• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.881-885
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• 2004

We report a method for making a device on which semi-conducting single-walled carbon nanotubes are attached selectively between two metal electrodes. This method is divided two processes. First we can connect a rope of single-walled carbon nanotubes(SWNTs) between two electrodes using the electric field. But a SWNTs' rope obtained by the first process was composed of a few of metallic and semi-conducting SWNTs together. The second process is to burn the metallic and semi-conducting nanotubes through applying a voltage. As a result, we can obtain a semi-conducting SWNT device. To make the patterned electrodes, we deposited $SiO_2$(150nm) on a wafer. After then, we made a patterned samples with Ti(200 $\AA$)/Au(300$\AA$). We empirically obtained a electric condition 0.66 $V_{pp}$ /${\mu}{\textrm}{m}$@5MHz. From this result, we verified that most of current go through the metallic nanotubes in this device. When we apply DC voltage between two electrodes, the metallic carbon nanotubes are burnt. Finally, we can obtain a semi-conducting nanotube device which we desire to make. We got the I-V characteristic graph which has shown the semi-conducting property. We hope to apply to the various applications using this selective semi-conducting carbon nanotube deposition method.ethod.

• Journal of the Korean Professional Engineers Association
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• v.18 no.3
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• pp.1-20
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• 1985

The traffic congestion of Seoul city has been one of the most serious problems to be settled since the advent of 1970s. As a means to mitigate traffic mess, the authority concerned launched the construction of subway line 3 and 4 in 1980. The two Subway lines slated for completion by 1985 cross each other and run north-south direction, passing through the metropolitan area of Seoul city fraught with high-rise edifices and large-scale shopping centers, and, in order to reduce blasting vibration, NATM was executed for a distance of 10 Km, instead of ASSM previously employed when subway line 1 and 2 were constructed. Tunnel blastings were implemented, preceded by classifying the rocks at construction area into five categories, namely, hard rock, semi-hard rock, weak rock weathered rock and silt and by calculating their respective specific charges through standard test blastings, by employing the pre-splitting and smooth blasting with drilling patterns of burn cut type, so as not to cause damages to surface structures. Most of explosives used were the slurry of low specific gravity and low velocity, and the firings executed by the use of milli-second detonators. Empiric formula were also formulated to check blasting vibrations, based on the vibration allowable values of West Germany standard, for the application to vulnerable construction zones. Should the two lines be placed for public service in 1985, about 40% of the total traffic population of Seoul city amounting to 15 million as of 1984 is estimated to be carried by subway with no difficulties.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.918-921
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• 2001

In grinding process, the heat of $1200^{\circ}$~$1500^{\circ}$ on the grinding area between grinding wheel and workpiece is generated. It decreases the surface integrity of workpiece and causes the thermal damages such as the deformed layer, residual stress and grinding burn. Generally coolant is widely used for preventing the heat generation on the grinding area, but it deteriorates the working condition by polluting the atmosphere of workplace and in the end pollutes the environment. The grinding methods using the compressed cold air and mist are the cooling methods to substitute conventional coolant. They can decrease the environmental pollution through not using coolant any more or minimizing it. In this study, the cooling effects of grinding methods using the compressed cold air and mist have been investigated. The grinding system equipped with the water bathe and mist spray nozzle was developed. The energy partition to workpiece through measuring the temperature on the workpiece surface was calculated. The surface integrity of workpiece and thermal damage like the deformed layer were analyzed.

• International Journal of Automotive Technology
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• v.2 no.2
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• pp.63-75
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• 2001

This paper describes the development of THC reduction technologies compliant with SULEV regulations. Technologies embodied by the developmental work include improvement of fuel spray atomization, quick warm-up through coolant control shut of, and acceleration of fuel atomization for the fast rise of cylinder head temp inside the water jacket as well as the improvement of combustion state. The technologies likewise entail reduced HC while operating in lean A/F condition during engine warm-up with the cold lean burn technology, individual cylinder A/F control for improvement of catalytic converting efficiency, after-treatment such as thin-wall catalyst, HC-adsorber and EHC and etc, through vehicle application evaluation in cold start. We carried out an experimental as well as a practical study against SULEV regulations, and the feasibility of adopting these items in vehicle was likewise investigated.

• Journal of Radiation Protection and Research
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• v.36 no.4
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• pp.174-182
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• 2011

With the reactor operation conditions - 4.3 wt% $^{235}U$ initial enrichment, burn-up 55,000 MWd/MTU, average power 34 MW/MTU for three periods burned time for 539.2 days per period and cooling time for 100 hours after shut down, to set up the condition to determine the minimum height (depth) of spent fuel storage pool to shut off the radiation out of the spent fuel storage pool and to store spent fuels safely, the dose rate on the specific position directed to the surface of spent fuel storage pool induced by the neutron and gamma-ray from spent fuels are evaluated. The length of spent fuel is 381 cm, and as the result of evaluation on each position from the top of spent fuel to the surface of spent fuel storage pool, it is difficult for neutrons from spent fuels to pass through the water layer of maximum 219 cm (600 cm from the floor of spent fuel storage pool) and 419 cm (800 cm from the floor of spent fuel storage pool) for gamma-ray. Therefore, neutron and gamma-ray from spent fuels can pass through below 419 cm (800 cm from the floor) water layer directed to the surface of spent fuel storage pool.

• 재활복지
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• v.21 no.2
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• pp.217-231
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• 2017

We have to consider two parts of the evaluation and treatment for the patients with head and neck burns. The primary consideration is swallowing function for nutrition supply for them and the next is speech function for efficient communication and aesthetic impression of them. The purpose of this study is to summarize the preliminary questions of Communication Screening Protocols which can help understand comprehensively on swallowing disorder, motor speech disorder and voice disorder of patients with head and neck burns. We divided the evaluation into 4 evaluation areas including 'oral mechanism', 'respiration/voice', 'articulation', and 'swallowing' by referring to overseas studies dealing with various communication disorders caused by burns, and prepared the final questionnaires by conducting the content validity verification by five expert (speech & language pathologist). The range of Content Validity Index was shown relatively appropriate with .50~.84. There was a conflict of opinions in experts whether the items in the areas of respiration/voice and swallowing may be appropriate, whereas there was no different view of the oral mechanism and articulation area. Through the different characteristics of communication difficulties of patients with head and neck burns, we expect it will be modified appropriately according to the patients through evaluation of burn patients by type and severity.

• Archives of Plastic Surgery
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• v.34 no.3
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• pp.409-412
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• 2007

Purpose: Percutaneous Kirschner wire fixation is common method for hand fracture. It is simple but has risk of ascending infection through the pin and bony injury by multiple drilling. Ascending infection through pin tract is mostly superficial and can be treated with antibiotics and aseptic dressing. This is a case review of subacute osteomyelitis on phalangeal bones after Kirschner wire fixation with literature review. Methods: A 40-years-old man with distal phalangeal fracture on right second finger is presented. He went to a local clinic and had percutaneous Kirschner wire fixation under local anesthesia. He was transferred to our hospital for ulcerative wound on DIP joint at 4 weeks after operation. Radiography showed osteolytic change around medulla of middle and distal phalanges, leading to diagnosis of a subacute osteomyelitis. We treated it with amputation at the level of shaft of middle phalanx. Results: The postoperative course was uneventful. We thought several possible reasons for osteomyelitis in our case. First, it could resulted from ascending infection through the wire. Second, it could be resulted from a bony burn by repeated drilling. And bony necrosis could be a consequence of arterial insufficiency caused by 2 pin insertion. Conclusion: We suggest that a precise pinning based on accurate anatomical understanding is required for a percutaneous Kirschner wire fixation. The frequency of drilling should be minimized. Careful observation and patient education for pin site care are essential.

• Journal of the Korea Safety Management & Science
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• v.22 no.2
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• pp.57-71
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• 2020

The purpose of this study is to explore the effects of fire officers' experience of traumatic events and subsequent forest healing on their occupational burnout. The results are as follows: First, the experience of traumatic events, social and psychological healing, and relieving stress by strolling had a significant effect on burnout. The more fire officers are exposed to traumatic events, the more they lose self-control in social and psychological aspects, and the lower the level of stress relieved through strolling, the higher the level of burnout. Thi sresult suggests that the more fire office rsare called out for fire fighting, the more they see their colleagues with severein juries, and the higher the level of mental and physical an xiety, the more they areex hausted. Moreover, for es thealing help store duce the irmental and physi calfatig uecaused by traumatic events, thu spreven ting them from suffering from burn out. Second, the experience of traumatic events, social and psychological healing, and relieving stress by strolling had a significant impact on occupational stress. The more fire officers are exposed to traumatic events, the more they lose self-control in social and psychological aspects, and the lower the level of stress relieved through strolling, the higher the level of occupational stress. This result indicates that to relieve job stress caused by fire fighting, increased forest healing activities, including various programs such as psychotherapy, developing interpersonal relationships and self-control, and creating a positive mind-set, can reducejobstress and help fire officers recover from it. Lastly, job stress had a mediation effect on the effects of the experience of traumatic events and forest healing on burnout. This implies that burnout can be prevented when fire officers gain high emotional stability through social and psychological healing and stress-relief strolling over a traumatic experience, and stronger support from the organization and family can keep them from being emotionally drained, thus contributing to the prevention of burnout.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.1
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• pp.96-101
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• 2021

Arduino is one of the open source microcontroller projects, and Arduino boards using AVR microcontrollers are commonly used. In general, AVR microcontrollers use ISP (In System Programming) upload, but in Arduino, serial upload through a bootloader is basically used, and a dedicated microcontroller is built into the board for this purpose. In order to use the ISP upload in Arduino, a dedicated upload device is required, which is not included in the Arduino board. In this paper, we propose a unified programmer that can handle ISP upload and serial upload through one dedicated microcontroller, and show that ISP and serial upload are possible using the unified programmer. In addition, the proposed unified programmer works as a USB-serial converter, supports serial communication with a computer, and it is also possible to burn the Arduino bootloader. All operations of the unified programmer can be confirmed through the experimental results.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.5
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• pp.43-57
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• 2022

This study aims to classify forest fire-affected areas, identify forest types by the intensity of forest fire damage using multi-time Landsat-satellite images before and after forest fires and to analyze the effects of artificial restoration sites and natural restoration sites. The difference in the values of the Normalized Burned Ratio(NBR) before and after forest fire damage not only maximized the identification of forest fire affected and unaffected areas, but also quantified the intensity of forest fire damage. The index was also used to confirm that the higher the intensity of forest fire damage in all forest fire-affected areas, the higher the proportion of coniferous forests, relatively. Monitoring was conducted after forest fires through Normalized Difference Vegetation Index(NDVI), an index suitable for the analysis of effects by restoration type and the NDVI values for artificial restoration sites were found to no longer be higher after recovering the average NDVI prior to the forest fire. On the other hand, the natural restoration site witnessed that the average NDVI value gradually became higher than before the forest fires. The study result confirms the natural resilience of forests and these results can serve as a basis for decision-making for future restoration plans for the forest fire affected areas. Further analysis with various conditions is required to improve accuracy and utilization for the policies, in particular, spatial analysis through forest maps as well as review through site checks before and immediately after forest fires. More precise analysis on the effects of restoration will be available based on a long term monitoring.