• Journal of Preventive Medicine and Public Health
• /
• v.24 no.3 s.35
• /
• pp.305-313
• /
• 1991

In order to investigate industrial fatigue due to visual display terminal (VDT) work of banking operations the questionnaire survey for subjective symptoms of fatigue was carried out on 470 bank clerks who had been engaged in VDT work for various length of work hours. The questionnaires comprised three groups of 10 items each, representing dullness and sleepiness (level of cerebral activation), difficulty in concentration (level of motivation) and bodily projection of fatigue. The results were as follows : 1. Of the 30 items of questionnaires, the highest percentage was accounted for by 'eye strain' (51.5% ), followed by 'feel stiffness in the neck or the shoulders'(33.4%), 'feel a pain in the low back'(26.8%), 'whole body feels tired'(19.6%) and 'feel headache'(17.9%) in the order of sequence. 2. The average weighted score for the first group of questionnaire items (dullness and sleepiness) was the largest among three groups and was followed by 'the third cup (bodily projection of fatigue) and the second item group (difficulty in concentration) in the order of sequence, suggesting the heavier mental stress of VDT work in banking operations rather than physical burden. 3. In terms of the age and sex of workers, work duration and VDT work percentage, the difference in average weighted score was noted only between sex, the score of female being larger than that of male. 4. The complaint rates of subjective symptoms showed close associations with the subjective optimums of room temperature, ventilation, illumination and noise level. 5. The significant correlation was showed between age, work duration and item of 'whole body feels tired', between VDT work percentage and items of 'eye strain' and 'feel stiffness in the neck or shoulders' and between all items of subjective symptoms.

• Research in Community and Public Health Nursing
• /
• v.19 no.1
• /
• pp.57-65
• /
• 2008

Purpose: The purpose of this study is to assess the priorities of health promotion for older adults in the rural community. The study attempts to display demographic characteristics subjective health status and chronic diseases status of the older adults. Methods: We surveyed 384 senior residents in a community via face-to-face interviews in their homes, who were selected by proportional random sampling. We analysed the frequency, multiple responses and $X^2$ by SPSS 12.0K. Results: The mean of subjective health status was $54.04{\pm}21.69$ with a maximum of 100. Our study found that the high priorities in health promotion for older adults were prevention and management of hypertension and diabetes, strengthening of joint and muscles, cancer screening and physical exercise. Prevention of depression and social activities were low priorities. Strengthening of joints and muscles was a high priority among women while smoking cessation and social activities were high priorities of men. Conclusion: In conclusion, health promotion priorities of older adults differed by gender and subjective health status. Disease-related priorities received more attention than psycho-social health priorities. This study suggests comparing the priorities regionally and nationally.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2014.02a
• /
• pp.304.1-304.1
• /
• 2014

Flat-panel displays have been growing as an essential everyday product in the current information/communication ages in the unprecedented speed. The forward-coming applications require light-weightness, higher speed, higher resolution, and lower power consumption, along with the relevant cost. Such specifications demand for a new concept-based materials and applications, unlike Si-based technologies, such as amorphous Si and polycrystalline Si thin film transistors. Since the introduction of the first concept on the oxide-based thin film transistors by Hosono et al., amorphous oxide thin film transistors have been gaining academic/industrial interest, owing to the facile synthesis and reproducible processing despite of a couple of shortcomings. The current work places its main emphasis on the binary oxides composed of ZnO and SnO2. RF sputtering was applied to the fabrication of amorphous oxide thin film devices, in the form of bottom-gated structures involving highly-doped Si wafers as gate materials and thermal oxide (SiO2) as gate dielectrics. The physical/chemical features were characterized using atomic force microscopy for surface morphology, spectroscopic ellipsometry for optical parameters, X-ray diffraction for crystallinity, and X-ray photoelectron spectroscopy for identification of chemical states. The combined characterizations on Zn-Sn-O thin films are discussed in comparison with the device performance based on thin film transistors involving Zn-Sn-O thin films as channel materials, with the aim to optimizing high-performance thin film transistors.

• Korean Institute of Interior Design Journal
• /
• v.17 no.5
• /
• pp.166-174
• /
• 2008

As the use of virtual environment for decision-making interior or architectural design has been increasingly broaden, the choice of media form-physical, objective properties of a display medium-became and important issue to take into consideration. This research deals with the effects and differences between two types of media for a virtual environment; wall projection screen(120") and PC monitor(17"). In addition, efficient adoption of the two media forms was also proposed in this research. A total of 90 subjects participated in pre-designed three experimental groups(A group: experiment with a wall projection screen, B group: experiment with PC monitor, C group: both) and answer the seating preferences, the presence inventory, and the decision confidence using a simulated virtual restaurant environment. The results are as follows: (1) seating preferences for the tables located in frequent traffic area and near other spaces such as restroom and th kitchen are significantly different by the media form. While there is no significant difference found in seating preferences for most tables except high traffic areas near entrances between the two media. This result demonstrates the effects of media type or screen size on user perception for the areas near structural or interior design elements. (2) The presence measure in this research consist of in this research consist of four factors: 'spatial presence,' 'object presence,' 'positive effects,' and 'the factor of negative effects. 'The mean values of the items involving engagement or interaction in the spatial presence factor and the object presence factor are significantly different by the media form. A higher sense of presence of presence was observed in the wall projection screen. (3) PC monitor condition was shown to provide a higher level of decision confidence. Based on the research finding, conclusions and implications are discussed.

• Journal of the Korean Institute of Educational Facilities
• /
• v.20 no.1
• /
• pp.3-14
• /
• 2013

The following research, analysis about an integral part of current elementary classroom, has been done to grasp the importance of re-organization of an elementary school classroom. For the research process 11 schools, 60 classrooms have been studied to analyze the physical elements of classroom(learning tools, equipment, etc.) to provide deeper understanding on their display, and spatial arrangement, as well as characteristic of a classroom. By looking at these analyzed elements with perspective to the grade, the number of students per class, the result turned out to be uninteresting. The observation that was made by this analysis was that there are more usages of multi-purpose desk in the classroom when there are only a few numbers of students. Also the observation could be made on the classroom wall-post. Each post had a tendency to have its defined area to be posted. The analysis showed that there are total of 24 corners can be created in the classroom, also it distinctly showed that the number of corners gets changed depending on the number of students in the classroom. The 24 corners including learning tools, equipment, and posts could be sorted to a minimum of 11 areas and a maximum of 22 areas depending on the educational purpose of the corners. The current layout of these corner and area will be the primary component that will be needed for the new coming classroom. For the future progress, depending on the system of education, the following needs to be done: (1) The installation of corners in the classroom (2) A small common-lounge area between two classrooms (3) A common-corner for each grade (4) Deeper research will be required to discuss the installation of a wide-educational area.

• Journal of Chest Surgery
• /
• v.40 no.10
• /
• pp.719-721
• /
• 2007

Patients with congenital pericardial defect display few symptoms and this is an unusual disease, so it is generally found incidentally in most of the cases. In some cases, symptoms such as chest pain are found due to partial cardiac herniation. We report here on a 14-year-old girl with dyspnea and chest pain that started during physical activity 3 months before the hospital visit. She was diagnosed with herniation of the left atrial appendage with a partial pericardium defect and she was treated with an operation.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.02a
• /
• pp.132-132
• /
• 2011

For the programming volume of PRAM, Ge2Sb2Te5(GST) thin films have been dominantly used and prepared by physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD). Among these methods, ALD is particularly considered as the most promising technique for the integration of PRAM because the ALD offers a superior conformality to PVD and CVD methods and a digital thickness control precisely to the atomic level since the film is deposited one atomic layer at a time. Meanwhile, although the IST has been already known as an optical data storage material, recently, it is known that the IST benefits multistate switching behavior, meaning that the IST-PRAM can be used for mutli-level coding, which is quite different and unique performance compared with the GST-PRAM. Therefore, it is necessary to investigate a possibility of the IST materials for the application of PRAM. So far there are many attempts to deposit the IST with MOCVD and PVD. However, it has not been reported that the IST can be deposited with the ALD method since the ALD reaction mechanism of metal organic precursors and the deposition parameters related with the ALD window are rarely known. Therefore, the main aim of this work is to demonstrate the ALD process for IST films with various precursors and the conformal filling of a nano size programming volume structure with the ALD?IST film for the integration. InSbTe (IST) thin films were deposited by ALD method with different precursors and deposition parameters and demonstrated conformal filling of the nano size programmable volume of cell structure for the integration of phase change random access memory (PRAM). The deposition rate and incubation time are 1.98 A/cycle and 25 cycle, respectively. The complete filling of nano size volume will be useful to fabricate the bottom contact type PRAM.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.02a
• /
• pp.436-436
• /
• 2011

Recently, spintronic devices with submicron structures are widely investigated to take advantage of their unique micromagnetic properties. In this work, we study the temperature dependence of exchange bias in bilayer anti-dot arrays made by depositing Co (40 nm)/Ni (5 nm) ferromagnetic bilayer on Si substrate to form anti-dot arrays with a diameter $1{\mu}m$. The anti-dot patterning was done only for the upper Co layer, while the Ni underlayer was kept unperforated. The temperature dependences of magnetoresistance (MR) and exchange bias were studied along magnetic easy and hard axes. The in-plane MR measurements were performed using a physical-property measurement system (PPMS ; Quantum Design Inc.) at various temperatures. The standard in-line four-point probe configuration was used for the electrical contacts. As temperature was varied, the MR data were obtained in which in-plane field (H=3 kOe) was applied in the directions along the hard and the easy axes with respect to the lattice plane. The temperature dependences of magnetic anisotropy and exchange bias were also studied along the magnetic easy and hard axes. As temperature decreases, the single peak splits into two peaks. While no exchange bias was observed along the magnetic easy axis, the exchange bias field steadily increased with decreasing temperature along the magnetic hard axis. These results were interpreted in connection with the magnetic anisotropy and the effect of the anti-dots in pinning domain wall motion along the respective direction.

• Journal of Sensor Science and Technology
• /
• v.15 no.1
• /
• pp.34-39
• /
• 2006

This study provides the electrical model of combustible catalytic gas sensor. Physical characteristics such as thermal behavior, resistance change were included in this model. The finite element method analysis for sensor device structure showed that the thermal behavior of sensor is expressed in a simple electrical equivalent circuit that consists of a resistor, a capacitor and a current source. This thermal equivalent circuit interfaces with real electrical circuit using two parts. One is 'power to heat' converter. The other is temperature dependent variable resistor. These parts realized with the analog behavior devices of the SPICE library. The gas response tendency was represented from the mass transferring limitation theory and the combustion theory. In this model, Gas concentration that is expressed in voltage at the model, is converted to heat and is flowed to the thermal equivalent circuit. This model is tested in several circuit simulations. The resistance change of device, the delay time due to thermal capacity, the gas responses output voltage that are calculated from SPICE simulations correspond well to real results from measuring in electrical circuits. Also good simulation result can be produced in the more complicated circuit that includes amplifier, bios circiut, buffer part.

• Polymer(Korea)
• /
• v.37 no.2
• /
• pp.184-195
• /
• 2013

Acrylic pressure sensitive adhesive (PSA) tapes were used for the automotive, the electrical and the electronic industries and the display module junction. In this study, the manufacture of high-strength structural tape used 2-ethylhexyl acrylate (2-EHA) and acrylic acid (AAC), and UV irradiation for photo-polymerization, and the semi-structural properties of acrylic PSA tape with the AAC content and inorganic filler $SiO_2$ content were investigated. The initial adhesion strength was lowered by the rigidity of molecule chains due to the use of AAC, and the adhesion strength increased with increasing wetting time. The wetability, contact angle, and SEM images of PSA tapes with various contents of AAC were determined. Without filler, the peel strength and dynamic shear strength of PSA tape showed inverse correlation but the peel strength and dynamic shear strength increased with increasing filler content. From these correlations the PSA tapes could be optimized for the applications requiring high performance.