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Euler’s First-Order Explicit Method–Peridynamic Differential Operator for Solving Population Balance Equations of the Crystallization Process
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作者 Chunlei Ruan Cengceng Dong +2 位作者 Kunfeng Liang Zhijun Liu Xinru Bao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期3033-3049,共17页
Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridyna... Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed. 展开更多
关键词 Population balance equation CRYsTALLIZATION peridynamic differential operator Euler’s first-order explicit method
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Inverse Differential Operators in Time and Space
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作者 Edwin Eugene Klingman 《Journal of Applied Mathematics and Physics》 2023年第12期3789-3799,共11页
When one function is defined as a differential operation on another function, it’s often desirable to invert the definition, to effectively “undo” the differentiation. A Green’s function approach is often used to ... When one function is defined as a differential operation on another function, it’s often desirable to invert the definition, to effectively “undo” the differentiation. A Green’s function approach is often used to accomplish this, but variations on this theme exist, and we examine a few such variations. The mathematical analysis of  is sought in the form  if such an inverse operator exists, but physics is defined by both mathematical formula and ontological formalism, as I show for an example based on the Dirac equation. Finally, I contrast these “standard” approaches with a novel exact inverse operator for field equations. 展开更多
关键词 Matrix-Inverse Differential operators Green’s Functions Dirac’s Equation Wave Equations Inverse Curl operator
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CARLESON MEASURES,RIEMANN-STIELTJES OPERATORS AND MULTIPLIERS ON F(p,q,s)SPACES IN THE UNIT BALL OF C^n 被引量:3
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作者 彭茹 吴悠 邓方文 《Acta Mathematica Scientia》 SCIE CSCD 2016年第3期635-654,共20页
This paper is devoted to characterizing the Riemann-Stieltjes operators and pointwise multipliers on F(p, q, s) spaces in the unit ball of C^n which contain many classical function spaces, such as the Bloch space, B... This paper is devoted to characterizing the Riemann-Stieltjes operators and pointwise multipliers on F(p, q, s) spaces in the unit ball of C^n which contain many classical function spaces, such as the Bloch space, BMOA and Q8 spaces. The boundedness and compactness of these operators on F(p, q, s) spaces are characterized by means of an embedding theorem, i.e., F(p,q, s) spaces boundedly embedded into the tent-type spaces Tp,s^∞(μ) 展开更多
关键词 Carleson measures F(p q s spaces tent-type spaces Riemann-stieltjes operators MULTIPLIERs
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Weighted composition operators from F(p,q,s) spaces to Bers-type spaces in the unit ball 被引量:2
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作者 LU Xiao-fen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第4期462-472,共11页
This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to ... This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to Bers-type spaces Hv^∞( or little Bers-type spaces Hv,o∞ ), where v is normal. 展开更多
关键词 F(p Q s space Bers-type space weighted composition operator unit ball
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WEYL'S TYPE THEOREMS AND HYPERCYCLIC OPERATORS 被引量:3
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作者 M.H.M.Rashid 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期539-551,共13页
For a bounded operator T acting on an infinite dimensional separable Hilbert space H, we prove the following assertions: (i) If T or T* ∈ SC, then generalized a- Browder's theorem holds for f(T) for every f ∈... For a bounded operator T acting on an infinite dimensional separable Hilbert space H, we prove the following assertions: (i) If T or T* ∈ SC, then generalized a- Browder's theorem holds for f(T) for every f ∈ Hol(σ(T)). (ii) If T or T* ∈ HC has topological uniform descent at all λ ∈ iso(a(T)), then generalized Weyl's theorem holds for f(T) for every f ∈ Hol(σ(T)). (iii) If T ∈ HC has topological uniform descent at all λ ∈(T), then T satisfies generalized Weyl's theorem. (iv) Let T ∈ HC. If T satisfies the growth condition Gd(d 〉 1), then generalized Weyl's theorem holds for f(T) for every f ∈ Hol(σ(T)). (v) If T ∈ SC, then, f(OssF+ (T)) = aSBF+ (f(T)) for all f ∈ Hol(σ(T)). (vi) Let T be a-isoloid such that T* ∈ HC. If T - AI has finite ascent at every A ∈ Eσ(T) and if F is of finite rank on Hsuch that TF = FT, then T ∈ F obeys generalized a-Weyl's theorem. 展开更多
关键词 Weyl's theorem hypercyclic operators supercyclic operators
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NEW WEIGHTED MULTILINEAR OPERATORS AND COMMUTATORS OF HARDY-CESàRO TYPE 被引量:2
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作者 Ha Duy HUNG Luong Dang KY 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1411-1425,共15页
This paper deals with a general class of weighted multilinear Hardy-Cesaro op- erators that acts on the product of Lebesgue spaces and central Morrey spaces. Their sharp bounds are also obtained. In addition, we obtai... This paper deals with a general class of weighted multilinear Hardy-Cesaro op- erators that acts on the product of Lebesgue spaces and central Morrey spaces. Their sharp bounds are also obtained. In addition, we obtain sufficient and necessary conditions on weight functions so that the commutators of these weighted multilinear Hardy-Cesaro oper- ators (with symbols in central BMO spaces) are bounded on the product of central Morrey spaces. These results extends known results on multilinear Hardy operators. 展开更多
关键词 Hardy-Ces^ro operators Hardy's inequality multilinear Hardy operator weig-hted Hardy-Littlewood averages
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LOWER BOUNDS OF DIRICHLET EIGENVALUES FOR A CLASS OF FINITELY DEGENERATE GRUSHIN TYPE ELLIPTIC OPERATORS 被引量:2
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作者 陈化 陈洪葛 +1 位作者 段忆芮 胡鑫 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1653-1664,共12页
Let Ω be a bounded open domain in Rn with smooth boundary Ω, X =(X1,X2,... ,Xm) be a system of real smooth vector fields defined on Ω and the bound-ary Ω is non-characteristic for X. If X satisfies the HSrmande... Let Ω be a bounded open domain in Rn with smooth boundary Ω, X =(X1,X2,... ,Xm) be a system of real smooth vector fields defined on Ω and the bound-ary Ω is non-characteristic for X. If X satisfies the HSrmander's condition, then the vectorfield is finitely degenerate and the sum of square operator △X =m∑j=1 X2 j is a finitely de-generate elliptic operator. In this paper, we shall study the sharp estimate of the Dirichlet eigenvalue for a class of general Grushin type degenerate elliptic operators △x on Ω. 展开更多
关键词 Dirichlet eigenvalues finitely degenerate elliptic operators Hsrmander's con-dition sub-elliptic estimate Grushin type operator
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Recording the direct surgeon’s view with an operating microscopic view improves microscopic ophthalmic surgery training
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作者 Masayuki Akimoto Kosei Tomita +1 位作者 Miyo Yoshida Yuki Hama 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第9期1555-1558,共4页
AIM:To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope,which lacks information on the movement and position of the surgeon’s hands,and to fac... AIM:To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope,which lacks information on the movement and position of the surgeon’s hands,and to facilitate the reproduction of a skilled surgeon’s technique by a surgeon in training.METHODS:A small camera was attached to the operating microscope with a custom adapter.Microscopic surgeon’s view and direct surgeon’s view through this new camera were recorded in the surgical recording system.Both movies were synchronized and analyzed how do surgeons handle the instruments.RESULTS:A small camera attached to the operating microscope allowed the surgeon’s hands motion to be recorded without interfering with the surgeon’s movements.Different surgeons used different methods to manipulate the ultrasound handpiece and the irrigation/aspiration device.Even in the simple paracentesis procedure,different surgeons used different methods.Surgeons-in-training were able to identify and improve their weaknesses by watching synchronized movies of their hand motions and microscopic view.CONCLUSION:Simultaneous recording the surgical field out of the operating microscopic view by a small camera set on the microscope is comprehensive and improves surgeons-in-training understanding and learning surgeries. 展开更多
关键词 operating microscopic view direct surgeon’s view video recording microscopic surgery training
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Exact Inverse Operator on Field Equations 被引量:2
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作者 Edwin Eugene Klingman 《Journal of Applied Mathematics and Physics》 2020年第10期2213-2222,共10页
Differential equations of electromagnetic and similar physical fields are generally solved via antiderivative Green’s functions involving integration over a region and its boundary. Research on the Kasner metric reve... Differential equations of electromagnetic and similar physical fields are generally solved via antiderivative Green’s functions involving integration over a region and its boundary. Research on the Kasner metric reveals a variable boundary deemed inappropriate for standard anti-derivatives, suggesting the need for an alternative solution technique. In this work I derive such a solution and prove its existence, based on circulation equations in which the curl of the field is induced by source current density and possibly changes in associated fields. We present an anti-curl operator that is believed novel and we prove that it solves for the field without integration required. 展开更多
关键词 Anti-Derivative Anti-Curl operator Maxwell’s Equations Geometric Calculus Kasner Metric Green’s Function Biot-savart operator
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Determination of the Response Amplitude Operator(s) of an FPSO 被引量:1
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作者 Imabibo Ibinabo Daniel T. Tamunodukobipi 《Engineering(科研)》 2019年第9期541-556,共16页
The driving necessities of cost reduction and the need to develop fields at ever increasing water depths have led to the use of floating structures. Among these structures are the Floating Production Storage and Offlo... The driving necessities of cost reduction and the need to develop fields at ever increasing water depths have led to the use of floating structures. Among these structures are the Floating Production Storage and Offloading (FPSO) units whose motion analysis is considered in this paper. In actual environmental condition, it is required to accurately determine or predict large amplitude motion of the FPSO before any offshore operation. This paper seeks to present a detailed method of computing the Response Amplitude Operator(s) (RAOs) for the six (6) degrees of freedom using ANSYS AQWA. The results indicate for Heave motion a tendency for the heave peak value to move slightly higher dimensionless encounter-frequency as the wave moves from Head sea to Beam sea direction. A MATLAB source code was developed to validate the result for heave motion at head sea. Although a small difference in predicted heave motion occurred, it is pertinent to note that the comparisons between results generated in the MATLAB program and ANSYS AQWA demonstrate generally good agreement, and the roll response of the FPSO is noted to be critical. 展开更多
关键词 REsPONsE AMPLITUDE operator(s) FLOATING Production storage and OFFLOADING Unit ANsYs AQWA MATLAB simplified Method
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The Fuzzy Synthesizing Evaluation of City's Environmental Quality Based on GIOWA Operator:A Case of 13 Cities of Jiangsu Province 被引量:1
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作者 Bai Xianchun 1,2, Ling Kang 2 & Guo Cunzhi 2 1. Institute of Management Science and Engineering, Jinan University, Guangzhou 510632, China 2. Nanjing University of Finance and Economics, School of Economics, Nanjing 210003, China 《Chinese Journal of Population,Resources and Environment》 北大核心 2005年第4期53-60,共8页
In this paper, the generally induced ordered weighted averaging (GIOWA) operator is used to construct the fuzzy evaluating system of the quality of a city’s environment including air, water and noise. Based on the pa... In this paper, the generally induced ordered weighted averaging (GIOWA) operator is used to construct the fuzzy evaluating system of the quality of a city’s environment including air, water and noise. Based on the part data of air, water and noise of the 13 cities under the jurisdiction of Jiangsu provincial government in 2002, a case study is given. The evaluating results show that the evaluating system of the quality of a city’s environment based on the GIOWA operator can reflect the condition of pollution controlled and environmental quality of a city in a period of time. 展开更多
关键词 GIOWA operator city’s environmental quality urbanization.
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Unifying the theory of integration within normal-,Weyl- and antinormal-ordering of operators and the s-ordered operator expansion formula of density operators 被引量:2
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作者 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期41-47,共7页
By introducing the s-parameterized generalized Wigner operator into phase-space quantum mechanics we invent the technique of integration within s-ordered product of operators (which considers normally ordered, antino... By introducing the s-parameterized generalized Wigner operator into phase-space quantum mechanics we invent the technique of integration within s-ordered product of operators (which considers normally ordered, antinormally ordered and Weyl ordered product of operators as its special cases). The s-ordered operator expansion (denoted by s…s ) formula of density operators is derived, which isρ=2/1-s∫d^2β/π〈-β|ρ|β〉sexp{2/s-1(s|β|^2-β*α+βa-αα)}s The s-parameterized quantization scheme is thus completely established. 展开更多
关键词 s-parameterized generalized Wigner operator technique of integration within s-ordered product of operators s-ordered operator expansion formula s-parameterized quantization scheme
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BOUNDEDNESS OF STEIN'S SQUARE FUNCTIONS ASSOCIATED TO OPERATORS ON HARDY SPACES 被引量:1
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作者 闫雪芳 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期891-904,共14页
Let (X, d,μ) be a metric measure space endowed with a metric d and a nonnegative Borel doubling measure μ. Let L be a second order non-negative self-adjoint operator on L^2(X). Assume that the semigroup e^-tL ge... Let (X, d,μ) be a metric measure space endowed with a metric d and a nonnegative Borel doubling measure μ. Let L be a second order non-negative self-adjoint operator on L^2(X). Assume that the semigroup e^-tL generated by L satisfies the Davies-Gaffney estimates. Also, assume that L satisfies Plancherel type estimate. Under these conditions, we show that Stein's square function Gδ(L) arising from Bochner-Riesz means associated to L is bounded from the Hardy spaces HL^p(X) to L^p(X) for all 0 〈 p ≤ 1. 展开更多
关键词 stein's square function non-negative self-adjoint operator Hardy spaces Davies- Gaffney estimate Plancherel type estimate
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Weighted Composition Operators between Hardy Spaces on the Unit Ball 被引量:6
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作者 XUHui-ming LIUTai-shun 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第2期111-119,共9页
We consider the weighted composition operators between Hardy spaces on the unit ball, and obtain some sufficient and necessary conditions of bounded or compact weighted composition operators. We also prove that the op... We consider the weighted composition operators between Hardy spaces on the unit ball, and obtain some sufficient and necessary conditions of bounded or compact weighted composition operators. We also prove that the operator from H^1 to H^1 is compact if and only if it is weakly compact. Meanwhile, we get the analogue on the Bergman spaces. 展开更多
关键词 复变函数 哈代空间 合成算子 几何
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LEIBNIZ′FORMULA OF GENERALIZED DIFFERENCE WITH RESPECT TO A CLASS OF DIFFERENTIAL OPERATORS AND RECURRENCE FORMULA OF THEIR GREEN′S FUNCTION 被引量:1
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作者 许跃生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1984年第3期1359-1364,共6页
In this paper, Leibniz' formula of generalized divided difference with respect to a class of differential operators whose basic sets of solutions have power form, is considered. The recurrence formula of Green fun... In this paper, Leibniz' formula of generalized divided difference with respect to a class of differential operators whose basic sets of solutions have power form, is considered. The recurrence formula of Green function about the operators is also given. 展开更多
关键词 LEIBNIZ s FUNCTION FORMULA OF GENERALIZED DIFFERENCE WITH REsPECT TO A CLAss OF DIFFERENTIAL operators AND RECURRENCE FORMULA OF THEIR GREEN
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基于自适应S面算法的小型ROV艏向和深度运动控制研究
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作者 李国虎 周焕银 《机床与液压》 北大核心 2024年第8期34-38,共5页
带缆遥控水下机器人(ROV)系统艏向与深度运动具有强非线性和运行环境不确定性等特点。针对ROV的运动特点,构建运动控制模型并进行化简,通过构建自适应S面控制法对艏向与深度进行控制,并利用Lyapunov的稳定性判据证明该控制法的稳定性,... 带缆遥控水下机器人(ROV)系统艏向与深度运动具有强非线性和运行环境不确定性等特点。针对ROV的运动特点,构建运动控制模型并进行化简,通过构建自适应S面控制法对艏向与深度进行控制,并利用Lyapunov的稳定性判据证明该控制法的稳定性,通过仿真验证了该控制法具有良好的稳定性和控制品质。同时,与S面控制法相比,自适应S面控制具有更好的动态性能与静态性能,调节速度快、稳定性强,能够准确控制ROV运动。 展开更多
关键词 ROV 自适应s面控制 艏向控制 深度控制
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WEIGHTED COMPOSITION OPERATORS ON WEIGHTED DIRICHLET SPACES 被引量:2
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作者 刘小松 娄增建 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期1119-1126,共8页
We characterize the boundedness and compactness of weighted composition operators on weighted Dirichlet spaces in terms of Nevanlinna counting functions and Caxleson measure.
关键词 weighted composition operator weighted Dirichlet space s-Carleson mea-sure Nevanlinna counting function
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Fractals Generated by Statistical Contraction Operators
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作者 Hu Di\|he School of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期274-280,共7页
In the theory of random fractal, there are two important classes of random sets, one is the class of fractals generated by the paths of stochastic processes and another one is the class of factals generated by statist... In the theory of random fractal, there are two important classes of random sets, one is the class of fractals generated by the paths of stochastic processes and another one is the class of factals generated by statistical contraction operators. Now we will introduce some things about the probability basis and fractal properties of fractals in the last class. The probability basis contains (1) the convergence and measurability of a random recursive setK(ω) as a random element, (2) martingals property. The fractal properties include (3) the character of various similarity, (4) the separability property, (5) the support and zero-one law of distributionP k =P·K ?1, (6) the Hausdorff dimension and Hausdorff exact measure function. 展开更多
关键词 statistical contraction operator FRACTAL statistically self-similar set a. s. self-similar set
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Emerging Phenomenological and Biological Principles of Consciousness: Top Insights of Prevailing Models, Concepts, and Observations
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作者 Ravinder Jerath Connor Beveridge 《World Journal of Neuroscience》 2019年第3期157-190,共34页
We are all aware that our experience is structured into left and right, up and down, and we can understand from our own experience that consciousness is unified into a singular whole. Although we can understand such b... We are all aware that our experience is structured into left and right, up and down, and we can understand from our own experience that consciousness is unified into a singular whole. Although we can understand such basic phenomenological axioms of experience, there are many more principles that we cannot elucidate from our natural perspective alone. In this article, we review potential principles of consciousness revealed by prominent consciousness models, theories, and experimental observations such as the Default Space?Theory, Operational Architectonics Theory, and Integrated Information Theory,?which reveal biological and phenomenological foundations upon which consciousness is formed and maintained. The fundamental concepts we explore and consider worthy have largely emerged from commonalties shared by the various models which have gained attention. The concepts we review include the unity of consciousness, bioelectric operations as the substrate of consciousness, the emergence of a virtual 3D matrix, and the top-down dominance of perception. 展开更多
关键词 DEFAULT space consciousness THALAMUs PERCEPTION operational Architectonics Integrated Information Theory Neural synchrony World simulation
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Enhancing Operational Efficiency: Exploring the Integration of SOPs Using Virtual Reality and Smart Glasses Technology in Food Manufacturing
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作者 Somil Nishar 《Intelligent Control and Automation》 2023年第3期37-44,共8页
This paper explores the integration of Standard Operating Procedures (SOPs) using virtual reality and smart glasses technology in food manufacturing. The study employs a thorough methodology, combining observational i... This paper explores the integration of Standard Operating Procedures (SOPs) using virtual reality and smart glasses technology in food manufacturing. The study employs a thorough methodology, combining observational insights to develop a comprehensive SOP. Implementation at different firms resulted in significant improvements, reducing product waste and enhancing overall efficiency. The use of virtual reality further augments SOP adoption. The findings underscore SOPs’ transformative influence, offering a tangible solution to challenges in the food production sector. Recommendations include regular SOP reviews and ongoing training for sustained success. Different firms exemplify SOPs as indispensable tools for operational excellence. 展开更多
关键词 smart Manufacturing standard operating Procedures 5s six sigma Lean Manufacturing Augmented Reality smart Glasses Food Manufacturing TR Toppers Industry 4.0
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