• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.5
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• pp.1345-1359
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• 1996

This paper presents a floating point arithmetic unit (FPAU) for supescalar microprocessor that executes fifteen operations such as addition, subtraction, data format converting, and compare operation using two pipelined arithmetic paths and new rounding and normalization scheme. By using two pipelined arithmetic paths, each aritchmetic operation can be assigned into appropriate arithmetic path which high speed operation is possible. The proposed normalization an rouding scheme enables the FPAU to execute roundig operation in parallel with normalization and to reduce timing delay of post-normalization. And by predicting leading one position of results using input operands, leading one detection(LOD) operation to normalize results in the conventional arithmetic unit can be eliminated. Because the FPAU can execuate fifteen single-precision or double-precision floating-point arithmetic operations through three-stage pipelined datapath and support IEEE standard 754, it has appropriate structure which can be ingegrated into superscalar microprocessor.

• Journal of Chest Surgery
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• v.24 no.9
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• pp.918-925
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• 1991

The technique of sleeve lobectomy has emerged as a relatively recent mode of excisional therapy. Acceptance of the technique has been slow because initially it has believed to be more difficult technically, to be associated with more complications, and be an inadequate operation for cancer. Sleeve lobectomy for bronchogenic carcinoma is an alternative to pneumonectomy. Four patients with bronchogenic carcinoma were treated by lobectomy with sleeve resection of the bronchus from 1986 to 1990. Three patients were male and one patient was female. Ages ranged from 43 years to 68 years. Symptoms were cough, sputum, blood tinged sputum, and dyspnea. Histopathologically, 3 cases were squamous cell carcinoma, 1 case was adenocarcinoma. Preoperative stage was stage I in 3 cases and stage II in 1 case. All of them were alive after operation.

• Journal of Power System Engineering
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• v.7 no.4
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• pp.12-18
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• 2003

Various measures have been tried to reduce the NOx emission from diesel engine, but with partial success because the mechanisms of NOx and PM formations appear to have trade-off relation between each other. Therefore it has been known to be difficult to reduce NOx emission and PM emission simultaneously. Two stage combustion method i,e. a combustion process which has rich combustion stage and lean combustion stage one by one, has been developed successfully to reduce NOx formation in the continuous combustion chambers such as in the boilers. But until yet it is not successful to apply the same method in intermittent combustion chamber like in the diesel engine cylinder, as it was, only several research works were carried out. In this study, devised was a uniquely shaped combustion chamber with reformed piston crown intended to keep fuel-rich condition during early stage of combustion and fuel-lean condition during next stage. It was found that the NOx emission decreased significantly at various conditions of operation with the two stage combustion type engines of PR20 type, but other values such as smoke, CO and specific fuel consumption deteriorated as usual.

• Journal of Gastric Cancer
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• v.2 no.2
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• pp.105-114
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• 2002

In this study, the Korean Gastric Cancer Association collected 12,152 gastric cancer patients (5,380 in 1995, 6,772 in 1999) from 29 hospitals. Twelve clinicopathological factorssex, age, operation date, tumor location, size, operation method, gross type of early gastric cancer, Borrmann type, depth of invasion, lymph node metastasis, distant metastasis, stage-were summarized in a database file and analyzed. Chronological change has been evaluated between the patients in 1995 and those in 1999. Proportion of early gastric cancer has been increased from $28.6\%$ in 1995 to $32.8\%$ in 1999. The UICC staging was $25.3\%$ (1995), $29.3\%$ (1999) for stage Ia, $12.7\%,\;13.9\%$, for stage Ib, $15.7\%,\;14.8\%$, for stage II, $15.2\%,\;13.2\%$, for stage IIIa, $8.2\%,\;6.3\%$, for stage IIIb, and $20.1\%,\;18.1\%$, for stage IV. The operation of each year was subtotal gastrectomy ($67.6\%,\;67.3\%$), total gastrectomy ($26.6\%,\;24.1\%$), proximalgastrectomy ($0.3\%,\;3.6\%$), wedge resection ($0.1\%,\;0.5\%$), bypass surgery ($2.3\%,\;1.8\%$), and open biopsy ($3.1\%,\;2.7\%$). In early gastric cancer, type IIc was the most common ($44.5\%$ in 1995, $42.8\%$ in 1999). The incidence of upper one-third cancer was slightly increased in 1999 ($12.5\%$) than 1995 ($11.2\%$), which is reflected in the increased prox-imal gastrectomy in 1999 (207 cases, $3.6\%$). There was no significant difference between either groups regarding the regional differences.

• Journal of the Korean Operations Research and Management Science Society
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• v.4 no.1
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• pp.51-67
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• 1979

This paper considers the problem of determining an optimal dynamic operating policy for a two-stage tandem queueing service system in which the service facilities (or stages) can be operated at more than one service rate. At each period of the system's operation, the system manager must specify which of the available service rates is to be employed at each stage. The cost structure includes an operating cost for running each stage and a service facility profit earned when a service completion occurs at Stage 2. We assume that the system has a finite waiting capacity in front of each station and each customer requires two services which must be done in sequence, that is, customers must pass through Stage 1 and Stage 2 in that order. Processing must be in the order of arrival at each station. The objective is to minimize the total discounted expected cost in a two-stage tandem queueing service system, which we formulate as a Discrete-Time Markov Decision Process. We present analytical and numerical results that specify the form of the optimal dynamic operating policy for a two-stage tandem queueing service system.

• Advances in pediatric surgery
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• v.7 no.2
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• pp.130-136
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• 2001

The aim of this study was to evaluate the short-term outcomes of the trans anal one-stage pull-through procedure(TOP) in Hirschsprung's disease. Eight patients aged 3 weeks to 8 months with Hirschsprung's disease underwent this procedure. A rectal mucosectomy was performed from just proximal to dentate line to the level of peritoneal reflexion, where muscle layer was incised circumferentially. Rectosigmoid was mobilized out through the anus, and full-thickness frozen biopsy was taken for confirmation of ganglionic cells. After the rectal muscular cuff was divided longitudinally in the posterior aspect, aganglionic bowel was removed and ganglionic colon was anastomozed to the anus. The mean operating time was 161 minutes, and the mean hospital stay after operation was 3.8 days. Five patients had three to four bowel movement per day without other therapy at mean postoperative 39.2 days. Although long-term follow-up will be required, the TOP might be the new alternative surgical procedure for Hirschsprung's disease.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.315-317
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• 2001

This paper studies for the optimal operation of BESS. The goal must be optimized electricity charge of the customer sides owned time-of-use rates in this paper. Therefore, the least of cost is caused by BESS installation, Multi-Pass Dynamic Programming (MPDP) algorithm is applied to the customer for the optimal operation determination in this paper. It is to solve the optimal solution under the constraints. No matter how become one stage in general, problem is divided into several stage in series in this algorithm. Regardless of the decision step, MPDP is only accomplished based on the state of stage in the present. To investigate the efficiencies of the algorithm, it is applied the typical load curve to the cutomer owned Time-Of-Use(TOU). Result shows that the maximun economic benefits of the battery energy storage system can be achieved by the purposed algorithm.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.1
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• pp.63-73
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• 2001

This paper presents a process and operation planning system with an NC code post-processor for effective machining of press dies for production of cars. Based on the machining features, major parts of press dies are categorized into 15 groups and a standard process plan is defined for each group. The standard process plan consists of a series of processes where a process is defined as a group of operations that can be done with one setup. Details such as cutting tools, cutting conditions, and tool paths are decided at the operation planning stage. At the final stage of process and operation planning, the NC code post-processor we developed adjusts feedrates along the tool path to reduce machining time. The adjustment rule is selected based on the metal removal rate estimated by virtually machining with virtual cutting tool.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.5
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• pp.425-431
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• 2006

The development of fermentation conditions for the production of C595 diabody fragment (dbFv) in E. coli HB2151 clone has been explored. Investigations were carried out to study the effect of carbon supplements over the expression period, the comparison of C595 dbfv production in synthetic and complex media, the influence of acetic acid upon antibody production, and comparison of one-stage and two-stage processes operated at batch or fed-batch modes in bioreactor. Yeast extract supplied during expression yielded more antibody fragment than any other carbon supply. The synthetic medium presented higher specific productivity (0.066 mg dbFv $g^{-1}$ dry cell weight) when compared to the complex medium (0.044 mg dbFv $g^{-1}$ DCW). The comparison of fermentation strategies demonstrated that (1) one-stage fed-batch fermentation performed higher C595 dbFv production than that operated in batch mode which was significantly affected by acetate concentration; (2) a two-stage batch operation could enhance C595 dbFv production. It was found that a concentration of 12.3 mg $L^{-1}$ broth of C595 dbFv and a cell concentration of 10.8g $L^{-1}$ broth were achieved at the end of two-stage operation in 5-L fermentation.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.238-241
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• 1999

Analog-to-digital converter has attracted a lot of interests as one of the most prospective area of an application of Josephson Junction technology. Recently, the development of a digital-to-analog converter has been pursued to achieved the high performance. One of the main advantage in using single flux quantum logic in a digital-to-analog converter is the low voltage drop in a single Josephson Junction and hence the resolution of the output voltage of this digital-to-analog converter can be very high. In this work, we have used a software, called WRspice, to study a voltage multiplier circuit which is the basic block in building a digital-to-analog circuit. In simulation, we operated a voltage multiplier with .4 Josephson Junctions per stage and studied the dependence on the circuit bias currents and the circuit inductors of the voltage multiplier. Our simulation results showed a fast operation and reasonable circuit margins.