• Title/Summary/Keyword: literatures

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Tumors of the Parotidomasseteric Area Associated with Inadequate Primary Treatment: Report of 2 Cases (부적절한 일차 처치와 연관된 이하선 종양 2례)

  • Song, Jin Woo;Choi, Hwan Jun;Kim, Mi Sun;Ahn, Hyung Sik;Kim, Jun Hyuk;Lee, Young Man
    • Archives of Plastic Surgery
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    • v.33 no.6
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    • pp.764-768
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    • 2006
  • Purpose: Parotid neoplasia are relatively frequent, representing approximately 3% of all tumors in the head and neck regions. But incomplete resection and misdiagnosis of parotid gland is followed by multiple tumor invasion, tumor recurrence, and other iatrogenic tumor formation. In patients undergoing parotidectomy for confirmed or suspected malignancy, the traditional or modified rhytidectomy incision may prove suboptimal because it does not easily lend itself to a continuous neck dissection. Similarly, patients with tumors of the anterior accessory lobe or patients with large anterior tumors may also require the modified Blair incision for adequate surgical exposure. This report serves to revisit the topic of accessory and parotid gland neoplasms to emphasize proper management, particularly the surgical aspects, so that consequences of recurrence are avoided. Methods: This is a retrospective review of our experience with two cases of parotid tumors; one accessory parotid gland neoplasm and one parotid gland neoplasm. We report the case of parotid tumor and epidermal cyst in a 54-year old male patient and the case of case of recurrent parotid tumor with local invasion in 30-year old male patient. Results: All were removed through a modified Blair incision. Pathologic report notified that One was found pleomorphic adenoma and epidermal cyst, and the other one pleomorphic adenoma with subcutenous invasion. The patients recovered well without any complication such as infection, hematoma, facial nerve palsy, and necrosis of skin flap. Patients were discharge POD#7. Patients were followed up to for 1 year and they have no sign of recurrence. Conclusions: A high index of suspicion, prudent diagnostic skills(including fine-needle aspiration biopsy, CT, US), and meticulous surgical approach are the keys to a successful management of these lesions. We experienced two cases of parotid neoplasia, in the treatment of tumor reccurence & iatrogenic tumor arising from the parotid gland and are presented with the review of literatures.

Investigation of Cognitive Model of Task Commitment on Biology Classification Inquiry (생물 분류 탐구에서 과제 집착의 인지적 모형 규명)

  • Kwon, Seung-Hyuk;Kwon, Yong-Ju
    • Journal of Science Education
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    • v.37 no.1
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    • pp.170-185
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    • 2013
  • The purpose of this study is to investigate a cognitive model of task commitment on biology classification inquiry. To achieve this goal, first, this study analyzed several literatures on task commitment in biology inquiry, and invented the tentative model of the task commitment. To investigate a tentative model invented, 2 main tasks were developed. These tasks were administered to 8 high-school students, first grade. Raw protocols were collected by thinking aloud method and a retrospective interview method. Collected protocols were converted to segmented protocols and coded by analyzing frame based invented model. The codes were analyzed. As a result, some problems were discovered, tentative model were revised. New analyzing frame based on Improved model were composed, and raw protocols were re-analyzed. Finally, a cognitive model of task commitment on biology classification inquiry was investigated. The investigated cognitive model of task commitment on biology classification inquiry was constructed 3 steps, 'Task commitment Induction', 'Task commitment Reinforcement', 'Task commitment Maintenance'. And each steps were consisted of several sub-factor. And commitment component were changed in each steps. Through this results, base information for strategy that improvement task commitment on biology classification inquiry is provided. Furthermore, the cognitive model of task commitment on biology classification inquiry will assist on evaluation and feedback by stage on task commitment.

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The utilization of antibiotics and the treatment of bacterial diseases in fish (항생제 사용과 세균성 어류질병의 치료)

  • Jeong, Hyun-Do;Chun, Seh-Kyu
    • Journal of fish pathology
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    • v.5 no.1
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    • pp.37-48
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    • 1992
  • Antibiotics are chemical substances produced by various species of microorganisms that suppress the growth of other microorganisms or may destroy them. Among the more than 4000 antibiotics that has been identified, about 20s are using as the therapy of infectious fish diseases. There are several methods used to classify and group antibiotics, and the most common classification has been based on chemical structure and proposed mechanism of action. The effect of antibiotics may be determined by the kind of fish pathogens and by the external environment surrounded the infected fish. It implies that the kind of antibiotics and its application method should be decided after the determination of the reasons of fish disease. The uncontrolled usages of antibiotics may induce the selection of resistant mutants appeared spontaneously and present in any group of bacteria. The epidemic spread of such antibiotic resistant strains of fish pathogenic bacteria already has been reported in various districts of japan. Importantly, transferable drug resistant(R) plasmids were detected in strains of most of fish pathogens. Based on those reports, the antimicrobial resistance appears to be a rapidly emerging problem in the fish industry on the country. The expanding literatures on the pharmacokinetics, clinical trials, withdrawal periods and efficacy of environmental effect for the commonly using antibiotics have met the needs of data for the practical application of antibiotics. However, the most important thing for the treatment of fish diseases would be the communication and exchanging of information between the site of aquaculture and the diagnostic laboratory.

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The Effects of Top and Bottom Lids on the Natural Convection Heat Transfer inside Vertical Cylinders (수직 원형관 내부에서 발생하는 자연대류 열전달에서 상·하단 마개의 영향)

  • Kang, Gyeong-Uk;Chung, Bum-Jin
    • Journal of Energy Engineering
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    • v.20 no.3
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    • pp.242-251
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    • 2011
  • The effects of top and bottom lids on the natural convection heat transfer phenomena inside vertical cylinders were investigated experimentally for $Ra_{Lw}$ from $9.26{\times}10^9$ to $7.74{\times}10^{12}$. Using the concept of analogy between heat and mass transfer, a cupric acid-copper sulfate electroplating system was employed as mass transfer experiments replacing heat transfer experiments. The natural convection heat transfer of both-open cylinders in laminar and turbulent flows was in good agreement with the existing heat transfer correlations developed for vertical plates. The effects of top and bottom lids on the heat transfer rates were very similar to the studies of Krysa et al. and Sedahmed et al. and Chung et al. With the copper lids, the bottom-closed cavity showed the highest heat transfer rates and then followed both-closed, top-closed, both-open ones in both laminar and turbulent flows. However with the acryl lids, the similar trends were observed except that the heat transfer rates for both-open were higher than top-closed one. The use of the copper lids increased the heat transfer rates compared to the acryl lids due to the hydrodynamic interaction of the flows developed for the different heated faces. This study extended the ranges of flow conditions of the existing literatures and proposed the empirical correlations.

A Study on Job Analysis for the Development of Vocational Education & Training Curriculum for the Environmental field (환경분야 직업교육훈련과정 개발을 위한 직무분석 기초 연구)

Development of Questionnaire for Automobile Seat Comfort Evaluation (자동차 시트의 안락도 평가를 위한 문항개발에 관한 연구)

  • Kim, Jung-A;Na, Ho-Jun;Cho, Dong-Hwan;Shin, Yun-Ho;Park, Se-Jin;Kim, Jin-Ho
    • Science of Emotion and Sensibility
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    • v.13 no.2
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    • pp.381-390
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    • 2010
  • The automotive seat comfort evaluation was to begin a key aspect in seat design. It depended largely on the basic mechanical aspect such as geometric parameters of seat, choice of suspension system and cushion material used. Until recently, seat comfort evaluation advanced to evaluate subjective sensitivity of human. The external literatures showed in the last decade, there have been very few attempts to establish and document automotive seat comfort evaluation. In 2006 Smith, D. proposed the statistically reliable tool in giving a numeric rating for set comfort and the tool was used in the many country. On the other hands, we, in Korea, had not the reliable tool for the automotive seat comfort evaluation. So that, we studied to develope the questionnaire for seat comfort evaluation based on Smith, D.(2006) and some studies. As a result, we developed 36 contents for the automotive seat comfort evaluation with the help of professional in Korean automotive industry. Here, 36 contents were identified as the dimensions that represent the human sensitivity and psychological feeling on comfortable seat. Also, we derived the priorities for the 36 contents by using analytic hierarchy process (AHP), based on the judgments of 30 experts and drivers. This study will help the designers and developers clarify the conceptual and abstract aspect of the design evaluation by proposing a more systematic and process-oriented method.

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A Study on the Effects of Design Parameters of Vertical Ground Heat Exchanger on the Borehole Thermal Resistance (수직밀패형 지중열교환기의 설계인자가 보어홀 전열저항에 미치는 영향에 관한 연구)

  • Chang, Keun Sun;Kim, Min-Jun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.10
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    • pp.128-135
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    • 2018
  • Currently, vertical closed ground heat exchangers are the most widely utilized geothermal heat pump systems and the major influencing parameters on the performance of ground heat exchangers are the ground thermal conductivity(k) and borehole thermal resistance($R_b$). In this study, the borehole thermal resistance was calculated from the in-situ thermal response test data and the individual effects of design parameters (flow rate, number of pipe, grout composition) on the borehole thermal resistance were analyzed. The grout thermal resistance was also compared with the correlations in the literatures. The borehole thermal resistance of the investigated ground heat exchanger results in 0.1303 W/m.K and the grout thermal resistance (66.6% of borehole thermal resistance) is the most influencing parameter on borehole heat transfer compared to the other design parameters (pipe thermal resistance, 31.5% and convective thermal resistance, 1.9%). In addition, increasing the thermal conductivity of grout by adding silica sand to Bentonite is more effective than the other design improvements, such as an increase in circulating flowrate or number of tubes on enhancing borehole heat transfer.

A preliminary study on economical efficiency of a room-and-pillar excavation method in comparison with 2-arch tunnelling method (2아치 터널 굴착 공법과의 비교를 통한 주방식 굴착 공법의 예비 경제성 검토 연구)

  • Lee, Chulho;Chang, Soo-Ho;Ahn, Sung-Youll;Shin, Hyu-Soung
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.15 no.6
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    • pp.599-612
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    • 2013
  • This study aims to investigate an economical efficiency of two excavation methods with respect to the room-and-pillar method for the underground space and conventional excavation method, i.e. 2-arch tunnelling method. For feasibility study, an excavation cost for both room-and-pillar method and 2-arch tunnelling method was estimated when the same space in operation was required. It was assumed that properties of reinforcements and rock were adopted from literatures. However, an excavation shape of the room-and-pillar method was assumed not to be the rectangular shape which is a general type in the room-and-pillar method but to be an arch shape in order to compare with the conventional excavation method (2-arch tunnelling) and to achieve the maximum bearing capacity of the structure during excavation. Consequently, the wider space in use or required and the better condition of rock we assumed, the more economical advantage we have in the room-and-pillar method than the 2-arch tunnelling method.

Stability of Partial Nitrification and Microbial Population Dynamics in a Bioaugmented Membrane Bioreactor

  • Zhang, Yunxia;Xu, Yanli;Jia, Ming;Zhou, Jiti;Yuan, Shouzhi;Zhang, Jinsong;Zhang, Zhen-Peng
    • Journal of Microbiology and Biotechnology
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    • v.19 no.12
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    • pp.1656-1664
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    • 2009
  • Bioaugmentation of bioreactors focuses on the removal of numerous organics, with little attention typically paid to the maintenance of high and stable nitrite accumulation in partial nitrification. In this study, a bioaugmented membrane bioreactor (MBR) inoculated with enriched ammonia-oxidizing bacteria (AOB) was developed, and the effects of dissolved oxygen (DO) and temperature on the stability of partial nitrification and microbial community structure, in particular on the nitrifying community, were evaluated. The results showed that DO and temperature played the most important roles in the stability of partial nitrification in the bioaugmented MBR. The optimal operation conditions were found at 2-3 mgDO/l and $30^{\circ}C$, achieving 95% ammonia oxidization efficiency and nitrite ratio ($NO_2^-/{NO_x}^-$) of 0.95. High DO (5-6 mg/l) and low temperature ($20^{\circ}C$) had negative impacts on nitrite accumulation, leading to nitrite ratio drop to 0.6. However, the nitrite ratio achieved in the bioaugmented MBR was higher than that in most previous literatures. Denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization (FISH) were used to provide an insight into the microbial community. It showed that Nitrosomonas-like species as the only detected AOB remained predominant in the bioaugmented MBR all the time, and coexisted with numerous heterotrophic bacteria. The heterotrophic bacteria responsible for mineralizing soluble microbial products (SMP) produced by nitrifiers belonged to the Cytophaga-Flavobacterium-Bacteroides (CFB) group, and $\alpha$-, $\beta$-, and $\gamma$- Proteobacteria. The fraction of AOB ranging from 77% to 54% was much higher than that of nitrite-oxidizing bacteria (0.4-0.9%), which might be the primary cause for the high and stable nitrite accumulation in the bioaugmented MBR.

Assessment of Viral Attenuation in Soil Using Probabilistic Quantitative Model (확률적 정량모델을 이용한 토양에서의 바이러스 저감 평가)

  • Park, Jeong-Ann;Kim, Jae-Hyun;Lee, In;Kim, Song-Bae
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.7
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    • pp.544-551
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    • 2011
  • The objective of this study was to analyze VIRULO model, a probabilistic quantitative model, which had been developed by US Environmental Protection Agency. The model could assess the viral attenuation capacity of soil as hydrogeologic barrier using Monte Carlo simulation. The governing equations used in the model were composed of unsaturated flow equations and viral transport equations. Among the model parameters, those related to water flow for 11 soil types were from UNDODA data, and those related to 5 virus species were from the literatures. The model compared the attenuation factor with threshold of attenuation to determine the probability of failure and presented the exceedances and Monte Carlo runs as output. The analysis indicated that among 11 USDA soil types, the viral attenuation capacity of loamy sand and sand were far lower than those of clay and silt soils. Also, there were differences in the attenuation in soil among 5 viruses with poliovirus showing the highest attenuation. The viral attenuation capacity of soil decreased sharply with increasing soil water content and increased nonlinearly with increasing soil barrier length. This study indicates that VIRULO model could be considered as a useful screening tool for viral risk assessment in subsurface environment.