• Kyungpook Mathematical Journal
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• 제62권3호
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• pp.467-484
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• 2022

In this work, we define bivariate Bernstein-Kantorovich type operators on a triangular domain and obtain some approximation results for these operators. We start off by computing some moment estimates and prove a Korovkin type convergence theorem. Then, we estimate the rate of convergence using the partial and complete modulus of continuity, and derive a Voronovskaya-type asymptotic theorem. Further, we calculate the order of approximation with regard to the Peetre's K-functional and a Lipschitz type class. In addition, we construct the associated GBS type operators and compute the rate of approximation using the mixed modulus of continuity and class of the Lipschitz of Bögel continuous functions for these operators. Finally, we use the two operators to approximate example functions in order to compare their convergence.

• 한국진공학회지
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• 제4권S1호
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• pp.130-137
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• 1995

Deopsition of thermal quality SiO2 using a high density plasma ECR CVD process has been demonstrated to give void and seam free gap fill of high aspect ratio metallization structures with a simple oxygen-silane chemistry. This is achieved by continuous sputter etching of the film during the deposition process. A two-step process is utilized to deposit a composite layer for higher manufacturing efficiency. The first step, which has a deposition rate of approximately 0.5 $\mu$m/min., is used to provide complete gap fill between the metal lines. The second step, which has a deposition rate of up to 1.5 $\mu$m/min., is used to deposit a total thickness of 2.0$\mu$m for the intermetal dielectric film. The topography of this composite film is very compatible with subsequent chemicl mechanical polishing(CMP) planarization processing.

• Kyungpook Mathematical Journal
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• 제63권1호
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• pp.45-60
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• 2023

In this paper we suggest an enhanced Geraghty-type contractive mapping for examining the existence properties of classical nonlinear operators with or without prior degenerates. The nonlinear operators are proved to exist with the imposition of the Geraghty-type condition in a non-empty closed subset of complete metric spaces. To showcase some efficacies of the Geraghty-type condition, convergent rate and stability are deduced. The results are used to study some asymptotic properties of perturbed integral and hypergeometric operators. The results also extend and generalize some existing Geraghty-type conditions.

• 대한수의학회지
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• 제64권1호
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• pp.4.1-4.5
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• 2024

In this study, almost complete genomic sequences of porcine parvovirus (PPV)1 and PPV4 circulating in commercial pig farms in South Korea were obtained and analyzed. Important mutations that may be precursors to host changes, such as premature stop codons of PPV1 and frameshift mutations of PPV4, were observed in these sequences. A 27a-like strain of PPV1, known to show a lack of cross- neutralization against existing commercial vaccine strains, was identified by phylogenetic analysis. Given the active genetic evolution, the additional precursors to host changes and emerging new genotypes of PPVs need to be monitored through continuous sampling and genetic analysis.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제13권4호
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• pp.405-411
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• 1991

To determine the sterility of the prepared allogeneic bone of the human, culture of the allografts prior to implantation was performed on fresh-frozen and freeze-dried bone. Before the use of allografts to the patients, it must be confirmed about the sterility, cellular cytotoxicity, immune reaction, and osteoinductive potential as a biomaterials. Oral and maxillofacial surgeons demand for allograft bone will be increased in the future. Wonkwang Bone Bank attempted to meet this demand, has performed series of experimental study on the allograft bone of the Koreans to evaluate the physical and chemical suitability of the bone since the surgeons applications will have broadened from benign cystic lesions to fracture malunions and non-unions, large segmental defects, and whole-bone allorgrafts after tumor surgery. The results obtained were as follows: 1. Freeze-drying(FD) only shoed some bactericidal effects of the normal and osteo bone but in cases of performing EO gas sterilization, the FD effects was not clear. 2. The fact that FD has little effect than the EO gas sterilization on normal bone postulated that the presence of microbiota may be due to an operation and bone processing procedure. 3. FD and EO gas sterilization had a remarkable effect on the osteo bone. 4. The sterilization effect were EO gas, Freeze-drying, Fresh-Frozen with descending order. But all sterilization method were not complete to preserve and implant allograft bone. We are now performing further continuous study on the radiation and chemical sterilization procedure to make safe and complete allograft bone.

• 한국광물학회지
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• 제11권2호
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• pp.117-125
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• 1998

Crystallization behavior of platinum minerals within Pt-Sb-Bi bearing ore magmas and mineralogical properties of the existing minerals were investigated at 1,00$0^{\circ}C$ by synthetic experiment. High purity reagents were used as starting materials and silica tubings as containers. Reaction products were analysed by reflecting microscopy, X-ray diffraction, electron probe microanalysis, and micro-hardness test. Stable minerals at 1,00$0^{\circ}C$ are platinum, electron probe microanalysis, and micro-hardness test. Stable minerals at $1,000^{\circ}C$ are platinum, stump-flite (PtSb) and geversite (PtSb2). They are in equilibrium with liquid (ore magma). Platinum contains considerable amount of Sb of 7.5 at.%, whereas Bi only up to 0.9 at.%. Pure stumpflite is hexagonal with space group P63/mmc, and unit cell parameters are a=4.1318(6), c=5.483(1)$\AA$. VHN50=417(2)$\AA$. Geversite has cubic structure with space group Pa3. Cell parameters are a=6.4373(2)$\AA$ and Vicker hardness values VHN50=663.5 (566~766). Both stumpflite and geversite show solid solution and their end-members are Pt48.8Sb40.7-Bi10.5, and Pt33.7-Sb59.8Bi6.5, respectively. Although stumpflite (m.p. $1,043^{\circ}C$) and unnamed PtBi (m.p. 7$65^{\circ}C$) do not form a complete solid solution at $1,000^{\circ}C$, they are known, at $600^{\circ}C$, to form a continuous solid solution. Geversit (m.p. $1,226^{\circ}C$) also forms complete solid solution with insizwaite (m.p. $660^{\circ}C$). Unit cell dimensions of the minerals above increases with the amount of Bi substituting for Sb.

• Radiation Oncology Journal
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• 제34권2호
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• pp.106-112
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• 2016

Purpose: To identify possible predictors of pathologic complete response (pCR) of rectal cancer after preoperative concurrent chemoradiotherapy (CCRT). Materials and Methods: We conducted a retrospective review of 53 patients with rectal cancer who underwent preoperative CCRT followed by radical surgery at a single center between January 2007 and December 2012. The median radiotherapy dose to the pelvis was 54.0 Gy (range, 45.0 to 63.0 Gy). Five-fluorouracil-based chemotherapy was administered via continuous infusion with leucovorin. Results: The pCR rate was 20.8%. The downstaging rate was 66%. In univariate analyses, poor and undifferentiated tumors (p = 0.020) and an interval of ${\geq}7$ weeks from finishing CCRT to surgery (p = 0.040) were significantly associated with pCR, while female gender (p = 0.070), initial carcinoembryonic antigen concentration of <5.0 ng/dL (p = 0.100), and clinical stage T2 (p = 0.100) were marginally significant factors. In multivariate analysis, an interval of ${\geq}7$ weeks from finishing CCRT to surgery (odds ratio, 0.139; 95% confidence interval, 0.022 to 0.877; p = 0.036) was significantly associated with pCR, while stage T2 (odds ratio, 5.363; 95% confidence interval, 0.963 to 29.877; p = 0.055) was a marginally significant risk factor. Conclusion: We suggest that the interval from finishing CCRT to surgery is a predictor of pCR after preoperative CCRT in patients with rectal cancer. Stage T2 cancer may also be an important predictive factor. We hope to perform a robust study by collecting data during treatment to obtain more advanced results.

• Tribology and Lubricants
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• 제38권3호
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• pp.73-83
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• 2022

This paper is concerned with an analysis of a surface edge crack emanated from a sharp contact edge. For a geometrical model, a square wedge is in contact with a half plane whose materials are identical, and a surface perpendicular crack initiated from the contact edge exists in the half plane. To analyze this crack problem, it is necessary to evaluate the stress field on the crack line which are induced by the contact tractions and pseudo-dislocations that simulate the crack, using the Bueckner principle. In this Part I, the stress filed in the half plane due to the contact is re-summarized using an asymptotic analysis method, which has been published before by the author. Further focus is given to the stress field in the half plane due to a pseudo-edge dislocation, which will provide a stress solution due to a crack (i.e. a continuous distribution of edge dislocations) later, using the Burgers vector. Essential result of the present work is the corrective functions which modify the stress field of an infinite domain to apply for the present one which has free surfaces, and thus the infiniteness is no longer preserved. Numerical methods and coordinate normalization are used, which was developed for an edge crack problem, using the Gauss-Jacobi integration formula. The convergence of the corrective functions are investigated here. Features of the corrective functions and their application to a crack problem will be given in Part II.

• 한국의류산업학회지
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• 제3권5호
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• pp.466-472
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• 2001

To find a suitable condition in this process examined, we investigated the main control factors, such as, the NaOH concentrations, such as, the NaOH concentrations, the heat treating times, and the heating temperatures. The resulting mechanical properties of the fabrics also studied. The samples used were Nylon/Co-PET sea-island type composite microfiber (Co-PET content: 35%) non-woven fabric. The conclusions obtained were as follows. 1. For the complete extraction of Co-PET from the sample non-woven fabric in the dry hot air process, $160^{\circ}C$ of air temperature, 15 min. of treatment time, and around 30% of NaOH concentration were required. On the other hand, in the wet hot air process, $140^{\circ}C$ of air temperature, 3.5 min. of treatment time, and around 30% of NaOH concentration were required. 2. The mechanical properties of the continuous processed samples showed that the WT, B, and WC increased with increasing the weight reduction ratio. However, the G, decreased with increasing the weight loss ratio. Note that, particularly in B, it increased drastically when the weight deduction ratios exceeded 30%. 3. As increasing the wet hot air temperature from 130 to $140^{\circ}C$, B appeared to increase, however, WT, G, and WC appeared to decrease. 4. The best condition found in this continuous process to extract Co-PET is the wet hot air temperature of 140, NaOH concentration of 28% or above, and the treatment time 2-4 min.

• 생명과학회지
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• 제20권10호
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• pp.1563-1568
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• 2010

암(dark) 상태에서 재배한 대두의 하배축 길이 생장의 분자 기작을 연구하기 위한 일환으로 암 상태에서 재배한 대두 하배축으로부터 cDNA library를 제작한 후 ESTs를 구축하였다. 이들 ESTs 중 색소체 ABC 단백질과 아미노산 서열이 매우 유사한 clone을 선발한 후 이 유전자의 전체염기서열을 결정하였다. GmNAP1 단백질은 엽록체로 향하는 transit peptide 서열이 존재한다. 빛에 의해 GmNAP1 유전자 전사가 어떻게 변화되는지 알아보기 위해 지속적인 적색광, 근적색광 그리고 암 상태에서 성장시키면서 유전자의 전사량을 확인하였다. 이 색소체 NAP1는 엽록소의 전구 물질인 protoporphytin IX를 세포질에서 엽록체로 이동시키는 기능을 한다. 대두에서 분리된 GmNAP1 유전자의 기능을 확인하기 위하여 35S 프로모터 뒤에 GmNAP1 유전자를 접합한 후 애기장대에 형질전환하였다. 형질전환 된 애기장대의 엽록소 함량은 야생형의 엽록소 함량보다 훨씬 높게 측정되었다.