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Theory and practice for assessing structural integrity and dynamical integrity of high-speed trains
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作者 Weihua Zhang Yuanchen Zeng +1 位作者 Dongli Song Zhiwei Wang 《Railway Sciences》 2024年第2期113-127,共15页
Purpose–The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system.This paper aims to define and substantiate the ass... Purpose–The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system.This paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and practice.The key principles and approacheswill be proposed,and their applications to high-speed trains in Chinawill be presented.Design/methodology/approach–First,the structural integrity and dynamical integrity of high-speed trains are defined,and their relationship is introduced.Then,the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are provided.Finally,the principles and approaches for assessing the dynamical integrity of highspeed trains are presented and a novel operational assessment method is further presented.Findings–Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle system.For assessing the structural integrity of structural components,an open-loop analysis considering both normal and abnormal vehicle conditions is needed.For assessing the structural integrity of dynamical components,a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is needed.The analysis of vehicle system dynamics should follow the principles of complete objects,conditions and indices.Numerical,experimental and operational approaches should be combined to achieve effective assessments.Originality/value–The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects,better lifespan management of train components and better maintenance decision-making for high-speed trains. 展开更多
关键词 Structural integrity Dynamical integrity Vehicle system dynamics High-speed trains BOGIE integrity assessment FATIGUE
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Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction
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作者 Estel Viñolas-Vergés Jordi Ribas-Maynou +4 位作者 Isabel Barranco Camila Peres Rubio Sergi Bonet Jordi Roca Marc Yeste 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期171-181,共11页
Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separa... Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separate fractions:pre-sperm,sperm-rich(SRF)and post sperm-rich(PSRF).These fractions are known to vary in volume,sperm concentration and quality,as well as in the origin and composition of seminal plasma(SP),with differences being also observed within the SRF one.Yet,whether disparities in the DNA integrity and chromatin condensation and pro-tamination of their sperm exist has not been interrogated.Results This study determined chromatin protamination(Chromomycin A3 test,CMA_(3)),condensation(Dibromobi-mane test,DBB),and DNA integrity(Comet assay)in the pig sperm contained in the first 10 m L of the SRF(SRF-P1),the remaining portion of the sperm-rich fraction(SRF-P2),and the post sperm-rich fraction(PSRF).While chromatin protamination was found to be similar between the different ejaculate fractions(P>0.05),chromatin condensation was seen to be greater in SRF-P1 and SRF-P2 than in the PSRF(P=0.018 and P=0.004,respectively).Regarding DNA integrity,no differences between fractions were observed(P>0.05).As the SRF-P1 has the highest sperm concentra-tion and ejaculate fractions are known to differ in antioxidant composition,the oxidative stress index(OSi)in SP,calcu-lated as total oxidant activity divided by total antioxidant capacity,was tested and confirmed to be higher in the SRF-P1 than in SRF-P2 and PSRF(0.42±0.06 vs.0.23±0.09 and 0.08±0.00,respectively;P<0.01);this index,in addition,was observed to be correlated to the sperm concentration of each fraction(Rs=0.973;P<0.001).Conclusion While sperm DNA integrity was not found to differ between ejaculate fractions,SRF-P1 and SRF-P2 were observed to exhibit greater chromatin condensation than the PSRF.This could be related to the OSi of each fraction. 展开更多
关键词 CHROMATIN Condensation DNA integrity Ejaculate fractions PIG Protamination SPERM
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Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity
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作者 Nianwei Xu Renke Kang +4 位作者 Bi Zhang Yuan Zhang Chenxu Wang Yan Bao Zhigang Dong 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期458-475,共18页
Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),... Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining processes.Normal-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue strength.The lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue properties.In this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was developed.Then,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was analyzed.Based on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were furtherpredicted.The predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI indexes.Finally,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted results.According to the critical condition,an SI field where FCI sites appeared in the bulk material could be obtained.In this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%. 展开更多
关键词 surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding
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Preserving Data Secrecy and Integrity for Cloud Storage Using Smart Contracts and Cryptographic Primitives
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作者 Maher Alharby 《Computers, Materials & Continua》 SCIE EI 2024年第5期2449-2463,共15页
Cloud computing has emerged as a viable alternative to traditional computing infrastructures,offering various benefits.However,the adoption of cloud storage poses significant risks to data secrecy and integrity.This a... Cloud computing has emerged as a viable alternative to traditional computing infrastructures,offering various benefits.However,the adoption of cloud storage poses significant risks to data secrecy and integrity.This article presents an effective mechanism to preserve the secrecy and integrity of data stored on the public cloud by leveraging blockchain technology,smart contracts,and cryptographic primitives.The proposed approach utilizes a Solidity-based smart contract as an auditor for maintaining and verifying the integrity of outsourced data.To preserve data secrecy,symmetric encryption systems are employed to encrypt user data before outsourcing it.An extensive performance analysis is conducted to illustrate the efficiency of the proposed mechanism.Additionally,a rigorous assessment is conducted to ensure that the developed smart contract is free from vulnerabilities and to measure its associated running costs.The security analysis of the proposed system confirms that our approach can securely maintain the confidentiality and integrity of cloud storage,even in the presence of malicious entities.The proposed mechanism contributes to enhancing data security in cloud computing environments and can be used as a foundation for developing more secure cloud storage systems. 展开更多
关键词 Cloud storage data secrecy data integrity smart contracts CRYPTOGRAPHY
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Aging impairs the osteocytic regulation of collagen integrity and bone quality
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作者 Charles A.Schurman Serra Kaya +12 位作者 Neha Dole Nadja M.Maldonado Luna Natalia Castillo Ryan Potter Jacob P.Rose Joanna Bons Christina D.King Jordan B.Burton Birgit Schilling Simon Melov Simon Tang Eric Schaible Tamara Alliston 《Bone Research》 SCIE CAS CSCD 2024年第1期78-94,共17页
Poor bone quality is a major factor in skeletal fragility in elderly individuals.The molecular mechanisms that establish and maintain bone quality,independent of bone mass,are unknown but are thought to be primarily d... Poor bone quality is a major factor in skeletal fragility in elderly individuals.The molecular mechanisms that establish and maintain bone quality,independent of bone mass,are unknown but are thought to be primarily determined by osteocytes.We hypothesize that the age-related decline in bone quality results from the suppression of osteocyte perilacunar/canalicular remodeling(PLR),which maintains bone material properties.We examined bones from young and aged mice with osteocyte-intrinsic repression of TGFβsignaling(TβRII^(ocy−/−))that suppresses PLR.The control aged bone displayed decreased TGFβsignaling and PLR,but aging did not worsen the existing PLR suppression in male TβRII^(ocy−/−)bone.This relationship impacted the behavior of collagen material at the nanoscale and tissue scale in macromechanical tests.The effects of age on bone mass,density,and mineral material behavior were independent of osteocytic TGFβ.We determined that the decline in bone quality with age arises from the loss of osteocyte function and the loss of TGFβ-dependent maintenance of collagen integrity. 展开更多
关键词 MAINTAIN primarily integrity
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Perspectives from a publishing ethics and research integrity team for required improvements 被引量:1
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作者 Sabina Alam Laura Wilson 《Journal of Data and Information Science》 CSCD 2023年第3期1-14,共14页
It is imperative that all stakeholders within the research ecosystem take responsibility to improve research integrity and reliability of published research.Based on the unique experiences of a specialist publishing e... It is imperative that all stakeholders within the research ecosystem take responsibility to improve research integrity and reliability of published research.Based on the unique experiences of a specialist publishing ethics and research integrity team within a major publisher,this article provides insights into the observed trends of misconduct and how those have evolved over time,and addresses key actions needed to improve the interface between researchers,funders,institutions and publishers to collectively improve research integrity on a global scale. 展开更多
关键词 Research integrity Publishing ethics Training Education
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Passive Attack Detection for a Class of Stealthy Intermittent Integrity Attacks 被引量:1
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作者 Kangkang Zhang Christodoulos Keliris +2 位作者 Thomas Parisini Bin Jiang Marios M.Polycarpou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第4期898-915,共18页
This paper proposes a passive methodology for detecting a class of stealthy intermittent integrity attacks in cyberphysical systems subject to process disturbances and measurement noise.A stealthy intermittent integri... This paper proposes a passive methodology for detecting a class of stealthy intermittent integrity attacks in cyberphysical systems subject to process disturbances and measurement noise.A stealthy intermittent integrity attack strategy is first proposed by modifying a zero-dynamics attack model.The stealthiness of the generated attacks is rigorously investigated under the condition that the adversary does not know precisely the system state values.In order to help detect such attacks,a backward-in-time detection residual is proposed based on an equivalent quantity of the system state change,due to the attack,at a time prior to the attack occurrence time.A key characteristic of this residual is that its magnitude increases every time a new attack occurs.To estimate this unknown residual,an optimal fixed-point smoother is proposed by minimizing a piece-wise linear quadratic cost function with a set of specifically designed weighting matrices.The smoother design guarantees robustness with respect to process disturbances and measurement noise,and is also able to maintain sensitivity as time progresses to intermittent integrity attack by resetting the covariance matrix based on the weighting matrices.The adaptive threshold is designed based on the estimated backward-in-time residual,and the attack detectability analysis is rigorously investigated to characterize quantitatively the class of attacks that can be detected by the proposed methodology.Finally,a simulation example is used to demonstrate the effectiveness of the developed methodology. 展开更多
关键词 Backward-in-time equivalent quantity fixed-point smoother intermittent integrity attacks
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An unequal fracturing stage spacing optimization model for hydraulic fracturing that considers cementing interface integrity 被引量:1
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作者 Xu Han Fu-Ping Feng +5 位作者 Xiao-Chuan Zhang Jing Cao Jun Zhang Yu Suo Yan Yan Mao-Sen Yan 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2165-2186,共22页
Determining reasonable fracturing stage spacing is the key to horizontal well fracturing.Different from traditional stage spacing optimization methods based on the principle of maximum stimulated reservoir volume,in t... Determining reasonable fracturing stage spacing is the key to horizontal well fracturing.Different from traditional stage spacing optimization methods based on the principle of maximum stimulated reservoir volume,in this paper,by considering the integrity of the wellbore interface,a fracture propagation model was established based on displacement discontinuity method and the competition mechanism of multifracture joint expansion,leading to the proposal of an unequal stage spacing optimization model.The results show that in the first stage,the interfacial fractures spread symmetrically along the axis of the central point during that stage,while in the second and subsequent stages,the interfacial fractures of each cluster extend asymmetrically along the left and right sides.There are two kinds of interface connectivity behaviour:in one,the existing fractures first extend and connect within the stage,and in the other,the fractures first extend in the direction close to the previous stage,with the specific behaviour depending on the combined effect of stress shadow and flow competition during hydraulic fracture expansion.The stage spacing is positively correlated with the number of fractures and Young’s modulus of the cement and formation and is negatively correlated with the cluster spacing and horizontal principal stress difference.The sensitivity is the strongest when the Young’s modulus of the cement sheath is 10-20 GPa,and the sensitivity of the horizontal principal stress difference is the weakest. 展开更多
关键词 Hydraulic fracturing Cementing interface Fracture propagation Fracturing stage spacing Wellbore integrity
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Phytogenic feed additives alleviate pathogenic Escherichia coli-induced intestinal damage through improving barrier integrity and inhibiting inflammation in weaned pigs 被引量:1
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作者 Se Yeon Chang Min Ho Song +11 位作者 Ji Hwan Lee Han Jin Oh Yong Ju Kim Jae Woo An Young Bin Go Dong Cheol Song Hyun AhCho Seung Yeol Cho Dong Jun Kim Mi Suk Kim Hyeun Bum Kim Jin Ho Cho 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期295-306,共12页
Background:This study was conducted to investigate the effects of each phytogenic feed additive(PFA;PFA1,bitter citrus extract;PFA2,a microencapsulated blend of thymol and carvacrol;PFA3,a mixture of bitter citrus ext... Background:This study was conducted to investigate the effects of each phytogenic feed additive(PFA;PFA1,bitter citrus extract;PFA2,a microencapsulated blend of thymol and carvacrol;PFA3,a mixture of bitter citrus extract,thymol,and carvacrol;PFA4,a premixture of grape seed,grape marc extract,green tea,and hops;PFA5,fenugreek seed powder)on the growth performance,nutrient digestibility,intestinal morphology,and immune response in weaned pigs infected with Escherichia coli(E.coli).Results:A total of 634-week-old weaned pigs were placed in individual metabolic cages and assigned to seven treatment groups.The seven treatments were as follows:1)NC;basal diet without E.coli challenge,2)PC;basal diet with E.coli challenge,3)T1;PC+0.04%PFA1,4)T2;PC+0.01%PFA2,5)T3;PC+0.10%PFA3,6)T4;PC+0.04%PFA4,7)T5;PC+0.10%PFA5.The experiments lasted in 21 d,including 7 d before and 14 d after the first E.coli challenge.In the E.coli challenge treatments,all pigs were orally inoculated by dividing a total of 10 mL of E.coli F18 for 3 consecutive days.The PFA-added groups significantly increased(P<0.05)average daily gain and feed efficiency and decreased(P<0.05)the fecal score at d 0 to 14 post-inoculation(PI).Tumor necrosis factorαwas significantly lower(P<0.05)in the PFA-added groups except for T1 in d 14 PI compared to the PC treatment.The T3 had a higher(P<0.05)immunoglobulin G and immunoglobulin A concentration compared to the PC treatment at d 7 PI.Also,T3 showed significantly higher(P<0.05)villus height:crypt depth and claudin 1 expression in ileal mucosa,and significantly downregulated(P<0.05)the expression of calprotectin compared to the PC treatment.Conclusions:Supplementation of PFA in weaned pigs challenged with E.coli alleviated the negative effects of E.coli and improved growth performance.Among them,the mixed additive of bitter citrus extract,thymol,and carvacrol showed the most effective results,improving immune response,intestinal morphology,and expression of tight junctions. 展开更多
关键词 Barrier integrity Escherichia coli Immunity Phytogenic feed additive Post-weaning diarrhea Weaned pigs
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Failure mechanism and influencing factors of cement sheath integrity under alternating pressure 被引量:1
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作者 Kuan-Hai Deng Nian-Tao Zhou +4 位作者 Yuan-Hua Lin Yan-Xian Wu Jie Chen Chang Shu Peng-Fei Xie 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2413-2427,共15页
The failure of cement sheath integrity can be easily caused by alternating pressure during large-scale multistage hydraulic fracturing in shale-gas well.An elastic-plastic mechanical model of casing-cement sheath-form... The failure of cement sheath integrity can be easily caused by alternating pressure during large-scale multistage hydraulic fracturing in shale-gas well.An elastic-plastic mechanical model of casing-cement sheath-formation(CSF)system under alternating pressure is established based on the Mohr-Coulomb criterion and thick-walled cylinder theory,and it has been solved by MATLAB programming combining global optimization algorithm with Global Search.The failure mechanism of cement sheath integrity is investigated,by which it can be seen that the formation of interface debonding is mainly related to the plastic strain accumulation,and there is a risk of interface debonding under alternating pressure,once the cement sheath enters plasticity whether in shallow or deep well sections.The matching relationship between the mechanical parameters(elastic modulus and Poisson's ratio)of cement sheath and its integrity failure under alternating pressure in whole well sections is studied,by which it has been found there is a“critical range”in the Poisson's ratio of cement sheath.When the Poisson's ratio is below the“critical range”,there is a positive correlation between the yield internal pressure of cement sheath(SYP)and its elastic modulus.However,when the Poisson's ratio is above the“critical range”,there is a negative correlation.The elastic modulus of cement sheath is closely related to its Poisson's ratio,and restricts each other.Scientific and reasonable matching between mechanical parameters of cement sheath and CSF system under different working conditions can not only reduce the cost,but also protect the cement sheath integrity. 展开更多
关键词 Casing-cement sheath-formation system Mechanical model Matching relationship Cement sheath integrity Critical range Mechanical parameters
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Insights into the relations between cell wall integrity and in vitro digestion properties of granular starches in pulse cotyledon cells after dry heat treatment 被引量:1
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作者 Ping Li Bin Zhang +5 位作者 Rui Liu Li Ding Xiong Fu Haiteng Li Qiang Huang Xiaowei He 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期528-535,共8页
Natural foods,such as whole pulses,are recommended in the dietary guidelines of the US and China.The plant cell wall structure in whole pulses has important implications for the nutritional functionalities of starch.I... Natural foods,such as whole pulses,are recommended in the dietary guidelines of the US and China.The plant cell wall structure in whole pulses has important implications for the nutritional functionalities of starch.In this study,garbanzo bean cells with varying degrees of cell wall integrity were subjected to dry heat treatment(DHT)and used to elucidate the food structure-starch digestion properties of pulse food.The morphological features suggested that all cell samples do not exhibit remarkable changes after being subjected to DHT.Molecular rearrangement and the crystallite disruption of starch granules entrapped in cells occurred during DHT as assessed by the crystal structure and thermal properties.DHT decreased the inhibitory effects of enzymes of both the soluble and insoluble components,but the digestion rate and extent of slightly and highly damaged cell samples did not exhibit significant differences compared with their native counterparts.We concluded that the starch digestion of pulse cotyledon cells is primarily determined by the intactness of the cellular structure.This study reveals the role of food structure on the ability to retain the desirable nutritional properties of starch after subjection to physical modification. 展开更多
关键词 Cell wall integrity In vitro starch digestion PULSE Dry heat treatment
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Determination of rock mass integrity coefficient using a non-invasive geophysical approach 被引量:1
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作者 Muhammad Hasan Yanjun Shang +2 位作者 Xuetao Yi Peng Shao Meng He 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1426-1440,共15页
Determination of rock mechanical parameters is the most important step in rock mass quality evaluation and has significant impacts on geotechnical engineering practice.Rock mass integrity coefficient(KV)is one of the ... Determination of rock mechanical parameters is the most important step in rock mass quality evaluation and has significant impacts on geotechnical engineering practice.Rock mass integrity coefficient(KV)is one of the most efficient parameters,which is conventionally determined from boreholes.Such approaches,however,are time-consuming and expensive,offer low data coverage of point measurements,require heavy equipment,and are hardly conducted in steep topographic sites.Hence,borehole approaches cannot assess the subsurface thoroughly for rock mass quality evaluation.Alternatively,use of geophysical methods is non-invasive,rapid and economical.The proposed geophysical approach makes useful empirical correlation between geophysical and geotechnical parameters.We evaluated the rock mass quality via integration between KV measured from the limited boreholes and inverted resistivity obtained from electrical resistivity tomography(ERT).The borehole-ERT correlation provided KV along various geophysical profiles for more detailed 2D/3D(two-/three-dimensional)mapping of rock mass quality.The subsurface was thoroughly evaluated for rock masses with different engineering qualities,including highly weathered rock,semi-weathered rock,and fresh rock.Furthermore,ERT was integrated with induced polarization(IP)to resolve the uncertainty caused by water/clay content.Our results show that the proposed method,compared with the conventional approaches,can reduce the ambiguities caused by inadequate data,and give more accurate insights into the subsurface for rock mass quality evaluation. 展开更多
关键词 Geotechnical engineering Rock mass integrity coefficient Rock mechanical parameters Geophysical parameters Electrical resistivity tomography(ERT) Induced polarization(IP)
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Surface Integrity of Inconel 738LC Parts Manufactured by Selective Laser Melting Followed by High-speed Milling
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作者 Guanhui Ren Sai Guo Bi Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第1期65-79,共15页
This study is concerned with the surface integrity of Inconel 738LC parts manufactured by selective laser melting(SLM)followed by high-speed milling(HSM).In the investigation process of surface integrity,the study emp... This study is concerned with the surface integrity of Inconel 738LC parts manufactured by selective laser melting(SLM)followed by high-speed milling(HSM).In the investigation process of surface integrity,the study employs ultradepth three-dimensional microscopy,laser scanning confocal microscopy,scanning electron microscopy,electron backscatter diffractometry,and energy dispersive spectroscopy to characterize the evolution of material microstructure,work hardening,residual stress coupling,and anisotropic effect of the building direction on surface integrity of the samples.The results show that SLM/HSM hybrid manufacturing can be an effective method to obtain better surface quality with a thinner machining metamorphic layer.High-speed machining is adopted to reduce cutting force and suppress machining heat,which is an effective way to produce better surface mechanical properties during the SLM/HSM hybrid manufacturing process.In general,high-speed milling of the SLM-built Inconel 738LC samples offers better surface integrity,compared to simplex additive manufacturing or casting. 展开更多
关键词 Surface integrity Inconel 738LC Selective laser melting High-speed milling
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Blockchain and Data Integrity Authentication Technique for Secure Cloud Environment
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作者 A.Ramachandran P.Ramadevi +1 位作者 Ahmed Alkhayyat Yousif Kerrar Yousif 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期2055-2070,共16页
Nowadays,numerous applications are associated with cloud and user data gets collected globally and stored in cloud units.In addition to shared data storage,cloud computing technique offers multiple advantages for the ... Nowadays,numerous applications are associated with cloud and user data gets collected globally and stored in cloud units.In addition to shared data storage,cloud computing technique offers multiple advantages for the user through different distribution designs like hybrid cloud,public cloud,community cloud and private cloud.Though cloud-based computing solutions are highly con-venient to the users,it also brings a challenge i.e.,security of the data shared.Hence,in current research paper,blockchain with data integrity authentication technique is developed for an efficient and secure operation with user authentica-tion process.Blockchain technology is utilized in this study to enable efficient and secure operation which not only empowers cloud security but also avoids threats and attacks.Additionally,the data integrity authentication technique is also uti-lized to limit the unwanted access of data in cloud storage unit.The major objec-tive of the projected technique is to empower data security and user authentication in cloud computing environment.To improve the proposed authentication pro-cess,cuckoofilter and Merkle Hash Tree(MHT)are utilized.The proposed meth-odology was validated using few performance metrics such as processing time,uploading time,downloading time,authentication time,consensus time,waiting time,initialization time,in addition to storage overhead.The proposed method was compared with conventional cloud security techniques and the outcomes establish the supremacy of the proposed method. 展开更多
关键词 Blockchain SECURITY data integrity AUTHENTICATION cloud computing SIGNATURE hash tree
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Data Integrity and Risk
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作者 Sasidhar Duggineni 《Open Journal of Optimization》 2023年第2期25-33,共9页
Data Integrity is a critical component of Data lifecycle management. Its importance increases even more in a complex and dynamic landscape. Actions like unauthorized access, unauthorized modifications, data manipulati... Data Integrity is a critical component of Data lifecycle management. Its importance increases even more in a complex and dynamic landscape. Actions like unauthorized access, unauthorized modifications, data manipulations, audit tampering, data backdating, data falsification, phishing and spoofing are no longer restricted to rogue individuals but in fact also prevalent in systematic organizations and states as well. Therefore, data security requires strong data integrity measures and associated technical controls in place. Without proper customized framework in place, organizations are prone to high risk of financial, reputational, revenue losses, bankruptcies, and legal penalties which we shall discuss further throughout this paper. We will also explore some of the improvised and innovative techniques in product development to better tackle the challenges and requirements of data security and integrity. 展开更多
关键词 Data Governance Data integrity Data Management Data Security Technical Controls REGULATIONS
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THM coupled analysis of cement sheath integrity considering well
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作者 Xiao-Rong Li Chen-Wang Gu +1 位作者 Ze-Chen Ding Yong-Cun Feng 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期447-459,共13页
he cement sheath is the heart of any oil or gas well for providing zonal isolation and well integrity during the life of a well.Loads induced by well construction operations and borehole pressure and temperature chang... he cement sheath is the heart of any oil or gas well for providing zonal isolation and well integrity during the life of a well.Loads induced by well construction operations and borehole pressure and temperature changes may lead to the ultimate failure of cement sheath.This paper quantifies the potential of cement failure under mechanically and thermally induced stress during the life-of-well using a coupled thermalehydrologicalemechanical(THM)modeling approach.A staged finite-element procedure is presented considering sequential stress and displacement development during each stage of the well life,including drilling,casing,cementing,completion,production,and injection.The staged model quantifies the stress states and state variables,e.g.,plastic strain,damage,and debonding at cement/rock or cement/casing interface,in each well stage from simultaneous action of in-situ stress,pore pressure,temperature,casing pressure,and cement hardening/shrinkage.Thus,it eliminates the need to guess the initial stress and strain state before modeling a specific stage.Moreover,coupled THM capabilities of the model ensure the full consideration of the interaction between these influential factors. 展开更多
关键词 Cement sheath integrity Thermal-hydrological-mechanical Whole life cycle Cement sheath shrinkage Initial stresses
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Utilizing Machine Learning with Unique Pentaplet Data Structure to Enhance Data Integrity
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作者 Abdulwahab Alazeb 《Computers, Materials & Continua》 SCIE EI 2023年第12期2995-3014,共20页
Data protection in databases is critical for any organization,as unauthorized access or manipulation can have severe negative consequences.Intrusion detection systems are essential for keeping databases secure.Advance... Data protection in databases is critical for any organization,as unauthorized access or manipulation can have severe negative consequences.Intrusion detection systems are essential for keeping databases secure.Advancements in technology will lead to significant changes in the medical field,improving healthcare services through real-time information sharing.However,reliability and consistency still need to be solved.Safeguards against cyber-attacks are necessary due to the risk of unauthorized access to sensitive information and potential data corruption.Dis-ruptions to data items can propagate throughout the database,making it crucial to reverse fraudulent transactions without delay,especially in the healthcare industry,where real-time data access is vital.This research presents a role-based access control architecture for an anomaly detection technique.Additionally,the Structured Query Language(SQL)queries are stored in a new data structure called Pentaplet.These pentaplets allow us to maintain the correlation between SQL statements within the same transaction by employing the transaction-log entry information,thereby increasing detection accuracy,particularly for individuals within the company exhibiting unusual behavior.To identify anomalous queries,this system employs a supervised machine learning technique called Support Vector Machine(SVM).According to experimental findings,the proposed model performed well in terms of detection accuracy,achieving 99.92%through SVM with One Hot Encoding and Principal Component Analysis(PCA). 展开更多
关键词 Database intrusion detection system data integrity machine learning pentaplet data structure
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ZmDRR206 functions in maintaining cell wall integrity during maize seedling growth and defense response to external stresses
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作者 Tao Zhong Suining Deng +3 位作者 Mang Zhu Xingming Fan Mingliang Xu Jianrong Ye 《The Crop Journal》 SCIE CSCD 2023年第6期1649-1664,共16页
Plants adaptively change their cell wall composition and structure during their growth,development,and interactions with environmental stresses.Dirigent proteins(DIRs)contribute to environmental adaptations by dynamic... Plants adaptively change their cell wall composition and structure during their growth,development,and interactions with environmental stresses.Dirigent proteins(DIRs)contribute to environmental adaptations by dynamically reorganizing the cell wall and/or by generating defense compounds.A maize DIR,ZmDRR206,was previously reported to play a dominant role in regulation of storage nutrient accumulation in endosperm during maize kernel development.Here we show that ZmDRR206 mediates maize seedling growth and disease resistance by coordinately regulating biosynthesis of cell wall components for cell-wall integrity(CWI)maintenance.Expression of ZmDRR206 was induced in maize seedlings upon pathogen infection.ZmDRR206 overexpression in maize resulted in reduced seedling growth and photosynthetic activity but increased disease resistance and drought tolerance,revealing a tradeoff between growth and defense.Consistently,ZmDRR206 overexpression reduced the contents of primary metabolites and down-regulated genes involved in photosynthesis,while increasing the contents of major cell wall components,defense phytohormones,and defense metabolites,and up-regulated genes involved in defense and cell-wall biosynthesis in seedlings.ZmDRR206-overexpressing seedlings were resistant to cell-wall stress imposed by isoxaben,and ZmDRR206 physically interacted with ZmCesA10,which is a cellulose synthase unit.Our findings suggest a mechanism by which ZmDRR206 coordinately regulates biosynthesis of cell-wall components for CWI maintenance during maize seedling growth,and might be exploited for breeding strong disease resistance in maize. 展开更多
关键词 Cell-wall integrity Cell-wall biosynthesis Dirigent protein ZmDRR206 Defense response Seedling growth
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Optimize Multiple Peening Effects on Surface Integrity and Microhardness of Aluminum Alloy Induced by LSP
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作者 Enoch Asuako Larson Samuel Adu-Gyamfi +7 位作者 Milku Augustine Philip Yamba Jamal-Deen Kukurah Karimu Abdulai Joseph Sekyi-Ansah Osman Abdul-Razak Emmanuel A. Akurugu Aston Kuzmin 《Materials Sciences and Applications》 2023年第3期208-221,共14页
Laser shock peening is a modernized surface enhancement performed methodically to improve fatigue life, enhance the hardness of the material and make coarse grains flat under the superficial layer. In this current stu... Laser shock peening is a modernized surface enhancement performed methodically to improve fatigue life, enhance the hardness of the material and make coarse grains flat under the superficial layer. In this current study, the effect of varying optimized multiple laser shock peening (LSP) is studied on the surface integrity, microhardness, and mechanical properties. The results show that the LSP-treated specimens have visible signs of valleys, wavy and varying height distribution as well as dimples. However, the presence of non-uniformity and sharp protrusions was detected from the superficiality of the as-received specimen and this was so because of the SiC abrasive material used to polish the superficial layer of the specimen before the test experiment. Prior to LSP, the surface roughness was 2 μm, however, after LSP the roughness increased to 4 μm, 6 μm and 17 μm for 1, 2, and 4 impacts, respectively. High-density dislocation can also be observed close to the grain boundary because the grain boundary prevents the migration of dislocation which could lead to dislocation walls and dislocation tangles. The increase in impacts decrease the average grain size, nevertheless, the micro-strain increased after multiple impacts. Furthermore, coarse grains after LSP were transformed into finer grains. The increase in the number of impacts increases the micro-strain likewise the full-width half maximum (FWHM). Finally, the increase in microhardness increases as the LSP impacts increase. 展开更多
关键词 Surface integrity MICROHARDNESS Sharp Protrusions SiC Abrasive Material FWHM
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Thermal integrity profiling of cast-in-situ piles in sand using fiber-optic distributed temperature sensing
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作者 Jing Wang Honghu Zhu +4 位作者 Daoyuan Tan Zili Li Jie Li Chao Wei Bin Shi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3244-3255,共12页
Defects in cast-in-situ piles have an adverse impact on load transfer at the pile‒soil interface and pile bearing capacity. In recent years, thermal integrity profiling (TIP) has been developed to measure temperature ... Defects in cast-in-situ piles have an adverse impact on load transfer at the pile‒soil interface and pile bearing capacity. In recent years, thermal integrity profiling (TIP) has been developed to measure temperature profiles of cast-in-situ piles, enabling the detection of structural defects or anomalies at the early stage of construction. However, using this integrity testing method to evaluate potential defects in cast-in-situ piles requires a comprehensive understanding of the mechanism of hydration heat transfer from piles to surrounding soils. In this study, small-scale model tests were conducted in laboratory to investigate the performance of TIP in detecting pile integrity. Fiber-optic distributed temperature sensing (DTS) technology was used to monitor detailed temperature variations along model piles in sand. Additionally, sensors were installed in sand to measure water content and matric suction. An interpretation method against available DTS-based thermal profiles was proposed to reveal the potential defective regions. It shows that the temperature difference between normal and defective piles is more obvious in wet sand. In addition, there is a critical zone of water migration in sand due to the water absorption behavior of cement and temperature transfer-induced water migration in the early-age concrete setting. These findings could provide important insight into the improvement of the TIP testing method for field applications. 展开更多
关键词 Geotechnical monitoring Distributed temperature sensing(DTS) Pile defect Fiber-optic thermal integrity profiling(FO-TIP) Heat transfer Pile‒soil interface
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