25 research outputs found

    Interior Eigensolver Based on Rational Filter with Composite rule

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    Contour integral based rational filter leads to interior eigensolvers for non-Hermitian generalized eigenvalue problems. Based on the Zolotarev's problems, this paper proves the asymptotic optimality of the trapezoidal quadrature of the contour integral in terms of the rational function separation. A composite rule of the trapezoidal quadrature is derived. Two interior eigensolvers are proposed based on the composite rule. Both eigensolvers adopt direct factorization and multi-shift generalized minimal residual method for the inner and outer rational functions, respectively. The first eigensolver fixes the order of the outer rational function and applies the subspace iteration to achieve convergence, whereas the second eigensolver doubles the order of the outer rational function every iteration to achieve convergence without subspace iteration. The efficiency and stability of proposed eigensolvers are demonstrated on synthetic and practical sparse matrix pencils.Comment: 28 pages,26 figure

    Three-Level Supply Chain Coordination under Disruptions Based on Revenue-Sharing Contract with Price Dependent Demand

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    Considering the market demand is stochastic and dependent on price, this paper shows that the revenue-sharing contract could coordinate a three-level supply chain consisting of one manufacturer, one distributor, and one retailer under normal environment. However, the original revenue-sharing contract cannot coordinate the supply chain under disruptions in circumstances of certain incidents leading to significant changes in market demand and causing additional deviation costs. To solve the problem, this essay introduces two improved forms of revenue-sharing contract: a mixed contract form based on a quantity discount policy and a pure form, which are characterized by antidisruption ability. The model of improved revenue-sharing contract is optimized when the market demand is in the additive form or in the multiplicative form with price dependent demand. Formulas are given to calculate the optimal contract parameters. Finally, this essay demonstrates the accuracy of the model of improved revenue-sharing contract with the help of numerical examples

    Three-Level Supply Chain Coordination under Disruptions Based on Revenue-Sharing Contract with Price Dependent Demand

    Get PDF
    Considering the market demand is stochastic and dependent on price, this paper shows that the revenue-sharing contract could coordinate a three-level supply chain consisting of one manufacturer, one distributor, and one retailer under normal environment. However, the original revenue-sharing contract cannot coordinate the supply chain under disruptions in circumstances of certain incidents leading to significant changes in market demand and causing additional deviation costs. To solve the problem, this essay introduces two improved forms of revenue-sharing contract: a mixed contract form based on a quantity discount policy and a pure form, which are characterized by antidisruption ability. The model of improved revenue-sharing contract is optimized when the market demand is in the additive form or in the multiplicative form with price dependent demand. Formulas are given to calculate the optimal contract parameters. Finally, this essay demonstrates the accuracy of the model of improved revenue-sharing contract with the help of numerical examples

    Coordinating Three-Level Supply Chain by Revenue-Sharing Contract with Sales Effort Dependent Demand

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    Revenue-sharing contract is a kind of mechanism to improve performance or to achieve perfect coordination of supply chain. Considering a three-level supply chain consisting of a manufacturer, a distributor, and a retailer who faces a stochastic and sales effort dependent demand, the paper analyzes the impact of sales effort on supply chain coordination and expounds the reasons why traditional revenue-sharing contract cannot coordinate supply chain in this condition. Given three cases: only the retailer bears the sales effort cost, only the manufacturer bears the sales effort cost, and the retailer bears the sales effort cost with the manufacturer, the paper proposes an improved revenue-sharing contract based on quantity discount policy to coordinate the supply chain. It illustrates that improved revenue sharing contract can coordinate supply chain by implementing it in one transaction or two transactions of three-level supply chain. The model of improved revenue-sharing contract is optimized, respectively, by addition form and multiplication form with sales effort dependent demand. Formulas are given to determine the optimal contract parameters. Finally, numerical experiments are given to test the accuracy of the model of improved revenue-sharing contract

    Cross-Correlation Forecast of CSST Spectroscopic Galaxy and MeerKAT Neutral Hydrogen Intensity Mapping Surveys

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    Cross-correlating the data of neutral hydrogen (HI) 21cm intensity mapping with galaxy surveys is an effective method to extract astrophysical and cosmological information. In this work, we investigate the cross-correlation of MeerKAT single-dish mode HI intensity mapping and China Space Station Telescope (CSST) spectroscopic galaxy surveys. We simulate a survey area of 300\sim 300 deg2\mathrm{deg}^2 of MeerKAT and CSST surveys at z=0.5z=0.5 using Multi-Dark N-body simulation. The PCA algorithm is applied to remove the foregrounds of HI intensity mapping, and signal compensation is considered to solve the signal loss problem in the HI-galaxy cross power spectrum caused by the foreground removal process. We find that from CSST galaxy auto and MeerKAT-CSST cross power spectra, the constraint accuracy of the parameter product ΩHIbHIrHI,g\Omega_{\rm HI}b_{\rm HI}r_{{\rm HI},g} can reach to 1%\sim1\%, which is about one order of magnitude higher than the current results. After performing the full MeerKAT HI intensity mapping survey with 5000 deg2^2 survey area, the accuracy can be enhanced to <0.3%<0.3\%. This implies that the MeerKAT-CSST cross-correlation can be a powerful tool to probe the cosmic HI property and the evolution of galaxies and the Universe.Comment: 17 pages, 11 figures, 3 tables. Accepted for publication in RA

    THE LEVEL OF READINES TRAINEE TEACHERS IN THE INSTITUTE OF TEACHER EDUCATION TECHNICAL EDUCATION CAMPUS FOR SPECIAL NEEDS STUDENTS IN TVET SUBJECTS

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    In Malaysia, studies on students with special needs in technical and vocational education are lacking. Therefore, this study aims to identify the level of readiness of trainee teachers towards the implementation of the teaching and learning process for technical and vocational subjects namely Design and Technology. This study uses a survey method using a 4-point Likert scale questionnaire as a research instrument involving a sample of 154 teacher trainees at the Technical Education Campus Teacher Education Institution who took the Design and Technology (RBT) course. The size of the selected respondents was by simple random sampling using Krejcie & Morgan's Sample Size Determination Table. Descriptive analysis was used to obtain the mean value, standard deviation, frequency, and percentage to see the level of preparedness of trainee teachers towards Special Needs Students (SNS) in TVET subjects. The findings of the study show the level of knowledge and skills of trainee teachers regarding the implementation of teaching and learning of Design and Technology subjects for students with Special Needs (SNS) which is overall at a moderate level. The results of the analysis found that the level of knowledge and skills of trainee teachers at Teacher Education Institutions concerning the implementation of the teaching and learning of Design and Technology subjects for Students with Special Needs (SNS) needs to be improved. This study is expected to provide input on the level of preparedness of trainee teachers at the Technical Education Campus Teacher Education Institution in teaching students with special educational needs in TVET subjects. Improving the knowledge and skills of Design and Technology trainee teachers at the Technical Education Campus Teacher Education Institution will have a positive impact on the effectiveness of the teaching and learning delivered by the trainee teachers, which in turn can improve the quality of learning for Special Needs Students (SNS) in the classroom. In conclusion, every trainee teacher needs to be given sufficient training and education to help Special Needs Students (SNS) in Design and Technology subjects

    Clinical analysis of insulin resistance in liver cirrhosis patients

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    Objective·To investigate the insulin resistance in liver cirrhosis patients.Methods·Patients with liver cirrhosis from Xinhua Hospital,Shanghai Jiao Tong University School of Medicine in 2013‒2017 were retrospectively assessed. Biochemical indexes, including fasting blood glucose (FBG), glycosylated hemoglobin A1c (HbA1c), fasting insulin and homeostatic model assessment-insulin resistance (HOMA-IR), were collected. The complications of liver cirrhosis were recorded, including esophagogastric varices bleeding (EVB), ascites and hepatic encephalopathy (HE). According to HOMA-IR value, the liver cirrhosis patients were divided into non-insulin resistance group (IR≤1.64) and insulin resistance group (IR>1.64). Various indicators were compared between the two groups.Results·A total of 376 patients with liver cirrhosis were included in this study. The proportions of Child-Pugh A, Child-Pugh B and Child-Pugh C were 162 (43.09%), 148 (39.36%), and 66 (17.55%), respectively. The main cause of liver cirrhosis was hepatitis B virus infection 163 (43.35%). Fasting insulin levels were measured in 208 of 376 liver cirrhosis patients. Among them, 117 patients (56.25%) had no insulin resistance and 91 patients (43.75%) had insulin resistance. The body mass index (BMI) of liver cirrhosis patients in the insulin resistance group was significantly higher than that in the non-insulin resistance group (P=0.000), and the prevalence of type 2 diabetes in the former was also higher (P=0.001). The scores of Child-Pugh in patients with liver cirrhosis in the insulin resistance group were lower than those in the non-insulin resistance group, and the difference in Child-Pugh score was statistically significant (6.93±1.99 vs 7.63±2.20, P=0.020). The proportion of Child-Pugh C grade in the insulin resistance group was significantly lower than that in the patients without insulin resistance (P=0.028). The prevalence of ascites in cirrhotic patients with insulin resistance was significantly lower than that in cirrhotic patients without insulin resistance (36.26% vs 66.67%, P=0.000). There was no significant difference in the prevalence of EVB and HE between the two groups (P>0.05).Conclusion·Nearly half of patients with liver cirrhosis are associated with insulin resistance. Compared with no-insulin resistance patients, cirrhotic patients with insulin resistance have a higher BMI, lower percentage of Child-Pugh C, and fewer ascites prevalence

    Lattice-based Public Key Encryption with Authorized Keyword Search: Construction, Implementation, and Applications

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    Public key encryption with keyword search (PEKS), formalized by Boneh et al. [EUROCRYPT\u27 04], enables secure searching for specific keywords in the ciphertext. Nevertheless, in certain scenarios, varying user tiers are granted disparate data searching privileges, and administrators need to restrict the searchability of ciphertexts to select users exclusively. To address this concern, Jiang et al. [ACISP\u27 16] devised a variant of PEKS, namely public key encryption with authorized keyword search (PEAKS), wherein solely authorized users possess the ability to conduct targeted keyword searches. Nonetheless, it is vulnerable to resist quantum computing attacks. As a result, research focusing on authorizing users to search for keywords while achieving quantum security is far-reaching. In this work, we present a novel construction, namely lattice-based PEAKS (L-PEAKS), which is the first mechanism to permit the authority to authorize users to search different keyword sets while ensuring quantum-safe properties. Specifically, the keyword is encrypted with a public key, and each authorized user needs to obtain a search privilege from an authority. The authority distributes an authorized token to a user within a time period and the user will generate a trapdoor for any authorized keywords. Technically, we utilize several lattice sampling and basis extension algorithms to fight against attacks from quantum adversaries. Moreover, we leverage identity-based encryption (IBE) to alleviate the bottleneck of public key management. Furthermore, we conduct parameter analysis, rigorous security reduction, and theoretical complexity comparison of our scheme and perform comprehensive evaluations at a commodity machine for completeness. Our L-PEAKS satisfies IND-sID-CKA and T-EUF security and is efficient in terms of space and computation complexity compared to other existing primitives. Finally, we provide two potential applications to show its versatility

    Isolation, characterization, and LC MS/MS determination of anti-obesity components from pine needles of Cedrus deodara (Roxb.) G. Don

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    ObjectiveThis study aimed to isolate and analyze the components in cedar pine needles (needle leaves of Cedrus deodara (Roxb.) G. Don) that exhibit anti-obesity effects, as determined through animal experiments.MethodsThe extract of cedar pine needles was separated into four fractions of different polarities using a macroporous resin column. The fraction that retained anti-obesity activity was evaluated based on the results of animal experiments. Monomeric compounds were structurally characterized and isolated from the active fraction using a preparative liquid chromatography system. Combined with subsequent glucose gel chromatographic separation. The content of the separated components was determined using ultrahigh performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-QQQ-MS/MS).ResultsThe water-washed fraction retained anti-obesity activity of the cedar pine needles more effectively. A total of 16 compounds were separated from this fraction, and the contents of 14 of these compounds were determined to be present in cedar pine needles.ConclusionNine components, namely p-hydroxy benzyl alcohol, chlorogenic acid, vanillic acid, syringic acid, P-coumaric acid, sinapic acid, benzoic acid, phenylacetic acid, salicylic acid, were characterized and determined for the first time in cedar pine needles. The components with anti-obesity activity in the pine needles of Cedrus are mainly derived from phenolic acids

    Crossover with the West: Tang Dynasty Chinese Fasion and Craftsmanship in Relationship to its Foreign Policies

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    This research was supported by the Undergraduate Research Opportunities Program (UROP)
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