11,625 research outputs found
Kim min-su
No full text학위논문(석사)아주대학교 보건대학원 :보건학과,2013. 2최근 직무만족도가 건강문제에 미치는 영향에 대한 연구가 다수 이루어지고 있으며 직무만족도가 높을수록 건강문제를 적게 일으킨다는 보고가 있다. 국내에서는 직무만족도와 직무스트레스 및 감정노동의 상관관계에 대한 연구들이 발표된 바 있다. 직무스트레스나 감정노동이 직무만족도에 부정적인 영향을 주고 있음은 많은 직업군에서 밝혀졌으며 직무만족도가 이직의향이나 직업적 선택, 사회친화도 등에도 영향을 미치고 있다는 것도 이전 연구들에서 밝혀진 바 있다. 그러나 우리나라에서의 직무만족도와 건강문제에 대한 연구는 아직 부족한 실정이다. 이 연구에서는 우리나라 근로자에서 직무만족도가 직장 생활 중에 일어나는 건강문제와 관련성이 있음을 밝히고자 하였다.
2006년 한국산업안전공단 산업안전보건연구원에서 전국 16개 시/도, 만 15세 이상 64세 미만 경제활동인구를 대상으로 시행한 근로환경조사를 연구에 이용하였다. 대상자들은 각각 청력손실, 시력저하, 피부 문제, 요통, 두통, 위통과 복통, 어깨와 목과 상하지 근육통, 호흡곤란, 심장질환, 상해, 스트레스, 전신피로, 불면증, 알레르기, 불안, 우울 등의 직무와 관련된 증상이 있는지 예 혹은 아니오로 응답하였다. 또한 직무만족도에 대한 질문으로 일자리의 대체적인 만족도를 매우 만족, 대체로 만족, 별로 만족하지 않음, 전혀 만족하지 않음의 4가지 중 선택하도록 하였다. 직무만족도에 영향을 미치는 직업요인을 살펴보기 위해 근무 조건으로 고용형태(정규직, 비 정규직), 주당 근무시간, 교대근무 유무, 육체노동의 유무, 회사 규모, 업종을 조사하였고 근로 환경으로 물리적, 화학적, 생물학적 위험과 환경 위험, 사회심리적 작업환경을 포함하였다. 전체 7096명의 설문 참여인원 중 1645명이 직장생활로 인해 건강이 나빠지거나 사고가 난 경험이 있다고 응답하였다. 근무 조건에서는 비 정규직인 경우와 한 주에 45시간 초과로 일하는 경우, 교대 근무를 하는 경우, 육체노동을 하는 경우, 비서비스업종에 근무하는 경우에서 직무 만족도가 통계적으로 유의하게 더 낮았다. 근로환경에서는 각각 인간공학적, 화학적, 생물학적, 환경 위험이 높은 경우 직무만족도가 유의하게 더 낮았으며 직무 요구도가 높은 경우, 직무 자율성이 낮은 경우, 상사와 동료의 지지가 낮은 경우에도 직무만족도가 낮았다. 성별, 연령, 학력, 월 평균 수입, 흡연, 음주, 근무조건과 근로환경, 작업 관련 스트레스의 유무를 보정하여 분석한 결과 직무 만족도가 낮은 경우 각 작업 관련 증상 별 위험도는 요통 1.37배(95%CI 1.11-1.70), 복통 1.64배(95%CI 1.24-2.18), 근육통 1.40배(95%CI 1.14-1.72), 전신피로 1.46배(95%CI 1.14-1.87), 불면증 1.60배(95%CI 1.17-2.18), 불안 1.46배(95%CI 1.05-2.03), 우울 2.56배(95%CI 1.78-3.68)로 관찰되었다. 이 연구 결과 근무 조건과 근로 환경에 따라 직무만족도가 유의하게 차이가 난다는 것을 확인하였다. 직무만족도가 높은 군보다 낮은 군에서 작업관련 증상이 유의하게 더 많이 관찰되었으며 이는 작업 관련 스트레스를 보정한 이후에도 일부 증상에서는 유의한 결과를 보였다. 이 연구 결과에 따라 직무만족도가 개인의 건강 문제에도 연관성이 있음을 밝힘으로서 근무 조건과 근로 환경, 작업 관련 스트레스의 개선에 대한 근거로 고려할 수 있을 것이다.Maste
Polychromatic ZnO/CdxZn1-xO composite nanorods prepared by simple chemical methods: nanoscale optical characteristics
No full textWe report the fabrication and nanoscale optical
characteristics of polychromatic ZnO/CdxZn1-xO composite nanorods
prepared by simple hydrothermal and sol-gel chemical methods.
Hydrothermally grown ~300 nm diameter and ~3.5 μm long ZnO
nanorods were coated, using the sol-gel method, with a thin CdxZn1-xO
layer having a spatially varying Cd mole fraction, where x ranged from
x = 0 to 1. Full control of the emission color, including white emission,
was achieved by simply varying the local Cd mole fraction along the
single ZnO/CdxZn1-xO nanorod. The continuous variation of the optical
band gap energy along the single nanorod was visualized using
nanoscale confocal absorption spectral imaging.1111sciescopu
Emission wavelength tuning of porous silicon with ultra-thin ZnO capping layers by plasma-assisted molecular beam epitaxy
No full textPorous silicon (PS) was prepared by electrochemical anodization. Ultra-thin zinc oxide (ZnO) capping layers were deposited on the PS by plasma-assisted molecular beam epitaxy (PA-MBE). The effects of the ZnO capping layers on the properties of the as-prepared PS were investigated using scanning electron microscopy (SEM) and photoluminescence (PL). The as-prepared PS has circular pores over the entire surface. Its structure is similar to a sponge where the quantum confinement effect (QCE) plays a fundamental role. It was found that the dominant red emission of the porous silicon was tuned to white light emission by simple deposition of the ultra-thin ZnO capping alyers. Specifically, the intensity of white light emission was observed to be enhanced by increasing the growth time from 1 to 3 min.1111sciescopu
General Synthesis of N-Doped Macroporous Graphene-Encapsulated Mesoporous Metal Oxides and Its Application as New Anode materials for Sodium-Ion Hybrid Supercapacitors
No full text2
Electrically controlled photoluminescence efficiency of organic rubrene microplates
No full textSemiconducting organic rubrene (5,6,11,12-tetraphenyltetracene) microplates (MPs) were fabricated
using physical vapor transport to study tunable photoluminescence (PL) characteristics through
an applied electric
field. The nanoscale PL intensities of a rubrene MP, which were measured via
high-resolution laser confocal microscopy (LCM), clearly depended on the applied electric
field intensity.
The LCM PL intensity of the rubrene MP sinusoidally varied with the periodic change of the electric
field.
We also observed the aging effect on the LCM PL intensity of rubrene MPs. Control of the charge
dissociation rate of photoinduced excitons by the external electric
field can be the cause of the tunable
PL efficiency of the MP.1111sciescopu
Photo-responsive transistors of CVD grown single-layer MoS2 and its nanoscale optical characteristics
No full textThe single-layer and multi-layers of MoS2 were grown using the chemical vapor deposition (CVD) method. The structural properties of the MoS2 were investigated through X-ray photoelectron spectroscopy (XPS). The optical characteristics in nanoscale of the MoS2 were determined from the analysis of Raman and photoluminescence (PL) spectra using a high-resolution laser confocal microscope (LCM). Thin-film-transistors (TFTs) using a single-layer MoS2 were fabricated, and the photo-responsive current-voltage (I–V) characteristics of the TFTs were measured with varying intensities of incident light. We observed the increase of both the photo-current and mobility with increasing the intensity of incident light. This is due to the contribution of photo-induced charge carriers from the valance band and trap states. The increasing rate of the photo-current of the TFTs with gate bias (i.e. on state) was considerably higher than that in off state, indicating the gate controlled photo-sensitive transistor. © 2016 Elsevier B.V2311sciescopuskc
Fine Control of Photoluminescence and Optical Waveguiding Characteristics of Organic Rubrene Nanorods Using Focused Electron-Beam IrradiationIrradiation
No full textWe demonstrate the fine control of the nanoscale photoluminescence
(PL) and optical waveguiding characteristics of light-emitting organic rubrene
nanorods (NRs) through focused electron-beam (E-beam) irradiation. Nanoscale
laser confocal microscope PL intensity and spectra of the focused E-beam-treated
compartments of the rubrene NR drastically varied with E-beam dose, and yellowwhite
light emission from those compartments with a specific E-beam dose was
observed. In optical waveguiding experiments, the propagation characteristics of
optical signals along the single NR were dependent on the crystalline structure of the
rubrene. For the E-beam treated NR, the waveguiding PL signals along the
crystalline a-axis had relatively higher output, indicating the major axis for the optical
energy transfer. Additionally, the waveguiding characteristics such as decay constant
along the crystalline b-axis and c-axis of the NR considerably varied at the boundary of the E-beam treatment.3511sciescopu
Expression and characterization of a novel 2-deoxyribose-5-phosphate aldolase from Haemophilus influenzae Rd KW20
No full textA codon-optimized 2-deoxy？ibose-5-phosphate aldolase (DERA) gene from Haemophilus influenzae Rd KW20 was synthesized and expressed in Escherichia coli, and the biochemical properties of its product were investigated. DERA was purified using affinity chromatography and characterized using 2-deoxyribose-5-phosphate as the substrate. Specific activity of the recombinant DERA was 34.1 Umg？1. The pH and temperature optima were 7.5 and 40°C, respectively. Additionally, the recombinant enzyme retained stability up to temperatures below 50°C. Maximal enzyme activity was observed in presence of 300 mM of acetaldehyde. The apparent Km and Vmax of purified enzyme towards 2-deoxyribose-5-phosphate were 0.14 mM and 70.42 μmol min？1 mg？1 and towards 2-deoxy-D-ribose were 24.77 mM and 1.94 μmol min？1 mg？1, respectively. For synthesis of statin intermediates, the bioconversion process for production of (3R, 5S)-6-chloro-2,4,6-trideoxy-erythro-hexose from chloroacetaldehyde and acetaldehyde using the recombinant DERA was studied and this process took 3 h for maximal conversion. This recombinant DERA could be potentially applied in the production of (3R, 5S)-6-chloro-2,4,6-trideoxy-erythro-hexose.open
A study on the gain tuning for precise position control
No full text학위논문(석사) - 한국과학기술원 : 기계공학전공, 2004.2, [ v, 39 p. ]한국과학기술원 : 기계공학전공
원자력에너지시스템의 핵확산 저항성 평가 방법론에 관한 연구
No full text학위논문(석사) - 한국과학기술원 : 원자력및양자공학과, 2007.2, [ viii, 82 p. ]The framework of proliferation resistance evaluation methodology, based on attribute analysis and scenario analysis, for nuclear energy system is suggested in order to allow for the comprehensive assessment of proliferation resistance by addressing the intrinsic and extrinsic features of nuclear energy system. Proliferation resistance is viewed within the context of the success tree model of proliferator’s diversion attempt and expressed by the value of top event probability of the success tree model. This study focused on the method that the value of top event is estimated. The methodology uses two different methods to quantify the likelihood of basic events constituting the top event. The likelihood of basic event success affected by intrinsic feature of nuclear energy system was assessed by using multi-attribute utility theory and likelihood of basic event related to the diversion detection measures was assessed by direct expert elicitation. The value of top event was calculated based on the intersection of probabilities of basic event success.
Feasibility of the methodology was explored by applying it to selected reference nuclear energy systems. System-Integrated Modular Advanced Reactor (SMART) system and Light Water Reactor (LWR) were chosen as reference systems and the value proliferation resistance of SMART and LWR were evaluated. Characteristics of inherent features and hypothesized safeguards measures of both systems were identified and used as input data to evaluate proliferation resistance. The results and conclusions are applicable only within the context of subjectivity of this methodology.한국과학기술원 : 원자력및양자공학과
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