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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Development of a self returning single acting diaphragm pump

Gunatilleke, N. N. January 1987 (has links)
No description available.
12

High performance repair materials in hydraulic structures and machines

Davoodi, Mehdi January 1998 (has links)
No description available.
13

The unusual transhydrogenase of Entamoeba histolytica

Weston, Christopher John January 2002 (has links)
No description available.
14

Junia : Comfort in milk expression

Wansch, Aaron January 2015 (has links)
This report describes the project background, design process plus the final result of my MFA degree thesis in Advanced Product Design at Umeå Institute of Design. A breast pump is generally a mechanical or electrical suction device for withdrawing milk from the breast of a lactating woman. Even though the first pumps were patented in the mid-19th century as medical devices for in-hospital use, breast pumps as widely available consumer products have only been around for a little more than 20 years. Existing breast pumps do not address functional as well as emotional needs of many mothers and there is great potential for improvements and innovative solutions to transform pumping into a more enjoyable and positively associated experience. The main purpose of this project is to rethink the way breast pumps are currently used in order to push the boundaries, and come up with a forward-looking, conceptual design solution as a final result. This human-centered design project was carried out in close collaboration with various experts in the areas of pediatrics, breastfeeding and lactation counselling. Moreover this project was done in cooperation with leading design and innovation consulting firm IDEO. San Francisco basted design director Thomas Overthun provided mentoring throughout the design process. Regular check-in calls and feedback sessions were set up throughout the project to discuss project milestones. Anders Smith, an experienced industrial designer from Denmark, closely followed throughout the project as an external design tutor at Umeå Institute of Design. Several tutoring sessions were held on a regular basis. Continuous involvement of experts and external project advisors helped to make sure that the project remains valid and provided a great source for relevant insights, expert knowledge and professional feedback. "Being able to develop an impactful and forward-looking design solution that can encourage positive change both on an individual and societal level has been my main motivation to tackle this design challenge".
15

Simulator för värmepump / Simulator for heat pump

Veseli, Kushtrim, Persson, Johan January 2017 (has links)
The report describes the project carried out for EasyServ, whose business is based on the monitoring and diagnosis of heat pumps. Their desire for the project was to develop a more efficient test system that makes it possible to easily simulate a heat pump behavior. The purpose of this was to enable more efficient tests with better accuracy for EasyServs product. This simplifies the quality assurance of the software for their product. The main problems the project were facing was how the test system should be designed and how the simulation of the heat pump's temperature sensors would be to mimic a heat pump. Another question mark was which communication interface was best suited for the test system. The method for constructing the test system was based on the use of the simulation technology Hardware-in-the-loop (HIL). The project was thus divided into subsystems Electronics Design and Programming. In Electronic design the decisions regarding the design were taken and the construction of the test system was made. The Programming subsystem deals with the development of the simulation program. The result was a test system consisting of a Raspberry Pi and a manufactured I/O board, where communication takes place through I²C. The I/O board has eight digital potentiometers which are used to simulate the heat pump’s temperature sensors. The simulation program developed in Raspberry Pi uses Python as programming language. The conclusion is that the project's test system provides a good basis for EasyServ to test their diagnostic tool in a simple way. A potential and desirable development that makes the test system even more useful for EasyServ would be to feedback the compressor signal.
16

Ventajas técnico económicas del shotcrete reforzado con fibras de acero comparado con el sostenimiento estructural, en labores mineras de tipo de roca IVA – IVB, según RMR en la unidad minera Carahuacra, E.U.A. Yauli, Volcan Compañía Minera S.A.A.

De la Cruz Coronel, John Pool 12 December 2018 (has links)
Actualmente, el shotcrete es un elemento de sostenimiento usado cada vez con mayor frecuencia en la minería subterránea, Volcan Compañía Minera S.A.A. no ajeno a ello, aplica la tecnología de concreto para generar una adecuada estabilización del macizo rocoso; sin embargo, cuando este es de baja calidad (roca tipo IV A – IV B) según RMR, obliga a incrementar su dimensionamiento (sostenimiento estructural) para garantizar la estabilidad de la labor, dilatando el tiempo de instalación del sostenimiento y el ciclo de minado, generando un incremento en el costo del mismo.
17

A study of Excitation dynamics of Strained Saturable Bragg Reflector by Chirped Control Pump-Probe Measurement Technique

Wu, Jhong-Rong 29 July 2008 (has links)
In this thesis, a chirp-controlled pump-probe system has been developed to investigate the role of chirp in mode-locking mechanism. By modulating pump power and focusing condition, power, chirp, and wavelength dependent transient reflectivity ( £GR /R), pulse duration, and amplitude ratio in pump-probe measurement for the multiply-strained-quantum-well saturable Bragg reflector (SSBR) are presented. According this study, one can find a more efficient and stable mode-locking mechanism through proper chirp arrangement inside cavity. Compared to the case of transform-limited pump condition, shorter fast-carrier-lifetime and smaller amplitude ratio of slow and fast relaxation contribution are observed in negative chirp excitation condition. Meanwhile, we can see that there is a shorter fast-carrier-lifetime and a smaller amplitude ratio in case of excitation pulse with -25000 ( fs^2 ) chirp or increasing fluence ¡]2 £gm/cm^2->12 £gm/cm^2 ¡^. The results show that the pulse compression strength is stronger in -25000 ( fs^2 ) chirp and full with the tendency demonstrated by pulse shaping factor. All of these experimental results show that -25000 ( fs^2 ) chirp is the best chirped control condition to make mode-locking more efficient and stable. In addition, with the increasing fluence ¡]2 ->12 £gm/cm^2 ¡^, three times of saturable fluence, a more stable and efficient mode-locking condition is expectable.
18

Pump test analogy / Analogt pumptest

Svanberg, Carl January 2015 (has links)
Mycronic is a company that manufactures a solder paste printer used to manufacturecircuit boards. Inside the printer solder paste is fed with the help of a screw pump.The solder paste, consisting of relatively soft metals has a tendency to stick to thescrew surface and form particles. These are then detached and passed on in thesystem and can clog the nozzle of the printer. This project investigated the possibilityof creating a model test where different parameters can be varied to evaluate itsinfluence on the amount of solder paste sticking to the surface of the screw. Testingthese parameters directly in the solder paste printer would be time consuming andexpensive.A pin-on-disk set up with some modified parts was used to emulate the solder pastemotion in the screw pump. The results were then analyzed in light optical microscope(LOM) and scanning electron microscope (SEM) equipped with energy dispersivex-ray spectroscopy (EDS).The parameters that were varied were pressure, temperature, rotation speed,substrate, content of the paste and the shape of the profile, which is supposed toemulate the ridge of the screw. It was shown that the profile shape, the substrate andthe pressure was of great importance in the deformation of the solder balls while therotation speed and the paste content had a small or no effect.The goal of the project is to recreate the agglomerates that have led to malfunctionsin the printing and evaluate which parameters that have the greatest significance.
19

LDA investigation of flow in a stable mixed-flow pump model

Shamsolahi, S. January 1987 (has links)
No description available.
20

New modelling and measurement techniques for liquid-liquid hold-up distribution in agitated tanks

Abid, Kifah Hussain January 1992 (has links)
No description available.

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