• Korean Journal of Materials Research
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• v.31 no.12
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• pp.719-726
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• 2021

Through the process of chemical vapor deposition, Tungsten Hexafluoride (WF₆) is widely used by the semiconductor industry to form tungsten films. Tungsten Hexafluoride (WF₆) is produced through manufacturing processes such as pulverization, wet smelting, calcination and reduction of tungsten ores. The manufacturing process of Tungsten Hexafluoride (WF₆) is required thorough quality control to improve productivity. In this paper, a real-time detection system for oxidation defects that occur in the manufacturing process of Tungsten Hexafluoride (WF₆) is proposed. The proposed system is implemented by applying YOLOv5 based on Convolutional Neural Network (CNN); it is expected to enable more stable management than existing management, which relies on skilled workers. The implementation method of the proposed system and the results of performance comparison are presented to prove the feasibility of the method for improving the efficiency of the WF₆ manufacturing process in this paper. The proposed system applying YOLOv5s, which is the most suitable material in the actual production environment, demonstrates high accuracy (mAP@0.5 99.4 %) and real-time detection speed (FPS 46).

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.939-944
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• 2002

We have screened the microorganisms from pigs feces for the development of probiotics which have acid-and bile-tolerance. Among them, a strain which was identified as Enterococcu durans LP44 was selected. Sixty Duroc$\times$Yorkshire$\times$Landrace pigs (6.30$\pm$0.04 kg average initial body weight) were used in a 14 days growth assay to determine the effects of Enterococco duran Lf44 culture on growth performance of weaned pigs. Dietary treatments included 1) DF (dry feeding),2) W (wet feeding),3) WF+5ED (wet feeding+5% Enterocucu duran LP44 culture),4) WF+ 10ED (wet feeding +10% Enterococcus durans LP44 culture). For overall periods, average daily gain in pigs fed % diet tended to increase compared to pigs fed DF diet without significant difference. Also, there was no significant difference in gain/feed. At 5 days after the onset of the experiment, pigs fed WF+5ED and WF+10ED diets were significantly increased in dry matter and nitrogen digestibilities compared to pigs fed DF and W diets (p<0.05). At 14 days after the onset of the experiment, pigs fed WF+ 10ED diet were significantly increased in dry matter digestibility compared to pigs fed DF diet (p<0.05). Also, pigs fed WF + 10ED diet were significantly increased in nitrogen digestibility compared to other treatments (p<0.05). In conclusion, supplemental Enterococcus durans LP44 was an effective means of improving ADG and nutrient digestibility.

• Journal of the Korean institute of surface engineering
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• v.50 no.3
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• pp.141-146
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• 2017

We investigated configuration of metallic and insulating domains in $VO_2$ thin films, while spanning metal-insulator phase transition. Kelvin probe force microscopy, of which spatial resolution is less than 100 nm, enables us to measure local work function (WF) at the sample surface. The WF of $VO_2$ thin films decreased (increased) as increasing (decreasing) the sample temperature, during the phase transition. The higher and lower WF regions corresponded to the insulating and metallic domains, respectively. The metallic fraction, estimated from the WF maps, well explained the temperature-dependent resistivity based on the percolation model. The WF mapping also showed us how the structural defects affected the phase transition behaviors.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.11a
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• pp.49-52
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• 2003

워크플로우 관리시스템(WfMS: Workflow Management System)은 업무 프로세스를 컴퓨터에 의해 정의, 실행 및 관리하기 위한 소프트웨어 시스템이다. WfMS에서는 업무 프로세스의 로직을 컴퓨터가 이해 가능한 언어로 표현하므로 다수의 사용자가 이기종의 분산된 환경에서 참여하는 업무 흐름을 관리 하는데에는 효율적이나 지식경영 측면에서의 지원은 미약하다. 본 연구에서는 WfMS 구조하에서 효과적인 지식 관리를 위해 인공지능 기법의 하나인 사례기반추론(CBR: Case Based Reasoning)을 활용하여 업무 흐름상에서 발생하는 지식을 생성, 저장, 추출되도록 하는 업무 지원 시스템을 개발한다. 지식의 생성을 위해 폼 기반 워크플로우 관리 시스템을 활용하고 CBR 엔진은 제약 조건의 형태로 이뤄지는 쿼리에 대해 유사 사례 추출을 담당한다. 사례 베이스의 저장 형식은 XML(extensible Markup Language)을 이용한다. 본 연구에서 개발된 업무 지원 시스템을 활용함으로써 업무 조정자만으로서의 WfMS의 한계를 벗어나 지식경영 도구로서의 WfMS를 기대할 수 있다.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.1
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• pp.80-90
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• 2016

Thanks to superior leakage energy efficiency compared to SRAM cells, STTRAM cells are considered as a promising alternative for a memory element in on-chip caches. However, the main disadvantage of STTRAM cells is high write energy and latency. In this paper, we propose a low-cost write filter (WF) cache which resides between the load/store queue and STTRAM-based L1 data cache. To maximize efficiency of the WF cache, the line allocation and access policies are optimized for reducing energy consumption of STTRAM-based L1 data cache. By efficiently filtering the write operations in the STTRAM-based L1 data cache, our proposed WF cache reduces energy consumption of the STTRAM-based L1 data cache by up to 43.0% compared to the case without the WF cache. In addition, thanks to the fast hit latency of the WF cache, it slightly improves performance by 0.2%.

• Journal of the Korean Wood Science and Technology
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• v.34 no.5
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• pp.88-97
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• 2006

Wood flour (WF)-recycled polypropylene (RPP) composites composed of 50% WF of Eucalyptus deglupta Blume species, 50% RPP, various contents of maleic anhydride (MAH) modifier (0; 1; 2; 5; 5; 7.5; and lo%), and 15% dicumyl peroxide (DCP) initiator (based on MAH weight) were subjected to weather for 1 year and subterranean termite (Coptotermes cuwignathus HOLMGREN) and dry wood termite (Cryptotermes cynocephalus LIGHT) for 3 and 4 weeks, respectively. WF-RPP composites with 2.5% MA modifier had tensile strength, breaking elongation and Young's modulus about 2.2, 2.3, and 1.2 times, respectively higher compared to MAH-free composites. The WF-RPP composites with or without MAH modifier had 5.5 times higher resistance to weather compared to RPP film alone. The color of the WF-RPP composites with or without MAH modifier became lighter after exposures to the weather. The WF-RPP composites with or without MAH modifier are resistant to subterranean termite Coptotermes curvignathus HOLMGREN and dry wood termite Cryptotermecs cynocephalus LIGHT under the experimental condition adopted.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.4 s.33
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• pp.29-35
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• 2004

We have deposited the W-N diffusion barrier on Si substrate with $NH_3$ pulse plasma enhanced atomic layer deposition (PPALD) method by using $WF_6$ and $NH_3$ gases. The $WF_6$ gas reacts with Si that the surface corrosion occurs severely, but the $NH_3$ gas incorporated with pulse plasma and $WF_6$ gas are easily deposited W-N thin film without Si surface corrosion. Because the $NH_3$ with pulse plasma can be active species dissociated and chemisorbed on Si. Thus the Si surface are covered and saturated with nitrogen, which are able to deposit the W-N thin film. We also examine the deposition mechanism and the effect of $NH_3$ pulse plasma treatment.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.8
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• pp.91-97
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• 2008

The conventional WF(water-filling)-MIMO systems assumes that the channel state information is perfectly known at receiver. However, since, generally, the perfect channel state information is not available at receiver, channel estimation error should be considered at the system. Therefore, in this paper 4he performance of the conventional WF-MIMO systems is numerically analyzed when channel estimation error is considered. The analysis results show that mean square error of channel estimation up to $10^{-4}$ is tolerable to get the same performance obtained when perfect channel information is available.

• Journal of Life Science
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• v.29 no.7
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• pp.779-784
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• 2019

Free radicals are known to inhibit hair vitality by damaging the cell membranes of the hair follicles. The purpose of this study was to determine the antioxidant activities and the capacity for hair loss prevention of extracts from Platycodon grandiflorum. We prepared butanol (BF) and water (WF) fractions from P. grandiflorum. DPPH and ABTS radical scavenging activities were measured to investigate the antioxidant activities of the fractions. Both fractions exhibited dose-dependent antioxidant activities for DPPH radical production, and BF and WF almost completely suppressed ABTS radical production when supplied at 10 and 100 mg/ml, respectively. We confirmed a skin regeneration effect by treating human HaCaT skin cells with a range of BF and WF concentrations for 24 and 48 hr. The extract treatments accelerated cell proliferation. We also assayed the capacity of BF and WF to suppress inflammation using RAW264.7 cells. BF dose-dependently suppressed nitrous oxide (NO) production. Treatment of human hair follicle dermal papilla cells (HFDPC) with BF and WF promoted cell proliferation after 24, 48, and 72 hr of treatment when supplied at 10, 50, 100, and $200{\mu}g/ml$. Taken together, these results confirm the possibility of using BF and WF extracts from P. grandiflorum in formulating hair loss prevention products.

• Molecules and Cells
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• v.24 no.1
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• pp.125-131
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• 2007

von Willebrand factor (vWF) is a multimeric glycoprotein which functions within the coagulation system. It colocalizes with factor VIII (FVIII) by non-covalent interaction and alters its intracellular trafficking. vWF is also instrumental in maintaining the stability of secreted FVIII. The principal objective of this study was to generate a lentivirus-based vWF expression vector for gene therapy of hemophilia A. We inserted a vWF of 8.8 Kb into a lentiviral vector thereby producing VSV-G-pseudotyped vEx52. However, its titer was quite low, presumably because the length of vWF gene exceeds the size limit of the lentiviral vector. In order to overcome the low-titer, we concentrated the vEx52 and thus increased the efficiency of transduction approximately 6-fold with $1/100^{th}$ of the volume. However, as concentration requires an additional laborious step, we attempted to enhance the transduction efficiency by deleting exons 24-46 and 29-46 in pRex52 to construct pRex23 and pRex28, and in pvEx52, yielding pvEx23 and pvEx28, respectively. The transfected pRex52 had a profound effect on the activity of secreted FVIII, and this activity declined as domains of vWF were deleted. However, when the domain-deleted vWF-lentiviruses were transduced into K562 cells, the vEx28 increased the activity of the secreted FVIII compared to what was observed with vEx52. This result is probably due to higher efficiencies of transduction and expression while retaining the essential domains required for proper interaction with FVIII.