• Restorative Dentistry and Endodontics
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• v.15 no.1
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• pp.175-186
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• 1990

The purpose of this study was to determine whether any clinical factors or conditions are associated with an increased incidence or degree of pain occuring during endodontic treatment in patients who begin treatment with no symptoms. The 260 teeth of 256 patients were surveyed and statistical analysis was used to determine whether a significant relationship existed between pain and any recorded clinical factors or conditions. The following conclusions were drawn. 1. No significant relationship between interappointment pain and any of the analyzed clinical factors or conditions except for fistula formation could be determined. 2. The presence of a draining fistula from a periapical lesion significantly decreased the posttreatment pain. 3. The judicious use of canal irrigants and canal medicaments is not associated with an increased incidence or degree of interappointment pain.

• Restorative Dentistry and Endodontics
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• v.16 no.1
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• pp.25-40
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• 1991

Four root canal sealers, Apatite Root Sealer I and II composed mainly of hydroxyapatite/tricalciumphosphate, Sealapex containing calcium hydroxide, and Roth Sealer composed of zinc oxide - eugenol were compared on the culture of L929 fibroblasts. MIT (Methyl Thiazole Tetrazolium Bromide) colorimetric technique was used to measure the mitochondrial dehydrogenase activity. Results were as follows: 1. Hydroxyapatite/tricalcium phosphate mixed sealers were significantly less toxic compared with calcium hydroxide and zinc oxide - eugenol type sealers. High pH of the calcium hydroxide sealer and release of eugenol component from the zinc oxide - eugenol type sealer were presumed to be the cause of the toxicity of these two sealers. In no cases, there were more cytoblastic effects in hydroxyapatite/tricalcium phosphate mixed sealers compared to the control groups. 2. In all experimental groups, toxicity was decreased as dilutions were increased. However in zinc oxide-eugenol type sealer the cell activity was weakened for all dilution groups. 3. Regarding the effect of setting time, Apatite I and Sealapex were less toxic as the setting progressed. Apatite II kept constant regardless of the different time ellapsed after setting but Roth sealer revealed significantly higher toxicity for all experimental groups. 4. Comparing two different culture periods of 24 hours and 72 hours, Apatite I showed higher cell activities in longer period(72 hours) while Apatite II did not. Sealapex and Roth sealer, however, showed significantly lower cell activities in longer period.

• Korean Journal of Ichthyology
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• v.25 no.2
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• pp.59-64
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• 2013

Two leptocephali (36.2~69.2 mm in total length) of the family Muraenidae were collected off Jeju Island, Korea. They were identified using 742 base pairs of mitochondrial DNA 12S rRNA sequences, and their morphological description were presented. The two leptocephali were identified to Gymnothorax minor based on genetic distance (d=0.000), being well consistent with that of G. minor adult collected off Tongyeong. Gymnothorax minor leptocephali are characterized by morphological combinations: total myomeres 137~139, predorsal myomeres 32, preanal myomeres 82~86, body depth in total length more than 10%.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07b
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• pp.301-303
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• 2005

최근 정보기술의 발전과 인터넷 서비스의 급속한 성장 둥으로 인하여 다양한 분야에서 웹 사이트가 운용중이며 품질의 중요성도 점차 인식되어지고 있다. 또한, 운용중인 웹 사이트 품질평가를 위해 적용할 품질모형 및 품질정가 프로세스는 평가대상 웹 사이트의 특성을 고려하여 선정이 요구된다. 따라서, 본 논문에서는 ISO/IEC 9126-4, WebQEM, 2QCV3Q, KNDU-SQEP를 적용하고, 미흡한 품질속성을 보완하기 위해 웹 사이트 품질평가를 위한 품질모형과 품질평가 프로세스를 제시하였다. 또한 웹 사이트 제품 평가 모델의 품질평가 점검표를 작성하여 포털 및 전문업무 사이트에 적용하고 WebQEM 모텔과 제안한 모델의 평가치를 비교하여 운용중인 웹 사이트에 대하여 평가가 가능한 것을 입증하였다. 향후에는 개발 중의 중간 산출물에 대한 품질평가 점검표의 개발을 통하여 전 수명주기에 대한 지원이 요구된다.

• Restorative Dentistry and Endodontics
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• v.29 no.3
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• pp.226-232
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• 2004

Use of electric pulp testing elicits painful response in vital teeth. In this study, we examined the excessive time from pain feeling to stimulation disconnection in clinical situation. D626D (Parkell Inc., USA.) scan type electric pulp tester was used in total of 23 young healthy individuals. Each of the right central incisors and first premolars were used as testing teeth. Stimulation disconnection was achieved by EMG in anterior belly of digastric muscle, finger span, and voice and the excessive stimulation time over the sensory thresh-old was recorded. As a result, we found that the short responses before the stimulation disconnection appeared following order：EMG, finger span, and voice. The EMG disconnection is suggested to be used to reduce the excessive stimulus time in electric pulp testing.

• Restorative Dentistry and Endodontics
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• v.37 no.2
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• pp.123-126
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• 2012

It is often presumed that apical periodontitis follows total pulp necrosis, and consequently root canal treatment is commonly performed. Periapical lesion development is usually caused by bacteria and its byproduct which irritate pulp, develop pulpitis, and result in necrosis through an irreversible process. Afterwards, apical periodontitis occurs. This phenomenon is observed as an apical radiolucency in radiographic view. However, this unusual case presents a spontaneous healing of periapical lesion, which has developed without pulp necrosis in a vital tooth, through conservative treatment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.590-597
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• 2022

We analyzed the diet composition of smallmouth argentine Argentina kagoshimae, which were collected via bottom trawl in the South Sea during February, April, August, and October 2021. Their size range was 8.1-21.4 cm total length. A. kagoshimae are mesopelagic carnivores, mainly consuming benthopelagic Euphausiacea and Caridea crustaceans. Polychaetes were the second largest prey component in their diet, which also included small quantities of copepods, amphipods, and arrow worms. Stomach content compositions substantially differed among body size levels in A. kagoshimae. The results of non-metric multidimensional scaling ordination and permutational multivariate analysis of variance of dietary data revealed no significant dietary differences. The results of a graphical analysis of the diet composition showed that A. kagoshimae are specialized feeders characterized by strong individual feeding specialization.

• Particle and aerosol research
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• v.18 no.4
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• pp.97-107
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• 2022

The geometry of popular wave plate type mist eliminator for the wet flue gas desulfurization process was improved, fabricated, and experimentally evaluated. A Mist eliminator is a type of inertial particle collector which collection efficiency is proportional to the velocity of the gas phase. However, as the amount of re-entrainment is also proportional to the gas phase velocity, there is a limitation for the gas phase flow rate. Re-entrainment is one of the most important issues in a mist eliminator and is likely to occur as the input of the liquid phase and flow rate of the gas phase increase. In order to resolve this problem, the projection angle of the improved mist eliminator is set to 30° from the conventional one while maintaining the cross-section. With low flow rate conditions, the modified mist eliminator showed a similar pressure drop and overall collection efficiency. However, with conditions in which re-entrainment is obviously occurring, the modified mist eliminator showed better performance in draining droplets than the conventional one. As a result, the modified mist eliminator showed higher overall collection efficiency.

• NICE (News & Information for Chemical Engineers)
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• v.31 no.1
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• pp.48-57
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• 2013

석탄가스화 기술은 석탄의 에너지원으로서의 중요성에 더하여 고효율 고청정 에너지화 기술이라는 측면에서 많은 기술선진국에서 시장 선점을 위하여 다양한 석탄가스화 기술을 개발하고 있다. 초기에는 미국과 유럽을 중심으로 기술개발이 이루어졌으나 최근에는 일본과 중국에서도 상업화 기술을 보유하는 수준에 이르렀다. 특히 중국은 우리나라보다 뒤늦게 기술개발을 시작하여 2000년 이전에만 하여도 석탄가스화 기술의 후진국이었으나 최근에는 ECUST와 TPRI 등이 주도적으로 기술개발을 진행하고 집중적인 연구개발 지원에 힘입어 이제 2,000톤/일급 이상의 가스화기 개발을 완료하고 수십기의 상업용 실적을 보유하는 등으로 비약적인 발전을 이루었다. 반면에 우리나라는 중국보다 이른 시점인 1990년대 초반부터 가스화 기술개발을 시작하여 많은 기술축적을 이루어 미분탄 기류 수송, 슬러리 제조, 탈황 기술 등의 일부 요소기술에서는 세계 수준급의 기술을 확보하고 있으나 연구비의 제한적인 투자로 인하여 규모의 측면에서는 아직 수톤~수십톤/일급 가스화기의 운전 또는 설계 진행 수준에 머무르고 있다. 우리나라의 경우 에너지의 대부분을 수입한다는 측면을 고려할 때에 저가의 에너지원 확보 및 에너지원의 다양성 확보 측면에서 석탄에너지 활용은 필수적이므로 석탄 활용 기술, 특히 석탄가스화 기술 개발에 많은 관심을 기울일 필요성이 아주 강하다고 판단된다.

• Journal of the Korean Society of Radiology
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• v.84 no.5
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• pp.1066-1079
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• 2023

Purpose Distinguishing intradural extramedullary (IDEM) spinal ependymoma from myxopapillary ependymoma is challenging due to the location of IDEM spinal ependymoma. This study aimed to investigate the utility of clinical and MR imaging features for differentiating between IDEM spinal and myxopapillary ependymomas. Materials and Methods We compared tumor size, longitudinal/axial location, enhancement degree/pattern, tumor margin, signal intensity (SI) of the tumor on T2-weighted images and T1-weighted image (T1WI), increased cerebrospinal fluid (CSF) SI caudal to the tumor on T1WI, and CSF dissemination of pathologically confirmed 12 IDEM spinal and 10 myxopapillary ependymomas. Furthermore, classification and regression tree (CART) was performed to identify the clinical and MR features for differentiating between IDEM spinal and myxopapillary ependymomas. Results Patients with IDEM spinal ependymomas were older than those with myxopapillary ependymomas (48 years vs. 29.5 years, p < 0.05). A high SI of the tumor on T1W1 was more frequently observed in IDEM spinal ependymomas than in myxopapillary ependymomas (p = 0.02). Conversely, myxopapillary ependymomas show CSF dissemination. Increased CSF SI caudal to the tumor on T1WI was observed more frequently in myxopapillary ependymomas than in IDEM spinal ependymomas (p < 0.05). Dissemination to the CSF space and increased CSF SI caudal to the tumor on T1WI were the most important variables in CART analysis. Conclusion Clinical and radiological variables may help differentiate between IDEM spinal and myxopapillary ependymomas.