three-level return system

Three sets of common silicon controlled single return circuit control system was replaced by an intelligent temperature control instrument which gives good solutions to temperature control hysteresis and disturbance between two sys-tems in the synthesis of O-cresol.

用一台智能控温仪代替三套常规可控硅单回路控制系统，解决了化工试验研究中大滞后系统的控温问题和系统之间的相互扰动问题。

Using the Buy-and-hold abnormal return, Cumulative abnormal returns and Fama-French three-factor model as three indicators constant, by comparing the approval system and approval system under the IPO pricing efficiency, to illustrate the affection of the Stock Offering System reform on the efficiency of IPO pricing.

采用了买入持有超额收益、累计超额收益和Fama-French三因素模型的常数项三个指标，通过对比审批制和核准制下的新股发行定价效率，来说明发行制度改革对IPO定价效率的作用。

Using Three-way Return of Cartridge Valve in Hydraulic System of 25T External-Pilot Casting Machine

插装阀三通回路在25T外导式铸造机液压系统中的设计应用

Volleyball match, a return of service attack is organized after the first attack, an attack system, including return of serve, the second mass distribution of the three links of the ball and Spike.

排球比赛中，一攻是指接发球后所组织的第一次进攻，一攻系统包括接发球，二传分配球和进攻扣球三个环节。