Precast Pavement Smoothness Control Method

2014 ◽  
Vol 587-589 ◽  
pp. 1071-1074 ◽  
Author(s):  
Peng Peng ◽  
De Fen Wu ◽  
Bo Tian ◽  
Kai Min Niu
Keyword(s):  
Control Method ◽  
Control Measure ◽  
Road Maintenance ◽  
Precision Control ◽  
Service Effectiveness ◽  
Base Course

In the course of road maintenance, importance has been gradually attached by administrative authorities to precast pavement for its advantages like quickness, endurance and eco-friendliness. To ensure the smoothness of precast pavement, analyses and researches were done in terms of, say, precast pavement slab precision control, base course treatment, fabricated pavement slab leveling and treatment of joint faulting, and a control measure to ensure and improve the smoothness of precast pavement is suggested with consideration given to its service effectiveness in actual projects.

A novel synchronous coupling precision control method for electronic gearbox

2016 ◽  
pp. 859-866
Author(s):  
L.L. Wu ◽  
J. Han ◽  
X.Q. Tian ◽  
L. Xia
Keyword(s):  
Control Method ◽  
Precision Control

scholarly journals Examination of Acephate Absorption, Transport, Metabolism, and Accumulation in Maize After Root Irrigation for Spodoptera Frugiperda Control

2021 ◽  
Author(s):  
jiyingzi Wu ◽  
xianjia Li ◽  
ruiquan Hou ◽  
kunyu Zhao ◽  
yongqin Wang ◽  
...  
Keyword(s):  
Pest Control ◽  
Spodoptera Frugiperda ◽  
Control Method ◽  
Control Measure ◽  
Fall Armyworm ◽  
Extended Period ◽  
Field Trials ◽  
Pesticide Use ◽  
Control Efficacy ◽  
Maize Plants

Abstract BACKGROUND: Since the invasion of the fall armyworm moth (Spodoptera frugiperda) in China in January 2019, damage to maize crops has gradually intensified, and chemical control has become the main control measure. This study aimed to examine methods of effective pest control while monitoring the environmental impact of pesticide use. The effectiveness of S. frugiperda pest control by foliar spraying and root irrigation of maize plants with acephate was determined, and the absorption, distribution, and dissipation of acephate and methamidophos by maize were studied.RESULTS: Field trials showed that acephate treatment at 6000 g.a.i ha-1 was the most effective for controlling S. frugiperda. Acephate and methamidophos were absorbed from the roots, transported upward, and concentrated in the leaves, particularly new leaves. The terminal residues of acephate and methamidophos in maize grains were below detectable levels at 60 days after treatment.CONCLUSIONS: The results demonstrate that acephate treatment via root irrigation can more effectively control the infestation of S. frugiperda in maize than acephate treatment via foliar spraying. The translocation and distribution of acephate and methamidophos by root irrigation were more uniform, and the holding efficiency was higher than those in foliar spraying, suggesting an extended period of control efficacy. This pest control method could be utilized to reduce pesticide residues while safely and efficiently controlling S. frugiperda infestation.

High-precision control method for the satellite with large rotating components

2019 ◽  
Vol 92 ◽  
pp. 91-98 ◽  
Author(s):  
Feng Wang ◽  
Chi Wang ◽  
Xue-qin Chen ◽  
Cheng-fei Yue ◽  
Yi-fei Xie ◽  
...  
Keyword(s):  
High Precision ◽  
Control Method ◽  
Precision Control

Precision Control of Micromechanical Automatic Manufacturing Based on Nanotechnology

2020 ◽  
Vol 12 (12) ◽  
pp. 1368-1377
Author(s):  
Ailian Li
Keyword(s):  
Contact Area ◽  
Control Method ◽  
Random Sequence ◽  
Control Flow ◽  
Current Loop ◽  
Curvature Radius ◽  
Element Analysis ◽  
Precision Control ◽  
Micro Machine ◽  
Automatic Manufacturing

Segment precision affects the accuracy level of micro machine manufacturing, only for the linear change is not big, more straight segment control, easy to cause dimensional deviation, so a precision control method of micro machine automatic manufacturing based on nanotechnology is proposed. The white noise is selected as random sequence to eliminate the concentrated trend and high frequency components in the input and output data. The precision control parameters of micromechanical automatic manufacturing are adjusted by setting the current loop, speed loop and position loop. According to the setting results, the contact area of micromechanical automation manufacturing is established in the coordinate system o-xy, and the equivalent curvature radius of the contact surface is calculated. Through coordinate transformation, the pressure distribution in the circular contact area is obtained, and the precision control area model of micromanical automation manufacturing is established. According to the model and the finite element analysis method, the control flow is designed to realize the precision control of the automatic manufacturing of micromachines. The experimental results show that the design method can reduce the precision control error of the automatic manufacturing of micromachines and improve the construction level of micromachines.

Quality Control of CSG with P-Wave Speed Measurement

2014 ◽  
Vol 1049-1050 ◽  
pp. 497-504 ◽  
Author(s):  
Xiao Bin Lu ◽  
Jin Sheng Jia ◽  
Feng Ling Ma ◽  
Wei Feng ◽  
Li Juan Meng
Keyword(s):  
Quality Control ◽  
Wave Speed ◽  
Control Method ◽  
Control Measure ◽  
P Wave ◽  
Experimental Program ◽  
Compression Tests ◽  
Cemented Sand ◽  
Speed Measurement ◽  
Sand And Gravel

This paper first introduces the basic concept of the CSG (cemented sand and gravel) dam construction. It then puts forward a new quality control method by inspecting the in-situ P-wave speed of CSG as an alternative to the conventional specimen compression tests. Through an extensive experimental program, it is found that there is a good correlation between the compressive strength and P-wave speed of CSG, which makes the P-wave speed measurement potentially an effective and efficient quality control measure to evaluate the CSG strength on site.

scholarly journals CONDITION ASSESSMENT OF LOWER ROADWAY LAYERS FOR PAVEMENT MANAGEMENT SYSTEMS

2015 ◽  
Vol 22 (3) ◽  
pp. 311-321 ◽  
Author(s):  
Andrzej POŻARYCKI
Keyword(s):  
Lower Layer ◽  
Technical Condition ◽  
Pavement Management ◽  
Road Maintenance ◽  
Pavement Management System ◽  
Practical Applications ◽  
Road Pavement ◽  
Pavement Management Systems ◽  
Base Course ◽  
Falling Weight

The process of selecting road maintenance technologies for the Pavement Management System (PMS) can use road pavement moduli of deformation as the substantiating information. Assessment criteria based on either pavement or base course moduli of deformation have strong empirical underpinning, since the stiff plate bearing testing (SPBT) is commonly used worldwide. This paper discusses potential practical applications of plate bearing test numerical simula­tion based on Falling Weight Deflectometer (FWD) deflection data, and theoretical model based on flexible pavement. It was proven that including a pavement model with stress dependency, the simulated second load-displacement curves meet reliably plate bearing in-situ test conditions for different layers of either subgrade or base courses of road pave­ment. This methodology is feasible by classifying technical condition of each lower layer of road pavement against requirements towards new pavements.

scholarly journals Fungal leaf spot diseases of mango (Mangifera indica L.) in Southeastern Nigeria and biological control with Bacillus subtilis

2011 ◽  
Vol 39 (No. 2) ◽  
pp. 70-77 ◽  
Author(s):  
R.N. Okigbo ◽  
M.I. Osuinde
Keyword(s):  
Biological Control ◽  
Bacillus Subtilis ◽  
Leaf Spot ◽  
Control Method ◽  
Control Measure ◽  
Mangifera Indica ◽  
Pathogenic Fungi ◽  
Southeastern Nigeria ◽  
Plant Materials

The incidence of fungal leaf spot diseases on mango (Mangifera indica) in Southeastern Nigeria and application of a biological control measure was investigated. The survey proved that the incidence of leaf spot diseases was greatest in Umuahia (72%) followed by Okigwe and Ojoto, with a peak at the beginning of the rainy season (February–March). Three pathogenic fungi, Pestalotiopsis mangiferae, Botryodiplodia theobromae and Macrophoma mangiferae, were isolated from leaf spots. Other fungi, Fusariella spp., which are well known saprophytes of dead plant materials, and the fungus Meliola sp., were also isolated from diseased leaves. Pathogenicity tests showed that P. mangiferae, B. theobromae and M. mangiferae were the causal agents of the fungal leaf spot diseases. Symptoms developed 5 weeks after inoculation of healthy leaves. Bacillus subtilis NCIB 3610, isolated from soil under a mango tree, inhibited P. mangiferae, B. theobromae and M. mangiferae by 57%, 61% and 58% respectively on agar plates. Also, in in vivo experiments the symptoms were considerably reduced in the field by the application of the antagonist. The importance of the biological control method for rural mango farmers is emphasised.  

Digital Control System Design of Carving Machine Based on DSP

2012 ◽  
Vol 503-504 ◽  
pp. 1343-1346
Author(s):  
Zhong Jin Ni ◽  
Liang Fang ◽  
Mao Jun Chen
Keyword(s):  
Control System ◽  
High Precision ◽  
Digital Control ◽  
Control Method ◽  
Control System Design ◽  
Digital Control System ◽  
Servo Motor ◽  
System Operation ◽  
Precision Control ◽  
Motor Controller

A digital control system of high-precision carving machine is presented in this paper. According to the requirements of high-precision caving machine, a servo motor controller based on the field orientated control (FOC) strategy is applied. Thus the high-precision control system base on DSP of electronic carving machine is realized. The results of system operation are shown that the control system and the servo motor controllers can run steadily and precisely. The system also represent that inter - connected controls parameters of this system were correct and valid, the control method was proper and effective

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