Design of a New Device for Household Cleaning

2012 ◽  
Vol 201-202 ◽  
pp. 711-714
Author(s):  
Wei Wang ◽  
Guo Fu Li ◽  
Jun Chen ◽  
Ji Dong Ma

The characteristics of traditional vacuum cleaner and automatic cleaning robot are analyzed in the paper. A new device for household cleaning is designed. The device combines leaning mechanism with suction mechanism. It could work only by pushing the cleaning machine. In its working process, the cleaning mechanism cleans larger litters first, and then the acceleration mechanism drives the impeller rotating at a high speed, and thus produces negative pressure to inhale the remaining dust. The device could improve cleaning efficiency. As the dust suction mechanism only needs to inhale dust, the force could be smaller .It will saves power and reduces the noise generated by the vacuum part at the same time.

Author(s):  
Peter Scott

The vacuum cleaner was an archetypal new economy product of the early twentieth century. It offered both major time savings and qualitative advantages over previous household cleaning methods—the brush, broom, and manual carpet sweeper—and was sold in a novel way (by household demonstration). The direct sales techniques pioneered by vacuum manufacturers in the United States were to have a profound impact on the way vacuums were sold in Britain, and globally. Yet by 1939 their household diffusion was relatively slow compared to refrigerators or washing machines. This chapter explores why the industry evolved a structure based on high prices, high cost distribution methods (door-to-door sales), and a strong emphasis on non-price competition, based on differentiation through features. It also shows how door-to-door selling eventually came to constitute both a key firm-level competitive advantage and a substantial industry-level constraint on product diffusion.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Hitesh Agarwal ◽  
Bernat Terrés ◽  
Lorenzo Orsini ◽  
Alberto Montanaro ◽  
Vito Sorianello ◽  
...  

AbstractElectro-absorption (EA) waveguide-coupled modulators are essential building blocks for on-chip optical communications. Compared to state-of-the-art silicon (Si) devices, graphene-based EA modulators promise smaller footprints, larger temperature stability, cost-effective integration and high speeds. However, combining high speed and large modulation efficiencies in a single graphene-based device has remained elusive so far. In this work, we overcome this fundamental trade-off by demonstrating the 2D-3D dielectric integration in a high-quality encapsulated graphene device. We integrated hafnium oxide (HfO2) and two-dimensional hexagonal boron nitride (hBN) within the insulating section of a double-layer (DL) graphene EA modulator. This combination of materials allows for a high-quality modulator device with high performances: a ~39 GHz bandwidth (BW) with a three-fold increase in modulation efficiency compared to previously reported high-speed modulators. This 2D-3D dielectric integration paves the way to a plethora of electronic and opto-electronic devices with enhanced performance and stability, while expanding the freedom for new device designs.


2005 ◽  
Author(s):  
Matthew J. Mason ◽  
Chirag S. Shah ◽  
Muralikrishna Maddali ◽  
King H. Yang ◽  
Warren N. Hardy ◽  
...  

Author(s):  
Gorka Azkune ◽  
Mikel Astiz ◽  
Urko Esnaola ◽  
Unai Antero ◽  
Jose Vicente Sogorb ◽  
...  

2003 ◽  
Vol 1 (1) ◽  
pp. 3-14 ◽  
Author(s):  
Mark W. LeChevallier ◽  
Richard W. Gullick ◽  
Mohammad R. Karim ◽  
Melinda Friedman ◽  
James E. Funk

The potential for public health risks associated with intrusion of contaminants into water supply distribution systems resulting from transient low or negative pressures is assessed. It is shown that transient pressure events occur in distribution systems; that during these negative pressure events pipeline leaks provide a potential portal for entry of groundwater into treated drinking water; and that faecal indicators and culturable human viruses are present in the soil and water exterior to the distribution system. To date, all observed negative pressure events have been related to power outages or other pump shutdowns. Although there are insufficient data to indicate whether pressure transients are a substantial source of risk to water quality in the distribution system, mitigation techniques can be implemented, principally the maintenance of an effective disinfectant residual throughout the distribution system, leak control, redesign of air relief venting, and more rigorous application of existing engineering standards. Use of high-speed pressure data loggers and surge modelling may have some merit, but more research is needed.


Author(s):  
Yoichiro Fukuchi ◽  
Tomoki Kondo ◽  
Keita Ando

Abstract In semiconductor industry, liquid jet cleaning plays an important role because of its high cleaning efficiency and low environmental load. However, its cleaning mechanism is not revealed in detail because the experimental observation of high-speed and sub-micron droplets is challenging. Furthermore, higher impact velocity may give rise to surface erosion due to water-hammer shock loading from the impingement. To study cleaning mechanisms and surface erosion, numerical simulation of droplet impingement accounting for both viscosity and compressibility is an effective approach. In the previous study, wall-shear-flow generation has evaluated from the simulation of high-speed single droplet impingement. To evaluate more practical model of jet cleaning application, simulation of two droplets simplifying mono-dispersed splay of droplet train is favorable. Here, we numerically simulated impingement of two droplets, which allows for evaluating water-hammer pressure and wall shear stress. We consider the case of two water droplets (200 μm in diameter) that collides continuously, at speed 50 m/s, at the inter-droplet distance from 250 to 400 μm, with a no-slip rigid wall covered with a water layer (100 μm in thickness). The simulation is based on compressible Navier-Stokes equations for axisymmetric flow and the mixture of two components appears in numerically diffusion interface expressed by the volume average and advection equation. The simulation is solved by finite-volume WENO scheme that can capture both shock waves and material interface. In our simulation, the impingement of second droplet impingement gain higher shear stress than the single droplet impingement. At the case that the inter-droplet distance is 300 μm, maximum shear stress is 30.22 kPa (at the second droplet impingement), which is much larger than at the first droplet impingement (8.42 kPa). This result indicates how the second droplet impingement make wall shear flow induced by first droplet impingement stronger. From the parameter study of the inter-droplet distance, we can say that wall shear stress gets stronger as water layer thickness decreases. Furthermore, the maximum wall pressure is 1.96 MPa at the second droplet impingement, which is larger than at the first droplet impingement (1.46 MPa). From this study, the evaluation of surface erosion caused by jet cleaning is expected. The simulation suggests that multiple droplets impingement continuously may gain higher cleaning efficiency, which will give us a fundamental insight into liquid jet cleaning technologies. For further study, simulation of water column impingement and comparing the result of impingement of two droplets are expected.


Complexity ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-17
Author(s):  
He-xuan Hu ◽  
Wan-xin Lei ◽  
Ye Zhang

With the world development of high-speed railways and increasing speeds, aerodynamic forces and moments acting on trains have been increased further, making trains stay at a “floated” state. Under a strong crosswind, the aerodynamic performance of a train on the embankment is greatly deteriorated; lift force and horizontal force borne by trains will be increased quickly; trains may suffer derailing or overturning more easily compared with the flat ground; train derailing will take place when the case is serious. All of these phenomena have brought risks to people’s life and properties. Hence, the paper establishes an aerodynamic model about a high-speed train passing an air barrier, computes aerodynamic forces and moments, and analyzes pulsating pressures on the train surface as well as those of unsteady flow fields around the train. Computational results indicate that when the train passed the embankment air barrier, the head wave of air pressure full wave is more than the tail wave; the absolute value of negative wave is more than that of the positive wave, which is more obvious in the head train. When the train is passing the air barrier, pressure pulsation values at head train points are more than those at other points, while pressure changes most violently at the train bottom, and pressure values close to the air barrier are more than those points far from the air barrier. Pressure values at the cross section 1 were larger than those of other points. Pressure values at measurement points of the tail train ranked the second place, with the maximum negative pressure of 1253 Pa. Pressure change amplitudes and maximum negative pressure on the train surface are increased quickly, while pressure peak values on the high-speed train surface are in direct ratio to the running speed. With the increased speed of the high-speed train, when it is running in the embankment air barrier, the aerodynamic force and moment borne by each train body are increased sharply, while the head train suffers the most obvious influences of aerodynamic effects.


2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Kouki Imaoka ◽  
Takuya Yano ◽  
Yasuhiro Choda ◽  
Ko Oshita ◽  
Yuma Tani ◽  
...  

Background. The practice of leaving the abdomen open after an emergency laparotomy has gained increasing popularity recently. Negative pressure wound therapy (NPWT) is known as an effective technique in the management of an open abdomen (OA). A new device, the ABThera™ Open Abdomen Negative Pressure Therapy System (KCI USA, San Antonio, TX, USA), was specifically designed to achieve a temporary abdominal closure (TAC) in the management of an OA. This study was aimed at presenting a successful experience of treating a case of abdominal wall necrosis caused by a perforated ascending colon using the ABThera System. Case Presentation. A 66-year-old man was admitted to our hospital with complaints of severe pain in the abdomen. On admission, abdominal contrast-enhanced computed tomography (CT) showed fluid collection, an air pocket in the subcutaneous fat layer of the abdominal wall, and edematous changes in the adipose tissue in the peritoneum and abdominal wall. Based on a diagnosis of peritonitis resulting from a perforated ascending colon, emergency surgery was performed. A right hemicolectomy, ileostomy construction, and debridement of the necrotic tissues were performed. However, necrotizing fasciitis rapidly spread; therefore, more necrotic tissue was debrided in a second operation. The abdominal wall defect was left open, and the ABThera System was used in the management of the OA; this device promoted wound healing. A reduction was observed in the size of the open wound with visible granulation tissue. The defect was finally covered with a mesh split-thickness skin graft and anterolateral thigh flap. Conclusions. In the management of a case of a massive wound with infection, it can be of great benefit to treat the wound with NPWT initially to decrease its size. The ABThera System could facilitate early and safe management of an OA by surgeons.


2010 ◽  
Vol 97-101 ◽  
pp. 3565-3570
Author(s):  
Yan Mei Meng ◽  
Zhen Dong ◽  
Fu Ning Lu ◽  
Shang Ping Li ◽  
Kai Xu

The cleaning element is not only the key part of the sugarcane harvester, but it is also the bottleneck of the development within the whole stalk of the sugarcane harvester. In this paper, it will theoretically elaborate on the structural forces that act on the spiraled and brushed shape cleaning elements during the process of the sugarcane cleaning. The paper also elaborates on the combined rigidity of elements in different arrangement installations and the maximum stress that acts on its roots. In addition to this,the FEA (Finite Element Analysis) software-ANSYS is used to analyze the structural force, the maximum stress, and the air resistance that is generated during the working process. The results of the analysis have been validated by experimentations. The experimental results indicate that, with the proper spiral angle cleaning element installed, it can both enhance the cleaning efficiency and reduce the maximum stress and the air resistance. Accordingly, it can improve the cleaning quality, prolong the working life of the cleaning element, and reduce the idling power waste of the cleaning device.


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