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51.
52.
詹涛 《吉林水利》2021,(10):58-61
针对临近水库的别墅等建筑物的清查整治,在实体层面,尤其对于五证齐全的建筑物,如何定性为违建需要慎重把握,对水库管理范围的界定是一个重点问题;在程序层面,应避免执法中因急于求成而催生的程序违法.强拆行为会产生重大损失,涉及多方主体和多重法律关系,应理清其中各方的法律责任,妥善解决纠纷.  相似文献   
53.
Lu  Qiang  Tao  Fan  Zhou  Shuo  Wang  Zhiguang 《Neural computing & applications》2021,33(14):8495-8511
Neural Computing and Applications - Most traditional genetic programming methods that handle symbolic regression are random algorithms without memory and direction. They repeatedly search for the...  相似文献   
54.
Many video service sites headed by YouTube know what content requires copyright protection. However, they lack a copyright protection system that automatically distinguishes whether uploaded videos contain legal or illegal content. Existing protection techniques use content-based retrieval methods that compare the features of video. However, if the video encoding has changed in resolution, bit-rate or codec, these techniques do not perform well. Thus, this paper proposes a novel video matching algorithm even if the type of encoding has changed. We also suggest an intelligent copyright protection system using the proposed algorithm. This can serve to automatically prevent the uploading of illegal content. The proposed method has represented the accuracy of 97% with searching algorithm in video-matching experiments and 98.62% with automation algorithm in copyright-protection experiments. Therefore, this system could form a core technology that identifies illegal content and automatically excludes access to illegal content by many video service sites.  相似文献   
55.
In this paper we have proposed a dynamic pricing scheme for the contributing peers in the Video on Demand (VoD) system. The scheme provides an effective mechanism to maximize the profit through the residual resources of the contributing peers. A utilization function is executed for each contributing peer to estimate the utility factor based on the parameters such as initial setup cost, holding cost, chaining cost and salvage cost. In this paper, we urge an effective dynamic pricing algorithm that efficiently utilizes a range of parameters with a varying degree of complexity. The key findings of the algorithm are (i) each contributing peers are benefitted by the monetary based on its resource contributions to the VoD system and (ii) a high degree of social optimum is established by proficiently aggregating the contributing peer’s resources with the overall resources of the VoD system. We validate our claim by simulating the proposed dynamic pricing scheme with other standard pricing schemes such as altruism, cost model and game theory perspective. The result of our dynamic pricing scheme shows the best utility factor than other standard pricing schemes.  相似文献   
56.
The paper is concerned with the stability of linear systems with interval time-varying delay. Through constructing a new augmented Lyapunov-Krasovskii functional (LKF) which contains some quadruple-integral terms and estimating the time derivative of the LKF less conservatively, new stability criteria are derived without introducing any free matrices. Moreover, by proving the positive definiteness of the LKF with some integral inequalities, the constraints on some functional parameters are relaxed and the conservatism of the obtained results are further reduced. Numerical examples are also given to demonstrate the effectiveness and reduced conservatism of the obtained results.  相似文献   
57.
本文研制了一台测量电子束和β射线吸收剂量的外推电离室,其空腔室壁材料可拆换并分别与空气、组织和硅等效,收集电极名义直径为1.5、3、10和30mm,空气空腔可变范围为0.2~15mm。该外推电离室具有在空腔内部测温,自动改变窗口上方材料厚度及采用微型计算机控制等特点。适用于测10 MeV能量以下,剂量率为10~5~10~(-3)Gy/h的电子或β射线吸收剂量。整个外推电离室自动测剂量系统在测~(204)TLβ放射源表面剂量率的不确定度为2.3%。测1.5 MeV电子束在硅和哈密瓜深部剂量率时,不确定度分别为4.0%和2.8%。  相似文献   
58.
TiO2是较为成熟的半导体光催化材料,但因TiO2分散性差、量子利用率低、比表面积小、难回收等问题难以工业化.多孔金属有机框架(MOFs)的引入可增强TiO2/MOFs复合材料的光吸收性能,提高电子-空穴对分离效率和提高回收率.基于TiO2/MOFs制备时前驱体添加顺序不同,综述了TiO2/MOFs的3种制备方法(即Ship-in-a-bottle法、Bottle-around-ship法、One-pot法)及TiO2/MOFs光催化机理与性能影响因素,并探讨不同MOFs与TiO2结合的作用机理.最后,对TiO2/MOFs存在的问题提出建议.  相似文献   
59.
Distortion as a result of the quenching process is predominantly due to the thermal gradient and phase transformations within the component. Compared with traditional liquid quenching, the thermal boundary conditions during gas quenching are relatively simple to control. By adjusting the gas-quenching furnace pressure, the flow speed, or the spray nozzle configuration, the heat-transfer coefficients can be designed in terms of both the component geometry and the quenching time. The purpose of this research is to apply the optimization methodology to design the gas-quenching process. The design objective is to minimize the distortion caused by quenching. Constraints on the average surface hardness, and its distribution and residual stress are imposed. The heat-transfer coefficients are used as design variables. DEFORM-HT is used to predict material response during quenching. The response surface method is used to obtain the analytical models of the objective function and constraints in terms of the design variables. Once the response surfaces of the objective and constraints are obtained, they are used to search for the optimum heat-transfer coefficients. This process is then used instead of the finite-element analysis. A one-gear blank case study is used to demonstrate the optimization scheme.  相似文献   
60.
张涛  高永军 《铸造技术》2005,26(7):605-606
针对大型薄壁铝铸件内腔表面出现的沟槽缺陷,从差压铸造、树脂砂、铸件结构等工艺条件方面探讨了产生的机理,并通过试验和对比研究,确定排气不畅是该缺陷的首要引发因素,找到了消除该缺陷的工艺方法,提出了相关预防措施,避免了因此产生的废品损失.  相似文献   
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