副支队长是什么级别| 穷途末路什么意思| 贫血吃什么比较好| 糖耐什么时候检查| 四月27日是什么星座| 跳蚤长什么样子| 什么药| 吃东西就打嗝是什么原因| 为什么韩国叫棒子国| 紧急避孕药什么时候吃有效| 牙结石是什么| 缅铃是什么| 蜜糖冲水喝有什么功效| 黄片是什么| 月经正常颜色是什么色| 什么是抖m| 尿检查什么| 2024年属什么| 星期三左眼皮跳是什么预兆| 药店最怕什么样的举报| 髂胫束在什么位置| 打佛七什么意思| 前列腺吃什么药效果好| 重阳节是什么时候| 重阳节吃什么好| 经常吃南瓜有什么好处和坏处| bl小说是什么意思| 涵字取名的寓意是什么| 痔疮吃什么药最好| 大力丸是什么药| 流弹是什么意思| 脚上起水泡是什么原因| 褒姒是什么意思| 滴水观音叶子发黄是什么原因| 绞股蓝有什么功效| 太监是什么意思| 维生素b12是什么| 竞走是什么意思| 血清钙偏高是什么原因| 什么是催眠| 什么的石桥| 蚕豆病不能吃什么药| 梦见被狗咬是什么预兆| 肌肉纤维化是什么意思| ng是什么单位| 去加一笔是什么字| 三高可以吃什么水果| 肾阳虚女性什么症状| 擦伤用什么药好得快| 经常感冒吃什么增强抵抗力| 上午九点多是什么时辰| 吃什么能缓解便秘| warning是什么意思| 狮子座后面是什么星座| 乳头瘙痒是什么原因| u熊是什么意思| 看腋臭挂什么科| 奇门遁甲是什么意思| 荨麻疹是什么原因| fbi相当于中国的什么| 吃刺猬有什么好处| yy什么意思| 汉卿是什么意思| 掌眼什么意思| pr医学上什么意思| 大姨妈吃什么好| 十八罗汉分别叫什么| 牛逼是什么意思| 烫伤抹什么| 胸部ct可以检查出什么| 网织红细胞高说明什么| 阴虚火旺吃什么好| 漂洗和洗涤有什么区别| 肾脏挂什么科| 张什么结什么| 老丈人是什么意思| 内分泌科看什么病| acs是什么| 小孩热感冒吃什么药好| 额头反复长痘是什么原因| 元神是什么意思| 发烧反反复复是什么原因| 打疫苗挂什么科| bp是什么意思| 桉是什么意思| 陶渊明是什么朝代| 下饭是什么意思| 脾胃不好能吃什么水果| cj什么意思| 脸上长痘痘去医院挂什么科| 总梦到一个人说明什么| 调理脾胃吃什么药| 疖肿吃什么药| 好吧是什么意思| 肉偿是什么意思| 巧克力和什么不能一起吃| 寿司用什么米做好吃| mcm是什么牌子| 射精太快吃什么好| 土豆发芽到什么程度不能吃| 左侧淋巴结肿大是什么原因| 有甲状腺结节不能吃什么| 中药什么时候喝效果最好| 一什么家| 蹲马步有什么好处| 眩晕呕吐是什么病| 职称是什么| 眩晕症是什么原因引起的| 脸过敏用什么药膏效果最好| 桃花有什么颜色| 什么食物高蛋白含量高| 抗糖是什么意思| 葡萄糖酸钙锌口服溶液什么时候喝| 大姨妈可以吃什么水果| 血清钙偏高是什么原因| 什么言| 嫡是什么意思| 小孩什么时候说话| 震卦代表什么| 清胃火吃什么药| 肌酐低什么原因| 慢性胆囊炎吃什么药| 女性性冷淡是什么原因| 老人脚肿吃什么药消肿| 性格缺陷是什么意思| 支气管炎咳嗽吃什么药好得快| 羟苯乙酯是什么东西| 压床是什么意思| 烤冷面是什么做的| 江诗丹顿是什么档次| 7月13日是什么日子| cpb是什么意思| 皮肤黑穿什么颜色的衣服显白| 归来是什么意思| 阎王叫什么| 蓝本是什么意思| 小透明是什么意思| 什么时候割包皮最好| 银杏叶是什么颜色| 缓刑什么意思| bnp是什么检查| 指甲横纹是什么原因| Valentino什么牌子| 吃什么能增加免疫力| 233什么意思| 人中深浅代表什么| 大肠杆菌属于什么菌| 属马与什么属相最配| 胃烧心是什么症状| 1930年属什么生肖| ca19-9偏高是什么意思| 胃疼吃什么药好| 十一月七号是什么星座| 乐果是什么农药| 大眼角痒用什么眼药水| 秦始皇叫什么名字| 什么是花胶| h1v是什么病| 1941年是什么年| 外阴瘙痒用什么药| 嬴稷是秦始皇的什么人| 耳朵闷闷的堵住的感觉是什么原因| 丙肝为什么会自愈| 湿疹是什么皮肤病| 秋分节气的含义是什么| 甜字五行属什么| 经常拉稀是什么原因| 血压低头晕是什么原因导致的| 消症是什么意思| 活着的意义是什么| 高频听力损失意味什么| 胎位不正是什么原因导致的| 人中跳动是什么原因| 什么是肺纤维化| 梦女是什么意思| 理想主义者是什么意思| 心火旺喝什么茶| 谷氨酰胺是什么| 什么汤好喝又简单| 巨大的什么| 处方药是什么意思| 小麦淀粉是什么| 宫颈肥大有什么症状| 常吃山药有什么好处和坏处| 勤去掉力念什么| 为什么星星会眨眼| 沉的右边念什么| 甲状腺做什么检查| 922是什么星座| 肠胃不好喝什么奶粉好| 甲沟炎挂什么科| 年少轻狂是什么意思| 肝囊肿是什么病| 鳖吃什么| 诗情画意的意思是什么| 小腿抽筋是什么原因引起的| 西瓜虫吃什么食物| 澳门打车用什么软件| 梦见做被子什么意思| 脉压是什么意思| 行代表什么生肖| 脱盐乳清粉是什么| 秋水长天什么意思| 梦见经血是什么预兆| 冲鸡蛋水喝有什么好处| 人体第一道防线是什么| 钾高了会出现什么症状| le是什么| 小孩有口臭是什么原因引起的| 基底是什么意思| 什么样的雨珠| 仓鼠吃什么| 一什么麦子| 头晕看什么科| 铁剂不能与什么同服| 早上五点半是什么时辰| 女生胸部什么时候停止发育| 坐以待毙是什么意思| 什么去甲醛最快有效| 戈美其鞋子是什么档次| cr是什么金属| 为什么腋窝老是出汗| 科学是什么| 落班是什么意思| 端着是什么意思| 为什么湿气重| 血脂高可以吃什么水果| 衣带渐宽终不悔是什么意思| 老日念什么| jewelry什么意思| nov是什么意思| 女人湿气太重喝什么茶| 尿常规检查挂什么科| 本科是什么意思| 玉髓是什么材质| 腺肌瘤是什么病| 拔罐出水是什么原因| 你最喜欢的食物是什么| 睡觉容易惊醒是什么原因| 谷雨是什么意思| 最近发胖过快什么原因| 发烧流鼻血是什么原因| 92年出生属什么| 什么是远视| 闷骚男是什么意思| 痤疮用什么药| 1972年出生属什么生肖| 腹直肌分离是什么意思| 文化大革命什么时候结束| 夜间盗汗是什么原因| 二月什么座| rapido是什么牌子| 黄水疮用什么药膏最快| 穆赫兰道到底讲的什么| 麻小是什么意思| 砂舞是什么意思| 院士是什么级别| 寒露是什么季节| 什么食物含钾高| 临官是什么意思| 肩周炎挂什么科室| 岍是什么意思| 4月20日是什么星座| 阴囊潮湿什么原因| 百度Jump to content

妻子偷偷借下785万巨债 去世后丈夫免责不用还

From Wikipedia, the free encyclopedia
Graph of a surface given by z = f(x, y) = ?(x2 + y2) + 4. The global maximum at (x, y, z) = (0, 0, 4) is indicated by a blue dot.
Nelder-Mead minimum search of Simionescu's function. Simplex vertices are ordered by their values, with 1 having the lowest ( best) value.
百度 坚持目标导向,把中央和省、市委的重大决策部署和各项任务落到实处。

Mathematical optimization (alternatively spelled optimisation) or mathematical programming is the selection of a best element, with regard to some criteria, from some set of available alternatives.[1][2] It is generally divided into two subfields: discrete optimization and continuous optimization. Optimization problems arise in all quantitative disciplines from computer science and engineering[3] to operations research and economics, and the development of solution methods has been of interest in mathematics for centuries.[4]

In the more general approach, an optimization problem consists of maximizing or minimizing a real function by systematically choosing input values from within an allowed set and computing the value of the function. The generalization of optimization theory and techniques to other formulations constitutes a large area of applied mathematics.

Optimization problems

[edit]

Optimization problems can be divided into two categories, depending on whether the variables are continuous or discrete:

An optimization problem can be represented in the following way:

Given: a function from some set A to the real numbers
Sought: an element x0A such that f(x0) ≤ f(x) for all xA ("minimization") or such that f(x0) ≥ f(x) for all xA ("maximization").

Such a formulation is called an optimization problem or a mathematical programming problem (a term not directly related to computer programming, but still in use for example in linear programming – see History below). Many real-world and theoretical problems may be modeled in this general framework.

Since the following is valid:

it suffices to solve only minimization problems. However, the opposite perspective of considering only maximization problems would be valid, too.

Problems formulated using this technique in the fields of physics may refer to the technique as energy minimization,[5] speaking of the value of the function f as representing the energy of the system being modeled. In machine learning, it is always necessary to continuously evaluate the quality of a data model by using a cost function where a minimum implies a set of possibly optimal parameters with an optimal (lowest) error.

Typically, A is some subset of the Euclidean space , often specified by a set of constraints, equalities or inequalities that the members of A have to satisfy. The domain A of f is called the search space or the choice set, while the elements of A are called candidate solutions or feasible solutions.

The function f is variously called an objective function, criterion function, loss function, cost function (minimization),[6] utility function or fitness function (maximization), or, in certain fields, an energy function or energy functional. A feasible solution that minimizes (or maximizes) the objective function is called an optimal solution.

In mathematics, conventional optimization problems are usually stated in terms of minimization.

A local minimum x* is defined as an element for which there exists some δ > 0 such that

the expression f(x*) ≤ f(x) holds;

that is to say, on some region around x* all of the function values are greater than or equal to the value at that element. Local maxima are defined similarly.

While a local minimum is at least as good as any nearby elements, a global minimum is at least as good as every feasible element. Generally, unless the objective function is convex in a minimization problem, there may be several local minima. In a convex problem, if there is a local minimum that is interior (not on the edge of the set of feasible elements), it is also the global minimum, but a nonconvex problem may have more than one local minimum not all of which need be global minima.

A large number of algorithms proposed for solving the nonconvex problems – including the majority of commercially available solvers – are not capable of making a distinction between locally optimal solutions and globally optimal solutions, and will treat the former as actual solutions to the original problem. Global optimization is the branch of applied mathematics and numerical analysis that is concerned with the development of deterministic algorithms that are capable of guaranteeing convergence in finite time to the actual optimal solution of a nonconvex problem.

Notation

[edit]

Optimization problems are often expressed with special notation. Here are some examples:

Minimum and maximum value of a function

[edit]

Consider the following notation:

This denotes the minimum value of the objective function x2 + 1, when choosing x from the set of real numbers . The minimum value in this case is 1, occurring at x = 0.

Similarly, the notation

asks for the maximum value of the objective function 2x, where x may be any real number. In this case, there is no such maximum as the objective function is unbounded, so the answer is "infinity" or "undefined".

Optimal input arguments

[edit]

Consider the following notation:

or equivalently

This represents the value (or values) of the argument x in the interval (?∞,?1] that minimizes (or minimize) the objective function x2 + 1 (the actual minimum value of that function is not what the problem asks for). In this case, the answer is x = ?1, since x = 0 is infeasible, that is, it does not belong to the feasible set.

Similarly,

or equivalently

represents the {x, y} pair (or pairs) that maximizes (or maximize) the value of the objective function x cos y, with the added constraint that x lie in the interval [?5,5] (again, the actual maximum value of the expression does not matter). In this case, the solutions are the pairs of the form {5, 2kπ} and {?5, (2k + 1)π}, where k ranges over all integers.

Operators arg min and arg max are sometimes also written as argmin and argmax, and stand for argument of the minimum and argument of the maximum.

History

[edit]

Fermat and Lagrange found calculus-based formulae for identifying optima, while Newton and Gauss proposed iterative methods for moving towards an optimum.

The term "linear programming" for certain optimization cases was due to George B. Dantzig, although much of the theory had been introduced by Leonid Kantorovich in 1939. (Programming in this context does not refer to computer programming, but comes from the use of program by the United States military to refer to proposed training and logistics schedules, which were the problems Dantzig studied at that time.) Dantzig published the Simplex algorithm in 1947, and also John von Neumann and other researchers worked on the theoretical aspects of linear programming (like the theory of duality) around the same time.[7]

Other notable researchers in mathematical optimization include the following:

Major subfields

[edit]
  • Convex programming studies the case when the objective function is convex (minimization) or concave (maximization) and the constraint set is convex. This can be viewed as a particular case of nonlinear programming or as generalization of linear or convex quadratic programming.
    • Linear programming (LP), a type of convex programming, studies the case in which the objective function f is linear and the constraints are specified using only linear equalities and inequalities. Such a constraint set is called a polyhedron or a polytope if it is bounded.
    • Second-order cone programming (SOCP) is a convex program, and includes certain types of quadratic programs.
    • Semidefinite programming (SDP) is a subfield of convex optimization where the underlying variables are semidefinite matrices. It is a generalization of linear and convex quadratic programming.
    • Conic programming is a general form of convex programming. LP, SOCP and SDP can all be viewed as conic programs with the appropriate type of cone.
    • Geometric programming is a technique whereby objective and inequality constraints expressed as posynomials and equality constraints as monomials can be transformed into a convex program.
  • Integer programming studies linear programs in which some or all variables are constrained to take on integer values. This is not convex, and in general much more difficult than regular linear programming.
  • Quadratic programming allows the objective function to have quadratic terms, while the feasible set must be specified with linear equalities and inequalities. For specific forms of the quadratic term, this is a type of convex programming.
  • Fractional programming studies optimization of ratios of two nonlinear functions. The special class of concave fractional programs can be transformed to a convex optimization problem.
  • Nonlinear programming studies the general case in which the objective function or the constraints or both contain nonlinear parts. This may or may not be a convex program. In general, whether the program is convex affects the difficulty of solving it.
  • Stochastic programming studies the case in which some of the constraints or parameters depend on random variables.
  • Robust optimization is, like stochastic programming, an attempt to capture uncertainty in the data underlying the optimization problem. Robust optimization aims to find solutions that are valid under all possible realizations of the uncertainties defined by an uncertainty set.
  • Combinatorial optimization is concerned with problems where the set of feasible solutions is discrete or can be reduced to a discrete one.
  • Stochastic optimization is used with random (noisy) function measurements or random inputs in the search process.
  • Infinite-dimensional optimization studies the case when the set of feasible solutions is a subset of an infinite-dimensional space, such as a space of functions.
  • Heuristics and metaheuristics make few or no assumptions about the problem being optimized. Usually, heuristics do not guarantee that any optimal solution need be found. On the other hand, heuristics are used to find approximate solutions for many complicated optimization problems.
  • Constraint satisfaction studies the case in which the objective function f is constant (this is used in artificial intelligence, particularly in automated reasoning).
    • Constraint programming is a programming paradigm wherein relations between variables are stated in the form of constraints.
  • Disjunctive programming is used where at least one constraint must be satisfied but not all. It is of particular use in scheduling.
  • Space mapping is a concept for modeling and optimization of an engineering system to high-fidelity (fine) model accuracy exploiting a suitable physically meaningful coarse or surrogate model.

In a number of subfields, the techniques are designed primarily for optimization in dynamic contexts (that is, decision making over time):

Multi-objective optimization

[edit]

Adding more than one objective to an optimization problem adds complexity. For example, to optimize a structural design, one would desire a design that is both light and rigid. When two objectives conflict, a trade-off must be created. There may be one lightest design, one stiffest design, and an infinite number of designs that are some compromise of weight and rigidity. The set of trade-off designs that improve upon one criterion at the expense of another is known as the Pareto set. The curve created plotting weight against stiffness of the best designs is known as the Pareto frontier.

A design is judged to be "Pareto optimal" (equivalently, "Pareto efficient" or in the Pareto set) if it is not dominated by any other design: If it is worse than another design in some respects and no better in any respect, then it is dominated and is not Pareto optimal.

The choice among "Pareto optimal" solutions to determine the "favorite solution" is delegated to the decision maker. In other words, defining the problem as multi-objective optimization signals that some information is missing: desirable objectives are given but combinations of them are not rated relative to each other. In some cases, the missing information can be derived by interactive sessions with the decision maker.

Multi-objective optimization problems have been generalized further into vector optimization problems where the (partial) ordering is no longer given by the Pareto ordering.

Multi-modal or global optimization

[edit]

Optimization problems are often multi-modal; that is, they possess multiple good solutions. They could all be globally good (same cost function value) or there could be a mix of globally good and locally good solutions. Obtaining all (or at least some of) the multiple solutions is the goal of a multi-modal optimizer.

Classical optimization techniques due to their iterative approach do not perform satisfactorily when they are used to obtain multiple solutions, since it is not guaranteed that different solutions will be obtained even with different starting points in multiple runs of the algorithm.

Common approaches to global optimization problems, where multiple local extrema may be present include evolutionary algorithms, Bayesian optimization and simulated annealing.

Classification of critical points and extrema

[edit]

Feasibility problem

[edit]

The satisfiability problem, also called the feasibility problem, is just the problem of finding any feasible solution at all without regard to objective value. This can be regarded as the special case of mathematical optimization where the objective value is the same for every solution, and thus any solution is optimal.

Many optimization algorithms need to start from a feasible point. One way to obtain such a point is to relax the feasibility conditions using a slack variable; with enough slack, any starting point is feasible. Then, minimize that slack variable until the slack is null or negative.

Existence

[edit]

The extreme value theorem of Karl Weierstrass states that a continuous real-valued function on a compact set attains its maximum and minimum value. More generally, a lower semi-continuous function on a compact set attains its minimum; an upper semi-continuous function on a compact set attains its maximum point or view.

Necessary conditions for optimality

[edit]

One of Fermat's theorems states that optima of unconstrained problems are found at stationary points, where the first derivative or the gradient of the objective function is zero (see first derivative test). More generally, they may be found at critical points, where the first derivative or gradient of the objective function is zero or is undefined, or on the boundary of the choice set. An equation (or set of equations) stating that the first derivative(s) equal(s) zero at an interior optimum is called a 'first-order condition' or a set of first-order conditions.

Optima of equality-constrained problems can be found by the Lagrange multiplier method. The optima of problems with equality and/or inequality constraints can be found using the 'Karush–Kuhn–Tucker conditions'.

Sufficient conditions for optimality

[edit]

While the first derivative test identifies points that might be extrema, this test does not distinguish a point that is a minimum from one that is a maximum or one that is neither. When the objective function is twice differentiable, these cases can be distinguished by checking the second derivative or the matrix of second derivatives (called the Hessian matrix) in unconstrained problems, or the matrix of second derivatives of the objective function and the constraints called the bordered Hessian in constrained problems. The conditions that distinguish maxima, or minima, from other stationary points are called 'second-order conditions' (see 'Second derivative test'). If a candidate solution satisfies the first-order conditions, then the satisfaction of the second-order conditions as well is sufficient to establish at least local optimality.

Sensitivity and continuity of optima

[edit]

The envelope theorem describes how the value of an optimal solution changes when an underlying parameter changes. The process of computing this change is called comparative statics.

The maximum theorem of Claude Berge (1963) describes the continuity of an optimal solution as a function of underlying parameters.

Calculus of optimization

[edit]

For unconstrained problems with twice-differentiable functions, some critical points can be found by finding the points where the gradient of the objective function is zero (that is, the stationary points). More generally, a zero subgradient certifies that a local minimum has been found for minimization problems with convex functions and other locally Lipschitz functions, which meet in loss function minimization of the neural network. The positive-negative momentum estimation lets to avoid the local minimum and converges at the objective function global minimum.[8]

Further, critical points can be classified using the definiteness of the Hessian matrix: If the Hessian is positive definite at a critical point, then the point is a local minimum; if the Hessian matrix is negative definite, then the point is a local maximum; finally, if indefinite, then the point is some kind of saddle point.

Constrained problems can often be transformed into unconstrained problems with the help of Lagrange multipliers. Lagrangian relaxation can also provide approximate solutions to difficult constrained problems.

When the objective function is a convex function, then any local minimum will also be a global minimum. There exist efficient numerical techniques for minimizing convex functions, such as interior-point methods.

Global convergence

[edit]

More generally, if the objective function is not a quadratic function, then many optimization methods use other methods to ensure that some subsequence of iterations converges to an optimal solution. The first and still popular method for ensuring convergence relies on line searches, which optimize a function along one dimension. A second and increasingly popular method for ensuring convergence uses trust regions. Both line searches and trust regions are used in modern methods of non-differentiable optimization. Usually, a global optimizer is much slower than advanced local optimizers (such as BFGS), so often an efficient global optimizer can be constructed by starting the local optimizer from different starting points.

Computational optimization techniques

[edit]

To solve problems, researchers may use algorithms that terminate in a finite number of steps, or iterative methods that converge to a solution (on some specified class of problems), or heuristics that may provide approximate solutions to some problems (although their iterates need not converge).

Optimization algorithms

[edit]

Iterative methods

[edit]

The iterative methods used to solve problems of nonlinear programming differ according to whether they evaluate Hessians, gradients, or only function values. While evaluating Hessians (H) and gradients (G) improves the rate of convergence, for functions for which these quantities exist and vary sufficiently smoothly, such evaluations increase the computational complexity (or computational cost) of each iteration. In some cases, the computational complexity may be excessively high.

One major criterion for optimizers is just the number of required function evaluations as this often is already a large computational effort, usually much more effort than within the optimizer itself, which mainly has to operate over the N variables. The derivatives provide detailed information for such optimizers, but are even harder to calculate, e.g. approximating the gradient takes at least N+1 function evaluations. For approximations of the 2nd derivatives (collected in the Hessian matrix), the number of function evaluations is in the order of N2. Newton's method requires the 2nd-order derivatives, so for each iteration, the number of function calls is in the order of N2, but for a simpler pure gradient optimizer it is only N. However, gradient optimizers need usually more iterations than Newton's algorithm. Which one is best with respect to the number of function calls depends on the problem itself.

  • Methods that evaluate Hessians (or approximate Hessians, using finite differences):
    • Newton's method
    • Sequential quadratic programming: A Newton-based method for small-medium scale constrained problems. Some versions can handle large-dimensional problems.
    • Interior point methods: This is a large class of methods for constrained optimization, some of which use only (sub)gradient information and others of which require the evaluation of Hessians.
  • Methods that evaluate gradients, or approximate gradients in some way (or even subgradients):
    • Coordinate descent methods: Algorithms which update a single coordinate in each iteration
    • Conjugate gradient methods: Iterative methods for large problems. (In theory, these methods terminate in a finite number of steps with quadratic objective functions, but this finite termination is not observed in practice on finite–precision computers.)
    • Gradient descent (alternatively, "steepest descent" or "steepest ascent"): A (slow) method of historical and theoretical interest, which has had renewed interest for finding approximate solutions of enormous problems.
    • Subgradient methods: An iterative method for large locally Lipschitz functions using generalized gradients. Following Boris T. Polyak, subgradient–projection methods are similar to conjugate–gradient methods.
    • Bundle method of descent: An iterative method for small–medium-sized problems with locally Lipschitz functions, particularly for convex minimization problems (similar to conjugate gradient methods).
    • Ellipsoid method: An iterative method for small problems with quasiconvex objective functions and of great theoretical interest, particularly in establishing the polynomial time complexity of some combinatorial optimization problems. It has similarities with Quasi-Newton methods.
    • Conditional gradient method (Frank–Wolfe) for approximate minimization of specially structured problems with linear constraints, especially with traffic networks. For general unconstrained problems, this method reduces to the gradient method, which is regarded as obsolete (for almost all problems).
    • Quasi-Newton methods: Iterative methods for medium-large problems (e.g. N<1000).
    • Simultaneous perturbation stochastic approximation (SPSA) method for stochastic optimization; uses random (efficient) gradient approximation.
  • Methods that evaluate only function values: If a problem is continuously differentiable, then gradients can be approximated using finite differences, in which case a gradient-based method can be used.

Heuristics

[edit]

Besides (finitely terminating) algorithms and (convergent) iterative methods, there are heuristics. A heuristic is any algorithm which is not guaranteed (mathematically) to find the solution, but which is nevertheless useful in certain practical situations. List of some well-known heuristics:

Applications

[edit]

Mechanics

[edit]

Problems in rigid body dynamics (in particular articulated rigid body dynamics) often require mathematical programming techniques, since you can view rigid body dynamics as attempting to solve an ordinary differential equation on a constraint manifold;[9] the constraints are various nonlinear geometric constraints such as "these two points must always coincide", "this surface must not penetrate any other", or "this point must always lie somewhere on this curve". Also, the problem of computing contact forces can be done by solving a linear complementarity problem, which can also be viewed as a QP (quadratic programming) problem.

Many design problems can also be expressed as optimization programs. This application is called design optimization. One subset is the engineering optimization, and another recent and growing subset of this field is multidisciplinary design optimization, which, while useful in many problems, has in particular been applied to aerospace engineering problems.

This approach may be applied in cosmology and astrophysics.[10]

Economics and finance

[edit]

Economics is closely enough linked to optimization of agents that an influential definition relatedly describes economics qua science as the "study of human behavior as a relationship between ends and scarce means" with alternative uses.[11] Modern optimization theory includes traditional optimization theory but also overlaps with game theory and the study of economic equilibria. The Journal of Economic Literature codes classify mathematical programming, optimization techniques, and related topics under JEL:C61-C63.

In microeconomics, the utility maximization problem and its dual problem, the expenditure minimization problem, are economic optimization problems. Insofar as they behave consistently, consumers are assumed to maximize their utility, while firms are usually assumed to maximize their profit. Also, agents are often modeled as being risk-averse, thereby preferring to avoid risk. Asset prices are also modeled using optimization theory, though the underlying mathematics relies on optimizing stochastic processes rather than on static optimization. International trade theory also uses optimization to explain trade patterns between nations. The optimization of portfolios is an example of multi-objective optimization in economics.

Since the 1970s, economists have modeled dynamic decisions over time using control theory.[12] For example, dynamic search models are used to study labor-market behavior.[13] A crucial distinction is between deterministic and stochastic models.[14] Macroeconomists build dynamic stochastic general equilibrium (DSGE) models that describe the dynamics of the whole economy as the result of the interdependent optimizing decisions of workers, consumers, investors, and governments.[15][16]

Electrical engineering

[edit]

Some common applications of optimization techniques in electrical engineering include active filter design,[17] stray field reduction in superconducting magnetic energy storage systems, space mapping design of microwave structures,[18] handset antennas,[19][20][21] electromagnetics-based design. Electromagnetically validated design optimization of microwave components and antennas has made extensive use of an appropriate physics-based or empirical surrogate model and space mapping methodologies since the discovery of space mapping in 1993.[22][23] Optimization techniques are also used in power-flow analysis.[24]

Civil engineering

[edit]

Optimization has been widely used in civil engineering. Construction management and transportation engineering are among the main branches of civil engineering that heavily rely on optimization. The most common civil engineering problems that are solved by optimization are cut and fill of roads, life-cycle analysis of structures and infrastructures,[25] resource leveling,[26][27] water resource allocation, traffic management[28] and schedule optimization.

Operations research

[edit]

Another field that uses optimization techniques extensively is operations research.[29] Operations research also uses stochastic modeling and simulation to support improved decision-making. Increasingly, operations research uses stochastic programming to model dynamic decisions that adapt to events; such problems can be solved with large-scale optimization and stochastic optimization methods.

Control engineering

[edit]

Mathematical optimization is used in much modern controller design. High-level controllers such as model predictive control (MPC) or real-time optimization (RTO) employ mathematical optimization. These algorithms run online and repeatedly determine values for decision variables, such as choke openings in a process plant, by iteratively solving a mathematical optimization problem including constraints and a model of the system to be controlled.

Geophysics

[edit]

Optimization techniques are regularly used in geophysical parameter estimation problems. Given a set of geophysical measurements, e.g. seismic recordings, it is common to solve for the physical properties and geometrical shapes of the underlying rocks and fluids. The majority of problems in geophysics are nonlinear with both deterministic and stochastic methods being widely used.

Molecular modeling

[edit]

Nonlinear optimization methods are widely used in conformational analysis.

Computational systems biology

[edit]

Optimization techniques are used in many facets of computational systems biology such as model building, optimal experimental design, metabolic engineering, and synthetic biology.[30] Linear programming has been applied to calculate the maximal possible yields of fermentation products,[30] and to infer gene regulatory networks from multiple microarray datasets[31] as well as transcriptional regulatory networks from high-throughput data.[32] Nonlinear programming has been used to analyze energy metabolism[33] and has been applied to metabolic engineering and parameter estimation in biochemical pathways.[34]

Machine learning

[edit]

Solvers

[edit]

See also

[edit]

Notes

[edit]
  1. ^ "The Nature of Mathematical Programming Archived 2025-08-06 at the Wayback Machine," Mathematical Programming Glossary, INFORMS Computing Society.
  2. ^ "Mathematical Programming: An Overview" (PDF). Retrieved 26 April 2024.
  3. ^ Martins, Joaquim R. R. A.; Ning, Andrew (2025-08-06). Engineering Design Optimization. Cambridge University Press. ISBN 978-1108833417.
  4. ^ Du, D. Z.; Pardalos, P. M.; Wu, W. (2008). "History of Optimization". In Floudas, C.; Pardalos, P. (eds.). Encyclopedia of Optimization. Boston: Springer. pp. 1538–1542.
  5. ^ Hartmann, Alexander K; Rieger, Heiko (2002). Optimization algorithms in physics. Citeseer.
  6. ^ Erwin Diewert, W. (2017), "Cost Functions", The New Palgrave Dictionary of Economics, London: Palgrave Macmillan UK, pp. 1–12, doi:10.1057/978-1-349-95121-5_659-2, ISBN 978-1-349-95121-5, retrieved 2025-08-06
  7. ^ Bixby, Robert E (2012). "A brief history of linear and mixed-integer programming computation" (PDF). Documenta Mathematica. Documenta Mathematica Series. 2012: 107–121. doi:10.4171/dms/6/16. ISBN 978-3-936609-58-5.
  8. ^ Abdulkadirov, R.; Lyakhov, P.; Bergerman, M.; Reznikov, D. (February 2024). "Satellite image recognition using ensemble neural networks and difference gradient positive-negative momentum". Chaos, Solitons & Fractals. 179 114432. Bibcode:2024CSF...17914432A. doi:10.1016/j.chaos.2023.114432.
  9. ^ Vereshchagin, A.F. (1989). "Modelling and control of motion of manipulation robots". Soviet Journal of Computer and Systems Sciences. 27 (5): 29–38.
  10. ^ Haggag, S.; Desokey, F.; Ramadan, M. (2017). "A cosmological inflationary model using optimal control". Gravitation and Cosmology. 23 (3): 236–239. Bibcode:2017GrCo...23..236H. doi:10.1134/S0202289317030069. ISSN 1995-0721. S2CID 125980981.
  11. ^ Lionel Robbins (1935, 2nd ed.) An Essay on the Nature and Significance of Economic Science, Macmillan, p. 16.
  12. ^ Dorfman, Robert (1969). "An Economic Interpretation of Optimal Control Theory". American Economic Review. 59 (5): 817–831. JSTOR 1810679.
  13. ^ Sargent, Thomas J. (1987). "Search". Dynamic Macroeconomic Theory. Harvard University Press. pp. 57–91. ISBN 9780674043084.
  14. ^ A.G. Malliaris (2008). "stochastic optimal control," The New Palgrave Dictionary of Economics, 2nd Edition. Abstract Archived 2025-08-06 at the Wayback Machine.
  15. ^ Rotemberg, Julio; Woodford, Michael (1997). "An Optimization-based Econometric Framework for the Evaluation of Monetary Policy" (PDF). NBER Macroeconomics Annual. 12: 297–346. doi:10.2307/3585236. JSTOR 3585236.
  16. ^ From The New Palgrave Dictionary of Economics (2008), 2nd Edition with Abstract links:
    ? "numerical optimization methods in economics" by Karl Schmedders
    ? "convex programming" by Lawrence E. Blume
    ? "Arrow–Debreu model of general equilibrium" by John Geanakoplos.
  17. ^ De, Bishnu Prasad; Kar, R.; Mandal, D.; Ghoshal, S.P. (2025-08-06). "Optimal selection of components value for analog active filter design using simplex particle swarm optimization". International Journal of Machine Learning and Cybernetics. 6 (4): 621–636. doi:10.1007/s13042-014-0299-0. ISSN 1868-8071. S2CID 13071135.
  18. ^ Koziel, Slawomir; Bandler, John W. (January 2008). "Space Mapping With Multiple Coarse Models for Optimization of Microwave Components". IEEE Microwave and Wireless Components Letters. 18 (1): 1–3. Bibcode:2008IMWCL..18L1969K. CiteSeerX 10.1.1.147.5407. doi:10.1109/LMWC.2007.911969. S2CID 11086218.
  19. ^ Tu, Sheng; Cheng, Qingsha S.; Zhang, Yifan; Bandler, John W.; Nikolova, Natalia K. (July 2013). "Space Mapping Optimization of Handset Antennas Exploiting Thin-Wire Models". IEEE Transactions on Antennas and Propagation. 61 (7): 3797–3807. Bibcode:2013ITAP...61.3797T. doi:10.1109/TAP.2013.2254695.
  20. ^ N. Friedrich, “Space mapping outpaces EM optimization in handset-antenna design,” microwaves&rf, August 30, 2013.
  21. ^ Cervantes-González, Juan C.; Rayas-Sánchez, José E.; López, Carlos A.; Camacho-Pérez, José R.; Brito-Brito, Zabdiel; Chávez-Hurtado, José L. (February 2016). "Space mapping optimization of handset antennas considering EM effects of mobile phone components and human body". International Journal of RF and Microwave Computer-Aided Engineering. 26 (2): 121–128. doi:10.1002/mmce.20945. S2CID 110195165.
  22. ^ Bandler, J.W.; Biernacki, R.M.; Chen, Shao Hua; Grobelny, P.A.; Hemmers, R.H. (1994). "Space mapping technique for electromagnetic optimization". IEEE Transactions on Microwave Theory and Techniques. 42 (12): 2536–2544. Bibcode:1994ITMTT..42.2536B. doi:10.1109/22.339794.
  23. ^ Bandler, J.W.; Biernacki, R.M.; Shao Hua Chen; Hemmers, R.H.; Madsen, K. (1995). "Electromagnetic optimization exploiting aggressive space mapping". IEEE Transactions on Microwave Theory and Techniques. 43 (12): 2874–2882. Bibcode:1995ITMTT..43.2874B. doi:10.1109/22.475649.
  24. ^ Convex relaxation of optimal power flow: A tutorial. 2013 iREP Symposium on Bulk Power System Dynamics and Control. doi:10.1109/IREP.2013.6629391.
  25. ^ Piryonesi, Sayed Madeh; Tavakolan, Mehdi (9 January 2017). "A mathematical programming model for solving cost-safety optimization (CSO) problems in the maintenance of structures". KSCE Journal of Civil Engineering. 21 (6): 2226–2234. Bibcode:2017KSJCE..21.2226P. doi:10.1007/s12205-017-0531-z. S2CID 113616284.
  26. ^ Hegazy, Tarek (June 1999). "Optimization of Resource Allocation and Leveling Using Genetic Algorithms". Journal of Construction Engineering and Management. 125 (3): 167–175. doi:10.1061/(ASCE)0733-9364(1999)125:3(167).
  27. ^ Piryonesi, S. Madeh; Nasseri, Mehran; Ramezani, Abdollah (9 July 2018). "Piryonesi, S. M., Nasseri, M., & Ramezani, A. (2018). Resource leveling in construction projects with activity splitting and resource constraints: a simulated annealing optimization". Canadian Journal of Civil Engineering. 46: 81–86. doi:10.1139/cjce-2017-0670. hdl:1807/93364. S2CID 116480238.
  28. ^ Herty, M.; Klar, A. (2025-08-06). "Modeling, Simulation, and Optimization of Traffic Flow Networks". SIAM Journal on Scientific Computing. 25 (3): 1066–1087. Bibcode:2003SJSC...25.1066H. doi:10.1137/S106482750241459X. ISSN 1064-8275.
  29. ^ "New force on the political scene: the Seophonisten". Archived from the original on 18 December 2014. Retrieved 14 September 2013.
  30. ^ a b Papoutsakis, Eleftherios Terry (February 1984). "Equations and calculations for fermentations of butyric acid bacteria". Biotechnology and Bioengineering. 26 (2): 174–187. Bibcode:1984BiotB..26..174P. doi:10.1002/bit.260260210. ISSN 0006-3592. PMID 18551704. S2CID 25023799.
  31. ^ Wang, Yong; Joshi, Trupti; Zhang, Xiang-Sun; Xu, Dong; Chen, Luonan (2025-08-06). "Inferring gene regulatory networks from multiple microarray datasets". Bioinformatics. 22 (19): 2413–2420. doi:10.1093/bioinformatics/btl396. ISSN 1460-2059. PMID 16864593.
  32. ^ Wang, Rui-Sheng; Wang, Yong; Zhang, Xiang-Sun; Chen, Luonan (2025-08-06). "Inferring transcriptional regulatory networks from high-throughput data". Bioinformatics. 23 (22): 3056–3064. doi:10.1093/bioinformatics/btm465. ISSN 1460-2059. PMID 17890736.
  33. ^ Vo, Thuy D.; Paul Lee, W.N.; Palsson, Bernhard O. (May 2007). "Systems analysis of energy metabolism elucidates the affected respiratory chain complex in Leigh's syndrome". Molecular Genetics and Metabolism. 91 (1): 15–22. doi:10.1016/j.ymgme.2007.01.012. ISSN 1096-7192. PMID 17336115.
  34. ^ Mendes, P.; Kell, D. (1998). "Non-linear optimization of biochemical pathways: applications to metabolic engineering and parameter estimation". Bioinformatics. 14 (10): 869–883. doi:10.1093/bioinformatics/14.10.869. ISSN 1367-4803. PMID 9927716.

Further reading

[edit]
  • Boyd, Stephen P.; Vandenberghe, Lieven (2004). Convex Optimization. Cambridge: Cambridge University Press. ISBN 0-521-83378-7.
  • Gill, P. E.; Murray, W.; Wright, M. H. (1982). Practical Optimization. London: Academic Press. ISBN 0-12-283952-8.
  • Lee, Jon (2004). A First Course in Combinatorial Optimization. Cambridge University Press. ISBN 0-521-01012-8.
  • Nocedal, Jorge; Wright, Stephen J. (2006). Numerical Optimization (2nd ed.). Berlin: Springer. ISBN 0-387-30303-0.
  • G.L. Nemhauser, A.H.G. Rinnooy Kan and M.J. Todd (eds.): Optimization, Elsevier, (1989).
  • Stanislav Walukiewicz:Integer Programming, Springer,ISBN 978-9048140688, (1990).
  • R. Fletcher: Practical Methods of Optimization, 2nd Ed., Wiley, (2000).
  • Panos M. Pardalos:Approximation and Complexity in Numerical Optimization: Continuous and Discrete Problems, Springer,ISBN 978-1-44194829-8, (2000).
  • Xiaoqi Yang, K. L. Teo, Lou Caccetta (Eds.):Optimization Methods and Applications,Springer, ISBN 978-0-79236866-3, (2001).
  • Panos M. Pardalos, and Mauricio G. C. Resende(Eds.):Handbook of Applied Optimization、Oxford Univ Pr on Demand, ISBN 978-0-19512594-8, (2002).
  • Wil Michiels, Emile Aarts, and Jan Korst: Theoretical Aspects of Local Search, Springer, ISBN 978-3-64207148-5, (2006).
  • Der-San Chen, Robert G. Batson, and Yu Dang: Applied Integer Programming: Modeling and Solution,Wiley,ISBN 978-0-47037306-4, (2010).
  • Mykel J. Kochenderfer and Tim A. Wheeler: Algorithms for Optimization, The MIT Press, ISBN 978-0-26203942-0, (2019).
  • Vladislav Bukshtynov: Optimization: Success in Practice, CRC Press (Taylor & Francis), ISBN 978-1-03222947-8, (2023) .
  • Rosario Toscano: Solving Optimization Problems with the Heuristic Kalman Algorithm: New Stochastic Methods, Springer, ISBN 978-3-031-52458-5 (2024).
  • Immanuel M. Bomze, Tibor Csendes, Reiner Horst and Panos M. Pardalos: Developments in Global Optimization, Kluwer Academic, ISBN 978-1-4419-4768-0 (2010).
[edit]
从小一起长大的姐妹叫什么 肺部不好有什么症状 心跳过缓是什么原因造成的 坚信的意思是什么 白热化阶段是什么意思
刺激是什么意思 郑板桥爱画什么 自由基是什么东西 经常挖鼻孔有什么危害 ca125是查什么的
素颜霜是什么 壁虎吃什么食物 豆乳是什么 社恐到底在害怕什么 摩羯属于什么象星座
促排药什么时候开始吃 跳蚤长什么样子图片 牙虫长什么样子 发烧应该挂什么科 闪光点是什么意思
男生射精是什么感觉qingzhougame.com 5羟色胺是什么mmeoe.com 犹豫的反义词是什么chuanglingweilai.com 区级以上医院是什么意思hcv7jop7ns4r.cn 腰间盘膨出吃什么药效果好hcv7jop9ns8r.cn
ber什么意思imcecn.com 湿肺是什么意思hcv8jop5ns2r.cn nsfw是什么意思hcv8jop0ns5r.cn 手上的月牙代表什么意思hcv9jop6ns6r.cn 生理期可以吃什么水果hcv7jop9ns3r.cn
生日当天忌穿什么颜色xianpinbao.com cpi指数是什么意思hcv9jop8ns3r.cn 食管憩室是什么病hcv8jop2ns1r.cn 韩红和张一山什么关系hcv7jop9ns9r.cn 梅毒阳性是什么意思hcv8jop0ns9r.cn
更年期吃什么hcv8jop1ns6r.cn itp是什么病的简称hcv8jop2ns6r.cn 刚怀孕吃什么对胎儿好hcv8jop6ns9r.cn 孕妇头晕是什么原因tiangongnft.com 拍脑部ct挂什么科hcv9jop3ns6r.cn
百度