• Journal of Korean Neurosurgical Society
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• v.56 no.6
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• pp.475-481
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• 2014

Objective : To evaluate the anatomical feasibility of 3.5 mm screw into the cervical spine in the pediatric population and to establish useful guidelines for their placement. Methods : A total of 37 cervical spine computerized tomography scans (24 boys and 13 girls) were included in this study. All patients were younger than 10 years of age at the time of evaluation for the period of 2007-2011. Results : For the C1 screw placement, entry point height (EPH) was the most restrictive factor (47.3% patients were larger than 3.5 mm). All C2 lamina had a height larger than 3.5 mm and 68.8% (51/74) of C2 lamina had a width thicker than 3.5 mm. For C2 pedicle width, 55.4% (41/74) of cases were larger than 3.5 mm, while 58.1% (43/74) of pedicle heights were larger than 3.5 mm. For pedicle width of subaxial spine, 75.7% (C3), 73% (C4), 82.4% (C5), 89.2% (C6), and 98.1% (C7, 1/54) were greater than 3.5 mm. Mean lamina width of subaxial cervical spine was 3.1 (C3), 2.7 (C4), 2.9 (C5), 3.8 (C6), and 4.0 mm (C7), respectively. Only 34.6% (127/370) of subaxial (C3-7) lamina thickness were greater than 3.5 mm. Mean length of lateral mass for the lateral mass screw placement was 9.28 (C3), 9.08 (C4), 8.81 (C5), 8.98 (C6), and 10.38 mm (C7). Conclusion : C1 lateral mass fixation could be limited by the morphometrics of lateral mass height. C2 translamina approach is preferable to C2 pedicle screw fixation. In subaxial spines, pedicle screw placement was preferable to trans-lamina screw placement, except at C7.

• Proceedings of the KACD Conference
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• 2001.11a
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• pp.553-553
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• 2001

The purpose of this study is to identificate root canal system including ideal access placement, root curvature, canal configuration, incidence of isthmus in mandibular incisors for success of endodontic treatment. 200 mandibular incisors were selected. The ideal access placement was determimed as follows. The teeth were radiographed from mesiodistal and buccolingual views using intraoral dental film. The image was divided into coronal, middle and apical third using the proximal film. Straight line access was determined by measuring the faciolingual canal width and placing points at midway point between the buccal and lingual wall at the junction of the middle and apical third and at the juntion of coronal and middle third of the root canal.(omitted)

• Proceedings of the KACD Conference
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• 2001.11a
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• pp.562.2-562
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• 2001

The purpose of this study is to identificate root canal system including ideal access placement, root curvature, canal configuration, incidence of isthmus in mandibular incisors for success of endodontic treatment. 200 mandibular incisors were selected. The ideal access placement was determined as follows. The teeth were radiographed from mesiodistal and buccolingual views using intraoral dental film. The image was divided into coronal, middle and apical third using the proximal film. Straight line access was determined by measuring the faciolingual canal width and placing points at midway point between the buccal and lingual wall at the junction of the middle and apical third and at the juntion of coronal and middle third of the root canal.(omitted)

• JSTS:Journal of Semiconductor Technology and Science
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• v.6 no.4
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• pp.234-239
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• 2006

In the past decade, several tools have been developed to automate the floating-point to fixed-point conversion for DSP systems. In the conversion process, a number of scaling shifts are introduced, and they inevitably alter the original code sequence. Recently, we have observed that a compiler can often be adversely affected by this alteration, and consequently fails to generate efficient machine code for its target processor. In this paper, we present an optimization technique that safely migrates scaling shifts to other places within the code so that the compiler can produce better-quality code. We consider our technique to be safe in that it does not introduce new overflows, yet preserving the original SQNR. The experiments on a commercial fixed-point DSP processor exhibit that our technique is effective enough to achieve tangible improvement on code size and speed for a set of benchmarks.

• The KIPS Transactions:PartA
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• v.11A no.4
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• pp.267-276
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• 2004

The modeling methods of routing region used in the automatic placement/routing system are a grid and non-grid. Because the gird method is curbed by its size and a board if the electrical and physical elements on PCB are of small quantity, it has many memories. Therefore, it has demerit which decreases the speed of automatic placement/routing. The Shape-based type, non-grid method, makes the shapes exist as an in dividual element in a memory by using a region-processing method. Each individual element needs very small memory since it has its unique data size. Therefore, this paper aimed to develope the automatic placement/routing system which can automatically place and route the PCB without dissipation of memory at a high speed. To this aim, the auction algorithm method was applied which can make the memories be most rapidly reached from the original point to various destinations. Also, this system was developed by the Visual C++ in the Widows environment of IBM Pentium computer in order to use it in an individual PC system.

• International Journal of Highway Engineering
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• v.12 no.1
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• pp.39-46
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• 2010

Delineator is a useful device to support driver's safer maneuver. Effective placement and operation of the delineator would lead to prevent traffic accidents on the roads. This study evaluates the effectiveness of parameters associated with delineator placement and operation, which include spacing, height and size, from the point of user's satisfaction. Also, this study devises a methodology for determining such parameters using binary logistic regression technique. The proposed model is capable of producing probabilistic measure of user's satisfaction according to the various parameters. The outcome of this study would be useful fundamentals for more effective placement and operation of delineators.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.3
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• pp.484-490
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• 2016

Full-duplex communication can enhance wireless capacity by enabling simultaneous transmission and reception of the signals on the same frequency spectrum. Such a benefit, however, is only achieved when strong self-interference is well canceled below a sufficient level. To achieve this goal, there have been several approaches for cancellation, each of which is combined with digital-domain cancellation for a higher gain. In this paper, we implement two self-interference cancellation techniques and integrate them with a software defined radio-based wireless communication testbed. Two cancellation techniques (antenna cancellation and noise subtraction) are implemented and the cancellation gain is measured via real experiments. The results show that the gain of the antenna placement technique highly depends on the placement of a receiving antenna and the highest gain is achieved at the expected point, and we show that combining the noise subtraction circuit with the antenna placement further improves the cancellation gain.

• Journal of Digital Contents Society
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• v.8 no.3
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• pp.263-267
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• 2007

From our analysis of pedestrian walking behavior at the Daegeon underground shopping center, we think that the following changes might be necessary to improve sign placement and use. First, the discrepancy between the location of information signs and their rate of use should be reduced. Second, differences in information given by the signs that arise from problems with sign height and placement should be reduced. Third, signs should be distributed in such a way that they provide co-ordinated information about points and places. Fourth, the arrangement and placement of the signs should be considered from the view point of pedestrian walking behavior. Because there is difference in the number of installed signs and the rate of use of these signs, to increase the rate of information use it may be necessary to adjust the content and placement of the signs. Furthermore, analysis of subject walking paths shows that it is necessary for information to be offered about connections between spaces.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.26-37
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• 2009

This paper suggests a sensor's placement method for detecting the dilemma zone problem when real-time driver's safety service is provided at signalized intersections by multiple pointed traffic sensors using USN environments. For detecting the dangerous situations from vehicles accelerating through yellow intervals, red-light running and stopping abruptly like as dilemma zone problem, VISSIM(microscopic, behavior-based multi-purpose traffic simulation program) is used to perform a real-time multiple detection situation by changing the input data like as various inflow-volume, design speed change, driver perception and response time. As a result, the optimal interval of traffic sensors is 20~27m, and the initialized sensor location from stop-line is different according to road design speed. Moreover, the pattern of detection about dilemma zone is also different according to inflow-volumes. This paper shows that the method is useful to evaluate the sensor's placement problem based on micro-simulation and the results can be used as the basic research for USN services.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.314-316
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• 2001

This paper present the position control method for the application of permanent magnet linear synchronous motor. Controller is designed as a conventional P-PI controller, but the extra information is used such as velocity and acceleration from motion profiles. The profiles comes from S-Curve which is an optimized point-to-point motion profiles to achieve fast motions with minimum vibration[2]. In this application, the targets of the position control are maximum 10um position error within 10msec after respective ending point of position profiles. The implementation of the controller has been done in full digital way. All the controller is designed on the DSP TMS320VC33 control board. To prove performance of the controller, the experiment was performed with a servo linear motor.