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Flexural failure experiment on cracked PC simply supported box girders 被引量:1
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作者 CAO Guo-hui ZHANG Wang +1 位作者 PENG Xi-rong ZHANG Sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第11期2685-2692,共8页
Long-term load and flexural failure experiments are carried out on two prestressed concrete(PC) simply supported box girders. In the long-term load experiment, girder-1(G1) is in an elastic state, while girder-2(G2) i... Long-term load and flexural failure experiments are carried out on two prestressed concrete(PC) simply supported box girders. In the long-term load experiment, girder-1(G1) is in an elastic state, while girder-2(G2) is in a cracking state. To investigate the influence of cracking on the flexural behaviors of PC simply supported box beams, the experiment results are analyzed from many aspects, such as load–deflection, load–strain, and failure mode. Experiment results show the following: 1) the shrinkage and creep of concrete have considerable influences on the long-term deflection and strain of the two girders; 2) in the flexural failure experiment, the cracks and ultimate loads of the two girders are close. The rigidity degeneration of G2 is significantly faster than that of G1, and thus G2 shows nonlinear characteristics earlier; 3) to prove the validity and rationality of the current code, the cracking load and ultimate load of the two girders are calculated according to the current code. 展开更多
关键词 PC box girders long-term load experiment flexural behaviors cracks static performance
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POLAR Experiment Reveals Orderly Chaos of Black Holes
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作者 IHEP 《Bulletin of the Chinese Academy of Sciences》 2018年第4期210-212,共3页
An international consortium of scientists studying gamma-ray bursts (GRBs) as part of the POLAR (GRB polarimeter) experiment has revealed that high-energy photon emissions from black holes are neither completely chaot... An international consortium of scientists studying gamma-ray bursts (GRBs) as part of the POLAR (GRB polarimeter) experiment has revealed that high-energy photon emissions from black holes are neither completely chaotic nor completely organized, but a mixture. 展开更多
关键词 POLAR experiment REVEALS black HOLES GRB
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基于Cruise/BlackBox的电动汽车制动能量回收仿真 被引量:2
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作者 余楚礼 辛明华 《汽车工程师》 2016年第5期25-27,共3页
在使用AVL-Cruise进行整车仿真过程中,需要对制动能量回收策略进行研究。基于AVL-Cruise建立仿真平台,使用Cruise/Black Box引入控制代码,设定一个制动能量回收策略并使用Cruise/Black Box实现控制策略,使用AVL-Cruise联合Cruise/Black ... 在使用AVL-Cruise进行整车仿真过程中,需要对制动能量回收策略进行研究。基于AVL-Cruise建立仿真平台,使用Cruise/Black Box引入控制代码,设定一个制动能量回收策略并使用Cruise/Black Box实现控制策略,使用AVL-Cruise联合Cruise/Black Box接口组件对具体的工况进行仿真分析。结果表明,基于Cruise/Black Box的电动汽车制动能量回收仿真,能够完全真实地反映制动能量回收控制策略在电动汽车上的工作过程。 展开更多
关键词 电动汽车 Cruise/black box 制动能量回收
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Analysis of Data on Xanthan Fermentation in Stationary Phase Using Black Box and Metabolic Network Models 被引量:2
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作者 马红武 赵学明 唐寅杰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1999年第4期321-325,共5页
The xanthan fermentation data in the stationary phase was analyzed using the black box and the metabolic network models. The data consistency is checked through the elemental balance in the black box model. In the met... The xanthan fermentation data in the stationary phase was analyzed using the black box and the metabolic network models. The data consistency is checked through the elemental balance in the black box model. In the metabolic network model, the metabolic flux distribution in the cell is calculated using the metabolic flux analysis method, then the maintenance coefficients is calculated. 展开更多
关键词 xanthan fermentation black box model metabolic flux analysis maintenance coefficients
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Did LIGO Really Detect Gravitational Waves?—The Existence of Electromagnetic Interaction Made the Experiments of LIGO Invalid 被引量:4
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作者 Xiaochun Mei Ping Yu 《Journal of Modern Physics》 2016年第10期1098-1104,共7页
The paper proves that due to the existence of electromagnetic interaction, the experiments of LIGO cannot detect gravitational waves. This is also the reason why Weber’s experiments of gravitational waves failed. In ... The paper proves that due to the existence of electromagnetic interaction, the experiments of LIGO cannot detect gravitational waves. This is also the reason why Weber’s experiments of gravitational waves failed. In fact, the formulas of general relativity that gravitational waves affect distances are only suitable for particles in vacuum. LIGO experiments are carried out on the earth. The laser interferometers are fixed on the steel pipes on the earth’s surface in the balanced state of electromagnetic force. Electromagnetic force is 10<sup>40</sup> times greater than gravity. Gravitational waves are too weak to overcome electromagnetic force and change the length of steel pipes. Without considering this factor, the design principle of LIGO experiment has serious problem. The experiments to detect gravitational waves should move to space to avoid the influence of electromagnetic interaction. Besides, LIGO experiments have the following problems. 1) No explosion source of gravitational waves is really founded. 2) The argument that the Einstein’s theory of gravity is verified is a vicious circle and invalid in logic. 3) The results of experiments cause sharp contradiction for the energy currents of gravitational waves. The difference reaches to 10<sup>24</sup> times and is unacceptable. 4) The method of numerical relativity causes great errors due to the existence of singularities. The errors are enlarged by the effect of butterfly due to the non-linearity of Einstein’s equation of gravity. 5) The so-called change of length 10<sup>-18</sup> m between two glasses of interferometers detected in the experiment exceeds the ability of current technique. This kind of precise has entered micro-scalar. The uncertain principle of quantum mechanics makes it impossible. The signs appeared in LIGO experiments are not caused by distance change. 6) LIGO experiments have not detected gravitational waves. What detected may be the signs of disturbances coming from the middle region between two laser interferometers. 展开更多
关键词 LIGO experiments Gravitational Waves General Relativity Electromagnetic Interaction Laser Interferometer Weber experiment Singularity black Holes
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Reliable Space Pursuing for Reliability-based Design Optimization with Black-box Performance Functions 被引量:2
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作者 SHAN Songqing WANG G Gary 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第1期27-35,共9页
Reliability-based design optimization (RBDO) is intrinsically a double-loop procedure since it involves an overall optimization and an iterative reliability assessment at each search point. Due to the double-loop pr... Reliability-based design optimization (RBDO) is intrinsically a double-loop procedure since it involves an overall optimization and an iterative reliability assessment at each search point. Due to the double-loop procedure, the computational expense of RBDO is normally very high. Current RBDO research focuses on problems with explicitly expressed performance functions and readily available gradients. This paper addresses a more challenging type of RBDO problem in which the performance functions are computation intensive. These computation intensive functions are often considered as a "black-box" and their gradients are not available or not reliable. On the basis of the reliable design space (RDS) concept proposed earlier by the authors, this paper proposes a Reliable Space Pursuing (RSP) approach, in which RDS is first identified and then gradually refined while optimization is performed. It fundamentally avoids the nested optimization and probabilistic assessment loop. Three well known RBDO problems from the literature are used for testing and demonstrating the effectiveness of the proposed RSP method. 展开更多
关键词 Reliability based design optimization black-box function reliable design space
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Box-Behnken响应面法优化羟基红花黄色素A纳米粒处方工艺及体外释放评价 被引量:1
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作者 肖奕菲 杜利新 +3 位作者 魏起东 陆慧玲 郭志华 李雅 《中药新药与临床药理》 CAS CSCD 北大核心 2024年第1期122-131,共10页
目的优化羟基红花黄色素A(hydroxysafflor yellow A,HSYA)纳米粒制备工艺,并对其进行体外释放评价。方法以乳酸-羟基乙酸共聚物[poly(lactic-co-glycolicacid),PLGA]为载体,利用改良的复乳法制备HSYA纳米粒,通过Plackett-Burman设计实... 目的优化羟基红花黄色素A(hydroxysafflor yellow A,HSYA)纳米粒制备工艺,并对其进行体外释放评价。方法以乳酸-羟基乙酸共聚物[poly(lactic-co-glycolicacid),PLGA]为载体,利用改良的复乳法制备HSYA纳米粒,通过Plackett-Burman设计实验联用Box-Behnken响应面法优选最佳制备工艺;利用粒径测定仪、TEM扫描电镜仪、傅里叶红外光谱(FT-IR)仪、X-射线粉末衍射(XRD)仪对纳米粒进行表征;并对其进行4℃储藏稳定性、生理介质中稳定性、冻干保护剂及体外释放率考察。结果优选出纳米粒最佳工艺处方为:pH为6.95,投药量为2.8 mg,载体用量为18.2 mg;在此条件下制备出的纳米粒粒径为(176.4±1.29)nm,多分散系数(Polydiseperse Index,PDI)为(0.152±0.014),Zeta电位为(-17.6±0.46)mV,包封率为(78.5±0.49)%,载药量为(7.3±0.07)%,纳米粒形态圆整,分散性好;在4℃储存环境下、不同生理介质中稳定性良好,最佳冻干保护剂为1%葡萄糖;纳米粒48 h体外释放率为85%。结论该优化方法合理可靠,所得纳米粒稳定性良好,具有一定的缓释作用,体外释放符合一级动力学模型。 展开更多
关键词 羟基红花黄色素A PLGA纳米粒 Plackett-Burman设计实验 box-Behnken响应面法 体外释放
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Application of ″Black Box″ to fault diagnosis of rotating machine 被引量:1
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作者 张金祥 徐敏强 +2 位作者 黄文虎 张佳莺 张国斌 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第1期83-86,共4页
Presents the navigation based on reinforcement learning and an algorithm, and disscusses the combination of the neural network with Q learning.
关键词 reinforcement learning neural network robot navigation
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Black Box Modeling Method and Its Application in Refractories Techniques
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作者 WANG Jiezeng YUAN Lin YE Yahong LI Penghai WANG Juntao 《China's Refractories》 CAS 2012年第4期1-6,共6页
Concept of black box, condition of modeling and control methods were introduced. Taking high purity silica brick as an example, the silica brick featured with high purity, low porosity, low true density and high stren... Concept of black box, condition of modeling and control methods were introduced. Taking high purity silica brick as an example, the silica brick featured with high purity, low porosity, low true density and high strength was developed through problem analysis, test design, modeling and optimization. Using information technology to upgrade refractories industry was discussed. 展开更多
关键词 black box MODELING OPTIMIZATION TECHNIQUES REFRACTORIES
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A Novel Black Box Based Behavioral Model of Power Amplifier for WCDMA Applications
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作者 Amandeep Singh Sappal Manjeet Singh Patterh Sanjay Sharma 《Communications and Network》 2010年第3期162-165,共4页
In this paper, Black Box approach is presented for behavioral modeling of a non linear power amplifier with memory effects. Large signal parameters of a Motorola LDMOS power amplifier driven by a WCDMA signal were ext... In this paper, Black Box approach is presented for behavioral modeling of a non linear power amplifier with memory effects. Large signal parameters of a Motorola LDMOS power amplifier driven by a WCDMA signal were extracted while taking into considerations the power amplifier’s bandwidth. The proposed model was validated based on the simulated data. Some validation results are presented both in the time and frequency domains, using WCDMA signal. 展开更多
关键词 BEHAVIORAL Model black box Power AMPLIFIERS
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Operating room black box:Scrutinizer of theatre practices
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作者 Prem Kumar A PI Pragyan Pratik Nithya Ravichandran 《Laparoscopic, Endoscopic and Robotic Surgery》 2023年第4期142-146,共5页
Objective:Adverse surgical events are a major cause of morbidity,mortality,and disability worldw ide.The cause of many such events can be attributed to interruptions in the operating room(OR),muli-tasking by surgeons,... Objective:Adverse surgical events are a major cause of morbidity,mortality,and disability worldw ide.The cause of many such events can be attributed to interruptions in the operating room(OR),muli-tasking by surgeons,etc.The objective of this study was to observe the types and frequency of intra-operative wor kflow interruptions in our ORs.Method:This ccoss-sectional study was conducted from March Do April of 2023.An observational approach using an audio-video recording device was employed to record OR flow disr uptions.One elective OR and one emergency OR under the Department of General Surgery were selected for the study.All open and laparoscopic surger ies conducted in the selected ORs were included.An Internet Protocol camera'was installed in the selec ted ORS with a view of the entire room,including the anesthesia station.Audio-video recording was started after the first indsion and stopped after closure of the surgical site.Result:Of the 51 cases that were studied,45(88.2%)were elective,and 18(35.3%)were laparoscopic cases.They could be classified into 8 types of open procedures and 4 types of lapar oscopic procedures.The mean maximum headcount inside the OR was 15.5土3.6 and doors opened on average of 15.8土6.0 times during a procedure.Other interruptions were surgeons attending phone calls(24,47.1%),leaving the sterile area(21,41.2%),technical disturbances(32,62.7%),anesthetic interruptions(18,35.3%),and faulty instruments(29,56.9%)Elective procedures had a signifcandy higher average number of in-terruptions per operating hour than emergency procedures(175±8.6vs.7.1±2.9,p<0.01).Condusion:Preventable factors such as faulty instruments,anesthetic interruption,and attending phone calls by the surgeon are commonly observed in ORs.They need to be addressed by timely surgical audits or the adoption of continued sureillance methods that can help take measures to minimize their occurrence. 展开更多
关键词 INTERRUPTION black box CAMERA Surgical audit Operation theatre
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Cultivation of Modern and New Farmers from the Perspective of Black Box of Science and Technology
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作者 CHEN Shou-zhu 《Asian Agricultural Research》 2012年第6期50-53,共4页
On the basis of analyzing the connotation and function of black box of science and technology,this article expounds the necessity of cultivating modern and new farmers in China at present,and points out that with ince... On the basis of analyzing the connotation and function of black box of science and technology,this article expounds the necessity of cultivating modern and new farmers in China at present,and points out that with incessant progress of science and technology,the modern agriculture based on black box of science and technology will continue to grow,which requires a large number of new farmers who can learn and improve black box of agricultural science and technology.Finally,the recommendations are put forward for cultivation of new farmers:improving farmers' training system;enhancing rural financial support,so that the farmers benefit from black box of science and technology;strengthening the cultivation of the practical ability,and promoting farmers' management capacity;strengthening the cultivation of innovative ability,and nurturing innovative farmers. 展开更多
关键词 black box of science and technology New farmers CULTIVATION
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Electric power generation technology of natural gas pressure reduction:Insights from black box-gray box hierarchical exergy analysis and evaluation method
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作者 Zhi-Dong Li Qing-Lin Cheng +4 位作者 You-Wang Chen Jiang-Dong Wei Li-Li Lv Hao Wu Yang Liu 《Petroleum Science》 SCIE CAS CSCD 2022年第1期329-338,共10页
Based on the“three box”exergy analysis model,a black box-gray box hierarchical exergy analysis and evaluation method is put forward in this paper,which is applied to evaluate the power generation technology of diffe... Based on the“three box”exergy analysis model,a black box-gray box hierarchical exergy analysis and evaluation method is put forward in this paper,which is applied to evaluate the power generation technology of differential pressure produced by natural gas expansion.By using the exergy analysis theory,the black box-gray box hierarchical exergy analysis models of three differential pressure power generation technologies are established respectively.Firstly,the“black box”analysis models of main energy consuming equipment are established,and then the“gray box”analysis model of the total system is established.Based on the calculation results of exergy analysis indexes,the weak energy consumption equipment in the whole power generation process is accurately located.Taking a gas field in southwest China as an example,the comprehensive energy consumption evaluation of the three power generation technologies is carried out,and the technology with the best energy consumption condition among the three technologies is determined.Finally,the rationalization improvement measures are put forward from improving the air tightness,replacing the deflector and reducing the flow loss. 展开更多
关键词 Expansion differential pressure power generation black box-gray box hierarchy Exergy analysis method Weak link of energy consumption
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Box-Behnken响应面法优化“五味子-吴茱萸”药对的提取工艺及含量测定 被引量:1
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作者 庞成国 韩华 董培良 《中医药导报》 2024年第6期39-43,78,共6页
目的:优化“五味子-吴茱萸”药对提取工艺并测定其不同配伍的化学成分含量。方法:利用Box-Behnken设计在单因素考察的基础上考察“五味子-吴茱萸”药对的提取工艺,确定最佳提取工艺,并通过高效液相色谱法测定“五味子-吴茱萸”的化学含... 目的:优化“五味子-吴茱萸”药对提取工艺并测定其不同配伍的化学成分含量。方法:利用Box-Behnken设计在单因素考察的基础上考察“五味子-吴茱萸”药对的提取工艺,确定最佳提取工艺,并通过高效液相色谱法测定“五味子-吴茱萸”的化学含量,确定药对的最佳比例。结果:“五味子-吴茱萸”药对最优提取工艺为乙醇体积分数70%,料液比1∶15(g/mL),提取时间60 min,提取次数3次。该提取工艺科学可靠。结论:本研究方法简单可行,可为“五味子-吴茱萸”药对的开发利用及相关研究提供参考。 展开更多
关键词 五味子 吴茱萸 药对 提取工艺 单因素试验 box-Behnken响应面试验 含量测定
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Exploring Image Culture Through Narrative: A Study on Jennifer Egan's Twitter Fiction Black Box
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作者 NIE Bao-yu 《Journal of Literature and Art Studies》 2015年第10期820-829,共10页
Notable for the completeness with which it surrenders formally and artistically to the textual dictates of Twitter, Jennifer Egan's 2012 short science fiction Black Box is one of the most triumphant and fully-fledged... Notable for the completeness with which it surrenders formally and artistically to the textual dictates of Twitter, Jennifer Egan's 2012 short science fiction Black Box is one of the most triumphant and fully-fledged fictions written in the form of new media. This paper explores the Twitter narrative employed in Black Box, pointing out that the serialized tweeting format of the story released via computer, mobile phone, or other electronic equipments brings readers immediate reading experience, allowing readers to sense the same feelings as the protagonist does. Through the experimental serialization of"Twitter" narrative, Egan expresses her concerns and worries about the security of the American security as well as the whole world in the post-"9.11" period and at the same time she embraces the virtues and pleasures of traditional storytelling delivered through a wholly new digital format. This paper concludes that Black Box is perhaps one of the boldest experiments of narrative form and is direct exploration into the contemporary image culture. 展开更多
关键词 Jennifer Egan black box Twitter narrative image culture
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The Black Box
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作者 单祝堂 《语言教育》 1996年第6期37-39,共3页
Like many other people ~*with nowhere better to go^1,thewoman everyone called Old Betty came to the library almost everyday.Prim^2 Miss Tonsitt sometimes had to get the caretaker^3 to e-ject^4 old people from the libr... Like many other people ~*with nowhere better to go^1,thewoman everyone called Old Betty came to the library almost everyday.Prim^2 Miss Tonsitt sometimes had to get the caretaker^3 to e-ject^4 old people from the library if their sleeping,eating or talkingbecame too objectionable^5,but Old Betty never gave any trouble.Still quite sprightly^6 despite her age, ~*though subiect to 展开更多
关键词 TROUBLE SOMETIMES EVERYONE EVERYDAY library NEVER EATING The black box Still think
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On the Effectiveness of the System Validation Based on the Black Box Testing Methodology
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作者 Dusica Marijan Nikola Teslic +1 位作者 Miodrag Temerinac Vukota Pekovic 《Journal of Electronic Science and Technology of China》 2009年第4期385-389,共5页
With the advancement of technology in recent years, effective fault diagnosis became a necessity to verify the performance and ensure the quality of complex systems. In this paper, an original verification methodology... With the advancement of technology in recent years, effective fault diagnosis became a necessity to verify the performance and ensure the quality of complex systems. In this paper, an original verification methodology for complex consumer electronic devices is presented. Verification of the system which consists of hardware (integrated circuit) and corresponding software within a flat panel TV set is in the focus. Proposed methodology provides reliable functional failure detection using the concept of black box testing. Further, the approach is fully automated, improving the reliability and speed of failure detection. The methodology effectiveness has been experimentally evaluated and the analysis results have been reported. 展开更多
关键词 Automated verification black box testiug system failure detection system fault diagnosis.
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Box-Behnken响应面法结合BP神经网络优化黑胡椒脐贴处方研究 被引量:1
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作者 程索婷 黄莉 +3 位作者 邹纯才 鄢海燕 任佩 王紫彤 《安徽中医药大学学报》 CAS 2024年第3期93-99,共7页
目的采用Box-Behnken响应面法结合BP神经网络优化黑胡椒脐贴处方。方法在前期预试验的基础上,以载药量、促渗剂用量、聚乙二醇(polyethylene glycol,PEG)6000与微粉硅胶的比例为影响因素,进行单因素试验。结合体外透皮试验,利用高效液... 目的采用Box-Behnken响应面法结合BP神经网络优化黑胡椒脐贴处方。方法在前期预试验的基础上,以载药量、促渗剂用量、聚乙二醇(polyethylene glycol,PEG)6000与微粉硅胶的比例为影响因素,进行单因素试验。结合体外透皮试验,利用高效液相色谱法测定胡椒碱的含量,对胡椒碱峰面积、指纹图谱的总峰面积和脐贴的成型性、剥离残留度和基质填充情况赋以权重,所得结果为综合评价指标。在单因素试验的基础上利用Box-Behnken响应面法结合BP神经网络优化脐贴处方。结果黑胡椒脐贴的最佳处方为载药量7%、氮酮4.5%、PEG6000与微粉硅胶的质量比为43∶1。结论黑胡椒脐贴的处方合理,可为后续贴剂的药效学研究提供基础。 展开更多
关键词 黑胡椒 脐贴 box-Behnken响应面法 BP神经网络
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<i>PP</i>and <i>P<span style='text-decoration:overline;'>P</span></i>Multi-Particles Production Investigation Based on CCNN Black-Box Approach
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作者 El-Sayed A. El-Dahshan 《Journal of Applied Mathematics and Physics》 2017年第6期1398-1409,共12页
The multiplicity distribution (P(nch)) of charged particles produced in a high energy collision is a key quantity to understand the mechanism of multiparticle production. This paper describes the novel application of ... The multiplicity distribution (P(nch)) of charged particles produced in a high energy collision is a key quantity to understand the mechanism of multiparticle production. This paper describes the novel application of an artificial neural network (ANN) black-box modeling approach based on the cascade correlation (CC) algorithm formulated to calculate and predict multiplicity distribution of proton-proton (antiproton) (PP and PP ) inelastic interactions full phase space at a wide range of center-mass of energy . In addition, the formulated cascade correlation neural network (CCNN) model is used to empirically calculate the average multiplicity distribution nch> as a function of . The CCNN model was designed based on available experimental data for = 30.4 GeV, 44.5 GeV, 52.6 GeV, 62.2 GeV, 200 GeV, 300 GeV, 540 GeV, 900 GeV, 1000 GeV, 1800 GeV, and 7 TeV. Our obtained empirical results for P(nch), as well as nch> for (PP and PP) collisions are compared with the corresponding theoretical ones which obtained from other models. This comparison shows a good agreement with the available experimental data (up to 7 TeV) and other theoretical ones. At full large hadron collider (LHC) energy ( = 14 TeV) we have predicted P(nch) and nch> which also, show a good agreement with different theoretical models. 展开更多
关键词 Proton-Proton and Proton-Antiproton Collisions Multiparticle PRODUCTION Multiplicity Distributions Intelligent Computational Techniques CCNN-Neural Networks black-box Modeling Approach
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Black Hole Complementarity in Terms of the Outsider and Insider Perspectives
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期184-192,共9页
A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation... A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation of black hole interior “space-and-time-reversal”. Specifically, it is proposed that the “singularity” space of the black hole interior is time-like and the expansion time of the black hole interior is space-like. The resemblance of this new insider interpretation to our own expanding and redshifting big bang universe is compelling. 展开更多
关键词 black Holes Complementarity Cosmological Models Rh = ct Models Flat Space Cosmology Schwarzschild Cosmology Thought experiment Dark Energy Quantum Vacuum
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