• 대한의용생체공학회:의공학회지
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• 제26권1호
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• pp.43-47
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• 2005

We have developed a small bore x-ray CT for small animal imaging with a linear x-ray detector array and small-scale slip rings. The linear x-ray detector array consists of 1024 elements of 400□m×400□m with a gadolinium oxysulfide (GOS) scintillator on top of them. To avoid use of expensive large diameter slip rings for projection data transmission from the X­ray detector to the image reconstruction system, we used the wireless LAN technology. The projection data are temporally stored in the data acquisition system residing on the rotating gantry during the scan and they are transmitted to the image reconstruction system after the scan. With the wireless LAN technology, we only needed to use small-scale slip rings to deliver the AC electric power to the X-ray generator and the power supply on the rotating gantry. The performances of the small animal CT system, such as SNR, contrast, and spatial resolution, have been evaluated through experiments using various phantoms. It has been experimentally found that the SNR is almost linearly proportional to the tube current and tube voltage, and the minimum resolvable contrast is less than 30 CT numbers at 40kVp/3.0㎃. The spatial resolution of the small animal CT system has been found to be about 0.9Ip/㎜. Postmortem images of a piglet is also presented.

• 대한두경부종양학회지
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• 제31권2호
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• pp.36-38
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• 2015

Small cell carcinoma is mainly found in the lungs and extrapulmonary origins of small cell carcinoma in GI tract, head and neck, genitourinary system consists only 4% of the tumor. Thus, small cell carcinoma of the parotid gland is an extremely rare disease. Extrapulmonary small cell carcinoma is characterized by an aggressive clinical course with early metastasis. We report a case of small cell carcinoma of parotid gland in a 82-year-old woman with painless neck mass, who was managed with radiation therapy after surgery and review of relevant literatures.

• 항공우주정책ㆍ법학회지
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• 제14권
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• pp.331-379
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• 2001

The purpose of this study is provide better suggestions to utilize the small aircraft by examining current situations of those airports. Then, the results of this study should help explain about the Availability of the airports for small aircraft in view of airplane exhibition, air-sports activity fields for aviation sports population, aviation theme park, and aviation-related education facility. This study examines current situations of the small airports for small aircraft which have been limited in their utility and compares the airports at the same level abroad. By examining these airports, this paper can make suggestions for the Availability of the small airports. Significance of the study lies in providing businessmen planning to invest the small airports and owners of airports with profitable consequences. At the macro level, it is expected to have a more effective development of land and an increase of aviation market value.

• 한국해양공학회지
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• 제3권2호
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• pp.601-601
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• 1989

The behavior of fatigue was studied by using low carbon steel bar with microhole(artificial small defect) under the condition of rotary bending stress which is made artificially at smooth surface and round notch root. The results obtained can be summerized; The behavior of non-propagating cracks which are produced at both tips of small defect occurred to dissymmetry, and it is found to be double size of small defect. For the range of l>lc, threshold stress intensity is constant. However, for the range of l

• Journal of the Korean Data and Information Science Society
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• 제28권1호
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• pp.207-215
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• 2017

In this paper we study pooling effects in Bayesian testing procedures of independence for contingency tables from small areas. In small area estimation setup, we typically use a hierarchical Bayesian model for borrowing strength across small areas. This techniques of borrowing strength in small area estimation is used to construct a Bayes test of independence for contingency tables from small areas. In specific, we consider the methods of direct or indirect pooling in multinomial models through Dirichlet priors. We use the Bayes factor (or equivalently the ratio of the marginal likelihoods) to construct the Bayes test, and the marginal density is obtained by integrating the joint density function over all parameters. The Bayes test is computed by performing a Monte Carlo integration based on the method proposed by Nandram and Kim (2002).

• Journal of the Korean Data and Information Science Society
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• 제15권1호
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• pp.1-10
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• 2004

In the Korean Economically Active Population Survey(EAPS), the sample sizes for small areas are typically too small to provide reliable estimators because the EAPS has been designed to produce unemployment statistics for large areas such as Metropolitan Cities and Province. In this study, we consider the synthetic and composite estimators for the unemployment rate of small areas, and apply them to real data on Choongbook province which is from the Korean EAPS of December 2000. The mean square errors of these estimators were estimated by the Jackknife method, and the efficiencies of small area estimators were evaluated in terms of the relative standard errors and the relative root mean square errors. As a result, the composite estimator is much more efficient than other estimators and it turns out that the composite estimator can produce the reliable estimates of the unemployment rate of small areas under the current EAPS system.

• 대한세포병리학회지
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• 제18권2호
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• pp.153-156
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• 2007

Primary small cell carcinoma of the urinary bladder is an extremely rare but important entity. We experienced a case of small cell carcinoma of the urinary bladder diagnosed by urine cytology. A 59-year-old man presented with gross hematuria and dysuria, and a calcified mass was detected at the left ureterovesical junction by cystoscopy. Abdominal ultrasonography revealed focal wall thickening at the left lateral side of the urinary bladder, and urine cytology findings were of an inflammatory background and atypical small round cells with minute hyperchromatic or pyknotic nuclei, scant cytoplasm, and rare nucleoli. In addition, atypical cells were scattered in an isolated single cell pattern or in small loose clusters with prominent nuclear molding. Subsequent histological and immunohistochemical examinations confirmed a diagnosis of small cell carcinoma.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1306-1307
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• 2011

Recently, the small scale photovoltaic (PV) electronic devices are drawing attention as the upcoming PV generation system. The PV system is commonly used in small scale PV applications such as LED lighting and cell phone. This paper proposes photovoltaic output sensorless (POS) maximum power point tracking (MPPT) control for a small scale charging system of PV-nickel metal hydride battery using field-programmable gate array (FPGA) controller. A converter is connected to a small scale PV cell and battery, and performs the POS MPPT at the battery terminal current instead of being at the PV cell output voltage and current. The FPGA controller and converter operate based on POS MPPT method. The experimental results show that the nickel metal hydride battery is charged by the maximum PV output power.

• 한국가스학회지
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• 제19권1호
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• pp.51-56
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• 2015

To assess downward positions of water spray for the small-scale release of chlorine gas, dispersion coefficients for the Gaussian dispersion model were validated at the small-scale release experiment. And the downwind distances of water spray were assessed with the simulated results. As results, the Gaussian plume model using the Briggs' dispersion coefficient well estimated the dispersed characteristics for small-scale release of chlorine gas. The best adequate downwind position of water spray is the position of the maximum concentration of chlorine at the ground level. And the adequate vertical and horizontal dimensions of water spray consider the maximum width and height of cloud.

• 대한세포병리학회지
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• 제5권2호
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• pp.167-171
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• 1994

Small cell carcinoma of the urinary bladder is a rare tumor which occurs in about 0.48 % of all bladder tumors. We report cytologic features of small cell carcinoma of the urinary bladder in a 66-year-old man who had painless total gross hematuria, which was confirmed by partial cystectomy. In urine cytology, abundant tumor cells appeared in scattered and clustered forms in a bloody background. The tumor cells were small and uniform in size with a high nuclear/cytoplasmic ratio. The nuclei of the tumor cells were hyperchromatic, characteristically molded and showed inconspicuous nucleoli. The cytoplasms were scanty and pale blue.