• International Journal of Concrete Structures and Materials
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• v.2 no.1
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• pp.41-48
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• 2008

This study investigates the spalling properties of high strength concrete designed with various types of mineral admixture and diverse content ratios of polypropylene (PP) fiber. Experimental factors considered in series I are four pozzolan types of mineral admixture and series II consists of three shrinkage reducing types of mineral admixture. PP fiber was added 0.05, 0.10 and 0.15vol. % in each mixture of series I and series II, so that totally 27 specimens including control concretes in each series were prepared. Test results showed that the increase of fiber content decreased the slump flow of fresh concrete and increased or decreased the air content depending on the declining ratio of slump flow. For the properties of compressive strength, all specimens were indicated at around 50 MPa, which is high strength range; especially all specimens in series II were 60 MPa. Fire test was conducted in standard heating curve of ISO 834 with ${\phi}100{\times}200\;mm$ size of cylinder moulds for 1 hour. The specimens incorporating silica fume exhibited severe spalling and most specimens without the silica fume could be protected from the spalling occurrence in only 0.05vol % of PP fiber content. This fire test results demonstrated that the spalling occurrence in high strength concrete was not only affected by concrete strength related to the porosity of microstructure but also, even more influenced by micro pore structure induced by the mineral admixtures.

• Neonatal Medicine
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• v.28 no.3
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• pp.116-123
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• 2021

Purpose: The aim of this study was to estimate the effect of targeting risk factors for the control of central line-associated bloodstream infection (CLABSI) among high-risk infants in a tertiary neonatal intensive care unit (NICU). Methods: Infants admitted to the NICU and diagnosed with CLABSI from January to December 2013 were eligible for inclusion to the study. The CLABSI group (n=47) was matched in a 1:2 ratio to the control group (n=94) based on gestational age, birth weight, and Score for Neonatal Acute Physiology-II. Risk factors for CLABSI were identified using the Cox proportional hazard model, and analysis of the effect of these risk factors targeting infection control was performed. Results: The risk factors associated with CLABSI were prolonged central line dwell days (adjusted hazard ratio [HR], 1.028; 95% confidence interval [CI], 1.011 to 1.045; P=0.001), use of a silicone catheter (adjusted HR, 5.895; 95% CI, 1.893 to 18.355; P=0.002), surgical treatment (adjusted HR, 3.793; 95% CI, 1.467 to 9.805; P=0.006), and less probiotic supplementation (adjusted HR, 0.254; 95% CI, 0.068 to 0.949; P=0.042). By targeting these risk factors with a quality improvement initiative, the mean CLABSI incidence rate per 1,000 catheter-days decreased from 6.6 to 3.1 (P=0.004). Conclusion: Targeting risk factors for infection control significantly reduced the rate of CLABSI among high-risk infants in the NICU.

• Journal of Korean Neurosurgical Society
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• v.41 no.1
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• pp.11-15
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• 2007

Objective : The authors attempted to confirm the risk factors for recurrent chronic subdural hematoma[CSDH] after simple burr-hole drainage. Methods : A total of 302 patients with CSDH who were treated at our hospital between January 1998 and May 2005 were studied. Various parameters considered for analysis of factors associated with CSDH recurrence; demographic and clinical findings [age, sex, history of seizures, diabetes, vascular diseases], initial and perioperative CT findings [hematoma density, location of catheter tip, post operative intracranial air, intracranial hematoma extension, hematoma width, hematoma site]. Results : Twenty-four patients [7.9%] experienced recurrence, whereas 278 patients [92.1%] did not. Five major risk factors should be considered : 1) layered type by hematoma density, 2) type I, II by location of catheter tip, 3) presence of postoperative intracranial air, 4) cranial base type of intracranial hematoma extension, 5) greater hematoma width. Conclusion : In this study, we report that the incidence of postoperative CSDH recurrence can be reduced by the examination of the hematoma characteristics on initial and perioperative CT findings and by preventing subdural air accumulation during operation. In addition, the location of the catheter tip can be used as a helpful factor in reducing the recurrence.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.79.1-79
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• 2003

Two pathogen-induced hot pepper transcription factors (CaNACl and CapIfl) were introduced into‘MicroTom’tomato by Agrobacterium tumefaciens-mediated transformation. We used to nptII containing kanamycin resistance gene as a selection marker. Both transformed and non-transformed plants were transferred to pot after rooting test in vitro. To approximate the levels of caNACl transcript in leaves of wild-type and transgenic plants, RNA blots were hybridized with double-stranded full-length CaNACl probe at moderate stringency, Although the relative signal strength for hybridization fluctuated among the samples on different blots, transgenic plant lines N-1, N-2 and N-3 consistently displayed increased levels of CaNACl transcript relative to other transgenic lines and wild-type plants. Of all the transgenic lines examined, line N-7 had the least amount of CaNACl transcript. Role of these transcription factors in pathogen defense will be examined by overexpression in tomato.

• Management Science and Financial Engineering
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• v.16 no.1
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• pp.1-16
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• 2010

In Nigeria, Igbemo-Ekiti is synonymous with a popular local rice which, nevertheless, is characterized with contaminations. Efforts of Government through the Agricultural Development Project (ADP) to improve rice quality in the state, have failed to yield the desired results. This study, therefore, reports the peculiar factors influencing the processing of rice in Igbemo-a major local producing town in Ekiti State, Nigeria. 72 respondents were interviewed, which was a census of the rice processors in 21 residential quarters of the town. Using the multiple linear regression models for analysis, the study discovered that; (i) status of the processors, (ii) expenditure on processing (iii) training acquired before commencing work, and (iv) storage facilities are crucial factors impacting rice processing activities in the town. The paper canvasses for policy measures based on research findings.

• Journal of the Korean housing association
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• v.11 no.1
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• pp.25-36
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• 2000

The purpose of this study was to analysis housing life styles of apartment dwellers by alteration in Ulsan, got hold of the influencing variables of housing life styles and indicated source materials about the plan of alteration of apartment dwellers. As a methodology for this study, questionnaire survey were used. The number of 228 cases were analyzed through SPSS PC+. For the analysis of the data, such techniques were used as reliability analysis, frequence analysis, factor analysis, correlation analysis, and multiple regression analysis.The major findings of this study were as followings: 1. Housing life styles of apartment dwellers by alteration in Ulsan identified five factors. In order of decreasing importance, these factors included: i)practicality, ii)ornament, iii)the faculty of space, iv) actuality, and v) spending habits. 2. The size of a family, wife's education, income, cost of alteration, and the area of installment sale were the most significant factors that influenced housing life styles of apartment dwellers by alteration in Ulsan.

• Journal of the Korea Institute of Military Science and Technology
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• v.7 no.1
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• pp.47-58
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• 2004

Loss factors of A356, Mn-Cu alloy and aluminum matrix composites reinforced with $SiC_p$ and Ni-coated graphite particles at various contents have been investigated using clamped-free cantilever beam method. The loss factors of half-power bandwidth of the specimens were measured over a wide range of frequencies from 50 to 3300Hz. Among the specimens, Al-10%$SiC_p$-10%$C_p$ showed the highest loss factor at the mode I, while Mn-Cu alloy showed the highest loss factors at the modes II and III. Consequently, at the mode I the Al-10%$SiC_p$--10%$C_p$ showed the loss factor of 0.00093, which is 2.64 and 1.58 times higher than those of A356 and Mn-Cu alloy, respectively.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.1
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• pp.121-126
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• 1994

A mutual integral, which has the conservation property, is applied to the problem of a crack in an isotropic elastic material. The stress intensity factors $K_{I}, K_{II}, K_{III}$ and T-stress for the problem in an infinite medium are easily obtained by using the mutual integral without solving the boundary value problem. The auxiliary solutions necessary in the proposed method are taken from the known asymptotic solutions. This method is amenable to numerical evaluation of the stress intensity factors and T-stress if the crack in a finite medium is considered.

• Journal of Korean Neurosurgical Society
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• v.52 no.1
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• pp.14-20
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• 2012

Objective : Intracranial meningiomas are primarily benign tumors with a good prognosis. Although WHO grade II meningiomas are rare (2-10%), WHO grade II meningiomas have higher recurrence and mortality rates than benign. We evaluated the patient recurrence rate and investigated the prognostic factors of WHO grade II meningiomas. Methods : Between 1993 and 2005, 55 patients were diagnosed with WHO grade II meningiomas in our hospital. WHO grade II meningiomas (n=55) were compared with other WHO grades meningiomas (I, n=373; and III, n=20). The patients had a median age of 48.4 years (range, 14-17 years), a male-to-female ratio of 26 : 29, and a mean follow-up time of 45 months (range, 3-175 months). Results : In WHO grade II meningiomas, only the extent of resection was a significant prognostic factor. Post-operative radiotherapy had no significant influence on tumor recurrence (p=0.053). The relative risk of recurrence was significantly higher in WHO grade II meningiomas with incomplete resection (10/27, RR=37%) than in WHO grade II meningiomas with complete resection (4/28, RR=14%) regardless of post-operative radiotherapy. In the incomplete resection group, Simpson grade III or IV had a significantly high risk of recurrence regardless of post-operative RT (n=3, RR=100%) However, if the degree of resection was Simpson grade II, the recurrence rate was similar to the complete resection group even though post-operative RT was not performed. Conclusion : Complete resection was the most powerful independent predictive factor of the recurrence rate in WHO grade II meningiomas. Post-operative adjuvant RT was not a significant factor in this study.

• Magazine of the Korean Society of Agricultural Engineers
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• v.28 no.3
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• pp.69-78
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• 1986

This studies were established to find out the characteristics of frequency distributiom for the number of occurrence and magnitude, probable flood flows according to the return periods, design floods, and design frequency factors for the studying basins in relation to the risk levels which can be correlated with design return period and the life of structure in the non-annual exceedance series. Eight watersheds along Han, Geum, Nak Dong and Seom Jin river basin were selected as studying basins. The results were analyzed and summarized as follows. 1. Poisson distribution and Exponential distribution were tested as a good fitted distributions for the number of occurrence and magnitude for exceedance event, respectively,at selected watersheds along Han, Geum, Nak Dong and Seom Jin river basin. 2.Formulas for the probable flood flows and probable flood flows according to the return periods were derivated for the exponential distribution at the selected watersheds along Han, Geum, Nak Dong, and Seom Jin river basin. 3.Analysis for the risk of failure was connected return period with design life of structure in the non-annual exceedance series. 4.Empirical formulas for the design frequency factors were derivated from under the condition of the return periods identify with the life of structure in relation to the different risk levels in the non-annual exceedance series. 5.Design freguency factors were appeared to be increased in proportion to the return periods while those are in inverse proportion to the levels of the risk of failure. Numerical values for the design frequency factors for the non-annual exceedance series ware appeared generally higher than those of annual maximum series already published by the first report. 6. Design floods according to the different risk levels could be derivated by using of formulas of the design frequency factors for all studying watersheds in the nor-annual exceedance series.