• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.11B
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• pp.900-910
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• 2004

Route failure is mainly caused by mobility of mobile host in ad hoc networks. Route failure, which may lead to sudden packet losses and delays, is losing the route from source to destination. In this situation, TCP assumes that congestion has occurred within the network and also initiates the congestion control procedures. Congestion control algorithm provides the means for the source to deal with lost packets. TCP performance in ad hoc environments will be degraded as TCP source cannot distinguish congestion from route failure. In this paper, we propose TCP-P as pre-detection approach to deal with route failure. TCP-P freezes TCP through pre-detection of route failure. Route failure information of the proposed mechanism is obtained not by routing protocol but by MAC protocol. The intermediated node, obtaining route failure information by its MAC layer, relays the information to TCP source and lets TCP source stop the congestion control algorithm. Results reveal that TCP-P responding with proactive manner outperforms other approaches in terms of communication throughput under the presence of node mobility.

• International Journal of Computer Science & Network Security
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• v.21 no.6
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• pp.1-6
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• 2021

Recently, pre-trained convolutional neural network CNNs have been widely used and applied for medical image classification. These models can utilised in three different ways, for feature extraction, to use the architecture of the pre-trained model and to train some layers while freezing others. In this study, the ResNet18 pre-trained CNNs model is used for feature extraction, followed by the support vector machine for multiple classes to classify medical images from multi-classes, which is used as the main classifier. Our proposed classification method was implemented on Kvasir and PH2 medical image datasets. The overall accuracy was 93.38% and 91.67% for Kvasir and PH2 datasets, respectively. The classification results and performance of our proposed method outperformed some of the related similar methods in this area of study.

• Clinical and Experimental Reproductive Medicine
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• v.45 no.4
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• pp.177-182
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• 2018

Objective: To investigate the effects of in vitro myo-inositol (Myo-Ins) supplementation of cryopreserved human semen on the cryo-survival rate (CSR). Methods: Semen samples were obtained from 41 infertile men. Following routine semen analysis, each sample was divided into two equal aliquots (0.5 mL each). One aliquot was treated with 1 mg of Myo-Ins dissolved in $10{\mu}L$ of sperm preparation medium. The second aliquot was treated with $10{\mu}L$ of the same medium (control). Both aliquots were incubated for 20 minutes prior to freezing to slow the freezing process. The frozen samples were examined for post-thaw percentages of total motility (TM), progressive motility (PM), and the CSR, defined as the percentage of post-thaw TM divided by the percentage of pre-freeze TM and multiplied in 100. The results were expressed as median and interquartile range (25th and 75th percentiles). Results: The pre-freeze TM (50% [30%-50%]) and PM (35% [20%-35%]) were significantly higher than the post-thaw TM and PM in the MyoIns group (15% [10%-35%] and 10% [5%-20%]; p<0.001 and p<0.001, respectively) and the control group (10% [6%-30%] and 5% [3%-15%]; p<0.001 and p<0.001, respectively). The CSR of the 41 semen aliquots supplemented with Myo-Ins (40% [25%-70%]) was significantly higher than that of the control samples (30% [13%-58%], p=0.041). The CSR of the 26 abnormal semen samples that were supplemented with Myo-Ins (38% [20%-50%]) was significantly higher than that of the control samples (23% [12%-30%], p=0.031). Conclusion: In vitro Myo-Ins supplementation of ejaculated human sperm from infertile men resulted in a significant increase in the CSR in samples with abnormal pre-freeze sperm parameters.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.5
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• pp.372-378
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• 2000

The cell culture of Angelica gigas Nakai producing decursin derivatives and immunostimulating polysaccharides was preserved in liquid nitrogen after pre-freezing in a deep freezer at -70$^{\circ}C$ for 480 min. The effects of the cryoprotectant and pretreatment before cooling were investigated to obtain the optimal procedure for cyropreservation. When compared to mannitol, sorbitol, or NaCl with a similar osmotic pressure, 0.7 M sucrose was found to be the best osmoticum for the cryopreservation of A. gigas cells. In the pre-culture medium, the cells in the exponential growth phase showed phase showed the best post-freezing survival after cryopreservation. A mixture of sucrose, glycerol, and DMSO was found to be an effective cryoprotectant and a higher concentration of the cryoprotectant provided better cell viability. When compared with the vitrification, the optimum cryopreservation method proposed in this study would seem to be more effective for the long-term storage of suspension cells. The highest relative cell viability established with the procedure was 89%.

• Animal Bioscience
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• v.36 no.2
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• pp.209-217
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• 2023

Objective: The conservation of Bali bulls, the Indonesian native breed of cattle, is crucial for cattle breeding in Indonesia. To guarantee the spread of Bali bulls through artificial insemination the quality of the frozen semen must be high. To this end, adding an extender material to semen that increases spermatozoa's survival during cryopreservation is important. Green tea extract (GTE) can be used as cryoprotectant because its high antioxidant activity can help avoid reactive oxygen species formation. Methods: Semen of five Bali bulls from the National Artificial Insemination Center at Singosari, Indonesia was collected routinely twice a week. First, fresh semen inspection was performed to determine the feasibility of using Bali bulls as animal samples. The extender used in this study was Tris-based egg yolk. The samples were divided into four treatments: T0, no GTE added to the extender; T1, 0.05 mg GTE plus 100 mL extender; T2, 0.10 mg GTE plus 100 mL extender; and T3, 0.15 mg GTE plus 100 mL extender. The semen freezing process was conducted according to standard procedures and sperm quality parameters, i.e., sperm motility, viability, abnormalities, and membrane integrity observed pre-freezing and post-thawing. Results: There were significant differences in total motility, progressive motility, viability, and integrity membrane of Bali bull sperm at both pre-freezing and post-thawing after adding GTE into the extender. In contrast, there were no differences in abnormalities among treatments. Conclusion: Adding GTE at a 0.15 mg into 100 mL Tris-based egg yolk extender can improve the quality of cryopreserved Bali bull sperm.

• Textile Coloration and Finishing
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• v.21 no.1
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• pp.10-20
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• 2009

The objective of this study is to investigate the efficacy of leaf powder colorants as substitutes for traditional fresh juice extract dyeing. Three kinds of leaf powder colorants were prepared by freeze drying method with or without deep freezing as pre-treatment: one powder colorant from fresh leaf juice with deep freezing; two kinds of powder colorant from fresh leaves with and without deep freezing. Their dyeing properties and storage stabilities were studied and compared with the traditional fresh juice extract dyeing. The presence of indigo in the powder colorants was confirmed by UV/Visible absorption spectra. They showed absorption peak at 602nm which was same with indigo absorption peak. Dyeing was done at low temperature around 6$^{\circ}C$. All three powder colorants produced B colors on silk fabrics, showing similar color to the one dyed traditionally with fresh juice extract. The powder colorants from leaves gave higher color strength than the powder from leaf juice. The powder colorant prepared from leaves with deep freezing was the most stable for long term storage as its color and color strength were not changed after 360 days. So, this was used for further dyeing to study the effects of concentration and repeat dyeing on color strength and colorfastness. Fastnesses to dry cleaning and rubbing were fairly good above 4 rating. Further study is needed to improve light fastness. It was concluded that the leaf powder colorant with deep freezing could be used as a substitute for traditional juice extract dyeing at all seasons.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.813-819
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• 2006

Skid Resistance is a index to represent the friction between tire and road surface, which influences driving safety. Skid resistance varies with the conditions of tire, abrasion of road surface, vehicle speed, drying, wet and freezing condition of road surfaces. Especially, freezing occurs when temperature drops below $0^{\circ}C$ followed by snow or rain causes decrease of skid resistance. To recover the decreased skid resistance deicing work is applied. As a results of deicing works, freezing condition is changed into wet condition. However the wet road surfaces containing the remaining deicings agents may not show the skid resistance of normal wet condition. In this study, skid resistances in the condition of freezing, deicing process and deicing agents remained after snow-removal are evaluated. The test results, skid resistance recover quickly when Pre-wetted salt spreading and NaCl was used as deicing method. Skid resistance of Deicing agents remained on the road surface showed that concrete is higher than asphalt. superior effect. Recovery rate of skid resistance by comparison wet condition is 54~80%.

• Reproductive and Developmental Biology
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• v.32 no.2
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• pp.111-115
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• 2008

The aim of this study was to examine more effective cryoprotectant for the cryopreservation of mouse preantral follicles. Enzymetically isolated preantral follicles from 12-day-old mice were cryopreserved by a slow freezing protocol with 1.5 M propanediol (PROH), dimethyl sulphoxide (DMSO) or glycerol (GLY) and then grown and matured in vitro for 11 days after thawing. The survival of preantral follicles immediately after freezing and thawing was not different among the PROH (68.2%), DMSO (72.4%) and GLY (72.1%). After grown and matured in vitro, the rates of survival and metaphase II oocytes were 54.9% and 36.6% for PROH which was significantly higher rates (p<0.05) compared with the rates obtained from DMSO (16.9% and 9.0%) and GLY (16.3% and 7.5%). The diameter of metaphase II oocytes from pre antral follicles frozen in PROH ($67.4{\pm}1.8\;{\mu}m$) was significantly (p<0.05) smaller than that of the fresh preantral follicles ($69.1{\pm}2.3\;{\mu}m$). The results from the present study revealed that PROH is more suitable cryoprotectant for the cryopreservation of mouse preantral follicles.

• The Korean Journal of Food And Nutrition
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• v.33 no.1
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• pp.1-8
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• 2020

The purpose of this study was to prevent excessive softening of seasoned spinach by heating and freezing through the pre-heating treatment in calcium chloride solution. The pre-heating temperature was set at 60℃, which supports the highest activity of pectinesterase around 60℃. Pre-heating spinach in calcium solution does not affect the chromaticity characteristics of spinach leaves and significantly improves its texture compared to conventional blanching only and pre-heating in water. The improvement of the firmness is related to the formation of strongly cross-linkages between carboxyl groups and Ca²⁺ by the action of the pectinesterase in spinach. For reheated spinach, the firmness of calcium chloride treated stems were 37.80~44.44 kg, and the control was 28.73 kg. The firmness of calcium chloride treated leaves was 19.73~40.79 kg, and the control was 9.63 kg. Additionally, the total aerobic bacteria in the fresh samples were 3.25~3.99 log CFU/g and 1.97~2.72 log CFU/g in the reheated samples. And the total coliform was not detected in the reheated samples. Considering the color, texture, microbial characteristics and taste quality, the optimum pre-treatment conditions to prevent excessive softening of spinach were 3% calcium chloride solution and 15minutes of treatment.

• Animal Bioscience
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• v.35 no.8
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• pp.1270-1278
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• 2022

Objective: The objective of this study was to evaluate quality characteristics of reduced-salt pork sausage (PS) using pre-rigor muscle compared to those of regular-salt PS. In addition, effects of freezing on sausage batter with different temperatures (-30℃ vs -70℃) on quality characteristics of both sausage batter and cooked sausages during frozen storage were observed. Methods: Pre-rigor and post-rigor pork hams were used to manufacture low-fat sausages. Sausages using post-rigor (Post) muscle were manufactured at a salt level of 1.5%, whereas those with pre-rigor (Pre) muscle were processed at salt level of 1.0%. After these muscles were made at two salt levels (1.5% salt, Post-rigor; 1.0% salt, Pre-rigor), Sausage batters were stored at two frozen temperatures (-30℃ vs -70℃). During storage for 12 wks, they were measured for physicochemical and textural properties every 4 wks up to 12 wks. Results: pH values and temperatures of sausage batter of pre-rigor muscle were higher than those of post-rigor muscle regardless of the frozen temperature. The lightness and yellowness values of batter at the initial storage were the highest during storage. For PS, there were no differences in most parameters measured among all treatments. However, expressible moisture values (%) of Pre-30 and Pre-70 were lower than those of Post-30 (p<0.05). Conclusion: Regardless of frozen temperature during storage, quality characteristics of pre-rigor PS with salt level of 1.0% salt were similar to those of post-rigor PS with salt level of 1.5%. By using the pre-rigor muscle, salt content could be reduced by one third of the regular-salt level (1.5%) of post-rigor muscle.