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Purpose This study aimed to clarify the resting-state cerebral blood flow alteration patterns induced by primary dysmenorrhea, investigate the relationships between cerebral blood flow alterations and clinical parameters of patients with primary dysmenorrhea, and explore whether brain regions with abnormal cerebral blood flow also feature functional connectivity changes. Methods Arterial spin labeling imaging and clinical parameters were acquired in 42 patients with primary dysmenorrhea and 41 healthy controls during their menstrual phases. Differences in cerebral blood flow were compared between the two groups, and the clusters with significant group differences were selected as the regions of interest for further statistical analyses. Results Compared to healthy controls, patients with primary dysmenorrhea exhibited increased cerebral blood flow in the bilateral precuneus, left posterior cingulate cortex, and right rolandic operculum. Among patients with primary dysmenorrhea, we identified a negative correlation between the cerebral blood flow in the right rolandic operculum and the visual analogue score for anxiety, and greater correlation between the functional connectivity in the precuneus/posterior cingulate cortex and the right middle cingulate cortex, and between the right rolandic operculum and the left inferior parietal lobule and the bilateral postcentral gyrus. Discussion Cerebral blood flow abnormalities associated with primary dysmenorrhea were mainly concentrated in the areas comprising the default mode network in primary dysmenorrhea patients, which could be involved in the central mechanism of primary dysmenorrhea. Cerebral blood flow alteration in the rolandic operculum may underlie an anxiety-induced compulsive tendency in patients with primary dysmenorrhea. Investigating the enhanced connectivity among various pain-related brain regions could improve understanding of the onset and development of primary dysmenorrhea.

Erectile dysfunction (ED) is a common comorbidity in males with diabetes. In this study, we aimed to investigate how lncRNA-MIAT affects ED in diabetes and the involved mechanism. Microarray analysis was performed to screen ED-related differentially expressed genes, regulatory microRNA (miR) and long noncoding RNA (lncRNA). Highly expressed lipoprotein lipase (LPL) was identified, and subsequently miR-328a-5p and lncRNA-MIAT were determined. Diabetes was induced by streptozotocin in rats, and diabetic rats with ED were selected. Vascular smooth muscle cells (VSMCs) and vascular endothelial cells (VECs) were cocultured. The siRNA against lncRNA-MIAT, miR-328a-5p mimic and overexpression vector of LPL were transfected to investigate the specific effects of miR-328a-5p, lncRNA-MIAT and LPL on ED in diabetes. The expression of LPL, lncRNA-MIAT and miR-328a-5p in the serum of diabetic patients was measured. Increased LPL and lncRNA-MIAT and reduced miR-328a-5p were observed in diabetic patients. In addition, ED led to upregulated LPL and lncRNA-MIAT and downregulated miR-328a-5p in serum of diabetic patients and VSMCs of diabetic rats, especially in those with ED. LncRNA-MIAT directly regulated miR-328a-5p, which directly targeted LPL. LncRNA-MIAT upregulated LPL by acting as a ceRNA of miR-328a-5p. Silencing of lncRNA-MIAT and LPL or miR-328a-5p overexpression reduced VEC apoptosis and increased cell proliferation. In addition, an increased intracavernosal pressure (ICP)/mean arterial pressure (MAP) ratio was noted in the corpus cavernosum of rats and inhibited VEC injury. Taken together, our data demonstrated that depleted lncRNA-MIAT suppressed LPL by increasing miR-328a-5p, thereby inhibiting VEC injury to attenuate ED in diabetic rats.

Gas pores on the top face of engine crankcases which are produced by Low Pressure Die Casting (LPDC) have been studied. Micrographic analysis has been conducted to investigate the evolution of such kind of casting defects. Results show that the surface of such casting defects have meandering shapes and random sizes. Microstructures of the cross section of the defects displayed folded feather shapes, which can be produced by the folded oxide film into the melt during the filling process. Oxide inclusions have been found below the filter at the ingate area. Thus, it is confirmed that the folded oxide films came from turbulence of the metal in the die cavity. Numerical simulation has been carried out to study the filling behavior of the crankcase. Results show that gating velocity suddenly increased when the liquid metal got into the waterfall structure and led to the turbulence. Moreover, the air entrained behavior is related with the gating velocity. With increasing gating velocity, turbulence happened when metal confluences, and became more intensely in the middle of the casting due to its waterfall structure. Finally, this kind of casting defect was confirmed as gas entrainment.

The pure electric vehicles and hybrid vehicles mostly use single battery pack for energy storage, which is easy to cause various battery problems. Moreover, short driving range and inconvenient charging are still the restrictive factors for the development and promotion of electric vehicles. A new kind of dynamic driving system was proposed in this paper -- Load isolated pure electric driving. According to the performance requirements of load isolated pure electric driving vehicle we made homologous parameter matching of the power system, and the driving system control strategy was carried on analysis based on the SOC of power batteries and the running conditions of vehicle.

When a stratospheric satellite travels by prevailing winds in the stratosphere, its cross-track displacement needs to be controlled to keep a constant latitude orbital flight. To design the orbit control system, a 6 degree-of-freedom (DOF) model of the satellite is established based on the second Lagrangian formulation, it is proven that the input/output feedback linearization theory cannot be directly implemented for the orbit control with this model, thus three subsystem models are deduced from the 6-DOF model to develop a sequential nonlinear control strategy. The control strategy includes an adaptive controller for the balloon-tether subsystem with uncertain balloon parameters, a PD controller based on feedback linearization for the tether-sail subsystem, and a sliding mode controller for the sail-rudder subsystem with uncertain sail parameters. Simulation studies demonstrate that the proposed control strategy is robust to uncertainties and satisfies high precision requirements for the orbit flight of the satellite.

The pure electric vehicles and hybrid vehicles mostly use single energy storage battery pack, which easily cause various battery problems. Moreover, short driving range and inconvenient charging are still the key problems to be solved. A new kind of dynamic driving system aiming at these problems was put forward in this paper--Load isolated pure electric driving. This paper made homologous parameter matching of power system and established full vehicle dynamic model of Load isolated pure electric driving vehicle by MATLAB/SIMULINK, the feasibility and advantage of the Load isolated pure electric driving system was verified through performance simulation.

Drug resistance is one of the main causes of colon cancer recurrence. However, our understanding of the underlying mechanisms and availability of therapeutic options remains limited. Here we show that expression of pyruvate dehydrogenase kinase 4 (PDK4) is positively correlated with drug resistance of colon cancer cells and induced by 5-fluorouracil (5-FU) treatment in drug-resistant but not drug-sensitive cells. Knockdown of PDK4 expression sensitizes colon cancer cells to 5-FU or oxaliplatin-induced apoptosis in vitro and increases the effectiveness of 5-FU in the inhibition of tumor growth in a mouse xenograft model in vivo In addition, we demonstrate for the first time that TGFβ mediates drug resistance by regulating PDK4 expression and that 5-FU induces PDK4 expression in a TGFβ signaling-dependent manner. Mechanistically, knockdown or inhibition of PDK4 significantly increases the inhibitory effect of 5-FU on expression of the anti-apoptotic factors Bcl-2 and survivin. Importantly, studies of patient samples indicate that expression of PDK4 and phosphorylation of Smad2, an indicator of TGFβ pathway activation, show a strong correlation and that both positively associate with chemoresistance in colorectal cancer. These findings indicate that the TGFβ/PDK4 signaling axis plays an important role in the response of colorectal cancer to chemotherapy. A major implication of our studies is that inhibition of PDK4 may have considerable therapeutic potential to overcome drug resistance in colorectal cancer patients, which warrants the development of PDK4-specific inhibitors.

This paper provides a solution for the position tracking and attitude synchronization problem of the close proximity phase in spacecraft rendezvous and docking. The chaser spacecraft must be driven to a certain fixed position along the docking port direction of the target spacecraft, while the attitude of the two spacecraft must be synchronized for subsequent docking operations. The kinematics and dynamics for relative position and relative attitude are modeled considering dynamic coupling, parametric uncertainties and external disturbances. The relative motion model has a new form with a novel definition of the unknown parameters. An original robust adaptive control method is developed for the concerned problem, and a proof of the asymptotic stability is given for the six degrees of freedom closed-loop system. A numerical example is displayed in simulation to verify the theoretical results.

Objective To compare the therapeutic effect of arterial and lymphatic sparing microscopic retroperitoneal varicocelectomy (MRV) with that of microscopic subinguinal varicocelectomy (MSV) for treatment of varicocele in infertile men. Methods We conducted a prospective and controlled study to evaluate the therapeutic efficacy of MRV and MSV for treatment of varicocele in infertile men. A total of 80 patients were randomly chosen to undergo MRV (n = 40) or MSV (n = 40) treatment. All patients were followed up at 3, 6, and 12 months after surgery. Semen parameters, pregnancy, recurrence, and complications were examined. Results Mean operation time in the MRV group was significantly shorter than that in MSV group (38.92 ± 5.67 min vs 91.35 ± 15.08 min), and the number of observed spermatic veins in MRV group was significantly less than that in MSV group (3.59 ± 0.76 vs 18.22 ± 2.83). Sperm count and motility were significantly improved at 12 months follow-up in both groups compared with preoperative values, and the sperm count in the MRV group at 3 months was significantly higher than that in MSV group. Moreover, the incidence of scrotal edema was higher in the MSV group, although natural pregnancy rate was not significantly different between 2 groups at 1-year follow-up (42.1% vs 44.7%). Conclusion MRV with artery and lymphatic sparing is a simple and effective technique for treatment of varicocele in infertile men.

The steam-gasification reaction characteristics of coal and petroleum coke (PC) were studied in the drop tube furnace (DTF). The effects of various factors such as types of carbonaceous material, gasification temperature (1100–1400 °C) and mass ratio of steam to char (0.4:1, 0.6:1 and 1:1 separately) on gasification gas or solid products were investigated. The results showed that for all carbonaceous materials studied, H2 content exhibited the largest part of gasification gaseous products and CH4 had the smallest part. For the two petroleum cokes, CO2 content was higher than CO, which was similar to Zun-yi char. When the steam/char ratio was constant, the carbon conversion of both Shen-fu and PC chars increased with increasing temperature. When the gasification temperature was constant, the carbon conversions of all char samples increased with increasing steam/char ratio. For all the steam/char ratios, compared to water gas shift reaction, char-H2O and char-CO2 reaction were further from the thermodynamic equilibrium due to a much lower char gasification rate than that of water gas shift reaction rate. Therefore, kinetic effects may play a more important role in a char gasification step than thermodynamic effects when the gasification reaction of char was held in DTF. The calculating method for the equilibrium shift in this study will be a worth reference for analysis of the gaseous components in industrial gasifier. The reactivity of residual cokes decreased and the crystal layer (L002/d002) numbers of residual cokes increased with increasing gasification temperature. Therefore, L002/d002, the carbon crystallite structure parameter, can be used to evaluate the reactivity of residual cokes.

This paper studies the relative position tracking and attitude synchronization of non-cooperative spacecraft rendezvous with model uncertainty and external disturbance. The relative position vector between the chaser spacecraft and the non-cooperative target is required to direct towards the docking port of the target, while the attitude of the two spacecrafts must be synchronized. The coupled six degrees-of-freedom (6DOF) dynamics are modeled for spacecraft relative motion, where the modified Rodrigues attitude parameters are employed to describe relative attitude dynamics. In view of the thrust misalignment of the chaser spacecraft, an integrated robust adaptive controller for 6DOF relative motion is designed, where parametric uncertainties of the chaser spacecraft are estimated online by using gradient adaptive method, and dynamic coupling effect resulting from unknown inertial parameters of the target is handled with a norm-estimation-based adaptive method. It is proved via the Lyapunov theory that the closed-loop system errors asymptotically converge to zero. Numerical simulation example demonstrates theoretical results.

Catalytic pyrolysis and gasification characteristics of coal using Na2CO3 as a catalyst were studied in a high-frequency furnace and thermogravimetric analyzers (TGA), respectively. Interactions of Na2CO3 with carbon at both pyrolysis and gasification phases were observed by in-situ heating stage microscope. The effects of pyrolysis temperature (650–800 °C) and catalyst loading amount (0–15 wt.%) on the associated pyrolysis and gasification processes were investigated. The results show that, H2 and CO are the main pyrolysis gas products and the yields of these two gas increase with the increasing of Na2CO3 in the range of 0–15 wt.%. The in-situ heating stage experiments indicated that one main gasification reaction form was observed for Shenfu char samples. Most of SF char particles reacted with CO2 in the form of shrinking core mode without cracking, and certain particles presented fragmentation phenomenon in the reaction process. There is an optimal loading amount of Na2CO3 for the best catalytic gasification effect of Shenfu bituminous char, while Na2CO3 does not reach the saturation amount for the catalytic gasification of Zunyi anthracite coal. The activation energy of catalytic Shenfu coal gasification with 10 wt.% Na2CO3 is 31.5 kJ mol−1 less than that of non-catalytic coal gasification, which indicates that Na2CO3 can improve the kinetics of coal gasification with CO2.

A nonlinear control is proposed for trajectory tracking of a 6-DOF model-scaled helicopter with constraints on main rotor thrust and fuselage attitude. In the procedure of control design, the mathematical model of helicopter is simplified into three subsystems: altitude subsystem, longitudinal-lateral subsystem and attitude subsystem. The proposed control is developed by combining the sub-controls for the corresponding subsystems. The sub-controls for altitude subsystem and longitudinal-lateral subsystem are designed with hyperbolic tangent functions to satisfy the constraints; the sub-control for attitude subsystem is based on backstepping technique such that fuselage attitude tracks the virtual control for longitudinal-lateral subsystem. It is proved theoretically that tracking errors are ultimately bounded, and control constraints are satisfied. Performances of the proposed controller are demonstrated by simulation results.

Reactivities of three chars with CO2 and steam were examined using a Thermogravimetric Analyzer (TGA). Similarities and differences between kinetics of char–CO2 gasification and char–steam gasification have been discussed. As a result, for both reactions, the measured gasification rate increases with temperature and decreases as the particle size increases. And the initial rate of char–steam gasification is always several times faster than that of char–CO2 gasification. Moreover, for the char with lower reactivity, the activity of its steam gasification reaction possesses larger difference with that of CO2 reaction. An nth-order model with the effectiveness factor was used and a characteristic parameter (Tc, which is the temperature in the case of Thiele modulus ϕ = 3.) was proposed to compare the difference between the pore diffusion effect on steam gasification and CO2 gasification. The results show that the pore diffusion resistance increases with the gasification temperature and particle size. However, for each sample, Tc of char–steam gasification is always lower than that of char–CO2 gasification. The pore diffusion effect on char–steam gasification is more significant than that on char–CO2 gasification. Moreover, the difference between the pore diffusion effect on char–steam gasification and char–CO2 gasification is larger for the char with lower reactivity.

CO2 gasification with different coals and a petroleum coke from China were performed in a thermogravimetric analyzer (TGA). Initial gasification rates of these sample chars were measured at different gasification temperatures (850–1300 °C) and four particle sizes (

Gasification reactivities of six different carbonaceous material chars with CO2 were determined by a Thermogravimetric Analyzer (TGA). Gasification reactivities of biomass chars are higher than those of coke and coal chars. In addition, physical structures and chemical components of these chars were systematically tested. It is found that the crystalline structure is an important factor to evaluate gasification reactivities of different chars and the crystalline structures of biomass chars are less order than those of coke and coal chars. Moreover, initial gasification rates of these chars were measured at high temperatures and with relatively large particle sizes. The method of calculating the effectiveness factor η was used to quantify the effect of pore diffusion on gasification. The results show that differences in pore diffusion effects among gasification with various chars are prominent and can be attributed to different intrinsic gasification reactivities and physical characteristics of different chars.

A novel path following control method related to the planar and spatial motions for an underactuated autonomous airship is presented. First, the trajectory linearisation control (TLC) theory is briefly described and the dynamic model of the airship is introduced. Then, based on the model, a path following strategy that integrates the guidance-based path following principle and the TLC theory is deduced. The designed control system possesses a cascaded structure composed of a guidance loop, an attitude kinematics loop and a dynamics control loop. Stability analysis shows that the controlled closed-loop system is asymptotically stable. Finally, experimental flight results for the airship following typical paths are illustrated to verify the effectiveness of the proposed approach.

A phenomenon commonly encountered in grinding of silicon wafers is the grinding marks, which are difficult to remove by subsequent polishing process, and have been a great obstacle to the manufacture of silicon wafers with higher flatness. In this paper, the grinding marks formation mechanism was clarified, a grinding marks formation model and an angular wavelength model were developed, and a grinding marks suppression method was proposed. A series of grinding experiments were carried out to verify the developed models and investigate the effect of the wafer rotational speed, the wheel rotational speed, the infeed rate, the axial run out of the cup wheel and the spark out time. The results show that: (1) grinding marks are waviness generated on silicon wafers caused by non-uniform material removal circumferentially due to the axial run out of the cup wheel; (2) grinding marks present multiple angular wavelengths characteristics; (3) the angular wavelength of grinding marks is a one-variable function of the rotational speed ratio of the wheel to the wafer; and (4) grinding marks could be suppressed significantly by properly selecting the rotational speed ratio.

Stratospheric airship is a new kind of aerospace system which has attracted worldwide developing interests for its broad application prospects. Based on the trajectory linearization control (TLC) theory, a novel trajectory tracking control method for an underactuated stratospheric airship is presented in this paper. Firstly, the TLC theory is described sketchily, and the dynamic model of the stratospheric airship is introduced with kinematics and dynamics equations. Then, the trajectory tracking control strategy is deduced in detail. The designed control system possesses a cascaded structure which consists of desired attitude calculation, position control loop and attitude control loop. Two sub-loops are designed for the position and attitude control loops, respectively, including the kinematics control loop and dynamics control loop. Stability analysis shows that the controlled closed-loop system is exponentially stable. Finally, simulation results for the stratospheric airship to track typical trajectories are illustrated to verify effectiveness of the proposed approach.

This paper reports a new kinematics for ultra precision grinding of conical surfaces. It uses a rotary table and a cup wheel to perform an infeed grinding. Its principle is that the generating curve of the grinding wheel is locally flat and the locally flat portion can be approximated by a sloping line segment if the machine configuration parameters such as the wheel radius, the center distance between the rotary table and the wheel, the wheel inclination angle and the rotary table direction angle are properly selected. A model for the conicity error of the generated surface was developed. An algorithm for the selection of the desired values of the machine configuration parameters to grind conical surfaces was proposed. It was found that the minimum theoretical conicity error is extremely small for narrow conical surface or conical surface with shallow radial inclination angle. It is expected to be an efficient method to manufacture the conical surfaces of machine parts, mechanical sealing components and optical devices with high form accuracy, low surface roughness and low subsurface damage.

A novel counter-gravity infiltration casting device and corresponding fabricating process for producing open-celled aluminum foams were presented. The experimental results show that defects such as insufficient or excessive infiltrating can hardly be found in the foam samples prepared by counter-gravity infiltration casting. The foam materials exhibit excellent mechanical properties. The void content strongly affects the mechanical properties of aluminum foams. The yield stress and plateau stress significantly increase with the decrease of void content. Raising pre-heating temperature and increasing packing pressure are effective to lower the void content in aluminum foams.

The flow field structures can have a large influence on both flow velocity and temperature distributions of the direct methanol fuel cells (DMFCs), thus proper flow field constructions are very important for the improvement in DMFC’s performance. In this work, anodic flow velocity and temperature distributions based on four different designs, including double serpentine, parallel, helix and single serpentine, were simulated in three-dimensional models. Computational fluid dynamics (CFD) was used to investigate the effects of flow field structures on the DMFC’s performance. Simulated results indicate that the double-serpentine flow field shows better flow velocity distribution and more uniform temperature distribution, which might lead to a better performance of the DMFC. Further experimental investigation on four types of flow fields also confirmed that the DMFC with double-serpentine flow field structure exhibits a maximal power density at a variety of inlet velocities, which is in good agreement with the simulated results. The maximum power density of the fabricated DMFC with double-serpentine flow field is ca. 34.2 mW cm −2 when the inlet flow velocity was 0.01 m s −1 at room temperature.

The IEEE 802.15.4 is one of the low-layer communication standards for personal area networks (PANs) and wireless sensor networks (WSNs), which may be interfered by other wireless devices in the industrial, scientific and medical (ISM) frequency bands, especially in home environment, such as devices of IEEE 802.11b, Bluetooth, cordless telephone, and microwave oven radiation. This article examines the mutual interference effects of 2.4 GHz devices widely deployed at home, via both theoretical analysis and real-life experiment. An analytical model is proposed to estimate the packet error rate (PER) of radio frequency (RF) coexistent networks. The model is verified through a series of experiments. The experimental results also show that Bluetooth has little impact of interference on IEEE 802.15.4 sensor networks, and that the effect of microwave oven radiation on IEEE 802.15.4 sensor devices is tolerable if the device is a few meters away from the oven. Whereas, IEEE 802.11b wireless networks can cause problems to IEEE 802.15.4, however the effects can be significantly reduced by a proper channel selection. This article also proposes the interference duration model, which will be helpful in modeling of coexistence simulation. Simulation results show that the stationary scenario obeys the experiments result very well.

The thermal stability, particle size and morphology and oil absorption of aluminum hydroxide(ATH) treated by dry modification with three different modifiers were investigated. The experimental results show that the thermal stability of ATH powder is markedly improved by dry modification technology with the following modifiers such as phosphoric acid, polyacrylic acid and the mixture of phosphoric acid and polyacrylic acid. The best effect comes from pure phosphoric acid, and the initial temperature for the loss of crystal water of ATH powder modified with pure polyacrylic acid can reach about 202 °C that is approximately 10 °C higher than that of ATH powder before modification. The phenomena of agglomeration and macro-aggregate badly exist in ATH powder modified with the modifiers containing phosphoric acid. The growth of particles and agglomerations of powders are not evident in ATH powder modified with pure polyacrylic acid. The oil absorption of ATH powder modified with the modifiers containing phosphoric acid is apparently larger than that of original ATH powder and ATH powder modified with pure polyacrylic acid. The oil absorption of the ATH powder modified with pure polyacrylic acid is slightly smaller than that of original ATH powder.

This paper investigates the problem of survivable traffic grooming (STG) in shared mesh optical networks and proposes different frameworks for improving the survivability of low speed demands against multiple near simultaneous failures. Spare capacity reprovisioning has recently been considered for improving the overall network restorability in the event of dual failures; here, after the recovery form the first failure, some connections in the network may become unprotected and exposed to new failures. Capacity reprovisioning then allocates protection resources to unprotected and vulnerable connections so that the network can withstand a future failure. In this paper, we propose two different reprovisioning schemes (lightpath level reprovisioning, LLR, and connection level reprovisioning, CLR); they differ in the granularity at which protection resources are reprovisioned. Further, each of these schemes is suitable for a different survivable grooming policy. While LLR provides collective reprovisioning of connections at the lightpath level, CLR reprovisions spare bandwidth for lower speed connections instead. We use simulation methods to study the performance of these schemes under two grooming policies (PAL and PAC), and we show that while CLR reprovisions substantially many more connections than LLR (i.e., potentially more management overhead) CLR yields a much better network robustness to simultaneous failures due to its superior flexibility in using network resources.

The effects of stainless steel powder particle size, sintering temperature and soaked time on the oxidation resistance performance of foam with 3D open-cell network structure at 800 °C were mainly investigated, and the improvement mechanism of Cr 3 C 2 on the oxidation resistance performance of foam was also discussed in this paper. The experimental results show that the oxidation resistance performance of foam improves with the decrease of stainless steel powder particle size, the increase of sintering temperature and the prolongation of soaked time, which may be due to the facts that the fine particle size, high sintering temperature and long soaked time can make the foam sintered compactly and the oxidizable interface between foam and air medium shrink, at the same time, the open porosity of foam decreases; the addition of Cr 3 C 2 is effective to improve the oxidation resistance ability of foam at high temperature due to that the preferential formation of excessive compact anti-oxidation Cr 2 O 3 film in the existence of Cr 3 C 2 ; however, the bending strength decrease with the content of Cr 3 C 2 rising.

Current restoration signaling is a two-phase messaging procedure between the sender and the receiver and depends heavily on the message propagation delays during the recovery process and the cross-connect switching times. Offset time (OT) based restoration was proposed in [C. Assi, Y. Ye, S. Dixit, M. Ali. Control and management protocols for survivable optical mesh networks, IEEE Journal of Lightware Technology, November 2003.] to address the impact of these parameters and upper bound (OT-UB) expressions were derived. However, our closer investigation showed that as the network conditions change (e.g. increasing the number of wave-length channels per link) the benefits this restoration paradigm offer rapidly diminish, thereby rendering the argument of avoiding conventional restoration signaling inappropriate. In this paper, we propose a more accurate model to estimate the OT of each failed connection using a time-driven scheduling procedure. We also study the applicability of the proposed recovery protocol under double link failures assumption and we propose extensions to the protocol. We evaluate our proposal through simulation experiments and we show that substantial restoration gain can be achieved under varying network conditions.

This paper addresses the problem of feedback stabilization of nonholonomic chained systems within the framework of nonregular feedback linearization. Firstly, the nonsmooth version of nonregular feedback linearization is formulated, and a criterion for nonregular feedback linearization is provided. Then, it is proved that the chained form is linearizable via nonregular feedback control, thus enable us to design feedback control laws using standard techniques for linear systems. The obtained discontinuous control laws guarantee convergence of the closed-loop system with exponential rates. Finally, simulation results are presented to show the effectiveness of the approach.

In this paper, a fiber optic acoustic sensor system is designed and tested for on-line detection of the partial discharges inside high voltage power transformers. The fiber optic sensor uses a silica diaphragm and a single mode optical fiber encapsulated in a silica glass tube to form an extrinsic Fabry–Perot interferometer. Test results indicate that the developed fiber optic sensors are capable of detecting the acoustic signals propagating inside the transformer oil with high resolution and high frequency.

This paper deals with stabilization problem of nonholonomic wheeled mobile robots with unknown inertia parameters. Novel adaptive quasi-exponentially stabilizing laws (see Section 3 for definition) are presented based on new canonical forms and their two key facts. Extensive simulation demonstrates effectiveness of the control scheme.

An inactivated golden hamster kidney cell culture (GHKC) vaccine against haemorrhagic fever with renal syndrome (HFRS) has been developed in recent years. A monovalent GHKC vaccine (lot 88-17) was prepared with L99 strain of the rat-type hantavirus, adapted in suckling mouse brain, cultivated in GHKC, and inactivated with 0.025% formalin, and a preliminary trial of the vaccine was carried out in a small number of human volunteers with the approval of the Ministry of Public Health, PRC, in order to identify safety and antibody response of the vaccine. Three inoculations were made on days 0, 7 and 28 respectively, by the intramuscular route with 1 ml vaccine each time for every volunteer. No obvious side effect was observed in vaccinees within 3 days after each inoculation. All 12 vaccinees (10 received three inoculations, and two received two inoculations of the vaccine) showed positive seroconversion of IgG antibody (by IFAT and ELISA) and neutralizing antibody (by enzyme focus reduction neutralization test, EFRNT), and 10 of them were still seropositive 180 and 360 days after the first inoculation. These results suggest that this vaccine would be safe for human use, and could effectively induce IgG and neutralizing antibody responses.