• Journal of the Korean Society for Aviation and Aeronautics
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• v.24 no.2
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• pp.19-24
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• 2016

Positional stability analysis based on aerodynamic forces and induced moments of formation flight using two small aircraft models is presented. The aerodynamic force and moments of the trailing aircraft are analyzed in the aspect of flight stability. The induced moments with the change of local flow direction by wing-tip vortex from the leading aircraft can affect the flight positional stability of aircraft in closed formation flight. Aerodynamic forces and moments of trailing aircraft model are measured by 6-component internal balance at the 49 locations with vertical and lateral space between two aircraft models. Results are shown that the positional stability of trailing aircraft in formation flight can be analyzed by positional stability derivatives with vertical and lateral space. It is concluded that flying positions can be important factors for aircraft position stability due to induced aerodynamic force and moments with vertical and lateral spacing by the variation of flow pattern from the leading aircraft in formation flight.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.4
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• pp.321-327
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• 2012

This paper presents a comparative analysis on three different types of performance indices of obstacle detection for an overlapped ultrasonic sensor ring. Due to beam overlap, the entire sensing zone of each ultrasonic sensor can be divided into three smaller sensing subzones, which leads to significant reduction of positional uncertainty in obstacle detection. First, the positional uncertainty in obstacle detection is expressed in terms of the area of a sensing subzone, and type 1 performance index is then defined as the area ratio of side and center sensing subzones. Second, based on the area of a sensing subzone, type 2 performance index is defined taking into account the size of the entire range of obstacle detection as well as the degree of the positional uncertainty in obstacle detection. Third, the positional uncertainty in obstacle detection is now expressed in terms of the length of the uncertainty arc spanning a sensing subzone, and type 3 performance index is then defined as the average value of the uncertainty arc lengths over the entire range of obstacle detection. Fourth, using a commercial low directivity ultrasonic sensor, the changes of three different performance indices depending on the parameter of an overlapped ultrasonic sensor ring are examined and compared.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.1
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• pp.35-38
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• 2015

Lateral canal benign paroxysmal vertigo (BPPV) causing dizziness is a common cause is not found while continuing to appeal for vertigo is a typical disease. It is characterized by acute stand up, brief and rotatory vertigo attacks provoked by change in head position. Treatment requires only one treatment visit in most patients. However, there are significant numbers of patients who require multiple treatment visits for relief. The purpose of this study benign paroxysmal positional vertigo treatment of type affect is to analyze the cause. Dizziness and vertigo patient's in patients admitted to the dizziness center of lateral canal benign paroxysmal positional vertigo were classified. In patients with lateral canal benign paroxysmal positional vertigo and accompanying lateral 15 treatment affects disease were investigated. March 2008 to November 2010 lateral canal benign paroxysmal positional vertigo 166 people cure rate of patients was investigated. First time the success rate of 74.1%, twice times the success rate of 12.0%, three times the success rate of 9.6%, more than three times the success rate was 4.2%. Affecting factor treatment of benign paroxysmal positional vertigo in post-traumatic, medicine disease, headache, cerebral infarction, small vessel disease, vestibulopathy, (p<0.05). Statistical analysis using SPSS (version 12K) in coefficient measure through descriptive statistical of cross table.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.363-366
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• 2007

Road Design is being reached to the working design to produce drawings, calculate construction quantity and cost, through the basic design that contained feasibility study and all impact assessment. In general, to plan the route we use topographic map. The vertical positional accuracy is 30cm and horizontal positional accuracy is 35cm in 1:1,000 scale topographic map. In LiDAR, vertical positional accuracy is 15cm and horizontal positional accuracy is 30cm. So if we use LiDAR on road design, more accurate earth-volumn will be calculated when we plan the route. In this paper we try to find the method to use the LiDAR data on road design by drawing the profile and cross sectional view and comparing the earth-volumn to the road that working design is in process adopting the topographic map and LiDAR data.

• The korean journal of orthodontics
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• v.23 no.1 s.40
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• pp.101-113
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• 1993

For the purpose of interpretation of positional changes of craniofacial structures in Class III malocclusion between mixed and permanent dentition, 73 normal samples and 103 Class III samples of mixed dentition and 125 normal samples and 168 Class III samples of permanent dentition were selected. Comparative cephalometric analysis was undertaken between them respectively by mesh diagram method to evaluate the positional changes of maxilla and mandible in anteroposterior direction and vertical direction and also the inclination changes of maxillary and mandibular incisors in labio-lingual direction. The following results were obtained : 1. The antero-posterior positional changes of the maxilla and mandible were posterior direction of maxilla and anterior direction of mandible. 2. The vertical positional changes of the maxilla and mandible were superior direction of both maxilla and mandible. 3. The labio-lingual inclination changes of the maxillary and mandibular incisors were lingual direction of both maxillary and mandibular incisors.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.5 no.1
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• pp.1-9
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• 2010

Objectives: The purpose of this study is to evaluate the therapeutic effect of Positional Release Therapy on patients of neck pain, Methods: 12 patients was treated by Positional Release Therapy(PRT) combined with acupuncture, We measured the Visual Analog Scale(VAS) and Neck Disability Index(NDI) before and after treatment The statistical analysis was performed by using the Wilcoxon signed rank test. Results: 1. Patients showed significant improvement in VAS after treatrnent(p<0.05). 2. Patients showed significant improvement in NDI after treatment(p<0.05). Conclusion: These results imply that Positional Release Therapy combined with acupuncture would be effective on relieving pain and increasing functional ability in daily-life of patients of neck pain.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.1
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• pp.79-88
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• 2014

Enhancing the working speed and positional accuracy of high-speed press machines is essential for improving the parts accuracy and productivity. However it is known that the positional accuracy decreases and the risk of parts failure increases as the working speed of press machine increases. Therefore predicting such problems during the stage of press structure design is necessary for precise design of high-speed press machines. In the present investigation, the dynamic-elastic deformation of press drive module parts with eccentric masses was examined by finite element analysis and experiment. Then the positional accuracy and parts failure of high-speed press machines was evaluated.

• The Journal of Internal Korean Medicine
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• v.32 no.3
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• pp.371-386
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• 2011

Background : Vertigo is a very common complaint in clinical practice. The number of patients who complain of vertigo has been increasing due to rapid growth of the elderly population. This study was designed to review the clinical features and success of oriental medical treatment of positional vertigo. Methods : This observation was made on 70 subjects diagnosed with positional vertigo. They were hospitalized in the Semyung University Oriental Medicine Hospital. Results : The results were as follows 1. Female patients (82.9%) were more than male patients. The most common age group was 8th decade and the patients rapidly increased after the 5th decade of age. 2. The most common past history of positional vertigo was hypertension, the second was cerebral infarction, and the third was hyperlipidemia. 3. In the oriental medicine diagnosis, phlegm-dampness syndrome (痰濕交阻 眩暈) was the most common disease (92.9%), and in western medicine, BPPV was the most (82.9%). 4. In herbal medication, Banhabaekchulchunma-tang gami (45.7%) was the most commonly used, the second being Taeksa-tang (30%). 5. The vertigo score of 94.3% patients improved and none got worse. 6. In general characteristics, men over 64 years improved best. Past history had no effect on the improvement of vertigo. 7. The sooner patients visited hospital after onset, the shorter hospitalization time was. Conclusions : Vertigo attacks patients well in advanced age, with various causative diseases. Oriental medical treatments have considerable effects on positional vertigo, especially treated with Banhabaekchulchunma-tang gami and Taeksa-tang.

• Korean Journal of Clinical Laboratory Science
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• v.40 no.1
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• pp.62-70
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• 2008

Benign paroxysmal positional vertigo (BPPV) is one of the most common clinical entities encountered in a dizzness clinic. Retrosepective review was performed for the patient's diagnosed as BPPV at Sunchon "S" hospital dizzness center. Variables for statistical analysis included age, sex, involved canal presence of recent head tramua, presence of chronic otitis media, history of middle ear surgery, underlying disease such as hypertension or diabetics, headache, central lesion. From July 2004 to May 2005, we sampled the 600 dizzness patient's who visited the dizzness center. Dizzness could be classified into BPPV, vestibulopathy. Among these patients, 256 patients had BPPV, 222 patients had vesibulopathy and 97 patients had Normal. Among these BPPV patients, 80 patients had lateral canalolithiasis BPPV (31.3%), 28 patients had lateral cupulolithiasis BPPV (10.9%), 90 patients had posterior canalolithiasis BPPV (35.2%), 7 patients had multicanalolithiasis BPPV (2.3%), 52 patients simultaneously had BPPV, other vestibular disease, and central lesion (20.3%).

• Journal of Korean society of Dental Hygiene
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• v.18 no.1
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• pp.43-53
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• 2018

Objectives: The aims of this study were to analyze the job stress of clinical hygienists according to their positional system and to confirm its relevance. Methods: Seven hundred seventy six clinical dental hygienists participated in this survey. The questionnaire items consisted of general characteristics, working environment, and job stress. The data analysis was performed using IBM SPSS statistics ver.23.0 software. Results: Among the job stresses, the stress on the job demands was the highest with 63.4 points, and the stress on interpersonal conflict was the lowest with 34.6 points. The total score of job stress was the highest in the 26-30 year-old age group, and major stress factors in this group were job insecurity, organizational system, and lack of reward. Team members were more stressful about insufficient job control, organizational system, and lack of reward than team managers, while team managers were more likely to score interpersonal conflict. The dental hygienists in the hospitals that did not have the positional system got more stressed in the insufficient job control, organizational system, and lack of reward area. Conclusions: The presence of positional system was related to job demand, insufficient job control, organizational system, and lack of reward. Structural efforts such as establishing a proper positional system in dental clinics will be needed to control job stress in the clinical dental hygienists.