• The Bulletin of The Korean Astronomical Society
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• v.33 no.1
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• pp.43.1-43.1
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• 2008

• The Bulletin of The Korean Astronomical Society
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• v.32 no.1
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• pp.68.2-68.2
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• 2007

• The Bulletin of The Korean Astronomical Society
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• v.34 no.1
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• pp.118.1-118.1
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• 2009

• Advances in pediatric surgery
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• v.2 no.2
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• pp.81-87
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• 1996

Although nonoperative reduction plays a major role in the management of uncomplicated intussusception in the pediatric age group, surgical treatment is still a necessary alternative when nonoperative reduction is unsuccessful. The author analyzed the clinical features of 68 patients requiring operation in order to identify factors which might influence the type of operative management. A nine-year experience at Ewha Womans University Hospital was reviewed, and the findings compared to previous reports. Barium was used for the initial reduction attempt in 33 cases, saline in 35. Manual reduction by milking at operation achieved success in 41 cases(60.3%). Fifteen cases(22.1%) required resection of bowel, and 12 patients(17.6%) were found to have spontaneous and complete reduction of the intussusception at operation. Two cases had pathologic leading points. There were no perforations due to nonoperative reduction. There were no significant differences in demographic data, clinical findings, laboratory data, and anatomic type of intussusception between barium and saline reduction groups. However, a significant number of cases with spontaneous reduction were in saline reduction group(p<0.05). There was a slight chance of spontaneous reduction in infants under 6 month of age(p<0.001). Age under 6 month. body temperature over $38^{\circ}C$, symptom over 24 hours, and ileo-colic and ileo-ileo-colic intussusception contributed significantly to the necessity for bowel resection(p<0.05-0.001). The author believes that the age, body temperature, duration of illness, and anatomic type of intussusception strongly influence operative management.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.15 no.7
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• pp.553-564
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• 1990

The co-efficient matrix of linear second-order partial differential equations in the general form is partitioned with (n-1)x(n-1) submartices and is transformed into the block tridiagonal system. Then the cyclic odd-even reduction technique is applied to this system with the large-grain data granularity and the block cyclic reduction algorithm to solve unknown vectors of this system is created. But this block cyclic reduction technique is not suitable for the parallel processing system because of its parallelism chanigng at every computing stages. So a new algorithm for solving linear second-order partical differential equations is presentes by the block cyclic reduction technique which is modified in order to keep its parallelism constant, and to reduce gteatly its execution time. Both of these algoriths are compared and studied.

• Journal of the Society of Naval Architects of Korea
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• v.40 no.3
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• pp.9-15
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• 2003

An experimental study has been carried out as a basic research for development of the friction drag reduction technology for ships by polymer injection. Experimental apparatus and procedures have been devised and prepared to measure the changes of the wall friction with injection of a polymer solution and basic experimental data on the friction drag reduction are obtained for a turbulent fiat-plate boundary layer and fully-developed channel flows. Variations of the friction drag reduction with some important parameters of polymer injection, such as the concentration of polymer solution, its injection flow rate and the measuring position downstream from the injection slot, are also investigated. Important experimental data and results obtained in the present study are presented. The amount of friction drag reduction up to 50% is observed.

• Communications for Statistical Applications and Methods
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• v.28 no.2
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• pp.205-215
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• 2021

Sufficient dimension reduction is useful dimension reduction tool in regression, and sliced inverse regression (Li, 1991) is one of the most popular sufficient dimension reduction methodologies. In spite of its popularity, it is known to be sensitive to the number of slices. To overcome this shortcoming, the so-called fused sliced inverse regression is proposed by Cook and Zhang (2014). Unfortunately, the two existing methods do not have the direction application to large p-small n regression, in which the dimension reduction is desperately needed. In this paper, we newly propose seeded sliced inverse regression and seeded fused sliced inverse regression to overcome this deficit by adopting iterative projection approach (Cook et al., 2007). Numerical studies are presented to study their asymptotic estimation behaviors, and real data analysis confirms their practical usefulness in high-dimensional data analysis.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.291-298
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• 2003

The resonant column testing is a laboratory testing method to determine the shear modulus and the material damping factor of soils. The method has been widely used for many applications and its importance has been increased. Since the establishment of the testing method in 1963, the low-technology electronic devices for testing and data acquisition have limited the measurement to the amplitude of the linear spectrum. The limitations of the testing method were also attributed to the assumption of the linear-elastic material in the theory of the resonant column testing and to the use of the wave equation for the dynamic response of the specimen. For the better theoretical formulation of the resonant column testing, this study derived the equation of motion and provided its solution. This study also proposed the improved data reduction and analysis method for the resonant column testing, based on the advanced data acquisition system and the proposed theoretical solution for the resonant column testing system. For the verification of the proposed data reduction and analysis method, the numerical simulation of the resonant column testing was performed by the finite element analysis. Also, a series of resonant column testing were peformed for Joomunjin sand, which verified the feasibility, of the proposed method and showed the limitations of the conventional data reduction and analysis method.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.2
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• pp.13-19
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• 2006

The instance-based learning is a machine learning technique that has proven to be successful over a wide range of classification problems. Despite its high classification accuracy, however, it has a relatively high storage requirement and because it must search through all instances to classify unseen cases, it is slow to perform classification. In this paper, we have presented a new data reduction method for instance-based learning that integrates the strength of instance partitioning and attribute selection. Experimental results show that reducing the amount of data for instance-based learning reduces data storage requirements, lowers computational costs, minimizes noise, and can facilitates a more rapid search.

• Bulletin of the Korean Chemical Society
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• v.22 no.5
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• pp.488-492
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• 2001

As gas chromatography/infrared spectrometry (GC/IR) becomes routinely avaliable, methods must be developed to deal with the large amount of data produced. We demonstrate computer methods that quickly search through a large data file, locating thos e spectra that display a spectral feature of interest. Based on a modified library search routine, these selective data reduction methods retrieve all or nearly all of the compounds of interest, while rejecting the vast majority of unrelated compounds. To overcome the shifting problem of IR spectra, a search method of moving the average pattern was designed. In this moving pattern search, the average pattern of a particular functional group was not held stationary, but was allowed to be moved a little bit right and left.