22,650 research outputs found
Installation and Instrumentation of Offshore Piles
No full textTypically offshore piles consist of open ended steel pipes which are installed by driving procedures using large steam and/or hydraulic hammers. Often drivability analyses are performed beforehand to establish the optimum combination of pile and hammer for given soil conditions and required pile penetrations. To further monitor and guide actual pile installations, pile and hammer instrumentations are increasingly employed. In this paper drivability analyses and instrumentation methods are briefly explained, as well as the interpretation of instrumentation data. For sake of completeness also two papers are appended in this document. One paper giving more theoretical backgrounds on dynamic pile measurements; a second paper summarising some recent instrumentation projects, successfully completed throughout the offshore world
A novel scanning electrochemical microscopy strategy for the investigation of anomalous hydrogen evolution from AZ63 magnesium alloy
No full textThe evolution of hydrogen gas from corroding magnesium arises not exclusively from the
cathodic half-cell reaction due to the consumption of the electrons released by the dissolving
metal, but anodized magnesium generates significant amounts of H2 gas as well. In addition,
the increase of the anodic overpotential enhances the rate of hydrogen gas generation.
Therefore, spatially-resolved detection of the actual sites for hydrogen evolution related to
anodically-activated sites is attempted using scanning electrochemical microscopy (SECM).
This work describes a new experimental procedure for SECM based on a three-step (off-onoff)
anodization operation sequence that was designed to obtain new insights into the behavior
of magnesium and magnesium alloys when they are subjected to anodic polarization. Results
obtained with scanning electrochemical microscopy (SECM) and scanning vibrating electrode
technique (SVET) experiments presented here demonstrate the catalytic properties of the
magnesium-oxide film for the hydrogen-evolution reactio
A study towards yield optimization for the Expanded Tobacco II process of Philip Morris Holland B.V.
No full textIn the tobacco industry, Philip Morris Holland B.V., part of Philip Morris International, is a cigarette manufacturing company. Within its Primary department tobacco leaves are pretreated in such a way to meet the requirements for cigarette production, which is done in the Secondary department. Tobacco pretreatment processes are: cutting, adding moisture, sauces, semi-finished products and flavors. One of the semi-finished products is expanded tobacco. The aim of a expanded tobacco production process is to stretch the tobacco cells in order to create a permanent volume increase. Tobacco expansion within Philip Morris Holland B.V. is accomplished by means of the Dry Ice Expanded Tobacco technology. In several process steps tobacco cells get impregnated with liquid CO2, which together with the intercellular moisture reacts whereby CO2-hydrate forms. After a impregnation cycle has been completed, the tobacco cells are quickly heated to a temperature of 300ºC. Due to the temperature increase, the CO2-hydrate inside the tobacco cells disintegrates and causes enough gas, and as a result inner pressure, to stretch the cells to the desired volume. The hot expanded tobacco gets cooled down and finally moisture is added to meet the final product requirements. During the several process steps multiple tobacco waste flows, which consist of tobacco fines (dust), are separated from the main tobacco material flow. Since tobacco in general is an expensive material Philip Morris Holland B.V. has the demand for waste reduction…Mechanical, Maritime and Materials EngineeringMarine and Transport TechnologyTransport Engineering and Logistics2014.TEL.783
IMPLEMENTATION BLUETOOTH LOW ENERGY ON THE MEDICAL SUPPORTING DEVICE
No full textNon-compliance from a patient is a serious problem, with a big consequence in case of health and costs. ECCT B.V. tries to develop some supporting devices expected to help patients to report their compliance. One of these supporting devices is a dispenser. These devices record data about time and other clinically relevant information. The electronic circuit also contains RFID technology, it is possible for Near Field Communication (NFC) enabled mobile telephone or a NFC reader to take the stored data.
If we compare Bluetooth with NFC, Bluetooth has an advantage in range, Bluetooth has wider range than NFC. When the dispenser starts using BLE, there is no need for us to make the dispenser close to BLE enabled mobile phone or reader, we can separate it in some distance.
The antenna design was done by using CST Microwave Studio 2009, provided by Fontys Hogescholen. In this project, author uses printed Inverted F Antenna as the antenna. Inverted F Antenna has some advantages and also fulfills the requirements for transmitting and receiving data. From the simulation we can find out there is 7 parameters affected on the antenna performance. Length is one of the parameters affected to the antenna resonant frequency.
From the measurement result, Bluetooth Low Energy for “Firefly” can reach 10 meters range and can stand for 3 years using coin cell battery. In the future, the “Firefly” should be developed in thinner PCB, 0.5mm PCB thickness, because dispenser requires 0.5 mm PCB thickness for the perfect final product.
Keywords: Near Field Communication, Bluetooth Low Energy, and Antenn
Investigation of anomalous hydrogen evolution from anodized magnesium using a polarization routine for scanning electrochemical microscopy
No full textWith the goal to facilitate a new experimental procedure for the monitoring of anomalous
hydrogen evolution from anodically-polarized magnesium-based materials, this paper presents
the application of the three-step (off-on-off) anodization operation sequence for amperometric
scanning electrochemical microscopy (SECM) recently by our group to the characterization of
99.9% magnesium in aqueous saline solution. The SECM measurements done above
prepolarized and nonpolarized magnesium provided new information on the hydrogen
evolution reaction (HER) on this metal, whereas other experiments are presented that enable
to monitor the effect of the oxy-hydroxide layer formed on the metal under anodic
polarization. In addition, direct comparison of the data obtained for 99.9% magnesium with
those previously obtained for AZ63 magnesium alloy contributed to separate the effect of
noble impurities from the catalytic effect of the oxy-hydroxide layer formed on magnesium
for the hydrogen-evolution reactio
Redesign of the control model at SEW-EURODRIVE B.V.
No full textSEW-EURODRIVE B.V. (SEW NL) is a manufacturer of drive products located in Rotterdam in The Netherlands and is a whole subsidiary of the German company SEW-EURODRIVE. SEW NL assembles drives and controllers. Each drive and controller is highly customizable according to the customers wishes and is assembled to order. Lead times are generally short (three workdays). Parts required for assembly of drive products can roughly be divided into two categories: eKanban parts and MRP parts. eKanban parts are small and cheap parts that are put into bins in bulk that are located at places where they are required. Whenever a bin is empty it will be scanned and new parts are ordered. MRP parts are large, more expensive and located in the internal warehouse. These parts are picked before the production order starts. Lead times of SEW NL are shorter than lead times of the supplier of SEW NL (SEW Germany), usually three workdays compared to two to four weeks of SEW Germany. Also, drives and controllers are assembled to order. Because of this, stock is required to meet the lead time requirements. In order to ensure parts never run out of stock, orders are only scheduled when all the required parts are available on the date for which the order is scheduled...Mechanical, Maritime and Materials EngineeringMarine and Transport TechnologyTransport Engineering and Logistics2014-TEL.784
Projective versions of the properties in the Scheepers Diagram
No full textLet P be a topological property. A.V. Arhangel'skii calls X projectively P if every second countable continuous image of X is P. Lj.D.R. Kočinac characterized the classical covering properties of Menger, Rothberger, Hurewicz and Gerlits-Nagy in term of continuous images in Rω. In this paper we study the functional characterizations of all projective versions of the selection properties in the Scheepers Diagram. © 2020 Elsevier B.V
The Erdős–Nagy theorem and its ramifications
No full textAbstractGiven a simple polygon in the plane, a flip is defined as follows: consider the convex hull of the polygon. If there are no pockets do not perform a flip. If there are pockets then reflect one pocket across its line of support of the polygon to obtain a new simple polygon. In 1934 Paul Erdős introduced the problem of repeatedly flipping all the pockets of a simple polygon simultaneously and he conjectured that the polygon would become convex after a finite number of flips. In 1939 Béla Nagy proved that if at each step only one pocket is flipped the polygon will become convex after a finite number of flips. The history of this problem is reviewed, and a simple elementary proof is given of a stronger version of the theorem. Variants, generalizations, and applications of the theorem of interest in computational knot theory, polymer physics and molecular biology are discussed. Several results in the literature are improved with the application of the theorem. For example, Grünbaum and Zaks recently showed that even non-simple (self-crossing) polygons may be convexified in a finite number of suitable flips. Their flips each take Θ(n2) time to determine. A simpler proof of this result is given that yields an algorithm that takes O(n) time to determine each flip. In the context of knot theory Millet proposed an algorithm for convexifying equilateral polygons in 3-dimensions with a generalization of a flip called a pivot. Here Millet's algorithm is generalized so that it works also in dimensions higher than three and for polygons containing edges with arbitrary lengths. A list of open problems is included
A study on the effect of the polymeric additive HPMC on morphology and polymorphism of ortho-aminobenzoic acid crystals
No full textIn the present study, the effect of Hydroxy Propyl Methyl Cellulose (HPMC) on the crystallization of ortho-aminobenzoic acid (OABA) was investigated by seeded and unseeded cooling crystallization experiments. The influence of HPMC on the induction time, crystal shape of Forms I and II of OABA and the polymorphic transformation time was studied. Furthermore, the capability of HPMC to inhibit growth of Form I was evaluated quantitatively and modeled using population balance equations (PBE) solved with the method of moments. The additive was found to strongly inhibit nucleation and growth of Form I as well as to increase the time for the polymorphic transformation from Form II to I. Solvent was also found to influence the shape of Form I crystals at equal concentrations of HPMC. In situ process analytical technology (PAT) tools, including Raman spectroscopy, focused beam reflectance measurement (FBRM) and attenuated total reflectance (ATR) UV-vis spectroscopy were used in combination with off-line techniques, such as optical microscopy, scanning electron microscopy (SEM), Raman spectroscopy, Malvern Mastersizer and differential scanning calorimetry (DSC) to study the crystals produced. The results illustrate how shape, size and stability of the two polymorphs of OABA can be controlled and tailored using a polymeric additive
Computational forging in the Eulerian formulation at MacNeal-Schwendler (E.D.C.) B.V.
No full textThis report is based on eight half-day consultancy visits of the author to MacNeal-Schwendler (E.D.C.) B.V. (MSC-EDC), in the two-month period February-March 1996. The report summarizes the main comments made on the development of computational methods for forging processes at MSC-EDC and gives suggestions for possible future work
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