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排序方式: 共有934条查询结果,搜索用时 500 毫秒
921.
Cloud computing has appeared as a technology allowing a company to employ computing resources such as applications, software, and hardware to calculate over the Internet. Scholars have paid great attention to cloud computing because of its cutting-edge availability, cost decrement, and boundless applications. A cloud database is a data storage site on the web where the optimal path is spotted to access the needed database. So, placing the ideal path to a database is crucial. The cloud database defined the scheduling problem to choose the perfect route. Cloud database path scheduling is a multifaceted procedure consisting of congestion control, routing list, and network flow distribution. It has a postponement in searching for the needed source route from the cloud database. Offering numerous infinite resources with the growing database workload is an NP-Hard optimization problem where the query request needs optimal schedules to respond to the required services. So, we have used a hybrid cuckoo search (CS) and genetic algorithm (GA), motivated by a social bird's phenomenon, to solve this problem. Integrating genetic operators has dramatically enhanced the balance between the capability of searching and utilization.  相似文献   
922.
Journal of Inorganic and Organometallic Polymers and Materials - The modification of graphene oxide (GO) with octadecylamine was performed to emulsify dimethyl formamide droplets in octane via...  相似文献   
923.
Many organizations have insisted on protecting the cloud server from the outside, although the risks of attacking the cloud server are mostly from the inside. There are many algorithms designed to protect the cloud server from attacks that have been able to protect the cloud server attacks. Still, the attackers have designed even better mechanisms to break these security algorithms. Cloud cryptography is the best data protection algorithm that exchanges data between authentic users. In this article, one symmetric cryptography algorithm will be designed to secure cloud server data, used to send and receive cloud server data securely. A double encryption algorithm will be implemented to send data in a secure format. First, the XOR function will be applied to plain text, and then salt technique will be used. Finally, a reversing mechanism will be implemented on that data to provide more data security. To decrypt data, the cipher text will be reversed, salt will be removed, and XOR will be implemented. At the end of the paper, the proposed algorithm will be compared with other algorithms, and it will conclude how much better the existing algorithm is than other algorithms.  相似文献   
924.
Clean Technologies and Environmental Policy - Biomass as an abundant renewable energy source can play a vital role in controlling the greenhouse gas emissions. The distributed nature of biomass and...  相似文献   
925.
“Organoid medicine” has rapidly progressed over the past decade as a new class of therapeutics with high functionality and complexity for addressing unmet medical needs such as effective treatment of patients suffering from chronic liver disease using liver organoids. Here, scalable and xeno-free integrated differentiation platforms are established to generate hepatic progenitors, mesenchymal stromal cells, and endothelial cells using individual human pluripotent stem cell lines as starting cell types for vascularized liver organoids generation. A scalable microfluidic system is developed to continuously generate cells-loaded microcapsules with self-biodegradable 4-arm-PEG-MMP1-sensitive peptide hydrogel as shell material, to support cells proliferation, self-condensation, and liver organoids generation through self-organization. Self-organized vascularized hepatobiliary organoids (VHOs) containing interconnected biliary networks and vascular structures are generated after optimizing the co-culture conditions inside hydrogel microcapsules and transferring the organoids to 3D dynamic suspension culture for further maturation. The VHOs show key functional features similar to the fetal and adult liver tissue including the expression of liver-specific marker genes, the ability to perform main liver metabolic functions, and inducing drug metabolism. The established platforms can be beneficial to the mass production of human liver organoids for liver organoid medicine and the development of safe, effective, and personalized drugs.  相似文献   
926.
In the current paper, the effect of a magnetic field on the fully developed forced convective flow and heat transfer is studied. An exact solution is extracted when the flow in the porous medium is governed by the Brinkman–Forchheimer Extended Darcy model. First, the problem formulation is explained to obtain a new system of mathematical formulation. Then, by utilizing the properties which are imposed into the problem, the exact closed-form analytical solution of the problem is explored. Finally, the main results are illustrated to show the impact of the porous media-shaped parameter, magnetic parameter, Forchheimer number, and viscosity ratio. It should be mentioned that the asymptotic results achieved in this study were compared with the exact results and it is found that they are in good agreement.  相似文献   
927.
We investigated the Ruddlesden-Popper series CaO(CaMnO3)m with m = 1, 2, 3, ∞, to study the impact of the varying amounts of CaO layers on their thermoelectric properties. Previous studies showed that highly dense samples are difficult to obtain due to the refractory nature of these materials. In this study, we managed to obtain dense pellets during a classical hot-pressing step, if and only if the samples were subjected to extended ball-milling prior to pressing, resulting in crystallite sizes of 30–35 nm after hot-pressing. The sample with the largest amount of CaO layers (m = 1) had the lowest electrical and thermal conductivity, and the highest Seebeck coefficient, as predicted. Ultimately the perovskite CaMnO3 (m = , no CaO layers) exhibited the best thermoelectric properties.  相似文献   
928.
929.
Journal of Mechanical Science and Technology - Understanding heat transfer characteristics of sheet metal is of practical importance in sheet metal rolling operation to ensure strength and quality...  相似文献   
930.
Mehrdad  Farzad  Ahangari  Zahra 《SILICON》2022,14(13):7567-7576
Silicon - In this paper, we comprehensively assess the unique features, feasibility and limitations of dual material gate fin field effect transistor for tuning the threshold voltage in nanoscale...  相似文献   
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