China University of Mining and Technology

Ruirui Li

Xiumei Liu

Jie He

Beibei Li

Wei Li

Jingjing Wang

Lian Zhu Liu

Yu Chen

Xiang Wu

Jingyuan Wang

Huanhuan Wang

Yaoda Yue

The invention discloses privacy protection query language PQL and system thereof, comprising PQL statement and system, the system comprises parsing module, query module and noise-injection module; the parsing module comprises lexical analyzer and syntactic analyzer; user inputs PQL statement according to predetermined semantic and syntactic rules, after parsing module receives the PQL statement, lexical analyzer performs error checks on the PQL statement, correct results are sent to syntactic analyzer; the syntactic analyzer performs grammatical and semantic checks on PQL statement, generates a mapping table and a parameter table with correct results; after receiving mapping table, the query module encapsulates the same into SQL statement, and verifies the encapsulated SQL statement; the noise-injection module obtains final query results of the query module, calculates noise injection sensitivity according to parameter table; the invention ensures the data privacy security and satisfies that the injected noise does not affect data availability.

Method to use privacy protection query language PQL to improve the security of shared date

The present invention discloses a gas-powder separation three-phase jet flow fire monitor system, including a gas-powder separation three-phase fire monitor head, a filter, a nitrogen pressurization apparatus and a dry powder tank. The dry powder tank is connected to a gas-powder mixture inlet pipe of the gas-powder separation three-phase fire monitor head through a pipeline. A nitrogen outlet pipe of the gas-powder separation three-phase fire monitor head is connected with one end of the nitrogen pressurization apparatus through the filter. The other end of the nitrogen pressurization apparatus is connected with the dry powder tank. The present invention is simple in structure and convenient to use. A cyclone separation apparatus of a dry powder pipeline of the fire monitor may separate nitrogen from conveyed ultrafine dry powder to enable the ultrafine dry powder to be fully mixed with a water-based fire extinguishing agent, thereby reducing an atomization degree of jet flow and enlarging a range of the fire monitor. In addition, the separated nitrogen enters the dry powder tank for recycling after being pressurized by the pressurization apparatus, thereby reducing the fire extinguishing cost.

Gas-powder separation three-phase jet flow fire monitor system

Disclosed in the present invention is a double-spring and high-precision hysteretic pressure control valve, including an upper valve body, a lower valve body, a double-spring pressure adjustment valve, a spring energy storage linkage mechanism, and a main valve. The double-spring pressure adjustment valve includes a rough adjustment stud, a rough adjustment spring, a fine adjustment stud, a fine adjustment spring, a spring guide sleeve, and a pressure adjustment valve spool. The spring energy storage linkage mechanism includes a guide block, a valve spool control linkage, a tension spring, and a tension spring shift lever and a tension spring sliding hook. The valve spool control linkage is connected to the guide block at one end, and connected to a main valve spool drive rod via a pin at the other end. The tension spring sliding hook is mounted on the guide block, and one end of the shift lever is placed below the tension spring sliding hook so as to drive the tension spring sliding hook to move upwards, thereby controlling the state of the tension spring and enabling energy storage of the spring. The spring energy storage linkage mechanism make the valve spool to open and close momentarily at the right portion. The double-spring and high-precision hysteretic pressure control valve according to the present invention has a low cost, and can provide precise control of opening and closing pressures for the pressure control valve and control of both states of opening and closing for the main valve.

Double-spring and high-precision hysteretic pressure control valve

Growing community of inventors

Jiangsu, China

Ruirui Li