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Thermoplastic components are gaining more and more attention due to their advantages which include high specific strength, high toughness, and low manufacturing costs. Despite the fast development of such materials in engineering applications, the major challenge for the wider use of thermoplastic components is the diverse mechanical properties that are caused by uncertain factors during the molding process. In this paper, the effects of processing parameters on the mechanical properties of PEEK plates by hot compression molding are systematically investigated, including the temperature, pressure, and compression time. It was found that both temperature and time can sensitively change the mechanical properties; however, a pressure larger than 1.5 MPa showed a limited impact on the mechanical behaviors of PEEK plates. The optimal process parameters include a hot compression temperature of 400 °C, a compression time of 30 min, and a pressure of 2.5 MPa.

Tanzania suffers problems of cost and time overruns in the construction business. Many factors are contributing to the cost and time overruns in Tanzania construction projects. There are many publications in different countries about cost and time overruns in construction projects, these publications show that the problem of overruns varies from country to country. This variation gives the idea that even in Tanzania there is a need for researches concerning cost and time overruns. Some researchers worked on the problems of cost and time issues in Tanzania but narrowing only on the identification of factors. This study used the survey to identify the frequent factors in Tanzania and the quantitative assessment of the completed projects to quantify the influence of each factor contributing to cost and time overruns. To come up with the results shows the extent influence of each factor in overruns in expected in this research and it will be the key pillar in construction management to fight against overruns.

Multi-source information fusion diagnosis is usually more reliable than fault diagnosis with a single source employed. However, fusion results may be absurd when fusing highly conflicting information. To address this problem, the Dempster–Shafer (DS) evidence theory is updated by weighting each piece of evidence according to the corresponding contribution to the decision, and a novel fault diagnosis method based on multi-source conflict information fusion is proposed. First, the basic probability assignment of evidence corresponding to the sensor information is given by introducing the feature parameters of electromyographic signals and using the back-propagation neural network. Then, the importance of each piece of evidence is determined by solving the difference degree and exclusion degree among the evidence, and the evidence is assigned weights according to the degree of importance of each piece of evidence in the fusion decision-making process. Next, the weighted evidence is combined for making decisions and further diagnosis after weighted averaging of the evidence with different weights. Finally, the performance of the proposed method is assessed using receiver operating characteristic (ROC) curves. The experimental results show that the areas under the ROC curves for the proposed method are 0.3229, 0.0729 and 0.9271 higher than those of the traditional DS method, Murphy’s method and Yager’s method, respectively, which proves that the proposed method has better diagnostic performance and reliability.

In view of the complexity and low accuracy of existing fault diagnosis methods for transmission network, this paper proposes a novel transmission network fault diagnosis method combining simplified Bayesian network and fault decision table. First, using the information from Supervisory Control and Data Acquisition (SCADA) system, there develop a fault area identification method, which utilizes circuit breaker (CB) information to isolate the components to build a fault area. In fault area, there creates the simplified Bayesian network to associate components with CBs. Further, the paper proposes a calculation method to calculate the fault probability of components in fault area, which is able to determine the suspicious component set. According to the sequence of relay actions, a fault decision table for the suspicious component set can be established. Finally, the fault condition of components, CBs and protection devices are diagnosed by comparing the local fault decision table. The above method greatly simplifies the complexity of Bayesian network, and the test results show that the speed and accuracy of its fault diagnosis have been significantly improved.

The setting of traditional distance zone-II protection is very complicated, which is due to the difficulty in determining the operating mode and its branch coefficient under the cooperation of multiple lines. So this paper proposes a novel simplified setting method of distance backup protection. This method simplifies the calculation of setting value and accelerates the action time of protection device, which makes the distance zone-II protection only cooperate with the protection of zone-I of local line and only consider the sensitivity coefficient. To further ensure the selectivity of relay protection, the paper develops a fault line detection to match the above method based on random matrix spectral analysis, whose matrix formed by the measured lines current. Then the paper designs a feasible simplified setting process of distance zone-II backup protection by integrating the above methods. Finally, the example analysis shows the simplified setting method of distance backup protection can ensure the selectivity of relay protection, correctly identify the faulty line and speed up the action time.

Fluoroquinolones (FQs) present in water environments pose threats to aquatic organisms. The concentration of FQs adsorbed onto sediments is generally higher than that in water. Here, we studied the toxicities of two FQ antibiotics, norfloxacin (NOR) and ofloxacin (OFL), on the snail Bellamya aeruginosa, an adaptable benthic animal. For this, we performed acute toxicity experiments on young snails and sub-chronic exposure experiments on adult snails by exposure to the FQs for 1–28 days. The 96 h median effective concentrations showed that NOR toxicity was higher than OFL toxicity, although both NOR and OFL were low-toxicity substances (EC50 > 100 mg L−1). Four concentrations were used in the sub-chronic exposure experiments. Results of the measurement of bioconcentration factors (BCF) showed that OFL accumulation was higher than NOR accumulation in snail tissues. During the depuration period (28–49 days), at low concentrations (2 and 20 μg L−1), both FQs required at least 7 days to reach the maximum residue limit (50 μg kg−1). Conversely, at high concentrations (200 and 2000 μg L−1), 14 days (NOR) and 21 days (OFL) were required. Our results could facilitate management of the environmental risks of antibiotics and conservation of aquatic animals.

Tiny but highly efficient, a light emitting diode (LED) can power a therapy device, such as a phototherapy device, and, at the same time, decrease the device’s size requirements. In this study, a LED phototherapy device was designed to investigate the possible impact on wound healing using a mouse model and a cell line exposed to red and blue light. To enhance wound phototherapy, a gelatin sponge was fabricated. Results showed that the red and blue lights promoted cell growth and wound healing, while the blue light with a gelatin sponge protected the wound from infection in the early stages of wound healing. The LED phototherapy device combined with the gelatin sponge, therefore, has potential significance in clinical application for wound healing.

Early diagnosis of prostate cancer (PCa) is always a great challenge in clinical practice, especially in distinguishing benign prostatic hyperplasia (BPH) from early cancer, due to the high similarity in pathology from the prostate‐specific antigen (PSA) test and radiological detection. The conventional diagnostic methods are often less efficient in specificity and accuracy, leading to quite a few unnecessary biopsies. This work establishes a noninvasive diagnostic method for PCa by investigating urine samples using Raman spectroscopy and convolutional neural network (CNN) algorithm. The results of urine Raman spectra show the intensities of characteristic peaks for lipids, nucleic acids, and some amino acids are distinguishable between PCa and BPH, suggesting an abnormal metabolism caused by PCa, which can be detected by Raman spectroscopy. These data are then used to train an intelligent diagnostic model with CNN algorithm. The cross‐validation results show the mean diagnostic accuracy, sensitivity, and specificity for PCa are 74.95%, 77.32%, and 72.46%, respectively. This noninvasive diagnostic method is a promising method for the early diagnosis of PCa, and the idea of using urine Raman spectroscopy with deep learning techniques for diagnosing PCa provides a reference for the application of artificial intelligence in the field of clinical medicine research.

Hypoxia is a disorder in which the tissues are not oxygenated adequately. The lack of oxygen may cause irreversible damage to the major organs such as the brain, heart and lungs. In severe cases, coma, seizures, and death may happen. In addition to the routine medication, acupuncture treatment has been applied as a complementary treatment to counter hypoxia. In this paper, the optical fiber acupuncture needle was fabricated using the optical fiber imbedding into the metal capillary tube with needle tip, therefore made it easy to insert into the body for the laser treatment. The laser optical fiber needle treatment to the ST36 acupoint conducted with the laser irradiation intra body. The normobaric hypoxia tolerance test results in mice show that the optical fiber needle treatment to the ST36 acupoint with laser acupuncture appears to improve the tolerance to hypoxia. The mice treated with laser acupuncture expressed high level of IL-1[Formula: see text] in serum. Our results suggest that laser optical fiber needle acupuncture may serve as a potential treatment for hypoxia.