Design and Fabrication of Pneumatically Actuated Valveless Pumps

In this study, a valveless pump was successfully designed and fabricated for the purpose of medium transportation. Different from traditional pumps, the newly designed pump utilizes an actuated or a deflected membrane, and it serves as the function of a check valve at the same time. For achieving the valveless property, an inlet or outlet port positioned in an upper- or lower-layer thin membrane was designed to be connected to an entrance or exit channel. Theoretical analysis and numerical simulation were conducted simultaneously to investigate the large deformation characteristics of the membranes and to determine the proper location of the inlet or outlet port on the proposed pump. Then, the valveless pump was fabricated on the basis of the proposed design. In the experiment, the maximum flow rate of the proposed pump exceeded 12.47 mL/min at a driving frequency of 5.0 Hz and driving pressure of 68.95 kPa.

Development of a virtual reality simulatorreplacing the check valve on christmas tree

The article describes the stages of the process of creating a virtual reality simulator using the example of a standard operating procedure for replacing a check valve on a Christmas tree. A brief overview of the Christmas tree arrangement and an analysis of the stages of the check valve replacement are described. A short algorithm has been developed based on 11 out of 16 implemented stages. The choice of hardware platform and software is substantiated. Using the Christmas tree as an example, the processes of creating a three-dimensional model and unfolding textures in the three-dimensional editor 3ds Max, creating color maps, reflection and texture normals in the graphical editor Substance Painter are described. The process of creating a landscape in the Unity3D environment is described. Oculus Integration and VR TK assets were used in the development of the main scripts.

Development of a virtual reality simulator replacingthe check valve on christmas tree

The article describes the process of designing and creating a software environment that allows in automatic mode to create a realistic landscape. A review of existing approaches to landscape generation is carried out, which have a set of disadvantages taken into account when developing a software environment. A diagram of components and main classes is described. The developed subroutine that implements the polygon mesh generation algorithm provides an interface for creating and editing a mesh of hexagons on a plane, used for simplified work with biomes, as well as detailing the boundaries of polygons to give the landscape elements of randomness and, as a result, realism. The process uses the Diamond Square noise generation algorithm. The docking algorithm is designed to reduce the gaps between the heights of different biomes. The erosion algorithm uses particles generated on a height mapto carry soil particles in accordance with physical laws. The user interface of the application and the results of the algorithms are presented.

Sliding Dispersion Entropy-Based Fault State Detection for Diaphragm Pump Parts

Aiming at the disadvantages of low trend, poor characterization performance, and poor anti-noise performance of traditional degradation features such as dispersion entropy (DE), a fault detection method based on sliding dispersion entropy (SDE) is proposed. Firstly, a sliding window is added to the signal before extracting the DE feature, and the root mean square of the signal inside the sliding window is used to replace the signal in the window to realize down sampling, which enhances the trend of DE. Secondly, the hyperbolic tangent sigmoid function (TANSIG) is introduced to map the signals to different categories when extracting the DE feature, which is more in line with the signal distribution of mechanical parts and the monotonicity of the degradation feature is improved. For noisy signal, the introduction of locally weighted scatterplot smoothing (LOWESS) can remove the burrs and fluctuations of the SDE curve, and the anti-noise performance of SDE is improved. Finally, the SDE state warning line is constructed based on the 2σ criterion, which can determine the fault warning point in time and effectively. The state detection results of bearing and check valve show that the proposed SDE improves the trend, monotonicity, and robustness of the state tracking curve, and provides a new method for fault state detection of mechanical parts.

A pneumatocele observed in the thoracic cavity after bronchoalveolar lavage

A 76-year-old man was admitted to the respiratory medicine department with 5 days of a non-productive cough and exertional dyspnea. A computed tomography revealed multiple mild patchy consolidations in both lungs (Figure 1). Despite antibiotic therapy, there was poor improvement in laboratory and radiological parameters. A bronchoscopy was performed on day 5. The bronchoscopy was wedged in left B5 and a bronchoalveolar lavage (BAL) was performed. After the BAL, we noticed a fistula in the depth of left B5 and saw a structure like a pleural cavity in the back of the fistula (Figure 2). We diagnosed the patient’s condition as pneumatocele (PC). BAL showed 46% lymphocytes and the CD4/8 ratio as 3:7. These findings suggested cryptogenic organizing pneumonia (COP). It took 3 weeks for the PC to improve. Bilateral multiple consolidations improved after the administration of a steroid (PSL 0.5 mg/kg). PCs can occur in infections, chest trauma, barotrauma from mechanical ventilation, and bronchial interventions [1,2]. The mechanism of PC formation is closely related to that of a check valve. The check valve may be composed of exudate from inflammation and the destroyed wall of the respiratory tract [3]. In this case, it was considered that the wedged bronchoscopy and collapsed bronchial wall became the check-valve. PCs can be a severe condition including tension pneumothorax, bronchopleural fistula, and secondary infections [4]. In our case, as we were concerned about new complications due to the PC we did not prescribe a steroid for COP until the PC had improved. To our knowledge, no papers have reported internal observations of PC. We herein report the first case of PC observed in the thoracic cavity after BAL.

A Power Take-Off (PTO) for Wave Energy Converters Based on the Hybrid Hydraulic-Electric Architecture (HHEA)

Wave energy is a promising renewable energy resource for coastal regions around the world, but is not yet an economically competitive source of electricity. More effective power take-off (PTO) designs would help to make wave power a feasible and clean source of energy. To do this, PTOs need to: i) enable controlled actuation, ii) convert absorbed energy into electricity efficiently, and iii) have minimal manufacturing costs. We propose a new PTO architecture that can exert arbitrary control loads on the WEC to maximize energy capture, enabling the downsizing of expensive electrical components while maintaining high efficiency. Our PTO design is based upon a hybrid hydraulic-electric architecture (HHEA). This paper compares the performance of the HHEA PTO against two other PTO designs: 1) a baseline PTO consisting of a system of rectifying check valves and accumulators, and 2) a PTO consisting of an electro-hydraulic actuator (EHA). The HHEA PTO is shown to produce much more power than the check valve PTO and the EHA PTO. Also, the required electric generator sizes for the HHEA are smaller than that of the EHA PTO. The reduced size of these components allows for a WEC which is less expensive to manufacture.