• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.858-861
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• 2004

This paper presents a wavelet-based neural network technology for the detection and classification of the various types of power quality disturbances. Power quality phenomena are short-time problems and of many varieties. Particularly, the transients happen during very short durations to the nano- and microsecond. Thus, a method for detecting and classifying transient signals at the same time and in an automatic combines the properties of the wavelet transform and the advantages of neural networks. Especially, the additional feature extraction to improve the recognition rate is considered. The configuration of the hardware of WN (PQ-DAS) and some case studies are described.

• Clinical and Experimental Pediatrics
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• 제50권8호
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• pp.718-725
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• 2007

Sleep disorders are very common among pediatric patients. Its prevalence is between 10% and 45% in preschool- and school-aged children. However parents commonly do not concern about their children's sleeping habits and for many pediatricians, there is not part of the routine office visit about a childs sleep. Sleep disorders were classified by International Classification of Sleep Disorder (ICSD) as dyssomnias, parasomnias, sleep disorders associated with mental, neurologic, or other medical disorders, and proposed sleep disorders. There are lots of differences in the causes, manifestations, and managements of sleep disorders between children and adult. The sleep disorders in childhood may manifest themselves as bedtime resistance, refusal to go to bed at a parentally described time, sleep-onset delay, inability to fall asleep within a reasonable time, prolonged nighttime awakening, and inability to return to sleep without assistance after waking during the night, and so have wide-ranging influences on children's behavior, mood, school performance, and family life. It's very important for pediatrician to concern about the sleep disturbances in childhood and so the problems of sleep in children should be early detected and managed.

• 한국군사과학기술학회지
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• 제10권2호
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• pp.12-20
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• 2007

The aiming ability is a key to improve the accuracy performance of the gun pointing system in the ground military vehicle. This paper describes the new detection method of chatter vibration using disturbance acceleration in the pointing structure. In order to analysis the vibration trends of the pointing system occurred while the vehicle driving, acceleration data obtained from vehicle was processed by using data processing algorithm with moving average and Hilbert transform. The specific mode constants of acceleration were obtained from various disturbances. Vehicle velocity, road condition and property of pointing structure were considered as factors which make the change of vibration trend in vehicle dynamics. Finally, back propagation neural networks have been applied to the pattern recognition of the classification of vibration signal in various driving conditions. Results of signal processing were compared with other condition result and analysed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.397-399
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• 1994

In this paper a feature-based automatic neural network signal classifier is presented, where five neural network algorithms such as MLP, RBF, LVQ2, MLP-Tree and LVQ-Tree are combined in parallel to classifiy various signals from their features, based on the majority vote method. To demonstrate the performance and applicability of the proposed signal classifier, some test results for the classification of synthetic waveforms and power disturbances are provided.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.202-204
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• 2004

This paper presents a neural network technology for the detection and classification of the various types of power quality disturbances. Power quality phenomena are short-time problems and of many varieties. Particularly, the transients happen during very short durations to the nano- and microsecond. Thus, a method for detecting ·md classifying transient signals at the same time and in an automatic combines the properties of the wavelet transform and the advantages of neural networks. We test two neural network and compare the results of Backpropagation Neural (BPN) network with Radial basis function network (RBFN). RBFN is more useful to detect and classify than BPN. The configuration of the hardware of PQ-DAS and some case studies are described.

• Journal of Periodontal and Implant Science
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• 제49권2호
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• pp.127-135
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• 2019

Purpose: The aim of this study was to evaluate the computed tomography (CT) imaging findings and clinical symptoms of patients who complained of neurosensory disturbances after mandibular implant surgery, and to investigate the relationships of these parameters with the prognosis for recovery. Methods: CT scans were reviewed in 56 patients with nerve disturbance after mandibular implant surgery. Two oral radiologists classified the imaging findings into intrusion, contact, close, and separate groups according to the distance from the inferior border of the implant to the roof of the mandibular canal (MC). The symptoms of 56 patients were classified into 8 groups and the frequency of each group was investigated. Patients were categorized according to symptom improvement into no recovery and recovery groups, and the relationships of recovery with the CT classification and specific symptom groups were analyzed. Results: Thirty-eight of the 56 nerve disturbance cases showed improvement. The close and separate groups in the CT classification had a strong tendency for recovery (90.9% and 81.8%, respectively) (P<0.05). Although the lowest recovery rate was found in the intrusion group, it was non-negligible, at 50%. The 6 patients with a worm crawling feeling all improved, while the 8 cases with a tightening sensation showed the lowest recovery rate, at 12.5%, and the symptom of a tightening sensation occurred only in the intrusion and contact groups. Conclusions: The closer the implant fixture was to the MC on CT images, the less likely the patient was to recover. Regarding paresthesia symptoms, while a worm crawling feeling is thought to be a predictor of recovery, a tightening sensation appeared to be associated with a lower recovery rate.

• 치과방사선
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• 제18권1호
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• pp.203-212
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• 1988

This study was designed to observe mandibular condyle shape and position in an asymptomatic popular ion. Using Accurad-200 head holder(Denar Corp.) for transcranial radiography of the temporo-mandibular joint region, transcranial radiographs were taken at the centric occlusion and 1 inch mouth opening in 73 males and females who were asymptomatic for TMJ disturbances, had no severe carious or missing teeth, and no history of prosthodontic or orthodontic treatments. Mandibular condyles were classified morphologically at the centric occlusion and evaluated in positional relationship with mandibular fossa and articular eminence at the centric occlusion and 1 inch mouth opening. The results were as follows: 1. In the morphologic classification of mandibular condyle, the convex shape was more prevalent in an asymptomatic population(90.4%), the locally concave shape and wedge shape were 5.5%, 4.1%. 2. At the centric occlusion, the means of joint space were 3.43nm superiorly, 2.17㎜ anteriorly, and 2.61㎜ posteriorly. 3. At the centric occlusion, the mandibular condyles were placed slightly anterior to the center of their fossa. 4. At the 1 inch mouth opening, the mandibular condyles were placed anterior to the articular eminence more than posterior to or below the top of the articular eminence.

• 한국추진공학회지
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• 제11권2호
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• pp.62-70
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• 2007

지향성능은 발사차량의 정확성에 있어서 중요한 요소이다. 본 연구는 외란 가속도를 이용하여 지향구조물의 진동을 감지하는 방안과 실험 결과에 대하여 기술하였다. 주행 중 발생하는 진동 경향을 분석하기 위하여 가속도 자료를 이동평균과 힐버트 변환을 이용하여 신호 처리하였다. 다양한 외란에 대하여 가속도의 모드 계수를 얻었으며, 차량속도, 노면조건, 지향구조물의 특성을 차량 동특성의 진동을 변화시키는 요소로 간주하였다. 마지막으로 다양한 주행 조건의 진동 신호를 분류하기 위한 패턴인식에 역전파 신경망 이론을 이용하였다. 각 조건에 대하여 실험 결과를 비교 분석하였다.

• 생물정신의학
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• 제13권3호
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• pp.170-177
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• 2006

Objectives : Disturbances of serotonergic system might be related to the possible mechanism of social phobia. This study was to investigate the association of serotonin transporter gene and social phobia. Methods : Sixty nine patients with social phobia(51 male(73.9%), mean age $35.17{\pm}11.89$ years) and seventy four normal controls(54 male(73.0%), mean age $33.46{\pm}9.63$ years) were tested for serotonin transporter gene-linked polymorphic region(5-HTTLPR) polymorphism. Additionally, patients were grouped into 46 generalized(GEN) and 23 nongeneralized(NGEN) subgroups and 5-HTTLPR polymorphism was compared with that of normal controls. The genotypes and allele frequencies of the 5-HTTLPR polymorphism between social phobia and the control group were compared. Genomic DNA was extracted from their blood and 5-HTTLPR polymorphisms were determined by using polymerase chain reaction. Results : Significant association was observed between the S(ss) genotype and social phobia, by functional classification(p=.010). In allele frequency analysis, a significant association was also observed between the short allele and social phobia(p=.030). A significant associations between S genotype and each subgroup were observed(GEN p=.045 ; NGEN p=.033), but there were no differences in allele frequency. And, no differences in genotype and allele distribution between two subgroups were found. Conclusion : The results in our Korean sample suggest that S genotype of 5-HTTLPR may be associated with social phobia and s allele may be an important genetic factor that activates social phobic symptoms. But, further studies including large number of samples are necessary to elucidate these present findings.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.1274-1279
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• 2005

The complex vegetation and plant species distributions within riparian corridors influence plant species diversity patterns at both local and regional scales and further reflect both natural and anthropogenic disturbances. Because of these characteristics, riparian zones are often the ecosystem level component that are most sensitive to changes of the surrounding environment; they provide early indications of environmental change and can be viewed as the important source in the watershed. The objectives of this study were two concepts: first, document the composition and dominance of plant communities of riparian areas in the stream, second, compare species composition and temporal diversity between stations in riparian areas of the Ian Stream. The flora was composed to total 158 kinds of the vascular plants as 49 family, 54 genera, 145 species, 12 varieties, 1 forma When the naturalized plant were applied to the recent classification system 280 kinds, the naturalization rate was $10.8\% higher than that of mean value($10.3\%$) of the Korean mountain district. Furthermore, urbanization index (UI) was $6.1\%$. The dominant vegetation communities were distributed in the habitats of three compartments from upstream to downstream. The vegetations were included Phragmites japonica, Salix gracilistyla, S. hulteni and Robinia pseudo-acacia in the riparian area, and Persicaria sieboldii, Stellaria alsine var. undulata, Draba nemorosa var. hebecarpa, Capsella bursa-pastoris, Lepidium apetalum, Bidens frondosa, Trigonotis peduncularis and Hemistepta lyrata in the sandbank or the riparian area, and Equisetum arvense, Humulus japonicus, Persicaria perfoliata, Trifolium repens, Artemisia princeps var. orientalis, Lactuca indica var. laciniata, Avena fatua, Agropyron yesoense, Oenothera odorata, Viola mandshurica, Rumex crispus in banksides, respectively.