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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation
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作者 Xu Liang Ni-Hui Zhang +4 位作者 Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao 《Traditional Medicine Research》 2025年第2期1-15,共15页
Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants h... Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants have some differences in efficacy,but the flower buds are easily confused for similar traits.In addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal roses.Therefore,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography fingerprints.Then,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large differences.Differential compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and Meigui.Results:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the samples.Through principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four groups.Partial least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavonoid glycosides,as well as phenolic acids.Eight differential components were screened out by orthogonal partial least-squares discriminant analysis and S-plot analysis.Quantitative analyses of the eight compounds,including gallic acid,ellagic acid,hyperoside,isoquercitrin,etc.,showed that Yueji was generally richer in phenolic acids and flavonoids than Meigui,and the quality of Yueji from Shandong and Hebei was better.It is worth noting that Xinjiang rose is rich in various components,which is worth focusing on more in-depth research.Conclusion:In this study,the fingerprints of Meigui and Yueji were established.The chemical components information of roses was further improved based on non-targeted metabolomics and mass spectrometry technology.At the same time,eight differential components of Meigui and Yueji were screened out and quantitatively analyzed.The research results provided a scientific basis for the quality control and rational development and utilization of Rosae Chinensis Flos and Rosae Rugosae Flos,and also laid a foundation for the study of their pharmacodynamic material basis. 展开更多
关键词 Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics CHEMOMETRICS multiple component quantification quality evaluation
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Effects of increased seeding density on seedling characteristics,mechanical transplantation quality,and yields of rice with crop straw boards for seedling cultivation
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作者 Yufei Ling Mengzhu Liu +5 位作者 Yuan Feng Zhipeng Xing Hui Gao Haiyan Wei Qun Hu Hongcheng Zhang 《Journal of Integrative Agriculture》 2025年第1期101-113,共13页
The high labor demand during rice seedling cultivation and transplantation poses a significant challenge in advancing machine-transplanted rice cultivation.This problem may be solved by increasing the seeding rate dur... The high labor demand during rice seedling cultivation and transplantation poses a significant challenge in advancing machine-transplanted rice cultivation.This problem may be solved by increasing the seeding rate during seedling production while reducing the number of seedling trays.This study conducted field experiments from 2021 to 2022,using transplanting seedling ages of 10 and 15 days to explore the effects of 250,300,and 350 g/tray on the seedling quality,mechanical transplantation quality,yields,and economic benefits of rice.The commonly used combination of 150 g/tray with a 20-day seedling age in rice production was used as CK.The cultivation of seedlings under a high seeding rate and short seedling age significantly affected seedling characteristics,but there was no significant difference in seedling vitality compared to CK.The minimum number of rice trays used in the experiment was observed in the treatment of 350-10(300 g/tray and 10-day seedling age),only 152-155 trays ha^(-1),resulting in a 62%reduction in the number of trays needed.By increasing the seeding rate of rice,missed holes during mechanical transplantation decreased by 2.8 to 4%.The treatment of 300-15(300 g/tray and 15-day seedling age)achieved the highest yields and economic gains.These results indicated that using crop straw boards can reduce the application of seedling trays.On that basis,rice yields can be increased by raising the seeding rate and shortening the seedling age of rice without compromising seedling quality. 展开更多
关键词 machine-transplanted rice crop straw board seedling rate seedling quality mechanical transplanta quality yield
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Application of Fructo-oligosaccharides Quality Control Chart in Milk Powder
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作者 Guoxia DUAN Lijun LIU +5 位作者 Ruilong XIE Xue HU Lunwei WU Jing CHEN Huili GONG Chunxia LIU 《Asian Agricultural Research》 2025年第1期35-37,共3页
The quality control chart of fructo-oligosaccharides in milk powder was established to determine whether the detection process and results are in control state.The content of fructo-oligosaccharides in milk powder con... The quality control chart of fructo-oligosaccharides in milk powder was established to determine whether the detection process and results are in control state.The content of fructo-oligosaccharides in milk powder control samples was determined by ion chromatography,and the quality control chart of fructo-oligosaccharides was established to analyze the controlled state.The results indicate that the median of the quality control chart is 1613.14 mg/100 g,and the standard deviation is 85.57 mg/100 g.The new quality control points were evaluated and analyzed,and the precision changed,but the mean value did not change.Further F test was conducted to determine that the precision did not change significantly,indicating that the test was in a statistical control state,and the detection process,method and results were controlled. 展开更多
关键词 quality control chart FRUCTO-OLIGOSACCHARIDES Milk powder
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The chemical composition, quality control and pharmacological effects of Gualou-Xiebai-Banxia Decoction: a review
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作者 Yan-Tao Wang Yin-Yan Lai +4 位作者 Li Wang Xiao-Li Zheng Hong-Ju Li Su-Hong Chen Zheng Xiang 《Traditional Medicine Research》 2025年第4期72-82,共11页
Gualou-Xiebai-Banxia Decoction(GXBD)is a traditional Chinese herbal formula including four traditional Chinese medicines:Gualou(Trichosanthis Fructus,TF),Xiebai(Allii Macrostemonis Bulbus,AMB),Banxia(Pinelliae Rhizoma... Gualou-Xiebai-Banxia Decoction(GXBD)is a traditional Chinese herbal formula including four traditional Chinese medicines:Gualou(Trichosanthis Fructus,TF),Xiebai(Allii Macrostemonis Bulbus,AMB),Banxia(Pinelliae Rhizoma,PR)and yellow wine.It is a classical therapy for chest stuffiness and pain syndrome and is widely used in the clinical treatment of coronary heart disease.It also shows significant therapeutic effects on pulmonary heart disease,hyperlipidemia,and arrhythmia.This study conducted a literature review and collected information on GXBD from databases such as PubMed,Web of Science,China National Knowledge Infrastructure,and ScienceDirect.The result indicated that the main active ingredients of GXBD are steroids,flavonoids,terpenoids,alkaloids,amino acids,and organic acids.Trigonelline,macrostemonoside and cucurbitacin B can provide reference for its quality control.GXBD may exert therapeutic effects on coronary heart disease through AMPK,PI3K-AKT,oxLDL,VEGF,and NF-κB signal pathways.This review provides a comprehensive analysis and summary of the chemical composition and in vivo metabolism of three traditional Chinese medicines(TF,AMB,and PR),along with an evaluation of the chemical composition,quality control,pharmacological effects,and clinical application of GXBD.Based on these,areas requiring further research on GXBD have been proposed to provide a reference for its further development and new drug research. 展开更多
关键词 Gualou-Xiebai-Banxia Decoction chemical composition chest stuffiness quality control pharmacological mechanism
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Genomic selection for meat quality traits based on VIS/NIR spectral information
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作者 Xi Tang Lei Xie +8 位作者 Min Yan Longyun Li Tianxiong Yao Siyi Liu Wenwu Xu Shijun Xiao Nengshui Ding Zhiyan Zhang Lusheng Huang 《Journal of Integrative Agriculture》 2025年第1期235-245,共11页
The principle of genomic selection(GS) entails estimating breeding values(BVs) by summing all the SNP polygenic effects. The visible/near-infrared spectroscopy(VIS/NIRS) wavelength and abundance values can directly re... The principle of genomic selection(GS) entails estimating breeding values(BVs) by summing all the SNP polygenic effects. The visible/near-infrared spectroscopy(VIS/NIRS) wavelength and abundance values can directly reflect the concentrations of chemical substances, and the measurement of meat traits by VIS/NIRS is similar to the processing of genomic selection data by summing all ‘polygenic effects' associated with spectral feature peaks. Therefore, it is meaningful to investigate the incorporation of VIS/NIRS information into GS models to establish an efficient and low-cost breeding model. In this study, we measured 6 meat quality traits in 359Duroc×Landrace×Yorkshire pigs from Guangxi Zhuang Autonomous Region, China, and genotyped them with high-density SNP chips. According to the completeness of the information for the target population, we proposed 4breeding strategies applied to different scenarios: Ⅰ, only spectral and genotypic data exist for the target population;Ⅱ, only spectral data exist for the target population;Ⅲ, only spectral and genotypic data but with different prediction processes exist for the target population;and Ⅳ, only spectral and phenotypic data exist for the target population.The 4 scenarios were used to evaluate the genomic estimated breeding value(GEBV) accuracy by increasing the VIS/NIR spectral information. In the results of the 5-fold cross-validation, the genetic algorithm showed remarkable potential for preselection of feature wavelengths. The breeding efficiency of Strategies Ⅱ, Ⅲ, and Ⅳ was superior to that of traditional GS for most traits, and the GEBV prediction accuracy was improved by 32.2, 40.8 and 15.5%, respectively on average. Among them, the prediction accuracy of Strategy Ⅱ for fat(%) even improved by 50.7% compared to traditional GS. The GEBV prediction accuracy of Strategy Ⅰ was nearly identical to that of traditional GS, and the fluctuation range was less than 7%. Moreover, the breeding cost of the 4 strategies was lower than that of traditional GS methods, with Strategy Ⅳ being the lowest as it did not require genotyping.Our findings demonstrate that GS methods based on VIS/NIRS data have significant predictive potential and are worthy of further research to provide a valuable reference for the development of effective and affordable breeding strategies. 展开更多
关键词 VIS/NIR genomic selection GEBV machine learning PIG meat quality
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Assessing the data quality and seismic monitoring capabilities of the Belt and Road GNSS network
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作者 Yu Li Yinxing Shao +2 位作者 Tan Wang Yuebing Wang Hongbo Shi 《Earthquake Science》 2025年第1期56-66,共11页
The Belt and Road global navigation satellite system(B&R GNSS)network is the first large-scale deployment of Chinese GNSS equipment in a seismic system.Prior to this,there have been few systematic assessments of t... The Belt and Road global navigation satellite system(B&R GNSS)network is the first large-scale deployment of Chinese GNSS equipment in a seismic system.Prior to this,there have been few systematic assessments of the data quality of Chinese GNSS equipment.In this study,data from four representative GNSS sites in different regions of China were analyzed using the G-Nut/Anubis software package.Four main indicators(data integrity rate,data validity ratio,multi-path error,and cycle slip ratio)used to systematically analyze data quality,while evaluating the seismic monitoring capabilities of the network based on earthquake magnitudes estimated from high-frequency GNSS data are evaluated by estimating magnitude based on highfrequency GNSS data.The results indicate that the quality of the data produced by the three types of Chinese receivers used in the network meets the needs of earthquake monitoring and the new seismic industry standards,which provide a reference for the selection of equipment for future new projects.After the B&R GNSS network was established,the seismic monitoring capability for earthquakes with magnitudes greater than M_(W)6.5 in most parts of the Sichuan-Yunnan region improved by approximately 20%.In key areas such as the Sichuan-Yunnan Rhomboid Block,the monitoring capability increased by more than 25%,which has greatly improved the effectiveness of regional comprehensive earthquake management. 展开更多
关键词 Belt and Road multi-system GNSS data quality seismic monitoring capability
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面向SDN的QoS优化:一种蚁群算法改进策略的设计与实现
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作者 朱殊 《微型计算机》 2025年第2期16-18,共3页
服务质量(QoS)优化作为提升网络性能的关键手段,在SDN中的应用尤为重要。蚁群算法作为一种启发式的计算方法,由于其出色的全局搜索和并行处理特性,在QoS优化领域显示出了巨大的应用潜力。但是蚁群算法面对SDN动态网络环境、大规模网络... 服务质量(QoS)优化作为提升网络性能的关键手段,在SDN中的应用尤为重要。蚁群算法作为一种启发式的计算方法,由于其出色的全局搜索和并行处理特性,在QoS优化领域显示出了巨大的应用潜力。但是蚁群算法面对SDN动态网络环境、大规模网络、多目标优化及实时性需求,还面临着适应性、收敛速度、平衡性及实时性方面的挑战。该文针对以上问题提出蚁群算法改进策略,通过设计和实施措施改善SDN环境中蚁群算法QoS优化性能。 展开更多
关键词 软件定义网络(SDN) 服务质量(qos) 蚁群算法
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SlPGR5/SlPGRL1 pathway-dependent cyclic electron transport regulates photoprotection and chloroplast quality in tomato plants
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作者 Xiaolong Yang Yumeng Zhang +5 位作者 Ting Liu Jiali Shi Mingfang Qi Riyuan Chen Yufeng Liu Tianlai Li 《Horticultural Plant Journal》 2025年第1期211-226,共16页
The essential photoprotective role of proton gradient regulation 5(PGR5)-dependent cyclic electron flow(CEF)has been reported in Arabidopsis,rice,and algae.However,its functional assessment has not been performed in t... The essential photoprotective role of proton gradient regulation 5(PGR5)-dependent cyclic electron flow(CEF)has been reported in Arabidopsis,rice,and algae.However,its functional assessment has not been performed in tomato yet.In this study,we focused on elucidate the function of SlPGR5 and SlPGR5-like photosynthetic phenotype 1(PGRL1)in tomato.We performed RNA interference and found that SlPGR5/SlPGRL1-suppressed transformants exhibited extremely low CO_(2)assimilation capacity,their photosystem I(PSI)and PSII were severely photoinhibited and chloroplasts were obviously damaged.The SlPGR5/SlPGRL1-suppressed plants almost completely inhibited CEF and Y(ND),and PSII photoinhibition may be directly related to the inability to produce sufficient proton motive force to induce NPQ.The transgenic plants overexpressing SlPGR5 and SlPGRL1 driven by 35S promoter capable alleviate photoinhibition of plants under low night temperature.The transcriptomic and proteomic analyses suggested that the nuclear gene transcription and turnover of chloroplast proteins,including the plastoglobule-related proteins,were closely related to SlPGR5/SlPGRL1 pathway dependent CEF.The bridge relationship between CEF and chloroplast quality maintenance was a novel report to our knowledge.In conclusion,these results revealed the regulatory mechanism of the SlPGR5/SlPGRL1 pathway in photoprotection and maintenance of chloroplast function in tomato,which is crucial for reduce yield loss,especially under adverse environmental conditions. 展开更多
关键词 TOMATO Cyclic electron transport SlPGR5/SlPGRL1 PHOTOPROTECTION Chloroplast quality Plastoglobulus
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Ecological security pattern construction using landscape ecological quality:A case study of Yanchi County,northern China
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作者 LI Junhao WANG Ya +4 位作者 SHI Gui PEI Xiaodong ZHANG Cong ZHOU Lihua YANG Guojing 《Journal of Arid Land》 2025年第1期19-42,共24页
Ecological security patterns are paramount to the advancement of an ecological civilization in China,aiming to enhance the stability and service functions of ecosystems to achieve sustainable regional development.Howe... Ecological security patterns are paramount to the advancement of an ecological civilization in China,aiming to enhance the stability and service functions of ecosystems to achieve sustainable regional development.However,current regional ecological protection efforts have not been effectively integrated into the regional development planning of ecological security pattern.This study systematically assessed the effectiveness of ecological protection projects in Yanchi County,Ningxia Hui Autonomous Region,China,through the evaluation of landscape ecological quality.Based on the evaluation results of landscape ecological quality,this study used morphological pattern analysis(MSPA),minimum cumulative resistance(MCR)model,and gravity model together to construct the ecological security pattern of Yanchi County.The findings revealed that from 1990 to 2020,with the implementation of ecological protection projects started from 2000,the landscape stability of Yanchi County first decreased and then increased,and the intensity of landscape disturbance first intensified but then decreased,indicating an improvement in the landscape ecological quality and a significant enhancement of the ecological environment in Yanchi County.The ecological security pattern of Yanchi County consisted of 10 ecological sources,10 ecological source points,23 ecological corridors,and 27 ecological nodes.The ecological security pattern of Yanchi County exhibited distinct spatial variations,with stronger ecological security observed in the southern part than in northern part of the county.The ecological sources were denser in the southern part than in the northern part of the county,and accordingly,the length of ecological corridors was shorter and denser in the southern than that in the northern part of the county.Based on the spatial distribution of landscape ecological quality and the characteristics of ecological security pattern of Yanchi County in 2020,we suggested Yanchi County to build four zones to optimize the ecological security pattern construction:the Haba Lake ecological conservation zone,the urban ecological planning zone,the ecological environment restoration zone,and the ecological security improvement zone.This study can provide essential guidance for the construction of ecological security pattern in farming-pastoral areas both in China and worldwide. 展开更多
关键词 landscape ecological quality landscape stability landscape disturbance ecological network ecological source ecological corridor farming-pastoral area
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Correlation between psychological,family social support,and home nursing quality for an implanted venous access port
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作者 Heng-Ya Jia Li-Qun Yan +1 位作者 Xiao-Bei Liu Jie Cao 《World Journal of Psychiatry》 2025年第2期130-139,共10页
BACKGROUND Cancer patients with an implanted venous access port(IVAP)often manage their care at home during chemotherapy intervals,including maintaining the device,monitoring complications,and following medication ins... BACKGROUND Cancer patients with an implanted venous access port(IVAP)often manage their care at home during chemotherapy intervals,including maintaining the device,monitoring complications,and following medication instructions.Home care ensures continued support after discharge.However,due to factors such as age,gender,culture,psychological status,and family support,the quality of home care varies significantly.Understanding these factors can help provide targeted guidance to improve the care of cancer patients.AIM To explore IVAP chemotherapy on home care quality and its association with mental health and family support for cancer patients.METHODS This investigative study was based on a medical records system.It investigated the relationship between psychological status,family support,and home care quality in 180 patients with cancer undergoing IVAP chemotherapy.Psychological status was assessed using the State Anxiety Inventory(S-AI);family support was assessed using the Perceived Social Support Scale(PSSS),and home care quality was evaluated using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire(EORTC QLQ-C30).Pearson’s correlation and Structural Equation Modeling were used to analyze the interplay between these factors.RESULTS The average S-AI score was 47.52±14.47,PSSS was 52.48±12.64,and EORTC QLQ-C30 was 70.09±17.32.A substantial inverse relationship was observed between the EORTC QLQ-C30 and S-AI scores(r=-0.712).A significant positive correlation was found between the EORTC QLQ-C30 and the PSSS,with a correlation coefficient of(r=0.744).The multiple linear regression analysis indicated that family social support,psychological status,and average monthly family income were the main factors influencing the variation in the quality of home care,explaining 71.9%of the variation.The Structural Equation Modeling results indicated that psychological status acted as a partial mediator in the association between family social support and home care quality of life,explaining 32.78%of the mediation effect.CONCLUSION Psychological status and family social support positively impacted cancer patients’home care quality,with psychology partially mediating this effect. 展开更多
关键词 Implanted venous access port Cancer patient Home nursing life quality Family social support Psychological status
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Distressing symptoms and health-related quality of life in patients with chronic kidney disease
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作者 Maysoon Abdalrahim Manal Al-Sutari 《World Journal of Nephrology》 2025年第1期119-126,共8页
BACKGROUND Chronic kidney disease(CKD)is an incapacitating illness associated with distressing symptoms(DS)that have negative impact on patients’health-related quality of life(HRQOL).AIM To assess the severity of DS ... BACKGROUND Chronic kidney disease(CKD)is an incapacitating illness associated with distressing symptoms(DS)that have negative impact on patients’health-related quality of life(HRQOL).AIM To assess the severity of DS and their relationships with HRQOL among patients with CKD in Jordan.METHODS A descriptive cross-sectional design was used.A convenience sampling approach was used to recruit the participants.Patients with CKD(n=140)who visited the outpatient clinics in four hospitals in Amman between November 2021 and December 2021 were included.RESULTS The Edmonton Symptom Assessment System was used to measure the severity of the DS while the Short Form-36 tool was used to measure the HRQOL.Participants’mean age was 50.9(SD=15.14).Most of them were males(n=92,65.7%),married(n=95,67.9%),and unemployed(n=93,66.4%).The highest DS were tiredness(mean=4.68,SD=2.98)and worse well-being(mean=3.69,SD=2.43).The highest HRQOL mean score was for the bodily pain scale with a mean score of 68.50 out of 100(SD=32.02)followed by the emotional well-being scale with mean score of 67.60(SD=18.57).CONCLUSION Patients with CKD had suboptimal HRQOL,physically and mentally.They suffer from multiple DS that have a strong association with diminished HRQOL such as tiredness and depression.Therefore,healthcare providers should be equipped with the essential knowledge and skills to promote individualized strategies that focusing on symptom management. 展开更多
关键词 Kidney disease Distressing symptoms quality of life Physical component summary Mental component summary PAIN mental well-being
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Critical quality indicators of high-performance polyetherimide(ULTEM)over the MEX 3D printing key generic control parameters:Prospects for personalized equipment in the defense industry
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作者 Nectarios Vidakis Markos Petousis +6 位作者 Constantine David Nektarios K.Nasikas Dimitrios Sagris Nikolaos Mountakis Mariza Spiridaki Amalia Moutsopoulou Emmanuel Stratakis 《Defence Technology(防务技术)》 2025年第1期150-167,共18页
Additive Manufacturing(AM)can provide customized parts that conventional techniques fail to deliver.One important parameter in AM is the quality of the parts,as a result of the material extrusion 3D printing(3D-P)proc... Additive Manufacturing(AM)can provide customized parts that conventional techniques fail to deliver.One important parameter in AM is the quality of the parts,as a result of the material extrusion 3D printing(3D-P)procedure.This can be very important in defense-related applications,where optimum performance needs to be guaranteed.The quality of the Polyetherimide 3D-P specimens was examined by considering six control parameters,namely,infill percentage,layer height,deposition angle,travel speed,nozzle,and bed temperature.The quality indicators were the root mean square(Rq)and average(Ra)roughness,porosity,and the actual to nominal dimensional deviation.The examination was performed with optical profilometry,optical microscopy,and micro-computed tomography scanning.The Taguchi design of experiments was applied,with twenty-five runs,five levels for each control parameter,on five replicas.Two additional confirmation runs were conducted,to ensure reliability.Prediction equations were constructed to express the quality indicators in terms of the control parameters.Three modeling approaches were applied to the experimental data,to compare their efficiency,i.e.,Linear Regression Model(LRM),Reduced Quadratic Regression Model,and Quadratic Regression Model(QRM).QRM was the most accurate one,still the differences were not high even considering the simpler LRM model. 展开更多
关键词 Polyetherimide(PEI) Material extrusion(MEX) Three-dimensional printing(3D-P) Critical quality indicators(CQIs) Quadratic regression model(QRM) Taguchi
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基于软件定义车载网络的QoS 路由规划研究
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作者 崔峻玮 翟亚红 《汽车技术》 北大核心 2025年第1期26-32,共7页
为了提高车载网络中的数据传输速率和保障业务的QoS需求,结合软件定义车载网络(SDVN)技术,设计了一种基于SDVN的深度强化学习QoS路由算法。该算法可以实现智能化控制和优化管理车载网络中的数据传输,以保证车载网络流量的控制、分配和监... 为了提高车载网络中的数据传输速率和保障业务的QoS需求,结合软件定义车载网络(SDVN)技术,设计了一种基于SDVN的深度强化学习QoS路由算法。该算法可以实现智能化控制和优化管理车载网络中的数据传输,以保证车载网络流量的控制、分配和监控,提高车载数据传输质量和效率。试验结果表明,该路由算法能较好地降低车载网络的时延,与传统路由算法相比,该算法具有更好的优化性能。 展开更多
关键词 软件定义车载网络 服务质量 路由规划 深度强化学习
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共享制造环境下基于Z-RIM的QoS多方异质评价方法
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作者 刘明明 袁琦 禹春霞 《工业工程》 2024年第1期155-164,共10页
为解决共享制造环境下决策信息异质、候选服务数量动态变化的制造服务QoS评价问题,基于平台、服务需求方、服务提供方的三方决策信息,提出一种符合共享制造特点的QoS多方异质制造服务评价方法。通过精确数、语言变量和Z-number处理异质... 为解决共享制造环境下决策信息异质、候选服务数量动态变化的制造服务QoS评价问题,基于平台、服务需求方、服务提供方的三方决策信息,提出一种符合共享制造特点的QoS多方异质制造服务评价方法。通过精确数、语言变量和Z-number处理异质信息;基于共识最大化计算决策方权重向量,利用TrFWAA算子集结多方信息,依据离差最大化模型计算属性权重;在此基础上,采用RIM对各服务进行评估。结合共享制造环境下的制造业服务优选案例对提出的方法进行验证分析,结果表明该方法具有较好的实用性和优越性。 展开更多
关键词 共享制造 Z-number理论 参考理想法(RIM) 群决策 qos评价
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基于SDN的卫星网络端到端QoS类映射研究
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作者 魏德宾 李婧 潘成胜 《计算机仿真》 2024年第7期55-60,共6页
针对在多个卫星网络域环境下域间协作困难,以及如何在各个卫星网络域内选择合适的QoS类实现端到端QoS类映射的问题,基于软件定义卫星网络架构,首先,提出一种SDN卫星网络域间通信方案,以及面向多QoS类的端到端服务交付数据包处理方法。其... 针对在多个卫星网络域环境下域间协作困难,以及如何在各个卫星网络域内选择合适的QoS类实现端到端QoS类映射的问题,基于软件定义卫星网络架构,首先,提出一种SDN卫星网络域间通信方案,以及面向多QoS类的端到端服务交付数据包处理方法。其次,提出一种基于多准则决策的控制模块。模块利用ELECTRE方法,在ELECTRE方法中通过综合权重法计算出各个卫星网络域内QoS指标相应的权重系数,并且利用ELECTRE方法对每个QoS类的净支配指数进行排序,从而为端到端路径的每个卫星网络域选择合适的QoS类。最后,与现有端到端QoS类映射方案进行比较,仿真结果表明,上述方法在多卫星网络域环境下保证端到端的时延、时延抖动、丢包率和代价。 展开更多
关键词 卫星网络 软件定义网络 服务质量 服务质量映射
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基于遗传-蚁群优化算法的QoS组播路由算法设计 被引量:1
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作者 史郑延慧 何刚 《科学技术与工程》 北大核心 2024年第11期4626-4632,共7页
为了提高网络路由性能,提出并设计了一种基于遗传-蚁群优化算法的服务质量(quality of service,QoS)组播路由算法。首先,设计了自适应变频采集策略用于采集网络与节点信息,以此获得网络和节点的状态,为后续路由优化提供数据支持;其次,... 为了提高网络路由性能,提出并设计了一种基于遗传-蚁群优化算法的服务质量(quality of service,QoS)组播路由算法。首先,设计了自适应变频采集策略用于采集网络与节点信息,以此获得网络和节点的状态,为后续路由优化提供数据支持;其次,计算路径代价,将路径代价最小作为优化目标,建立QoS组播路由优化模型,并设置相关约束条件;最后,结合遗传算法和蚁群算法提出一种遗传-蚁群优化算法求解上述模型,输出最优路径,完成路由优化。实验结果表明,所提算法可有效降低路径长度与路径代价,提高搜索效率与路由请求成功率,优化后的路由时延抖动较小。 展开更多
关键词 遗传算法 数据采集 qos组播路由优化 蚁群算法 路径代价
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基于QoS约束的通信组网链路故障恢复探究
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作者 郭艳 《计算机产品与流通》 2024年第5期87-89,共3页
随着网络技术的不断发展,通信网的规模逐渐扩大,网络结构日渐趋于复杂化,发生故障的概率自然就会增高。当通信网出现故障后,必须尽快恢复,否则可能会造成巨大的经济损失,严重时甚至引发各类社会安全风险。智能通信网是解决上述问题的有... 随着网络技术的不断发展,通信网的规模逐渐扩大,网络结构日渐趋于复杂化,发生故障的概率自然就会增高。当通信网出现故障后,必须尽快恢复,否则可能会造成巨大的经济损失,严重时甚至引发各类社会安全风险。智能通信网是解决上述问题的有效策略之一,对网络带宽、时延、丢包率提出了不同的要求。本文对如何恢复网络故障展开了研究,提出了一种基于QoS(Quality of Service)约束的通信组网链路故障恢复方法,根据用户对业务提出的QoS需求以及空闲网络资源,选择恢复路径,确保传输业务的可靠性。在当通信网发生故障后,该方法能够有针对性地快速解决故障,对通信技术的应用与发展具有实用价值。 展开更多
关键词 链路故障恢复 通信网 传输业务 通信组网 网络故障 网络资源 有效策略 qos约束
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Quality of Service (QoS) Provisions in Wireless Sensor Networks and Related Challenges 被引量:1
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作者 Bhaskar Bhuyan Hiren Kumar Deva Sarma +2 位作者 Nityananda Sarma Avijit Kar Rajib Mall 《Wireless Sensor Network》 2010年第11期861-868,共8页
Wireless sensor networks (WSNs) are required to provide different levels of Quality of Services (QoS) based on the type of applications. Providing QoS support in wireless sensor networks is an emerging area of researc... Wireless sensor networks (WSNs) are required to provide different levels of Quality of Services (QoS) based on the type of applications. Providing QoS support in wireless sensor networks is an emerging area of research. Due to resource constraints like processing power, memory, bandwidth and power sources in sensor networks, QoS support in WSNs is a challenging task. In this paper, we discuss the QoS requirements in WSNs and present a survey of some of the QoS aware routing techniques in WSNs. We also explore the middleware approaches for QoS support in WSNs and finally, highlight some open issues and future direction of research for providing QoS in WSNs. 展开更多
关键词 WIRELESS Sensor Network quality of Service MIDDLEWARE ROUTING
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云服务推荐中基于多源特征和多任务学习的时序QoS预测 被引量:2
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作者 陈熳熳 王俊峰 +1 位作者 李晓慧 余坚 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期134-144,共11页
随着云计算技术的普及,云服务数量指数级增长,用户不再满足于功能性需求,服务质量(Quality of Service,QoS)成为比较服务优劣的关键性能指标.如何在动态、复杂的云环境中实时、准确地预测服务质量并为用户推荐高质量服务成为热点问题.... 随着云计算技术的普及,云服务数量指数级增长,用户不再满足于功能性需求,服务质量(Quality of Service,QoS)成为比较服务优劣的关键性能指标.如何在动态、复杂的云环境中实时、准确地预测服务质量并为用户推荐高质量服务成为热点问题.考虑到云服务器的负载、网络状态、用户接入云环境的偏好等随着时间变化,本文提出了基于多源特征和多任务学习的时序QoS预测方法(T-MST),它可以实时、准确地同时预测多种QoS属性.首先,TMST对用户、服务进行特征表示,通过Time2Vec刻画时序特征,再结合多种QoS属性的历史记录生成多源特征表示.其次,基于滑动窗口采用LSTM感知窗口内的时序关系,借助注意力机制细化窗口内不同时刻的关键性,从而构造待预测时刻的隐藏状态.最后,T-MST采用多任务预测层实现多种QoS属性的同时预测,它们共享上游模型,仅在预测层采用不同的感知模块以提升模型的鲁棒性和计算效率.本文基于真实世界的数据集进行了全面的实验验证,结果表明T-MST在吞吐量和响应时间的时序预测任务上平均绝对误差(Mean Absolute Error,MAE)分别平均提升了37.53%和20.38%,优于现有的时序QoS预测方法;而且TMST的计算效率更高,能够有效应对实时QoS预测的需求. 展开更多
关键词 云服务 qos预测 多源特征 多任务学习 深度学习
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基于QoS信息融合技术的无线传感网络容量改进算法研究
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作者 周莹 赵依苇 +1 位作者 尉理哲 刘半藤 《传感技术学报》 CSCD 北大核心 2024年第12期2137-2141,共5页
在确保网络容量不受影响的基础上,如何为通信业务提供高质量的服务保障(QoS),已经成为无线传感网络研究的焦点话题。基于Gupta和Kumar等学者提出的经典网络容量模型,整合网络层的QoS参数信息,进而设计一种融合物理层与网络层特性的跨层... 在确保网络容量不受影响的基础上,如何为通信业务提供高质量的服务保障(QoS),已经成为无线传感网络研究的焦点话题。基于Gupta和Kumar等学者提出的经典网络容量模型,整合网络层的QoS参数信息,进而设计一种融合物理层与网络层特性的跨层网络容量计算策略。首先,构建Grover节点状态的数学模型,详细描述网络延迟和节点能量消耗等QoS参数;然后,我们采用D-S证据理论对QoS信息进行整合,从而计算出网络链路的概率。最终,把QoS信息融合修正传统公式,并为跨层网络的容量制定算法。最后,文章构建仿真环境,对经典网络容量算法与跨层网络容量算法进行对比分析。研究结果显示,跨层网络容量算法在稳定性和可靠性方面表现得更为出色。 展开更多
关键词 网络容量 GROVER算法 服务质量保障 证据理论
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