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1 Markets I: The Ecosystem and Exchange-Traded Markets市场在线 2 Markets II: Rates, FX and Credit市场在线 3 Markets III: Commodities, Energy and Crypto市场在线 4 Quantitative Methods方法在线 5 Derivatives and Volatility衍生品在线 6 Rates, Credit, XVA and Risk利率、信用与风险在线 7 Research Craft: Predictors, Backtests, Measurement, Portfolios研究在线 8 Strategies I: Equities and Futures策略在线 9 Strategies II: Volatility, Relative Value, Macro and the Bank Desks策略在线 10 Microstructure and Execution交易执行在线 11 Market Making and High-Frequency Trading做市在线 12 Machine Learning for Markets机器学习在线 13 Low-Latency Software技术在线 14 Networks, Hardware and Trading Infrastructure技术在线 15 Research, Data and Risk Platforms技术在线 16 The Desk and the Firm公司运营在线 17 The Industry: Firms, Roles and Careers职业发展在线 18 Interviews I: Maths, Probability and Speed职业发展在线 19 Interviews II: Markets, Trading Games and the Final Round职业发展在线 20 Interviews III: Code职业发展在线

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Physics · 术语表

什么是 Control volume; open system？

Definition 5.1 University Physics — Year 2 · 第 5 章 — Momentum and Energy Balances in Flows

A control volume (or control surface) is a fixed region of space $\Sigma$ through which fluid flows; the fluid inside it at any instant is an open system, which exchanges mass with the outside through the inlets and outlets of $\Sigma$ . The closed system to which Newton’s laws apply is the fluid that is inside $\Sigma$ at time $t$ , followed to $t + \dd t$ : it then occupies $\Sigma$ minus what has left plus what has entered.

Left: a control volume in a steady flow — the momentum leaving through S_2 minus that entering through S_1 equals the sum of the external forces on the fluid inside, pressure forces on the two sections included. Right: a jet stopped by a wall pushes it with D_mv; a jet turned back by a Pelton bucket moving at u pushes with up to 2D_m(v - u). — Left: a control volume in a steady flow — the momentum leaving through $S_2$ minus that entering through $S_1$ equals the sum of the external forces on the fluid inside, pressure forces on the two sections included. Right: a jet stopped by a wall pushes it with $D_mv$ ; a jet turned back by a Pelton bucket moving at $u$ pushes with up to $2D_m(v - u)$ .

Left: a control volume in a steady flow — the momentum leaving through S_2 minus that entering through S_1 equals the sum of the external forces on the fluid inside, pressure forces on the two sections included. Right: a jet stopped by a wall pushes it with D_mv; a jet turned back by a Pelton bucket moving at u pushes with up to 2D_m(v - u). — Left: a control volume in a steady flow — the momentum leaving through $S_2$ minus that entering through $S_1$ equals the sum of the external forces on the fluid inside, pressure forces on the two sections included. Right: a jet stopped by a wall pushes it with $D_mv$ ; a jet turned back by a Pelton bucket moving at $u$ pushes with up to $2D_m(v - u)$ .

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