• Title/Summary/Keyword: Center Loss

Search Result 3,753, Processing Time 0.029 seconds

Study of the cumulative dental caries rate of pit and fissure sealant in community public health program: 3 years follow-up (3년간 추적연구에 의한 지역사회 치면열구전색사업의 누적치아우식발생률에 관한 연구)

  • Jeon, Mae-Sook;Kim, Chang-Suk;Lee, Kyeong-Soo
    • Journal of Korean society of Dental Hygiene
    • /
    • v.16 no.1
    • /
    • pp.45-52
    • /
    • 2016
  • Objectives: The purpose of the study was to investigate the cumulative dental caries rate of pit and fissure sealant in community public health program from 2005 to 2008 follow-up. Methods: The subjects were 4,768 students of 34 elementary schools in Gimcheon. The survey included direct oral examination and cumulative retention rate of pit and fissure sealant from 2005 to 2008. Data were analyzed using PASW statistical package version 18.0 and the level of significance was set at p<0.05. Results: The cumulative retention rate of sealant was 18%, 25%, and 33% after 1 year, 2 years, and 3 years, respectively. In addition, the cumulative retention rate of lower teeth was higher than that of upper teeth. Cumulative dental caries rate increased in sealed group and no sealed group. The cumulative dental caries rate decreased owing to tooth brushing frequency in sealed group and no sealed group. Conclusions: Regular and timely tooth brushing can maintain good oral health condition after tooth sealing. The school based oral health education can prevent loss of sealant and secondary caries.

Characteristics of Combustion Radical in CNG Direct Injection Vessel (CNG 직접분사식 연소기에서의 연소 라디칼 특성)

  • 최승환;조승완;이석영;정동수;전충환;장영준
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.12 no.5
    • /
    • pp.58-65
    • /
    • 2004
  • A cylindrical constant volume combustion chamber was used to investigate the combustion characteristics of stratified methane-air mixture under several initial charge conditions in the author's previous reports. The results showed that the improvement of thermal efficiency and reduction of heat loss was realized simultaneously by using 2-stage injection method. This paper deals with the reason why the stratified combustion has showed better combustion rate through the measurement and analysis of chemiluminescence of C $H^{*}$ and $C_{2}$$^{*}$ radicals. An optic fiber bundle is used to measure the local emission of C $H^{*}$ and $C_{2}$$^{*}$ radicals to map the relationship between the excess air ratio and local radical intensity ratio in the combustion vessel at 5 mm apart form the geometric center. The results show that there exist a relationship between the intensity ratio and the air-fuel ratio. It is revealed that the improvement of combustion rate in a lean-stratified mixture is realized through the 2-stage injection method. method.

Optimization of the Parallel Diesel Hybrid Vehicle (병렬형 디젤 하이브리드 전기 자동차 최적화)

  • Yeom, Ki-Tae;Yang, Jae-Sik;Bae, Choong-Sik;Kim, Hyun-Ok
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.16 no.6
    • /
    • pp.26-32
    • /
    • 2008
  • This research presents a simulation for the fuel economy of parallel diesel hybrid vehicle. Diesel engines compared to gasoline engines have the advantages of higher fuel economy and lower $CO_2$ emission. One of the most ways to meet future fuel economy and emissions regulation is to combine diesel engine technology with a hybrid electric vehicle. The simulation of HEV is growing need for rapid analysis of the many configurations and component options. WAVE, a one-dimensional engine analysis tool, was used to a 2.7L diesel engine. ADVISOR, designed for rapid analysis of the performance and fuel economy of vehicle models, was used to conventional and hybrid electric vehicle by the use of output file from WAVE as the input engine data file for ADVISOR. A parallel diesel HEV is at least $19.7{\sim}36%$ higher fuel economy and improved acceleration ability compared to a conventional diesel vehicle. The energy loss of the parallel diesel HEV is $23{\sim}38%$ less than the conventional vehicle using regeneration.

Effect of Ethylene Removal on Fruit Quality of Oriental Pear during Storage (저장고 내의 에틸렌 제거가 배 과실의 품질에 미치는 영향)

  • Kim Ho-Cheol;Bae Kang-Soon;Bae Jong-Hyang;Jeon Kyung-Soo;Hong Jong-Uk
    • Journal of Bio-Environment Control
    • /
    • v.15 no.1
    • /
    • pp.78-83
    • /
    • 2006
  • The objective of this study was to examine effect of ethylene removal apparatus on fruit quality of 'Niitaka' pear (Pyrus pyrifolia) in case of a double storage of apples and pears in a storage room. Ethylene and carbon dioxide concentration were efficiently decreased by the ethylene removal apparatus. Fruit weight loss was high at double storage of apples and pears (DAP) in a storage room compared with storage of pears. Fruit core browning was $5{\sim}22.5%$ at the fruits in DAP, but as setting ethylene removal apparatus it was not occurred till 90 days after storage. Soluble solids content and fruit peel hardness were not different among the treatments. Accordingly, a double storage of apples and pears in a storage room is possible as setting ethylene removal apparatus.

Heat Transfer Correlation to Predict the Evaporation of a Water Droplet in Superheated Steam during Reflood Phase of a LOCA

  • Kim, Yoo;Ban, Chang-Hwan
    • Journal of Energy Engineering
    • /
    • v.9 no.3
    • /
    • pp.261-268
    • /
    • 2000
  • A heat transfer correlation to predict the vaporization of a water droplet in highly superheated steam during a loss-of-coolant accident(LOCA) of a nuclear power plant is provided. Vaporization of liquid fuel or water droplets in superheated air or steam and subsequent interface heat transfer between a liquid droplet and superheated gas is typically correlated by way of a Nusselt number as a function of Reynolds number, Prantl number, and in some cases including mass transfer number. Presently available correlations and experimental data of the evaporation of liquid droplets in air or steam are analyzed and a new Nusselt number correlation is proposed taking Schmidt number into consideration in order to account for binary diffusion of the vapor as well, Nu$\_$f/(1+B)$\^$0.7/=2+0.53Sc$\_$f/$\^$-1/5/Re$\_$M/$\^$$\sfrac{1}{2}$/Pr$\_$f/$\^$$\sfrac{1}{3}$/ for which properties are evaluated at film condition except the density of Reynolds number evaluated at ambient condition. Diverse correlations for various combinations of liquid and gas species are put into single equation. The blowing correction factor of (1+B)$\^$0.7/ is confirmed appropriate, and a criterion to distinguish so-called high- and low-temperature condition of ambient gas is set forth.

  • PDF

Plagiarism Detection among Source Codes using Adaptive Methods

  • Lee, Yun-Jung;Lim, Jin-Su;Ji, Jeong-Hoon;Cho, Hwaun-Gue;Woo, Gyun
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.6 no.6
    • /
    • pp.1627-1648
    • /
    • 2012
  • We propose an adaptive method for detecting plagiarized pairs from a large set of source code. This method is adaptive in that it uses an adaptive algorithm and it provides an adaptive threshold for determining plagiarism. Conventional algorithms are based on greedy string tiling or on local alignments of two code strings. However, most of them are not adaptive; they do not consider the characteristics of the program set, thereby causing a problem for a program set in which all the programs are inherently similar. We propose adaptive local alignment-a variant of local alignment that uses an adaptive similarity matrix. Each entry of this matrix is the logarithm of the probabilities of the keywords based on their frequency in a given program set. We also propose an adaptive threshold based on the local outlier factor (LOF), which represents the likelihood of an entity being an outlier. Experimental results indicate that our method is more sensitive than JPlag, which uses greedy string tiling for detecting plagiarism-suspected code pairs. Further, the adaptive threshold based on the LOF is shown to be effective, and the detection performance shows high sensitivity with negligible loss of specificity, compared with that using a fixed threshold.

Isolation of Glucose Isomerase Hyperproducing Strain, Streptomyces sp. SM 805 and Its Enzymatic Properties

  • Kim, Hong-Rip
    • Journal of Microbiology and Biotechnology
    • /
    • v.2 no.2
    • /
    • pp.78-84
    • /
    • 1992
  • Streptomyces sp. No.8, which produced glucose isomerase was isolated from soil samples. The isolated strain, No.8, was identified as belonging to the Genus Streptomyces. A mutant strain, SM 805, showed the greatest ability to produce glucose isomerase. It was developed from the strain, No.8, by mutagenesis induced by NTG and UV treatment. The mutant strain, SM 805, produced about 7 times more glucose isomerase than the parental strain, No.8. This enzyme catalyzed the isomerization of D-xylose, D-glucose and D-ribose. It was inactive in the absence of metal ions, but was activated by the addition of $Mg^{2+}$ or $Co^{2+}$. The optimum temperature and pH for enzyme activity were $80^\circ{C}$ and pH 8.5, respectively. The enzyme was stable in a pH range of 6.0 to 10.0, and it was highly thermostable. There was no activity loss below $80^\circ{C}$, and even above $90^\circ{C}$ about 45% of its activity was retained. The reaction equilibrium was reached when about 53% fructose was present in the reaction mixture. Whole cells containing glucose isomerase from Streptomyces sp. SM 805 were immobilized by glutaraldehyde treatment. The resultant immobilized enzyme pellets showed a relatively long stability during the isomerizing reaction. The half-life of the immobilized enzyme during the operating was 45 days in the presence of 10mM $Mg^{2+}$.

  • PDF

In situ Hybridization of a Megalocytivirus Using Nucleic Acid Probes against ATPase and the Major Capsid Protein of Rock Bream Iridovirus

  • Lee, Nam-Sil;Do, Jeong-Wan;Jung, Sung-Ju;Park, Mi-Seon;Kim, Jin-Woo;Kim, Yi-Cheong
    • Fisheries and Aquatic Sciences
    • /
    • v.9 no.4
    • /
    • pp.146-152
    • /
    • 2006
  • Systemic infections of maricultured fishes by Megalocytivirus species have occurred over a broad area in South Korea, causing extensive economic loss. We developed digoxigenin-labeled nucleic acid probes against the 230-bp ATPase and 311-bp major capsid protein (MCP) of rock bream Oplegnathus fasciatus iridovirus (RBIV) using polymerase chain reaction, and an in situ hybridization (ISH) method to detect Megalocytivirus in formalin-fixed tissues of mariculture species (rock bream, sea bass, and olive flounder). ISH-positive cells were abundant in the hematopoietic and connective tissues of various organs, while brain tissue showed little or no signal. The ISH procedure can become an important diagnostic tool in complement with histopathological methods, and advances epidemiological studies on the origin and distribution of Megalocytivirus in mariculture.

Mandibular brown tumor in renal osteodystrophy

  • Park, Jin-Woo;Choi, Bo-Ram;Gang, Tae-In;Huh, Kyung-Hoe;Yi, Won-Jin;Choi, Soon-Chul
    • Imaging Science in Dentistry
    • /
    • v.38 no.4
    • /
    • pp.229-231
    • /
    • 2008
  • Brown tumor is a histologically benign lesion that is a serious complication of renal osteodystrophy because it may result in severe deformity and discomfort. We report a case of brown tumor, which occurred in a 35-year-old woman with chronic renal failure, who had been treated with hemodialysis for 14 years. The lesion was found on the lingual side of the mandible. Standard panoramic radiograph showed generally decreased bone mineral density, loss of lamina dura, and thin cortical plates. Computed tomography (CT) revealed multilocular expansile lesions with heterogeneous attenuation in the anterior mandible, as well as generalized trabecular alteration with homogeneous sclerosis, and thinning or obliteration of cortical plates. Excision of the mandibular lesion and curettage of the affected bone were performed. (Korean J Oral Maxillofac Radiol 2008; 38: 229-31)

  • PDF

Acute Back Pain Care after Mandibular Block Anesthesia in an Aged Woman with Multiple sclerosis -A Case Report- (다발성 경화증 노인환자에서 하악 전달마취 시행후 발생된 급성 요통치험 1예 -증례 보고-)

  • Lee, Chun-Ui;Mo, Dong-Yub;Yoo, Jae-Ha;Choi, Byung-Ho;Kim, Jong-Bae
    • Journal of The Korean Dental Society of Anesthesiology
    • /
    • v.10 no.2
    • /
    • pp.197-202
    • /
    • 2010
  • Multiple sclerosis is a degenerative disease prevalent in northern climates, and its cause is unknown. The histopathological lesion in multiple sclerosis is the sclerotic "plague", a discrete focus of myelin loss with maintenance of axon segments and glial proliferation. The plaques may be seen in widely different brain and spinal tissues. The common causes of low back pain are psychosomatic disorder, myofascial pain dysfunction syndrome and herniation of nucleus pulposus. Local anesthetics cross the blood-brain barrier and the signs of CNS toxicity appear at a level between 4.5 and $7.0\;{\mu}g/ml$. This is a case report of acute back pain care after mandibular block anesthesia for the surgical extraction of mandibular root rests in an old aged woman with multiple sclerosis.