• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.7
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• pp.569-572
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• 2003

In this study, we evaluated the dilute HF cleaning to reduce residual defects made by metal CMP process. The purpose of this test is to observe the existence of barrier metal damage during DHF cleaning on condition that it should not affect metal thin film reliability, so we will get rid of slurry residual particles as a main defect of the metal CMP process for the better yield. In-line defect data showed us that slurry residual particles were removed by DHF application. The HF rinse significantly reduced metal contamination levels and surface roughness. The best effect by additional oxide loss was discovered when Dilute HF condition is 10".

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.2
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• pp.52-62
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• 2013

Design Hourly Factor(DHF) is defined as the ratio of design hourly volume(DHV) to Average Annual Daily Traffic(AADT). Generally DHV used the 30th rank hourly volume. But this case DHV is affected by holiday volumes so the road is at risk for overdesigning. Computing K factor is available for counting 8,760 hour traffic volume, but it is impossible except permanent traffic counts. This study applied three method to make DHF, using 30th rank hourly volume to make DHF(method 1), using peak hour volume to make DHF(method 2). Another way to make DHF, rank hourly volumes ordered descending connect a curve smoothly to find the point which changes drastic(method 3). That point is design hour, thus design hourly factor is able to be computed. In addition road classified 3 type for national highway using factor analysis and cluster analysis, so we can analyze the characteristic of DHF by road type. DHF which was used method 1 is the largest at any other method. There is no difference in DHF by road type at method 2. This result shows for this reason because peak hour is hard to describe the characteristic of hourly volume change. DHF which was used method 3 is similar to HCM except recreation road but 118th rank hourly volume is appropriate.

• Journal of the Korean Applied Science and Technology
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• v.16 no.1
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• pp.33-40
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• 1999

We used Cu as a representative of metals to be directly adsorbed on the bare Si surface and studied its removal DHF, DHF-$H_2O_2$ and BHF solution. It has been found that Cu ion in DHF adheres on every Si wafer surface that we used in our study (n, p, n+, p+) especially on the n+-Si surface. The DHF-$H_2O_2$ solution is found to be effective in removing metals featuring high electronegativity such as Cu from the p-Si and n-Si wafers. Even when the DHF-$H_2O_2$ solution has Cu ions at the concentration of 1ppm, the solution is found effective in cleaning the wafer. In the case the n+-Si and p+-Si wafers, however, their surfaces get contaminated with Cu When Cu ion of 10ppb remains in the DHF-$H_2O_2$ solution. When BHF is used, Cu in BHF is more likely to contaminate the n+-Si wafer. It is also revealed that the surfactant added to BHF improve wettability onto p-Si, n-Si and p+-Si wafer surface. This effect of the surfactant, however, is not observed on the n+-Si wafer and is increased when it is immersed in the DHF-$H_2O_2$ solution for 10min. The rate of the metallic contamination on the n+-Si wafer is found to be much higher than on the other Si wafers. In order to suppress the metallic contamination on every type of Si surface below 1010atoms/cm2, the metallic concentration in ultra pure water and high-purity DHF which is employed at the final stage of the cleaning process must be lowered below the part per trillion level. The DHF-$H_2O_2$ solution, however, degrades surface roughness on the substrate with the n+ and p+ surfaces. In order to remove metallic impurities on these surfaces, there is no choice at present but to use the $NH_4OH-H_2O_2-H_2O$ and $HCl-H_2O_2-H_2O$ cleaning.

• Biomolecules & Therapeutics
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• v.27 no.1
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• pp.85-91
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• 2019

Oxidative stress is considered a major contributor in the pathogenesis of diabetic neuropathy and in diabetes complications, such as nephropathy and cardiovascular diseases. Diabetic neuropathy, which is the most frequent complications of diabetes, affect sensory, motor, and autonomic nerves. This study aimed to investigate whether 7,8-dihydroxyflavone (7,8-DHF) protects SH-SY5Y neuronal cells against high glucose-induced toxicity. In the current study, we found that diabetic patients exhibited higher lipid peroxidation caused by oxidative stress than healthy subjects. 7,8-DHF exhibits superoxide anion and hydroxyl radical scavenging activities. High glucose-induced toxicity severely damaged SH-SY5Y neuronal cells, causing mitochondrial depolarization; however, 7,8-DHF recovered mitochondrial polarization. Furthermore, 7,8-DHF effectively modulated the expression of pro-apoptotic protein (Bax) and anti-apoptotic protein (Bcl-2) under high glucose, thus inhibiting the activation of caspase signaling pathways. These results indicate that 7,8-DHF has antioxidant effects and protects cells from apoptotic cell death induced by high glucose. Thus, 7,8-DHF may be developed into a promising candidate for the treatment of diabetic neuropathy.

• International Journal of Stem Cells
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• v.15 no.3
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• pp.334-345
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• 2022

Background and Objectives: Flavonoids form the largest group of plant phenols and have various biological and pharmacological activities. In this study, we investigated the effect of a flavonoid, 3, 4'-dihydroxyflavone (3, 4'-DHF) on osteogenic differentiation of equine adipose-derived stromal cells (eADSCs). Methods and Results: Treatment of 3, 4'-DHF led to increased osteogenic differentiation of eADSCs by increasing phosphorylation of ERK and modulating Reactive Oxygen Species (ROS) generation. Although PD98059, an ERK inhibitor, suppressed osteogenic differentiation, another ERK inhibitor, U0126, apparently increased osteogenic differentiation of the 3, 4'-DHF-treated eADSCs, which may indicate that the effect of U0126 on bone morphogenetic protein signaling is involved in the regulation of 3, 4'-DHF in osteogenic differentiation of eADSCs. We revealed that 3, 4'-DHF could induce osteogenic differentiation of eADSCs by suppressing ROS generation and co-treatment of 3, 4'-DHF, U0126, and/or N-acetyl cysteine (NAC) resulted in the additive enhancement of osteogenic differentiation of eADSCs. Conclusions: Our results showed that co-treatment of 3, 4'-DHF, U0126, and/or NAC cumulatively regulated osteogenesis in eADSCs, suggesting that 3, 4'-DHF, a flavonoid, can provide a novel approach to the treatment of osteoporosis and can provide potential therapeutic applications in therapeutics and regenerative medicine for human and companion animals.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.362-367
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• 1997

To assess the coolability of particle bed, which is formed in reactor cavity, it is important to assess the prediction capabilities of Dryout Heat flux correlations. The existing DHF correlations (Sowa et al., Dhir-Catton (a), Dhir-Catton (b), Hardee-Nilson, Ostesen, Shires-Stevens, Lipinski, Jones et al., Dhir-Barleon, Theofanous-Saito, Henry-Fauske) for particle beds are assessed using developed DHF database. Eleven DHF correlations are chosen for assessment based on literature survey. Among them, five are based on flooding correlation, which are used for chemical engineering and others are based on conservation equations. The parameters in DHF correlations are directly substituted into correlations. Totally 202 data are classified into 6 groups based on bed thickness and particle diameter. In each group, prediction capabilities of correlations are assessed and shown by standard deviation and root mean square (RMS) error. Prediction capability of each correlation depends on the data group and none of correlations shows best prediction capability on entire groups. According to present study, even if those correlations show poor prediction capability, Lipinski correlation is best correlation considering entire groups.

• Clinics in Shoulder and Elbow
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• v.25 no.2
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• pp.163-169
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• 2022

Distal humerus fractures (DHFs) are challenging to treat due to the locally complex osseous and soft tissue anatomy. Adequate exposure of the articular surface of the distal humerus is crucial when performing an anatomical reconstruction of the elbow. Even though "triceps-on" approaches are gaining popularity, one of the most commonly used surgical treatments for DHF is olecranon osteotomy. The incidence of complications related to this approach is unclear. This review was performed to assess the type and frequency of complications that occur with the olecranon osteotomy approach in the treatment of DHF. A literature search was conducted in the PubMed/Medline, Embase, and Cochrane Library digital databases up to February 2020. Only English articles describing complications of olecranon osteotomy in the treatment of DHF were included. Data on patient and surgical characteristics and complications were extracted. Statistical analysis was performed using SPSS. A total of 41 articles describing 1,700 osteotomies were included, and a total of 447 complications were reported. Of these 447 complications, wound infections occurred in 4.2% of osteotomies, of which 1.4% were deep infections and 2.8% were superficial. Problems related with union occurred in 3.7% of osteotomies, 2% of which represented non-union and 1.7% delayed union. The high risk of complications in olecranon osteotomy must be considered in the decision to perform this procedure in the treatment of DHF.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.147-150
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• 2002

In this study, we evaluated the dilute HF Cleaning to reduce residual defects made by W CMP process. But, One point we should focus is It should not effect to metal thin film reliability. The purpose of this test is to verify barrier metal damage during HF cleaning and based on this result we get rid of slurry residue defect which is main defect of W CMP process for the better yield.

• Nuclear Engineering and Technology
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• v.56 no.2
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• pp.636-643
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• 2024

The coolability of the debris bed with a simulant of solidified corium is experimentally studied, focusing on the effects of the structure of the axial stratified debris bed on the dryout heat flux (DHF). DHF was obtained for the four structures with different particle sizes for the axial stratified debris bed under top flooding. The experimental results show that the dryout position of the axial stratified debris bed is formed at the stratified interface indicated by the temperature rise, and the DHF of the axial stratified bed is much lower than that of the homogeneous bed packed with the upper small particles. To predict the dryout heat flux of the stratified debris beds, by considering the properties of the mixed area, a one-dimensional dryout heat flux model of the porous medium is derived from a water and vapor momentum equation for porous medium, two-phase permeability modifications, interfacial drag, and the correlation between capillary pressure and liquid saturation and verified with the experimental data. The modified model can give reasonable results under different structures.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.562-568
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• 2017

Objective: The hull attached to the barley kernel can be mechanically removed thus reducing the fiber content of the barley. This experiment was carried out to evaluate the effects of partial dehulling on the nutrient digestibility as well as the digestible energy (DE) and metabolizable energy (ME) content of barley in pigs. Methods: Two hulled barley samples (high fiber barley [HF] and low fiber barley [LF]) with either high or low fiber contents were obtained from the Hubei and Jiangsu Provinces of China. A portion of the two barleys was mechanically dehulled (dehulled high fiber barley [DHF] and dehulled low fiber barley [DLF]). Thirty barrows (initial $BW=31.5{\pm}3.2kg$) were assigned to one of five diets in a randomized complete block design. The five diets consisted of 96.9% corn, HF, LF, DHF, or DLF supplemented with 3.1% minerals and vitamins. Each diet was fed to six barrows housed in individual metabolism crates for a 10-d acclimation period followed by a 5-day total but separate collection of feces and urine. Results: The daily loss of gross energy (GE) in feces was lower (p<0.01) for pigs fed DHF than for those fed HF. The daily N intake and fecal N loss were lowest (p<0.01) for pigs fed the corn diet. The DE and ME as well as the apparent total tract digestibility (ATTD) of dry matter, GE, organic matter, neutral detergent fiber (NDF) and acid detergent fiber (ADF) of DHF or DLF were higher (p<0.01) than the values in HF and LF, respectively while the values except the ATTD of NDF and ADF in DLF were higher (p<0.01) than the values in DHF and were comparable to corn. Conclusion: The DE and ME contents as well as the ATTD of nutrients in both DHF and DLF barley were improved compared with the HF and LF barley. Moreover, the nutritive value of DLF barley was comparable to the yellow-dent corn used in the study.