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| | [[Image:Adoption SFD1.png|centre|''新产品采用''模型的存量-流量|frame]] | | [[Image:Adoption SFD1.png|centre|''新产品采用''模型的存量-流量|frame]] |
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| − | ===方程式 Equations=== | + | ===方程式=== |
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| − | The real power of system dynamics is utilised through simulation. Although it is possible to perform the modeling in a [[spreadsheet]], there are a [[Comparison of system dynamics software|variety of software]] packages that have been optimised for this.
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| − | The real power of system dynamics is utilised through simulation. Although it is possible to perform the modeling in a spreadsheet, there are a variety of software packages that have been optimised for this.
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| | 通过仿真实现了系统动力学的真正威力。尽管在电子表格中执行建模是可能的，但是已经为此优化了各种软件包。 | | 通过仿真实现了系统动力学的真正威力。尽管在电子表格中执行建模是可能的，但是已经为此优化了各种软件包。 |
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| − | The steps involved in a simulation are:
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| − | The steps involved in a simulation are:
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| | 模拟涉及的步骤如下: | | 模拟涉及的步骤如下: |
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| | + | *定义问题边界 |
| | + | *确定改变这些存量水平的最重要的存量和流量 |
| | + | *确定影响信息流的信息来源 |
| | + | *确定主要反馈回路 |
| | + | *绘制一个因果循环图，将存量、流量和信息来源联系起来 |
| | + | *写出确定流量的方程式 |
| | + | *估计参数和初始条件。这些可以使用统计方法、专家意见、市场研究数据或其他相关信息来源进行估计。 |
| | + | <ref name="Sterman2001CMR">{{cite journal |last=Sterman |first=John D. |year=2001 |title=System dynamics modeling: Tools for learning in a complex world |journal=California Management Review|volume=43 |issue=4 |pages=8–25|doi=10.2307/41166098 |jstor=41166098 }}</ref> |
| | + | * 对模型进行仿真分析。 |
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| − | *Define the problem boundary 定义问题边界
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| − | *Identify the most important stocks and flows that change these stock levels 确定改变这些存量水平的最重要的存量和流量
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| − | *Identify sources of information that impact the flows 确定影响信息流的信息来源
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| − | *Identify the main feedback loops 确定主要反馈回路
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| − | *Draw a causal loop diagram that links the stocks, flows and sources of information 绘制一个因果循环图，将存量、流量和信息来源联系起来
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| − | *Write the equations that determine the flows 写出确定流量的方程式
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| − | *Estimate the parameters and initial conditions. These can be estimated using statistical methods, expert opinion, market research data or other relevant sources of information. 估计参数和初始条件。这些可以使用统计方法、专家意见、市场研究数据或其他相关信息来源进行估计。
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| − | <ref name="Sterman2001CMR">{{cite journal |last=Sterman |first=John D. |year=2001 |title=System dynamics modeling: Tools for learning in a complex world 系统动力学建模：在复杂世界中学习的工具 |journal=California Management Review 加州管理评论 |volume=43 |issue=4 |pages=8–25|doi=10.2307/41166098 |jstor=41166098 }}</ref>
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| − | *Simulate the model and analyse results. 对模型进行仿真分析。
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| − | In this example, the equations that change the two stocks via the flow are:
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| − | In this example, the equations that change the two stocks via the flow are:
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| | 在这个例子中，通过流量改变两种股票的方程是: | | 在这个例子中，通过流量改变两种股票的方程是: |
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| | + | <math>\ \mbox{Potential adopters} = \int_{0} ^{t} \mbox{-New adopters }\,dt </math> |
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| − | | + | <math> \ \mbox{Adopters} = \int_{0} ^{t} \mbox{New adopters }\,dt </math> |
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| − | <math> \ \mbox{Potential adopters} = \int_{0} ^{t} \mbox{-New adopters }\,dt </math>
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| − | <math> \ \mbox{Potential adopters} = \int_{0} ^{t} \mbox{-New adopters }\,dt </math>
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| − | 数学{潜在采纳者} int {0}{ t } mbox {-New adopters } ，dt / math
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| − | <!-- I don't want to mark up this great contribution, but shouldn't this be something like potential adopters at t(0) - sum(new adopters at t(i))? Yes -->
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| − | <!-- I don't want to mark up this great contribution, but shouldn't this be something like potential adopters at t(0) - sum(new adopters at t(i))? Yes -->
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| − | <！ -- 我不想标记这个巨大的贡献，但是这难道不应该像 t (0)-sum (t (i))的潜在采用者那样吗？是的
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| − | <math> \ \mbox{Adopters} = \int_{0} ^{t} \mbox{New adopters }\,dt </math>
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| − | <math> \ \mbox{Adopters} = \int_{0} ^{t} \mbox{New adopters }\,dt </math>
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| − | 数学{ Adopters } int {0}{ t } mbox { New Adopters } ，dt / math
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| | ===离散时间方程 Equations in discrete time=== | | ===离散时间方程 Equations in discrete time=== |