Dynamic response of UHMWPE plates under combined shock and fragment loading

Ultra-high molecular weight polyethylene(UHMWPE)fiber composite has been extensively used to construct lightweight protective structures against ballistic impacts,yet little is known about its performance when subjected to combined blast and fragment impacts.Built upon a recently developed laboratory-scale experimental technique to generate simulated combined loading through the impact of a fragment-foam composite projectile launched from a light gas gun,the dynamic responses of fullyclamped UHMWPE plates subjected to combined loading were characterized experimentally,with corresponding deformation and failure modes compared with those measured with simulated blast loading alone.Subsequently,to explore the underlying physical mechanisms,three-dimensional(3D)numerical simulations with the method of finite elements(FE)were systematically carried out.Numerical predictions compared favorably well with experimental measurements,thus validating the feasibility of the established FE model.Relative to the case of blast loading alone,combined blast and fragment loading led to larger maximum deflections of clamped UHMWPE plates.The position of the FSP in the foam sabot affected significantly the performance of a UHMWPE target,either enhancing or decreasing its ballistic resistance.When the blast loading and fragment impact arrived simultaneously at the target,its ballistic resistance was superior to that achieved when subjected to fragment impact alone,and benefited from the accelerated movement of the target due to simultaneous blast loading.

Performance Quality Testing under Combined Loading of Polyethylene Pipes Reinforced with Aramid Fiber

This paper presents the results of the performance quality testing of polyethylene pipes reinforced with aramid fibers, intended for applications such as discharging and gathering oil pipelines, and describes the test rig specifically designed for this purpose. The pipe specimens are submitted to impact with a device that simulates the collision of a pickaxe, and of a backhoe loader. After the impact, the pipes are tested under combined loading comprising internal pressure, and transverse loading; some pipe specimens without previous impact are tested as well. The results show that the reinforced thermoplastic pipes can fully withstand maximal operating pressure levels in the presence of damage and additional transverse loading.

Performance study of combined test rig for metro train traction

This paper deals with a combined test rig for a traction system in the laboratory environment.An experimental system was designed and implemented to verify the performance of the traction system for a metro train.For a highly accurate control of the system,a hybrid control algorithm combining vector control and slip frequency control was applied to control the traction inverter.The design method of the flywheels,which represent the equivalent model of the train moment inertia,was elaborated.A train runtime diagnosis system was completed by adopting the multifunction vehicle bus（MVB） protocol.The dynamic performance of the metro power traction system was emulated under the control of the train runtime diagnosis system.Using the combined test rig,the performances of the traction system in traction,braking,temperature rise,etc.,were verified through traction and breaking experiments.

Study on the Diagnostic Value of Combined Detection of Sperm Quality, Sex Hormone and Ovulation in Infertility

Objective: To analyze the application value of combined detection of sperm quality, sex hormone and ovulation in the diagnosis of infertility. Methods: The study was conducted from June 2021 to June 2022. Sixty infertile couples who received IVF cycle treatment in our hospital during this period were selected as the observation group, and 60 couples with good sperm quality and follicle number ≥ 5 who conceived naturally after gynecological disease treatment were selected as the control group during the same period. The sperm quality, sex hormones and ovulation of the two groups were observed, and the change of positive rate was detected by the combined detection method. Results: Compared with the control group, the observation group had less semen (2.82 ± 0.12) ml, lower concentration (69.17 ± 1.28) × 106/ml, normal sperm morphology rate (2.92% ± 0.11%), lower survival rate (70.25% ± 1.16%), higher deformed sperm index (1.39 ± 0.11), and significant differences between groups (P < 0.05);The levels of FSH (7.15 ± 1.33) U/L, LH (5.13 ± 0.53) mU/ml, E2 (72.34 ± 5.11) ng/L, AMH (3.87 ± 0.67) ng/ml and AFC (7.15 ± 0.76) in the control group were significantly better than those in the observation group (P < 0.05). Compared with the single detection method of the three groups, the positive detection rate of the combined diagnosis method was higher, and the difference between the groups was significant (P < 0.05). Conclusion: For the diagnosis of infertility, the combined detection method of sperm quality, sex hormone and ovulation can effectively clarify the problems existing in the couple, significantly improve the detection rate of the cause of the patient, and is more conducive to guiding clinical symptomatic treatment, which is worthy of promotion and reference.

The Clinical Study of Multigene Combination Test to Guide Chemotherapy Combined with Targeted Therapy in Patients with Advanced Gastrointestinal Tumors

Objective:To study the clinical effects of multigene combination test to guide chemotherapy combined with targeted therapy in patients with advanced gastrointestinal tumors.Methods:The samples were selected from 60 patients with advanced gastrointestinal tumors admitted to our hospital from March 2019 to July 2020,and were divided into a study group and a control group using a random number table model;patients in the control group did not undergo genetic testing and FOLLOX4+PD-1 chemotherapy,while patients in the study group underwent TYMS,ERCC1,EGFR,and KRAS and VEGF gene expression levels test,and the sensitive treatment plan was determined based on the test results,and the clinical indexes were compared between the two groups.Results:By comparing the total effective rate,survival time,and time to disease progression of chemotherapy in the two groups,the study group has a significant advantage(P<0.05).Conclusion:The combination of chemotherapy and targeted therapy for advanced gastrointestinal tumor patients can improve the efficiency of chemotherapy and prolong the time of disease progression and survival,which is worthy of comprehensive promotion.

Detection of serum tumor markers in the diagnosis and treatment of patients with pancreatic cancer

BACKGROUND: Although a variety of tumor markers areavailable for diagnosis of pancreatic cancer, their sensitivityand specificity have not yet been ideal. The aims of thisstudy was to detect a panel of serum tumor markers and toevaluate their significance in the diagnosis and prognosis ofpancreatic cancer patients.METHODS: Eight serum tumor markers including AFP,CEA, CA-50, CA72-4, CA-125, CA153, CA19-9 and CA242were detected in 129 patients with pancreatic cancer by usingchemiluminescence immunoassay, immunofluorescence as-say and immunoradiometric assay, respectively. The levelsof these markers were compared in 99 patients with non-pancreatic malignant tumor, 63 patients with other benigndiseases, and 27 patients with pancreatic cancer after pan-createctomy.RESULTS: Among the 8 tumor markers, CA19-9, CA242,CA-50, and CA72-4 were more sensitive in the diagnosis ofpancreatic cancer. Parallel combined testing could increasethe diagnostic sensitivity to 89.2%, and serial combined exa-mination could increase the diagnostic specificity to 92.3%.The serum tumor markers levels were decreased significant-ly after radical tumor resection.CONCLUSIONS: Serum CA19-9, CA242, CA-50, andCA72-4 are the preferred tumor markers to be used in thediagnosis and follow-up of operated cases of pancreaticcancer. Testing of a panel of multiple serum tumor mark-ers may increase the sensitivity and specificity in the diag-nosis of pancreatic cancer.

Ecological Adaptability of New Hybrid Rapeseed Varieties in Sichuan Hilly Areas

[Objective] The aim was to explore rapeseed varieties adapting to local conditions, with optimal yielding capacity and growth period. [Method] The research performed analysis on yield, yielding components, and interaction effects in different groups and test sites based on hybrid rapeseeds in Mianyang during 2012-2015.[Conclusion] Mianyou 33, Mianyou 88 and Mianyou 309 showed insignificant differences in yield. The analysis of variance suggested that yield of Mianyou 309 was the highest and the variety was suitable to be planted in high erucic acid rapeseed bases. Mianyou 88 and Mianyou 33 are double-low varieties, characterized by high and stable yielding. [Conclusion] The research provides references for rapeseed production in hilly areas in Sichuan Province.

Analysis of Clinical Characteristics and Diagnostic Value of Fungal Serology in Patients with Invasive Candidiasis

Objective: To evaluate the diagnostic value of (1 - 3)-β-D glucan and mannan assay for invasive candidiasis. Methods: A retrospective study was conducted on 32 cases in the disease group (18 proven invasive candidiasis and 14 probable invasive candidiasis) and 48 cases in the control group. The subjects were recruited from January 2018 to March 2019 in Clinical Laboratory of Hainan General Hospital. All subjects were detected by (1 - 3)-β-D glucan and mannan assay. Results: The mean concentration of (1 - 3)-β-D glucan in the disease group was 97.45 (43.23, 224.35) pg/ml and it was significantly higher than the mean concentration of the control group which was 49.85(41.91, 56.07) pg/ml (P = 0.005). The mean concentration of mannan in the disease group and the control group were 161.36 (34.96, 224.49) pg/ml and 25.80 (25.00, 29.31) pg/ml, respectively, which were significantly different (P < 0.001). The sensitivity, specificity, positive predictive value and negative predictive value of (1 - 3)-β-D glucan assay were 59.38%, 89.58%, 79.17%, 76.79%, respectively. The sensitivity, specificity, positive predictive value and negative predictive value of mannan assay were 65.63%, 95.83%, 91.30%, 80.70%, respectively. The sensitivity, specificity, positive predictive value and negative predictive value of combination of two types of assays were 81.25%, 85.42%, 78.79% and 87.23%, respectively. Conclusions: Combination of (1 - 3)-β-D glucan and mannan assay can improve diagnostic specificity and it has essential clinical diagnostic value for invasive candidiasis.

Test Generation and Design-for-Testability Based on Acyclic Structure with Hold Registers

We present a method of test generation for acyclic sequential circuits with hold registers. A complete (100% fault efficiency) test sequence for an acyclic sequential circuit can be obtained by applying a combinational test generator to all the maximal time-expansion models (TEMs) of the circuit. We propose a class of acyclic sequential circuits for which the number of maximal TEMs is one, i.e, the maximum TEM exists. For a circuit in the class, test generation can be performed by using only the maximum TEM. The proposed class of sequential circuits with the maximum TEM properly includes several known classes of acyclic sequential circuits such as balanced structures and acyclic sequential circuits without hold registers for which test generation can be also performed by using a combinational test generator. Therefore, in general, the hardware overhead for partial scan based on the proposed structure is smaller than that based on balanced or acyclic sequential structure without hold registers.

COMBINATORIAL DESIGN APPROACHES FOR AUTOMATIC TEST GENERATION

The n-way combination testing is a specification-based testing criterion, which requires that for a system consisted of a few parameters, every combination of valid values of arbitrary n(n >_2) parameters be covered by at least one test. This letter proposed two different test generation algorithms based on combinatorial design for the n-way coverage criterion. The automatic test generators are implemented and some valuable empirical results are obtained.

Test Vector Optimization Using Pocofan-Poframe Partitionin

This paper presents an automated POCOFAN-POFRAME algorithm thatpartitions large combinational digital VLSI circuits for pseudo exhaustive testing. In thispaper, a simulation framework and partitioning technique are presented to guide VLSIcircuits to work under with fewer test vectors in order to reduce testing time and todevelop VLSI circuit designs. This framework utilizes two methods of partitioningPrimary Output Cone Fanout Partitioning (POCOFAN) and POFRAME partitioning todetermine number of test vectors in the circuit. The key role of partitioning is to identifyreconvergent fanout branch pairs and the optimal value of primary input node N andfanout F partitioning using I-PIFAN algorithm. The number of reconvergent fanout andits locations are critical for testing of VLSI circuits and design for testability. Hence, theirselection is crucial in order to optimize system performance and reliability. In the presentwork, the design constraints of the partitioned circuit considered for optimizationincludes critical path delay and test time. POCOFAN-POFRAME algorithm uses theparameters with optimal values of circuits maximum primary input cone size (N) andminimum fan-out value (F) to determine the number of test vectors, number of partitionsand its locations. The ISCAS’85 benchmark circuits have been successfully partitioned,the test results of C499 shows 45% reduction in the test vectors and the experimentalresults are compared with other partitioning methods, our algorithm makes fewer testvectors.

Testing High-Dimensional Nonparametric Behrens-Fisher Problem

For high-dimensional nonparametric Behrens-Fisher problem in which the data dimension is larger than the sample size,the authors propose two test statistics in which one is U-statistic Rankbased Test(URT)and another is Cauchy Combination Test(CCT).CCT is analogous to the maximumtype test,while URT takes into account the sum of squares of differences of ranked samples in different dimensions,which is free of shapes of distributions and robust to outliers.The asymptotic distribution of URT is derived and the closed form for calculating the statistical significance of CCT is given.Extensive simulation studies are conducted to evaluate the finite sample power performance of the statistics by comparing with the existing method.The simulation results show that our URT is robust and powerful method,meanwhile,its practicability and effectiveness can be illustrated by an application to the gene expression data.

Pseudo-Random Test Generation for Large Combinational Circuits

In this paper,a simulation system of pseudo-random testing is described first to investigate the characteristics of pseudo-random testing.Several interesting experimental results are obtained.It is found out that initial states of pseudo-random sequences have little effect on fault coverage.Fixed connection between LFSR outputs and circuit inputs in which the number of LFSR stages m is less than the number of circuit inputs n leads to low fault coverage,and the fault coverage is reduced as m decreases.The local unrandomness of pseudo-random sequences is exposed clearly.Generally,when an LFSR is employed as a pseudo-random generator,there are at least as many LFSR stages as circuit inputs.However,for large circuits under test with hundreds of inputs,there are drawbacks of using an LFSR with hundreds of stages.In the paper,a new design for a pseudo-random pattern generator is proposed in which m<n.The relationship between test length and the number of LFSR stages is discussed in order to obtain necessary,fault coverage.It is shown that the design cannot only save LFSR hardware but also reduce test length without loss of fault coverage,and is easy to implement. The experimental results are provided for the 10 Benchmark Circuits to show the effectiveness of the generator.

A Complete Critical Path Algorithm for Test Generation of Combinational Circuits

It is known that critical path test generation method is not a complete algorithm for combinational circuits with reconvergent-fanout.In order to make it a complete algorithm,we put forward a reconvergent-fanout- oriented technique,the principal critical path algorithm,propagating the critical value back to primary inputs along a single path,the principal critical path,and allowing multiple path sensitization if needed.Relationship among test patterns is also discussed to accelerate test generation.