High temperature effects in moving shock reflection with protruding Mach stem

The influence of high temperature effects on the protrusion of Mach stem in strong shock reflection over a wedge was numerically investigated. A two-dimensional inviscid solver applies finite volume method and unstructured quadrilateral grids were employed to simulate the flow. Theoretical analysis was also conducted to understand the phenomenon. Both numerical and theoretical results indicate a wall-jet penetrating forward is responsible for the occurrence of Mach stem protrusion. The protrusion degree seems to depend on the thermal energy buffer capacity of the testing gas. Approaches to increase the energy buffer capacity, such as vibrational relaxation, molecular dissociation, and increase of frozen heat caoacitv, all tend to escalate the orotrusion effect.

THE EFFECT OF THE CBN WHEEL DRESSING AND THE GRAIN HEIGHT PROTRUDING FROM THE BOND ON THE GRINDING PERFORMANCE

CBN (Cubic Boron Nitride) is a highly efficient abrasive and has unique properties (highhardness, high thermal stability and high chemical inertia). As early as 1969 CBN Wheels had al-ready been made and showed excellent performance for grainding high speed steels and othermaterials hard to be ground. So far, however, CBN Wheels are still not popularly utilized in theindustry, the writer considers the main reason being the inadequate study for practical applica-tions and especially the suitable dressing technique. The dressing of resinoid CBN Wheels discussed in the paper, is different from that ofconventional ones. It has to be divided into two operations, truing and sharpening, each of whichhas its specific and independent functions. A simple dressing method with a lot of informationsuitable for production is studied; finally, the grain height protruding from the bond is taken asan index for evaluating the dressing results, and the effect of grain height on the grinding per-formance is discussed. By selecting proper conditions according to the workpiece requirements, abetter technical and economical benifit can be obtained.

The Protruding Property in Fuzzy Comprehensive Judgment

When applying the comprehensive judgment model in making policies, we find that its protruding property is quite essential. Without this protruding property, policy-making be comes impossible and even contradictions emerge. this paper deals the protruding property and its influence on the comprehensive judgment, gives the full conditions for producing the protruding property and improves the model of the comprehensive judgment from the theory and the application.

Study on a Bowl-based Mechanism for Transplanting Potted Strawberry Seedlings

To improve the efficiency of fetching and transplanting seedlings for the mechanization of strawberry planting,an integrated transplanting mechanism was designed with protruding,fetching and planting performance to achieve rapid fetching and pushing bowl movements.According to the working principle of the slewing mechanism,a kinematics model and the optimization goal were established,respectively.Based on visual auxiliary analysis software,optimal parameters were obtained.A three-dimensional model was established to obtain a simulation trajectory by means of a virtual simulation design analysis.Three-dimensional printing technology was used to manufacture the test prototype,and the actual working trajectories of the test prototype were extracted using high-speed photography technology,which verified the consistency of the actual trajectory with the theoretical and simulated trajectories.A prototype transplanting experiment was performed with the success rate of seedling extraction of 91.2%and excellent planting rate of 82.8%,which met the requirements for integrated strawberry harvesting,planting and transplanting.The experimental results verified the correctness and feasibility of the design of integrated transplanting mechanism.

Automatic Determination of Yarn Hairiness Length Based on Image Processing and Analysis Algorithm

A new algorithm is proposed to determine the actual length and the number of the protruding fibres of yarn based on a combination of image acquisition technology. First, a yarn hairiness image is obtained by the series of image processing procedures that include grayscale transformation,skew correction,yarn binary image acquisition and yarn core binary image obtaining. Then,the hairiness is realized in single pixel width by the usage of thinning algorithm. Finally, a baseline of yarn core margin is obtained,and pixels that match 8-neighbor template correctly are found by row scanning in a certain area. From this,these pixels are judged and the real crossover points of yarn core margin and hairiness,i. e.,the starting points of hairiness,are gained. The real length of the protruding fibres is calculated by tracking hairiness from the starting point constantly.

rate of adverse events of gastroduodenal snare polypectomy for non-flat polyp is low: A prospective and multicenter study

AIM To evaluate the rate of adverse events(AEs) during consecutive gastric and duodenal polypectomies in several Spanish centers. METHODS Polypectomies of protruded gastric or duodenal polyps ≥ 5 mm using hot snare were prospectively included. Prophylactic measures of hemorrhage were allowed in predefined cases. AEs were defined and graded according to the lexicon recommended by the American Society for Gastrointestinal Endoscopy. Patients were followed for 48 h, one week and 1 mo after theprocedure. RESULTS308 patients were included and a single polypectomy was performed in 205. Only 36(11.7%) were on prior anticoagulant therapy. Mean polyp size was 15 ± 8.9 mm(5-60) and in 294 cases(95.4%) were located in the stomach. Hemorrhage prophylaxis was performed in 219(71.1%) patients. Nine patients presented AEs(2.9%), and 6 of them were bleeding(n = 6, 1.9%)(in 5 out of 6 AE, different types of endoscopic treatment were performed). Other 24 hemorrhagic episodes could be managed without any change in the outcome of the endoscopy and, consequently, were considered incidents. We did not find any independent risk factor of bleeding.CONCLUSION Gastroduodenal polypectomy using prophylactic measures has a rate of AEs small enough to consider this procedure a safe and effective method for polyp resection independently of the polyp size and location.

Self-assembled multiepitope nanovaccine based on NoV P particles induces effective and lasting protection against H3N2 influenza virus

Current seasonal influenza vaccines confer only limited coverage of virus strains due to the frequent genetic and antigenic variability of influenza virus(IV).Epitope vaccines that accurately target conserved domains provide a promising approach to increase the breadth of protection;however,poor immunogenicity greatly hinders their application.The protruding(P)domain of the norovirus(NoV),which can self-assemble into a 24-mer particle called the NoV P particle,offers an ideal antigen presentation platform.In this study,a multiepitope nanovaccine displaying influenza epitopes(HMN-PP)was constructed based on the NoV P particle nanoplatform.Large amounts of HMN-PP were easily expressed in Escherichia coli in soluble form.Animal experiments showed that the adjuvanted HMN-PP nanovaccine induced epitope-specific antibodies and haemagglutinin(HA)-specific neutralizing antibodies,the antibodies could persist for at least three months after the last immunization.Furthermore,HMN-PP induced matrix protein 2 extracellular domain(M2e)-specific antibody-dependent cell-mediated cytotoxicity,CD4^(+)and CD8^(+)T-cell responses,a nucleoprotein(NP)-specific cytotoxic T lymphocyte(CTL)response.These results indicated that the combination of a multiepitope vaccine and self-assembled NoV P particles may be an ideal and effective vaccine strategy for highly variable viruses such as IV and SARS-CoV-2.