Nanjing, China
Nanjing, China

Hohai University is a research university in Nanjing, China under the direct jurisdiction of the Ministry of Education of China. From 1958 to 2000 it was administered by the Ministry of Water Resources.The university's main focus is the research and study of water resources, and it primarily educates engineering subjects, with coordinated development of engineering, science, economics, management, arts and law. It is part of Project 211 and has set up a graduate school. Wikipedia.

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Patent
Hohai University | Date: 2015-08-05

A traffic data stream aggregate query method and system includes the steps of acquiring spatial-temporal information of a mobile object to generate a traffic data stream, dividing data space into cells, grouping adjacent cells with similar frequency into few buckets, calculating Kalman gains of the buckets based on frequencies of the buckets, and indexing the buckets using a binary partition tree to form a BPT index of the current timestamp, and serializing the BPT after the end of the current timestamp to form a historical index; and performing aggregate query, wherein an optimum estimation value of the bucket frequency is utilized to replace for calculating when the frequency of the bucket changes a lot. The system includes: an information collection module, a data processing module, an index processing module, an application service module and an index storage module.


The present invention discloses a method for uniformly coating metal nanoparticles without a carbon impurity on an oxide ceramic powder surface, which includes the steps of putting grinded and mixed a metal organic material and oxide ceramic powder into a rotational reaction chamber, then bubbling oxidizing gas under a rotational and heating condition to oxidize the metal organic material into a metal oxide, and finally bubbling reducing gas to reduce the metal oxide into nanoparticles in a metallic state, so as to implement the uniform coating of the nanoparticles in the metallic state, and avoid coarsening and growing problems of nanoparticles led by a long-term coating reaction under a high temperature. The present invention has a simple method and a short preparation period, and the metal nanoparticles prepared are uniformly dispersed and have wide application prospects in multiple fields like catalytic materials and conductive ceramics.


A facility secondary NO_(3)^( )salinized soil modifier and a modification method are disclosed. The present invention involves the preparation processes of two biological soil modifiers A and B and application methods thereof, which are specifically described as follows: (1) soil modifier A.: solid, obtained by microbial fermentation with straw powder and rice bran and the like as raw materials. C/N between 30-50, applied by uniformly mixing at 1-1.4% by mass with facility ploughing soil, co-culturing at 35-50 C. for 5-7 days, and then returning to fields; and (2) soil modifier B: liquid, subjected to salt tolerance acclimation to have effective microbial populations, and used in the crop growth period. Based on the microbial techniques, the present invention can improve soil structureness, enhance microbial activity and promote biological immobilization on inorganic nitrogen in soils, significantly increasing the facility cultivation crop yield, and improving the product quality.


Patent
Hohai University | Date: 2017-06-21

The present invention discloses an electromagnetic multiaxial fatigue testing machine, which includes a test piece fixing platform and an electromagnet loading mechanism arranged on a frame, wherein the electromagnet loading mechanism includes a first loading device for bend loading, and a second loading device for axial and torsional loading. The first loading device includes a first permanent magnet and a first electromagnet with a direction of a magnetic force generated therebetween is orthogonal to an axial direction of a test piece; the second loading device includes a second permanent magnet and a second electromagnet mounted on a swinging pair with a direction of a magnetic force generated therebetween is parallel to the axial direction of the test piece. An electromagnet principle is adopted in the invention for loading, which does not cause mechanical frictions, and different loading modes can be selected according to the actual stress requirements to conduct a uniaxial or multiaxial fatigue test on the test piece, so that the testing efficiency is improved, and the testing noise and testing cost are reduced.


Patent
Hohai University | Date: 2016-11-21

A device for purifying first-stage drainage effluents from dry croplands, the device including: a) a plastic corrugated pipe including an upright segment and a horizontal segment, the upright segment comprising plastic mesh openings; b) a steel wire mesh box filled with stuffing pellets including biological carriers; and an inspection cover. The plastic mesh openings are disposed at one end of the upright segment, the other end of the upright segment is connected to one end of the horizontal segment, and the other end of the horizontal segment is connected to the steel wire mesh box. The upper surface of the upright segment of the plastic corrugated pipe is lower than the upper surface of the field ditch, and the lower edge of the plastic mesh openings is higher than the bottom surface of the field ditch.


A tungsten carbide-cubic boron nitride composite material and preparation method thereof mainly includes WC and cBN, wherein the WC powder is coated with Co nano-layer and the cBN powder is coated with SiO_(2 )nano-layer, and hardness and toughness of the composition material can be improved by coating. The method for preparing a tungsten carbide-cubic boron nitride composite material adopts chemical vapor deposition method and high temperature sintering method. First nano-layers were coated on the surface of WC and cBN, and then the bulk materials can be obtained via high-temperature sintering.


The invention discloses a segment-assembled type pier column member with a steel-concrete composite structure, which includes a reinforcement tube embedded in a pile cap, wherein the reinforcement tube is connected with a bottom of a lower segment of a hollow steel tube pier and is poured with concrete, and pier columns in upper and lower segments are reinforced by means of segment connecting and being embedded with local reinforcing meshes. A steel cross beam is connected with an upper segment of the hollow steel tube pier in an assembled way. A pre-stressed tensioning duct is reserved between the steel cross beam and the pier column in the upper segment. According to the present invention, a construction period and construction difficulty are reduced, a construction progress is accelerated, the connecting method is safe and reliable, and is convenient to control by adopting an assembled construction method; meanwhile, good concrete compression performance and good steel tensile property are sufficiently utilized, so that the whole member is economic and convenient, is simple and fast to construct, and has a good application prospect.


A heat source-free fiber positioning and orienting system for seepage of submerged or partially submerged structures and monitoring method thereof includes a plurality of seepage monitoring devices connected through rotary supports. The seepage monitoring devices include first seepage monitoring units symmetrically distributed on the front and back and second seepage monitoring units symmetrically distributed on left and right. Seepage, monitoring fibers are distributed in the first seepage monitoring units and the second seepage monitoring units, and the seepage conditions of the submerged or partially submerged structures are monitored through the seepage monitoring fibers. The heat source-free fiber positioning and orienting system for the seepage of submerged or partially submerged structures has the characteristics of no heating, distribution manner, multiple orientations and synchronicity or the like.


The present invention relates to a distributed sensing optical fiber performance multi-objective multi-degree-of-freedom static and dynamic test integrated platform and a test method. In a distributed sensing optical fiber multi-objective multi-degree-of-freedom static and dynamic test device, an optical fiber multi-degree-of-freedom fixing system is sequentially connected with an artificial loading and unloading device and an oil pressure control loading and unloading device, and an optical fiber under test is connected with the optical fiber multi-degree-of-freedom fixing system and a distributed optical fiber Brillouin frequency shift acquisition system; and test on performance of optical fiber is achieved by controlling devices in the optical fiber multi-degree-of-freedom fixing system. All parts of the test platform can be freely dissembled and assembled, and in order to complete different test requirements, a multi-objective test platform is set up, which provides large secondary development space for possible test and exploration; the device of the present invention has a large number of advantages such as a simple structure, a low cost, convenient operation, less disturbance, many test classes, strong adaptability, stable performance and convenient loading and unloading (Fig. 1).


The present invention discloses a heat source-free fiber positioning and orienting system for seepage of submerged or partially submerged structures and monitoring method thereof, which includes a plurality of seepage monitoring devices connected through rotary supports, wherein the seepage monitoring devices include first seepage monitoring units symmetrically distributed on the front and back and second seepage monitoring units symmetrically distributed on left and right, seepage monitoring fibers are distributed in the first seepage monitoring units and the second seepage monitoring units, and the seepage conditions of the submerged or partially submerged structures are monitored through the seepage monitoring fibers. The heat source-free fiber positioning and orienting system for the seepage of submerged or partially submerged structures according to the present invention has the characteristics of no heating, distribution manner, multiple orientations and synchronicity or the like, and has prominent advantages on such aspects like reducing the monitoring cost, improving the monitoring precision and engineering practicability or the like; and through flexibly disposing the seepage monitoring device in the submerged or partially-submerged structures, the seepage position and direction are obtained through comparison of calibrated fibers and the seepage monitoring fibers; therefore, the monitoring method of the present invention is simple to operate and has accurate results.

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