear at powerlevels of 326 and 403 mW, respectively. The divergence angle tends to increase due to the occurrence of first-order lateral mode and the thermal lensing effect. But with the L-I kink, the divergence angle decreases and the far-field pattern becomes asymmetric. This is due to coherent superposition between the fundamental and the first-order lateral mode. We provide detailed explanations for these observations based on high-power laser diode simulation results.

실리카 졸-겔 공정에 의한 연자성 복합체 분말 성형

김호형,곽정근,이흥렬 한국표면공학회 2015 한국표면공학회 학술발표회 초록집 Vol.2015 No.11

고둥 섭취 후 발생한 일가족 테트라민 중독 1례

이창원,곽정근,박경춘,유지영,유지영,조규종,Lee, Chang-Won,Kwak, Jung-Keun,Park, Kyung-Choon,Ryu, Ji-Yeong,You, Ji-Young,Cho, Gyu-Chong 대한임상독성학회 2007 대한임상독성학회지 Vol.5 No.1

Certain parts of shellfish contain poisonous substances and cause intoxication. Tetramine toxin is found in the salivary gland of Neptunea. Three family members were admitted to the hospital with chief complaints of dizziness and blurred vision, gait disturbance, and spasms of the lower extremities after ingesting Neptunea. Physical examination revealed sluggish pupil light reflexes, but laboratory studies were normal. Symptoms were completely resolved within 24 hours after injection of atropine. We report a case of three patients with dizziness and blurred vision, gait disturbance, and spasms of the lower extremities due to Neptunea tetramine toxin.