• Journal of Korean Neurosurgical Society
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• v.61 no.4
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• pp.530-536
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• 2018

We present two cases of unexpected postoperative intractable cervicalgia due to over-sized implant insertion during simple anterior cervical decompression and fusion (ACDF) or artificial disc replacement (ADR). These patients experienced severe cervicalgia mostly related to their neck motion even after standard cervical operations. In both cases, the restored disc heights after the operations were prominently greater than the preoperative disc heights. The patients had not responded to any of the conservative treatments, and unloading of these excessively distracted segments through ultimate revision surgery led to dramatic pain relief. This report emphasizes the increase in distractional forces that takes place after a standard ACDF or ADR, as well as the importance of a proper sized implant. It also includes the reviews of other biomechanical or clinical reports dealing with this issue, thereby cautioning the surgeons not to disregard these factors, which might have an adverse effect in patients with cervicalgia even after radiographically successful cervical procedures.

• Environmental Engineering Research
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• v.22 no.4
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• pp.377-383
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• 2017

A tube-type ceramic membrane for microfiltration was developed, and the membrane module comprised of three membranes was also applied to biological carbon and nitrogen removal processes for post-treatment. Manufacturing the microfiltration membrane was successful with the structure and boundary of the coated and support layers within the membrane module clearly observable. Total kjeldahl nitrogen removal from effluent was additionally achieved through the elimination of solids containing organic nitrogen by use of the ceramic membrane module. Removal of suspended solids and colloidal substances were noticeably improved after membrane filtration, and the filtration function of the ceramic membrane could also easily be recovered by physical cleaning. By using the ceramic membrane module, the system showed average removals of organics, nitrogen, and solids up to 98%, 80% and 99.9%, respectively. Thus, this microfiltration system appears to be an alternative and flexible option for existing biological nutrient removal processes suffering from poor settling performance due to the use of a clarifier.

• The Research Journal of the Costume Culture
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• v.17 no.1
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• pp.90-104
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• 2009

If people want to project a successful personal style, hair style might play a big role as well as clothing. The purpose of this study was to observe hair behavior according to demographic variables, and to analyze correlation between desired hair image and clothing image sought. Questionnaires were distributed to 600 females aged $20s{\sim}40s$, using a convenient sampling method. Only 556 reliable questionnaires were selected for statistical analysis. Correlation r, ANOVA and Chi-square were used to analyze the data, using the SPSS program. There was a significant association between hair style and occupation. Career woman preferred roll straight perm treated hair, students preferred general perm treated hair and full time house wives preferred general wave perm treated. The medium layer cut was the most preferred cut style. People want to give different accents in hair styling with occupation and age variable. Certain desired clothing image had a high correlation with desired hair style image. Those who people want to express sexy, and bohemian image through clothing, they also want to create those image in hair styling with a high correlation(r=0.683, r=0.704).

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.3
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• pp.24-31
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• 2004

A successful on-line monitoring system for conventional machining operations has the potential to reduce cost, guarantee consistency of product quality, improve productivity and provide a safer environment for the operator. In fine-shape machining, typical signs of tool problems such as vibration, noise, chip flow characteristics and visual signs are almost unnoticeable without the use of special equipment. These characteristics increase the importance of automatic monitoring in fine-shape machining, however, sensing and interpretation of signals ar more complex. In addition, the shafts of the mini-tools break before the typical extensive cutting edge of the tool gets damaged. In this study, the existence of a relationship between the characteristics of the cutting force and tool usage was investigated, and tool breakage detection algorithm by LabVIEW was developed and the following results are obtained. It was possible to use a relative error compare which mainly used in established experiment and investigated tool breakage detection algorithm in time domain which can detect AE and cutting force signals more effective and accurate.

• KSBB Journal
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• v.8 no.2
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• pp.97-103
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• 1993

This study was investigated as a step for the purpose of successful introduction of cytoplasmic inherited characters between the different plants. Cytoplasts were separated from the protoplasts of CMS(cytoplasmic male sterility) line such as MS Burley 21 which carried from Nicotiana megalosiphon. The cytoplasts were fused to protoplasts derived from Nicotiana tabacum Br 64 with PEG(polyethylene g1yco1). The cytoplasts were separated by density gradient centrifugation. Efficient separation of cytoplasts depended on the difference of specific density of gradient solution. However, the iso-osmolality of gradient solution was not important to separate the cytoplasts. The cells for a cybrid were fused with 50% concentration of PEG.

• Transactions of Materials Processing
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• v.26 no.3
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• pp.174-180
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• 2017

In this study, a new spot welding with electric resistance heated dies is suggested for the spot welding of non-ferrous metal plates for drawing and concurrent spot welding. This welding method involves two heating processes such as heating by conduction of electric resistance heated dies and heating by resistance between contacted surfaces of two plates by welding current induced to copper dies for the fusion of contacted metal. This welding process has welding variables such as current induced in heated and copper dies, the inner diameters of heated dies, and edge shape of the copper dies. Experimental conditions for each current should be established to get successful welding strength. The welding strength could reach to the desired value in industrial fields under the following conditions of contact diameters of heated dies in this case of overlapped aluminum5052 plates with 0.3-mm thickness: inner and outer diameters of 5.0 and 16mm, respectively; diameter of copper dies, 5.0mm; heating current, 6.8kA in heated steel dies; welding current, 8.6 kA in copper dies.

• Mycobiology
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• v.39 no.4
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• pp.272-277
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• 2011

Chemical mutagenesis of basidiospores of Hypsizygus marmoreus generated new mushroom strains. The basidospores were treated with methanesulfonate methylester, an alkylating agent, to yield 400 mutant monokaryotic mycelia. Twenty fast-growing mycelia were selected and mated each other by hyphal fusion. Fifty out of the 190 matings were successful (mating rate of 26.3%), judged by the formation of clamp connections. The mutant dikaryons were cultivated to investigate their morphological and cultivation characteristics. Mutant strains No. 3 and No. 5 showed 10% and 6% increase in fruiting body production, respectively. Eight mutant strains showed delayed and reduced primordia formation, resulting in the reduced production yield with prolonged cultivation period. The number of the fruiting bodies of mutant No. 31, which displayed reduced primordial formation, was only 15, compared to the parental number of 65. Another interesting phenotype was a fruiting body with a flattened stipe and pileus. Dikaryons generated by mating with the mutant spore No. 14 produced flat fruiting bodies. Further molecular biological studies will provide details of the mechanism. This work shows that the chemical mutagenesis approach is highly utilizable in the development of mushroom strains as well as in the generation of resources for molecular genetic studies.

• Nuclear Engineering and Technology
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• v.20 no.4
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• pp.246-252
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• 1988

Experiments on the hydrogen gas breakdown for plasma initiation in the KAERIT tokamak are described. The influence of the applied loop voltage, toroidal magnetic field, gas filling pressure, error magnetic field, and preionization is studied. It is concluded that the magnitude of the error field is the most important factor for successful discharge initiation. The gas breakdown voltage becomes minumum when the external compensating field most effectively corrects the net error field. Even though preionization effect is not prominent, it is exhibited more easily in the case of worse confinement. Discharge initiation conditions experimentally determined are compared with those calcuated from a theoretical model. Some other unknown physical processes maintain the operation range somewhat narrower than predicted by the present theoretical model. However, this model is adequate for the breakdown phase of tokamaks.

• The Journal of Korean Association of Computer Education
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• v.15 no.6
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• pp.11-20
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• 2012

Interest in creativity and fusion in education has led to a lot of research on integrated education. Most of those research were related to integrated education model and educational contents development, so there were insufficient research on planning a course for integrated education. In this study, we developed an integrated education framework as an guidance for teachers on how to plan a course for integrated education. With this, we analyzed successful cases of integrated education. In the result of analysis, we figured out the relations and characteristics between three course types of subjects and four participation types of teachers. On the findings, we suggested an integrated education framework composed of four stages focused on course plan and proposed some considerations for each stage.

• Journal of Sensor Science and Technology
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• v.22 no.5
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• pp.364-368
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• 2013

Vibrational energy harvester based on piezoelectricity has been expected to be the dominant energy harvesting technology due to the advantages of high conversion efficiency, light weight and small size, night operation, etc. Its commercialization is just around the corner but the integration with power management electronics should be solved in advance. In this paper, therefore, fully-integrated design environment for piezoelectric energy harvesting systems is presented to assist co-design with the power management electronics. The proposed design environment is capable of analyzing the energy harvester including the package-induced damping effects and simulating the device and its power management electronics simultaneously. When the developed design environment was applied to the fabricated device, the simulated resonant frequency matched well with the experimental result with a difference of 2.97% only. Also, the complex transient response was completed in short simulation time of 3,001 seconds including the displacement distribution over the device geometry. Furthermore, a full-bridge power management circuit was modeled and simulated with the energy harvester simultaneously. Therefore the proposed, fully-integrated design environment is accurate and fast enough for the contribution on successful commercialization of piezoelectric energy harvester.