Abstract
With the development of society, all fields will basically involve examinations. Nowadays, most of the papers in the form of paper media are used for examinations. The examination of paper ...media is heavily dependent on wasting natural resources and is difficult to improve effectiveness. For these reasons, the extensive use of test software is essential. The design and implementation of the text is based on the C/S mode exam management system. The system sets different permissions for each user category. People of different privileges use different functions. The system displays all the functions of the examination on the client, realizes the difference of information sharing and processing in real time, reduces the influence of human factors on the fairness of the examination, and greatly improves the efficiency of the examination.
This paper is a brief survey on the existing problems and challenges inherent in model-based control (MBC) theory, and some important issues in the analysis and design of data-driven control (DDC) ...methods are here reviewed and addressed. The necessity of data-driven control is discussed from the aspects of the history, the present, and the future of control theories and applications. The state of the art of the existing DDC methods and applications are presented with appropriate classifications and insights. The relationship between the MBC method and the DDC method, the differences among different DDC methods, and relevant topics in data-driven optimization and modeling are also highlighted. Finally, the perspective of DDC and associated research topics are briefly explored and discussed.
Abstract
The oil field enters the stage of ultra-high water cut development, especially after the third infilling, the well spacing is small. The water injection advances quickly, the water cut rises ...quickly, the control of natural decline becomes more and more difficult. According to the traditional oil field development management method, the oil field steady production difficulty will increase continuously. Therefore, we must constantly explore new methods of oilfield development to improve the quality and benefit of oilfield development.
The growth of white‐rot fungi is related to the superior infiltrability and biodegradability of hyphae on a lignocellulosic substrate. The superior biodegradability of fungi toward plant substrates ...affords tailored microstructures, which benefits subsequently high efficient carbonization and chemical activation. Here, the mechanism underlying the direct growth of mushrooms toward the lignocellulosic substrate is elucidated and a fungi‐enabled method for the preparation of porous carbons with ultrahigh specific surface area (3439 m2 g−1) is developed. Such porous carbons could have potential applications in energy storage, environment treatment, and electrocatalysis. The present study reveals a novel pore formation mechanism in root‐colonizing fungi and anticipates a valuable function for fungi in developing the useful porous carbons with a high specific surface area.
A universal fungi‐enabled method for the preparation of porous carbons with ultrahigh specific surface area for energy storage, adsorption, and electrocatalysis is developed. Hyphae infiltrate into the plant cell wall to secrete corresponding exoenzymes to generate a multidimensional framework, which is beneficial to the following carbonization and activation process.
We have developed a simple, one-step hydrothermal method for the synthesis of highly fluorescent carbon nanoparticles (F-CNPs) with a high quantum yield (68%) and good photostability. The method ...requires less reaction time and a lower reaction temperature as compared with the previous reported methods. The as-prepared F-CNPs exhibit excellent emission property and high stability, as well as excitation-independent emission behavior. Moreover, it is attractive that F-CNPs can be used as an effective fluorescent probe for the detection of mercury ions with good selectivity and sensitivity in an aqueous solution.
Metal–organic frameworks (MOFs) are regarded as promising materials for CO2 adsorption, which is an important step in CO2 electrochemical reduction. In this work, zeolitic imidazolate framework ...(ZIF‐8) nanomaterials were synthesized with various zinc sources and used as electrocatalysts for CO2 reduction to CO. Among them, ZIF‐8, prepared using ZnSO4, delivers the best catalytic activity towards CO2 electroreduction, with 65 % CO yield. The main catalytic center can be attributed to the discrete Zn nodes in ZIF‐8. Electrolytes are important in increasing the CO selectivity, and NaCl is the best suitable electrolyte due to facile anion exchange.
Zeolitic imidazolate frameworks (ZIF‐8) are synthesized using various zinc sources in aqueous solution. These materials are effective catalysts for electrochemical reduction of CO2, with CO as the major product. The roles of the electrolyte and Zn nodes are investigated in detail.
A biosimilar drug is defined in the US Food and Drug Administration (FDA) guidance document as a biopharmaceutical that is highly similar to an already licensed biologic product (referred to as the ...reference product) notwithstanding minor differences in clinically inactive components and for which there are no clinically meaningful differences in purity, potency, and safety between the two products. The development of biosimilars is a challenging, multistep process. Typically, the assessment of similarity involves comprehensive structural and functional characterization throughout the development of the biosimilar in an iterative manner and, if required by the local regulatory authority, an in vivo nonclinical evaluation, all conducted with direct comparison to the reference product. In addition, comparative clinical pharmacology studies are conducted with the reference product. The approval of biosimilars is highly regulated although varied across the globe in terms of nomenclature and the precise criteria for demonstrating similarity. Despite varied regulatory requirements, differences between the proposed biosimilar and the reference product must be supported by strong scientific evidence that these differences are not clinically meaningful. This review discusses the challenges faced by pharmaceutical companies in the development of biosimilars.
Biosimilars have the potential to provide lower cost alternatives and increase access to biologic medicines. Biosimilars are evaluated based on the “totality of evidence” including comprehensive analytical data, limited nonclinical studies, comparative clinical pharmacokinetic/pharmacodynamic, safety and efficacy data, to ensure patients receive high quality, safe and effective medicines. Kirchhoff and coworkers highlight the challenges faced during the development of biosimilars, and the range of state‐of‐the‐art analytical tools that are used to assess similarity.
Abstract The variation mechanism of blazars is a long-standing unresolved problem. In this work, we present a scenario to explain diverse variation phenomena for ON 231, where the jet emissions are ...composed of the flaring and the less variable components (most probably from the post-flaring blobs), and the variation is dominated by shock-in-jet instead of the Doppler effect. We perform correlation analysis for the multiwavelength light curves and find no significant correlations. For the optical band, ON 231 exhibits a harder when brighter (HWB) trend, and the trend seems to shift at different periods. Correspondingly, the correlation between the degree of polarization and flux exhibits a V-shaped behavior, and a similar translation relation during different periods is also found. These phenomena could be understood via the superposition of the flaring component and slowly varying background component. We also find that the slopes of the HWB trend become smaller at higher flux levels, which indicates the energy-dependent acceleration processes of the radiative particles. For the X-ray band, we discover a trend transition from HWB to softer when brighter (SWB) to HWB. We consider that the X-ray emission is composed of both the synchrotron tail and the synchrotron self-Compton components, which could be described by two log-parabolic functions. By varying the peak frequency, we reproduce the observed trend transition in a quantitative manner. For the γ -ray band, we find the SWB trend, which could be explained naturally if a very-high-energy γ -ray background component exists. Our study elucidates the variation mechanism of intermediate synchrotron-peaked BL Lac objects.
The pores of dodecahedron-like carbon frameworks derived from metal–organic frameworks (MOFs) were in situ expanded via a surfactant-template strategy, which were originally demonstrated to enhance ...capacitive deionization (CDI). The dodecahedron-like carbon frameworks were obtained through carbonization of zeolitic imidazolate framework-8 (ZIF-8) using the cetyltrimethylammonium bromide as a supramolecular template. It is found that the dodecahedron-like carbon frameworks derived from ZIF-8 possess efficiently expanded pores while retaining the original morphology and high nitrogen contents. Compared to those of the normal ZIF-8-derived carbon, the obtained materials exhibit a hierarchically porous structure with a higher specific surface area and an improved pore volume. Electrochemical studies of the obtained electrode demonstrate that this material has a high specific capacitance and lower inner resistance. More importantly, the obtained material shows a higher salt adsorption capacity (20.05 mg/g) than the normal ZIF-8-derived carbon (13.01 mg/g). Furthermore, the obtained electrode presents a rapid salt removal rate and excellent cycling stability. The significantly enhanced deionization behavior of the obtained materials is due to the combination effect of its large accessible surface area, large pore volume, and rich nitrogen doping. The results reveal that in situ expanding pores of carbon frameworks derived from MOFs is an ideal way for constructing electrode materials with enhanced CDI performance. The present work may pave a path for the design and development of highly efficient MOF-derived electrode materials.
With the rapid development of market economy, the task scheduling model has become the core problem in the field of corporate management. In order to solve the problem that the stability of the model ...will decline due to the interference of human factors in the process of multitask scheduling in the traditional algorithm, a reasonable scheduling model based on the priority principle is proposed in this paper. This paper expounds the principle of multitask scheduling in company management, constructs a multitask scheduling network model based on priority, performs virtual scheduling on the model, searches the optimal solution in the solution space of the scheduling problem, and obtains the reasonable multitask scheduling method in the company management. Through the analysis of relevant simulation experiments, it can be concluded that the task scheduling algorithm proposed in this paper can not only allocate the corresponding resources for high-priority tasks effectively, but also can save the cost, so as to show better execution efficiency.
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