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How to use the Surveillance,Epidemiology,and End Results(SEER)data:research design and methodology
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作者 Wen-Qiang Che Yuan-Jie Li +5 位作者 Chi-Kwan Tsang Yu-Jiao Wang Zheng Chen Xiang-Yu Wang An-Ding Xu Jun Lyu 《Military Medical Research》 SCIE CAS CSCD 2024年第5期686-696,共11页
In the United States(US),the Surveillance,Epidemiology,and End Results(SEER)program is the only comprehensive source of population-based information that includes stage of cancer at the time of diagnosis and patient s... In the United States(US),the Surveillance,Epidemiology,and End Results(SEER)program is the only comprehensive source of population-based information that includes stage of cancer at the time of diagnosis and patient survival data.This program aims to provide a database about cancer incidence and survival for studies of surveillance and the development of analytical and methodological tools in the cancer field.Currently,the SEER program covers approximately half of the total cancer patients in the US.A growing number of clinical studies have applied the SEER database in various aspects.However,the intrinsic features of the SEER database,such as the huge data volume and complexity of data types,have hindered its application.In this review,we provided a systematic overview of the commonly used methodologies and study designs for retrospective epidemiological research in order to illustrate the application of the SEER database.Therefore,the goal of this review is to assist researchers in the selection of appropriate methods and study designs for enhancing the robustness and reliability of clinical studies by mining the SEER database. 展开更多
关键词 Surveillance Epidemiology and End results(SEER) Big data EPIDEMIOLOGY methodologIES Study design
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Optimizing Bucket Elevator Performance through a Blend of Discrete Element Method, Response Surface Methodology, and Firefly Algorithm Approaches
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作者 Pirapat Arunyanart Nithitorn Kongkaew Supattarachai Sudsawat 《Computers, Materials & Continua》 SCIE EI 2024年第8期3379-3403,共25页
This research introduces a novel approach to enhancing bucket elevator design and operation through the integration of discrete element method(DEM)simulation,design of experiments(DOE),and metaheuristic optimization a... This research introduces a novel approach to enhancing bucket elevator design and operation through the integration of discrete element method(DEM)simulation,design of experiments(DOE),and metaheuristic optimization algorithms.Specifically,the study employs the firefly algorithm(FA),a metaheuristic optimization technique,to optimize bucket elevator parameters for maximizing transport mass and mass flow rate discharge of granular materials under specified working conditions.The experimental methodology involves several key steps:screening experiments to identify significant factors affecting bucket elevator operation,central composite design(CCD)experiments to further explore these factors,and response surface methodology(RSM)to create predictive models for transport mass and mass flow rate discharge.The FA algorithm is then applied to optimize these models,and the results are validated through simulation and empirical experiments.The study validates the optimized parameters through simulation and empirical experiments,comparing results with DEM simulation.The outcomes demonstrate the effectiveness of the FA algorithm in identifying optimal bucket parameters,showcasing less than 10%and 15%deviation for transport mass and mass flow rate discharge,respectively,between predicted and actual values.Overall,this research provides insights into the critical factors influencing bucket elevator operation and offers a systematic methodology for optimizing bucket parameters,contributing to more efficient material handling in various industrial applications. 展开更多
关键词 Discrete element method(DEM) design of experiments(DOE) firefly algorithm(FA) response surface methodology(RSM)
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Optimization and Characterization of Cellulose Extraction from Grevillea robusta (Silky Oak) Leaves by Soda-Anthraquinone Pulping Using Response Surface Methodology
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作者 Catherine N. Muya John M. Onyari +2 位作者 Lydia W. Njenga Joab O. Onyango Wilson M. Gitari 《Green and Sustainable Chemistry》 2024年第3期43-65,共23页
Response surface methodology (RSM) using the central composite design (CCD) was applied to examine the impact of soda-anthraquinone pulping conditions on Grevillea robusta fall leaves. The pulping factors studied were... Response surface methodology (RSM) using the central composite design (CCD) was applied to examine the impact of soda-anthraquinone pulping conditions on Grevillea robusta fall leaves. The pulping factors studied were: NaOH charge 5% to 20% w/v, pulping time 30 to 180 minutes, and the anthraquinone charge 0.1 to 0.5% w/w based on the oven-dried leaves. The responses evaluated were the pulp yield, cellulose content, and the degree of delignification. Various regression models were used to evaluate the effects of varying the pulping conditions. The optimum conditions attained were;NaOH charge of 14.63%, 0.1% anthraquinone, and a pulping period of 154 minutes, corresponding to 20.68% pulp yield, 80.56% cellulose content, and 70.34% lignin removal. Analysis of variance (ANOVA), was used to determine the most important variables that improve the extraction process of cellulose. The experiment outcomes matched those predicted by the model (Predicted R2 = 0.9980, Adjusted R2 = 0.9994), demonstrating the adequacy of the model used. FTIR analysis confirmed the elimination of the non-cellulosic fiber constituents. The lignin and hemicellulose-related bands (around 1514 cm−1, 1604 cm−1, 1239 cm−1, and 1734 cm−1) decreased with chemical treatment, indicating effective cellulose extraction by the soda-anthraquinone method. Similar results were obtained by XRD, SEM and thermogravimetric analysis of the extracted cellulose. Therefore, Grevillea robusta fall leaves are suitable renewable, cost-effective, and environmentally friendly non-wood biomass for cellulose extraction. 展开更多
关键词 Cellulose Extraction Response Surface methodology Central Composite design DELIGNIFICATION
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Optimization for Microbial Degumming of Ramie with Bacillus subtilis DZ_(5) in Submerged Fermentation by Orthogonal Array Design and Response Surface Methodology 被引量:1
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作者 刘芬 陈杨栋 +2 位作者 朱鹏 曹张军 张兴群 《Journal of Donghua University(English Edition)》 CAS 2023年第5期475-481,共7页
As a kind of natural fiber,ramie fiber has distinctive advantages in textile application,but the application is limited due to the traditional degumming mode.Compared with the traditional degumming process,the microbi... As a kind of natural fiber,ramie fiber has distinctive advantages in textile application,but the application is limited due to the traditional degumming mode.Compared with the traditional degumming process,the microbial degumming process has many advantages.To obtain the optimal conditions for degumming ramie with Bacillus subtilis DZ_(5)(BS DZ_(5)),a combined statistical approach of orthogonal array design(OAD)and response surface methodology(RSM)was used.The influences of initial pH of the bacteria medium,culture temperature,shaking speed,degumming time and inoculum size on submerged fermentation degumming were evaluated by using fractional factorial design.The main factors in the analysis were culture temperature,shaking speed and initial pH.The residual gum mass fraction was used as the optimization index,and the optimal conditions for degumming were determined by central composite design and RSM.Thus with only a limited number of experiments,an optimal ramie microbial degumming condition was found as the culture temperature of 40℃,the initial pH in the culture medium of 8.5,the shaking speed of 205 r/min,the degumming time of 96 h and the inoculum size of 5%.After microbial degumming of ramie under the optimal conditions,there was only 10.6%residual gum by mass in the fiber.In addition,the effective degumming of BS DZ_(5)was also confirmed by a scanning electron microscope(SEM). 展开更多
关键词 microbial degumming OPTIMIZATION RAMIE orthogonal array design(OAD) response surface methodology(RSM)
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Device Robust-Design by Using Response Surface Methodology
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作者 谢晓锋 鲁勇 +1 位作者 张文俊 杨之廉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第8期817-824,共8页
Device robust-design is inherently a multiple-objective optimization problem.Using design of experiments (DoE) combined with response surface methodology (RSM) can satisfy the great incentive to reduce the number of t... Device robust-design is inherently a multiple-objective optimization problem.Using design of experiments (DoE) combined with response surface methodology (RSM) can satisfy the great incentive to reduce the number of technology CAD(TCAD) simulations that need to be performed.However,the errors of RSM models might be large enough to diminish the validity of the results for some nonlinear problems.To find the feasible design space,a new method with objectives-oriented design in generations that takes the errors of RSM model into account is presented.After the augment design of experiments in promising space according to the results of RSM model in current generation,the feasible space will be emerging as the model errors deceasing.The results on FIBMOS examples show that the methodology is efficient. 展开更多
关键词 response surface methodology design of experiments device robust-design
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Reversing design methodology of investment casting die profile based on ProCAST 被引量:11
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作者 Dou Yangqing Bu Kun +1 位作者 Dou Yangliu Dong Yiwei 《China Foundry》 SCIE CAS 2010年第2期132-137,共6页
Turbine blade is one of the critical components of aircraft engine.The performance of the engine depends on the shape and dimensions of components,but superalloy blade material cannot be easily machined.Although inves... Turbine blade is one of the critical components of aircraft engine.The performance of the engine depends on the shape and dimensions of components,but superalloy blade material cannot be easily machined.Although investment casting is an ideal process for such net-shape components,it requires an accurate determination of the casting-die profile.In this paper,a reversing design methodology for investment casting die using ProCAST is proposed.By combining the methods of simplifying grid files and quick sorting,the efficiency of sorting and matching can be largely improved.Further,the mould/die cavity anti-deformation system can be easily built.With ProCAST,the optimized die profile for investment casting can be established. 展开更多
关键词 investment casting reversing design methodology node matching numerical simulation PROCAST
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Formulation optimization of scutellarin-loaded HP-β-CD/chitosan nanoparticles using response surface methodology with Box–Behnken design 被引量:4
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作者 Shanshan Liu Paul C.Ho 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2017年第4期378-385,共8页
The aim of this paper is to investigate and optimize the preparation of scutellarin(SCU)-loaded HP-β-CD/chitosan(CS) nanoparticles(CD/CS-SCU-NPs). CD/CS-SCU-NPs were prepared by ionic cross-linking method and the pro... The aim of this paper is to investigate and optimize the preparation of scutellarin(SCU)-loaded HP-β-CD/chitosan(CS) nanoparticles(CD/CS-SCU-NPs). CD/CS-SCU-NPs were prepared by ionic cross-linking method and the process and formulation variables were optimized using response surface methodology(RSM) with a three-level, three factor Box–Behnken design(BBD).The independent variables were the added amounts of CS, sodium tripolyphosphate(TPP)and Pluronic F-68 during the preparation. Dependent variables(responses) were particle size and entrapment efficiency. Mathematical equations and respond surface plots were used to correlate independent and dependent variables.The preparation process and formulation variables were optimized to achieve minimum particle size and maximum entrapment efficiency by calculating the overall desirability value(OD). The optimized NP formulation was characterized for particle size, PDI, zeta potential, entrapment efficiency and in vitro drug release.According to the results, an optimized CD/CS-SCU-NP formulation was prepared. Results for particle size, PDI, zeta potential and entrapment efficiency were found to be around 200 nm,0.5, 25 mV, and 70% respectively. For in vitro study, the release of SCU from the NPs exhibited a biphasic release and was in accordance with Higuchi equation. The optimized preparation was simple with the probability for industrialization. The combination use of RSM, BBD and overall desirability values could provide a promising application for incorporating CD into CS nanoparticles as drug delivery carrier and help develop lab-scale procedures. 展开更多
关键词 SCUTELLARIN Response surface methodology Box–Behnken design CHITOSAN HP-β-CD Nanoparticles
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Optimal design of butterfly-shaped linear ultrasonic motor using finite element method and response surface methodology 被引量:9
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作者 时运来 陈超 赵淳生 《Journal of Central South University》 SCIE EI CAS 2013年第2期393-404,共12页
A new method for optimizing a butterfly-shaped linear ultrasonic motor was proposed to maximize its mechanical output. The finite element analysis technology and response surface methodology were combined together to ... A new method for optimizing a butterfly-shaped linear ultrasonic motor was proposed to maximize its mechanical output. The finite element analysis technology and response surface methodology were combined together to realize the optimal design of the butterfly-shaped linear ultrasonic motor. First, the operation principle of the motor was introduced. Second, the finite element parameterized model of the stator of the motor was built using ANSYS parametric design language and some structure parameters of the stator were selected as design variables. Third, the sample points were selected in design variable space using latin hypercube Design. Through modal analysis and harmonic response analysis of the stator based on these sample points, the target responses were obtained. These sample points and response values were combined together to build a response surface model. Finally, the simplex method was used to find the optimal solution. The experimental results showed that many aspects of the design requirements of the butterfly-shaped linear ultrasonic motor have been fulfilled. The prototype motor fabricated based on the optimal design result exhibited considerably high dynamic performance, such as no-load speed of 873 ram/s, maximal thrust of 27.5 N, maximal efficiency of 43%, and thrust-weight ratio of 45.8. 展开更多
关键词 linear ultrasonic motor PIEZOELECTRIC optimal design response surface methodology finite element method
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Application of response surface methodology and central composite rotatable design for modeling the influence of some operating variables of the lab scale thickener performance 被引量:2
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作者 Aghajani Shahrivar Alireza Soltani Goharrizi Ataallah +3 位作者 Ebrahimzadeh Gheshlaghi Majid Sarafi Amir Razmirad Mohammad Abdollahi Hadi 《International Journal of Mining Science and Technology》 SCIE EI 2013年第5期717-724,共8页
This study discussed the application of response surface methodology(RSM)and central composite rotatable design(CCRD)for modeling and optimization of the influence of some operating variables on the performance of a l... This study discussed the application of response surface methodology(RSM)and central composite rotatable design(CCRD)for modeling and optimization of the influence of some operating variables on the performance of a lab scale thickener for dewatering of tailing in the flotation circuit.Four thickener operating variables,namely feed flowrate,solid percent,flocculant dosage and feedwell height were changed during the tests based on CCRD.The ranges of values of the thickener variables used in the design were a feed flowrate of 9–21 L/min,solid percent of 8%–20%,flocculant dosage of 1.25–4.25 g/t and feedwell height of 16–26 cm.A total of 30 thickening tests were conducted using lab scale thickener on flotation tailing obtained from the Sarcheshmeh copper mine,Iran.The underflow solid percent and bed height were expressed as functions of four operating parameters of thickener.Predicted values were found to be in good agreement with experimental values(R2values of 0.992 and 0.997 for underflow solid percent and bed height,respectively).This study has shown that the RSM and CCRD could effciently be applied for the modeling of thickener for dewatering of flotation tailing. 展开更多
关键词 Response surface methodology Central composite rotatable design MODELING THICKENER
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Response Surface Methodology-Based SERS for Determination of Gymnodimine
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作者 Siyang Chan Yaoyi Wu +2 位作者 Yifan Liu Donghang Yin Fei Wang 《American Journal of Analytical Chemistry》 2023年第8期305-325,共21页
Gymnodimine (GYM), a fast-acting marine toxin, is destructive to aquaculture and human health through contaminated shellfish. The current detection methods in GYM have definite drawbacks in operation, such as the dema... Gymnodimine (GYM), a fast-acting marine toxin, is destructive to aquaculture and human health through contaminated shellfish. The current detection methods in GYM have definite drawbacks in operation, such as the demand for delicate instruments and the consumption of time. Therefore, silver colloid was utilized as a surface-enhanced Raman scattering (SERS) desirable substrate for sensitive and rapid detection of GYM in lake and shellfish samples. The theoretical spectrum of GYM is calculated by density functional theory (DFT), and the substrate performance is evaluated by a rhodamine 6 G probe. Under the optimal SERS experimental condition calculated by the response surface methodology, the low limit of detection of 0.105 μM with R<sup>2</sup> of 0.9873 and a broad linearity range of 0.1 - 10 μM was achieved for GYM detection. In addition, the substrate was satisfyingly applied to detect gymnodimine in the lake and shellfish matrix samples with LOD as low as 0.148 μM and 0.170 μM, respectively. These results demonstrated a promising SERS platform for detecting marine toxins in seafood for food safety and pharmaceutical research. 展开更多
关键词 Surface-Enhanced Raman Scattering Gymnodimine Ag Colloid Box-Behnken design Response Surface methodology
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A Mooring System Deployment Design Methodology for Vessels at Varying Water Depths 被引量:2
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作者 XU Sheng-wen LIANG Ming-xiao +1 位作者 WANG Xue-feng DING Ai-bing 《China Ocean Engineering》 SCIE EI CSCD 2020年第2期185-197,共13页
In this paper,a methodology for designing mooring system deployment for vessels at varying water depths is proposed.The Non-dominated Sorting Genetic Algorithm-II(NSGA-II)is combined with a self-dependently developed ... In this paper,a methodology for designing mooring system deployment for vessels at varying water depths is proposed.The Non-dominated Sorting Genetic Algorithm-II(NSGA-II)is combined with a self-dependently developed vessel-mooring coupled program to find the optimal mooring system deployment considering both station-keeping requirements and the safety of the mooring system.Two case studies are presented to demonstrate the methodology by designing the mooring system deployments for a very large floating structure(VLFS)module and a semi-submersible platform respectively at three different water depths.It can be concluded from the obtained results that the mooring system can achieve a better station-keeping ability with relatively shorter mooring line when deployed in the shallow water.The safety factor of mooring line is mainly dominated by the maximum instantaneous tension increment in the shallow water,while the pre-tension has a decisive influence on the safety factor of the mooring line in the deep water. 展开更多
关键词 mooring system deployment design methodology NSGA-II varying water depths
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An Innovative Soft Design Science Methodology for Improving Development of a Secure Information System in Tanzania Using Multi-Layered Approach 被引量:2
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作者 Maduhu Mshangi Edephonce Ngemera Nfuka Camilius Sanga 《Journal of Information Security》 2017年第3期141-165,共25页
This paper presents an innovative Soft Design Science Methodology for improving information systems security using multi-layered security approach. The study applied Soft Design Science Methodology to address the prob... This paper presents an innovative Soft Design Science Methodology for improving information systems security using multi-layered security approach. The study applied Soft Design Science Methodology to address the problematic situation on how information systems security can be improved. In addition, Soft Design Science Methodology was compounded with mixed research methodology. This holistic approach helped for research methodology triangulation. The study assessed security requirements and developed a framework for improving information systems security. The study carried out maturity level assessment to determine security status quo in the education sector in Tanzania. The study identified security requirements gap (IT security controls, IT security measures) using ISO/IEC 21827: Systems Security Engineering-Capability Maturity Model (SSE-CMM) with a rating scale of 0 - 5. The results of this study show that maturity level across security domain is 0.44 out of 5. The finding shows that the implementation of IT security controls and security measures for ensuring security goals are lacking or conducted in ad-hoc. Thus, for improving the security of information systems, organisations should implement security controls and security measures in each security domain (multi-layer security). This research provides a framework for enhancing information systems security during capturing, processing, storage and transmission of information. This research has several practical contributions. Firstly, it contributes to the body of knowledge of information systems security by providing a set of security requirements for ensuring information systems security. Secondly, it contributes empirical evidence on how information systems security can be improved. Thirdly, it contributes on the applicability of Soft Design Science Methodology on addressing the problematic situation in information systems security. The research findings can be used by decision makers and lawmakers to improve existing cyber security laws, and enact laws for data privacy and sharing of open data. 展开更多
关键词 SOFT design SCIENCE Information SYSTEMS Security design SCIENCE Research SOFT SYSTEMS methodology Multi-Layered APPROACH
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Response surface methodology-based hybrid robust design optimization for complex product under mixed uncertainties 被引量:1
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作者 WAN Liangqi CHEN Hongzhuan OUYANG Linhan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第2期308-318,共11页
Minimizing the impact of the mixed uncertainties(i.e.,the aleatory uncertainty and the epistemic uncertainty) for a complex product of compliant mechanism(CPCM) quality improvement signifies a fascinating research top... Minimizing the impact of the mixed uncertainties(i.e.,the aleatory uncertainty and the epistemic uncertainty) for a complex product of compliant mechanism(CPCM) quality improvement signifies a fascinating research topic to enhance the robustness.However, most of the existing works in the CPCM robust design optimization neglect the mixed uncertainties, which might result in an unstable design or even an infeasible design. To solve this issue, a response surface methodology-based hybrid robust design optimization(RSM-based HRDO) approach is proposed to improve the robustness of the quality characteristic for the CPCM via considering the mixed uncertainties in the robust design optimization. A bridge-type amplification mechanism is used to manifest the effectiveness of the proposed approach. The comparison results prove that the proposed approach can not only keep its superiority in the robustness, but also provide a robust scheme for optimizing the design parameters. 展开更多
关键词 response surface methodology (RSM) HYBRID robust design optimization (HRDO) uncertainty complex product of compliant mechanism (CPCM)
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Engineering Design Optimization Based on Intelligent Response Surface Methodology 被引量:1
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作者 宋国辉 吴瑜 李从心 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第3期285-290,共6页
An intelligent response surface methodology (IRSM) was proposed to achieve the most competitive metal forming products, in which artificial intelligence technologies are introduced into the optimization process. It is... An intelligent response surface methodology (IRSM) was proposed to achieve the most competitive metal forming products, in which artificial intelligence technologies are introduced into the optimization process. It is used as simple and inexpensive replacement for computationally expensive simulation model. In IRSM, the optimal design space can be reduced greatly without any prior information about function distribution. Also, by identifying the approximation error region, new design points can be supplemented correspondingly to improve the response surface model effectively. The procedure is iterated until the accuracy reaches the desired threshold value. Thus, the global optimization can be performed based on this substitute model. Finally, we present an optimization design example about roll forming of a "U" channel product. 展开更多
关键词 design optimization intelligent response surface methodology roll forming rough set
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Synoptic review on existing and potential sources for bias in dental research methodology with methods on their prevention and remedies
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作者 Amit Arvind Agrawal Nilima Prakash +3 位作者 Mohammad Almagbol Mohammed Alobaid Abdullah Alqarni Hammam Altamni 《World Journal of Methodology》 2023年第5期426-438,共13页
The results of years of dental study serve as the foundation for the practise of medicine and,for that matter,dentistry.Doctors may have their own preferences for techniques and materials,but whether directly or indir... The results of years of dental study serve as the foundation for the practise of medicine and,for that matter,dentistry.Doctors may have their own preferences for techniques and materials,but whether directly or indirectly,their decisions are influenced by systematic reviews and meta-analyses.However,due to poorly conducted or presented research,this very basic foundation may not be reliable.Bias in research is one of several factors that might make study results or research itself unreliable.Bias can be introduced into research at many stages,deliberately or unknowingly.Bias can appear at any point during the research process,even before the study itself begins.There are many biases in research,but some of them are more relevant to dentistry research than others.Because it is said that“eyes see what the mind knows”,it is essential to have a complete understanding of the different types of bias,how and when they get entrenched,and what steps may be taken to prevent or lessen them if they do occur.This comprehensive summary of bias in dentistry research is provided by this synoptic review.The goal is to identify gaps and measures that have been taken-or that should have been taken-by providing both descriptive and evaluative summaries,as well as examples from the literature,when needed. 展开更多
关键词 Dental research Bias(epidemiology) Research methodology Research design Epidemiologic methods
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BIM Methodology Applied in Structural Design: Analysis of Interoperability in ArchiCAD/ETABS Process 被引量:1
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作者 Alcínia Zita Sampaio Augusto M. Gomes Tomas Farinha 《Journal of Software Engineering and Applications》 2021年第6期189-206,共18页
<span style="font-family:Verdana;">The Building Information Modeling (BIM) methodology considers the representation of the building as a virtual BIM model and its main concept is to centralize all the ... <span style="font-family:Verdana;">The Building Information Modeling (BIM) methodology considers the representation of the building as a virtual BIM model and its main concept is to centralize all the information generated throughout the development of the project. Structural design involves a set of tasks, namely, structure definition, structural analyses, and after the generation of drawings and technical documentation. In all processes, it is required confidence in data transferred between the BIM systems used, and to support this, a high level of interoperability is claimed. The present study aims to evaluate the degree of interoperability between the BIM-based platforms, ArchiCAD (Graphisoft), Revit (Autodesk), and ETABS (CSI). Two-way data flows between these systems were explored using distinct transfer strategies: add-in applications;Industry Foundation Classes (IFC) standard data format. The research made allows identifying the most appropriate procedure to be adopted by structural engineers, given the interoperability limitations verified, enabling the establishment of a practical guide of sequential procedures on the development of structural designs using BIM tools.</span> 展开更多
关键词 Structural design BIM methodology INTEROPERABILITY BIM Tools
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Catalytic Hydrothermal Liquefaction of Water Hyacinth Using Fe3O4/NiO Nanocomposite: Optimization of Reaction Conditions by Response Surface Methodology
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作者 Godwin Aturagaba Dan Egesa +1 位作者 Edward Mubiru Emmanuel Tebandeke 《Journal of Sustainable Bioenergy Systems》 2023年第3期73-98,共26页
This research aimed at optimizing the reaction conditions for the catalytic hydrothermal liquefaction (HTL) of water hyacinth using iron oxide/nickel oxide nanocomposite as catalysts. The iron oxide/nickel oxide nanoc... This research aimed at optimizing the reaction conditions for the catalytic hydrothermal liquefaction (HTL) of water hyacinth using iron oxide/nickel oxide nanocomposite as catalysts. The iron oxide/nickel oxide nanocomposite was synthesized by the co-precipitation method and used in the hydrothermal liquefaction of water hyacinth. The composition and structural morphology of the synthesized catalysts were determined using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic absorption spectroscopy (AAS). The particle size distribution of the catalyst nanoparticles was determined by the Image J software. Three reaction parameters were optimized using the response surface methodology (RSM). These were: temperature, residence time, and catalyst dosage. A maximum bio-oil yield of 59.4 wt% was obtained using iron oxide/nickel oxide nanocomposite compared to 50.7 wt% obtained in absence of the catalyst. The maximum bio-oil yield was obtained at a temperature of 320°C, 1.5 g of catalyst dosage, and 60 min of residence time. The composition of bio-oil was analyzed using gas chromatography-mass spectroscopy (GC-MS) and elemental analysis. The GC-MS results showed an increase of hydrocarbons from 58.3% for uncatalyzed hydrothermal liquefaction to 88.66% using iron oxide/nickel oxide nanocomposite. Elemental analysis results revealed an increase in the hydrogen and carbon content and a reduction in the Nitrogen, Oxygen, and Sulphur content of the bio-oil during catalytic HTL compared to HTL in absence of catalyst nanoparticles. The high heating value increased from 33.5 MJ/Kg for uncatalyzed hydrothermal liquefaction to 38.6 MJ/Kg during the catalytic HTL. The catalyst nanoparticles were recovered from the solid residue by sonication and magnetic separation and recycled. The recycled catalyst nanoparticles were still efficient as hydrothermal liquefaction (HTL) catalysts and were recycled four times. The application of iron oxide/ nickel oxide nanocomposites in the HTL of water hyacinth increases the yield of bio-oil and improves its quality by reducing hetero atoms thus increasing its energy performance as fuel. Iron oxide/nickel oxide nanocomposites used in this study are widely available and can be easily recovered magnetically and recycled. This will potentially lead to an economical, environmentally friendly, and sustainable way of converting biomass into biofuel. 展开更多
关键词 Catalytic Hydrothermal Liquefaction Water Hyacinth BIO-OIL Central Com-posite design Response Surface methodology OPTIMIZATION
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Methodology for Design of Reactive Distillation Column and Kinetics for Isoamylene Etherification Catalysed by Amberlyst 35 被引量:1
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作者 Wu Yanli Li Wenying +1 位作者 Li Qiang Feng Jie 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2016年第4期128-136,共9页
Isoamylene from the Fischer-Tropsch syncrude can be transformed to valuable fuel oxygenate additives through an equilibrium limited etherification reaction with methanol. A reactive distillation process is established... Isoamylene from the Fischer-Tropsch syncrude can be transformed to valuable fuel oxygenate additives through an equilibrium limited etherification reaction with methanol. A reactive distillation process is established to increase isoamylene conversion. Facing the challenge of improving product purity at the same time, an equilibrium stage model based design methodology is proposed and illustrated step-by-step for converting the Fischer-Tropsch C_5 olefins to tert-amyl methyl ether(TAME) process by using Aspen Plus. Under the guide of the proposed methodology, the design leads to a TAME product purity of higher than 95% and an isoamylene conversion of higher than 90%. The etherification kinetics over Amberlyst 35 is also studied within a temperature range of 60 ℃ to 75 ℃ to shed more light on the feasibility of process development. The methodology provides an effective reactive distillation column design to achieve the target reactant conversion and product purity simultaneously. 展开更多
关键词 Amberlyst 35 design methodology etherification isoamylene reactive distillation column
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Adsorption of Malachite Green Using Activated Carbon from Mangosteen Peel: Optimization Using Box-Behnken Design
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作者 Nabila Eka Yuningsih Latifa Ariani +4 位作者 Suprapto Suprapto Ita Ulfin Harmami Harmami Hendro Juwono Yatim Lailun Ni’mah 《Journal of Renewable Materials》 EI CAS 2024年第5期981-992,共12页
In this research,activated carbon from mangosteen peel has been synthesized using sulfuric acid as an activator.The adsorption performance of the activated carbon was optimized using malachite green dye as absorbate.M... In this research,activated carbon from mangosteen peel has been synthesized using sulfuric acid as an activator.The adsorption performance of the activated carbon was optimized using malachite green dye as absorbate.Mala-chite green dye waste is a toxic and non-biodegradable material that damages the environment.Optimization of adsorption processes was carried out using Response Surface Methodology(RSM)with a Box-Behnken Design(BBD).The synthesized activated carbon was characterized using FTIR and SEM instruments.The FTIR spectra confirmed the presence of a sulfonate group(-SO_(3)H)in the activated carbon,indicating that the activation pro-cess using sulfuric acid was successful.SEM characterization shows that activated carbon has porous morphology.Optimization was carried out for three adsorption parameters,namely contact time(20,60,and 120 min),adsor-bent mass(0.005,0.025,and 0.05 g),and initial concentration of malachite green solution(5,50,and 100 mg·L^(-1)).The concentration of the malachite green solution was determined using a UV-Vis spectrophotometer at the max-imum wavelength of malachite green,618 nm.The optimum of malachite green adsorption using mangosteen peel activated carbon was obtained at a contact time of 80 min,an adsorbent mass of 0.032 g,and malachite green initial concentration of 25 mg·L^(-1),with a maximum removal percentage and maximum adsorption capacity of 93.66%and 19.345 mg·g^(-1),respectively. 展开更多
关键词 Response surface methodology DYES activated carbon experimental design
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“BOTTOM-UP”OR“TOP-DOWN”——ON THE METHODOLOGY OF URBAN DESIGN
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作者 王建国 《Journal of Southeast University(English Edition)》 EI CAS 1992年第1期53-60,共8页
Aiming at the problems cased by the fast increase of industry and popula-tion in China,the paper cxpounds the conceptual connotation of urban dcsign and theinteraction between urban form and design,sums up the“top-d... Aiming at the problems cased by the fast increase of industry and popula-tion in China,the paper cxpounds the conceptual connotation of urban dcsign and theinteraction between urban form and design,sums up the“top-down”and“bottom-up”urban design approaches in history,and points out that subject of urban design——as anavailable approach to cope with the problems of building cities——should be put forwardin China as quickly as possible. 展开更多
关键词 URBAN design methodology VALUE system design proeess
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