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The effects of the moisture content, density, and striking direction of a hammer on the vibrational characteristics, i.e., the fundamental frequency and dynamic modulus of elasticity, of four wood species, i.e., poplar (Populus tomentosa), mahogany (Swietenia mahagoni), beech (Fagus orientalis), and ash (Fraxinus excelsior), commonly used in wood products were investigated, aiming to provide basic evidence for the nondestructive testing of wood materials. The results showed that the effect of the wood species on the fundamental frequency, dynamic modulus of elasticity, and static modulus of elasticity was statistically significant. The dynamic moduli of elasticity of the four wood species were higher than the corresponding static moduli of elasticity. The effect of the striking direction on the dynamic modulus of elasticity was not significant, indicating that no matter where the hammer struck, i.e., radial and tangential surfaces, the fundamental frequency was essentially constant. Negative relationships were found between the fundamental frequency and the density and moisture when the data of the four wood species were viewed as a population sample. The vibrational characteristics of each wood species varied, which can be applied to the nondestructive testing of wood.

The effect of impregnation treatment of low molecular weight phenol formaldehyde (MWPF) resin on the bolt-bearing yield strength (BBYS) of a three-layered cross-laminated timber (CLT) composed of two face layers of southern pine (Pinus taeda) and one core layer of sweetgum (Liquidambar styraciflua) was investigated together with two additional factors of material type and loading direction. Experimental results indicated that the amount of low MWPF resins penetrating into sweetgum was more than the ones into southern pine. Sweetgum had more uniform distribution of low MWPF resins penetrating longitudinally than southern pine. Impregnation treatment using a low MWPF resin at a concentration of 20% can enhance the BBYS of three-layered CLTs with a 60% increase. The BBYS of a core layer material in three-layered CLTs can significantly alter the overall BBYS of the three-layered CLTs.

WenGang Hu, YaJun Song, Xiao Zhong, JiaYu Feng, PingXian Wang, ChiBing Huang Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, People’s Republic of China Abstract: Effective doctor–patient communication is essential for establishing a successful doctor–patient relationship and implementing high-quality health care. In this study, a novel urinary system-simulating physical model was designed and fabricated, and its content validity for improving doctor–patient communication was examined by conducting a randomized controlled trial in which this system was compared with photographs. A total of 240 inpatients were randomly selected and assigned to six doctors for treatment. After primary diagnosis and treatment had been determined, these patients were randomly divided into the experimental group and the control group. Patients in the experimental group participated in model-based doctor–patient communication, whereas control group patients received picture-based communication. Within 30 min after this communication, a Demographic Information Survey Scale and a Medical Interview Satisfaction Scale (MISS) were distributed to investigate patients’ demographic characteristics and their assessments of total satisfaction, distress relief, communication comfort, rapport, and compliance intent. The study results demonstrated that the individual groups were comparable with respect to demographic variables but that relative to patients in the picture-based communication group, patients in the model-based communication group had significantly higher total satisfaction scores and higher ratings for distress relief, communication comfort, rapport, and compliance intent. These results indicate that the physical model is more effective than the pictures at improving doctor–patient communication and patient outcomes. The application of the physical model in doctor–patient communication is helpful and valuable and therefore merits widespread clinical popularization. Keywords: doctor–patient communication, doctor–patient relationship, model, urology

The roller cone bit is one of the most important rock breaking tools used in the oil–gas drilling industry. Its performance directly influences the drilling quality, efficiency and cost. As the world’s oil–gas resource exploration continuously developed, the drilling speed accelerated, accelerating the failure speed of the bearing. The roller cone bit’s service life was almost directly dependent on that of the bearing. In this paper, a bearing failure analysis, and an experimental research on the surface strengthening technology of the bearing with field applications etc. were carried out. The results showed that the bearing’s main failure modes included fracture, plastic deformation and wear. The main reasons were overload and uneven distribution of the load; elevated temperature due to friction caused property and structure change in material; wear increased the fit clearance between the bearing and the cone, increasing dynamic impact load etc. The bearing surface strengthening technology, employing plasma-arc surfacing DH-60 wear resistance alloy, could prolong the service life of the bearing. Experimental research and field tests showed that the wear and impact resistance of the enhanced bearing increased by 30% with an increased service life of 12% on average.

The optical elements’ maladjustment is a potential threaten in optical systems, thus, the transmission feature of laser beams passing through a misaligned optical system is widely studied. By using approximate expansion of circle diaphragm and generalized Huygens-Fresnel diffraction formula, a universal analytic expression is deduced for the flat-topped multi-Gaussian beams passing through a misaligned optical system with two-lens and two-diaphragm. The study on the propagating property of fundamental-mode Gaussian beams and a flat-topped multi-Gaussian beam is carried out accordingly. The expansion of complex Gauss function of misaligned optical circle diaphragm is given, as well as a group of new parameter values of the expansion of complex Gauss function. By using the new parameter values, the influence of disadjust parameters on output intensity distribution is analyzed numerically. The result shows that the diaphragms’ offset can make the beams offset or covered, and the second diaphragm influences more; the angle deflection of diaphragms can make light beams compressed in the deflection direction, and the first diaphragm influences more; the offset of the first lens can weaken light intensity in the same direction of the lens offset, and the offset of the second lens can weaken light intensity in the opposite direction of the lens offset; the angle deflection of the first lens can make light beams move to the opposite direction, and the angle deflection of the second lens has no influence; when all the diaphragms and the lenses are disadjust, the angle deflection of the first lens has a vital influence to the output intensity distribution.

Single-channel triple-band color night vision system is able to gain low-light color imagery. The core design idea of one-channel triple-band color night vision system is increasing a scanner than traditional low-light night vision system in the front of the image intensifier. The scanner is consisted of several filters which is used for dividing the emitted light or reflected light of the aim into three parts, R, G and B. Each part is taken a frame image respectively and then fused three frames into color imagery by Color Mapping Guidelines. The addition of filters makes the SNR of each frame image decreases, it means that images detail loss and gray value is low. To overcome this difficult, on the basis of three frame images fusion, a frame image of all band is added to fusion. Experimental results show that fused image which is fused by R, G, B and all band improve image brightness and detail information obviously through calculating the variance and entropy. This fused method is more conducive to the human eye.

A compact simultaneous actively Q -switched and mode-locked eye-safe Raman laser employing Nd:KLu(WO 4 ) 2 as gain medium and BaWO 4 as Raman medium with high mode-locking repetition-rate is demonstrated. The picosecond first Stokes at 1549 nm based on the fundamental laser emission at 1355 nm is realized. With an absorbed pump power of 14.6 W and pulse repetition frequency of 20 kHz, a maximum output power of 1.4 W with the mode-locking pulse repetition rate of 1.6 GHz is obtained; the corresponding mode-locking pulse width is approximate 28 ps.

An optical time domain reflectometer(OTDR) using appropriate encoding light pulses as probe signals can has much better performance than conventional OTDR , for example, improve the measure dynamic range but not reduce the resolution, reduce the required measurement time and so on. This paper present application study of one zero correlation window complementary coded sequence in OTDR, discussed the theoretical foundation of this method and introduced the method to change bipolar codes to unipolar codes, shown the Matlab simulation results at last.

This paper introduces some new methods for measuring parameters of the telescope system with CCD device such as OTF, parallax, diopter and so on. It doesn’t need man’s subjective judgment. The computer accomplishes the assignment to display, print and save the results automatically. So, these methods have some advantages: high accuracy, digital display, and autoimmunization. Basing on the mentioned theory analysis in the paper, we have realized the digitization checkout of a lot of parameters on same instrument.

The principle of determining passive incident laser beam's space direction by use of linear array CCD deice and structural design of the system are analyzed theory and experiment show passive incident laser beam's space direction can be determined accurately and quickly.