Elliptical encirclement control capable of reinforcing performances for UAVs around a dynamic target

Most researches associated with target encircling control are focused on moving along a circular orbit under an ideal environment free from external disturbances.However,elliptical encirclement with a time-varying observation radius,may permit a more flexible and high-efficacy enclosing solution,whilst the non-orthogonal property between axial and tangential speed components,non-ignorable environmental perturbations,and strict assignment requirements empower elliptical encircling control to be more challenging,and the relevant investigations are still open.Following this line,an appointed-time elliptical encircling control rule capable of reinforcing circumnavigation performances is developed to enable Unmanned Aerial Vehicles(UAVs)to move along a specified elliptical path within a predetermined reaching time.The remarkable merits of the designed strategy are that the relative distance controlling error can be guaranteed to evolve within specified regions with a designer-specified convergence behavior.Meanwhile,wind perturbations can be online counteracted based on an unknown system dynamics estimator(USDE)with only one regulating parameter and high computational efficiency.Lyapunov tool demonstrates that all involved error variables are ultimately limited,and simulations are implemented to confirm the usability of the suggested control algorithm.

Field implementation of enzyme-induced carbonate precipitation technology for reinforcing a bedding layer beneath an underground cable duct

A suitable bearing capacity of foundation is critical for the safety of civil structures.Sometimes foundation reinforcement is necessary and an effective and environmentally friendly method would be the preferred choice.In this study,the potential application of enzyme-induced carbonate precipitation(EICP)was investigated for reinforcing a 0.6 m bedding layer on top of clay to improve the bearing capacity of the foundation underneath an underground cable duct.Laboratory experiments were conducted to determine the optimal operational parameters for the extraction of crude urease liquid and optimal grain size range of sea sands to be used to construct the bedding layer.Field tests were planned based on orthogonal experimental design to study the factors that would significantly affect the biocementation effect on site.The dynamic deformation modulus,calcium carbonate content and longterm ground stress variations were used to evaluate the bio-cementation effect and the long-term performance of the EICP-treated bedding layer.The laboratory test results showed that the optimal duration for the extraction of crude urease liquid is 1 h and the optimal usage of soybean husk powder in urease extraction solution is 100 g/L.The calcium carbonate production rate decreases significantly when the concentration of cementation solution exceeds 0.5 mol/L.The results of site trial showed that the number of EICP treatments has the most significant impact on the effectiveness of EICP treatment and the highest dynamic deformation modulus(Evd)of EICP-treated bedding layer reached 50.55 MPa.The area with better bio-cementation effect was found to take higher ground stress which validates that the EICP treatment could improve the bearing capacity of foundation by reinforcing the bedding layer.The field trial described and the analysis introduced in this paper can provide a practical basis for applying EICP technology to the reinforcement of bedding layer in poor ground conditions.

Assessment of Deviation in Quality of Steel Reinforcing Bars Used in Some Building Sites in Cameroon

The present work evaluated the deviations in the quality of steel reinforcing bars in terms of markings, diameter, yield strength and ductility in order to facilitate the drawing up of a yield strength value for the Cameroon National Annex to Eurocode 2. The methodology of the work started with the collection of steel samples from various active building project sites in four different towns viz: Bamenda, Douala, Maroua and Yaoundé and testing their tensile strength and elongation using a Universal Testing Machine and also carrying out the bending test. Results show that bars without marked manufacturer’s name fell all the tests. Other results show that 52% of all the steel had yield stresses below 400 Mpa and the highest deviation in the yield strengths was 22.50%. The study recommends that properly marked grade 500 steel bars should be adopted in the Cameroon national annex to Eurocode 2.

基于Reinforcing Steel本构的高强钢筋混凝土柱纤维模型研究

为了研究HTRB630E级高强钢筋的基本力学参数和疲劳性能,本文进行了应变等幅低周疲劳性能试验,并将试验结果与HRB400级钢筋的结果进行了对比分析。首先,基于应变等幅低周疲劳试验数据点,对OpenSees程序中Reinforcing Steel材料本构的疲劳参数C f、C d和α进行拟合,然后采用拟合的Reinforcing Steel材料本构疲劳三参数,基于OpenSees软件对钢筋混凝土柱有限元纤维模型进行数值模拟,最后将数值结果与试验柱结果对比分析。结果表明:拟合的疲劳三参数对有限元纤维模型有优化效果,为配置HTRB630E级高强钢筋混凝土结构数值纤维模型提供参考。

Simulation Study on Reinforcing Overburden to Prevent and Cure the Rupture of Shaft Lining

For preventing and curing the rupture disaster of shaft lining effectively, according to the additional force theory of shaft lining fracture, more than forty tests were carried out on the large scale test rig on the basis of simulating theory. The influence of the position of aquifer, the reinforcing scope of aquifer, reinforcing distance and the strength of grouting cemented mixture on the value and variation law of the axial additional force on shaft lining is studied. The relationships between the reinforcing parameters and the axial additional force on shaft lining are obtained, which provides the theoretic foundation and construction design parameters for the method of reinforcing strata by grouting to prevent and cure tbe rupture disaster of shart lining.

Immediate effects of scalp acupuncture with twirling reinforcing manipulation on hemiplegia following acute ischemic stroke: a hidden association study

Data mining has the potential to provide information for improving clinical acupuncture strategies by uncovering hidden rules between acupuncture manipulation and therapeutic effects in a data set. In this study, we performed acupuncture on 30 patients with hemiplegia due to acute ischemic stroke. All participants were pre-screened to ensure that they exhibited immediate responses to acupuncture. We used a twirling reinforcing acupuncture manipulation at the specific lines between the bilateral Baihui（GV20） and Taiyang（EX-HN5）. We collected neurologic deficit score, simplified Fugl-Meyer assessment score, muscle strength of the proximal and distal hemiplegic limbs, ratio of the maximal H-reflex to the maximal M-wave（Hmax/Mmax）, muscle tension at baseline and immediately after treatment, and the syndromes of traditional Chinese medicine at baseline. We then conducted data mining using an association algorithm and an artificial neural network backpropagation algorithm. We found that the twirling reinforcing manipulation had no obvious therapeutic difference in traditional Chinese medicine syndromes of ＂Deficiency and Excess＂. The change in the muscle strength of the upper distal and lower proximal limbs was one of the main factors affecting the immediate change in Fugl-Meyer scores. Additionally, we found a positive correlation between the muscle tension change of the upper limb and Hmax/Mmax immediate change, and both positive and negative correlations existed between the muscle tension change of the lower limb and immediate Hmax/Mmax change. Additionally, when the difference value of muscle tension for the upper and lower limbs was 〉 0 or 〈 0, the difference value of Hmax/Mmax was correspondingly positive or negative, indicating the scalp acupuncture has a bidirectional effect on muscle tension in hemiplegic limbs. Therefore, acupuncture with twirling reinforcing manipulation has distinct effects on acute ischemic stroke patients with different symptoms or stages of disease. Improved muscle tension in the upper and lower limbs, reflected by the variation in the Hmax/Mmax ratio, is crucial for recovery of motor function from hemiplegia.

Control mechanism and technique of floor heave with reinforcing solid coal side and floor corner in gob-side coal entry retaining

Floor heave is the most common convergence in gob-side entry retaining.The paper analyzes the form,process and characteristics of gob-side entry retaining with the comprehensive methods of theoretical analysis,numerical simulation and the field trial.Research results present that bending and folding floor heave is the main factor in the stage of the first panel mining;squeezing and fluidity floor heave plays a great role in the stable stage of gob-side entry retaining;the combination of the former two factors affects mainly the stage of the second mining ahead;abutment pressure is a fundamental contribution to the serious floor heave of gob-side entry retaining,and sides corners of solid coal body are key part in the case of floor heave controlling of gob-side entry retaining.Floor heave of gob-side entry retaining can be significantly controlled by reinforcing sides and corners of solid coal body,and influence rules on the floor heave of gob side entry retaining of sides supporting strength and the bottom bolt orientation in solid coal side are obtained.Research results have been successfully applied in gob-side entry retaining of G20-F23070 face haulage roadway in #2 coal mine of Pingmei Group,and the field observation shows that the proposed technique is an effective way in controlling the floor heave of gob-side entry retaining.

Reinforcing effect of calcium sulfate cement bovine bone morphogenetic protein on vertebral in the rabbit model of osteoporosis

Objective:To observe reinforcing effect of calcium sulfate cement(CSC) bovine bone morphogenetic protein(bBMP) on vertebral in the rabbit model of osteoporosis.Methods:A total of 48 New Zealand white rabbits were randomly divided into group Ⅰ(blank control group),groupⅡ(CSC injection group),group Ⅲ(CSC/bBMP injection group) and control group.White rabbit osteoporosis model was established rapidly by using castration mcthod+methylprcdnisolone candidate.After modeling,groups Ⅱ.Ⅲ were given corresponding vertebral body injection material,and 4 animals were sacrificed respectively at 24 h,6 weeks,12 weeks after vertebral plasty.Tissue pathological status,vertebral mineral density and vertebral body bone mechanical strength were observed.Results:Vertebral body structure form was normal in the groups Ⅱand Ⅲ.Trabecular bone coarsens,connection and repair were observed in micro fracture and bone defects,bone trabecular connectivity was superior to group I significantly;vertebral body compression strength in the group I was on the decline,vertebral compression strength in the groups Ⅱ and Ⅲ was on the rise,the largest vertebra.Postoperative BMC and BMD in groups Ⅱand Ⅲ were incresed,and significantly higher than group I after 6 weeks(P<0.05),BMC and BMD in group Ⅲ after 12 weeks were higher than the other three groups.Conclusion:Compound bBMP CSC has good bone induction.It can improve the three-dimensional construction effect for osteoporosis vertebral trabecula,and can significantly improve the vertebral strength,as a vertebral packing material with good application prospect.

Acupuncture with reinforcing and reducing twirling manipulation inhibits hippocampal neuronal apoptosis in spontaneously hypertensive rats

To observe the effects of different acupuncture manipulations on blood pressure and target organ damage in spontaneously hypertensive rats（SHRs）, this study used the reinforcing twirling method（1.5–2-mm depth; rotating needle clockwise for 360° and then counter clockwise for 360°, with the thumb moving heavily forward and gently backward, 60 times per minute for 1 minute, and retaining needle for 9 minutes）, the reducing twirling method（1.5–2-mm depth; rotating needle counter clockwise for 360° and then clockwise for 360°, with the thumb moving heavily backward and gently forward, 60 times per minute for 1 minute, and retaining needle for 9 minutes）, and the needle retaining method（1.5–2-mm depth and retaining the needle for 10 minutes）. Bilateral Taichong（LR3） was treated by acupuncture using different manipulations and manual stimulation. Reinforcing twirling, reducing twirling, and needle retaining resulted in a decreased number of apoptotic cells, reduced Bax m RNA and protein expression, and an increased Bcl-2/Bax ratio in the hippocampus compared with the SHR group. Among these groups, the Bcl-2/Bax protein ratio was highest in the reducing twirling group, and the Bcl-2/Bax m RNA ratio was highest in the needle retaining group. These results suggest that reinforcing twirling, reducing twirling, and needle retaining methods all improve blood pressure and prevent target organ damage by increasing the hippocampal Bcl-2/Bax ratio and inhibiting cell apoptosis in the hippocampus in SHR.

Study on mechanical principle of reinforcing sidewalls and corners of roadway to control floor heave by anchors

The movement principle of sidewalls and floor of extraction opening is analyzed, it is found that floor heave not only has something to do with the floor strata, but sidewalls. The effect of sidewall anchor and corner anchor is studied, the mechanical principle of reinforcing sidewalls and corners is put forward and applied in engineering practice.

Numerical analysis of tunnel reinforcing influences on failure process of surrounding rock under explosive stress waves

Based on mesoscopic damage mechanics, numerical code RFPA2D （dynamic edition） was developed to analyze the influence of tunnel reinforcing on failure process of surrounding rock under explosive stress waves. The results show that the propagation phenomenon of stress wave in the surrounding rock of tunnel and the failure process of surrounding rock under explosive stress waves are reproduced realistically by using numerical code RFPA2O; from the failure process of surrounding rock, the place at which surrounding rock fractures is transferred because of tunnel reinforcing, and the rockfall and collapse caused by failure of surrounding rock are restrained by tunnel reinforcing; furthermore, the absolute values of peak values of major principal stress, and the minimal principal stress and shear stress at center point of tunnel roof are reduced because of tunnel reinforcing, and the displacement at center point of runnel roof is reduced as well, consequently the stability of tunnel increases.

52 CASES OF APOPLEXY TREATED WITH SCALP ACUPUNCTURE BY THE SLOW-RAPID REINFORCING-REDUCING METHOD

85 cases of apoplexy were treated with scalp acupuncture,including 52 cases by the methodof slow-rapid reinforcing-reducing and 33 cases by the method of flat twisting.The totak ef-fective rates differed insignificantly between the 2 methods.However,in respects of im-proving the myodynamia and motile functional disturbances of the limbs,the method ofslow-rapid reinforcing-reducing was markedly superior to the method of flat twisting.

Investigation of nano-talc as a filling material and a reinforcing agent in high density polyethylene (HDPE)

An experiment of producing high density polyethylene (HDPE) nano-composite filled with 4wt.% talc was presented. Acting as filler and a reinforcing agent in the HDPE, talc powder, sized at around 5 μm, was surface-treated with aluminum diethylene glycol dinitrate coupling agent before adding to the HDPE. Analyses of the reinforced HDPE nano-composite show significant improvement in its mechanical properties including, tensile strength (>26 MPa), break elongation (<1.1%), flexural strength (>22 MPa), and friction coefficients<0.11. The results demonstrate that, after surface-treated, talc can be used as a promising filling material and a reinforcing agent in making HDPE nano-composite.

CLINICAL STUDY ON SPLEEN-STOMACH-REINFORCING MOXIBUSTION TREATMENT OF DIARRHEA-TYPE IRRITABLE BOWEL SYNDROME

In the present paper, the therapeutic effect of spleen- stomach- reinforcing moxibustion for treatment of irritable bowel syndrome (IBS) is observed and its underlying mechanisms on immunity are analyzed. A total of 72 IBS patients are randomly divided into moxibustion group (n= 46) and acupuncture group (control group, n = 26). Acu-points used are Zhongwan (CV 12), Qihai (CV 6) and Zusanli (ST 36), etc. Serum IgG, IgA and IgM contents, blood T-lympocytes (T3+, T4+, T8+) counts, T4+ /T8+, cancer embryonic antigen (CEA) content, serum IL-2 and slL-2R contents are assayed for evaluating changes of the immunocompetence. After two courses of treatment (24 sessions), results show that in moxibustion group, 25 cases (54.35%) are cured, 17 experience improvement in clinical symptoms and 4 have no apparent changes, with an effective rate of 91.30% ; in control group, 8 cases (30. 78%) are cured, 12 experience improvement and 6 have no marked improvement, with an effective rate of 76.92% . The therapeutic effect of moxibustion is significantly superior to that of acupuncture (P<0.01). In addition, moxibustion can effectively rectify abnormal immune function and stabilize human's immunity. This research provides a reliable experimental basis for clinical application of 'principal prescription of moxibustion for reinforcing the spleen and stomach'.

THE REINFORCING MECHANISM OF TiB2 IN TiB2/A357 COMPOSITE

Mechanical properties were tested for in situ TiB2/A357 composite fabricated by LSM (mixed salts reaction) method. Micro structures of as cast and plastic deformed TiB2/A357 were investigated. The results show that there is a low misfit between (200) Al and (101)TiB2 with [011]//Al [101]TiB2. There is a change from fully dendritic structure of the α-Al of A357 to a rosette-type structure of TiB2/A357. Significant increases in proof stress and Young's modulus can be obtained at low TiB2 additions. There exist dislocation loops around neighboring TiB2 particles with about 0.1μm in diameter and dislocation multiplication near TiB2 particles.

Mechanical and low-cycle fatigue behavior of stainless reinforcing steel for earthquake engineering applications

Use of stainless reinforcing steel （SRS） in reinforced concrete （RC） structures is a promising solution to corrosion issues. However, for SRS to be used in seismic applications, several mechanical properties need to be investigated. These include specified and actual yield strengths, tensile strengths, uniform elongations and low-cycle fatigue behavior. Three types of SRSs （Talley S24100, Talley 316LN and Talley 2205） were tested and the results are reported in this paper. They were compared with the properties of A706 carbon reinforcing steel （RS）, which is typical for seismic applications, and MMFX II, which is a high strength, corrosion resistant RS. Low-cycle fatigue tests of the RS coupons were conducted under strain control with constant amplitude to obtain strain life models of the steels. Test results show that the SRSs have slightly lower moduli of elasticity, higher uniform elongations before necking, and better low-cycle fatigue performance than A706 and MMFX II. All five types of RSs tested satisfy the requirements of the ACI 318 code on the lower limit of the tensile to yield strength ratio. Except Talley 2205, the other four types of RSs investigated meet the ACI 318 requirement that the actual yield strength does not exceed the specified yield strength by more than 18 ksi （124 MPa）. Among the three types of SRSs tested, Talley S24100 possesses the highest uniform elongation before necking, and the best low-cycle fatigue performance.

Controlling floor heave of extraction opening by reinforcing sides and roof

The effect of reinforcing roof, sides and floor corners to control floor heave of extraction opening was analyzed, It was proved by engineering practice and numerical simulation that reinforcing any part of surrounding rock have certainly control effect for floor heave, in the basis of this, the new way that roof, sides and floor corners were rein-forced to control floor heave was put forward. Contrasting control result of reinforcing floor with this, it is determined that reinforcing is more suitable to control floor heave of extrac-tion opening than reinforcing floor when advancing abutment pressure is in some range.

Factors Analysis of Affecting Loading and Reinforcing Scheme of Large Goods in Railway

Large goods transported in railway are kinds of special goods and they are very important in national construction. In order to transport safely, loading and reinforcing schemes must be made first. How to design a reasonable scheme will be affected by many factors. This paper presents the characteristic of the large goods, summarizes the process of designing a loading and reinforcing scheme of large good, then probes the factors of affecting the loading and reinforcing scheme and gives a detail analysis. It’s considered that those out-of-gauge and overweight degree of goods, center-of- gravity height of a loaded wagon, position of center-of-gravity of goods, type of wagon for using, reinforcement material and reinforcement method, transport expense and transport organization could affect a scheme in the aspects of safety, economy, rapidity and convenience. This conclusion will instruct and help to make a good scheme.

Comparative Studies of Steel, Bamboo and Rattan as Reinforcing Bars in Concrete: Tensile and Flexural Characteristics

This study comparatively evaluated the flexural performance and deformation characteristics of concrete elements reinforced with bamboo (Bambusa vulgaris), rattan (Calamuc deerratus) and the twisted steel rebars. The yield strength (YS), ultimate tensile strength (UTS) and the elongation of 50 specimens of the three materials were determined using a universal testing machine. Three beams of concrete strength 20 N/mm2 at age 28 days were separately reinforced with bamboo, rattan and steel bars of same percentage, while the stirrups were essentially mild steel bars. The beams were subjected to centre-point flexural loading according to BS 1881 to evaluate the flexural behaviour. The YS of bamboo and rattan bars were 13% and 45% of that of steel respectively, while their UTS were 16% and 62% of that of steel in the same order. The elongation of bamboo, rattan and steel were 7.42%, 10% and 14.7% respectively. The natural rebars were less than the 12% minimum requirement of BS 4449. The load-deflection plots of bamboo and steel RC beams were quadratic, while rattan RC beams had curvilinear trend. The stiffness of bamboo RC beams (BB) and rattan RC beams (RB) were 32% and 13.5% of the stiffness of steel RC beams (SB). The post-first crack residual flexural strength was 41% for BB and SB, while RB was 25%. Moreover, the moment capacities of BB and RB corresponded to 51% and 21% respectively of the capacity of steel RC beams. The remarkable gap between the flexural capacities of the natural rebars and that of steel can be traced not only to the tensile strength but also the weak bonding at the bar-concrete interface. It can be concluded that the bamboo bars are suitable rebars for non-load bearing and lightweight RC flexural structures, while more pre-strengthening treatment is required more importantly for rattan for improved interfacial bonding and load-carrying capacity.

Corrosion Measurements of Reinforcing Steel by Different Electrochemical Techniques

Electrochemical techniques of the corrosion measurements of reinforcing steeI in concrete have been evaluated. These techniques include half-cell potential measurements, impressed voltage method, impressed current method and potentiostatic polarization technique. The results of corrosion behaviour of the steel in both 5%NaCl and 5%MgSO4 show that each electrochemical technique provides some information about the condition of the steel bar or the corrosivity of the environment being evaluated, yet none provides a complete data regarding the corrosion resistance of reinforcing steel in aggressive media