• Journal of Sensor Science and Technology
• /
• v.22 no.2
• /
• pp.111-117
• /
• 2013

The autonomous driving method using magnetic sensors recognizes the position by measuring magnetic fields in autonomous robots or vehicles after installing magnetic markers in a moving path. The Position estimate method using magnetic sensors has an advantage of being affected less by variation of driving environment such as oil, water and dust due to the use of magnetic field. It also has the advantages that we can use the magnet as an indicator and there is no consideration for power and communication environment. In this paper, we propose an efficient sensor system for an autonomous driving vehicle supplemented for existing disadvantage. In order to efficiently eliminate geomagnetism, we analyze the components of the horizontal and vertical magnetic field. We propose an algorithm for position estimation and geomagnetic elimination to ease analysis, and also propose an initialization method for sensor applied in the vehicle. We measured and analyzed the developed system in various environments, and we verify the advantages of proposed methods.

• The Journal of Korea Robotics Society
• /
• v.2 no.3
• /
• pp.255-261
• /
• 2007

We propose a optimal fusion method for localization of multiple robots utilizing correlation between GPS on each robot in common workspace. Each mobile robot in group collects position data from each odometer and GPS receiver and shares the position data with other robots. Then each robot utilizes position data of other robot for obtaining more precise estimation of own position. Because GPS data errors in common workspace have a close correlation, they contribute to improve localization accuracy of all robots in group. In this paper, we simulate proposed optimal fusion method of odometer and GPS through virtual robots and position data.

• Design & Manufacturing
• /
• v.14 no.4
• /
• pp.40-45
• /
• 2020

In a vehicle-to-vehicle accident, the impact posture, braking status, final stopping position, collision point and collision speed are important factors for accident reconstruction. In particular, the speed of collision is the most important issue. In this study, the collision speed and the final stopping position in the tunnel were estimated using PC-CRASH, a vehicle crash analysis program used for traffic accident analysis, and the final stopping position of the simulation and the final stopping position of the traffic accident report were compared. When the Pride speed was 0km/h or 30km/h and the Sorento speed was 100m/h, the simulation results and reports matched the final stopping positions and posture of the two vehicles. As a result of the simulation, it can be estimated that Pride was collided in an almost stationary state.

• The Journal of Korean Physical Therapy
• /
• v.22 no.6
• /
• pp.29-33
• /
• 2010

Purpose: This study was designed to investigate inter-rater and intra-rater reliability of navicular drop measurements by clinicians in sitting and standing positions. Methods: Fourteen subjects with pronated foot were recruited. Two physical therapists randomly assessed the same patients on different occasions but on the same day. Almost all patients were assessed on more than one day. The intra-rater and inter-rater reliability of navicular dropwas estimated by calculation of the intraclass correlation coefficient (ICC). Results: The intra-rater reliability of navicular drop measurements ranged from 0.93 to 0.87, the inter-rater reliability from 0.98 to 0.70 with the patient in standing and sitting positions. These results showed good reliability for calculated variables. Intra-rater and inter-rater reliability of navicular drop in standing position was higher than those of sitting position. Conclusion: Although inter-rater and intra-rater reliability of navicular drop in the sitting position was lower than in the standing position, measurement of navicular drop in the sitting position showed good reliability and was acceptable for patients who could not stand alone without assistance. We recommend that having the patient in the standing position is appropriate in navicular drop measurement.

• Journal of Mechanical Science and Technology
• /
• v.17 no.8
• /
• pp.1140-1147
• /
• 2003

We have examined the effect on neck-muscle activation of altering whole body posture. A Rhesus monkey (Macaca mulatta) was trained to produce sinusoidal (0.25 Hz) head tracking movements in the sagittal plane when seated with trunk and head vertical or while standing in the quadrupedal position. Video-fluoroscopic images of cervical vertebral motion, and electromyographic (EMG) responses were recorded simultaneously. Results demonstrated that vertebral motion varied with body posture, occurring synchronously between all joints in the upright position and primarily at skull-$C_1$ when in the quadrupedal position. Muscle EMG activation was significantly greater (P<0.001) in the quadrupedal position than when upright for all muscles except semispinalis cervicis. Peak activation of all the muscles occurred prior to peak head extension in the quadrupedal position, suggesting synchronous activity between muscles. Data suggest that, when upright, muscles were activated in functional groupings defined by their anatomical arrangement. In the quadrupedal position, gravity acting on the horizontally oriented head produced greater activation and a collective response of the muscles.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.14 no.2
• /
• pp.83-93
• /
• 2019

Responding to the prior studies' call for further investigating the relationship between entrepreneurial orientation and firm performance, this study proposes a partially mediated model of entrepreneurial orientation, entrepreneurial knowledge position, and firm performance. Survey responses from 3,324 small- and medium-enterprises in South Korea are analyzed to identify a partially mediating role of an organization's entrepreneurial knowledge position. A firm's innovativeness both directly affects its innovation performance and knowledge position in positive ways. On the other hand, risk-taking firms only positively affects knowledge position, whereas a firm's proactiveness positively affects its performance while negatively affecting its entrepreneurial knowledge position. Neither autonomy nor competitiveness show any statistically significant relationships to either entrepreneurial knowledge position or firm performance. A firm's knowledge position is strongly and positively related to its performance. The findings of this study contributes to the research stream of entrepreneurial orientation by delineating the partially mediating role of a firm's knowledge position.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.26 no.2
• /
• pp.111-120
• /
• 2010

Purpose: This investigation was designed to evaluate the condyle position and the symmetry of the both condyle heads at the maximum intercuspal position on the sagittal CT image of the temporomandibular joint. Materials and Methods: Cone-beam CT was used to assess 400 joints in 100 symptom and 100 symtom-free subject(100 male, 100 female). Three independent observers(dentists) determined the positions classified with Anterior Position(AP), Middle Position(MP), and Posterior Position(PP), and the symmetry of the both condyle. Results: According to gender, the mean percentages of AP, MP, and PP were 48.5, 28.5, and 23 in male group, and 34, 38, and 28 in female group. The symmetry of condylar heads was more common than asymmetry in the both of groups. In the respect of symptom or symptom-free, the mean percentages of AP, MP, and PP were 44.5, 34, and 21.5 in the symptom-free group, and 37, 33.5, and 29.5 in the symptom group. The symmetry of condylar heads was more common in the symptom-free group, but the asymmetry of condylar heads was more common in the symptom group. Conclusions: These data might serve as useful criteria for the clinical assessment of condyle position at the maximum intercuspal position optained by Cone-beam CT.

• Journal of Biomedical Engineering Research
• /
• v.28 no.4
• /
• pp.494-502
• /
• 2007

Ubiquitous location based services (u-LBS) will be interested to an important services. They can easily recognize object position at anytime, anywhere. At present, many researchers are making a study of the position recognition and tracking. This paper consists of postion recognition and user identification system. The position recognition is based on location under services (LBS) using a signal strength map, a database is previously made use of empirical measured received signal strength indicator (RSSI). The user identification system automatically controls instruments which is located in home. Moreover users are able to measures body signal freely. We implemented the multi-hop routing method using the Star-Mesh networks. Also, we use the sensor devices which are satisfied with the IEEE 802.15.4 specification. The used devices are the Nano-24 modules in Octacomm Co. Ltd. A RSSI is very important factor in position recognition analysis. It makes use of the way that decides position recognition and user identification in narrow indoor space. In experiments, we can analyze properties of the RSSI, draw the parameter about position recognition. The experimental result is that RSSI value is attenuated according to increasing distances. It also derives property of the radio frequency (RF) signal. Moreover, we express the monitoring program using the Microsoft C#. Finally, the proposed methods are expected to protect a sudden death and an accident in home.

• Korea Journal of Hospital Management
• /
• v.6 no.3
• /
• pp.46-68
• /
• 2001

The study was to examine the relationships among those variables related to total quality management and to reveal those variables affecting total quality management in Health-Care Organizations. To study the relationship, a questionaire was designed and sent to 220 hospitals of which the number of beds is over 200 beds. Out of 660 questionaire, 263 questionaire were collected. Data analysis were conducted by using t-test, ANOVA, Pearson correlation coefficients and stepwise multiple regression. The result were as follows: 1. TQM was significantly different according to activities of QI, department of QI, age, and position. 2. Leadership was significantly different according to activities of QI, department of QI, age, and position. 3. Significant differences in the level of satisfaction of employee were found according to activities of QI, department of QI, age, position, and duration of employ. 4. Significant differences in the level of participation of employee were found according to activities of QI, department of QI, and position. 5. Education trainning was significantly different according to amount of bed, activities of QI, department of QI, level of education, kind of job, and position. 6. Medical technique was significantly different according to activities of QI, department of QI, and position. 7. Quality of work was significantly different according to activities of QI, department of QI, age, and position. 8. Significant differences in the level of investigation's system in satisfaction of client were found according to activities of QI, department of QI, kind of job, and position. 9. Positive correlations were observed between TQM and those variables related to TQM. 10. TQM was significantly predicted by the level of satisfaction of employee(40.9%), participation of employee(7.0%), investigation's system in satisfaction of client(2.7%), leadership(1.4%), and medical technique(1.1%), respectively.

• Journal of Korean Neurosurgical Society
• /
• v.63 no.4
• /
• pp.504-512
• /
• 2020

Objective : An important factor during pituitary adenoma surgery is to preserve pituitary stalk (PS) as this plays a role in reduction of the risk of postoperative diabetes insipidus. The hypothalamic-hypophyseal tract (HHT) projects through the PS to the posterior pituitary gland. To reconstruct white matter fiber pathways, methods like diffusion tensor imaging (DTI) tractography have been widely used. In this report we attempted to predict the position of PS using DTI tractography and to assess its intraoperative correlation during surgery of pituitary adenomas. Methods : DTI tractography was used to tract the HHT in nine patients before craniotomy for pituitary adenomas. The DTI location of the HHT was compared with the PS position identified at the time of surgery. DTI fiber tracking was carried out in nine patients prior to the planned craniotomy for pituitary adenomas. In one patient, the PS could not be identified during the surgery. In the other eight patients, a comparison was made between the location of the HHT identified by DTI and the position of the PS visualized at the time of surgery. Results : The position of the HHT identified by DTI showed consistency with the intraoperative position of the PS in seven patients (88.9% concordance). Conclusion : This study shows that DTI can identify the position of the HHT and thus the position of the PS with a high degree of reliability.