• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.1
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• pp.34-40
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• 2012

Flux linkage of phase windings or phase inductance is an important parameter in determining the behavior of a switched reluctance motor (SRM) [1-8]. Therefore, the accurate prediction of inductance at aligned and unaligned rotor positions makes a significant contribution to the design of an SRM and its analytical approach is not straightforward due to nonlinear flux distribution. Although several different approaches using a finite element analysis (FEA) or curve-fitting tool have been employed to compute phase inductance [2-5], they are not suitable for a simple design procedure because the FEA necessitates a large amount of time in both modeling and solving with complexity for every motor design, and the curve-fitting requires the data of flux linkage from either an experimental test or an FEA simulation. In this paper, phase inductance at aligned and unaligned rotor positions is estimated by means of numerical method and magnetic equivalent circuit as well, and the proposed approach is analytically verified in terms of the accuracy of estimated inductance compared to inductance computed by an FEA simulation.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.2046-2047
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• 2007

This paper is about the energy efficiency calculation of operating electric motors in production facilities. The most important 1st step to efficient operation of plants is the evaluation of the energy efficiency of the production facilities in that plant. Through this procedure, we can decide that which facilities i.e. induction motors, in this paper, should do maintenance or not. There are mainly 2 types of energy which are used in production facilities, the one is electric energy and the other is heat energy but in order to make calculation simple, in this paper, we are only focusing on electric energy, efficiency and energy loss of the electric motors under operation conditions. As a case study, we chose electric motors in a certain process in a production facilities, and calculated efficiency and loss by using measured data.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.888-890
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• 2003

The objective of this investigation is to establish a simple yet effective block adjustment procedure for the orthorectification of multi-orbit satellite images. The major works of the proposed scheme are: (1) adjustment of satellite‘s orbit accurately, (2) calculation of the error vectors for each tie point using digital terrain model and ray tracing technique, (3) refining the orbit using the Least Squares Filtering technique and (4) generation of the orthophotos. In the process of least squares filtering, we use the residual vectors on ground control points and tie points to collocate the orbit. In orthorectification, we use the indirect method to generate the orthoimage. Test areas cover northern Taiwan. Test images are from SPOT 5 satellite. Experimental results indicate that proposed method improves the relative accuracy significantly.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.573-575
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• 2003

In satellite spectra, Though the magnitude varies with intensity of sunstroke, dip angle of land so on, the shape is less deformed with these effects. from this point of view, we have developed a spectral shape-dependent analysis utilizing a normalization procedure by the spectral integral and applied it to Landsat/TM spectra. Inevitable topographic and atmospheric effects can be suppressed. The correction algorithm is very simple and timesaving and the suppression of topographic effects is especially effective. Normalized band 4 is almost linear to NDVI values, and is available to the vegetation index.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.63-66
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• 2003

The electrophoretic deposition method has the advantage of relatively few fabrication facilities and simple process procedure as well as the economical and technical merit of allowing various forms of deposition and easy control of deposition thickness and wire length. A study, especially electric field and additive, on the optimization method to increase the density of particles and uniformity of their orientation have been performed to overcome the cracking and the porosity problems in the fabricated superconductor.

• International Journal of Highway Engineering
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• v.16 no.1
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• pp.21-30
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• 2014

PURPOSES : Evaluation of input parameters determination procedure for dynamic analysis of aggregates in DEM. METHODS : In this research, the aggregate slump test and angularity test were performed as fundamental laboratory tests to determine input parameters of spherical particles in DEM. The heights spreads, weights of the simple tests were measured and used to calibrate rolling and static friction coefficients of particles. RESULTS : The DEM simulations with calibrated parameters showed good agreement with the laboratory test results for given dynamic condition. CONCLUSIONS : It is concluded that the employed calibration method can be applicable to determine rolling friction coefficient of DEM simulation for given dynamic conditions. However, further research is necessary to connect the result to the behavior of aggregate in packing and mixing process and to refine static friction coefficient.

• The Journal of Engineering Research
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• v.4 no.1
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• pp.35-45
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• 2002

This paper deals with the scheduling problems which are the most important subtask in High-Level Synthesis. Especially, we have concentrated our attentions on the data-path scheduling which can get the structural informations from the behavioral algorithm as a first step in synthesis procedure. Suggest Forward scheduling methode is executed the ASAP and ALAP scheduling to use the fifth – order elliptic wave filter of a standard benchmark model, and then it is drawing up T.N matrix table by the number of resource and control-step, using the table extract of the simple than down-limit value of the control-step for the number of given resource to use this table. All of existing list scheduling techniques determine the priority functions first, and then do the operation scheduling, But, the suggested forward scheduling technique does the schedule first, and determines the priority functions if needed in scheduling process.

• Journal of Chest Surgery
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• v.16 no.3
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• pp.386-390
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• 1983

One case of surgically treated sliding esophageal hiatal hernia associated with bleeding gastric ulcer is presented. The patient was 73 years-old woman who had suffered from epigastric heartburn, indigestion, and melena since 3 months prior to admission. Esophageal hiatal hernia was suspected on the simple chest film and the diagnosis was confirmed by tetralogic barium study of the gastrointestinal tract. Hematemesis and melena were persisted so emergent thoracotomy and abdominal exploration were undertaken. Repair of hiatal hernia by constricting suture around relaxed esophageal hiatus was made and plication sutures were Inserted between esophagogastric junction and median arcuate ligament of diaphragm. Concomittently, subtotal gastrectomy with Billroth II procedure was performed to removal of large bleeding ulcer on the lesser curvature of the stomach antrum. Postoperative course was uneventful.

• Journal of Chest Surgery
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• v.25 no.7
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• pp.707-710
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• 1992

Percutaneous needle aspiration has been widely used in the diagnosis of pulmonary lesions, because it is a fairly simple procedure with good diagnostic accuracy and low complication rate. Among its complications, the spread of malignant cells along the needle tract is rare but serious one. We report a case of chest wall implantation of lung cancer after the percutaneous fine needle aspiration biopsy. A 57-year-old man had undergone a right upper lobectomy for squamous cell carcinoma [T2N0M0] of the lung, 3 months after the operation, a growing mass, located far from the previous thoracotomy incision, developed on the right anterior chest wall where the diagnostic thin needle biopsy had been performed before the lobectomy. A wide excision of the chest wall mass was performed, and permanent histology showed squamous cell carcinoma as noted before.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.972-975
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• 2004

In order to reduce the noise of BLDC motor, a systematic optimization procedure for rotor structure is presented. The noise index is defined as the sum of volume velocity of FE-model that are calculated at the dominant frequencies during dehydration process, which is based on the principle of radiation simple volume source. Then, the five design variables are selected to represent the shape and layout or rotor structure. This discrete design optimization problem for minimizing the noise index is solved by 3-level orthogonal array based effect analysis. Finally, the response surface method (RSM) combined optimization approach is employed for more refining the approximate optimum.