Using the modern CNC controllers capabilities for estimating the machining forces during the milling process

Directory of Open Access Journals (Sweden)

Breaz Radu-Eugen

2017-01-01

Full Text Available Machining forces can nowadays be measured by using 3D dynamometers, which are usually very expensive devices and hardly available for most of the CNC machine-tools users. On the other hand, modern CNC controllers have nowadays the ability to display and save many outputs within the machining process, such as the currents or even the torques at the shaft's level for the feed motors on each axis. These outputs can be used for estimating the machining forces, but it is to be noticed that the above-mentioned currents and torques are proportional with the overall resistant forces, which includes not only technological forces, but also friction, inertial and pre-tensioning forces. This paper presents an approach for estimating the machining forces during a milling process, by using the outputs stored in the CNC controller and separating the effects of technological forces from the other forces involved in the process. The separation was made by running two sets of experiments, one set for dry-run regime and the other one for machining regime.

CNC-milled titanium frameworks supported by implants in the edentulous jaw: a 10-year comparative clinical study.

Science.gov (United States)

Örtorp, Anders; Jemt, Torsten

2012-03-01

No long-term clinical studies covering more than 5 years are available on Computer Numeric Controlled (CNC) milled titanium frameworks. To evaluate and compare the clinical and radiographic performance of implant-supported prostheses provided with CNC titanium frameworks in the edentulous jaw with prostheses with cast gold-alloy frameworks during the first 10 years of function. Altogether, 126 edentulous patients were by random provided with 67 prostheses with titanium frameworks (test) in 23 maxillas and 44 mandibles, and with 62 prostheses with gold-alloy castings (control) in 31 maxillas and 31 mandibles. Clinical and radiographic 10-year data were collected for the groups and statistically compared on patient level. The 10-year prosthesis and implant cumulative survival rate was 95.6% compared with 98.3%, and 95.0% compared with 97.9% for test and control groups, respectively (p > .05). No implants were lost after 5 years of follow-up. Smokers lost more implants than nonsmokers after 5 years of follow-up (p .05), respectively. One prosthesis was lost in each group due to loss of implants, and one prosthesis failed due to framework fracture in the test group. Two metal fractures were registered in each group. More appointments of maintenance were needed for the prostheses in the maxilla compared with those in the mandible (p CNC-milled titanium frameworks are a viable alternative to gold-alloy castings for restoring patients with implant-supported prostheses in the edentulous jaw. © 2009 Wiley Periodicals, Inc.

Continuous tone printing in silicone from CNC milled matrices

Science.gov (United States)

Hoskins, S.; McCallion, P.

2014-02-01

Current research at the Centre for Fine Print Research (CFPR) at the University of the West of England, Bristol, is exploring the potential of creating coloured pictorial imagery from a continuous tone relief surface. To create the printing matrices the research team have been using CNC milled images where the height of the relief image is dictated by creating a tone curve and then milling this curve into a series of relief blocks from which the image is cast in a silicone ink. A translucent image is cast from each of the colour matrices and each colour is assembled - one on top of another - resulting is a colour continuous tone print, where colour tone is created by physical depth of colour. This process is a contemporary method of continuous tone colour printing based upon the Nineteenth Century black and white printing process of Woodburytype as developed by Walter Bentley Woodbury in 1865. Woodburytype is the only true continuous tone printing process invented, and although its delicate and subtle surfaces surpassed all other printing methods at the time. The process died out in the late nineteenth century as more expedient and cost effective methods of printing prevailed. New research at CFPR builds upon previous research that combines 19th Century Photomechanical techniques with digital technology to reappraise the potential of these processes.

Understanding and Writing G & M Code for CNC Machines

Science.gov (United States)

Loveland, Thomas

2012-01-01

In modern CAD and CAM manufacturing companies, engineers design parts for machines and consumable goods. Many of these parts are cut on CNC machines. Whether using a CNC lathe, milling machine, or router, the ideas and designs of engineers must be translated into a machine-readable form called G & M Code that can be used to cut parts to precise…

ANN Based Tool Condition Monitoring System for CNC Milling Machines

Directory of Open Access Journals (Sweden)

Mota-Valtierra G.C.

2011-10-01

Full Text Available Most of the companies have as objective to manufacture high-quality products, then by optimizing costs, reducing and controlling the variations in its production processes it is possible. Within manufacturing industries a very important issue is the tool condition monitoring, since the tool state will determine the quality of products. Besides, a good monitoring system will protect the machinery from severe damages. For determining the state of the cutting tools in a milling machine, there is a great variety of models in the industrial market, however these systems are not available to all companies because of their high costs and the requirements of modifying the machining tool in order to attach the system sensors. This paper presents an intelligent classification system which determines the status of cutt ers in a Computer Numerical Control (CNC milling machine. This tool state is mainly detected through the analysis of the cutting forces drawn from the spindle motors currents. This monitoring system does not need sensors so it is no necessary to modify the machine. The correct classification is made by advanced digital signal processing techniques. Just after acquiring a signal, a FIR digital filter is applied to the data to eliminate the undesired noisy components and to extract the embedded force components. A Wavelet Transformation is applied to the filtered signal in order to compress the data amount and to optimize the classifier structure. Then a multilayer perceptron- type neural network is responsible for carrying out the classification of the signal. Achieving a reliability of 95%, the system is capable of detecting breakage and a worn cutter.

Flank wears Simulation by using back propagation neural network when cutting hardened H-13 steel in CNC End Milling

Science.gov (United States)

Hazza, Muataz Hazza F. Al; Adesta, Erry Y. T.; Riza, Muhammad

2013-12-01

High speed milling has many advantages such as higher removal rate and high productivity. However, higher cutting speed increase the flank wear rate and thus reducing the cutting tool life. Therefore estimating and predicting the flank wear length in early stages reduces the risk of unaccepted tooling cost. This research presents a neural network model for predicting and simulating the flank wear in the CNC end milling process. A set of sparse experimental data for finish end milling on AISI H13 at hardness of 48 HRC have been conducted to measure the flank wear length. Then the measured data have been used to train the developed neural network model. Artificial neural network (ANN) was applied to predict the flank wear length. The neural network contains twenty hidden layer with feed forward back propagation hierarchical. The neural network has been designed with MATLAB Neural Network Toolbox. The results show a high correlation between the predicted and the observed flank wear which indicates the validity of the models.

Flank wears Simulation by using back propagation neural network when cutting hardened H-13 steel in CNC End Milling

International Nuclear Information System (INIS)

Al Hazza, Muataz Hazza F; Adesta, Erry Y T; Riza, Muhammad

2013-01-01

High speed milling has many advantages such as higher removal rate and high productivity. However, higher cutting speed increase the flank wear rate and thus reducing the cutting tool life. Therefore estimating and predicting the flank wear length in early stages reduces the risk of unaccepted tooling cost. This research presents a neural network model for predicting and simulating the flank wear in the CNC end milling process. A set of sparse experimental data for finish end milling on AISI H13 at hardness of 48 HRC have been conducted to measure the flank wear length. Then the measured data have been used to train the developed neural network model. Artificial neural network (ANN) was applied to predict the flank wear length. The neural network contains twenty hidden layer with feed forward back propagation hierarchical. The neural network has been designed with MATLAB Neural Network Toolbox. The results show a high correlation between the predicted and the observed flank wear which indicates the validity of the models

Case study of virtual reality in CNC machine tool exhibition

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Kao Yung-Chou

2017-01-01

Full Text Available Exhibition and demonstration are generally used in the promotion and sale-assistance of manufactured products. However, the transportation cost of the real goods from the vender factory to the exposition venue is generally expensive for huge and heavy commodity. With the advancement of computing, graphics, mobile apps, and mobile hardware the 3D visibility technology is getting more and more popular to be adopted in visual-assisted communication such as amusement games. Virtual reality (VR technology has therefore being paid great attention in emulating expensive small and/or huge and heavy equipment. Virtual reality can be characterized as 3D extension with Immersion, Interaction and Imagination. This paper was then be focused on the study of virtual reality in the assistance of CNC machine tool demonstration and exhibition. A commercial CNC machine tool was used in this study to illustrate the effectiveness and usability of using virtual reality for an exhibition. The adopted CNC machine tool is a large and heavy mill-turn machine with the width up to eleven meters and weighted about 35 tons. A head-mounted display (HMD was attached to the developed VR CNC machine tool for the immersion viewing. A user can see around the 3D scene of the large mill-turn machine and the operation of the virtual CNC machine can be actuated by bare hand. Coolant was added to demonstrate more realistic operation while collision detection function was also added to remind the operator. The developed VR demonstration system has been presented in the 2017 Taipei International Machine Tool Show (TIMTOS 2017. This case study has shown that young engineers and/or students are very impressed by the VR-based demonstration while elder persons could not adapt themselves easily to the VR-based scene because of eyesight issues. However, virtual reality has successfully being adopted and integrated with the CNC machine tool in an international show. Another machine tool on

Design and implementation of five-axis transformation function in CNC system

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Wang Feng

2014-04-01

Full Text Available To implement five-axis functions in CNC system, based on domestic system Lan Tian series, an improved design method for the system software structure is proposed in this paper. The numerical control kernel of CNC system is divided into the task layer and the motion layer. A five-axis transformation unit is integrated into the motion layer. After classifying five-axis machines into different types and analyzing their geometry information, the five-axis kinematic library is designed according to the abstract factory pattern. Furthermore, by taking CA spindle-tilting machine as an example, the forward and the inverse kinematic transformations are deduced. Based on the new software architecture and the five-axis kinematic library, algorithms of RTCP (rotation tool center point control and 3D radius compensation for end-milling are designed and realized. The milling results show that, with five-axis functions based on such software structure, the instructions with respect to the cutter’s position and orientation can be directly carried out in the CNC system.

Cuttable Ruled Surface Strips for Milling

DEFF Research Database (Denmark)

Steenstrup, Kasper Hornbak; Nørbjerg, Toke Bjerge; Søndergaard, Asbjørn

2016-01-01

This paper proposes a novel pre-processing method for industrial robotic CNC-milling. The method targets a hybrid machining process, in which the main bulk of material is removed through robotic hot or abrasive wire cutting, after which regular CNC-machining is employed for removal of the remaining...

PENGEMBANGAN MESIN CNC VIRTUAL SEBAGAI MEDIA INTERAKTIF DALAM PEMBELAJARAN PEMROGRAMAN CNC

OpenAIRE

Bambang Setyo Hari Purwoko

2013-01-01

Penelitian ini bertujuan: (1) menghasilkan prototype tampilan lingkungan fisik sebuah mesin bubut CNC (Virtual Reality CNC) pada layar komputer yang dapat menerima masukan dan dioperasikan sebagaimana suatu mesin CNC dan (2) menguji keefektifan prototype mesin CNC Virtual tersebut sebagai media interaktif pembelajaran pemrograman CNC. Penelitian ini merupakan penelitian pengembangan. Obyek penelitian adalah rekayasa pemrograman dengan bahasa Visual Basic 6 guna menghasilkan mesin CNC Virtual....

Shear bond strength of veneering porcelain to zirconia: Effect of surface treatment by CNC-milling and composite layer deposition on zirconia.

Science.gov (United States)

Santos, R L P; Silva, F S; Nascimento, R M; Souza, J C M; Motta, F V; Carvalho, O; Henriques, B

2016-07-01

The purpose of this study was to evaluate the shear bond strength of veneering feldspathic porcelain to zirconia substrates modified by CNC-milling process or by coating zirconia with a composite interlayer. Four types of zirconia-porcelain interface configurations were tested: RZ - porcelain bonded to rough zirconia substrate (n=16); PZ - porcelain bonded to zirconia substrate with surface holes (n=16); RZI - application of a composite interlayer between the veneering porcelain and the rough zirconia substrate (n=16); PZI - application of a composite interlayer between the porcelain and the zirconia substrate treated by CNC-milling (n=16). The composite interlayer was composed of zirconia particles reinforced porcelain (30%, vol%). The mechanical properties of the ceramic composite have been determined. The shear bond strength test was performed at 0.5mm/min using a universal testing machine. The interfaces of fractured and untested specimens were examined by FEG-SEM/EDS. Data was analyzed with Shapiro-Wilk test to test the assumption of normality. The one-way ANOVA followed by Tukey HSD multiple comparison test was used to compare shear bond strength results (α=0.05). The shear bond strength of PZ (100±15MPa) and RZI (96±11MPa) specimens were higher than that recorded for RZ (control group) specimens (89±15MPa), although not significantly (p>0.05). The highest shear bond strength values were recorded for PZI specimens (138±19MPa), yielding a significant improvement of 55% relative to RZ specimens (p<0.05). This study shows that it is possible to highly enhance the zirconia-porcelain bond strength - even by ~55% - by combining surface holes in zirconia frameworks and the application of a proper ceramic composite interlayer. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Multiple Model Prediction Algorithm for CNC Machine Wear PHM

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Huimin Chen

2011-01-01

Full Text Available The 2010 PHM data challenge focuses on the remaining useful life (RUL estimation for cutters of a high speed CNC milling machine using measurements from dynamometer, accelerometer, and acoustic emission sensors. We present a multiple model approach for wear depth estimation of milling machine cutters using the provided data. The feature selection, initial wear estimation and multiple model fusion components of the proposed algorithm are explained in details and compared with several alternative methods using the training data. The final submission ranked #2 among professional and student participants and the method is applicable to other data driven PHM problems.

Development of Client-Server Application by Using UDP Socket Programming for Remotely Monitoring CNC Machine Environment in Fixture Process

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Darmawan Darmawan

2016-08-01

Full Text Available The use of computer technology in manufacturing industries can improve manufacturing flexibility significantly, especially in manufacturing processes; many software applications have been utilized to improve machining performance. However, none of them has discussed the abilities to perform direct machining. In this paper, an integrated system for remote operation and monitoring of Computer Numerical Control (CNC machines is put into consideration. The integrated system includes computerization, network technology, and improved holding mechanism. The work proposed by this research is mainly on the software development for such integrated system. It uses Java three-dimensional (3D programming and Virtual Reality Modeling Language (VRML at the client side for visualization of machining environment. This research is aimed at developing a control system to remotely operate and monitor a self-reconfiguration fixture mechanism of a CNC milling machine through internet connection and integration of Personal Computer (PC-based CNC controller, a server side, a client side and CNC milling. The performance of the developed system was evaluated by testing with one type of common protocols particularly User Datagram Protocol (UDP.  Using UDP, the developed system requires 3.9 seconds to complete the close clamping, less than 1 second to release the clamping and it can deliver 463 KiloByte.

Carney complex (CNC).

Science.gov (United States)

Bertherat, Jérôme

2006-06-06

The Carney complex (CNC) is a dominantly inherited syndrome characterized by spotty skin pigmentation, endocrine overactivity and myxomas. Skin pigmentation anomalies include lentigines and blue naevi. The most common endocrine gland manifestations are acromegaly, thyroid and testicular tumors, and adrenocorticotropic hormone (ACTH)-independent Cushing's syndrome due to primary pigmented nodular adrenocortical disease (PPNAD). PPNAD, a rare cause of Cushing's syndrome, is due to primary bilateral adrenal defect that can be also observed in some patients without other CNC manifestations or familial history of the disease. Myxomas can be observed in the heart, skin and breast. Cardiac myxomas can develop in any cardiac chamber and may be multiple. One of the putative CNC genes located on 17q22-24, (PRKAR1A), has been identified to encode the regulatory subunit (R1A) of protein kinase A. Heterozygous inactivating mutations of PRKAR1A were reported initially in 45 to 65% of CNC index cases, and may be present in about 80% of the CNC families presenting mainly with Cushing's syndrome. PRKAR1A is a key component of the cAMP signaling pathway that has been implicated in endocrine tumorigenesis and could, at least partly, function as a tumor suppressor gene. Genetic analysis should be proposed to all CNC index cases. Patients with CNC or with a genetic predisposition to CNC should have regular screening for manifestations of the disease. Clinical work-up for all the manifestations of CNC should be performed at least once a year in all patients and should start in infancy. Cardiac myxomas require surgical removal. Treatment of the other manifestations of CNC should be discussed and may include follow-up, surgery, or medical treatment depending on the location of the tumor, its size, the existence of clinical signs of tumor mass or hormonal excess, and the suspicion of malignancy. Bilateral adrenalectomy is the most common treatment for Cushing's syndrome due to PPNAD.

Carney complex (CNC

Directory of Open Access Journals (Sweden)

Bertherat Jérôme

2006-06-01

Full Text Available Abstract The Carney complex (CNC is a dominantly inherited syndrome characterized by spotty skin pigmentation, endocrine overactivity and myxomas. Skin pigmentation anomalies include lentigines and blue naevi. The most common endocrine gland manifestations are acromegaly, thyroid and testicular tumors, and adrenocorticotropic hormone (ACTH-independent Cushing's syndrome due to primary pigmented nodular adrenocortical disease (PPNAD. PPNAD, a rare cause of Cushing's syndrome, is due to primary bilateral adrenal defect that can be also observed in some patients without other CNC manifestations or familial history of the disease. Myxomas can be observed in the heart, skin and breast. Cardiac myxomas can develop in any cardiac chamber and may be multiple. One of the putative CNC genes located on 17q22-24, (PRKAR1A, has been identified to encode the regulatory subunit (R1A of protein kinase A. Heterozygous inactivating mutations of PRKAR1A were reported initially in 45 to 65 % of CNC index cases, and may be present in about 80 % of the CNC families presenting mainly with Cushing's syndrome. PRKAR1A is a key component of the cAMP signaling pathway that has been implicated in endocrine tumorigenesis and could, at least partly, function as a tumor suppressor gene. Genetic analysis should be proposed to all CNC index cases. Patients with CNC or with a genetic predisposition to CNC should have regular screening for manifestations of the disease. Clinical work-up for all the manifestations of CNC should be performed at least once a year in all patients and should start in infancy. Cardiac myxomas require surgical removal. Treatment of the other manifestations of CNC should be discussed and may include follow-up, surgery, or medical treatment depending on the location of the tumor, its size, the existence of clinical signs of tumor mass or hormonal excess, and the suspicion of malignancy. Bilateral adrenalectomy is the most common treatment for Cushing

A comparison between customized clear and removable orthodontic appliances manufactured using RP and CNC techniques.

Science.gov (United States)

Martorelli, Massimo; Gerbino, Salvatore; Giudice, Michele; Ausiello, Pietro

2013-02-01

Aim of the research is to compare the orthodontic appliances fabricated by using rapid prototyping (RP) systems, in particular 3D printers, with those manufactured by using computer numerical control (CNC) milling machines. 3D printing is today a well-accepted technology to fabricate orthodontic aligners by using the thermoforming process, instead the potential of CNC systems in dentistry have not yet been sufficiently explored. One patient, with mal-positioned maxillary central and lateral incisors, was initially selected. In the computer aided virtual planning was defined that, for the treatment, the patient needed to wear a series of 7 removable orthodontic appliances (ROA) over a duration of 21 weeks, with one appliance for every 3 weeks. A non-contact reverse engineering (RE) structured-light 3D scanner was used to create the 3D STL model of the impression of the patient's mouth. Numerical FEM simulations were performed varying the position of applied forces (discrete and continuous forces) on the same model, simulating, in this way, 3 models with slice thickness of 0.2 mm, 0.1 mm (RP staircase effect) and without slicing (ideal case). To define the areas of application of forces, two configuration "i" and "i-1" of the treatment were overlapped. 6 patients to which for three steps (3rd, 4th and 5th step) were made to wear aligners fabricated starting from physical models by 3D printing (3DP-ROA) and afterwards, for the next steps (6th, 7th and 8th step), aligners fabricated starting from physical models by CNC milling machine (CNC-ROA), were selected. For the 6 patients wearing the CNC-ROA, it was observed a best fitting of the aligner to the teeth and a more rapid teeth movement than the 3DP-ROA (2 weeks compared to 3 weeks for every appliance). FEM simulations showed a more uniform stress distribution for CNC-ROA than 3DP-ROA. In this research, 6 different case studies and CAD-FEM simulations showed that, to fabricate an efficient clear and removable

Open architecture CNC system

Energy Technology Data Exchange (ETDEWEB)

Tal, J. [Galil Motion Control Inc., Sunnyvale, CA (United States); Lopez, A.; Edwards, J.M. [Los Alamos National Lab., NM (United States)

1995-04-01

In this paper, an alternative solution to the traditional CNC machine tool controller has been introduced. Software and hardware modules have been described and their incorporation in a CNC control system has been outlined. This type of CNC machine tool controller demonstrates that technology is accessible and can be readily implemented into an open architecture machine tool controller. Benefit to the user is greater controller flexibility, while being economically achievable. PC based, motion as well as non-motion features will provide flexibility through a Windows environment. Up-grading this type of controller system through software revisions will keep the machine tool in a competitive state with minimal effort. Software and hardware modules are mass produced permitting competitive procurement and incorporation. Open architecture CNC systems provide diagnostics thus enhancing maintainability, and machine tool up-time. A major concern of traditional CNC systems has been operator training time. Training time can be greatly minimized by making use of Windows environment features.

Failure probabilistic model of CNC lathes

International Nuclear Information System (INIS)

Wang Yiqiang; Jia Yazhou; Yu Junyi; Zheng Yuhua; Yi Shangfeng

1999-01-01

A field failure analysis of computerized numerical control (CNC) lathes is described. Field failure data was collected over a period of two years on approximately 80 CNC lathes. A coding system to code failure data was devised and a failure analysis data bank of CNC lathes was established. The failure position and subsystem, failure mode and cause were analyzed to indicate the weak subsystem of a CNC lathe. Also, failure probabilistic model of CNC lathes was analyzed by fuzzy multicriteria comprehensive evaluation

CNC Programming I.

Science.gov (United States)

Casey, Joe

This document contains five units for a course in computer numerical control (CNC) for computer-aided manufacturing. It is intended to familiarize students with the principles and techniques necessary to create proper CNC programs manually. Each unit consists of an introduction, instructional objectives, learning materials, learning activities,…

Towards efficient 5-axis flank CNC machining of free-form surfaces via fitting envelopes of surfaces of revolution

OpenAIRE

Bo P.; Bartoň M.; Plakhotnik D.; Pottmann H.

2016-01-01

We introduce a new method that approximates free-form surfaces by envelopes of one-parameter motions of surfaces of revolution. In the context of 5-axis computer numerically controlled (CNC) machining, we propose a flank machining methodology which is a preferable scallop-free scenario when the milling tool and the machined free-form surface meet tangentially along a smooth curve. We seek both an optimal shape of the milling tool as well as its optimal path in 3D space and propose an optimiza...

Effect of cellulose nanocrystals (CNC) on rheological and mechanical properties and crystallization behavior of PLA/CNC nanocomposites.

Science.gov (United States)

Kamal, Musa R; Khoshkava, Vahid

2015-06-05

In earlier work, we reported that spray freeze drying of cellulose nanocrystals (CNC) yields porous agglomerate structures. On the other hand, the conventional spray dried CNC (CNCSD) and the freeze dried CNC (CNCFD) produce compact solid structures with very low porosity. As it is rather difficult to obtain direct microscopic evidence of the quality of dispersion of CNC in polymer nanocomposites, it was shown that supporting evidence of the quality and influence of dispersion in a polypropylene (PP)/CNC nanocomposite could be obtained by studying the rheological behavior, mechanical properties and crystallization characteristics of PP/CNC nanocomposites. In an effort to produce a sustainable, fully biosourced, biodegradable nanocomposite, this manuscript presents the results of a study of the rheological, mechanical and crystallization behavior of PLA/CNCSFD nanocomposites obtained by melt processing. The results are analyzed to determine CNC network formation, rheological percolation threshold concentrations, mechanical properties in the rubbery and glassy states, and the effect of CNCSFD on crystalline nucleation and crystallization rates of PLA. These results suggest that the porosity and network structure of CNCSFD agglomerates contribute significantly to good dispersion of CNC in the PLA matrix. Copyright © 2015 Elsevier Ltd. All rights reserved.

Theory and design of CNC systems

CERN Document Server

Suh, Suk-Hwan; Chung, Dae-Hyuk; Stroud, Ian

2008-01-01

Computer Numerical Control (CNC) controllers are high value-added products counting for over 30% of the price of machine tools. The development of CNC technology depends on the integration of technologies from many different industries, and requires strategic long-term support. a oeTheory and Design of CNC Systemsa covers the elements of control, the design of control systems, and modern open-architecture control systems. Topics covered include Numerical Control Kernel (NCK) design of CNC, Programmable Logic Control (PLC), and the Man-Machine Interface (MMI), as well as the major modules for t

Review on CNC-Rapid Prototyping

International Nuclear Information System (INIS)

M Nafis O Z; Nafrizuan M Y; Munira M A; Kartina J

2012-01-01

This article reviewed developments of Computerized Numerical Control (CNC) technology in rapid prototyping process. Rapid prototyping (RP) can be classified into three major groups; subtractive, additive and virtual. CNC rapid prototyping is grouped under the subtractive category which involves material removal from the workpiece that is larger than the final part. Richard Wysk established the use of CNC machines for rapid prototyping using sets of 2½-D tool paths from various orientations about a rotary axis to machine parts without refixturing. Since then, there are few developments on this process mainly aimed to optimized the operation and increase the process capabilities to stand equal with common additive type of RP. These developments include the integration between machining and deposition process (hybrid RP), adoption of RP to the conventional machine and optimization of the CNC rapid prototyping process based on controlled parameters. The article ended by concluding that the CNC rapid prototyping research area has a vast space for improvement as in the conventional machining processes. Further developments and findings will enhance the usage of this method and minimize the limitation of current approach in building a prototype.

An Experiment Study on Surface Roughness in High Speed Milling NAK80 Die Steel

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Su Fa

2016-01-01

Full Text Available The paper introduces that the high speed milling experiments on NAK80 die steel was carried out on the DMU 60 mono BLOCK five axis linkage high speed CNC machining center tool by the TiAlN coated tools, in order to research the effect of milling parameters on surface roughness Ra. The results showed that the Ra value increased with the decrease of milling speed vc, increased with the axial depth of milling ap, and feed per tooth fz and radial depth of milling ae. On the basis of the single factor experiment results, the mathematics model for between surface roughness and milling parameters were established by linear regression analysis.

Milling damage on Carbon Fibre Reinforced Polymer using TiAlN coated End mills

International Nuclear Information System (INIS)

Konneh, Mohamed; Kassim, Abdullah Abdul Rahman; Izman, Sudin

2015-01-01

This paper reports on the damage caused by milling Carbon Fibre Reinforced Composite (CFRP) with 2-flute 4 mm-diameter solid carbide end mills, coated with titanium aluminium nitride. The machining parameters considered in work are, rotation speed, feed rate and depth of cut. Experiments were designed based on Box-Behnken design and the experiments conducted on a Mikrotool DT-110 CNC micro machine. A laser tachometer was used to ascertain a rotational speed for conducting any machining trial. Optical microscopy examination reveals minimum delamination value of 4.05 mm at the spindle speed of 25,000 rpm, depth of cut of 50μm and feed rate of 3 mm/min and the maximum delamination value of 5.04 mm at the spindle speed of 35000 rpm, depth of cut of 150μm and feed rate of 9 mm/min A mathematical model relating the milling parameters and delamination has been established. (paper)

Milling damage on Carbon Fibre Reinforced Polymer using TiAlN coated End mills

Science.gov (United States)

Konneh, Mohamed; Izman, Sudin; Rahman Kassim, Abdullah Abdul

2015-07-01

This paper reports on the damage caused by milling Carbon Fibre Reinforced Composite (CFRP) with 2-flute 4 mm-diameter solid carbide end mills, coated with titanium aluminium nitride. The machining parameters considered in work are, rotation speed, feed rate and depth of cut. Experiments were designed based on Box-Behnken design and the experiments conducted on a Mikrotool DT-110 CNC micro machine. A laser tachometer was used to ascertain a rotational speed for conducting any machining trial. Optical microscopy examination reveals minimum delamination value of 4.05 mm at the spindle speed of 25,000 rpm, depth of cut of 50μm and feed rate of 3 mm/min and the maximum delamination value of 5.04 mm at the spindle speed of 35000 rpm, depth of cut of 150μm and feed rate of 9 mm/min A mathematical model relating the milling parameters and delamination has been established.

Tool Wear Analysis on Five-Axis Flank Milling for Curved Shape Part – Full Flute and Ground Shank End Mill

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Syahrul Azwan Sundi

2017-01-01

Full Text Available This paper is a study on full flute (extra-long tool and ground shank end mill wear analysis by utilizing five-axis CNC to implement flank milling strategy on curved shape part. Five-axis machining eases the user to implement variations of strategy such as flank milling. Flank milling is different from point milling. Point milling cuts materials by using the tip of the tool whereas the flank milling uses the cutting tool body to cut material. The type of cutting tool used was end mill 10 mm diameter with High Speed Steel (HSS material. One factor at a time was utilized to analyze the overall data. Feed rate and spindle speed were the two main factors that been set up equally for both full flute and ground shank end mill. At the end of this research, the qualitative analysis based on tool wear between full flute and ground shank end mill is observed. Generally, both types of cutting tools showed almost the same failure indication such as broken edge or chipped off edge, formation of pinned hole on the surface and serration formation or built-up edge (BUE on the primary flute. However, the results obtained from the enlarged images which were captured by Optical Microscope indicated that, the ground shank end mill is better than the full flute end mill.

5-axes modular CNC machining center

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Breaz Radu-Eugen

2017-01-01

Full Text Available The paper presents the development of a 5-axes CNC machining center. The main goal of the machine was to provide the students a practical layout for training in advanced CAM techniques. The mechanical structure of the machine was built in a modular way by a specialized company, which also implemented the CNC controller. The authors of this paper developed the geometric and kinematic model of the CNC machining center and the post-processor, in order to use the machine in a CAM environment.

Milling properties of low temperature sintered zirconia blocks for dental use

Energy Technology Data Exchange (ETDEWEB)

Lan, Ting-Hsun; Wang, Chau-Hsiang [Department of Prosthodontics, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan (China); School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 80728, Taiwan (China); Chen, Ker-Kong [Department of Conservation, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan (China); School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 80728, Taiwan (China); Wang, Moo-Chin, E-mail: mcwang@kmu.edu.tw [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 80728, Taiwan (China); Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, 80756, Taiwan (China); Lee, Huey-Er, E-mail: huerle@kmu.edu.tw [Department of Prosthodontics, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan (China); School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 80728, Taiwan (China)

2017-04-01

To investigate the milling properties of different yttria-tetragonal zirconia polycrystalline (Y-TZP) block materials by applying a dental computer numerical control (CNC) milling center. Low temperature sintering zirconia block denoted by KMUZ (experimental) with two commercial zirconia blocks for T block made in Taiwan and a G block made in Germany were compared for the milling properties. Seventy-two specimens were milled using the same CNC milling center, and properties were evaluated by measuring the weight loss (g), milling time (s), margin integrity (%) and broken diameter (μm). The crystalline phases contents were identified by X-ray diffraction and the microstructures of the sintering specimens were observed by scanning electron microscopy and transmission electron microscopy. The mean milling time of G and KMUZ were significantly shorter than T (P < 0.05). The KMUZ samples exhibited the least weight loss among the three kinds of blocks (P < 0.05). The percentages of marginal integrity after milling were high in G and KMUZ but low in T (P < 0.05). The mean broken diameters were from 90 μm to 120 μm. The phase transformation of t-ZrO{sub 2} (KMUZ: 7.4%, G: 5.9%, T: 3.2%) to m-ZrO{sub 2} when facing the milling pressure in ZrO{sub 2} blocks was observed by XRD. The result of TEM microstructure of KMUZ revealed that Y and Si were soluble in grain boundaries. The results show that the milling properties of KMUZ were better than one commercial T and near the G. The hindered grain growth, as a result of the Y{sup 3+} content in the grain boundaries, also plays a role in promoting the abnormal grain growth of 3Y-TZP. - Highlights: • The phase transformation of t-ZrO{sub 2} to m-ZrO{sub 2} affects the milling properties. • The phase content of t-ZrO2 was 100% when sintering at 1350 °C for 2 h. • The Y{sup 3+} content in the grain boundaries that hinders grain growth. • The Y{sup 3+} content in boundaries also promotes the abnormal grain growth of 3Y-TZP.

Curcumin-carboxymethyl chitosan (CNC) conjugate and CNC/LHR mixed polymeric micelles as new approaches to improve the oral absorption of P-gp substrate drugs.

Science.gov (United States)

Ni, Jiang; Tian, Fengchun; Dahmani, Fatima Zohra; Yang, Hui; Yue, Deren; He, Shuwang; Zhou, Jianping; Yao, Jing

2016-11-01

The low oral bioavailability of numerous drugs has been mostly attributed to the significant effect of P-gp-mediated efflux on intestinal drug transport. Herein, we developed mixed polymeric micelles (MPMs) comprised of curcumin-carboxymethyl chitosan (CNC) conjugate, as a potential inhibitor of P-gp-mediated efflux and gastrointestinal absorption enhancer, and low-molecular-weight heparin-all-trans-retinoid acid (LHR) conjugate, as loading material, with the aim to improve the oral absorption of P-gp substrate drugs. CNC conjugate was synthesized by chemical bonding of curcumin (Cur) and carboxymethyl chitosan (CMCS) taking advantage of the inhibition of intestinal P-gp-mediated secretion by Cur and the intestinal absorption enhancement by CMCS. The chemical structure of CNC conjugate was characterized by 1 H NMR with a degree of substitution of Cur of 4.52-10.20%. More importantly, CNC conjugate markedly improved the stability of Cur in physiological pH. Cyclosporine A-loaded CNC/LHR MPMs (CsA-CNC/LHR MPMs) were prepared by dialysis method, with high drug loading 25.45% and nanoscaled particle size (∼200 nm). In situ single-pass perfusion studies in rats showed that both CsA + CNC mixture and CsA-CNC/LHR MPMs achieved significantly higher K a and P eff than CsA suspension in the duodenum and jejunum segments (p CNC mixture and CsA-CNC/LHR MPMs significantly increased the oral bioavailability of CsA as compared to CsA suspension. These results suggest that CNC conjugate might be considered as a promising gastrointestinal absorption enhancer, while CNC/LHR MPMs had the potential to improve the oral absorption of P-gp substrate drugs.

The Tool Life of Ball Nose end Mill Depending on the Different Types of Ramping

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Vopát, Tomáš; Peterka, Jozef; Kováč, Martin

2014-12-01

The article deals with the cutting tool wear measurement process and tool life of ball nose end mill depending on upward ramping and downward ramping. The aim was to determine and compare the wear (tool life) of ball nose end mill for different types of copy milling operations, as well as to specify particular steps of the measurement process. In addition, we examined and observed cutter contact areas of ball nose end mill with machined material. For tool life test, DMG DMU 85 monoBLOCK 5-axis CNC milling machine was used. In the experiment, cutting speed, feed rate, axial depth of cut and radial depth of cut were not changed. The cutting tool wear was measured on Zoller Genius 3s universal measuring machine. The results show different tool life of ball nose end mills depending on the copy milling strategy.

Detecting Milling Deformation in 7075 Aluminum Alloy Aeronautical Monolithic Components Using the Quasi-Symmetric Machining Method

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Qiong Wu

2016-04-01

Full Text Available The deformation of aeronautical monolithic components due to CNC machining is a bottle-neck issue in the aviation industry. The residual stress releases and redistributes in the process of material removal, and the distortion of the monolithic component is generated. The traditional one-side machining method will produce oversize deformation. Based on the three-stage CNC machining method, the quasi-symmetric machining method is developed in this study to reduce deformation by symmetry material removal using the M-symmetry distribution law of residual stress. The mechanism of milling deformation due to residual stress is investigated. A deformation experiment was conducted using traditional one-side machining method and quasi-symmetric machining method to compare with finite element method (FEM. The deformation parameters are validated by comparative results. Most of the errors are within 10%. The reason for these errors is determined to improve the reliability of the method. Moreover, the maximum deformation value of using quasi-symmetric machining method is within 20% of that of using the traditional one-side machining method. This result shows the quasi-symmetric machining method is effective in reducing deformation caused by residual stress. Thus, this research introduces an effective method for reducing the deformation of monolithic thin-walled components in the CNC milling process.

Effect of cellulose nanocrystals (CNC) particle morphology on dispersion and rheological and mechanical properties of polypropylene/CNC nanocomposites.

Science.gov (United States)

Khoshkava, Vahid; Kamal, Musa R

2014-06-11

Polypropylene (PP) nanocomposites containing spray-dried cellulose nanocrystals (CNC), freeze-dried CNC, and spray-freeze-dried CNC (CNCSFD) were prepared via melt mixing in an internal batch mixer. Polarized light, scanning electron, and atomic force microscopy showed significantly better dispersion of CNCSFD in PP/CNC nanocomposites compared with the spray-dried and freeze-dried CNCs. Rheological measurements, including linear and nonlinear viscoelastic tests, were performed on PP/CNC samples. The microscopy results were supported by small-amplitude oscillatory shear tests, which showed substantial rises in the magnitudes of key rheological parameters of PP samples containing CNCSFD. Steady-shear results revealed a strong shear thinning behavior of PP samples containing CNCSFD. Moreover, PP melts containing CNCSFD exhibited a yield stress. The magnitude of the yield stress and the degree of shear thinning behavior increased with CNCSFD concentration. It was found that CNCSFD agglomerates with a weblike structure were more effective in modifying the rheological properties. This effect was attributed to better dispersion of the agglomerates with the weblike structure. Dynamic mechanical analysis showed considerable improvement in the modulus of samples containing CNCSFD agglomerates. The percolation mechanical model with modified volume percolation threshold and filler network strength values and the Halpin-Kardos model were used to fit the experimental results.

Mini lathe machine converted to CNC

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Alexandru Morar

2012-06-01

Full Text Available This paper presents the adaptation of a mechanical mini-lathing machine to a computerized numerical control (CNC lathing machine. This machine is composed of a ASIST mini-lathe and a two-degrees-of-freedom XZ stage designed specifically for this application. The whole system is controlled from a PC using adequate CNC control software.

The Tool Life of Ball Nose end Mill Depending on the Different Types of Ramping

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Vopát Tomáš

2014-12-01

Full Text Available The article deals with the cutting tool wear measurement process and tool life of ball nose end mill depending on upward ramping and downward ramping. The aim was to determine and compare the wear (tool life of ball nose end mill for different types of copy milling operations, as well as to specify particular steps of the measurement process. In addition, we examined and observed cutter contact areas of ball nose end mill with machined material. For tool life test, DMG DMU 85 monoBLOCK 5-axis CNC milling machine was used. In the experiment, cutting speed, feed rate, axial depth of cut and radial depth of cut were not changed. The cutting tool wear was measured on Zoller Genius 3s universal measuring machine. The results show different tool life of ball nose end mills depending on the copy milling strategy.

Singer CNC sewing and embroidery machine

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Lokodi Zsolt

2011-12-01

Full Text Available This paper presents the adaptation of a classic foot pedal operated Singer sewing machine to a computerized numerical control (CNC sewing and embroidery machine. This machine is composed of a Singer sewing machine and a two-degrees-of-freedom XY stage designed specifically for this application. The whole system is controlled from a PC using adequate CNC control software.

Highly Modified Cellulose Nanocrystals and Formation of Epoxy-CNC Nanocomposites.

Science.gov (United States)

Abraham, Eldho; Kam, Doron; Nevo, Yuval; Slattegard, Rikard; Rivkin, Amit; Lapidot, Shaul; Shoseyov, Oded

2016-10-05

This work presents an environmentally friendly, iodine-catalysed chemical modification method to generate highly hydrophobic, optically active cellulose nanocrystals (CNC). The high degree of ester substitution (DS=2.18), hydrophobicity, crystalline behaviour and optical activity of the generated acetylated CNC (Ac-CNC) were quantified by TEM, FTIR, solid 13C NMR, contact angle, XRD and POM analyses. Ac-CNC possessing substantial enhancement in thermal stability (16.8%) and forms thin films with interlayer distance of 50-150 nm, presenting cavities suitable for entrapping nano and micro particles. Generated Ac-CNC proved as an effective reinforcing agent in hydrophobic polymer matrices for fabricating high performance nanocomposites. When integrated at a very low weight percentage (0.5%) in an epoxy matrix, Ac-CNC provided for a 73% increase in tensile strength and a 98% increase in modulus, demonstrating its remarkable reinforcing potential and effective stress transfer behaviour. The method of modification and the unique properties of the modified CNC (hydrophobicity, crystallinity, reinforcing ability and optical activity) render them a novel bionanomaterial for a range of multipurpose applications.

Occupational Noise Reduction in CNC Striping Process

Science.gov (United States)

Mahmad Khairai, Kamarulzaman; Shamime Salleh, Nurul; Razlan Yusoff, Ahmad

2018-03-01

Occupational noise hearing loss with high level exposure is common occupational hazards. In CNC striping process, employee that exposed to high noise level for a long time as 8-hour contributes to hearing loss, create physical and psychological stress that reduce productivity. In this paper, CNC stripping process with high level noises are measured and reduced to the permissible noise exposure. First condition is all machines shutting down and second condition when all CNC machine under operations. For both conditions, noise exposures were measured to evaluate the noise problems and sources. After improvement made, the noise exposures were measured to evaluate the effectiveness of reduction. The initial average noise level at the first condition is 95.797 dB (A). After the pneumatic system with leakage was solved, the noise reduced to 55.517 dB (A). The average noise level at the second condition is 109.340 dB (A). After six machines were gathered at one area and cover that area with plastic curtain, the noise reduced to 95.209 dB (A). In conclusion, the noise level exposure in CNC striping machine is high and exceed the permissible noise exposure can be reduced to acceptable levels. The reduction of noise level in CNC striping processes enhanced productivity in the industry.

Program Design Report of the CNC Machine Tool(II)

International Nuclear Information System (INIS)

Kim, Jong Kiun; Youm, K. U.; Kim, K. S.; Lee, I. B.; Yoon, K. B.; Lee, C. K.; Youm, J. H.

2007-06-01

The application of CNC machine tool being widely expanded according to variety of machine work method and rapid promotion of machine tool, cutting tool, for high speed efficient machine work. In order to conduct of the project of manufacture and maintenance of laboratory equipment, production design and machine work technology are continually developed, especially the application of CNC machine tool is very important for the improvement of productivity, quality and clearing up a manpower shortage. We publish technical report which it includes CNC machine tool program and drawing, it contributes to the systematic development of CNC program design and machine work technology

Program Design Report of the CNC Machine Tool(II)

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Kiun; Youm, K. U.; Kim, K. S.; Lee, I. B.; Yoon, K. B.; Lee, C. K.; Youm, J. H

2007-06-15

The application of CNC machine tool being widely expanded according to variety of machine work method and rapid promotion of machine tool, cutting tool, for high speed efficient machine work. In order to conduct of the project of manufacture and maintenance of laboratory equipment, production design and machine work technology are continually developed, especially the application of CNC machine tool is very important for the improvement of productivity, quality and clearing up a manpower shortage. We publish technical report which it includes CNC machine tool program and drawing, it contributes to the systematic development of CNC program design and machine work technology.

Program Design Report of the CNC Machine Tool(III)

International Nuclear Information System (INIS)

Kim, Jong Kiun; Youm, K. U.; Kim, K. S.; Lee, I. B.; Yoon, K. B.; Lee, C. K.; Youm, J. H.

2008-08-01

The application of CNC machine tool being widely expanded according to variety of machine work method and rapid promotion of machine tool, cutting tool, for high speed efficient machine work. In order to conduct of the project of manufacture and maintenance of laboratory equipment, production design and machine work technology are continually developed, especially the application of CNC machine tool is very important for the improvement of productivity, quality and clearing up a manpower shortage. We publish technical report which it includes CNC machine tool program and drawing, it contributes to the systematic development of CNC program design and machine work technology

Program Design Report of the CNC Machine Tool (I)

International Nuclear Information System (INIS)

Kim, Jong Kiun; Youm, K. U.; Kim, K. S.

2006-08-01

The application of CNC machine tool being widely expanded according to variety of machine work method and rapid promotion of machine tool, cutting tool, for high speed efficient machine work. In order to conduct of the project of manufacture and maintenance of laboratory equipment, production design and machine work technology are continually developed, especially the application of CNC machine tool is very important for the improvement of productivity, quality and clearing up a manpower shortage. We publish technical report which it includes CNC machine tool program and drawing, it contributes to the systematic development of CNC program design and machine work technology

Program Design Report of the CNC Machine Tool(IV)

International Nuclear Information System (INIS)

Youm, Ki Un; Lee, I. B.; Youm, J. H.

2009-09-01

The application of CNC machine tool being widely expanded according to variety of machine work method and rapid promotion of machine tool, cutting tool, for high speed efficient machine work. In order to conduct of the project of manufacture and maintenance of laboratory equipment, production design and machine work technology are continually developed, especially the application of CNC machine tool is very important for the improvement of productivity, quality and clearing up a manpower shortage. We publish technical report which it includes CNC machine tool program and drawing, it contributes to the systematic development of CNC program design and machine work technology

Architecture for Direct Model-to-Part CNC Manufacturing

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Gilbert Poon

2006-02-01

Full Text Available In the traditional paradigm for Computer Numerical Control (CNC machining, tool paths are programmed offline from the CNC machine using the Computer-Aided Design (CAD model of the workpiece. The program is downloaded to the CNC controller and the part is then machined. Since a CAD model does not exist inside the CNC controller, it is unaware of the part to be machined and cannot predict or prevent errors. Not only is this paradigm labor intensive, it can lead to catastrophic damage if there are errors during machining. This paper presents a new concept for CNC machine control whereby a CAD model of the workpiece exists inside the controller and the tool positions are generated in real-time by the controller using the computer's graphics hardware without human intervention. The new concept was implemented on an experimental lathe machine specifically designed to machine complicated ornamental wood workpieces with a personal computer. An example workpiece was machined and measured using a 3D camera. The measured data was registered to the CAD model to evaluate machining accuracy.

CAD/CAM/CNC.

Science.gov (United States)

Domermuth, Dave; And Others

1996-01-01

Includes "Quick Start CNC (computer numerical control) with a Vacuum Filter and Laminated Plastic" (Domermuth); "School and Industry Cooperate for Mutual Benefit" (Buckler); and "CAD (computer-assisted drafting) Careers--What Professionals Have to Say" (Skinner). (JOW)

Comparative study for different statistical models to optimize cutting parameters of CNC end milling machines

International Nuclear Information System (INIS)

El-Berry, A.; El-Berry, A.; Al-Bossly, A.

2010-01-01

In machining operation, the quality of surface finish is an important requirement for many work pieces. Thus, that is very important to optimize cutting parameters for controlling the required manufacturing quality. Surface roughness parameter (Ra) in mechanical parts depends on turning parameters during the turning process. In the development of predictive models, cutting parameters of feed, cutting speed, depth of cut, are considered as model variables. For this purpose, this study focuses on comparing various machining experiments which using CNC vertical machining center, work pieces was aluminum 6061. Multiple regression models are used to predict the surface roughness at different experiments.

Advanced CNC Programming (EZ-CAM). 439-366.

Science.gov (United States)

Casey, Joe

This document contains two units for an advanced course in computer numerical control (CNC) for computer-aided manufacturing. It is intended to familiarize students with the principles and techniques necessary to create proper CNC programs using computer software. Each unit consists of an introduction, instructional objectives, learning materials,…

OPMILL - MICRO COMPUTER PROGRAMMING ENVIRONMENT FOR CNC MILLING MACHINES THREE AXIS EQUATION PLOTTING CAPABILITIES

Science.gov (United States)

Ray, R. B.

1994-01-01

OPMILL is a computer operating system for a Kearney and Trecker milling machine that provides a fast and easy way to program machine part manufacture with an IBM compatible PC. The program gives the machinist an "equation plotter" feature which plots any set of equations that define axis moves (up to three axes simultaneously) and converts those equations to a machine milling program that will move a cutter along a defined path. Other supported functions include: drill with peck, bolt circle, tap, mill arc, quarter circle, circle, circle 2 pass, frame, frame 2 pass, rotary frame, pocket, loop and repeat, and copy blocks. The system includes a tool manager that can handle up to 25 tools and automatically adjusts tool length for each tool. It will display all tool information and stop the milling machine at the appropriate time. Information for the program is entered via a series of menus and compiled to the Kearney and Trecker format. The program can then be loaded into the milling machine, the tool path graphically displayed, and tool change information or the program in Kearney and Trecker format viewed. The program has a complete file handling utility that allows the user to load the program into memory from the hard disk, save the program to the disk with comments, view directories, merge a program on the disk with one in memory, save a portion of a program in memory, and change directories. OPMILL was developed on an IBM PS/2 running DOS 3.3 with 1 MB of RAM. OPMILL was written for an IBM PC or compatible 8088 or 80286 machine connected via an RS-232 port to a Kearney and Trecker Data Mill 700/C Control milling machine. It requires a "D:" drive (fixed-disk or virtual), a browse or text display utility, and an EGA or better display. Users wishing to modify and recompile the source code will also need Turbo BASIC, Turbo C, and Crescent Software's QuickPak for Turbo BASIC. IBM PC and IBM PS/2 are registered trademarks of International Business Machines. Turbo

Structural Reorganization of CNC in Injection-Molded CNC/PBAT Materials under Thermal Annealing.

Science.gov (United States)

Mariano, Marcos; El Kissi, Nadia; Dufresne, Alain

2016-10-04

Composite materials were prepared by extrusion and injection molding from polybutyrate adipate terephthalate (PBAT) and high aspect ratio cellulose nanocrystals (CNCs) extracted from capim dourado fibers. Three CNC contents were used, corresponding to 0.5, 1, and 2 times the theoretical percolation threshold. Small-amplitude oscillary shear (SAOS) experiments show that as the CNC content increases, a more elastic behavior is observed but no percolating network can form within the polymeric matrix as a result of the high shear rates involved during the injection-molding process. Annealing of the samples at 170 °C was performed, and the possible reorganization of the nanofiller was investigated. This reorganization was further elucidated using 2D-SAOS and creep experiments.

Structure and sorption properties of CNC reinforced PVA films.

Science.gov (United States)

Popescu, Maria-Cristina

2017-08-01

Bio-nanocomposite films based on cellulose nanocrystals reinforced poly(vinyl alcohol) were obtained by solvent casting method. To assess the structural features of the films, different spectral techniques (FTIR, 2D COS and XRD) have been used. Infrared and 2D correlation spectroscopy evidenced the presence of H-bond interactions between the PVA and CNC, and the variation in the conformational rearrangements, while XRD showed that the crystallite size and the crystallinity degree were affected by the incorporation of CNC. At low content of CNC in the PVA matrix, the crystallinity degree decreased to 29.9%, while at higher CNC content increased to 80.6%, comparing to PVA (35.4%). To evaluate the interaction with water, contact angle measurement, water sorption and NIR spectroscopy were used, respectively. The increase of the CNC content induced a reduction in water sorption ability from 93% for PVA to 75% for PVA/CNC films, indicating the involvement of the hydroxyl groups in new hydrogen bonded interactions. By analyzing the variation of the NIR bands from 1930, 1902 and 1985nm, was observed that the water molecules interact with the polymer matrix through moderate hydrogen bond before diffusing into the free volume of the matrix and form stronger hydrogen bonds. Copyright © 2017 Elsevier B.V. All rights reserved.

On the polymorphic and morphological changes of cellulose nanocrystals (CNC-I) upon mercerization and conversion to CNC-II.

Science.gov (United States)

Jin, Ersuo; Guo, Jiaqi; Yang, Fang; Zhu, Yangyang; Song, Junlong; Jin, Yongcan; Rojas, Orlando J

2016-06-05

Polymorphic and morphological transformations of cellulosic materials are strongly associated to their properties and applications, especially in the case of emerging nanocelluloses. Related changes that take place upon treatment of cellulose nanocrystals (CNC) in alkaline conditions are studied here by XRD, TEM, AFM, and other techniques. The results indicate polymorphic transformation of CNC proceeds gradually in a certain range of alkali concentrations, i.e. from about 8% to 12.5% NaOH. In such transition alkali concentration, cellulose I and II allomorphs coexists. Such value and range of the transition concentration is strongly interdependent with the crystallite size of CNCs. In addition, it is distinctively lower than that for macroscopic fibers (12-15% NaOH). Transmission electron microscopy and particle sizing reveals that after mercerization CNCs tend to associate. Furthermore, TEMPO-oxidized mercerized CNC reveals the morphology of individual nanocrystal of the cellulose II type, which is composed of some interconnected granular structures. Overall, this work reveals how the polymorphism and morphology of individual CNC change in alkali conditions and sheds light onto the polymorphic transition from cellulose I to II. Copyright © 2016 Elsevier Ltd. All rights reserved.

Program Design Report of the CNC Machine Tool(V-1)

International Nuclear Information System (INIS)

Youm, Ki Un; Moon, J. S.; Lee, I. B.; Youn, J. H.

2010-08-01

The application of CNC machine tool being widely expanded according to variety of machine work method and rapid promotion of machine tool, cutting tool, for high speed efficient machine work. In order to conduct of the project of manufacture and maintenance of laboratory equipment, production design and machine work technology are continually developed, especially the application of CNC machine tool is very important for the improvement of productivity, quality and clearing up a manpower shortage. We publish technical report which it includes CNC machine tool program and drawing, it contributes to the systematic development of CNC program design and machine work technology

Concept of a Programmable Fixture for 3-Axis CNC

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Ahmad Dalloul

2017-09-01

Full Text Available CNC machine is the one of the major reasons for industrial advancement in recent decades for its ability of producing accurate parts. The most commen CNC machines are of 3-axis and adopted widely in the industrial sector. However, for producing more complicated parts 5-axis CNC machines are required. Although the introduction of the 5-axis machine came after the 3-axis CNC machine has established itself and many manufacturers did not make the move toward the newer model and its high pricing compared to the 3-axis model did not help either. In this time the development of a fixture or a platform to help transfer the 3-axis to a 5-axis to some degree. This paper discusses the concept of a programmable fixture that gives 3-axis CNC machine the freedom to act in similar manner as the 5-axis. The paper describes the mechanism with some initial results of the testing. Result showed that the platform moves in translation manner with an average error of 5.58 % and 7.303% average error for rotation movement.

Design and milling manufacture of polyurethane custom contoured cushions for wheelchair users

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Wilson Kindlein Junior

2011-09-01

Full Text Available BackgroundThe design of custom contoured cushions manufactured inflexible polyurethane foams is an option to improvepositioning and comfort for people with disabilities thatspend most of the day seated in the same position. Thesesurfaces increase the contact area between the seat and theuser. This fact contributes to minimise the local pressuresthat can generate problems like decubitus ulcers. Thepresent research aims at establishing development routesfor custom cushion production to wheelchair users. Thisstudy also contributes to the investigation of ComputerNumerical Control (CNC machining of flexible polyurethanefoams.MethodThe proposed route to obtain the customised seat beganwith acquiring the user’s contour in adequate posturethrough plaster cast. To collect the surface geometry, thecast was three-dimensionally scanned and manipulated inCAD/CAM software. CNC milling parameters such as tools,spindle speeds and feed rates to machine flexiblepolyurethane foams were tested. These parameters wereanalysed regarding the surface quality. The best parameterswere then tested in a customised seat. The possibledimensional changes generated during foam cutting wereanalysed through 3D scanning. Also, the customised seatpressure and temperature distribution was tested.ResultsThe best parameters found for foams with a density of50kg/cm3 were high spindle speeds (24000 rpm and feedrates between 2400–4000mm/min. Those parameters didnot generate significant deformities in the machinedcushions. The custom contoured cushion satisfactorilyincreased the contact area between wheelchair and user, asit distributed pressure and heat evenly.ConclusionThrough this study it was possible to define routes for thedevelopment and manufacturing of customised seats usingdirect CNC milling in flexible polyurethane foams. It alsoshowed that custom contoured cushions efficientlydistribute pressure and temperature, which is believed tominimise tissue lesions such as pressure

Lutidine-derived Ru-CNC hydrogenation pincer catalysts with versatile coordination properties

NARCIS (Netherlands)

Filonenko, Georgy A.; Cosimi, Elena; Lefort, Laurent; Conley, Matthew P.; Copéret, Christophe; Lutz, Martin; Hensen, Emiel J M; Pidko, Evgeny A.

2014-01-01

Lutidine-derived bis-N-heterocyclic carbene (NHC) ruthenium CNC-pincer complexes (Ru-CNC's) were prepared. Depending on the synthetic procedure, normal (1, 2) or mixed normal/abnormal NHC-complexes (3) are formed. In the presence of phosphazene base, Ru-CNC complexes activate nitriles to give

Experimental High Speed Milling of the Selected Thin-Walled Component

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Jozef Zajac

2017-11-01

Full Text Available In a technical practice, it is possible to meet thin-walled parts more and more often. These parts are most commonly used in the automotive industry or aircraft industry to reduce the weight of different design part of cars or aircraft. Presented article is focused on experimental high speed milling of selected thin-walled component. The introduction of this article presents description of high speed machining and specification of thin – walled parts. The experiments were carried out using a CNC machine Pinnacle VMC 650S and C45 material - plain carbon steel for automotive components and mechanical engineering. In the last part of the article, described are the arrangements to reduction of deformation of thin-walled component during the experimental high speed milling.

Neurotensin-loaded PLGA/CNC composite nanofiber membranes accelerate diabetic wound healing.

Science.gov (United States)

Zheng, Zhifang; Liu, Yishu; Huang, Wenhua; Mo, Yunfei; Lan, Yong; Guo, Rui; Cheng, Biao

2018-04-13

Diabetic foot ulcers (DFUs) are a threat to human health and can lead to amputation and even death. Recently neurotensin (NT), an inflammatory modulator in wound healing, was found to be beneficial for diabetic wound healing. As we demonstrated previously, polylactide-polyglycolide (PLGA) and cellulose nanocrystals (CNCs) (PLGA/CNC) nanofiber membranes show good cytocompatibility and facilitate fibroblast adhesion, spreading and proliferation. PLGA/CNC nanofiber membranes are novel materials that have not been used previously as NT carriers in diabetic wounds. This study aims to explore the therapeutic efficacy and possible mechanisms of NT-loaded PLGA/CNC nanofiber membranes in full-thickness skin wounds in spontaneously diabetic mice. The results showed that NT could be sustained released from NT-loaded PLGA/CNC composite nanofiber membranes for 2 weeks. NT-loaded PLGA/CNC composite nanofiber membranes induced more rapid healing than other control groups. After NT exposure, the histological scores of the epidermal and dermal regeneration and the ratios of the fibrotic area to the whole area were increased. NT-loaded PLGA/CNC composite nanofiber membranes also decreased the expressions of the inflammatory cytokines IL-1β and IL-6. These results suggest that NT-loaded PLGA/CNC composite nanofiber membranes for sustained delivery of NT should effectively promote tissue regeneration for the treatment of DFUs.

DIAGNOSTIC OF CNC LATHE WITH QC 20 BALLBAR SYSTEM

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Jerzy Józwik

2015-11-01

Full Text Available This paper presents the evaluation of the influence of the feedmotion speed on the value of selected geometric errors of CNC lathe CTX 310 eco by DMG, indentified by QC 20 Ballbar system. Diagnostically evaluated were: the deviation of the axis squareness, reversal spike, and backlash. These errors determine the forming of the dimensional and shape accuracy of a machine tool. The article discusses the process of the CNC diagnostic test, the diagnostic evaluation and formulates guidelines on further CNC operation. The results of measurements were presented in tables and diagrams.

Integration of CAM and CNC operation through code editing and manipulation

International Nuclear Information System (INIS)

Rosli Darmawan; Shalina Sheik Muhammad

2004-01-01

The IT technology for engineering design and manufacturing has gone through significant advancement for the last 30 years. It is widely acknowledged that IT would provide competitive advantage for engineering company in term of production cycle, productivity and efficiency. The recent development in this area is on the total system integration. While standard off-shelf CAD/CAM/CNC software and hardware packages would provide solution for system integration, more often than not users will stumble upon compatibility problems. Moreover, most of the integration deals with CAD and CAM systems. CNC integration has not been fully developed. Users always found problems in the integration of CAM and CNC machine due to the different level of technological development. CNC codes have not fundamentally progressed in the last 50 years, while CAD/CAM software packages have undergone massive evolution and improvement. This paper discusses a practical solution of CAM and CNC integration through code editing and manipulation within the CAM system in order to comply with the CNC machine requirements. (Author)

Complex Ornament Machining Process on a CNC Router

Directory of Open Access Journals (Sweden)

Camelia COŞEREANU

2014-03-01

Full Text Available The paper investigates the CNC routering possibilities for three species of wood, namely ash (Fraxinus Excelsior, lime wood (Tilia cordata and fir wood (Abies Alba, in order to obtain right surfaces of Art Nouveau sculptured ornaments. Given the complexity of the CNC tool path for getting wavy shapes of Art Nouveau decorations, the choice of processing parameters for each processed species of wood requires a laborious research work to correlate these parameters. Two Art Nouveau ornaments are proposed for the investigation. They are CNC routered using two types of cutting tools. The processed parameters namely the spindle speed, feed speed and depth of cut were the three variables of the machining process for the three species of wood, which were combined so, to provide good surface finish as a quality attribute. There were totally forty six variants of combining the processing parameter which were applied for CNC routering the samples made of the three species of wood. At the end, an optimum combination of the processed parameters is recommended for each species of wood.

Micromilling: a method for ultra-rapid prototyping of plastic microfluidic devices.

Science.gov (United States)

Guckenberger, David J; de Groot, Theodorus E; Wan, Alwin M D; Beebe, David J; Young, Edmond W K

2015-06-07

This tutorial review offers protocols, tips, insight, and considerations for practitioners interested in using micromilling to create microfluidic devices. The objective is to provide a potential user with information to guide them on whether micromilling would fill a specific need within their overall fabrication strategy. Comparisons are made between micromilling and other common fabrication methods for plastics in terms of technical capabilities and cost. The main discussion focuses on "how-to" aspects of micromilling, to enable a user to select proper equipment and tools, and obtain usable microfluidic parts with minimal start-up time and effort. The supplementary information provides more extensive discussion on CNC mill setup, alignment, and programming. We aim to reach an audience with minimal prior experience in milling, but with strong interests in fabrication of microfluidic devices.

Effect of Stiffness of Rolling Joints on the Dynamic Characteristic of Ball Screw Feed Systems in a Milling Machine

Directory of Open Access Journals (Sweden)

Dazhong Wang

2015-01-01

Full Text Available Dynamic characteristic of ball screw feed system in a milling machine is studied numerically in this work. In order to avoid the difficulty in determining the stiffness of rolling joints theoretically, a dynamic modeling method for analyzing the feed system is discussed, and a stiffness calculation method of the rolling joints is proposed based on the Hertz contact theory. Taking a 3-axis computer numerical control (CNC milling machine set ermined as a research object, the stiffness of its fixed joint between the column and the body together with the stiffness parameters of the rolling joints is evaluated according to the Takashi Yoshimura method. Then, a finite element (FE model is established for the machine tool. The correctness of the FE model and the stiffness calculation method of the rolling joints are validated by theoretical and experimental modal analysis results of the machine tool’s workbench. Under the two modeling methods of joints incorporating the stiffness parameters and rigid connection, a theoretical modal analysis is conducted for the CNC milling machine. The natural frequencies and modal shapes reveal that the joints’ dynamic characteristic has an important influence on the dynamic performance of a whole machine tool, especially for the case with natural frequency and higher modes.

Fully automatic CNC machining production system

Directory of Open Access Journals (Sweden)

Lee Jeng-Dao

2017-01-01

Full Text Available Customized manufacturing is increasing years by years. The consumption habits change has been cause the shorter of product life cycle. Therefore, many countries view industry 4.0 as a target to achieve more efficient and more flexible automated production. To develop an automatic loading and unloading CNC machining system via vision inspection is the first step in industrial upgrading. CNC controller is adopted as the main controller to command to the robot, conveyor, and other equipment in this study. Moreover, machine vision systems are used to detect position of material on the conveyor and the edge of the machining material. In addition, Open CNC and SCADA software will be utilized to make real-time monitor, remote system of control, alarm email notification, and parameters collection. Furthermore, RFID has been added to employee classification and management. The machine handshaking has been successfully proposed to achieve automatic vision detect, edge tracing measurement, machining and system parameters collection for data analysis to accomplish industrial automation system integration with real-time monitor.

Design and milling manufacture of polyurethane custom contoured cushions for wheelchair users.

Science.gov (United States)

da Silva, Fabio Pinto; Beretta, Elisa Marangon; Prestes, Rafael Cavalli; Kindlein Junior, Wilson

2011-01-01

The design of custom contoured cushions manufactured in flexible polyurethane foams is an option to improve positioning and comfort for people with disabilities that spend most of the day seated in the same position. These surfaces increase the contact area between the seat and the user. This fact contributes to minimise the local pressures that can generate problems like decubitus ulcers. The present research aims at establishing development routes for custom cushion production to wheelchair users. This study also contributes to the investigation of Computer Numerical Control (CNC) machining of flexible polyurethane foams. The proposed route to obtain the customised seat began with acquiring the user's contour in adequate posture through plaster cast. To collect the surface geometry, the cast was three-dimensionally scanned and manipulated in CAD/CAM software. CNC milling parameters such as tools, spindle speeds and feed rates to machine flexible polyurethane foams were tested. These parameters were analysed regarding the surface quality. The best parameters were then tested in a customised seat. The possible dimensional changes generated during foam cutting were analysed through 3D scanning. Also, the customised seat pressure and temperature distribution was tested. The best parameters found for foams with a density of 50kg/cm(3) were high spindle speeds (24000 rpm) and feed rates between 2400-4000mm/min. Those parameters did not generate significant deformities in the machined cushions. The custom contoured cushion satisfactorily increased the contact area between wheelchair and user, as it distributed pressure and heat evenly. Through this study it was possible to define routes for the development and manufacturing of customised seats using direct CNC milling in flexible polyurethane foams. It also showed that custom contoured cushions efficiently distribute pressure and temperature, which is believed to minimise tissue lesions such as pressure ulcers.

IL web tutorials

DEFF Research Database (Denmark)

Hyldegård, Jette; Lund, Haakon

2012-01-01

The paper presents the results from a study on information literacy in a higher education (HE) context based on a larger research project evaluating 3 Norwegian IL web tutorials at 6 universities and colleges in Norway. The aim was to evaluate how the 3 web tutorials served students’ information...... seeking and writing process in an study context and to identify barriers to the employment and use of the IL web tutorials, hence to the underlying information literacy intentions by the developer. Both qualitative and quantitative methods were employed. A clear mismatch was found between intention...... and use of the web tutorials. In addition, usability only played a minor role compared to relevance. It is concluded that the positive expectations of the IL web tutorials tend to be overrated by the developers. Suggestions for further research are presented....

Repurposing mainstream CNC machine tools for laser-based additive manufacturing

Science.gov (United States)

Jones, Jason B.

2016-04-01

The advent of laser technology has been a key enabler for industrial 3D printing, known as Additive Manufacturing (AM). Despite its commercial success and unique technical capabilities, laser-based AM systems are not yet able to produce parts with the same accuracy and surface finish as CNC machining. To enable the geometry and material freedoms afforded by AM, yet achieve the precision and productivity of CNC machining, hybrid combinations of these two processes have started to gain traction. To achieve the benefits of combined processing, laser technology has been integrated into mainstream CNC machines - effectively repurposing them as hybrid manufacturing platforms. This paper reviews how this engineering challenge has prompted beam delivery innovations to allow automated changeover between laser processing and machining, using standard CNC tool changers. Handling laser-processing heads using the tool changer also enables automated change over between different types of laser processing heads, further expanding the breadth of laser processing flexibility in a hybrid CNC. This paper highlights the development, challenges and future impact of hybrid CNCs on laser processing.

ANALYSIS OF CUTTING FORCES ON CNC LATHES EXPERIMENTAL APPROACH

Directory of Open Access Journals (Sweden)

Erdem Koç

1996-01-01

Full Text Available Objective of this study is to make use easy programming of CNC lathes and to achieve the optimization of part program prepared considering the limiting parameters of the machine. In the present study, a BOXFORD 250 B CNC lathe has been used for experiment and optimization process. The measurement of cutting forces exerted on the cutting tool of CNC lathe has been performed. The cutting forces occurring during the turning operation have been determined for different depth of" cut, feed rate and cutting speed as well as different cutting tools and related data base has been obtained.

Making generic tutorials content specific: recycling evidence-based practice (EBP) tutorials for two disciplines.

Science.gov (United States)

Jeffery, Keven M; Maggio, Lauren; Blanchard, Mary

2009-01-01

Librarians at the Boston University Medical Center constructed two interactive online tutorials, "Introduction to EBM" and "Formulating a Clinical Question (PICO)," for a Family Medicine Clerkship and then quickly repurposed the existing tutorials to support an Evidence-based Dentistry course. Adobe's ColdFusion software was used to populate the tutorials with course-specific content based on the URL used to enter each tutorial, and a MySQL database was used to collect student input. Student responses were viewable immediately by course faculty on a password-protected Web site. The tutorials ensured that all students received the same baseline training and allowed librarians to tailor a subsequent library skills workshop to student tutorial answers. The tutorials were well-received by the medical and dental schools and have been added to mandatory first-year Evidence-based Medicine (EBM) and Evidence-based Dentistry (EBD) courses, meaning that every medical and dental student at BUMC will be expected to complete these tutorials.

INTEGRASI SOFTWARE CAD-CAM DALAM SISTEM OPERASI MESIN BUBUT CNC

Directory of Open Access Journals (Sweden)

Yuris Setyoadi

2015-12-01

Full Text Available Computer Aided Manufacturing (CAM adalah sebuah teknologi aplikasi yang menggunakan perangkat lunak komputer dan mesin untuk memfasilitasi dan mengotomatisasi proses manufaktur. Computer Aided Manufacturing (CAM adalah penerus dari Computer Aided Engineering (CAE dan sering digunakan bersama dengan Computer-Aided Design (CAD. Bidang manufaktur, perangkat komputer telah dipergunakan untuk mengontrol mesin-mesin produksi otomatis dengan ketepatan tinggi, misalnya mesin CNC. ?é?áArtikel ini membahas tentang penggunaan software CAD-CAM (SOLIDWorks dan CAMWorks yang terintegrasi kemudian diaplikasikan ke mesin bubut CNC yang menggunakan software Mach3, Mach3 adalah software yang bisa mengubah komputer dekstop menjadi sebuah piranti kontroller mesin CNC. Software SOLIDWorks, CAMWorks dan Mach3 diintegrasikan ke dalam sistem operasi mesin bubut CNC sehingga proses koreksi dan modifikasi format perintah gerakan dalam G/M code dapat dilakukan dalam software tersebut.

Vyhodnocení CNC stroje versus konvenční stroj ve firmě

OpenAIRE

Kopecký, Štěpán

2016-01-01

Bakalářská práce se zabývá analýzou CNC stroje ve firmě a porovnáním CNC oproti konvenčnímu stroji. Analýza CNC se zaměřuje na ekonomické přínosy a přínosy pro firmu z hlediska zlepšení produktivity a přesnosti. Po prostudování odborné literatury a seznámením se s CNC frézou a jejím řídicím systémem a konvenčními stroji firmy Alubra s.r.o. je porovnán výrobek. Bachelor thesis describes analysis of CNC machine in company. The analysis of CNC machine focus on economical benefits and compare ...

CNC LATHE MACHINE PRODUCING NC CODE BY USING DIALOG METHOD

Directory of Open Access Journals (Sweden)

Yakup TURGUT

2004-03-01

Full Text Available In this study, an NC code generation program utilising Dialog Method was developed for turning centres. Initially, CNC lathes turning methods and tool path development techniques were reviewed briefly. By using geometric definition methods, tool path was generated and CNC part program was developed for FANUC control unit. The developed program made CNC part program generation process easy. The program was developed using BASIC 6.0 programming language while the material and cutting tool database were and supported with the help of ACCESS 7.0.

Determination of the Tapping Part Diameter of the Thread Mill

Directory of Open Access Journals (Sweden)

A. E. Dreval'

2015-01-01

Full Text Available Currently, there is a tendency to increase the proportion of thread milling operations, among other ways of tapping, which is associated with increasing number of CNC machines, flexibility and versatility of the process.Developments presently existing in the RF and used in the thread mills deal, mainly, with the thread milling cutter designs, to process internal and external thread with straight flutes made from high-speed steel.The paper presents a technique to calculate and select the initial design parameters, i.e. the external diameter of the tapping part of thread milling cutter, which is chosen as a basic computational design. The analysis of directories of tool companies containing foreign de-signs of solid thread end-milling cutters has shown that most of them rep-resent the thread cutter designs made of solid carbide. There are solid and interlocking side milling cutters, which use a tapping part both as a single-disk and as a multi-disk one; chip flutes are made to be both as direct and as screw; solid designs of cutters are made from carbide with a diameter of up to 20 ... 25 mm; thread cutters can be left- and right-hand cutting; Designs of the combined thread mills are proposed; internal channels are used for coolant supply.It is shown that the purpose of the external diameter of the tapping part of the thread mill should take into account the effect of the thread mill diameter on the milling process performance, precision of thread profile received, taper thread, tool strength, and the volume of flutes.The analysis has shown that when choosing the external diameter of the thread mill it worth taking its maximum diameter to improve the char-acteristics of the process under the restrictions imposed on the accuracy of the formed thread.

Fuzzy Control Tutorial

DEFF Research Database (Denmark)

Dotoli, M.; Jantzen, Jan

1999-01-01

The tutorial concerns automatic control of an inverted pendulum, especially rule based control by means of fuzzy logic. A ball balancer, implemented in a software simulator in Matlab, is used as a practical case study. The objectives of the tutorial are to teach the basics of fuzzy control......, and to show how to apply fuzzy logic in automatic control. The tutorial is distance learning, where students interact one-to-one with the teacher using e-mail....

Implementation of the geometrical problem in CNC metal cutting machine

Directory of Open Access Journals (Sweden)

Erokhin V.V.

2017-06-01

Full Text Available The article deals with the tasks of managing the production process (technological process and technological equip-ment, the most detailed analysis of the implementation of the geometric problem in CNC machines. The influence of the solution of the geometric CNC problem on the accuracy of workpiece machining is analyzed by implementing a certain interpolation algorithm and the values of the discreteness of the movements of the working bodies of the CNC machine. The technique of forming a given trajectory of motion of the machine's executive organ is given, by means of which it is required to ensure the coordinated movement of the shaping coordinates according to a certain law, depend-ing on the specified trajectory of the cutting edge of the tool. The advantages and disadvantages of the implementation of interpolation in CNC systems by various methods are considered, and particular attention is paid to combined meth-ods of realizing interpolation.

Generating Consistent Program Tutorials

DEFF Research Database (Denmark)

Vestdam, Thomas

2002-01-01

In this paper we present a tool that supports construction of program tutorials. A program tutorial provides the reader with an understanding of an example program by interleaving fragments of source code and explaining text. An example program can for example illustrate how to use a library or a......, and we see potential in using the tool to produce program tutorials to be used for frameworks, libraries, and in educational contexts.......In this paper we present a tool that supports construction of program tutorials. A program tutorial provides the reader with an understanding of an example program by interleaving fragments of source code and explaining text. An example program can for example illustrate how to use a library...... or a framework. We present a means for specifying the fragments of a program that are to be in-lined in the tutorial text. These in-line fragments are defined by addressing named syntactical elements, such as classes and methods, but it is also possible to address individual code lines by labeling them...

Application of Ethernet Powerlink for communication in a Linux RTAI open CNC control system

OpenAIRE

Erwiński, Krystian; Paprocki, Marcin; Grzesiak, Lech; Karwowski, Kazimierz; Wawrzak, Andrzej

2013-01-01

In computerized numerical control (CNC) systems, the communication bus between the controller and axis servo drives must offer high bandwidth, noise immunity, and time determinism. More and more CNC systems use real-time Ethernet protocols such as Ethernet Powerlink (EPL). Many modern controllers are closed costly hardware-based solutions. In this paper, the implementation of EPL communication bus in a PC-based CNC system is presented. The CNC system includes a PC, a s...

Modelling of End Milling of AA6061-TiCp Metal Matrix Composite

Science.gov (United States)

Vijay Kumar, S.; Cheepu, Muralimohan; Venkateswarlu, D.; Asohan, P.; Senthil Kumar, V.

2018-03-01

The metal-matrix composites (MMCs) are used in various applications hence lot of research has been carried out on MMCs. To increase the properties of Al-based MMCs many ceramic reinforcements have been identified, among which TiC is played vital role because of its properties like high hardness, stiffness and wear resistance. In the present work, a neural network and statistical modelling approach is going to use for the prediction of surface roughness (Ra) and cutting forces in computerised numerical control milling machine. Experiments conducted on a CNC milling machine based on the full factorial design and resulted data used to train and checking the network performance. The sample prepared from in-situ technique and heat treated to get uniform properties. The ANN model has shown satisfactory performance comparatively.

Tool wear in terms of vibration effects in milling medium-density fibreboard with an industrial robot

International Nuclear Information System (INIS)

Tratar, Janez; Pusavec, Franci; Kopac, Janez

2014-01-01

Machining with robots represents a promising, highly flexible and cost effective alternative to standard machining and hand labour applications when machining mid tolerance soft material end products. One of the most challenging issues is to know the vibration characteristics in milling with the robots which greatly affect tool life. In general the technological bases of tool life expectancy while milling with robot arms are not available or studied. That's why the purpose of this paper is to investigate the influence of attained vibrations analysis during the milling process and correlated tool wear. Primarily the study is focused on tool wear according to the distance between the milling position and the robot's base. Results show that increasing distance between the robot's base and the milling position significantly affects tool wear because of the attained vibrations in proportion to the increasing distance respectively. Tool wear has also proved to be greater in comparison to machining with CNC machine and applicable new information for woodworking industry.

Creating library tutorials for nursing students.

Science.gov (United States)

Schroeder, Heidi

2010-04-01

This article describes one librarian's experiences with creating, promoting, and assessing online library tutorials. Tutorials were designed to provide on-demand and accessible library instruction to nursing students at Michigan State University. Topics for tutorials were chosen based on the librarian's liaison experiences and suggestions from nursing faculty. The tutorials were created using Camtasia and required the application of several tools and techniques. Tutorials were promoted through Web pages, the ANGEL course management system, blog posts, librarian interactions, e-mails, and more. In order to assess the tutorials' perceived effectiveness, feedback was gathered using a short survey. Future plans for the nursing tutorials project are also discussed.

Research on Key Technologies of Unit-Based CNC Machine Tool Assembly Design

OpenAIRE

Zhongqi Sheng; Lei Zhang; Hualong Xie; Changchun Liu

2014-01-01

Assembly is the part that produces the maximum workload and consumed time during product design and manufacturing process. CNC machine tool is the key basic equipment in manufacturing industry and research on assembly design technologies of CNC machine tool has theoretical significance and practical value. This study established a simplified ASRG for CNC machine tool. The connection between parts, semantic information of transmission, and geometric constraint information were quantified to as...

Effect of CNC-milling on the marginal and internal fit of dental ceramics: a pilot study.

Science.gov (United States)

Schaefer, Oliver; Kuepper, Harald; Thompson, Geoffrey A; Cachovan, Georg; Hefti, Arthur F; Guentsch, Arndt

2013-08-01

Machined restorations have been investigated for their preciseness before, while detailed information on the milling-step itself are lacking. Therefore, the aim of this laboratory study was to quantify the effect of a novel milling-procedure on the marginal and internal fit of ceramic restorations. An acrylic model of a lower left first molar was prepared to receive a ceramic partial crown and was duplicated by one step dual viscosity impressions. Gypsum casts were formed and laser-scanned to realize virtual datasets, before restorations were designed, exported (PRE) and machined from lithium disilicate blanks. Crowns were digitized by a structure-light-scanner to obtain post-milling-data (POST). PRE and POST were virtually superimposed on the reference tooth and subjected to computer-aided-inspection. Visual fit-discrepancies were displayed with colors, while root mean square deviations (RMSD) and degrees of similarity (DS) were computed and analysed by t-tests for paired samples (n=5, α=0.05). The milling procedure resulted in a small increase of the marginal and internal fit discrepancies (RMSD mean: 3μm and 6μm, respectively). RMSD differences were not statistically significant (p=0.495 and p=0.160 for marginal and internal fit, respectively). These results were supported by the DS data. The products of digital dental workflows are prone to imprecisions. However, the present findings suggest that differences between computer-aided designed and actually milled restorations are small, especially when compared to typical fit discrepancies observed clinically. Imprecisions introduced by digital design or production processes are small. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

3D-printed and CNC milled flow-cells for chemiluminescence detection.

Science.gov (United States)

Spilstead, Kara B; Learey, Jessica J; Doeven, Egan H; Barbante, Gregory J; Mohr, Stephan; Barnett, Neil W; Terry, Jessica M; Hall, Robynne M; Francis, Paul S

2014-08-01

Herein we explore modern fabrication techniques for the development of chemiluminescence detection flow-cells with features not attainable using the traditional coiled tubing approach. This includes the first 3D-printed chemiluminescence flow-cells, and a milled flow-cell designed to split the analyte stream into two separate detection zones within the same polymer chip. The flow-cells are compared to conventional detection systems using flow injection analysis (FIA) and high performance liquid chromatography (HPLC), with the fast chemiluminescence reactions of an acidic potassium permanganate reagent with morphine and a series of adrenergic phenolic amines. Copyright © 2014 Elsevier B.V. All rights reserved.

Researches regarding the reducing of burr size by optimising the cutting parameters on a CNC milling machine

Directory of Open Access Journals (Sweden)

Biriş Cristina

2017-01-01

Full Text Available This paper presents some experimental researches regarding burrs dimensions reduction that appear after the milling process together with an approach to reduce or eliminate the burrs resulted after this process. In order to reduce burrs dimensions, the milling process was executed with different cutting parameters and strategies then the results were evaluated.

Fuzzy Linguistic Optimization on Surface Roughness for CNC Turning

OpenAIRE

Lan, Tian-Syung

2010-01-01

Surface roughness is often considered the main purpose in contemporary computer numerical controlled (CNC) machining industry. Most existing optimization researches for CNC finish turning were either accomplished within certain manufacturing circumstances or achieved through numerous equipment operations. Therefore, a general deduction optimization scheme is deemed to be necessary for the industry. In this paper, the cutting depth, feed rate, speed, and tool nose runoff with low, medium, and...

Research on Key Technologies of Unit-Based CNC Machine Tool Assembly Design

Directory of Open Access Journals (Sweden)

Zhongqi Sheng

2014-01-01

Full Text Available Assembly is the part that produces the maximum workload and consumed time during product design and manufacturing process. CNC machine tool is the key basic equipment in manufacturing industry and research on assembly design technologies of CNC machine tool has theoretical significance and practical value. This study established a simplified ASRG for CNC machine tool. The connection between parts, semantic information of transmission, and geometric constraint information were quantified to assembly connection strength to depict the assembling difficulty level. The transmissibility based on trust relationship was applied on the assembly connection strength. Assembly unit partition based on assembly connection strength was conducted, and interferential assembly units were identified and revised. The assembly sequence planning and optimization of parts in each assembly unit and between assembly units was conducted using genetic algorithm. With certain type of high speed CNC turning center, as an example, this paper explored into the assembly modeling, assembly unit partition, and assembly sequence planning and optimization and realized the optimized assembly sequence of headstock of CNC machine tool.

An Investigation of the Potential Antifungal Properties of CNC-2 in Caenorhabditis elegans.

Science.gov (United States)

Zehrbach, Angelina M D; Rogers, Alexandra R; Tarr, D Ellen K

2017-12-01

Caenorhabditis elegans responds to infections by upregulating specific antimicrobial peptides. The caenacin-2 ( cnc-2 ) gene is consistently upregulated in C. elegans by infection with the filamentous fungus Drechmeria coniospora , but there have been no direct studies of the CNC-2 peptide's in vivo or in vitro role in defending the nematode against this pathogen. We compared infection of wild-type and cnc-2 knockout nematode strains with four potential pathogens: D. coniospora , Candida albicans , Staphylococcus aureus , and Bacillus subtilis . There was no significant difference in survival between strains for any of the pathogens or on the maintenance strain of Escherichia coli . While we were unable to demonstrate definitively that CNC-2 is integral to fungal defenses in C. elegans , we identified possible explanations for these results as well as future work that is needed to investigate CNC-2's potential as a new antifungal treatment.

Hygroscopic Swelling Determination of Cellulose Nanocrystal (CNC) Films by Polarized Light Microscopy Digital Image Correlation.

Science.gov (United States)

Shrestha, Shikha; Diaz, Jairo A; Ghanbari, Siavash; Youngblood, Jeffrey P

2017-05-08

The coefficient of hygroscopic swelling (CHS) of self-organized and shear-oriented cellulose nanocrystal (CNC) films was determined by capturing hygroscopic strains produced as result of isothermal water vapor intake in equilibrium. Contrast enhanced microscopy digital image correlation enabled the characterization of dimensional changes induced by the hygroscopic swelling of the films. The distinct microstructure and birefringence of CNC films served in exploring the in-plane hygroscopic swelling at relative humidity values ranging from 0% to 97%. Water vapor intake in CNC films was measured using dynamic vapor sorption (DVS) at constant temperature. The obtained experimental moisture sorption and kinetic profiles were analyzed by fitting with Guggenheim, Anderson, and deBoer (GAB) and Parallel Exponential Kinetics (PEK) models, respectively. Self-organized CNC films showed isotropic swelling, CHS ∼0.040 %strain/%C. By contrast, shear-oriented CNC films exhibited an anisotropic swelling, resulting in CHS ∼0.02 and ∼0.30 %strain/%C, parallel and perpendicular to CNC alignment, respectively. Finite element analysis (FEA) further predicted moisture diffusion as the predominant mechanism for swelling of CNC films.

The influence of milling-burnishing successive and simultaneous processes on the material hardness

Science.gov (United States)

Grigoraş, C. C.; Brabie, G.; Chirita, B.

2016-08-01

Recent developments in the field of bio-engineering allow the use of magnesium alloys as a substitute for medical implants. The issue with such alloys is the degradation rate witch has to be improved in order to provide the necessary support for the entire duration of the bone fraction healing. For improving the bone shielding heat treatment does not represent a solution, but chemical and/or mechanical do. One mechanical process that has excellent result is burnishing, but this process is difficult to be implemented on a milling machine. Therefore, it was necessary that a new tool and tool holder to be developed, that allow the simultaneous process to take place. A high-pressure hydraulic roller burnishing tool with a special tool holder was used on a CNC milling machine. The material used for this study is magnesium alloy AZ31B-F, and one of the main purposes was to improve the material hardness (HV). The milling-burnishing parameters that where varied are the speed and feed, burnishing pressure and depth, type of process (successive or simultaneous), machining direction and the material hardness after milling. The results were analyzed as percentage improvement between the milling and burnishing measured values.

EFFECTIVE ELECTRONIC TUTORIAL

Directory of Open Access Journals (Sweden)

Andrei A. Fedoseev

2014-01-01

Full Text Available The article analyzes effective electronic tutorials creation and application based on the theory of pedagogy. Herewith the issues of necessary electronic tutorial functional, ways of the educational process organization with the use of information and communication technologies and the logistics of electronic educational resources are touched upon. 

In-situ polymerized cellulose nanocrystals (CNC)-poly(l-lactide) (PLLA) nanomaterials and applications in nanocomposite processing.

Science.gov (United States)

Miao, Chuanwei; Hamad, Wadood Y

2016-11-20

CNC-PLLA nanomaterials were synthesized via in-situ ring-opening polymerization of l-lactide in the presence of CNC, resulting in hydrophobic, homogeneous mixture of PLLA-grafted-CNC and free PLLA homopolymer. The free PLLA serves two useful functions: as barrier to further prevent PLLA-g-CNC from forming aggregates, and in creating improved interfacial properties when these nanomaterials are blended with other polymers, hence enhancing their performance. CNC-PLLA nanomaterials can be used for medical or engineering applications as-they-are or by compounding with suitable biopolymers using versatile techniques, such as solution casting, co-extrusion or injection molding, to form hybrid nanocomposites of tunable mechanical properties. When compounded with commercial-grade PLA, the resulting CNC-PLA nanocomposites appear transparent and have tailored (dynamic and static) mechanical and barrier properties, approaching those of poly(ethylene terephthalate), PET. The effect of reaction conditions on the properties of CNC-PLLA nanomaterials have been carefully studied and detailed throughout the paper. Copyright © 2016 Elsevier Ltd. All rights reserved.

Minimization of Surface Roughness and Tool Vibration in CNC Milling Operation

Directory of Open Access Journals (Sweden)

Sukhdev S. Bhogal

2015-01-01

Full Text Available Tool vibration and surface roughness are two important parameters which affect the quality of the component and tool life which indirectly affect the component cost. In this paper, the effect of cutting parameters on tool vibration, and surface roughness has been investigated during end milling of EN-31 tool steel. Response surface methodology (RSM has been used to develop mathematical model for predicting surface finish, tool vibration and tool wear with different combinations of cutting parameters. The experimental results show that feed rate is the most dominating parameter affecting surface finish, whereas cutting speed is the major factor effecting tool vibration. The results of mathematical model are in agreement with experimental investigations done to validate the mathematical model.

Physicochemical characterization of cellulose nanocrystal and nanoporous self-assembled CNC membrane derived from Ceiba pentandra.

Science.gov (United States)

Mohamed, Mohamad Azuwa; W Salleh, W N; Jaafar, Juhana; Ismail, A F; Abd Mutalib, Muhazri; Mohamad, Abu Bakar; M Zain, M F; Awang, Nor Asikin; Mohd Hir, Zul Adlan

2017-02-10

This research involves the rare utilisation of the kapok fibre (Ceiba pentandra) as a raw material for the fabrication of cellulose nanocrystal (CNC) and self-assembled CNC membranes. The isolation of CNC from Ceiba pentandra began with the extraction of cellulose via the chemical alkali extraction by using 5wt% NaOH, followed by the typical acidified bleaching method and, finally, the CNC production through acid hydrolysis with 60wt% H 2 SO 4 at the optimum time of 60min. The prepared CNC was then employed for the preparation of self-assembled membrane through the water suspension casting evaporation technique. The obtained CNC membrane was characterised in terms of its composition, crystallinity, thermal stability, as well as, structural and morphological features with the use of several techniques including FTIR, XRD, AFM, TEM, FESEM, and TGA. The FESEM and AFM analyses had illustrated the achievement of a self-assembled CNC membrane with a smooth surface and a well-distributed nano-porous structure, with the porosity of 52.82±7.79%. In addition, the findings proved that the self-assembled CNC membrane displayed good adsorption capability indicated by the recorded efficiency of 79% and 85% for 10mg/L and 5mg/L of methylene blue in an aqueous solution, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

Normative data for the Maryland CNC Test.

Science.gov (United States)

Mendel, Lisa Lucks; Mustain, William D; Magro, Jessica

2014-09-01

The Maryland consonant-vowel nucleus-consonant (CNC) Test is routinely used in Veterans Administration medical centers, yet there is a paucity of published normative data for this test. The purpose of this study was to provide information on the means and distribution of word-recognition scores on the Maryland CNC Test as a function of degree of hearing loss for a veteran population. A retrospective, descriptive design was conducted. The sample consisted of records from veterans who had Compensation and Pension (C&P) examinations at a Veterans Administration medical center (N = 1,760 ears). Audiometric records of veterans who had C&P examinations during a 10 yr period were reviewed, and the pure-tone averages (PTA4) at four frequencies (1000, 2000, 3000, and 4000 Hz) were documented. The maximum word-recognition score (PBmax) was determined from the performance-intensity functions obtained using the Maryland CNC Test. Correlations were made between PBmax and PTA4. A wide range of word-recognition scores were obtained at all levels of PTA4 for this population. In addition, a strong negative correlation between the PBmax and the PTA4 was observed, indicating that as PTA4 increased, PBmax decreased. Word-recognition scores decreased significantly as hearing loss increased beyond a mild hearing loss. Although threshold was influenced by age, no statistically significant relationship was found between word-recognition score and the age of the participants. RESULTS from this study provide normative data in table and figure format to assist audiologists in interpreting patient results on the Maryland CNC test for a veteran population. These results provide a quantitative method for audiologists to use to interpret word-recognition scores based on pure-tone hearing loss. American Academy of Audiology.

Preparation of CNC-dispersed Fe3O4 nanoparticles and their application in conductive paper.

Science.gov (United States)

Liu, Kai; Nasrallah, Joseph; Chen, Lihui; Huang, Liulian; Ni, Yonghao

2015-08-01

Well-dispersed Fe3O4 nanoparticles (NPs) were synthesized by a co-precipitation method in the presence of cellulose nano-crystals (CNC) as the template. The thus prepared Fe3O4 NPs were then used as a coating agent for the preparation of conductive paper. Fourier transform infrared spectroscopy (FTIR) results revealed that the Fe3O4 NPs were immobilized on the CNC through interactions between the hydroxyl groups of CNC and Fe3O4. Scanning transmission electron microscopy (STEM) images showed that the Fe3O4 NPs prepared in the presence of CNC can be dispersed in the CNC network, while the Fe3O4 NPs prepared in the absence of CNC tended to aggregate in aqueous solutions. The conductivity of the Fe3O4 NPs coated paper can reach to 0.0269 S/m at the coating amount of 14.75 g/m(2) Fe3O4/CNC nanocomposites. Therefore, the thus obtained coated paper can be potentially used as anti-static packaging material in the packaging field. Copyright © 2015 Elsevier Ltd. All rights reserved.

Laboratory setup for incremental forming at IPL

DEFF Research Database (Denmark)

Young, Dave; Andreasen, Jan Lasson

and machining laboratories. A laboratory equipment was developed during spring 2004 with our Cincinatti CNC milling machine as basis. The first obstacle to overcome was to establish a possibility for running CNC programs larger than capacity of the memory in the CNC controller of the milling machine. A solution...... is a collection of the work done by Dave in cooperation with Lars P. Holmbæck, Jan L. Andreasen and Niels Bay during his 1 month stay here. The work has been concentrated on following subjects: 1. Design and construction of a rig for SPIF for our Cincinatti CNC milling machine 2. Establishment of methods...

CNC Preparation Meets Manufacturing Opportunity

Science.gov (United States)

Cassola, Joel

2006-01-01

This article features the machining technology program at Cape Fear Community College (CFCC) of Wilmington, North Carolina. North Carolina's Cape Fear Community College is working to meet diverse industry needs through its CNC training. The school's program has gained the attention of the local manufacturing community and students when it shifted…

SRA Grant Writing Tutorial

Science.gov (United States)

This tutorial will help give your organization a broad but succinct analysis of what the SRA grant program is about. This self-paced tutorial is organized under two segments: Overview of Grant Program and Program Details.

An integrated model for part-operation allocation and investments in CNC technology

NARCIS (Netherlands)

Bokhorst, J.A.C.; Slomp, J.; Suresh, N.

2002-01-01

This study addresses the issue of investment appraisal of new technology, specifically computer numerical control (CNC) machine tools in conjunction with optimal allocation of parts and operations on CNC machines as the investments take place. Part-operation allocation is the allocation of parts and

Researches Regarding The Circular Interpolation Algorithms At CNC Laser Cutting Machines

Science.gov (United States)

Tîrnovean, Mircea Sorin

2015-09-01

This paper presents an integrated simulation approach for studying the circular interpolation regime of CNC laser cutting machines. The circular interpolation algorithm is studied, taking into consideration the numerical character of the system. A simulation diagram, which is able to generate the kinematic inputs for the feed drives of the CNC laser cutting machine is also presented.

Historical review of tutorial in education

Directory of Open Access Journals (Sweden)

María Gabriela Luna Pérez

2015-01-01

Full Text Available For centuries, tutorials have always been of an individual character in the history of education. The paper reviews how tutorials in education have evolved from ancient Greece to the present by considering taking into account the following aspects: a its general understanding, b the favorite areas of orientation c the role of learning guiding process d the supporting role of tutorials. We offer a historical account of tutorials development in Mexican Education. The study provides the main trends of tutorial activities in primary education, the evidence confirmed that tutoring has evolved from the learning of philosophical and ethical questions to the multiple learning involving competencies.

Designing CNC Knit for Hybrid Membrane And Bending Active Structures

DEFF Research Database (Denmark)

Tamke, Martin; Holden Deleuran, Anders; Gengnagel, Christoph

2015-01-01

specific properties and detailing. CNC knitting with high tenacity yarn enables this practice and offers an alternative to current woven membranes. The design and fabrication of an 8m high fabric tower through an interdisciplinary team of architects, structural and textile engineers, allowed to investigate...... means to design, specify, make and test CNC knit as material for hybrid structures in architectural scale. This paper shares the developed process, identifies challenges, potentials and future work...

A 5' online tutorial about 'how to prepare for a 5' online tutorial'

CERN Multimedia

CERN. Geneva

2016-01-01

This 4' video summarises our experience from short online tutorial recordings for the last 6 months. It contains important points for speakers' preparation and things to observe during the online tutorial recordings. For more details, check out our e-learning twiki.

Video Tutorial of Continental Food

Science.gov (United States)

Nurani, A. S.; Juwaedah, A.; Mahmudatussa'adah, A.

2018-02-01

This research is motivated by the belief in the importance of media in a learning process. Media as an intermediary serves to focus on the attention of learners. Selection of appropriate learning media is very influential on the success of the delivery of information itself both in terms of cognitive, affective and skills. Continental food is a course that studies food that comes from Europe and is very complex. To reduce verbalism and provide more real learning, then the tutorial media is needed. Media tutorials that are audio visual can provide a more concrete learning experience. The purpose of this research is to develop tutorial media in the form of video. The method used is the development method with the stages of analyzing the learning objectives, creating a story board, validating the story board, revising the story board and making video tutorial media. The results show that the making of storyboards should be very thorough, and detailed in accordance with the learning objectives to reduce errors in video capture so as to save time, cost and effort. In video capturing, lighting, shooting angles, and soundproofing make an excellent contribution to the quality of tutorial video produced. In shooting should focus more on tools, materials, and processing. Video tutorials should be interactive and two-way.

Conversion economics of forest biomaterials: risk and financial analysis of CNC manufacturing

Science.gov (United States)

Camilla Abbati de Assis; Carl Houtman; Richard Phillips; E.M. Ted Bilek; Orlando J. Rojas; Lokendra Pal; Maria Soledad Peresin; Hasan Jameel; Ronalds Gonzalez

2017-01-01

Commercialization of cellulose nanocrystals (CNC) presents opportunities for a wide range of new products. Techno-economic assessments can provide insightful information for the effi cient design of conversion processes, drive cost-saving efforts, and reduce fi nancial risks. In this study, we conducted techno-economic assessments for CNC production using information...

Generation of gear tooth surfaces by application of CNC machines

Science.gov (United States)

Litvin, F. L.; Chen, N. X.

1994-01-01

This study will demonstrate the importance of application of computer numerically controlled (CNC) machines in generation of gear tooth surfaces with new topology. This topology decreases gear vibration and will extend the gear capacity and service life. A preliminary investigation by a tooth contact analysis (TCA) program has shown that gear tooth surfaces in line contact (for instance, involute helical gears with parallel axes, worm gear drives with cylindrical worms, etc.) are very sensitive to angular errors of misalignment that cause edge contact and an unfavorable shape of transmission errors and vibration. The new topology of gear tooth surfaces is based on the localization of bearing contact, and the synthesis of a predesigned parabolic function of transmission errors that is able to absorb a piecewise linear function of transmission errors caused by gear misalignment. The report will describe the following topics: description of kinematics of CNC machines with six degrees of freedom that can be applied for generation of gear tooth surfaces with new topology. A new method for grinding of gear tooth surfaces by a cone surface or surface of revolution based on application of CNC machines is described. This method provides an optimal approximation of the ground surface to the given one. This method is especially beneficial when undeveloped ruled surfaces are to be ground. Execution of motions of the CNC machine is also described. The solution to this problem can be applied as well for the transfer of machine tool settings from a conventional generator to the CNC machine. The developed theory required the derivation of a modified equation of meshing based on application of the concept of space curves, space curves represented on surfaces, geodesic curvature, surface torsion, etc. Condensed information on these topics of differential geometry is provided as well.

CNC Turning Center Advanced Operations. Computer Numerical Control Operator/Programmer. 444-332.

Science.gov (United States)

Skowronski, Steven D.; Tatum, Kenneth

This student guide provides materials for a course designed to introduce the student to the operations and functions of a two-axis computer numerical control (CNC) turning center. The course consists of seven units. Unit 1 presents course expectations and syllabus, covers safety precautions, and describes the CNC turning center components, CNC…

Cutting Temperature Investigation of AISI H13 in High Speed End Milling

Directory of Open Access Journals (Sweden)

Muhammad Riza

2016-10-01

Full Text Available Heat produced at the tool-chip interface during high speed milling operations have been known as a significant factor that affect to tool life and workpiece geometry or properties. This paper aims to investigate cutting temperature behaviours of AISI H13 (48 HRC under high speed machining circumstances during pocketing. The experiments were conducted on CNC vertical machining centre by using PVD coated carbide insert. Milling processes were done at cutting speeds 150, 200 and 250 m/min and feed rate were 0.05, 0.1 and 0.15 mm/tooth. Depths of cut applied were 0.1, 0.15 and 0.2 mm. Tool path method applied in this experiment was contour in. Results presented in this paper indicate that by increasing cutting speed the cutting temperature is lower than low cutting speed. However, by decreasing feed rate leads to cutting temperature low. Cutting temperature phenomena at the corner of pocket milling were also investigated. The phenomena showed that cutting temperature tends to decrease a moment when cutter comes to the corner of pocket and turning point of tool path and increase extremely a moment before leaving the corner and turning point.

Servo-controlling structure of five-axis CNC system for real-time NURBS interpolating

Science.gov (United States)

Chen, Liangji; Guo, Guangsong; Li, Huiying

2017-07-01

NURBS (Non-Uniform Rational B-Spline) is widely used in CAD/CAM (Computer-Aided Design / Computer-Aided Manufacturing) to represent sculptured curves or surfaces. In this paper, we develop a 5-axis NURBS real-time interpolator and realize it in our developing CNC(Computer Numerical Control) system. At first, we use two NURBS curves to represent tool-tip and tool-axis path respectively. According to feedrate and Taylor series extension, servo-controlling signals of 5 axes are obtained for each interpolating cycle. Then, generation procedure of NC(Numerical Control) code with the presented method is introduced and the method how to integrate the interpolator into our developing CNC system is given. And also, the servo-controlling structure of the CNC system is introduced. Through the illustration, it has been indicated that the proposed method can enhance the machining accuracy and the spline interpolator is feasible for 5-axis CNC system.

Investigation of the effect of cutting speed on the Surface Roughness parameters in CNC End Milling using Artificial Neural Network

International Nuclear Information System (INIS)

Al Hazza, Muataz H F; Adesta, Erry Y T

2013-01-01

This research presents the effect of high cutting speed on the surface roughness in the end milling process by using the Artificial Neural Network (ANN). An experimental investigation was conducted to measure the surface roughness for end milling. A set of sparse experimental data for finish end milling on AISI H13 at hardness of 48 HRC have been conducted. The artificial neural network (ANN) was applied to simulate and study the effect of high cutting speed on the surface roughness

Learning from tutorials: a qualitative study of approaches to learning and perceptions of tutorial interaction

DEFF Research Database (Denmark)

Herrmann, Kim Jesper

2014-01-01

This study examines differences in university students’ approaches to learning when attending tutorials as well as variation in students’ perceptions of tutorials as an educational arena. In-depth qualitative analysis of semi-structured interviews with undergraduates showed how surface and deep...... approaches to learning were revealed in the students’ note-taking, listening, and engaging in dialogue. It was also shown how variation in the students’ approaches to learning were coherent with variation in the students’ perceptions of the tutors’ pedagogical role, the value of peer interaction......, and the overall purpose of tutorials. The results are discussed regarding the paradox that students relying on surface approaches to learning seemingly are the ones least likely to respond to tutorials in the way they were intended....

Investigation and Evaluation on Influence of Machining (CNC Conditions on Surface Quality of Paulownia Wood

Directory of Open Access Journals (Sweden)

Mohammad Aghajani

2012-01-01

Full Text Available The aim of this study was to investigate the effective factors on surface quality of paulownia wood during machining by advanced computer numerical controled (CNC machine. For this aim paulownia logs were provided and were converted to proper sizes (2.5 x 10 x 15 cm and then air dried. The Variable of this study were cutting speed (8.37 and 15.07 m/s, feeding rate (6 and 12 m/min, cutting depth (1and 5 mm, cutting method (down and up-milling and cutting pattern (tangential and radial. Roughness of cut specimens edge were evaluated by profilometer method according to ISO 13565 standard. For evaluation of surface quality, average roughness (Ra, maximum roughness (R max, valley roughness (Rv and peak roughness (Rp were used. Degrees of effectiveness of the parameters were evaluated by fractional factorial design as completely random design at confidence level of 95%. The result showed that cutting speed, cutting method and feed rate are influencive factors on surface quality of machined specimens and their effects were significant. With increasing cutting speed and decreasing feeding rate the roughness decreased and surface quality improved. In up-milling cutting method, degree of roughness was higher and consequently surface quality was inferior. It is to be noted that cutting method in comparison to other factors had the high influence on surface quality. The rest variables did now have independent influence on surface quality at 95% Confidence level. This study for achieving the optimum surface quality recommends that cutting speed of 15.07 m/s, feeding rate of 6 m/min, cutting method of down-milling and cutting depth of 1 mm for tangential cross section.

[CNC proteins in physiology and pathology].

Science.gov (United States)

Gęgotek, Agnieszka; Skrzydlewska, Elżbieta

2015-07-06

CNC proteins consist of Bach1, Bach2 and 4 homologous transcription factors: Nrf1, Nrf2, Nrf3 and p45NF-E2. Transcription factors belonging to this group of proteins play a crucial role in protection of cells against oxidative stress. Under physiological conditions, they remain in the cytoplasm in the inactive form or are degraded. However, in oxidative stress conditions, they are translocated to the nucleus, and bind to DNA in the ARE sequence. Consequently, there is transcription of genes encoding cytoprotective proteins, such as phase II enzymes, or low molecular weight antioxidant proteins (i.e., thioredoxin, ferritin, metallothionein) responsible for protecting cells from reactive oxygen species (ROS) action. The activity of transcriptional proteins depends directly on the redox state of the cell. ROS as second messenger signals, control inhibitors of cytoplasmic CNC proteins or potentiate the activity of kinases (MAPK, PKC, PI3K, PERK), leading to phosphorylation of transcription factors. This is conducive to translocation of these molecules into the nucleus and to formation of complexes that initiate the gene expression. Disorders of regulation of the activity of transcription factors belonging to the CNC proteins caused by gene mutations, epigenetic modifications or increased activity of p62, p21, or k-Ras, B-Raf and c-Myc oncogenes, induce changes in the level of ARE-dependent gene expression, which can lead even to the development of carcinogenesis. On the other hand, Nrf transcription factors, inducing the expression of antioxidants and enzymes responsible for the detoxification of xenobiotics, can be considered as a potential target of the action of chemopreventive factors in anticancer therapy.

CNC proteins in physiology and pathology

Directory of Open Access Journals (Sweden)

Agnieszka Gęgotek

2015-07-01

Full Text Available CNC proteins consist of Bach1, Bach2 and 4 homologous transcription factors: Nrf1, Nrf2, Nrf3 and p45NF-E2. Transcription factors belonging to this group of proteins play a crucial role in protection of cells against oxidative stress. Under physiological conditions, they remain in the cytoplasm in the inactive form or are degraded. However, in oxidative stress conditions, they are translocated to the nucleus, and bind to DNA in the ARE sequence. Consequently, there is transcription of genes encoding cytoprotective proteins, such as phase II enzymes, or low molecular weight antioxidant proteins (i.e., thioredoxin, ferritin, metallothionein responsible for protecting cells from reactive oxygen species (ROS action. The activity of transcriptional proteins depends directly on the redox state of the cell. ROS as second messenger signals, control inhibitors of cytoplasmic CNC proteins or potentiate the activity of kinases (MAPK, PKC, PI3K, PERK, leading to phosphorylation of transcription factors. This is conducive to translocation of these molecules into the nucleus and to formation of complexes that initiate the gene expression. Disorders of regulation of the activity of transcription factors belonging to the CNC proteins caused by gene mutations, epigenetic modifications or increased activity of p62, p21, or k-Ras, B-Raf and c-Myc oncogenes, induce changes in the level of ARE-dependent gene expression, which can lead even to the development of carcinogenesis. On the other hand, Nrf transcription factors, inducing the expression of antioxidants and enzymes responsible for the detoxification of xenobiotics, can be considered as a potential target of the action of chemopreventive factors in anticancer therapy.

Preliminary Development of Real Time Usage-Phase Monitoring System for CNC Machine Tools with a Case Study on CNC Machine VMC 250

Science.gov (United States)

Budi Harja, Herman; Prakosa, Tri; Raharno, Sri; Yuwana Martawirya, Yatna; Nurhadi, Indra; Setyo Nogroho, Alamsyah

2018-03-01

The production characteristic of job-shop industry at which products have wide variety but small amounts causes every machine tool will be shared to conduct production process with dynamic load. Its dynamic condition operation directly affects machine tools component reliability. Hence, determination of maintenance schedule for every component should be calculated based on actual usage of machine tools component. This paper describes study on development of monitoring system to obtaining information about each CNC machine tool component usage in real time approached by component grouping based on its operation phase. A special device has been developed for monitoring machine tool component usage by utilizing usage phase activity data taken from certain electronics components within CNC machine. The components are adaptor, servo driver and spindle driver, as well as some additional components such as microcontroller and relays. The obtained data are utilized for detecting machine utilization phases such as power on state, machine ready state or spindle running state. Experimental result have shown that the developed CNC machine tool monitoring system is capable of obtaining phase information of machine tool usage as well as its duration and displays the information at the user interface application.

CNC TORNA TEZGAHLARINDA KESME KUVVETLERİ ANALİZİ - DENEYSEL YAKLAŞIM

Directory of Open Access Journals (Sweden)

Erdem Koç

1996-01-01

Full Text Available Bu çalışma, CNC torna tezgahlarında programlama yapmanın kolaylaştırılmasını, hazırlanan parça programının tezgaha ait sınır parametrelerine göre optimizasyonunu sağlamaktadır. Çalışmada deney ve optimizasyon işlemlerinde BOXFORD 250 B CNC torna tezgahı kullanılmıştır. CNC torna tezgahında kaleme gelen kuvvetlerin ölçülmesi gerçekleştirilmiştir. Yapılan deneylerde yüzey tornalama işleminde kesici uçları için oluşan kesme kuvvetleri; değişik talaş derinlikleri, ilerleme ve kesme hızları ile kesici uçları için tespit edilerek bir veri tabanı elde edilmiştir.

Additively Manufactured Titanium and Cobalt-Chromium Implant Frameworks: Fit and Effect of Ceramic Veneering.

Science.gov (United States)

Svanborg, Per; Eliasson, Alf; Stenport, Victoria

The purpose of this study was to evaluate the fit of additively manufactured cobalt-chromium and titanium and CNC-milled titanium frameworks before and after ceramic veneering. Ten stone casts simulating an edentulous maxilla provided with six abutment analogs were produced. For each stone cast, one additively manufactured cobalt-chromium framework (AM CoCr) and one titanium framework (AM Ti) were fabricated. The fit was analyzed with a coordinate measuring machine in three dimensions (x, y, and z axes) using best-fit virtual matching of center point coordinates, before and after ceramic veneering. CNC-milled titanium frameworks (CNC Ti) and earlier results from CNC-milled cobalt-chromium frameworks (CNC CoCr) were used for comparison. All frameworks presented minor misfit before and after veneering in the horizontal plane (x- and y-axes) between 2.9 and 13.5 μm and in the vertical plane (z-axis) between 1.6 and 5.4 μm. Ceramic veneering affected the fit of all groups of frameworks. Both AM Ti and AM CoCr presented significantly smaller distortion in the vertical plane compared with the CNC-milled frameworks. Implant-supported frameworks can be produced in either Ti or CoCr using either CNC milling or additive manufacturing with a fit well within the range of 20 μm in the horizontal plane and 10 μm in the vertical plane. The fit of frameworks of both materials and production techniques are affected by the ceramic veneering procedure to a small extent.

The "magic" of tutorial centres in Hong Kong: An analysis of media marketing and pedagogy in a tutorial centre

Science.gov (United States)

Koh, Aaron

2014-12-01

Why do more than three-quarters of Hong Kong's senior secondary students flock to tutorial centres like moths to light? What is the "magic" that is driving the popularity of the tutorial centre enterprise? Indeed, looking at the ongoing boom of tutorial centres in Hong Kong (there are almost 1,000 of them), it is difficult not to ask these questions. This paper examines the phenomenon of tutorial centres in Hong Kong and seeks to understand what draws students to these centres. Combining theories of marketing semiotics and emotion studies, the author investigates the pivotal role of media marketing in generating the "magic" of tutorial centres, whose advertising strategy includes, for example, a display of billboard posters featuring stylishly-dressed "celebrity teachers". The author reviews some of the literature available on the subject of tutorial centres. In a case study approach, he then maps out the pedagogy he observed in an English tutorial class, seeking heuristic insights into the kind of teaching students in the study were looking for. He argues that part of the "magical" attraction of what are essentially "cram schools" is their formulaic pedagogy of teaching and reinforcing exam skills. Finally, the paper considers the social implications of the tutorial centre industry in terms of media marketing of education and unequal access to tutorial services.

Cellulose nanocrystals (CNC) as carriers for a spirooxazine dye and its effect on photochromic efficiency.

Science.gov (United States)

Sun, Bo; Hou, Qingxi; He, Zhibin; Liu, Zehua; Ni, Yonghao

2014-10-13

Nanocrystalline cellulose (CNC) as a renewable/sustainable material, has received much attention. Herein we studied CNC as carriers for a hydrophobic spirooxazine (SO)-based dye, 1,3-dihydro-1,3,3-trimethylspiro[2H-indole-2,3'-[3H]naphtha[2,1-b][1,4]oxazine], which may have potential applications in reversible memory photo-devices, textiles, photo-sensitive paper coatings, and inkjet printing inks. Due to the high cost and water-insolubility of this dye, it is desirable to improve its coloration efficiency and water-dispersibility. The experimental approach was to use CNC as carriers for the SO dye, thus obtaining a stable photochromic dye in aqueous systems. Transmission electron microscope (TEM) observation confirmed that the SO dye adsorbed on the surface of the CNC, which functioned as carriers for the photochromic dye. An impregnation process was adopted to anchor the dye onto cellulosic paper. It was found that the use of CNC resulted in a significant improvement in the SO coloration efficiency. The color stability and fatigue resistance were also studied. The use of CNC as carriers for a hydrophobic compound, its enhancement of associated properties, and its subsequent application were demonstrated. Copyright © 2014 Elsevier Ltd. All rights reserved.

Renner-Teller effects in the photoelectron spectra of CNC, CCN, and HCCN.

Science.gov (United States)

Coudert, Laurent H; Gans, Bérenger; Garcia, Gustavo A; Loison, Jean-Christophe

2018-02-07

The line intensity of photoelectron spectra when either the neutral or cationic species display a Renner-Teller coupling is derived and applied to the modeling of the photoelectron spectra of CNC, CCN, and HCCN. The rovibronic energy levels of these three radicals and of their cations are investigated starting from ab initio results. A model treating simultaneously the bending mode and the overall rotation is developed to deal with the quasilinearity problem in CNC + , CCN + , and HCCN and accounts for the large amplitude nature of their bending mode. This model is extended to treat the Renner-Teller coupling in CNC, CCN, and HCCN + . Based on the derived photoelectron line intensity, the photoelectron spectra of all three molecules are calculated and compared to the experimental ones.

Fuzzy Linguistic Optimization on Surface Roughness for CNC Turning

Directory of Open Access Journals (Sweden)

Tian-Syung Lan

2010-01-01

Full Text Available Surface roughness is often considered the main purpose in contemporary computer numerical controlled (CNC machining industry. Most existing optimization researches for CNC finish turning were either accomplished within certain manufacturing circumstances or achieved through numerous equipment operations. Therefore, a general deduction optimization scheme is deemed to be necessary for the industry. In this paper, the cutting depth, feed rate, speed, and tool nose runoff with low, medium, and high level are considered to optimize the surface roughness for finish turning based on L9(34 orthogonal array. Additionally, nine fuzzy control rules using triangle membership function with respective to five linguistic grades for surface roughness are constructed. Considering four input and twenty output intervals, the defuzzification using center of gravity is then completed. Thus, the optimum general fuzzy linguistic parameters can then be received. The confirmation experiment result showed that the surface roughness from the fuzzy linguistic optimization parameters is significantly advanced compared to that from the benchmark. This paper certainly proposes a general optimization scheme using orthogonal array fuzzy linguistic approach to the surface roughness for CNC turning with profound insight.

Development of a QFD-based expert system for CNC turning centre selection

Science.gov (United States)

Prasad, Kanika; Chakraborty, Shankar

2015-12-01

Computer numerical control (CNC) machine tools are automated devices capable of generating complicated and intricate product shapes in shorter time. Selection of the best CNC machine tool is a critical, complex and time-consuming task due to availability of a wide range of alternatives and conflicting nature of several evaluation criteria. Although, the past researchers had attempted to select the appropriate machining centres using different knowledge-based systems, mathematical models and multi-criteria decision-making methods, none of those approaches has given due importance to the voice of customers. The aforesaid limitation can be overcome using quality function deployment (QFD) technique, which is a systematic approach for integrating customers' needs and designing the product to meet those needs first time and every time. In this paper, the adopted QFD-based methodology helps in selecting CNC turning centres for a manufacturing organization, providing due importance to the voice of customers to meet their requirements. An expert system based on QFD technique is developed in Visual BASIC 6.0 to automate the CNC turning centre selection procedure for different production plans. Three illustrative examples are demonstrated to explain the real-time applicability of the developed expert system.

PLLA-grafted cellulose nanocrystals: Role of the CNC content and grafting on the PLA bionanocomposite film properties.

Science.gov (United States)

Lizundia, Erlantz; Fortunati, Elena; Dominici, Franco; Vilas, José Luis; León, Luis Manuel; Armentano, Ilaria; Torre, Luigi; Kenny, Josè M

2016-05-20

Cellulose nanocrystals (CNC), extracted from microcrystalline cellulose by acid hydrolysis, were grafted by ring opening polymerization of L-Lactide initiated from the hydroxyl groups available at their surface and two different CNC:L-lactide ratios (20:80 and 5:95) were obtained. The resulting CNC-g-PLLA nanohybrids were incorporated in poly(lactic acid) (PLA) matrix by an optimized extrusion process at two different content (1 wt.% and 3 wt.%) and obtained bionanocomposite films were characterized by thermal, mechanical, optical and morphological properties. Thermal analysis showed CNC grafted with the higher ratio of lactide play a significant role as a nucleating agent. Moreover, they contribute to a significant increase in the crystallization rate of PLA, and the best efficiency was revealed with 3 wt.% of CNC-g-PLLA. This effect was confirmed by the increased in Young's modulus, suggesting the CNC graft ratio and content contribute significantly to the good dispersion in the matrix, positively affecting the final bionanocomposite properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

TMVA tutorial

CERN Multimedia

CERN. Geneva; VOSS, Helge

2015-01-01

This tutorial will both give an introduction on how to use TMVA in root6 and showcase some new features, such as modularity, variable importance, interfaces to R and python. After explaining the basic functionality, the typical steps required during a real life application (such as variable selection, pre-processing, tuning and classifier evaluation) will be demonstrated on simple examples. First part of the tutorial will use the usual Root interface (please make sure you have Root 6.04 installed somewhere). The second part will utilize the new server notebook functionality of Root as a Service. If you are within CERN but outside the venue or outside CERN please consult the notes attached.

Chemical crosslinking of acrylic acid to form biocompatible pH sensitive hydrogel reinforced with cellulose nanocrystals (CNC)

International Nuclear Information System (INIS)

Lim, Lim Sze; Ahmad, Ishak; Lazim, Mohd Azwani Shah Mat; Amin, Mohd. Cairul Iqbal Mohd

2014-01-01

The purpose of this study is to produce a novel pH and temperature sensitive hydrogel, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. The PAA was then subjected to chemical cross-linking using the cross-linking agent (N,N-methylenebisacrylamide) with CNC entrapped in PAA matrix. The mixture was casted onto petri dish to obtain disc shape hydrogel. The effects of reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH and temperature were studied. The obtained hydrogel was further subjected to different tests such swelling test for swelling behaviour at different pH and temperature along with scanning electron microscopy (SEM) for morphology analysis. The hydrogel obtained showed excellent pH sensitivity and obtained maximum swelling at pH 7. Besides that, hydrogel obtained showed significant increase in swelling ratio when temperature of swelling medium was increased from 25°C to 37°C. SEM micrograph showed that the pore size of the hydrogel decreases with increase of CNC content proving that the hydrogel structure became more rigid with addition of CNC. The PAA/CNC hydrogel with such excellent sensitivity towards pH and temperature can be developed further as drug carrier

Chemical crosslinking of acrylic acid to form biocompatible pH sensitive hydrogel reinforced with cellulose nanocrystals (CNC)

Energy Technology Data Exchange (ETDEWEB)

Lim, Lim Sze; Ahmad, Ishak; Lazim, Mohd Azwani Shah Mat [Faculty of Science and Technology, University Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor (Malaysia); Amin, Mohd. Cairul Iqbal Mohd [Faculty of Pharmacy, University Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur (Malaysia)

2014-09-03

The purpose of this study is to produce a novel pH and temperature sensitive hydrogel, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. The PAA was then subjected to chemical cross-linking using the cross-linking agent (N,N-methylenebisacrylamide) with CNC entrapped in PAA matrix. The mixture was casted onto petri dish to obtain disc shape hydrogel. The effects of reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH and temperature were studied. The obtained hydrogel was further subjected to different tests such swelling test for swelling behaviour at different pH and temperature along with scanning electron microscopy (SEM) for morphology analysis. The hydrogel obtained showed excellent pH sensitivity and obtained maximum swelling at pH 7. Besides that, hydrogel obtained showed significant increase in swelling ratio when temperature of swelling medium was increased from 25°C to 37°C. SEM micrograph showed that the pore size of the hydrogel decreases with increase of CNC content proving that the hydrogel structure became more rigid with addition of CNC. The PAA/CNC hydrogel with such excellent sensitivity towards pH and temperature can be developed further as drug carrier.

Onderzoeksresultaten introductie CNC bij een zestal bedrijven

NARCIS (Netherlands)

Mal, van H.H.; Ottink, M.S.; Peters, R.B.

1987-01-01

In het kader van een afstudeerproject van de faculteit bedrijfskunde aan de Technische Universiteit Eindhoven is er een onderzoek gedaan naar het gebruik en de gevolgen van het gebruikvan CNC-bewerkings machines in industriële organisaties [1]. Het onderzoek werd uitgevoerd in een zestal bedrijven,

The BTeV Software Tutorial Suite

International Nuclear Information System (INIS)

Kutschke, Robert K.

2004-01-01

The BTeV Collaboration is starting to develop its C++ based offline software suite, an integral part of which is a series of tutorials. These tutorials are targeted at a diverse audience, including new graduate students, experienced physicists with little or no C++ experience, those with just enough C++ to be dangerous, and experts who need only an overview of the available tools. The tutorials must both teach C++ in general and the BTeV specific tools in particular. Finally, they must teach physicists how to find and use the detailed documentation. This report will review the status of the BTeV experiment, give an overview of the plans for and the state of the software and will then describe the plans for the tutorial suite

OAI-PMH basics Tutorial 3

CERN Document Server

CERN. Geneva

2007-01-01

This tutorial is aimed at those who are new to the area of repositories and who want to learn more about key advocacy and policy issues. The tutorial will include information and advice on putting together an institutional advocacy campaign and developing policies for your repository. There will be opportunities for participants to share experiences and to ask questions. The tutorial will include a practical exercise in developing an advocacy presentation. Participants with experience of advocacy are welcome to attend the session to share their experiences, but should bear in mind that it is aimed primarily at those looking for help and advice in advocacy matters.

Karibu Tutorials

DEFF Research Database (Denmark)

Christensen, Henrik Bærbak

These tutorials demonstrate how to use Karibu for high quality data collection, in particular how to setup a distributed Karibu system and how to adapt Karibu to your particular data collection needs....

High productivity mould robotic milling in Al-5083

Science.gov (United States)

Urresti, Iker; Arrazola, Pedro Jose; Ørskov, Klaus Bonde; Pelegay, Jose Angel

2018-05-01

Industrial serial robots were usually limited to welding, handling or spray painting operations until very recent years. However, some industries have already realized about their important capabilities in terms of flexibility, working space, adaptability and cost. Hence, currently they are seriously being considered to carry out certain metal machining tasks. Therefore, robot based machining is presented as a cost-saving and flexible manufacturing alternative compared to conventional CNC machines especially for roughing or even pre-roughing of large parts. Nevertheless, there are still some drawbacks usually referred as low rigidity, accuracy and repeatability. Thus, the process productivity is usually sacrificed getting low Material Removal Rates (MRR), and consequently not being competitive. Nevertheless, in this paper different techniques to obtain increased productivity are presented, though an appropriate selection of cutting strategies and parameters that are essential for it. During this research some rough milling tests in Al-5083 are presented where High Feed Milling (HFM) is implemented as productive cutting strategy and the experimental modal analysis named Tap-testing is used for the suitable choice of cutting conditions. Competitive productivity rates are experienced while process stability is checked through the cutting forces measurements in order to prove the effectiveness of the experimental modal analysis for robotic machining.

Integration and diversity of the regulatory network composed of Maf and CNC families of transcription factors.

Science.gov (United States)

Motohashi, Hozumi; O'Connor, Tania; Katsuoka, Fumiki; Engel, James Douglas; Yamamoto, Masayuki

2002-07-10

Recent progress in the analysis of transcriptional regulation has revealed the presence of an exquisite functional network comprising the Maf and Cap 'n' collar (CNC) families of regulatory proteins, many of which have been isolated. Among Maf factors, large Maf proteins are important in the regulation of embryonic development and cell differentiation, whereas small Maf proteins serve as obligatory heterodimeric partner molecules for members of the CNC family. Both Maf homodimers and CNC-small Maf heterodimers bind to the Maf recognition element (MARE). Since the MARE contains a consensus TRE sequence recognized by AP-1, Jun and Fos family members may act to compete or interfere with the function of CNC-small Maf heterodimers. Overall then, the quantitative balance of transcription factors interacting with the MARE determines its transcriptional activity. Many putative MARE-dependent target genes such as those induced by antioxidants and oxidative stress are under concerted regulation by the CNC family member Nrf2, as clearly proven by mouse germline mutagenesis. Since these genes represent a vital aspect of the cellular defense mechanism against oxidative stress, Nrf2-null mutant mice are highly sensitive to xenobiotic and oxidative insults. Deciphering the molecular basis of the regulatory network composed of Maf and CNC families of transcription factors will undoubtedly lead to a new paradigm for the cooperative function of transcription factors.

Teaching Game Programming using Video Tutorials

DEFF Research Database (Denmark)

Majgaard, Gunver

. & Squire K. (2004). Design-Based Research: Putting a Stake in the Ground. Journal of Learning Sciences Vol. 13-1. Lave, J., & Wenger, E. (1991). Situated Learning: Legitimate Peripheral Participation, Cambridge: Cambridge Univ. Majgaard, G. (2014). Teaching Design of Emerging Embodied Technologies......Background. What are the learning potentials of using online video tutorials as educational tools in game programming of Mixed Reality? The paper reports on the first experiences of teaching third semester engineering students design of Mixed Reality using online step-by-step programming video...... production makes video tutorials a promising alternative to paper tutorials. Software and game engine companies such as Unity has already switched to video and other online materials as the primary medium for their tutorials. It is often hard to find up to date thoroughly worked through textbooks on new...

Basic leucine zipper protein Cnc-C is a substrate and transcriptional regulator of the Drosophila 26S proteasome.

Science.gov (United States)

Grimberg, Kristian Björk; Beskow, Anne; Lundin, Daniel; Davis, Monica M; Young, Patrick

2011-02-01

While the 26S proteasome is a key proteolytic complex, little is known about how proteasome levels are maintained in higher eukaryotic cells. Here we describe an RNA interference (RNAi) screen of Drosophila melanogaster that was used to identify transcription factors that may play a role in maintaining levels of the 26S proteasome. We used an RNAi library against 993 Drosophila transcription factor genes to identify genes whose suppression in Schneider 2 cells stabilized a ubiquitin-green fluorescent protein reporter protein. This screen identified Cnc (cap 'n' collar [CNC]; basic region leucine zipper) as a candidate transcriptional regulator of proteasome component expression. In fact, 20S proteasome activity was reduced in cells depleted of cnc. Immunoblot assays against proteasome components revealed a general decline in both 19S regulatory complex and 20S proteasome subunits after RNAi depletion of this transcription factor. Transcript-specific silencing revealed that the longest of the seven transcripts for the cnc gene, cnc-C, was needed for proteasome and p97 ATPase production. Quantitative reverse transcription-PCR confirmed the role of Cnc-C in activation of transcription of genes encoding proteasome components. Expression of a V5-His-tagged form of Cnc-C revealed that the transcription factor is itself a proteasome substrate that is stabilized when the proteasome is inhibited. We propose that this single cnc gene in Drosophila resembles the ancestral gene family of mammalian nuclear factor erythroid-derived 2-related transcription factors, which are essential in regulating oxidative stress and proteolysis.

Tailoring the yield and characteristics of wood cellulose nanocrystals (CNC) using concentrated acid hydrolysis

Science.gov (United States)

Liheng Chen; Qianqian Wang; Kolby Hirth; Carlos Baez; Umesh P. Agarwal; J. Y. Zhu

2015-01-01

Cellulose nanocrystals (CNC) have recently received much attention in the global scientific community for their unique mechanical and optical properties. Here, we conducted the first detailed exploration of the basic properties of CNC, such as morphology, crystallinity, degree of sulfation and yield, as a function of production condition variables. The rapid cellulose...

Evaluation of internal fit of interim crown fabricated with CAD/CAM milling and 3D printing system.

Science.gov (United States)

Lee, Wan-Sun; Lee, Du-Hyeong; Lee, Kyu-Bok

2017-08-01

This study is to evaluate the internal fit of the crown manufactured by CAD/CAM milling method and 3D printing method. The master model was fabricated with stainless steel by using CNC machine and the work model was created from the vinyl-polysiloxane impression. After scanning the working model, the design software is used to design the crown. The saved STL file is used on the CAD/CAM milling method and two types of 3D printing method to produce 10 interim crowns per group. Internal discrepancy measurement uses the silicon replica method and the measured data are analyzed with One-way ANOVA to verify the statistic significance. The discrepancy means (standard deviation) of the 3 groups are 171.6 (97.4) µm for the crown manufactured by the milling system and 149.1 (65.9) and 91.1 (36.4) µm, respectively, for the crowns manufactured with the two types of 3D printing system. There was a statistically significant difference and the 3D printing system group showed more outstanding value than the milling system group. The marginal and internal fit of the interim restoration has more outstanding 3D printing method than the CAD/CAM milling method. Therefore, the 3D printing method is considered as applicable for not only the interim restoration production, but also in the dental prosthesis production with a higher level of completion.

ADAM13 cleavage of cadherin-11 promotes CNC migration independently of the homophilic binding site.

Science.gov (United States)

Abbruzzese, Genevieve; Becker, Sarah F; Kashef, Jubin; Alfandari, Dominique

2016-07-15

The cranial neural crest (CNC) is a highly motile population of cells that is responsible for forming the face and jaw in all vertebrates and perturbing their migration can lead to craniofacial birth defects. Cell motility requires a dynamic modification of cell-cell and cell-matrix adhesion. In the CNC, cleavage of the cell adhesion molecule cadherin-11 by ADAM13 is essential for cell migration. This cleavage generates a shed extracellular fragment of cadherin-11 (EC1-3) that possesses pro-migratory activity via an unknown mechanism. Cadherin-11 plays an important role in modulating contact inhibition of locomotion (CIL) in the CNC to regulate directional cell migration. Here, we show that while the integral cadherin-11 requires the homophilic binding site to promote CNC migration in vivo, the EC1-3 fragment does not. In addition, we show that increased ADAM13 activity or expression of the EC1-3 fragment increases CNC invasiveness in vitro and blocks the repulsive CIL response in colliding cells. This activity requires the presence of an intact homophilic binding site on the EC1-3 suggesting that the cleavage fragment may function as a competitive inhibitor of cadherin-11 adhesion in CIL but not to promote cell migration in vivo. Copyright © 2015. Published by Elsevier Inc.

Quantitative Microbial Risk Assessment Tutorial - Primer

Science.gov (United States)

This document provides a Quantitative Microbial Risk Assessment (QMRA) primer that organizes QMRA tutorials. The tutorials describe functionality of a QMRA infrastructure, guide the user through software use and assessment options, provide step-by-step instructions for implementi...

Frequent phosphodiesterase 11A gene (PDE11A) defects in patients with Carney complex (CNC) caused by PRKAR1A mutations: PDE11A may contribute to adrenal and testicular tumors in CNC as a modifier of the phenotype.

Science.gov (United States)

Libé, Rossella; Horvath, Anelia; Vezzosi, Delphine; Fratticci, Amato; Coste, Joel; Perlemoine, Karine; Ragazzon, Bruno; Guillaud-Bataille, Marine; Groussin, Lionel; Clauser, Eric; Raffin-Sanson, Marie-Laure; Siegel, Jennifer; Moran, Jason; Drori-Herishanu, Limor; Faucz, Fabio Rueda; Lodish, Maya; Nesterova, Maria; Bertagna, Xavier; Bertherat, Jerome; Stratakis, Constantine A

2011-01-01

Carney complex (CNC) is an autosomal dominant multiple neoplasia, caused mostly by inactivating mutations of the regulatory subunit 1A of the protein kinase A (PRKAR1A). Primary pigmented nodular adrenocortical disease (PPNAD) is the most frequent endocrine manifestation of CNC with a great inter-individual variability. Germline, protein-truncating mutations of phosphodiesterase type 11A (PDE11A) have been described to predispose to a variety of endocrine tumors, including adrenal and testicular tumors. Our objective was to investigate the role of PDE11A as a possible gene modifier of the phenotype in a series of 150 patients with CNC. A higher frequency of PDE11A variants in patients with CNC compared with healthy controls was found (25.3 vs. 6.8%, P CNC patients, those with PPNAD were significantly more frequently carriers of PDE11A variants compared with patients without PPNAD (30.8 vs. 13%, P = 0.025). Furthermore, men with PPNAD were significantly more frequently carriers of PDE11A sequence variants (40.7%) than women with PPNAD (27.3%) (P CNC patients, a high frequency of PDE11A variants, suggesting that PDE11A is a genetic modifying factor for the development of testicular and adrenal tumors in patients with germline PRKAR1A mutation.

A comparative study of using spindle motor power and eddy current for the detection of tool conditions in milling processes

OpenAIRE

Abbass, JK; Al-Habaibeh, A

2015-01-01

This paper investigates the use of the power of the driving motor of a CNC spindle in comparison to two perpendicular eddy current sensors for the detection of tool wear in milling processes. Monitoring the power through the current profile is a low cost system which has been utilised in this study as an attempt to detect the fluctuation in the motor load as a result of the conditions of the cutting tool. Eddy current sensors are dedicated sensors that are installed on the spindle to measure ...

Indico MEETING tutorial

CERN Multimedia

CERN. Geneva; Manzoni, Alex Marc; Dimou, Maria

2017-01-01

This short tutorial explains how to create a MEETING in indico, how to populate the timetable, write minutes and how to add material. If you are only interested in the timetable part, please slide to 03.39, for the minutes to 07.46 and for adding material to 08.29.   Tell us what you think via e-learning.support at cern.ch More tutorials in the e-learning collection of the CERN Document Server (CDS) http://cds.cern.ch/collection/E-learning%20modules?ln=en All info about the CERN rapid e-learning project is linked from http://twiki.cern.ch/ELearning  

Investigation of influence of errors of cutting machines with CNC on displacement trajectory accuracy of their actuating devices

Science.gov (United States)

Fedonin, O. N.; Petreshin, D. I.; Ageenko, A. V.

2018-03-01

In the article, the issue of increasing a CNC lathe accuracy by compensating for the static and dynamic errors of the machine is investigated. An algorithm and a diagnostic system for a CNC machine tool are considered, which allows determining the errors of the machine for their compensation. The results of experimental studies on diagnosing and improving the accuracy of a CNC lathe are presented.

Tutorials in university students with a disability

Directory of Open Access Journals (Sweden)

Joaquín Gairín Sallán

2013-10-01

Full Text Available This article places an emphasis on the importance of tutorials for students with a disability in universities. It presented the most significant results of the study of tutorials carried out in help services, units or offices for students with a disability inmore than 45 Spanish universities, in relation to promotion, reception, completion and graduation. The contributions highlight the importance of organising a response through a Tutorial Action Plan made up of the stages of motivation and awareness-raisin, planning, execution, evaluation and institutionalisation. Among the principle conclusions, the importance of moving towards a truly inclusive university through tutorial activity is highlighted, thereby providing a guide for providing assistance to university students with a disability.

Progress Report--Microsoft Office 2003 Lynchburg College Tutorials

Science.gov (United States)

Murray, Tom

2004-01-01

For the past several years Lynchburg College has developed Microsoft tutorials for use with academic classes and faculty, student and staff training. The tutorials are now used internationally. Last year Microsoft and Verizon sponsored a tutorial web site at http://www.officetutorials.com. This website recognizes ASCUE members for their wonderful…

Tutorial Instruction in Science Education

Directory of Open Access Journals (Sweden)

Rhea Miles

2015-06-01

Full Text Available The purpose of the study is to examine the tutorial practices of in-service teachers to address the underachievement in the science education of K-12 students. Method: In-service teachers in Virginia and North Carolina were given a survey questionnaire to examine how they tutored students who were in need of additional instruction. Results: When these teachers were asked, “How do you describe a typical one-on-one science tutorial session?” the majority of their responses were categorized as teacher-directed. Many of the teachers would provide a science tutorial session for a student after school for 16-30 minutes, one to three times a week. Respondents also indicated they would rely on technology, peer tutoring, scientific inquiry, or themselves for one-on-one science instruction. Over half of the in-service teachers that responded to the questionnaire stated that they would never rely on outside assistance, such as a family member or an after school program to provide tutorial services in science. Additionally, very few reported that they incorporated the ethnicity, culture, or the native language of ELL students into their science tutoring sessions.

Tutorials in university students with a disability

OpenAIRE

Joaquín Gairín Sallán; José Luís Muñoz Moreno

2013-01-01

This article places an emphasis on the importance of tutorials for students with a disability in universities. It presented the most significant results of the study of tutorials carried out in help services, units or offices for students with a disability inmore than 45 Spanish universities, in relation to promotion, reception, completion and graduation. The contributions highlight the importance of organising a response through a Tutorial Action Plan made up of the stages of motivation and ...

NVidia Tutorial

CERN Document Server

CERN. Geneva; MESSMER, Peter; DEMOUTH, Julien

2015-01-01

This tutorial will present Caffee, a powerful Python library to implement solutions working on CPUs and GPUs, and explain how to use it to build and train Convolutional Neural Networks using NVIDIA GPUs. The session requires no prior experience with GPUs or Caffee.

Advocacy and policy issues Tutorial 2

CERN Document Server

CERN. Geneva

2007-01-01

This tutorial is aimed at those who are new to the area of repositories and who want to learn more about key advocacy and policy issues. The tutorial will include information and advice on putting together an institutional advocacy campaign and developing policies for your repository. There will be opportunities for participants to share experiences and to ask questions. The tutorial will include a practical exercise in developing an advocacy presentation. Participants with experience of advocacy are welcome to attend the session to share their experiences, but should bear in mind that it is aimed primarily at those looking for help and advice in advocacy matters.

Solidaridad en la relación tutorial

Directory of Open Access Journals (Sweden)

Arturo G Rillo

Full Text Available Introducción. La tutoría académica concreta el proceso educativo sustentado en estándares de calidad, características y necesidades de aprendizaje del estudiante; se desenvuelve confrontando actividades pedagógicas y consolida solidaridades. En este contexto, el estudio se realizó con el propósito de realizar la analítica de la solidaridad que surge de la relación tutorial. Método. Desde el ámbito de la hermenéutica, se realizó un estudio en cuatro fases: analítica, comprensiva, reconstructiva, crítica. Se construyó el concepto de solidaridad en la relación tutorial con propuestas de Gadamer, Habermas, Adela Cortina y Edgar Morín. Las categorías de análisis fueron: construcción social del sentido en la relación tutorial, relación tutorial de naturaleza epistémica, compleja, infinita y cambiante; y práctica tutorial generadora de solidaridades. Resultados. La solidaridad como praxis humana orientada al cuidado del otro (Fürsorge promueve el encuentro con el estudiante. La tutoría académica regula la experiencia vital de la dualidad enseñar-aprender; articula la decisión del docente y alumno con la responsabilidad solidaria. El docente concreta un asentimiento aconsejado por la amistad de estar-ahí-con el estudiante, acompañándolo, posibilitando elecciones y decisiones entre posibilidades para una vida sustentable mediante la virtud de la phrónesis. Conclusiones. La solidaridad en la relación tutorial como horizonte de sentido engarza la cosmovisión del binomio docente-estudiante en la relación tutorial. Dado el vínculo social, se ubica en el escenario de la relación tutorial el sentido originario de la amistad y la solidaridad con los siguientes baremos: compasión, saber hacer, confidencialidad, confianza, conciencia de sí mismo y del otro, tacto, escucha atenta y solícita, comprensión del otro.

First year clinical tutorials: students’ learning experience

Directory of Open Access Journals (Sweden)

Burgess A

2014-11-01

Full Text Available Annette Burgess,1 Kim Oates,2 Kerry Goulston,2 Craig Mellis1 1Central Clinical School, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia; 2Sydney Medical School, The University of Sydney, Sydney, NSW, Australia Background: Bedside teaching lies at the heart of medical education. The learning environment afforded to students during clinical tutorials contributes substantially to their knowledge, thinking, and learning. Situated cognition theory posits that the depth and breadth of the students' learning experience is dependent upon the attitude of the clinical teacher, the structure of the tutorial, and the understanding of tutorial and learning objectives. This theory provides a useful framework to conceptualize how students' experience within their clinical tutorials impacts their knowledge, thinking, and learning. Methods: The study was conducted with one cohort (n=301 of students who had completed year 1 of the medical program at Sydney Medical School in 2013. All students were asked to complete a three-part questionnaire regarding their perceptions of their clinical tutor's attributes, the consistency of the tutor, and the best features of the tutorials and need for improvement. Both quantitative and qualitative data were collected and analyzed using descriptive statistics. Results: The response rate to the questionnaire was 88% (265/301. Students perceived that their tutors displayed good communication skills and enthusiasm, encouraged their learning, and were empathetic toward patients. Fifty-two percent of students reported having the same communications tutor for the entire year, and 28% reported having the same physical examination tutor for the entire year. Students would like increased patient contact, greater structure within their tutorials, and greater alignment of teaching with the curriculum. Conclusion: Situated cognition theory provides a valuable lens to view students' experience of learning within the

CNC Turning Technician. A Competency-Based Instructional System.

Science.gov (United States)

Sloan, Kelly; Hilley, Robert

This competency-based curriculum guide for instructing students in using computer numerically controlled (CNC) turning machines is one of a series of instructional guides for the machinist field developed in Oklahoma. Although developed jointly with Baxter Technologies Corporation and oriented toward the Baxter Vo-Tec 2000 Future Builder CNC…

Preparation of the CNC/Ag/beeswax composites for enhancing antibacterial and water resistance properties of paper.

Science.gov (United States)

Liu, Kai; Liang, Hunan; Nasrallah, Joseph; Chen, Lihui; Huang, Liulian; Ni, Yonghao

2016-05-20

An effective method of preparing composites containing inorganic (Ag) and organic (beeswax) particles was established in this study. Ag nanoparticles were first immobilized on the cellulose nanocrystals (CNC) during the reduction of AgNO3 in the presence of CNC, then mixed with beeswax by high speed stirring. Scanning transmission electron microscopy (STEM) images indicated that Ag and beeswax particles were uniformly dispersed and stable in the network structure formed by CNC. Upon coating on a paper surface, a layer of beeswax film was evident based on scanning electron microscopy (SEM) images. The dynamic contact angle and antibacterial activity tests indicated that the contact angle of coated paper reached 113.06° and the growth inhibition of Escherichia coli increased to 99.96%, respectively, at a coating amount of 21.53 g/m(2). When applied onto paper surface by coating, the CNC/Ag/beeswax composites can impact paper with antibacterial property and improved water resistance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Tutorial on beam current monitoring

International Nuclear Information System (INIS)

Webber, Robert C.

2000-01-01

This paper is a tutorial level review covering a wide range of aspects related to charged particle beam current measurement. The tutorial begins with a look at the characteristics of the beam as a signal source, the associated electromagnetic fields, the influence of the typical accelerator environment on those fields, and the usual means of modifying and controlling that environment to facilitate beam current measurement. Short descriptions of three quite different types of current monitors are presented and a quantitative review of the classical transformer circuit is given. Recognizing that environmental noise pick-up may present a large source of error in quantitative measurements, signal handling considerations are given considerable attention using real-life examples. An example of a successful transport line beam current monitor implementation is presented and the tutorial concludes with a few comments about signal processing and current monitor calibration issues

Pemanfaatan TKKS Sebagai Pengisi Komposit Epoxy Untuk Struktur Bergerak Mesin CNC Perkayuan

Directory of Open Access Journals (Sweden)

Farkhan

2017-04-01

Full Text Available Abstract CNC machinery is widely used at various kind of industrial sector to manufacture of art products up to satellite products. Instead of its massive utilization in automotive and electronic industry which mostly use metallic component, wood working industry has been using it to produces furniture’s, merchandises, and other house ware products which apply light weight non-metallic low density material. High removal rate in wood machining process needs high speed application due to its low density material; however most of wood working CNC machine is built on heavy steel structure for both its supporting structure and moving structure. In fact, the raw material is much lighter than the carrier itself. Its wasteful dynamic movement causes energy loses and vibrations that effect on machining accuracy, live of cutting tool, and productivity. This research applied new light weight composite material base on renewable resource of oil palm empty fruit bunch (EFB natural fiber as filler material combine with polymer epoxy as it’s matrix to be constructed as moving mechanical structure of high speed 3D CNC woodworking machine to improve its dynamic performance. Comparative analysis showed that it has better dynamic performance on high speed machining process compared with traditional cast iron material. Abstrak Mesin Perkakas CNC (Computerized Numerical Control digunakan luas oleh industri untuk memproduksi mulai dari benda-benda seni kerajinan hingga untuk membuat satelit. Selain pemanfaatannya secara besar-besaran di industri otomotif dan elektronika yang umumnya menggunakan komponen logam, industri perkayuan telah banyak menggunakannya untuk memproduksi mebel, barang kerajinan, dan peralatan rumah tangga lainnya dengan mengaplikasikan bahan bukan logam seperti kayu yang berberat jenis rendah dan ringan. Tingkat pemotongan yang tinggi pada proses permesinan kayu membutuhkan permesinan cepat akibat berat jenis bahannya yang rendah tersebut

An innovation on high-grade CNC machines tools for B-spline curve method of high-speed interpolation arithmetic

Science.gov (United States)

Zhang, Wanjun; Gao, Shanping; Cheng, Xiyan; Zhang, Feng

2017-04-01

A novel on high-grade CNC machines tools for B Spline curve method of High-speed interpolation arithmetic is introduced. In the high-grade CNC machines tools CNC system existed the type value points is more trouble, the control precision is not strong and so on, In order to solve this problem. Through specific examples in matlab7.0 simulation result showed that that the interpolation error significantly reduced, the control precision is improved markedly, and satisfy the real-time interpolation of high speed, high accuracy requirements.

Online Hotseat Tutorials

DEFF Research Database (Denmark)

Bengtsen, Søren Smedegaard; Nørgård, Rikke Toft; Dalsgaard, Christian

. On the grounds of the developed pedagogical format, students elicit advanced academic competences such as being facilitators of critical dialogue, exhibiting knowledge stewardship, and taking on responsibility of relationship formation between students. These are traits we normally see only teachers......We present a design-based research experiment for developing a pedagogical format for supervision collectives called ’online hotseat tutorials.’ The format has been developed and tested within the MA Programme ICT-based educational design, Aarhus University 2014-2018. It has affinity to traditional......-up as well as the pedagogical intentions behind it is presented. Finally, we analyse the emerging forms of partnership within online hot seat tutorials, and we discuss the pedagogical implications for how to further inform, qualify and develop pedagogical formats for team-based supervision in higher...

Ruthenium(II) Complexes Containing Lutidine-Derived Pincer CNC Ligands: Synthesis, Structure, and Catalytic Hydrogenation of C-N bonds.

Science.gov (United States)

Hernández-Juárez, Martín; López-Serrano, Joaquín; Lara, Patricia; Morales-Cerón, Judith P; Vaquero, Mónica; Álvarez, Eleuterio; Salazar, Verónica; Suárez, Andrés

2015-05-11

A series of Ru complexes containing lutidine-derived pincer CNC ligands have been prepared by transmetalation with the corresponding silver-carbene derivatives. Characterization of these derivatives shows both mer and fac coordination of the CNC ligands depending on the wingtips of the N-heterocyclic carbene fragments. In the presence of tBuOK, the Ru-CNC complexes are active in the hydrogenation of a series of imines. In addition, these complexes catalyze the reversible hydrogenation of phenantridine. Detailed NMR spectroscopic studies have shown the capability of the CNC ligand to be deprotonated and get involved in ligand-assisted activation of dihydrogen. More interestingly, upon deprotonation, the Ru-CNC complex 5 e(BF4 ) is able to add aldimines to the metal-ligand framework to yield an amido complex. Finally, investigation of the mechanism of the hydrogenation of imines has been carried out by means of DFT calculations. The calculated mechanism involves outer-sphere stepwise hydrogen transfer to the C-N bond assisted either by the pincer ligand or a second coordinated H2 molecule. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Design and Implementation of 3 Axis CNC Router for Computer Aided Manufacturing Courses

Directory of Open Access Journals (Sweden)

Aktan Mehmet Emin

2016-01-01

Full Text Available In this paper, it is intended to make the mechanical design of 3 axis Computer Numerical Control (CNC router with linear joints, production of electronic control interface cards and drivers and manufacturing of CNC router system which is a combination of mechanics and electronics. At the same time, interface program has been prepared to control router via USB. The router was developed for educational purpose. In some vocational schools and universities, Computer Aided Manufacturing (CAM courses are though rather theoretical. This situation cause ineffective and temporary learning. Moreover, students at schools which have the opportunity to apply for these systems can face with various dangerous accidents. Because of this situation, these students start to get knowledge about this system for the first time. For the first steps of CNC education, using smaller and less dangerous systems will be easier. A new concept CNC machine and its user interface suitable and profitable for education have been completely designed and realized during this study. To test the validity of the hypothesis which the benefits that may exist on the educational life, enhanced traditional education method with the contribution of the designed machine has been practiced on CAM course students for a semester. At the end of the semester, the new method applied students were more successful in the rate of 27.36 percent both in terms of verbal comprehension and exam grades.

Cr(OH)3-NPs-CNC hybrid nanocomposite: a sorbent for adsorptive removal of methylene blue and malachite green from solutions.

Science.gov (United States)

Nekouei, Farzin; Nekouei, Shahram; Keshtpour, Farzaneh; Noorizadeh, Hossein; Wang, Shaobin

2017-11-01

In this article, Cr(OH) 3 nanoparticle-modified cellulose nanocrystal (CNC) as a novel hybrid nanocomposite (Cr(OH) 3 -NPs-CNC) was prepared by a simple procedure and used as a sorbent for adsorptive removal of methylene blue (MB) and malachite green (MG) from aqueous solution. Different kinetic models were tested, and the pseudo-second-order kinetic model was found more suitable for the MB and MG adsorption processes. The BET and Langmuir models were more suitable for the adsorption processes of MB and MG. Thermodynamic studies suggested that the adsorption of MB and MG onto Cr(OH) 3 -NPs-CNC nanocomposite was a spontaneous and endothermic process. The maximum adsorption capacities for MB and MG were reached 106 and 104 mg/g, respectively, which were almost two times higher than unmodified CNC. The chemical stability and leaching tests of the Cr(OH) 3 -NPs-CNC hybrid nanocomposite showed that only small amounts of chromium were leached into the solution.

Multi-objective optimization model of CNC machining to minimize processing time and environmental impact

Science.gov (United States)

Hamada, Aulia; Rosyidi, Cucuk Nur; Jauhari, Wakhid Ahmad

2017-11-01

Minimizing processing time in a production system can increase the efficiency of a manufacturing company. Processing time are influenced by application of modern technology and machining parameter. Application of modern technology can be apply by use of CNC machining, one of the machining process can be done with a CNC machining is turning. However, the machining parameters not only affect the processing time but also affect the environmental impact. Hence, optimization model is needed to optimize the machining parameters to minimize the processing time and environmental impact. This research developed a multi-objective optimization to minimize the processing time and environmental impact in CNC turning process which will result in optimal decision variables of cutting speed and feed rate. Environmental impact is converted from environmental burden through the use of eco-indicator 99. The model were solved by using OptQuest optimization software from Oracle Crystal Ball.

Advocacy and IPR, tutorial 4

CERN Multimedia

CERN. Geneva

2005-01-01

With open access and repositories assuming a high profile some may question whether advocacy is still necessary. Those involved in the business of setting up and populating repositories are aware that in the majority of institutions there is still a great need for advocacy. This tutorial will give participants an opportunity to discuss different advocacy methods and approaches, including the 'top down' and 'bottom up' approach, publicity methods and the opportunities offered by funding body positions on open access. Participants will have the opportunity to share experiences of what works and what doesn't. The advocacy role often encompasses responsibility for advising academics on IPR issues. This is a particularly critical area where repository staff are engaged in depositing content on behalf of academics. The tutorial will offer an opportunity to discuss the IPR issues encountered by those managing repositories. The tutorial will draw on the experience of participants who have been engaged in advocacy act...

Pseudo-random tool paths for CNC sub-aperture polishing and other applications.

Science.gov (United States)

Dunn, Christina R; Walker, David D

2008-11-10

In this paper we first contrast classical and CNC polishing techniques in regard to the repetitiveness of the machine motions. We then present a pseudo-random tool path for use with CNC sub-aperture polishing techniques and report polishing results from equivalent random and raster tool-paths. The random tool-path used - the unicursal random tool-path - employs a random seed to generate a pattern which never crosses itself. Because of this property, this tool-path is directly compatible with dwell time maps for corrective polishing. The tool-path can be used to polish any continuous area of any boundary shape, including surfaces with interior perforations.

Historical Text Comprehension Reflective Tutorial Dialogue System

Science.gov (United States)

Grigoriadou, Maria; Tsaganou, Grammatiki; Cavoura, Theodora

2005-01-01

The Reflective Tutorial Dialogue System (ReTuDiS) is a system for learner modelling historical text comprehension through reflective dialogue. The system infers learners' cognitive profiles and constructs their learner models. Based on the learner model the system plans the appropriate--personalized for learners--reflective tutorial dialogue in…

Interactions between Lactobacillus sakei and CNC (Staphylococcus xylosus and Kocuria varians) and their influence on proteolytic activity.

Science.gov (United States)

Tremonte, P; Reale, A; Di Renzo, T; Tipaldi, L; Di Luccia, A; Coppola, R; Sorrentino, E; Succi, M

2010-11-01

To evaluate interactions between Lactobacillus sakei and coagulase negative cocci (CNC) (Staphylococcus xylosus and Kocuria varians) and to investigate the influence of these interactions on their own proteolytic activity. Interactions occurring between strains of Lact. sakei and CNC were assessed by spectrophotometric analysis. The growth of 35 strains of Lact. sakei, used as indicators, was compared to that obtained combining the same strains with growing cells or cell-free supernatants of 20 CNC (18 Staph. xylosus and 2 K. varians). The proteolytic activity expressed by single strains or by their combinations was assessed on sarcoplasmic protein extracts by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The results evidenced that interactions are able to affect not only the growth but also the in vitro proteolytic activity of Lact. sakei and CNC used in combination. A relationship between the presence of interactions among useful strains and the strength of technological characteristics, such as proteolysis, was defined. The study highlighted that CNC are able to stimulate the growth of some Lact. sakei strains. At the same time, this interaction positively influences the proteolytic activity of strains used in combination. Given the importance of proteolysis during the ripening of fermented meats, this phenomenon should be taken into account to select meat starter cultures. © 2010 The Authors. © 2010 The Society for Applied Microbiology.

The genre tutorial and social networks terminology

Directory of Open Access Journals (Sweden)

Márcio Sales Santiago

2014-02-01

Full Text Available This paper analyzes the terminology in the Internet social networks tutorials. A tutorial is a specialized text, full of terms, aiming to teach an individual or group of individuals who need some guidelines to operationalize a computerized tool, such as a social network. It is necessary to identify linguistic and terminological characteristics from the specialized lexical units in this digital genre. Social networks terminology is described and exemplified here. The results show that it is possible to refer to two specific terminologies in tutorials which help to determine the terminological profile of the thematic area, specifically from the point of view of denomination.

Optimization of machining parameters of hard porcelain on a CNC ...

African Journals Online (AJOL)

Optimization of machining parameters of hard porcelain on a CNC machine by Taguchi-and RSM method. ... Journal Home > Vol 10, No 1 (2018) > ... The conduct of experiments was made by employing the Taguchi's L27 Orthogonal array to ...

Alginate based nanocomposite for microencapsulation of probiotic: Effect of cellulose nanocrystal (CNC) and lecithin.

Science.gov (United States)

Huq, Tanzina; Fraschini, Carole; Khan, Avik; Riedl, Bernard; Bouchard, Jean; Lacroix, Monique

2017-07-15

Probiotic (Lactobacillus rhamnosus ATCC 9595) was encapsulated in alginate-CNC-lecithin microbeads to produce nutraceutical microcapsules. Addition of CNC and lecithin in alginate microbeads (ACL-1) improved the viability of L. rhamnosus during gastric passage and storage. The compression strength of the freeze-dried ACL-1 microbeads improved 40% compared to alginate microbeads alone. Swelling studies revealed that addition of CNC and lecithin in alginate microbeads decreased (around 47%) the gastric fluid absorption but increased the dissolution time by 20min compared to alginate microbeads (A-0). During transition through the gastric passage, the viability of L. rhamnosus in dried ACL-1 microbeads was increased 37% as compared to A-0 based beads. At 25 and 4°C storage conditions, the viability of L. rhamnosus encapsulated in ACL-1 microbeads decreased by 1.23 and 1.08 log respectively, whereas the encapsulation with A-0 microbeads exhibited a 3.17 and 1.93 log reduction respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

Protocadherin PAPC is expressed in the CNC and can compensate for the loss of PCNS.

Science.gov (United States)

Schneider, Martina; Huang, Chaolie; Becker, Sarah F S; Gradl, Dietmar; Wedlich, Doris

2014-02-01

Protocadherins represent the biggest subgroup within the cadherin superfamily of transmembrane glycoproteins. In contrast to classical type I cadherins, protocadherins in general exhibit only moderate adhesive activity. During embryogenesis, they are involved in cell signaling and regulate diverse morphogenetic processes, including morphogenetic movements during gastrulation and neural crest migration. The two protocadherins paraxial protocadherin (PAPC) and axial protocadherin (AXPC) are indispensable for proper gastrulation movements in Xenopus and zebrafish. The closest relative PCNS instead, is required for neural crest and somite formation. Here, we show that cranial neural crest (CNC) cells in addition to PCNS express PAPC, but not AXPC. Overexpression of PAPC resulted in comparable migration defects as knockdown of PCNS. Moreover, reconstitution experiments revealed that PAPC is able to replace PCNS in CNC cells, indicating that both protocadherins can regulate CNC migration. Copyright © 2013 Wiley Periodicals, Inc.

Writing learning cases for an information literacy tutorial

OpenAIRE

Gunhild Austrheim

2010-01-01

The research and writing processes are often hidden mysteries to our students. A key point in the online tutorial Search and Write (Søk and Skriv) has been to supply our students with tools to handle these processes. Learning cases embedded in the tutorial allow us to demonstrate a variety of working techniques and to better cater for a diverse student population. The tutorial can be used as an independent resource for students and as a teaching aid for both library sessions on inform...

Optical sensor platform based on cellulose nanocrystals (CNC) - 4'-(hexyloxy)-4-biphenylcarbonitrile (HOBC) bi-phase nematic liquid crystal composite films.

Science.gov (United States)

Santos, Moliria V; Tercjak, Agnieszka; Gutierrez, Junkal; Barud, Hernane S; Napoli, Mariana; Nalin, Marcelo; Ribeiro, Sidney J L

2017-07-15

The preparation of composite materials has gained tremendous attention due to the potential synergy of the combined materials. Here we fabricate novel thermal/electrical responsive photonic composite films combining cellulose nanocrystals (CNC) with a low molecular weight nematic liquid crystal (NLC), 4'-(hexyloxy)-4-biphenylcarbonitrile (HOBC). The obtained composite material combines both intense structural coloration of photonic cellulose and thermal and conductive properties of NLC. Scanning electron microscopy (SEM) results confirmed that liquid crystals coated CNC films maintain chiral nematic structure characteristic of CNC film and simultaneously, transversal cross-section scanning electron microscopy images indicated penetration of liquid crystals through the CNC layers. Investigated composite film maintain NLC optical properties being switchable as a function of temperature during heating/cooling cycles. The relationship between the morphology and thermoresponsive in the micro/nanostructured materials was investigated by using transmission optical microscopy (TOM). Conductive response of the composite films was proved by Electrostatic force microscopy (EFM) measurement. Designed thermo- and electro-responsive materials open novel simple pathway of fabrication of CNC-based materials with tunable properties. Copyright © 2017. Published by Elsevier Ltd.

The SIKS/BiGGrid Big Data Tutorial

NARCIS (Netherlands)

Hiemstra, Djoerd; Lammerts, Evert; de Vries, A.P.

2011-01-01

The School for Information and Knowledge Systems SIKS and the Dutch e-science grid BiG Grid organized a new two-day tutorial on Big Data at the University of Twente on 30 November and 1 December 2011, just preceding the Dutch-Belgian Database Day. The tutorial is on top of some exciting new

Audio-Tutorial Instruction: A Strategy For Teaching Introductory College Geology.

Science.gov (United States)

Fenner, Peter; Andrews, Ted F.

The rationale of audio-tutorial instruction is discussed, and the history and development of the audio-tutorial botany program at Purdue University is described. Audio-tutorial programs in geology at eleven colleges and one school are described, illustrating several ways in which programs have been developed and integrated into courses. Programs…

The effect of cellulose nanocrystal (CNC) from rattan biomass as filler and citric acid as co-plasticizer on tensile properties of sago starch biocomposite

Science.gov (United States)

Nasution, Halimatuddahliana; Harahap, Hamidah; Afandy, Yayang; Fath, M. Thoriq Al

2017-11-01

Biocomposite containing cellulose nanocrystals (CNC) from rattan biomass as fillers and citric acid as co-plasticizer. Rattan biomass is a fiber waste from processing industry of rattan which contains 37.6% cellulose. Isolation of alpha cellulose from rattan biomass was prepared by using three stages: delignification, alkalization, and bleaching. It was delignificated with 3.5% HNO3 and NaNO2, precipitated with 17.5% NaOH, bleaching process with 10% H2O2. The preparation of CNC includes acid hydrolysis using 45% H2SO4 and followed by mechanical processes of ultrasonication, centrifugation, and filtration with a dialysis membrane. Biocomposite was prepared using a solution casting method, which includes 1-4 wt % CNC as fillers, 10-40 wt% citric acid as co-plasticizer and 30 wt% glycerol as plasticizer. The results of TGA, SEM and XRD characteristic of CNC show that CNC has low residue mass, rod like and network like shape with crystallinity index 84.46%. Biocomposite characteristic consists of SEM, tensile strength and elongation at break. The resultshows that biocomposites by addition of CNC and citric acid have a smooth surface and homogeneous distribution of fillers. The tensile strength of biocomposites was increased by addition CNC and citric acid. The addition of CNC decreases the elongation at break but by addition of citric acid, the elongation at break was increased.

Are computer numerical control (CNC)-manufactured patient-specific metal templates available for posterior thoracic pedicle screw insertion? Feasibility and accuracy evaluation.

Science.gov (United States)

Kong, Xiangxue; Tang, Lei; Ye, Qiang; Huang, Wenhua; Li, Jianyi

2017-11-01

Accurate and safe posterior thoracic pedicle insertion (PTPI) remains a challenge. Patient-specific drill templates (PDTs) created by rapid prototyping (RP) can assist in posterior thoracic pedicle insertion, but pose biocompatibility risks. The aims of this study were to develop alternative PDTs with computer numerical control (CNC) and assess their feasibility and accuracy in assisting PTPI. Preoperative CT images of 31 cadaveric thoracic vertebras were obtained and then the optimal pedicle screw trajectories were planned. The PDTs with optimal screw trajectories were randomly assigned to be designed and manufactured by CNC or RP in each vertebra. With the guide of the CNC- or RP-manufactured PDTs, the appropriate screws were inserted into the pedicles. Postoperative CT scans were performed to analyze any deviations at entry point and midpoint of the pedicles. The CNC group was found to be significant manufacture-time-shortening, and cost-decreasing, when compared with the RP group (P  0.05). The screw positions were grade 0 in 90.3% and grade 1 in 9.7% of the cases in the CNC group and grade 0 in 93.5% and grade 1 in 6.5% of the cases in the RP group (P = 0.641). CNC-manufactured PDTs are viable for assisting in PTPI with good feasibility and accuracy.

Captivate MenuBuilder: Creating an Online Tutorial for Teaching Software

Science.gov (United States)

Yelinek, Kathryn; Tarnowski, Lynn; Hannon, Patricia; Oliver, Susan

2008-01-01

In this article, the authors, students in an instructional technology graduate course, describe a process to create an online tutorial for teaching software. They created the tutorial for a cyber school's use. Five tutorial modules were linked together through one menu screen using the MenuBuilder feature in the Adobe Captivate program. The…

Video and HTML: Testing Online Tutorial Formats with Biology Students

Science.gov (United States)

Craig, Cindy L.; Friehs, Curt G.

2013-01-01

This study compared two common types of online information literacy tutorials: a streaming media tutorial using animation and narration and a text-based tutorial with static images. Nine sections of an undergraduate biology lab class (234 students total) were instructed by a librarian on how to use the BIOSIS Previews database. Three sections…

Rossiter-McLaughlin observations of 55 Cnc e

DEFF Research Database (Denmark)

Lopez-Morales, Mercedes; Triaud, Amaury H. M. J.; Rodler, Florian

2014-01-01

We present Rossiter-McLaughlin observations of the transiting super-Earth 55 Cnc e collected during six transit events between 2012 January and 2013 November with HARPS and HARPS-N. We detect no radial velocity signal above 35 cm s–1 (3σ) and confine the stellar v sin i to 0.2 ± 0.5 km s–1. The s...

Caregiver's satisfaction with a video tutorial for shoulder dystocia management algorithm.

Science.gov (United States)

Youssef, A; Salsi, G; Ragusa, A; Ghi, T; Pacella, G; Rizzo, N; Pilu, G

2015-01-01

In our questionnaire, a video tutorial illustrating the management of shoulder dystocia was considered by health personnel as a useful complementary training tool. We prepared a 5-min video tutorial on the management of shoulder dystocia, using a simulator that includes maternal pelvic and baby models. We performed a survey among obstetric personnel in order to assess their opinion on the tutorial by inviting them to watch the video tutorial and answer an online questionnaire. Five multiple-choice questions were set, focusing on the video's main objectives: clarity, simplicity and usefulness. Following the collection of answers, global and category-weighted analyses were conducted for each question. Out of 956 invitations sent, 482 (50.4%) answered the survey. More than 90% of all categories found the video tutorial to be clinically relevant and clear. For revising the management of shoulder dystocia most obstetric personnel would use the video tutorial together with traditional textbooks. In conclusion, our video tutorial was considered by health personnel as a useful complementary training tool.

Mail2Print online tutorial

CERN Multimedia

CERN. Geneva

2016-01-01

Mail2print is a feature which allows you to send documents to a printer by mail. This tutorial (text attached to the event page) explains how to use this service. Content owner: Vincent Nicolas Bippus Presenter: Pedro Augusto de Freitas Batista Tell us what you think via e-learning.support at cern.ch More tutorials in the e-learning collection of the CERN Document Server (CDS) https://cds.cern.ch/collection/E-learning%20modules?ln=en All info about the CERN rapid e-learning project is linked from http://twiki.cern.ch/ELearning  

Fidget with Widgets: CNC Activity Introduces the Flatbed Router

Science.gov (United States)

Tryon, Daniel V.

2006-01-01

The computer numerical control (CNC) flatbed router is a powerful tool and a must-have piece of equipment for any technology education program in which students will produce a product--whether it involves Manufacturing, Materials Processing, or any of the vast array of Project Lead the Way courses. This article describes an activity--producing a…

Catalytic hydrogenation of CO2 to formates by lutidine-derived Ru-CNC pincer complex : theoretical insight into unrealized potential

NARCIS (Netherlands)

Filonenko, G.; Smykowski, D.; Szyja, B.M.; Li, G.; Szczygiel, J.; Hensen, E.J.M.; Pidko, E.A.

2015-01-01

Metal-ligand cooperative properties of a bis-N-heterocyclic carbene ruthenium CNC-pincer catalyst and its activity in CO2 hydrogenation to formates were studied by DFT calculations complemented by NMR spectroscopy and kinetic measurements. The dearomatized Ru-CNC* pincer (1*) is significantly more

Dynamical systems on networks a tutorial

CERN Document Server

Porter, Mason A

2016-01-01

This volume is a tutorial for the study of dynamical systems on networks. It discusses both methodology and models, including spreading models for social and biological contagions. The authors focus especially on “simple” situations that are analytically tractable, because they are insightful and provide useful springboards for the study of more complicated scenarios. This tutorial, which also includes key pointers to the literature, should be helpful for junior and senior undergraduate students, graduate students, and researchers from mathematics, physics, and engineering who seek to study dynamical systems on networks but who may not have prior experience with graph theory or networks. Mason A. Porter is Professor of Nonlinear and Complex Systems at the Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, University of Oxford, UK. He is also a member of the CABDyN Complexity Centre and a Tutorial Fellow of Somerville College. James P. Gleeson is Professor of Industrial and Appli...

Web-tutorials in context

DEFF Research Database (Denmark)

Lund, Haakon; Pors, Niels Ole

2012-01-01

Purpose – The purpose of the research is to investigate Norwegian web‐tutorials in contexts consisting of organizational issues and different forms of usability in relation to students’ perception and use of the system. Further, the research investigates the usefulness of the concepts concerning...... affordances and different forms of usability. Design/methodology/approach – The research has employed a variety of data‐collection methods including interviews with librarians, interviews and focus group interviews with students, coupled with tests of their capabilities using the systems. A detailed research...... the tutorials as part of the requirements. Further, examples of organizational amnesia are discussed, pointing to the necessity for leadership support and systematic knowledge sharing. System Usability Scores are analysed in relation to solution of tasks and interesting relations are analysed. The perceptions...

Online Pedagogical Tutorial Tactics Optimization Using Genetic-Based Reinforcement Learning.

Science.gov (United States)

Lin, Hsuan-Ta; Lee, Po-Ming; Hsiao, Tzu-Chien

2015-01-01

Tutorial tactics are policies for an Intelligent Tutoring System (ITS) to decide the next action when there are multiple actions available. Recent research has demonstrated that when the learning contents were controlled so as to be the same, different tutorial tactics would make difference in students' learning gains. However, the Reinforcement Learning (RL) techniques that were used in previous studies to induce tutorial tactics are insufficient when encountering large problems and hence were used in offline manners. Therefore, we introduced a Genetic-Based Reinforcement Learning (GBML) approach to induce tutorial tactics in an online-learning manner without basing on any preexisting dataset. The introduced method can learn a set of rules from the environment in a manner similar to RL. It includes a genetic-based optimizer for rule discovery task by generating new rules from the old ones. This increases the scalability of a RL learner for larger problems. The results support our hypothesis about the capability of the GBML method to induce tutorial tactics. This suggests that the GBML method should be favorable in developing real-world ITS applications in the domain of tutorial tactics induction.

ROOT Tutorial for Summer Students

CERN Multimedia

CERN. Geneva; Piparo, Danilo

2015-01-01

ROOT is a "batteries-included" tool kit for data analysis, storage and visualization. It is widely used in High Energy Physics and other disciplines such as Biology, Finance and Astrophysics. This event is an introductory tutorial to ROOT and comprises a front lecture and hands on exercises. IMPORTANT NOTE: The tutorial is based on ROOT 6.04 and NOT on the ROOT5 series.  IMPORTANT NOTE: if you have ROOT 6.04 installed on your laptop, you will not need to install any virtual machine. The instructions showing how to install the virtual machine on which you can find ROOT 6.04 can be found under "Material" on this page.

Interdisciplinary, Application-Oriented Tutorials: Design, Implementation, and Evaluation

Science.gov (United States)

Herman, Carolyn; Casiday, Rachel E.; Deppe, Roberta K.; Gilbertson, Michelle; Spees, William M.; Holten, Dewey; Frey, Regina F.

2005-01-01

Fifteen application-oriented chemical tutorials were developed out of which thirteen are currently in use in the general chemistry lab rotary curriculum for chemistry students at Washington University from 1998 to 2000. The central philosophy of the tutorial that the students learn to combine information from variety of sources like science…

Complexity of CNC transcription factors as revealed by gene targeting of the Nrf3 locus.

Science.gov (United States)

Derjuga, Anna; Gourley, Tania S; Holm, Teresa M; Heng, Henry H Q; Shivdasani, Ramesh A; Ahmed, Rafi; Andrews, Nancy C; Blank, Volker

2004-04-01

Cap'n'collar (CNC) family basic leucine zipper transcription factors play crucial roles in the regulation of mammalian gene expression and development. To determine the in vivo function of the CNC protein Nrf3 (NF-E2-related factor 3), we generated mice deficient in this transcription factor. We performed targeted disruption of two Nrf3 exons coding for CNC homology, basic DNA-binding, and leucine zipper dimerization domains. Nrf3 null mice developed normally and revealed no obvious phenotypic differences compared to wild-type animals. Nrf3(-/-) mice were fertile, and gross anatomy as well as behavior appeared normal. The mice showed normal age progression and did not show any apparent additional phenotype during their life span. We observed no differences in various blood parameters and chemistry values. We infected wild-type and Nrf3(-/-) mice with acute lymphocytic choriomeningitis virus and found no differences in these animals with respect to their number of virus-specific CD8 and CD4 T cells as well as their B-lymphocyte response. To determine whether the mild phenotype of Nrf3 null animals is due to functional redundancy, we generated mice deficient in multiple CNC factors. Contrary to our expectations, an absence of Nrf3 does not seem to cause additional lethality in compound Nrf3(-/-)/Nrf2(-/-) and Nrf3(-/-)/p45(-/-) mice. We hypothesize that the role of Nrf3 in vivo may become apparent only after appropriate challenge to the mice.

Intellectual Control System of Processing on CNC Machines

OpenAIRE

Nekrasov, R. Y.; Lasukov, Aleksandr Aleksandrovich; Starikov, A. I.; Soloviev, I. V.; Bekareva, O. V.

2016-01-01

Scientific and technical progress makes great demands for quality of engineering production. The priority is to ensure metalworking equipment with required dimensional accuracy during the entire period of operation at minimum manufacturing costs. In article considered the problem of increasing of accuracy of processing products on CNC. The authors offers a solution to the problem by providing compensating adjustment in the trajectory of the cutting tool and machining mode. The necessity of cr...

Dealing with Conflicts on Knowledge in Tutorial Groups

Science.gov (United States)

Aarnio, Matti; Lindblom-Ylanne, Sari; Nieminen, Juha; Pyorala, Eeva

2013-01-01

The aim of our study was to gain understanding of different types of conflicts on knowledge in the discussions of problem-based learning tutorial groups, and how such conflicts are dealt with. We examined first-year medical and dental students' (N = 33) conflicts on knowledge in four videotaped reporting phase tutorials. A coding scheme was…

Keyboard with Universal Communication Protocol Applied to CNC Machine

Directory of Open Access Journals (Sweden)

Mejía-Ugalde Mario

2014-04-01

Full Text Available This article describes the use of a universal communication protocol for industrial keyboard based microcontroller applied to computer numerically controlled (CNC machine. The main difference among the keyboard manufacturers is that each manufacturer has its own programming of source code, producing a different communication protocol, generating an improper interpretation of the function established. The above results in commercial industrial keyboards which are expensive and incompatible in their connection with different machines. In the present work the protocol allows to connect the designed universal keyboard and the standard keyboard of the PC at the same time, it is compatible with all the computers through the communications USB, AT or PS/2, to use in CNC machines, with extension to other machines such as robots, blowing, injection molding machines and others. The advantages of this design include its easy reprogramming, decreased costs, manipulation of various machine functions and easy expansion of entry and exit signals. The results obtained of performance tests were satisfactory, because each key has the programmed and reprogrammed facility in different ways, generating codes for different functions, depending on the application where it is required to be used.

Developing and Testing a Video Tutorial for Software Training

NARCIS (Netherlands)

van der Meij, Hans

2014-01-01

Purpose: Video tutorials for software training are rapidly becoming popular. A set of dedicated guidelines for the construction of such tutorials was recently advanced in Technical Communication (Van der Meij & Van der Meij, 2013). The present study set out to assess the cognitive and motivational

Writing learning cases for an information literacy tutorial

Directory of Open Access Journals (Sweden)

Gunhild Austrheim

2010-09-01

Full Text Available The research and writing processes are often hidden mysteries to our students. A key point in the online tutorial Search and Write (Søk and Skriv has been to supply our students with tools to handle these processes. Learning cases embedded in the tutorial allow us to demonstrate a variety of working techniques and to better cater for a diverse student population. The tutorial can be used as an independent resource for students and as a teaching aid for both library sessions on information literacy and for faculty-led sessions on academic writing. Our tutorial is available in Norwegian and in English and thereby the tutorial can be used with both local and international students. An online tutorial is aimed at all students and therefore the information literacy content is of a general kind. The pedagogical foundation for the Search and Write tutorial is in contextual learning. Adding context to our general content has been important to us and we decided to develop learning cases for this purpose. In our online tutorial we have developed three sample student blogs, Kuhlthau’s information search process functions as a template in structuring the students’ stories. The blogs are learning cases, developed with the intent of illustrating various aspects of academic writing tasks. The blog stories are idealized and touch upon many of the known stumbling stones for student writers. Contextualising the search and write process like this let us explore the diversity of student assignments and from various fields of study. When our real-life students use Search and Write they may use their own research question as a point of departure. They can read the blog stories and relate these stories to their own experiences. They can use the How to brainstorm-tips provided in Sofie’s blog. Christian’s use of tutors, library staff and his writing group can provide guidance on who to ask for help. For students writing literature reviews Oda’s systematic

Community Earth System Model (CESM) Tutorial 2016 Final Report

Energy Technology Data Exchange (ETDEWEB)

Lamarque, Jean-Francois [Univ. Corporation for Atmospheric Research (UCAR) and National Center for Atmospheric Research (NCAR) and Climate and Global Dynamics Laboratory (CGD), Boulder, CO (United States)

2017-05-09

For the 2016 tutorial, NCAR/CGD requested a total budget of $70,000 split equally between DOE and NSF. The funds were used to support student participation (travel, lodging, per diem, etc.). Lectures and practical session support was primarily provided by local participants at no additional cost (see list below). The seventh annual Community Earth System Model (CESM) tutorial (2016) for students and early career scientists was held 8 – 12 August 2016. As has been the case over the last few years, this event was extremely successful and there was greater demand than could be met. There was continued interest in support of the NSF’s EaSM Infrastructure awards, to train these awardees in the application of the CESM. Based on suggestions from previous tutorial participants, the 2016 tutorial experience again provided direct connection to Yellowstone for each individual participant (rather than pairs), and used the NCAR Mesa Library. The 2016 tutorial included lectures on simulating the climate system and practical sessions on running CESM, modifying components, and analyzing data. These were targeted to the graduate student level. In addition, specific talks (“Application” talks) were introduced this year to provide participants with some in-depth knowledge of some specific aspects of CESM.

Valence shell threshold photoelectron spectroscopy of the CHxCN (x = 0-2) and CNC radicals.

Science.gov (United States)

Garcia, Gustavo A; Krüger, Julia; Gans, Bérenger; Falvo, Cyril; Coudert, Laurent H; Loison, Jean-Christophe

2017-07-07

We present the photoelectron spectroscopy of four radical species, CH x CN (x = 0-2) and CNC, formed in a microwave discharge flow-tube reactor by consecutive H abstractions from CH 3 CN (CH x CN + F → CH x-1 CN + HF (x = 1-3)). The spectra were obtained combining tunable vacuum ultraviolet synchrotron radiation with double imaging electron/ion coincidence techniques, which yielded mass-selected threshold photoelectron spectra. The results obtained for H 2 CCN complement existing ones while for the other radicals the data represent the first observation of their (single-photon) ionizing transitions. In the case of H 2 CCN, Franck-Condon calculations have been performed in order to assign the vibrational structure of the X + 1 A 1 ←X 2 B 1 ionizing transition. A similar treatment for the HCCN, CCN, and CNC radicals appeared to be more complicated mainly because a Renner-Teller effect strongly affects the vibrational levels of the ground electronic state of the HCCN + , CCN, and CNC species. Nevertheless, the first adiabatic ionization energies of these radicals are reported and compared to our ab initio calculated values, leading to new values for enthalpies of formation (Δ f H 298 0 (HCCN + (X 2 A ' ))=1517±12kJmol -1 ,Δ f H 298 0 (CCN(X 2 Π))=682±13kJmol -1 , and Δ f H 298 0 (CNC(X 2 Πg))=676±12kJmol -1 ), which are of fundamental importance for astrochemistry.

Effectiveness of Tutorials for Introductory Physics in Argentinean high schools

Science.gov (United States)

Benegas, J.; Flores, J. Sirur

2014-06-01

This longitudinal study reports the results of a replication of Tutorials in Introductory Physics in high schools of a Latin-American country. The main objective of this study was to examine the suitability of Tutorials for local science education reform. Conceptual learning of simple resistive electric circuits was determined by the application of the single-response multiple-choice test "Determining and Interpreting Resistive Electric Circuits Concepts Test" (DIRECT) to high school classes taught with Tutorials and traditional instruction. The study included state and privately run schools of different socioeconomic profiles, without formal laboratory space and equipment, in classes of mixed-gender and female-only students, taught by novice and experienced instructors. Results systematically show that student learning is significantly higher in the Tutorials classes compared with traditional teaching for all of the studied conditions. The results also show that long-term learning (one year after instruction) in the Tutorials classes is highly satisfactory, very similar to the performance of the samples of college students used to develop the test DIRECT. On the contrary, students following traditional instruction returned one year after instruction to the poor performance (students attending seven universities in Spain and four Latin-American countries. Some replication and adaptation problems and difficulties of this experience are noted, as well as recommendations for successful use of Tutorials in high schools of similar educational systems.

Comparison of two interactive tutorial methods: results from a medical college in Karachi.

Science.gov (United States)

Rehan, Rabiya; Farooqi, Lubna; Khan, Hira; Rehman, Rehana

2017-02-01

To compare perception of students on usefulness of interactive tutorials and clinically-oriented problem-solving tutorials. The cross-sectional study was carried out from January 2012 to November 2013 at Bahria University Medical and Dental College, Karachi. The perception of medical students on usefulness of interactive tutorials and clinically-oriented problem-solving tutorials was acquired through a questionnaire distributed to medical students having completed the first two years of studies. The responses on various aspects of learning of physiology were acquired on a scale of poor, good or excellent. The learning abilities and acquired skills were compared in terms of not at all, to some extent, and to great extent. Data was analysed using SPSS 15. Of the hundred students initially enrolled, complete response was obtained from 83(83%). Of them, 47(57%) were females. There was significant difference in understanding of structure and function by clinically-oriented problem-solving tutorials (p=0.04). The students preferred clinically-oriented problem-solving tutorials as far as understating of difficult concepts was concerned (pskills were improved by interactive tutorials (p=0.02) whereas clinical reasoning skills acquired by clinically-oriented problem-solving tutorials was found to be significantly better (pskills were acquired more by clinically-oriented problem-solving tutorials that helped in better understanding of structure and functions.

3D technology in fine art and craft exploring 3D printing, scanning, sculpting and milling

CERN Document Server

Mongeon, Bridgette

2015-01-01

The possibilities for creation are endless with 3D printing, sculpting, scanning, and milling, and new opportunities are popping up faster than artists can keep up with them. 3D Technology in Fine Art and Craft takes the mystery out of these exciting new processes by demonstrating how to navigate their digital components and showing their real world applications. Artists will learn to incorporate these new technologies into their studio work and see their creations come to life in a physical form never before possible. Featuring a primer on 3D basics for beginners,interviews, tutorials, and ar

The normal conformal Cartan connection and the Bach tensor

International Nuclear Information System (INIS)

Korzynski, Mikolaj; Lewandowski, Jerzy

2003-01-01

The goal of this paper is to express the Bach tensor of a four-dimensional conformal geometry of an arbitrary signature by the Cartan normal conformal (CNC) connection. We show that the Bach tensor can be identified with the Yang-Mills current of the connection. It follows from that result that a conformal geometry whose CNC connection is reducible in an appropriate way has a degenerate Bach tensor. As an example we study the case of a CNC connection which admits a twisting covariantly constant twistor field. This class of conformal geometries of this property is known as given by the Fefferman metric tensors. We use our result to calculate the Bach tensor of an arbitrary Fefferman metric and show that it is proportional to the tensorial square of the four-fold eigenvector of the Weyl tensor. Finally, we solve the Yang-Mills equations imposed on the CNC connection for all the homogeneous Fefferman metrics. The only solution is the Nurowski-Plebanski metric

MacSelfService online tutorial

CERN Multimedia

CERN. Geneva

2016-01-01

Mac Self-Service is a functionality within the Mac Desktop Service built and maintained to empower CERN users by giving them easy access to applications and configurations through the Self-Service application. This tutorial (text attached to the event page) explains how to install Mac Self-Service and how to use it to install applications and printers. Content owner: Vincent Nicolas Bippus Presenter: Pedro Augusto de Freitas Batista Tell us what you think via e-learning.support at cern.ch More tutorials in the e-learning collection of the CERN Document Server (CDS) https://cds.cern.ch/collection/E-learning%20modules?ln=en All info about the CERN rapid e-learning project is linked from http://twiki.cern.ch/ELearning  

A test of the design of a video tutorial for software training

NARCIS (Netherlands)

van der Meij, Jan; van der Meij, Hans

2015-01-01

The effectiveness of a video tutorial versus a paper-based tutorial for software training has yet to be established. Mixed outcomes from the empirical studies to date suggest that for a video tutorial to outperform its paper-based counterpart, the former should be crafted so that it addresses the

Improving the University Tutorial.

Science.gov (United States)

Stanton, Harry E.

1982-01-01

Frequently, tutorial or seminar members take no part in discussion, a feature considered essential to this teaching method. Tutors may be largely responsible by dominating discussion. Student participation can be increased by varying teaching methods; reducing discussion group size, brainstorming, idea development techniques, and student…

Tutorial to SARAH

CERN Document Server

Staub, Florian

2016-01-01

I give in this brief tutorial a short practical introduction to the Mathematica package SARAH. First, it is shown how an existing model file can be changed to implement a new model in SARAH. In the second part, masses, vertices and renormalisation group equations are calculated with SARAH. Finally, the main commands to generate model files and output for other tools are summarised.

A CNC Sheetmetal Fabrication System for Production of Ships Ventilation Components and Flatwork

National Research Council Canada - National Science Library

Galie, Thomas R; Blais, David R

1981-01-01

.... By utilizing computer graphics technology and Computer Numeric Control (CNC) machine tools, it is possible to reduce the manhours required for fabrication of ventilation and flatwork by as much as 40 percent...

Comprehensive reliability allocation method for CNC lathes based on cubic transformed functions of failure mode and effects analysis

Science.gov (United States)

Yang, Zhou; Zhu, Yunpeng; Ren, Hongrui; Zhang, Yimin

2015-03-01

Reliability allocation of computerized numerical controlled(CNC) lathes is very important in industry. Traditional allocation methods only focus on high-failure rate components rather than moderate failure rate components, which is not applicable in some conditions. Aiming at solving the problem of CNC lathes reliability allocating, a comprehensive reliability allocation method based on cubic transformed functions of failure modes and effects analysis(FMEA) is presented. Firstly, conventional reliability allocation methods are introduced. Then the limitations of direct combination of comprehensive allocation method with the exponential transformed FMEA method are investigated. Subsequently, a cubic transformed function is established in order to overcome these limitations. Properties of the new transformed functions are discussed by considering the failure severity and the failure occurrence. Designers can choose appropriate transform amplitudes according to their requirements. Finally, a CNC lathe and a spindle system are used as an example to verify the new allocation method. Seven criteria are considered to compare the results of the new method with traditional methods. The allocation results indicate that the new method is more flexible than traditional methods. By employing the new cubic transformed function, the method covers a wider range of problems in CNC reliability allocation without losing the advantages of traditional methods.

On modeling the CNC end milling characteristics of Al-7075/WC powder metallurgy composites

Science.gov (United States)

Hanuman, N. S. V. N.; Rao, P. Gangadhara; Kumar, B. Sudheer; Karthik, N.

2017-07-01

Surface finish and material removal rate are two important factors in the manufacturing which affect acceptability of the product which in turn reflects on the profitability of the organization. The worth of the production setup to produce the components with high material removal rate (MRR) without sacrificing the surface requirements can play vital role in sustainability and profitability of the organization. In this paper, the effect of process parameters on metal removal rate and surface roughness has been investigated in milling of Al7075-MMC with WC as reinforcement element. Cutting speed, feed and depth of cut have been taken as input factors in three level response surface methodologies used for experimentation. Mathematical models have been developed using response surface methodology to predict surface finish, and metal removal rate in term of machining parameters. Depth of cut and feed rate are found to be a dominant parameter for surface roughness; whereas feed rate mainly affects the metal removal rate. The results of mathematical models have been compared with the experimental and found to be in good agreement. The results of predicted model can be used in selection of process parameters to insure desired quality and improved productivity.

Computer Tutorial Programs in Physics.

Science.gov (United States)

Faughn, Jerry; Kuhn, Karl

1979-01-01

Describes a series of computer tutorial programs which are intended to help college students in introductory physics courses. Information about these programs, which are either calculus or algebra-trig based, is presented. (HM)

Biology and Nursing Students’ Perceptions of a Web-based Information Literacy Tutorial

Directory of Open Access Journals (Sweden)

Sharon Weiner

2012-04-01

Full Text Available This study assessed student perceptions about an online information literacy tutorial, CORE (Comprehensive Online Research Education, to plan for the next generation of tutorials. The CORE tutorial includes seven modules: “Planning Your Project,” “Topic Exploration,” “Types of Information,” “Search Tools,” “Search Strategies,” “Evaluating Sources,” and “Copyright, Plagiarism, and Citing Sources.” First-year students in biology and nursing courses responded to a survey after they completed the CORE modules. The students liked learning through an online tutorial. They thought that the tutorial could be improved with shorter modules and the addition of video and audio content. Few students reported learning important information from the “Copyright, Plagiarism, and Citing Sources,” “Evaluating Resources,” and “Types of Information” modules. They suggested topics for additional tutorials: how to use library databases and Microsoft Excel; how to evaluate the quality of information, how to cite references in a bibliography, and how to find statistics.

Evaluating the role of web-based tutorials in educational practice

DEFF Research Database (Denmark)

Moring, Camilla; Schreiber, Trine

The paper describes and discusses a two step analysis for evaluating web based information literacy tutorials in educational practice. In a recent evaluation project the authors used the analysis to examine three web based tutorials developed by three different academic libraries in Norway. Firstly...... of the analysis focuses on user reception and meaning negotiation. In combination the two different analyses strengthen the evaluation of how web-tutorials as communicative acts become meaningful to users, and how this meaning is negotiated in relation to an educational practice. This approach can be recommended...

Automatic Generation of Setup for CNC Spring Coiler Based on Case-based Reasoning

Institute of Scientific and Technical Information of China (English)

KU Xiangchen; WANG Runxiao; LI Jishun; WANG Dongbo

2006-01-01

When producing special-shape spring in CNC spring coiler, the setup of the coiler is often a manual work using a trial-and-error method. As a result, the setup of coiler consumes so much time and becomes the bottleneck of the spring production process. In order to cope with this situation, this paper proposes an automatic generation system of setup for CNC spring coiler using case-based reasoning (CBR). The core of the study contains: (1) integrated reasoning model of CBR system;(2) spatial shape describe of special-shape spring based on feature;(3) coiling case representation using shape feature matrix; and (4) case similarity measure algorithm. The automatic generation system has implemented with C++ Builder 6.0 and is helpful in improving the automaticity and efficiency of spring coiler.

Desain dan Implementasi Sistem Kendali CNC Router Menggunakan PC untuk Flame Cutting Machine

Directory of Open Access Journals (Sweden)

Roni Permana Saputra

2012-03-01

Full Text Available This paper focuses on design of router control systems based on computer numerical control (CNC using personal computer (PC implemented in flame cutting machine (FCM. NC-Code entered into the computer translated to be a command signal sent by the PC to a microcontroller to control the end effector’s movement alongthe X and Y axis simultaneously based on linear and circular interpolations calculation on the PC. This control system is implemented on FCM by connecting the output control of the microcontroller with the driver actuator of the FCM in the form of a DC motor. The obtained result is in the form of a CNC router control system prototype to be implemented in the FCM which is capable to perform linear interpolation and circular interpolation. 

Modeling of optimization strategies in the incremental CNC sheet metal forming process

International Nuclear Information System (INIS)

Bambach, M.; Hirt, G.; Ames, J.

2004-01-01

Incremental CNC sheet forming (ISF) is a relatively new sheet metal forming process for small batch production and prototyping. In ISF, a blank is shaped by the CNC movements of a simple tool in combination with a simplified die. The standard forming strategies in ISF entail two major drawbacks: (i) the inherent forming kinematics set limits on the maximum wall angle that can be formed with ISF. (ii) since elastic parts of the imposed deformation can currently not be accounted for in CNC code generation, the standard strategies can lead to undesired deviations between the target and the sample geometry.Several enhancements have recently been put forward to overcome the above limitations, among them a multistage forming strategy to manufacture steep flanges, and a correction algorithm to improve the geometric accuracy. Both strategies have been successful in improving the forming of simple parts. However, the high experimental effort to empirically optimize the tool paths motivates the use of process modeling techniques.This paper deals with finite element modeling of the ISF process. In particular, the outcome of different multistage strategies is modeled and compared to collated experimental results regarding aspects such as sheet thickness and the onset of wrinkling. Moreover, the feasibility of modeling the geometry of a part is investigated as this is of major importance with respect to optimizing the geometric accuracy. Experimental validation is achieved by optical deformation measurement that gives the local displacements and strains of the sheet during forming as benchmark quantities for the simulation

Fatigue and Model Analysis of the CNC Cylindrical Grinder

OpenAIRE

Lin Jui-Chang; Lin Cheng-Jen

2016-01-01

The purpose of this study is to lower deviation of workpiece by meeting high stability and rigidity to prevent the resonance in producing procedure of the CNC universal cylindrical grinding machine. Using finite element analysis software ABAQUS in grinder machine tools for numerical simulation of several analyses for the following: structural rigidity analysis, optimized design, vibration frequency analysis and fatigue damage analysis. This work aims on state of the transmission of outer diam...

Making Accounting Tutorials Enjoyable

Science.gov (United States)

Bargate, Karen

2018-01-01

This paper emanates from a case study which focussed on 15 Managerial Accounting and Financial Management (MAFM) students' "enjoyment" of learning MAFM in an 18-week Writing Intensive Tutorial (WIT) programme. Interactive Qualitative Analysis (IQA) was used for the research design and as a data analysis tool. Following IQA protocols…

Effectiveness of Tutorials for Introductory Physics in Argentinean high schools

Directory of Open Access Journals (Sweden)

J. Benegas

2014-03-01

Full Text Available This longitudinal study reports the results of a replication of Tutorials in Introductory Physics in high schools of a Latin-American country. The main objective of this study was to examine the suitability of Tutorials for local science education reform. Conceptual learning of simple resistive electric circuits was determined by the application of the single-response multiple-choice test “Determining and Interpreting Resistive Electric Circuits Concepts Test” (DIRECT to high school classes taught with Tutorials and traditional instruction. The study included state and privately run schools of different socioeconomic profiles, without formal laboratory space and equipment, in classes of mixed-gender and female-only students, taught by novice and experienced instructors. Results systematically show that student learning is significantly higher in the Tutorials classes compared with traditional teaching for all of the studied conditions. The results also show that long-term learning (one year after instruction in the Tutorials classes is highly satisfactory, very similar to the performance of the samples of college students used to develop the test DIRECT. On the contrary, students following traditional instruction returned one year after instruction to the poor performance (<20% shown before instruction, a result compatible with the very low level of conceptual knowledge of basic physics recently determined by a systematic study of first-year students attending seven universities in Spain and four Latin-American countries. Some replication and adaptation problems and difficulties of this experience are noted, as well as recommendations for successful use of Tutorials in high schools of similar educational systems.

Design and Assessment of Online, Interactive Tutorials That Teach Science Process Skills.

Science.gov (United States)

Kramer, Maxwell; Olson, Dalay; Walker, J D

2018-06-01

Explicit emphasis on teaching science process skills leads to both gains in the skills themselves and, strikingly, deeper understanding of content. Here, we created and tested a series of online, interactive tutorials with the goal of helping undergraduate students develop science process skills. We designed the tutorials in accordance with evidence-based multimedia design principles and student feedback from usability testing. We then tested the efficacy of the tutorials in an introductory undergraduate biology class. On the basis of a multivariate ordinary least-squares regression model, students who received the tutorials are predicted to score 0.82 points higher on a 15-point science process skill assessment than their peers who received traditional textbook instruction on the same topic. This moderate but significant impact indicates that well-designed online tutorials can be more effective than traditional ways of teaching science process skills to undergraduate students. We also found trends that suggest the tutorials are especially effective for nonnative English-speaking students. However, due to a limited sample size, we were unable to confirm that these trends occurred due to more than just variation in the student group sampled.

Hazardous Solvent Substitution Data System tutorial

International Nuclear Information System (INIS)

Twitchell, K.E.; Skinner, N.L.

1993-07-01

This manual is the tutorial for the Hazardous Solvent Substitution Data System (HSSDS), an online, comprehensive system of information on alternatives to hazardous solvents and related subjects. The HSSDS data base contains product information, material safety data sheets, toxicity reports, usage reports, biodegradable data, product chemical element lists, and background information on solvents. HSSDS use TOPIC reg-sign to search for information based on a query defined by the user. TOPIC provides a full text retrieval of unstructured source documents. In this tutorial, a series of lessons is provided that guides the user through basic steps common to most queries performed with HSSDS. Instructions are provided for both window-based and character-based applications

New series of ORACLE tutorials, March-June 2006

CERN Multimedia

Catherine Delamare

2006-01-01

The IT DES Oracle Support team is pleased to announce the new series of Oracle tutorials with the proposed schedule: Thursday 20 April - SQL I - Eva Dafonte Perez Thursday 27 April - SQL II - Lucia Moreno Lopez Thursday 4 May - Architecture - Montse Collados Thursday 11 May - Tuning - Michal Kwiatek Thursday 1 June - PL/SQL I - Eva Dafonte Perez Thursday 8 June - PL/SQL II - Nilo Segura Thursday 15 June - Oracle Tools and Bindings with languages - Eric Grancher, Nilo Segura These tutorials will take place in the IT Auditorium (bldg. 31/3-004) starting at 10:00. The average duration will be 1 hour plus time for questions. There is no need to register in advance. You can access the previous 2002-2003 sessions at http://it-des.web.cern.ch/IT-DES/DIS/oracle/tutorials.html If you need more information, please contact Catherine.Delamare@cern.ch

Understanding Medical Words: A Tutorial from the National Library of Medicine

Science.gov (United States)

... page: https://medlineplus.gov/medicalwords.html Understanding Medical Words: A Tutorial from the National Library of Medicine ... enable JavaScript. This tutorial teaches you about medical words. You'll learn about how to put together ...

A tutorial on Fisher information

NARCIS (Netherlands)

Ly, A.; Marsman, M.; Verhagen, J.; Grasman, R.P.P.P.; Wagenmakers, E.-M.

2017-01-01

In many statistical applications that concern mathematical psychologists, the concept of Fisher information plays an important role. In this tutorial we clarify the concept of Fisher information as it manifests itself across three different statistical paradigms. First, in the frequentist paradigm,

Would You Watch It? Creating Effective and Engaging Video Tutorials

Science.gov (United States)

Martin, Nichole A.; Martin, Ross

2015-01-01

Video tutorials are a common form of library instruction used with distance learners. This paper combines professional experience and literature reviews from multiple disciplines to provide a contextual overview of recommendations and findings for effective and engaging videos. The tools for tutorials appear in five main categories: screencasts,…

Online interactive tutorials for creating graphs with excel 2007 or 2010.

Science.gov (United States)

Vanselow, Nicholas R; Bourret, Jason C

2012-01-01

Graphic display of clinical data is a useful tool for the behavior-analytic clinician. However, graphs can sometimes be difficult to create. We describe how to access and use an online interactive tutorial that teaches the user to create a variety of graphs often used by behavior analysts. Three tutorials are provided that cover the basics of Microsoft Excel 2007 or 2010, creating graphs for clinical purposes, and creating graphs for research purposes. The uses for this interactive tutorial and other similar programs are discussed.

You Tube Video Genres. Amateur how-to Videos Versus Professional Tutorials

Directory of Open Access Journals (Sweden)

Andreea Mogoș

2015-12-01

Full Text Available In spite of the fact that there is a vast literature on traditional textual and visual genre classifications, the categorization of web content is still a difficult task, because this medium is fluid, unstable and fast-paced on one hand and, on the other hand, the genre classifications are socially constructed through the tagging process and the interactions (commenting, rating, chatting. This paper focuses on YouTube tutorials and aims to compare video tutorials produced by professionals with amateur video tutorials.

Subtitled video tutorials, an accessible teaching material

Directory of Open Access Journals (Sweden)

Luis Bengochea

2012-11-01

Full Text Available The use of short-lived audio-visual tutorials constitutes an educational resource very attractive for young students, widely familiar with this type of format similar to YouTube clips. Considered as "learning pills", these tutorials are intended to strengthen the understanding of complex concepts that because their dynamic nature can’t be represented through texts or diagrams. However, the inclusion of this type of content in eLearning platforms presents accessibility problems for students with visual or hearing disabilities. This paper describes this problem and shows the way in which a teacher could add captions and subtitles to their videos.

Success of the Tutorial Program in Biochemistry at The Federal University of Vi

Directory of Open Access Journals (Sweden)

M.C. Baracat-Pereira

2004-05-01

Full Text Available Institutionalized at UFV in 2001, the Tutorial Program in Biochemistry aims to reduce the une-venness of basic prior knowledge among the students enrolled in regular Biochemistry courses. Thework methodology has been periodically evaluated and rened in order to overcome identied pro-blems. Thus, the objective of this study was to evaluate the Tutorial Program based on the stu-dentsachievement, to show implemented modications and proposed alternatives to adjust methodo-logies. The student-nal-grades were obtained from UFV les. Questionnaires were applied to thePrograms students at the end of each semester. Suggestions and criticism from tutors and coordinatingprofessors were discussed at weekly meetings. Along six semesters (2001-2003, a leveling o of thetutorial students was observed with the attending students (S, minimum of 75% attendance, averagegrade 71.3 that got grades close to the average of no-tutorial students (average grade 71.5. For thetutorial students with attendance below the required minimum (N, the average grade was 58.8. Thefailure rate for grade S students (7.4% was lower then that for no-tutorial students (9.9% and forgrade N students (27.9%. Based on the lled out questionnaire from tutorial students, we observeas follows: 96.7% stated that it is eective to participate in the Program and 79.9% modied theirstudy approach. Among the modications implemented in the Program, are as folows: 1 Increase inthe number of tutorial groups (from 4 to 6; 2 Reduction in the number of volunteer-students, givingpriority to students with decient prior knowledge in pre-requisite-disciplines; and 3 Time reductionof tutorial sessions (from 3 to 2h weekly, with smaller groups and exercise classes. Thus, the observedmotivation, the leveling o and the lower failure rate of the S grade tutorial students indicated that theTutorial Program at UFV is improving and reaching its objectives.

New series of ORACLE tutorials, March-June 2006

CERN Multimedia

Catherine Delamare

2006-01-01

The IT DES Oracle Support team is pleased to announce the new series of Oracle tutorials with the proposed schedule: Thursday 30 March - Design - Arash Khodabandeh Thursday 20 April - SQL I - Eva Dafonte Perez Thursday 27 April - SQL II - Lucia Moreno Lopez Thursday 4 May - Architecture - Montse Collados Thursday 11 May - Tuning - Michal Kwiatek Thursday 1 June - PL/SQL I - Eva Dafonte Perez Thursday 8 June - PL/SQL II - Nilo Segura Thursday 15 June - Oracle Tools and Bindings with languages - Eric Grancher, Nilo Segura These tutorials will take place in the IT Auditorium (bldg. 31/3-004) starting at 10:00. The average duration will be 1 hour plus time for questions. There is no need to register in advance. You can access the previous 2002-2003 sessions at http://it-des.web.cern.ch/IT-DES/DIS/oracle/tutorials.html If you need more information, please contact Catherine.Delamare@cern.ch

Effect of the milling conditions on the degree of amorphization of selenium by milling in a planetary ball mill

International Nuclear Information System (INIS)

Ksiazek, K; Wacke, S; Gorecki, T; Gorecki, Cz

2007-01-01

The effect of the milling parameters (rotation speed of the milling device and duration of milling) on the phase composition of the products of milling of fully crystalline selenium has been investigated. The milling was conducted using a planetary micromill and the phase composition of the milling products was determined by differential thermal analysis. It has been found that ball milling leads to the partial amorphization of the starting crystalline material. The content of amorphous phase in the milling products depends, in a rather complicated way, on the milling parameters. At the milling parameters adopted in the present study, the milling product was never fully amorphous. The complicated way the milling parameters affect the content of amorphous phase in the milling products is a result of competition of two processes: amorphization due to deformation and refinement of grains of milled material and crystallization of the already produced amorphous material at the cost of heat evolved in the milling vial during the milling process

A Web-Based Comparative Genomics Tutorial for Investigating Microbial Genomes

Directory of Open Access Journals (Sweden)

Michael Strong

2009-12-01

Full Text Available As the number of completely sequenced microbial genomes continues to rise at an impressive rate, it is important to prepare students with the skills necessary to investigate microorganisms at the genomic level. As a part of the core curriculum for first-year graduate students in the biological sciences, we have implemented a web-based tutorial to introduce students to the fields of comparative and functional genomics. The tutorial focuses on recent computational methods for identifying functionally linked genes and proteins on a genome-wide scale and was used to introduce students to the Rosetta Stone, Phylogenetic Profile, conserved Gene Neighbor, and Operon computational methods. Students learned to use a number of publicly available web servers and databases to identify functionally linked genes in the Escherichia coli genome, with emphasis on genome organization and operon structure. The overall effectiveness of the tutorial was assessed based on student evaluations and homework assignments. The tutorial is available to other educators at http://www.doe-mbi.ucla.edu/~strong/m253.php.

Tutorial on architectural acoustics

Science.gov (United States)

Shaw, Neil; Talaske, Rick; Bistafa, Sylvio

2002-11-01

This tutorial is intended to provide an overview of current knowledge and practice in architectural acoustics. Topics covered will include basic concepts and history, acoustics of small rooms (small rooms for speech such as classrooms and meeting rooms, music studios, small critical listening spaces such as home theatres) and the acoustics of large rooms (larger assembly halls, auditoria, and performance halls).

Tutorial Video Series: Using Stakeholder Outreach to Increase ...

Science.gov (United States)

The limited amount of toxicity data on thousands of chemicals found in consumer products has led to the development of research endeavors such as the U.S. EPA’s Toxicity Forecaster (ToxCast). ToxCast uses high-throughput screening technology to evaluate thousands of chemicals for potential toxicity. At the end of 2013, U.S. EPA released ToxCast chemical data on almost 2,000 chemicals through the interactive Chemical Safety for Sustainability (iCSS) Dashboard. The iCSS Dashboard provides public access to the high-throughput screening data that can be used to inform the evaluation of the safety of chemicals. U.S. EPA recognized early in the development of ToxCast that stakeholder outreach was needed in order to translate the complex scientific information featured in the iCSS Dashboard and data, with the goal of educating the diverse user community through targeted efforts to increase data usage and analysis. Through survey feedback and the request of stakeholders, a series of tutorial videos to demonstrate how to access and use the data has been planned, and the first video of the series has been released to guide data usage. This presentation will describe the video tutorial strategy including an overview of: 1) Stakeholder outreach goals and approach; 2) Planning, production, and dissemination of tutorial videos; 3) Overview of Survey Feedback; 4) Overview of tutorial video usage statistics and usage of the ToxCast data. This stakeholder-outreach approach

Communicating Big Data with the Public via Tutorials

Science.gov (United States)

Montgomery, Michele

2015-08-01

Although numerical models that researchers use to analyze large astronomy data sets may be easily found on NASA websites, tutorials on how to use these models and understanding the products of the models are lacking. Thus, communication with the public is ineffective. Where the public could easily engage with data and models to determine if their work and lives could be impacted, and if so, to plan accordingly, a lack of good tutorials typically results in the public waiting for a tweet, a post on Facebook, an announcement on a NASA webpage, an alert sent via text message or email, etc. An example is a solar flare or coronal mass ejection event that may impact GPS devices, the precision of which is heavily relied upon by several sectors of the public and military. To allow the public to engage in real time with solar data and NASA developed heliophysics software, we have developed tutorials. In this work, we present our tutorials made for NASA's Living With a Star Program on the such as Integrated Space Weather Analysis (ISWA) layout and the WSA-ENLIL-CONE Model to analyze a CME Evolution that occurred in 2010. We present our results and our analysis of the public's ability to understand the model's predictions of whether the event will impact Earth. By training the public to use the data and to understand model predictions, we turn passive recipients into engaged and self-supporting users of NASA data of space weather events.

Engaging undergraduate nursing students in face-to-face tutorials.

Science.gov (United States)

Elder, Ruth L; Lewis, Peter A; Windsor, Carol A; Wheeler, Margaret; Forster, Elizabeth; Foster, Joanne; Chapman, Helen

2011-09-01

Chronic nursing shortages have placed increasing pressure on many nursing schools to recruit greater numbers of students with the consequence of larger class sizes. Larger class sizes have the potential to lead to student disengagement. This paper describes a case study that examined the strategies used by a group of nursing lecturers to engage students and to overcome passivity in a Bachelor of Nursing programme. A non-participant observer attended 20 tutorials to observe five academics deliver four tutorials each. Academics were interviewed both individually and as a group following the completion of all tutorial observations. All observations, field notes, interviews and focus groups were coded separately and major themes identified. From this analysis two broad categories emerged: getting students involved; and engagement as a struggle. Academics used a wide variety of techniques to interest and involve students. Additionally, academics desired an equal relationship with students. They believed that both they and the students had some power to influence the dynamics of tutorials and that neither party had ultimate power. The findings of this study serve to re-emphasise past literature which suggests that to engage students, the academics must also engage. Copyright © 2011 Elsevier Ltd. All rights reserved.

Direct Trajectory Interpolation on the Surface using an Open CNC

OpenAIRE

Beudaert , Xavier; Lavernhe , Sylvain; Tournier , Christophe

2014-01-01

International audience; Free-form surfaces are used for many industrial applications from aeronautical parts, to molds or biomedical implants. In the common machining process, computer-aided manufacturing (CAM) software generates approximated tool paths because of the limitation induced by the input tool path format of the industrial CNC. Then, during the tool path interpolation, marks on finished surfaces can appear induced by non smooth feedrate planning. Managing the geometry of the tool p...

3D Printing device adaptable to Computer Numerical Control (CNC)

OpenAIRE

GARDAN , Julien; Danesi , F.; Roucoules , Lionel; Schneider , A.

2014-01-01

This article presents the development of a 3D printing device for the additive manufacturing adapted to a CNC machining. The application involves the integration of a specific printing head. Additive manufacturing technology is most commonly used for modeling, prototyping, tooling through an exclusive machine or 3D printer. A global review and analysis of technologies show the additive manufacturing presents little independent solutions [6][9]. The problem studied especially the additive manu...

The Neural-fuzzy Thermal Error Compensation Controller on CNC Machining Center

Science.gov (United States)

Tseng, Pai-Chung; Chen, Shen-Len

The geometric errors and structural thermal deformation are factors that influence the machining accuracy of Computer Numerical Control (CNC) machining center. Therefore, researchers pay attention to thermal error compensation technologies on CNC machine tools. Some real-time error compensation techniques have been successfully demonstrated in both laboratories and industrial sites. The compensation results still need to be enhanced. In this research, the neural-fuzzy theory has been conducted to derive a thermal prediction model. An IC-type thermometer has been used to detect the heat sources temperature variation. The thermal drifts are online measured by a touch-triggered probe with a standard bar. A thermal prediction model is then derived by neural-fuzzy theory based on the temperature variation and the thermal drifts. A Graphic User Interface (GUI) system is also built to conduct the user friendly operation interface with Insprise C++ Builder. The experimental results show that the thermal prediction model developed by neural-fuzzy theory methodology can improve machining accuracy from 80µm to 3µm. Comparison with the multi-variable linear regression analysis the compensation accuracy is increased from ±10µm to ±3µm.

A tutorial on the principles of harmonic intonation for trombonists

Science.gov (United States)

Keener, Michael Kenneth

A Tutorial on the Principles of Harmonic Intonation for Trombonists includes a manual containing background information, explanations of the principles of harmonic intonation, and printed musical examples for use in learning and practicing the concepts of harmonic intonation. An audio compact disk containing music files corresponding to the printed music completes the set. This tutorial is designed to allow performing musicians and students to practice intonation skills with the pitch-controlled music on the compact disc. The music on the CD was recorded in movable-comma just intonation, replicating performance parameters of wind, string, and vocal ensembles. The compact disc includes sixty tracks of ear-training exercises and interval studies with which to practice intonation perception and adjustment. Tuning notes and examples of equal-tempered intervals and just intervals are included on the CD. The intonation exercises consist of musical major scales, duets, trios, and quartet phrases to be referenced while playing the printed music. The CD tracks allow the performer to play scales in unison (or practice other harmonic intervals) or the missing part of the corresponding duet, trio, or quartet exercise. Instructions in the manual guide the user through a process that can help prepare musicians for more accurate musical ensemble performance. The contextual essay that accompanies the tutorial includes a description of the tutorial, a review of related literature, methodology of construction of the tutorial, evaluations and outcomes, conclusions and recommendations for further research, and a selected bibliography.

Proposal for tutorial: Resilience in carrier Ethernet transport

DEFF Research Database (Denmark)

Berger, Michael Stübert; Wessing, Henrik; Ruepp, Sarah Renée

2009-01-01

This tutorial addresses how Carrier Ethernet technologies can be used in the transport network to provide resilience to the packet layer. Carrier Ethernet networks based on PBB-TE and T-MPLS/MPLS-TP are strong candidates for reliable transport of triple-play services. These technologies offer...... of enhancements are still required to make Carrier Ethernet ready for large scale deployments of reliable point-to-multipoint services. The tutorial highlights the necessary enhancements and shows possible solutions and directions towards reliable multicast. Explicit focus is on OAM for multicast, where...

The undergraduate physics tutorial program at CSU Los Angeles assessment of utility and areas of interest

Science.gov (United States)

Avetyan, Smbat

The Physics Education Research (PER) group at the University of Washington have researched traditional teaching methods and found that students in introductory physics are lacking a conceptual understanding of the physics material. The solution they put forth is an interactive tutorial program designed to meet the lack of conceptual understanding. Since the tutorial programs inception at CSU Los Angeles in Fall 2006 no evaluation has been successfully undertaken therefore the effect of the tutorial program in the physics 200 series is deeply obscure to the department. The research has shed light on the tutorial program and brought into context its effectiveness on the overall physics 200 series courses at CSU Los Angeles. The researcher has addressed the following research questions, what overall effect does the tutorial program have on the Physics 200 series curriculum? What is the size and significance of gains attributable to the undergraduate calculus based Physics 200 series tutorial program at CSU Los Angeles? What can we learn from gains about individual weekly lessons from the Physics 200 series tutorial courses? What is the correlation of tutorial gains with student final course grades? Are the gains from the tutorial program different for genders? Is there a difference in gains based on the different students' colleges?

A Tutorial Design Process Applied to an Introductory Materials Engineering Course

Science.gov (United States)

Rosenblatt, Rebecca; Heckler, Andrew F.; Flores, Katharine

2013-01-01

We apply a "tutorial design process", which has proven to be successful for a number of physics topics, to design curricular materials or "tutorials" aimed at improving student understanding of important concepts in a university-level introductory materials science and engineering course. The process involves the identification…

A binary catalyst system of a cationic Ru-CNC pincer complex with an alkali metal salt for selective hydroboration of carbon dioxide.

Science.gov (United States)

Ng, Chee Koon; Wu, Jie; Hor, T S Andy; Luo, He-Kuan

2016-09-27

Binary catalyst systems comprising a cationic Ru-CNC pincer complex and an alkali metal salt were developed for selective hydroboration of CO 2 utilizing pinacolborane at r.t. and 1 atm CO 2 , with the combination of [Ru(CNC Bn )(CO) 2 (H)][PF 6 ] and KOCO 2 t Bu producing formoxyborane in 76% yield. A bicyclic catalytic mechanism was proposed and discussed.

An Improved Minimum Error Interpolator of CNC for General Curves Based on FPGA

Directory of Open Access Journals (Sweden)

Jiye HUANG

2014-05-01

Full Text Available This paper presents an improved minimum error interpolation algorithm for general curves generation in computer numerical control (CNC. Compared with the conventional interpolation algorithms such as the By-Point Comparison method, the Minimum- Error method and the Digital Differential Analyzer (DDA method, the proposed improved Minimum-Error interpolation algorithm can find a balance between accuracy and efficiency. The new algorithm is applicable for the curves of linear, circular, elliptical and parabolic. The proposed algorithm is realized on a field programmable gate array (FPGA with Verilog HDL language, and simulated by the ModelSim software, and finally verified on a two-axis CNC lathe. The algorithm has the following advantages: firstly, the maximum interpolation error is only half of the minimum step-size; and secondly the computing time is only two clock cycles of the FPGA. Simulations and actual tests have proved that the high accuracy and efficiency of the algorithm, which shows that it is highly suited for real-time applications.

Constant Cutting Force Control for CNC Machining Using Dynamic Characteristic-Based Fuzzy Controller

Directory of Open Access Journals (Sweden)

Hengli Liu

2015-01-01

Full Text Available This paper presents a dynamic characteristic-based fuzzy adaptive control algorithm (DCbFACA to avoid the influence of cutting force changing rapidly on the machining stability and precision. The cutting force is indirectly obtained in real time by monitoring and extraction of the motorized spindle current, the feed speed is fuzzy adjusted online, and the current was used as a feedback to control cutting force and maintain the machining process stable. Different from the traditional fuzzy control methods using the experience-based control rules, and according to the complex nonlinear characteristics of CNC machining, the power bond graph method is implemented to describe the dynamic characteristics of process, and then the appropriate variation relations are achieved between current and feed speed, and the control rules are optimized and established based on it. The numerical results indicated that DCbFACA can make the CNC machining process more stable and improve the machining precision.

The Nature of Reflective Practice and Emotional Intelligence in Tutorial Settings

Science.gov (United States)

Gill, Gobinder Singh

2014-01-01

The purpose of this paper was to assess the nature of reflective practice and emotional intelligence in tutorial settings. Following the completion of a self-report measure of emotional intelligence, practitioners incorporated a model of reflective practice into their tutorial sessions. Practitioners were instructed to utilise reflective practice…

ULTRACAM photometry of the ultracompact binaries V407 Vul and HM Cnc

NARCIS (Netherlands)

Barros, S.C.C.; Marsh, T.R.; Dhillon, V.S.; Groot, P.J.; Littlefair, S.; Nelemans, G.A.; Roelofs, G.H.A.; Steeghs, D.; Wheatley, P.J.

2007-01-01

V407 Vul (RXJ1914.4+2456) and HM Cnc (RXJ0806.3+1527) are X-ray emitting stars with X-ray light curves that are 100 per cent modulated on periods of 569 and 321 s, respectively. These periods are thought possibly to represent the orbital periods of close pairs of white dwarfs. In this paper we

Prognostics 101: A tutorial for particle filter-based prognostics algorithm using Matlab

International Nuclear Information System (INIS)

An, Dawn; Choi, Joo-Ho; Kim, Nam Ho

2013-01-01

This paper presents a Matlab-based tutorial for model-based prognostics, which combines a physical model with observed data to identify model parameters, from which the remaining useful life (RUL) can be predicted. Among many model-based prognostics algorithms, the particle filter is used in this tutorial for parameter estimation of damage or a degradation model. The tutorial is presented using a Matlab script with 62 lines, including detailed explanations. As examples, a battery degradation model and a crack growth model are used to explain the updating process of model parameters, damage progression, and RUL prediction. In order to illustrate the results, the RUL at an arbitrary cycle are predicted in the form of distribution along with the median and 90% prediction interval. This tutorial will be helpful for the beginners in prognostics to understand and use the prognostics method, and we hope it provides a standard of particle filter based prognostics. -- Highlights: ► Matlab-based tutorial for model-based prognostics is presented. ► A battery degradation model and a crack growth model are used as examples. ► The RUL at an arbitrary cycle are predicted using the particle filter

pFUnit 3.0 Tutorial Advanced

Science.gov (United States)

Clune, Tom

2014-01-01

This tutorial will introduce Fortran developers to unit-testing and test-driven development (TDD) using pFUnit. As with other unit-testing frameworks, pFUnit, simplifies the process of writing, collecting, and executing tests while providing clear diagnostic messages for failing tests. pFUnit specifically targets the development of scientific-technical software written in Fortran and includes customized features such as: assertions for multi-dimensional arrays, distributed (MPI) and thread-based (OpenMP) parallellism, and flexible parameterized tests.These sessions will include numerous examples and hands-on exercises that gradually build in complexity. Attendees are expected to have working knowledge of F90, but familiarity with object-oriented syntax in F2003 and MPI will be of benefit for the more advanced examples. By the end of the tutorial the audience should feel comfortable in applying pFUnit within their own development environment.

Using Structure-Based Organic Chemistry Online Tutorials with Automated Correction for Student Practice and Review

Science.gov (United States)

O'Sullivan, Timothy P.; Hargaden, Gra´inne C.

2014-01-01

This article describes the development and implementation of an open-access organic chemistry question bank for online tutorials and assessments at University College Cork and Dublin Institute of Technology. SOCOT (structure-based organic chemistry online tutorials) may be used to supplement traditional small-group tutorials, thereby allowing…

Effect of a gelatin-based edible coating containing cellulose nanocrystals (CNC) on the quality and nutrient retention of fresh strawberries during storage

Science.gov (United States)

Fakhouri, F. M.; Casari, A. C. A.; Mariano, M.; Yamashita, F.; Innocnentini Mei, L. H.; Soldi, V.; Martelli, S. M.

2014-08-01

Strawberry is a non-climacteric fruit with a very short postharvest shelf-life. Loss of quality in this fruit is mostly due to its relatively high metabolic activity and sensitivity to fungal decay, meanly grey mold (Botrytis cinerea). In this study, the ability of gelatin coatings containing cellulose nanocrystals (CNC) to extend the shelf-life of strawberry fruit (Fragaria ananassa) over 8 days were studied. The filmogenic solution was obtained by the hydration of 5 g of gelatin (GEL) in 100 mL of distillated water containing different amounts of CNC dispersion (10 mg CNC/g of GEL or 50 mg of CNC/g of GEL) for 1 hour at room temperature. After this period, the solution was heated to 70 °C and maintained at this temperature for 10 minutes. The plasticizer (glycerol) (10g/100g of the GEL) was then added with constant, gentle stirring in order to avoid forming air bubbles and also to avoid gelatin denaturation until complete homogenization. Strawberries (purchased at the local market) were immersed in the filmogenic solution for 1 minute and after coated were dried at 15 °C by 24 hours. The strawberries were then kept under refrigeration and characterized in terms of their properties (weight loss, ascorbic acid content, titratable acidity, water content). The results have shown that samples covered with GEL/CNC had a significant improvement in its shelf- life. For instance, for the control sample (without coating) the weight loss after 8 days of storage was around 65%, while covered samples loss in the range of 31-36%. Edible coating was also effective in the retention of ascorbic acid (AA) in the strawberries, while control sample presented a fast decay in the AA content, covered samples showed a slow decay in the AA concentration. Moreover, the use of GEL/CNC edible coating had an antimicrobial effect in the fruits.

Effect of a gelatin-based edible coating containing cellulose nanocrystals (CNC) on the quality and nutrient retention of fresh strawberries during storage

International Nuclear Information System (INIS)

Fakhouri, F M; Casari, A C A; Martelli, S M; Mariano, M; Soldi, V; Yamashita, F; Mei, L H Innocnentini

2014-01-01

Strawberry is a non-climacteric fruit with a very short postharvest shelf-life. Loss of quality in this fruit is mostly due to its relatively high metabolic activity and sensitivity to fungal decay, meanly grey mold (Botrytis cinerea). In this study, the ability of gelatin coatings containing cellulose nanocrystals (CNC) to extend the shelf-life of strawberry fruit (Fragaria ananassa) over 8 days were studied. The filmogenic solution was obtained by the hydration of 5 g of gelatin (GEL) in 100 mL of distillated water containing different amounts of CNC dispersion (10 mg CNC/g of GEL or 50 mg of CNC/g of GEL) for 1 hour at room temperature. After this period, the solution was heated to 70 °C and maintained at this temperature for 10 minutes. The plasticizer (glycerol) (10g/100g of the GEL) was then added with constant, gentle stirring in order to avoid forming air bubbles and also to avoid gelatin denaturation until complete homogenization. Strawberries (purchased at the local market) were immersed in the filmogenic solution for 1 minute and after coated were dried at 15 °C by 24 hours. The strawberries were then kept under refrigeration and characterized in terms of their properties (weight loss, ascorbic acid content, titratable acidity, water content). The results have shown that samples covered with GEL/CNC had a significant improvement in its shelf- life. For instance, for the control sample (without coating) the weight loss after 8 days of storage was around 65%, while covered samples loss in the range of 31-36%. Edible coating was also effective in the retention of ascorbic acid (AA) in the strawberries, while control sample presented a fast decay in the AA content, covered samples showed a slow decay in the AA concentration. Moreover, the use of GEL/CNC edible coating had an antimicrobial effect in the fruits

El control numérico computarizado en el desarrollo industrial Parte 2: desarrollo y aplicaciones del C.N.C.

OpenAIRE

Ruiz, Lino

2016-01-01

En la edición anterior nuestro principal énfasis fue el de presentar el control numérico computarizado (C.N.C.) como una alternativa tecnológica que pueda potenciar nuestro desarrollo industrial, por lo que describimos sus características principales y su incidencia en el trabajador. En el presente articulo nos enfocaremos, más al manejo de la información en las máquinas CNC, las tendencias actuales del desarrollo de las MHCNC y las tendencias industriales de nuestra época.

Tutorial on nuclear thermal propulsion safety for Mars

International Nuclear Information System (INIS)

Buden, D.

1992-01-01

Safety is the prime design requirement for nuclear thermal propulsion (NTP). It must be built in at the initiation of the design process. An understanding of safety concerns is fundamental to the development of nuclear rockets for manned missions to Mars and many other applications that will be enabled or greatly enhanced by the use of nuclear propulsion. To provide an understanding of the basic issues, a tutorial has been prepared. This tutorial covers a range of topics including safety requirements and approaches to meet these requirements, risk and safety analysis methodology, NERVA reliability and safety approach, and life cycle risk assessments

Intellectual Control System of Processing on CNC Machines

Science.gov (United States)

Nekrasov, R. Y.; Lasukov, A. A.; Starikov, A. I.; Soloviev, I. V.; Bekareva, O. V.

2016-04-01

Scientific and technical progress makes great demands for quality of engineering production. The priority is to ensure metalworking equipment with required dimensional accuracy during the entire period of operation at minimum manufacturing costs. In article considered the problem of increasing of accuracy of processing products on CNC. The authors offers a solution to the problem by providing compensating adjustment in the trajectory of the cutting tool and machining mode. The necessity of creation of mathematical models of processes behavior in an automated technological system operations (OATS). Based on the research, authors have proposed a generalized diagram of diagnosis and input operative correction and approximate mathematical models of individual processes of diagnosis.

An example of using CASPER tutorials for teaching knowledge of firmware development for FPGAs

International Nuclear Information System (INIS)

Pollak, A.W.

2015-01-01

We present an example of using CASPER tutorials for teaching purposes in Summer Schools and Workshops with participants from a variety of different academic backgrounds. Using the tutorials for laboratory exercises at the INFIERI Summer School 2014, we showed that the flexible nature provided by these tutorials has the advantage of providing high quality laboratory exercises for participants independent of their prior knowledge

Action perception and imitation : a tutorial

NARCIS (Netherlands)

Bekkering, H; Wohlschlager, A; Prinz, W; Hommel, B

2002-01-01

Currently, imitation, or performing an act after perceiving it, is in the focus of attention of researchers from many different disciplines. Although this tutorial attempts to provide some interdisciplinary background, it will concentrate on possible cognitive mechanisms that underlie imitation

CERN Technical Training 2007: IT3T - IT Technical Training Tutorials (Autumn 2007)

CERN Multimedia

2007-01-01

CERN Technical Training and the Internet Services group of the IT department (IT/IS) are jointly organizing a series of free tutorials, addressing some topics of common interest: the IT Technical Training Tutorials (IT3T). The first IT3T series will be offered in October 2007, in French, with the following schedule: IT3T/2007/1 "Introduction to Collaboration Workspaces using SharePoint", October 23rd , 14:30-16:00, Alexandre Lossent IT3T/2007/2 "What is new in Office 2007", October 25th, 14:30-15:30, Emmanuel Ormancey IT3T/2007/3 "Working with Windows Vista at CERN", October 30th, 14:30-15:30, Michal Kwiatek IT3T/2007/4 "Read your mail and more with Outlook 2007", November 1st, 14:30-15:30, Sebastien Dellabella All IT Technical Training Tutorials will take place in the Training Centre Auditorium (building 593, room 11), at 14h30. The tutorials are free of charge, but separate registration to each is required. Participation to any of the tutorials is open: attendance to any ...

Uranium milling costs

International Nuclear Information System (INIS)

Coleman, R.B.

1980-01-01

Basic process flowsheets are reviewed for conventional milling of US ores. Capital costs are presented for various mill capacities for one of the basic processes. Operating costs are shown for various mill capacities for all of the basic process flowsheets. The number of mills using, or planning to use, a particular process is reviewed. A summary of the estimated average milling costs for all operating US mills is shown

Hyperspectral image analysis. A tutorial

International Nuclear Information System (INIS)

Amigo, José Manuel; Babamoradi, Hamid; Elcoroaristizabal, Saioa

2015-01-01

This tutorial aims at providing guidelines and practical tools to assist with the analysis of hyperspectral images. Topics like hyperspectral image acquisition, image pre-processing, multivariate exploratory analysis, hyperspectral image resolution, classification and final digital image processing will be exposed, and some guidelines given and discussed. Due to the broad character of current applications and the vast number of multivariate methods available, this paper has focused on an industrial chemical framework to explain, in a step-wise manner, how to develop a classification methodology to differentiate between several types of plastics by using Near infrared hyperspectral imaging and Partial Least Squares – Discriminant Analysis. Thus, the reader is guided through every single step and oriented in order to adapt those strategies to the user's case. - Highlights: • Comprehensive tutorial of Hyperspectral Image analysis. • Hierarchical discrimination of six classes of plastics containing flame retardant. • Step by step guidelines to perform class-modeling on hyperspectral images. • Fusion of multivariate data analysis and digital image processing methods. • Promising methodology for real-time detection of plastics containing flame retardant.

Comparison of Interfacial Electron Transfer Efficiency in [Fe(ctpy)2]2+-TiO2 and [Fe(cCNC)2]2+-TiO2 Assemblies: Importance of Conformational Sampling.

Science.gov (United States)

Mukherjee, Sriparna; Liu, Chang; Jakubikova, Elena

2018-02-22

Fe(II)-polypyridines have limited applications as chromophores in dye-sensitized solar cells due to the short lifetimes (∼100 fs) of their photoactive metal-to-ligand charge transfer (MLCT) states formed upon photoexcitation. Recently, a 100-fold increase in the MLCT lifetime was observed in a [Fe(CNC) 2 ] 2+ complex (CNC = 2,6-bis(3-methylimidazole-1-ylidine)pyridine) which has strong σ-donating N-heterocyclic carbene ligand in comparison to the weaker field parent [Fe(tpy) 2 ] 2+ complex (tpy = 2,2':6',2″-terpyridine). This study utilizes density functional theory (DFT), time-dependent DFT, and quantum dynamics simulations to investigate the interfacial electron transfer (IET) in [Fe(cCNC) 2 ] 2+ (cCNC = 4'-carboxy-2,6-bis(3-methylimidazole-1-ylidine)pyridine) and [Fe(ctpy) 2 ] 2+ (ctpy = 4'-carboxy-2,2':6',2″-terpyridine) sensitized TiO 2 . Our results suggest that the replacement of tpy by CNC ligand does not significantly speed up the IET kinetics in the [Fe(cCNC) 2 ] 2+ -TiO 2 assembly in comparison to the [Fe(ctpy) 2 ] 2+ -TiO 2 analogue. The high IET efficiency in the [Fe(cCNC) 2 ] 2+ -TiO 2 assemblies is therefore due to longer lifetime of [Fe(cCNC) 2 ] 2+ photoactive 3 MLCT states rather than faster electron injection kinetics. It was also found that the inclusion of conformational sampling in the computational model is important for proper description of the IET processes in these systems, as the models relying on the use of only fully optimized structures may yield misleading results. The simulations presented in this work also illustrate various pitfalls of utilizing properties such as electronic coupling, number of available acceptor states, and driving force, as well as calculations based on Fermi's golden rule framework, to reach conclusions on the IET efficiency in dye-semiconductor systems.

Intelligent tutorial system for selftraining in tuning of control systems; Sistema tutorial inteligente para el autoentrenamiento en sintonizacion de sistemas de control

Energy Technology Data Exchange (ETDEWEB)

Romero Jimenez, Guillermo; Perez Ocampo, Maria Concepcion [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

1999-07-01

In this paper the design, development and validation of an intelligent tutorial system oriented to the instruction of techniques of tuning of control systems is described. This system is based on systems previously developed in the Simulation Unit of the Instituto de Investigaciones Electricas (IIE). The designed system accounts with four modules: of knowledge, the student model, of tutor and of interface, basic characteristics that allows to locate this system in the context of the intelligent tutorial systems. In this system in particular, the knowledge module was only modified, because advantage is taken of the existing structure to incorporate a new dominion of application: the one of the techniques of tuning of control systems. The system maintains the characteristic that it can also be used as a consultation system. In addition to the design and validation of the tutorial system, when following the methodology of processing the degree of generality of the developed system, was evaluated, taking into account the evaluation and quantification of metrics that the engineering software proposes. [Spanish] En este trabajo se describen el diseno, el desarrollo y la validacion de un sistema tutorial inteligente orientado a la instruccion de tecnicas de sintonizacion de sistemas de control. Este sistema esta basado en sistemas desarrollados anteriormente en la Unidad de Simulacion del Instituto de Investigaciones Electricas (IIE). El sistema disenado cuenta con cuatro modulos: de conocimiento, del modelo del estudiante, de tutor y de interfaz, caracteristica principal que permite ubicar a este sistema en el contexto de los sistemas tutoriales inteligentes. En este sistema en particular solo se modifica el modulo de conocimiento, pues se aprovecha la estructura existente para incorporar un nuevo dominio de aplicacion: el de las tecnicas de sintonizacion de sistemas de control. El sistema mantiene la caracteristica de que tambien puede utilizarse como un sistema de

AT Cnc: A SECOND DWARF NOVA WITH A CLASSICAL NOVA SHELL

International Nuclear Information System (INIS)

Shara, Michael M.; Mizusawa, Trisha; Zurek, David; Wehinger, Peter; Martin, Christopher D.; Neill, James D.; Forster, Karl; Seibert, Mark

2012-01-01

We are systematically surveying all known and suspected Z Cam-type dwarf novae for classical nova shells. This survey is motivated by the discovery of the largest known classical nova shell, which surrounds the archetypal dwarf nova Z Camelopardalis. The Z Cam shell demonstrates that at least some dwarf novae must have undergone classical nova eruptions in the past, and that at least some classical novae become dwarf novae long after their nova thermonuclear outbursts, in accord with the hibernation scenario of cataclysmic binaries. Here we report the detection of a fragmented 'shell', 3 arcmin in diameter, surrounding the dwarf nova AT Cancri. This second discovery demonstrates that nova shells surrounding Z Cam-type dwarf novae cannot be very rare. The shell geometry is suggestive of bipolar, conical ejection seen nearly pole-on. A spectrum of the brightest AT Cnc shell knot is similar to that of the ejecta of the classical nova GK Per, and of Z Cam, dominated by [N II] emission. Galaxy Evolution Explorer FUV imagery reveals a similar-sized, FUV-emitting shell. We determine a distance of 460 pc to AT Cnc, and an upper limit to its ejecta mass of ∼5 × 10 –5 M ☉ , typical of classical novae.

AT Cnc: A SECOND DWARF NOVA WITH A CLASSICAL NOVA SHELL

Energy Technology Data Exchange (ETDEWEB)

Shara, Michael M.; Mizusawa, Trisha; Zurek, David [Department of Astrophysics, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024-5192 (United States); Wehinger, Peter [Steward Observatory, the University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Martin, Christopher D.; Neill, James D.; Forster, Karl [Department of Physics, Math and Astronomy, California Institute of Technology, 1200 East California Boulevard, Mail Code 405-47, Pasadena, CA 91125 (United States); Seibert, Mark [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

2012-10-20

We are systematically surveying all known and suspected Z Cam-type dwarf novae for classical nova shells. This survey is motivated by the discovery of the largest known classical nova shell, which surrounds the archetypal dwarf nova Z Camelopardalis. The Z Cam shell demonstrates that at least some dwarf novae must have undergone classical nova eruptions in the past, and that at least some classical novae become dwarf novae long after their nova thermonuclear outbursts, in accord with the hibernation scenario of cataclysmic binaries. Here we report the detection of a fragmented 'shell', 3 arcmin in diameter, surrounding the dwarf nova AT Cancri. This second discovery demonstrates that nova shells surrounding Z Cam-type dwarf novae cannot be very rare. The shell geometry is suggestive of bipolar, conical ejection seen nearly pole-on. A spectrum of the brightest AT Cnc shell knot is similar to that of the ejecta of the classical nova GK Per, and of Z Cam, dominated by [N II] emission. Galaxy Evolution Explorer FUV imagery reveals a similar-sized, FUV-emitting shell. We determine a distance of 460 pc to AT Cnc, and an upper limit to its ejecta mass of {approx}5 Multiplication-Sign 10{sup -5} M {sub Sun }, typical of classical novae.

Torque-Controlled Adaptive Speed Control on a CNC Marble Saw Machine

Directory of Open Access Journals (Sweden)

Ugur Simsir

2015-02-01

Full Text Available Although CNC marble saw machines can automatically cut marble slabs to desired dimensions, saw speed and feed rate are selected by operator according to stone parameters, features of the saw, and its immersion depth. If the feed rate is selected lower than the optimal value, there will be time-loss and capacity deficiencies or if it is selected faster, cutting quality will decrease, spindle motor will draw more current, and saw blade will corrode faster. While cutting especially thick materials, saw may be stacked in the stone, cutting quality may be impaired, saw blade may be abraded earlier, precision quality may go down because of increase in measurement errors, and machine may be damaged with the increase in vibrations when improper feed rates are selected. Because of nonhomogeneity of the slabs and deterioration of the saw blade, operator cannot determine a persistent feed rate. This study is targeted to find saw speeds according to saw diameter and optimum feed rate by means of limiting vibrations and current drawn from saw motor and torque accordingly in order to increase working performance of CNC marble saw machines. Thanks to adaptive adjustment of feed rate, one can save on material as well as time, labour, and cost by making use of optimum energy.

GROUND-BASED TRANSIT OBSERVATIONS OF THE SUPER-EARTH 55 Cnc e

Energy Technology Data Exchange (ETDEWEB)

De Mooij, E. J. W. [Astronomy and Astrophysics, University of Toronto, Toronto (Canada); López-Morales, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA (United States); Karjalainen, R.; Hrudkova, M. [Isaac Newton Group of Telescopes, La Palma (Spain); Jayawardhana, Ray, E-mail: demooij@astro.utoronto.ca [Physics and Astronomy, York University, Toronto (Canada)

2014-12-20

We report the first ground-based detections of the shallow transit of the super-Earth exoplanet 55 Cnc e using a 2 m class telescope. Using differential spectrophotometry, we observed one transit in 2013 and another in 2014, with average spectral resolutions of ∼700 and ∼250, spanning the Johnson BVR photometric bands. We find a white light planet-to-star radius ratio of 0.0190{sub −0.0027}{sup +0.0023} from the 2013 observations and 0.0200{sub −0.0018}{sup +0.0017} from the 2014 observations. The two data sets combined result in a radius ratio of 0.0198{sub −0.0014}{sup +0.0013}. These values are all in agreement with previous space-based results. Scintillation noise in the data prevents us from placing strong constraints on the presence of an extended hydrogen-rich atmosphere. Nevertheless, our detections of 55 Cnc e in transit demonstrate that moderate-sized telescopes on the ground will be capable of routine follow-up observations of super-Earth candidates discovered by the Transiting Exoplanet Survey Satellite around bright stars. We expect it also will be possible to place constraints on the atmospheric characteristics of those planets by devising observational strategies to minimize scintillation noise.

Novel hydrophilic nanostructured microtexture on direct metal laser sintered Ti-6Al-4V surfaces enhances osteoblast response in vitro and osseointegration in a rabbit model.

Science.gov (United States)

Hyzy, Sharon L; Cheng, Alice; Cohen, David J; Yatzkaier, Gustavo; Whitehead, Alexander J; Clohessy, Ryan M; Gittens, Rolando A; Boyan, Barbara D; Schwartz, Zvi

2016-08-01

The purpose of this study was to compare the biological effects in vivo of hierarchical surface roughness on laser sintered titanium-aluminum-vanadium (Ti-6Al-4V) implants to those of conventionally machined implants on osteoblast response in vitro and osseointegration. Laser sintered disks were fabricated to have micro-/nano-roughness and wettability. Control disks were computer numerical control (CNC) milled and then polished to be smooth (CNC-M). Laser sintered disks were polished smooth (LST-M), grit blasted (LST-B), or blasted and acid etched (LST-BE). LST-BE implants or implants manufactured by CNC milling and grit blasted (CNC-B) were implanted in the femurs of male New Zealand white rabbits. Most osteoblast differentiation markers and local factors were enhanced on rough LST-B and LST-BE surfaces in comparison to smooth CNC-M or LST-M surfaces for MG63 and normal human osteoblast cells. To determine if LST-BE implants were osteogenic in vivo, we compared them to implant surfaces used clinically. LST-BE implants had a unique surface with combined micro-/nano-roughness and higher wettability than conventional CNC-B implants. Histomorphometric analysis demonstrated a significant improvement in cortical bone-implant contact of LST-BE implants compared to CNC-B implants after 3 and 6 weeks. However, mechanical testing revealed no differences between implant pullout forces at those time points. LST surfaces enhanced osteoblast differentiation and production of local factors in vitro and improved the osseointegration process in vivo. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2086-2098, 2016. © 2016 Wiley Periodicals, Inc.

Application of the Taguchi technique for the optimization of surface roughness and tool life during the milling of Hastelloy C22

International Nuclear Information System (INIS)

Kivak, Turgay; Mert, Senol

2017-01-01

In this study, the effects of machining parameters on surface roughness (Ra) and tool life (Tl) were investigated in the milling of Hastelloy C22 alloy with TiAlN-coated carbide inserts. A number of milling experiments were conducted using the L_2_7 (3"3) Taguchi orthogonal array on a CNC milling machine under different cutting conditions (dry, compressed air and wet). The cutting condition, cutting speed and feed rate were determined as the essential machining parameters. Analysis of variance (ANOVA) and signal-to-noise (S/N) ratio were employed to evaluate the effects of the machining parameters on Ra and Tl, and prediction models were created using quadratic regression analyses. The results revealed that the feed rate and cutting condition were the most influential factors on surface roughness and flank wear. The maximum tool life was achieved under wet cutting condition using a cutting speed of 30 x min"-"1 and a feed rate of 0.08 mm x rev"-"1, while the minimum surface roughness value was obtained under wet cutting condition using a cutting speed of 50 m x min"-"1 and the same feed rate. Using the optimum cutting parameters for Tl (30 m x min"-"1, 0.08 mm x rev"-"1), increases of 234 % and 67 % in tool life were observed under wet and compressed air cutting conditions, respectively, compared to the dry cutting condition.

Application of the Taguchi technique for the optimization of surface roughness and tool life during the milling of Hastelloy C22

Energy Technology Data Exchange (ETDEWEB)

Kivak, Turgay; Mert, Senol [Duezce Univ. (Turkey). Dept. of Manufacturing Engineering

2017-02-01

In this study, the effects of machining parameters on surface roughness (Ra) and tool life (Tl) were investigated in the milling of Hastelloy C22 alloy with TiAlN-coated carbide inserts. A number of milling experiments were conducted using the L{sub 27} (3{sup 3}) Taguchi orthogonal array on a CNC milling machine under different cutting conditions (dry, compressed air and wet). The cutting condition, cutting speed and feed rate were determined as the essential machining parameters. Analysis of variance (ANOVA) and signal-to-noise (S/N) ratio were employed to evaluate the effects of the machining parameters on Ra and Tl, and prediction models were created using quadratic regression analyses. The results revealed that the feed rate and cutting condition were the most influential factors on surface roughness and flank wear. The maximum tool life was achieved under wet cutting condition using a cutting speed of 30 x min{sup -1} and a feed rate of 0.08 mm x rev{sup -1}, while the minimum surface roughness value was obtained under wet cutting condition using a cutting speed of 50 m x min{sup -1} and the same feed rate. Using the optimum cutting parameters for Tl (30 m x min{sup -1}, 0.08 mm x rev{sup -1}), increases of 234 % and 67 % in tool life were observed under wet and compressed air cutting conditions, respectively, compared to the dry cutting condition.

Tutorial Continuing Education: Innovative Strategy in a Tertiary Specialized Health Unit

Directory of Open Access Journals (Sweden)

Flaviana Maciel

2017-06-01

Full Text Available Hospital Pelopidas Silveira-IMIP/SES/SUS is a tertiary-unit, specialized in cardiology, neurology, neurosurgery and interventional radiology. It is the only hospital of Brazilian Public-Health-System (SUS with this profile and a 24h-acute-cardio/neurovascular facility. Challenges of Continuing-Education include a guaranteeing appropriate level of basic knowledge, b empowering clinical staff to remain up to date in current knowledge. HPS Continuing-Education Program is based on three branches: a Classroom-Tutorials (CT, b Online-Tutorials at "Pelopidas Digital" Virtual-Teaching-Platform (PD-VTP and c Daily-Practice Evaluation (DPE. This paper presents logistic details of HPS Continuing-Education Program. Training team coordinates tutorial meetings and performs continuous statistical analysis. Evaluation team visit hospital departments daily, observing in practice the incorporation of information provided, and retraining individuals in their work scenarios. Both teams perform curriculum development, meeting planning and creation of digital-training-modules. Tutorial meetings have pre/post-tests, allowing monitoring of attendance, topic significance and short-term retention. Tutorial groups are formed by 6-12 employees sharing similarities in training needs. CT is offered to 4 groups-of-interest: a nurses, b nursing assistants, c administrative staff, porters, drivers, d cleaning, laundry and security staff. Problematization and active strategies have resulted into an attractive, structured educational program customized to produce short-term results. The strategy is of interest to institutions sharing similar challenges.

Tutorial on X-ray photon counting detector characterization.

Science.gov (United States)

Ren, Liqiang; Zheng, Bin; Liu, Hong

2018-01-01

Recent advances in photon counting detection technology have led to significant research interest in X-ray imaging. As a tutorial level review, this paper covers a wide range of aspects related to X-ray photon counting detector characterization. The tutorial begins with a detailed description of the working principle and operating modes of a pixelated X-ray photon counting detector with basic architecture and detection mechanism. Currently available methods and techniques for charactering major aspects including energy response, noise floor, energy resolution, count rate performance (detector efficiency), and charge sharing effect of photon counting detectors are comprehensively reviewed. Other characterization aspects such as point spread function (PSF), line spread function (LSF), contrast transfer function (CTF), modulation transfer function (MTF), noise power spectrum (NPS), detective quantum efficiency (DQE), bias voltage, radiation damage, and polarization effect are also remarked. A cadmium telluride (CdTe) pixelated photon counting detector is employed for part of the characterization demonstration and the results are presented. This review can serve as a tutorial for X-ray imaging researchers and investigators to understand, operate, characterize, and optimize photon counting detectors for a variety of applications.

An interactive tutorial on radiation protection for medical students

International Nuclear Information System (INIS)

Sendra-Portero, F.; Martinez-Morillo, M.

2003-01-01

The aim of this project is to develop an interactive tutorial designed for medical students training in radiation protection in order to use its definitive version in a collaborative group of medical schools. The contents of the tutorial matchers the outlines proposed by the EC guidelines on education and training in Radiation Protection for Medical exposures (RP118), for medical and dental schools. The tutorial is organised in virtual lectures, following a similar structure than the traditional lectures, slides and explanations. There is a central script for each theme with a forward-return interaction. Additionally, branches with deeper explanations (drawings, images, videos,...) are provided to the user. The tutorial is being developed on a set of power Point presentations, linked between them. The user can choose two ways sto launch each lecture, based either on spoken (audio) or written explanations. We present the initial version of a useful tool for pre-graduate training of general practitioners in Radiation Protection, which is a complementary tool for personally adapted computed-based education. Most of the contents can be easily adapted for other students of health related careers (i. e. nurses, technologists...) The use of multimedia tools has been recommended in the field of radiation protection, but developing these tools is time consuming and needs expertise in both, educative and multimedia resources. This projects takes part of more than a dozen multimedia projects on different radiology related subjects developed in our department. (Author) 6 refs

Step-and-Repeat Nanoimprint-, Photo- and Laser Lithography from One Customised CNC Machine.

Science.gov (United States)

Greer, Andrew Im; Della-Rosa, Benoit; Khokhar, Ali Z; Gadegaard, Nikolaj

2016-12-01

The conversion of a computer numerical control machine into a nanoimprint step-and-repeat tool with additional laser- and photolithography capacity is documented here. All three processes, each demonstrated on a variety of photoresists, are performed successfully and analysed so as to enable the reader to relate their known lithography process(es) to the findings. Using the converted tool, 1 cm(2) of nanopattern may be exposed in 6 s, over 3300 times faster than the electron beam equivalent. Nanoimprint tools are commercially available, but these can cost around 1000 times more than this customised computer numerical control (CNC) machine. The converted equipment facilitates rapid production and large area micro- and nanoscale research on small grants, ultimately enabling faster and more diverse growth in this field of science. In comparison to commercial tools, this converted CNC also boasts capacity to handle larger substrates, temperature control and active force control, up to ten times more curing dose and compactness. Actual devices are fabricated using the machine including an expanded nanotopographic array and microfluidic PDMS Y-channel mixers.

Adaptive Tutorials Versus Web-Based Resources in Radiology: A Mixed Methods Comparison of Efficacy and Student Engagement.

Science.gov (United States)

Wong, Vincent; Smith, Ariella J; Hawkins, Nicholas J; Kumar, Rakesh K; Young, Noel; Kyaw, Merribel; Velan, Gary M

2015-10-01

Diagnostic imaging is under-represented in medical curricula globally. Adaptive tutorials, online intelligent tutoring systems that provide a personalized learning experience, have the potential to bridge this gap. However, there is limited evidence of their effectiveness for learning about diagnostic imaging. We performed a randomized mixed methods crossover trial to determine the impact of adaptive tutorials on perceived engagement and understanding of the appropriate use and interpretation of common diagnostic imaging investigations. Although concurrently engaged in disparate blocks of study, 99 volunteer medical students (from years 1-4 of the 6-year program) were randomly allocated to one of two groups. In the first arm of the trial on chest X-rays, one group received access to an adaptive tutorial, whereas the other received links to an existing peer-reviewed Web resource. These two groups crossed over in the second arm of the trial, which focused on computed tomography scans of the head, chest, and abdomen. At the conclusion of each arm of the trial, both groups completed an examination-style assessment, comprising questions both related and unrelated to the topics covered by the relevant adaptive tutorial. Online questionnaires were used to evaluate student perceptions of both learning resources. In both arms of the trial, the group using adaptive tutorials obtained significantly higher assessment scores than controls. This was because of higher assessment scores by senior students in the adaptive tutorial group when answering questions related to topics covered in those tutorials. Furthermore, students indicated significantly better engagement with adaptive tutorials than the Web resource and rated the tutorials as a significantly more valuable tool for learning. Medical students overwhelmingly accept adaptive tutorials for diagnostic imaging. The tutorials significantly improve the understanding of diagnostic imaging by senior students. Crown Copyright �

Spectroscopic investigation of the Hg-Mn star κ Cnc. I. Choice of parameters of the model atmosphere and determination of the helium abundance

International Nuclear Information System (INIS)

Dobrichev, V.M.; Raikova, D.V.; Ryabchikova, T.A.; Topil'skaya, G.P.

1989-01-01

It is shown that a blanketed model atmosphere of the Hg-Mn star κ Cnc with T e = 12,800 degree K and log g = 3.7 (Stepien and Muthsam) completely describes the profiles of the lines H α , H γ , and H δ in the spectrum of this star. The synthetic-spectrum method is used to determine the helium abundance in the atmosphere of κ Cnc: He/H = 0.017, this value being almost three times greater than the value obtained earlier for this star by Adelman. The isotope shift of the lines leads to the isotope ratio 3 He/ 4 He = 0.35, and this indicates that there is a process of diffusion separation of the elements in the atmosphere of κ Cnc. 23 refs., 3 figs., 1 tab

Tool path in torus tool CNC machining

Directory of Open Access Journals (Sweden)

XU Ying

2016-10-01

Full Text Available This paper is about tool path in torus tool CNC machining.The mathematical model of torus tool is established.The tool path planning algorithm is determined through calculation of the cutter location,boundary discretization,calculation of adjacent tool path and so on,according to the conversion formula,the cutter contact point will be converted to the cutter location point and then these points fit a toolpath.Lastly,the path planning algorithm is implemented by using Matlab programming.The cutter location points for torus tool are calculated by Matlab,and then fit these points to a toolpath.While using UG software,another tool path of free surface is simulated of the same data.It is drew compared the two tool paths that using torus tool is more efficient.

An Online Tutorial vs. Pre-Recorded Lecture for Reducing Incidents of Plagiarism

Science.gov (United States)

Henslee, Amber M.; Goldsmith, Jacob; Stone, Nancy J.; Krueger, Merilee

2015-01-01

The current study compared an online academic integrity tutorial modified from Belter & du Pre (2009) to a pre-recorded online academic integrity lecture in reducing incidents of plagiarism among undergraduate students at a science and technology university. Participants were randomized to complete either the tutorial or the pre-recorded…

Psychosemiotics and Libraries: Identifying Signways in Library Informational Guides, Games, and Tutorials

Science.gov (United States)

Laster, Barbara; Blummer, Barbara; Kenton, Jeffrey M.

2010-01-01

Tutorials and digital learning objects provide librarians a quick, concise mechanism for delivering information and training on a wide range of library topics. The semiotic theory promoted by Charles Sanders Peirce (Wiener, 1958) and Howard Smith (2005) contains implications for enhancing the effectiveness of library tutorials through the…

Transcript for Understanding Medical Words: A Tutorial

Science.gov (United States)

... medlineplus.gov/medicalwordstranscript.html Transcript for Understanding Medical Words: A Tutorial To use the sharing features on ... get to what those mean in a minute. Word Roots Word Roots. Let's begin with body parts. ...

Indico CONFERENCE tutorial

CERN Multimedia

CERN. Geneva; Manzoni, Alex Marc

2017-01-01

This short tutorial explains how to create a CONFERENCE in indico and how to handle abstracts and registration forms, in detail: Timestamps: 1:01 - Programme  2:28 - Call for abstracts  11:50 - Abstract submission  13:41 - Abstract Review 15:41 - The Judge's Role 17:23 - Registration forms' creation 23:34 - Candidate participant's registration/application 25:54 - Customisation of Indico pages - Layout 28:08 - Customisation of Indico pages - Menus 29:47 - Configuring Event reminders and import into calendaring tools   See HERE a recent presentation by Pedro about the above steps in the life of an indico CONFERENCE event.

Solar Tutorial and Annotation Resource (STAR)

Science.gov (United States)

Showalter, C.; Rex, R.; Hurlburt, N. E.; Zita, E. J.

2009-12-01

We have written a software suite designed to facilitate solar data analysis by scientists, students, and the public, anticipating enormous datasets from future instruments. Our “STAR" suite includes an interactive learning section explaining 15 classes of solar events. Users learn software tools that exploit humans’ superior ability (over computers) to identify many events. Annotation tools include time slice generation to quantify loop oscillations, the interpolation of event shapes using natural cubic splines (for loops, sigmoids, and filaments) and closed cubic splines (for coronal holes). Learning these tools in an environment where examples are provided prepares new users to comfortably utilize annotation software with new data. Upon completion of our tutorial, users are presented with media of various solar events and asked to identify and annotate the images, to test their mastery of the system. Goals of the project include public input into the data analysis of very large datasets from future solar satellites, and increased public interest and knowledge about the Sun. In 2010, the Solar Dynamics Observatory (SDO) will be launched into orbit. SDO’s advancements in solar telescope technology will generate a terabyte per day of high-quality data, requiring innovation in data management. While major projects develop automated feature recognition software, so that computers can complete much of the initial event tagging and analysis, still, that software cannot annotate features such as sigmoids, coronal magnetic loops, coronal dimming, etc., due to large amounts of data concentrated in relatively small areas. Previously, solar physicists manually annotated these features, but with the imminent influx of data it is unrealistic to expect specialized researchers to examine every image that computers cannot fully process. A new approach is needed to efficiently process these data. Providing analysis tools and data access to students and the public have proven

Comparative evaluation of laser-assisted micro-milling for AISI 316, AISI 422, TI-6AL-4V and Inconel 718 in a side-cutting configuration

International Nuclear Information System (INIS)

Shelton, Jonathan A; Shin, Yung C

2010-01-01

This paper is focused on numerical modeling and experimental evaluation of laser-assisted micro-milling (LAMM). An experimental setup consisting of a 25 W CO 2 laser, three-axis CNC linear stages and a high-speed spindle was used to implement the LAMM process. Micro-endmills between 100 and 300 µm in diameter were used to perform side-cutting operations with and without laser preheat on four materials: AISI 316, AISI 422, Ti-6Al-4V and Inconel 718. A three-dimensional transient finite-volume-based thermal model was used to analytically predict appropriate process parameters on the basis of material-removal temperatures. The effects of LAMM on the machined surface finish, edge burrs, tool wear and workpiece microstructure were evaluated experimentally.

Assimilation of contents and learning through the use of video tutorials

Directory of Open Access Journals (Sweden)

David JIMÉNEZ CASTILLO

2013-01-01

Full Text Available The need for a change in the university educational model promoted by the establishment of the European Higher Education Area (EHEA has promoted the implementation of numerous proposals for innovation in university teaching. These innovative practices that are based on a process of reflection and analysis of past teaching experience, are helping to improve qualitatively the teaching practice and, consequently, the learning process and outcomes of students, from a process of reflection and analysis of the teaching experience. In this context, this paper focuses on analyzing a specific teaching tool for innovation, the video tutorial, in order to assess its influence on the processes of assimilation of contents and self-learning. In particular, we attempt to show if the video tutorial allows reinforcing the understanding of practical contents that have been previously given by the classical method of masterly exposition. From the analysis of data obtained through a survey directed to a sample of students after experimenting with the teaching tool, it is shown that the video tutorial is considered a very suitable tool to improve the assimilation capacity of the contents taught previously and to acquire higher learning. After performing a regression analysis, the research also shows that students’ attitudes toward multimedia tools and the perceived utility of video tutorial positively influence these capacities. On the contrary, we find that the attitude towards individual learning and the attention paid by the student to the contents of the video tutorial do not affect the level of learning obtained from this tool.

LCA Study for Pilot Scale Production of Cellulose Nano Crystals (CNC) from Wood Pulp

Science.gov (United States)

Hongmei Gu; Richard Reiner; Richard Bergman; Alan Rudie

2015-01-01

Interest in cellulose nanocrystals (CNC)/cellulose nanofibrils (CNF) made from woody biomass has been growing rapidly with close attention from pulp and paper industry, governments, universities, and research institutes. Many new products development with CNCs have been studied intensively. However, little life-cycle analysis (LCA) has been conducted for the...

Chapter 1.4: Spatially Resolved Characterization of CNC-Polypropylene composite by Confocal Raman Microscopy

Science.gov (United States)

Umesh Agarwal; Ronald Sabo; Richard Reiner; Craig Clemons; Alan Rudie

2013-01-01

Raman spectroscopy was used to analyze cellulose nanocrystal (CNC)-polypropylene (PP) composites and to investigate the spatial distribution of CNCs in extruded composite filaments. Three composites were made from two forms of nanocellulose (CNCs from wood pulp and the nanoscale fraction of microcrystalline cellulose), and two of the three composites...

RADIAL VELOCITY PLANETS DE-ALIASED: A NEW, SHORT PERIOD FOR SUPER-EARTH 55 Cnc e

International Nuclear Information System (INIS)

Dawson, Rebekah I.; Fabrycky, Daniel C.

2010-01-01

Radial velocity measurements of stellar reflex motion have revealed many extrasolar planets, but gaps in the observations produce aliases, spurious frequencies that are frequently confused with the planets' orbital frequencies. In the case of Gl 581 d, the distinction between an alias and the true frequency was the distinction between a frozen, dead planet and a planet possibly hospitable to life. To improve the characterization of planetary systems, we describe how aliases originate and present a new approach for distinguishing between orbital frequencies and their aliases. Our approach harnesses features in the spectral window function to compare the amplitude and phase of predicted aliases with peaks present in the data. We apply it to confirm prior alias distinctions for the planets GJ 876 d and HD 75898 b. We find that the true periods of Gl 581 d and HD 73526 b/c remain ambiguous. We revise the periods of HD 156668 b and 55 Cnc e, which were afflicted by daily aliases. For HD 156668 b, the correct period is 1.2699 days and the minimum mass is (3.1 ± 0.4) M + . For 55 Cnc e, the correct period is 0.7365 days-the shortest of any known planet-and the minimum mass is (8.3 ± 0.3) M + . This revision produces a significantly improved five-planet Keplerian fit for 55 Cnc, and a self-consistent dynamical fit describes the data just as well. As radial velocity techniques push to ever-smaller planets, often found in systems of multiple planets, distinguishing true periods from aliases will become increasingly important.

Machine Shop Facilities

Data.gov (United States)

Federal Laboratory Consortium — Projects at IARC can benefit from Fermilab's experienced machinists, welders, and extensive on-site equipment. Equipment includes conventional and CNC mills, lathes,...

Tutorial: Digital microfluidic biochips: Towards hardware/software co-design and cyber-physical system integration

DEFF Research Database (Denmark)

Ho, Tsung-Yi; Huang, Juinn-Dar; Pop, Paul

2013-01-01

This tutorial will first provide an overview of typical bio-molecular applications (market drivers) such as immunoassays, DNA sequencing, clinical chemistry, etc. Next, microarrays and various microfluidic platforms will be discussed. The next part of the tutorial will focus on electro-wetting-ba......This tutorial will first provide an overview of typical bio-molecular applications (market drivers) such as immunoassays, DNA sequencing, clinical chemistry, etc. Next, microarrays and various microfluidic platforms will be discussed. The next part of the tutorial will focus on electro......-wetting-based digital micro-fluidic biochips. The key idea here is to manipulate liquids as discrete droplets. A number of case studies based on representative assays and laboratory procedures will be interspersed in appropriate places throughout the tutorial. Basic concepts in micro-fabrication techniques will also...... be discussed. Attendees will next learn about CAD and reconfiguration aspects of digital microfluidic biochips. Synthesis tools will be described to map assay protocols from the lab bench to a droplet-based microfluidic platform and generate an optimized schedule of bioassay operations, the binding of assay...

Hydrogenation of imines catalysed by ruthenium(II) complexes based on lutidine-derived CNC pincer ligands.

Science.gov (United States)

Hernández-Juárez, Martín; Vaquero, Mónica; Álvarez, Eleuterio; Salazar, Verónica; Suárez, Andrés

2013-01-14

The preparation of new Ru(II) complexes incorporating fac-coordinated lutidine-derived CNC ligands is reported. These derivatives are selectively deprotonated by (t)BuOK at one of the methylene arms of the pincer, leading to catalytically active species in the hydrogenation of imines.

From DIY tutorials to DIY recipes

NARCIS (Netherlands)

Dalton, M.; Desjardins, A.; Wakkary, R.L.

2014-01-01

While online DIY (do-it-yourself) tutorials have increasingly gained interest both at CHI and in the DIY and Maker communities, there is not a lot of research concerning the qualities and drawbacks of the current formats used to share DIY knowledge online. Drawing on our current study of DIY

The Web Lecture Archive Project: Archiving ATLAS Presentations and Tutorials

CERN Multimedia

Herr, J

2004-01-01

The geographical diversity of the ATLAS Collaboration presents constant challenges in the communication between and training of its members. One important example is the need for training of new collaboration members and/or current members on new developments. The Web Lecture Archive Project (WLAP), a joint project between the University of Michigan and CERN Technical Training, has addressed this challenge by recording ATLAS tutorials in the form of streamed "Web Lectures," consisting of synchronized audio, video and high-resolution slides, available on demand to anyone in the world with a Web browser. ATLAS software tutorials recorded by WLAP include ATHENA, ATLANTIS, Monte Carlo event generators, Object Oriented Analysis and Design, GEANT4, and Physics EDM and tools. All ATLAS talks, including both tutorials and meetings are available at http://www.wlap.org/browser.php?ID=atlas. Members of the University of Michigan Physics Department and Media Union, under the framework of the ATLAS Collaboratory Project ...

Mechanical alloying and reactive milling in a high energy planetary mill

International Nuclear Information System (INIS)

Jiang Xianjin; Trunov, Mikhaylo A.; Schoenitz, Mirko; Dave, Rajesh N.; Dreizin, Edward L.

2009-01-01

Powder refinement in a planetary mill (Retsch PM 400-MA) is investigated experimentally and analyzed using discrete element modeling (DEM). Refinement is defined as the average size of the individual components in a composite powder. The specific milling dose, defined as the product of charge ratio and milling time, is used as an experimental parameter tracking the progress of the material refinement. This parameter is determined experimentally for milling of boron and titanium powders, for which the time of initiation of a self-sustained reaction is measured under different milling conditions. It is assumed that the reaction becomes self-sustaining when the same powder refinement is achieved. The DEM calculations established that the milling balls primarily roll along the milling container's perimeter. The inverse of the rate of energy dissipation resulting from this rolling motion is used as the DEM analog of the specific milling dose. The results correlate well with experimental observations.

SFO-Project: The New Generation of Sharable, Editable and Open-Access CFD Tutorials

Science.gov (United States)

Javaherchi, Teymour; Javaherchi, Ardeshir; Aliseda, Alberto

2016-11-01

One of the most common approaches to develop a Computational Fluid Dynamic (CFD) simulation for a new case study of interest is to search for the most similar, previously developed and validated CFD simulation among other works. A simple search would result into a pool of written/visual tutorials. However, users should spend significant amount of time and effort to find the most correct, compatible and valid tutorial in this pool and further modify it toward their simulation of interest. SFO is an open-source project with the core idea of saving the above-mentioned time and effort. This is done via documenting/sharing scientific and methodological approaches to develop CFD simulations for a wide spectrum of fundamental and industrial case studies in three different CFD solvers; STAR-CCM +, FLUENT and Open FOAM (SFO). All of the steps and required files of these tutorials are accessible and editable under the common roof of Github (a web-based Git repository hosting service). In this presentation we will present the current library of 20 + developed CFD tutorials, discuss the idea and benefit of using them, their educational values and explain how the next generation of open-access and live resource of CFD tutorials can be built further hand-in-hand within our community.

Educational Tutorial Video with Aspects of Psychological Sensation and Perception in Academic Achievement

Directory of Open Access Journals (Sweden)

Martha Jiménez García

2015-09-01

Full Text Available In Mexico 75.5% of children and young students in elementary and secondary school are at insufficient and elementary levels in mathematics. The purpose of this research is to join the UNESCO initiative by granting quality education, boosted by technology (Rose, 2013. Specifically, the objective is to analyze the impact of using a tutorial video on academic achievement, based on Gestalt psychology stimulating the sensation and perception cognitive capabilities. Using a 50 student sample was used, which was divided into two groups (experimental and control we test whether students that use a tutorial video based on sensation and perception increase their attention and interest to increase academic achievement. The experimental group was a virtual class with tutorial videos on the use of slopes, explanation of the equation, and a virtual graph generator. Both groups were a survey and an exam. The results show that a high impact on the grades and on the perception of knowledge in the experimental group; the average academic achievement of the experimental group was 9.31, against 2 in the control group. Thus, we conclude that the tutorial video presented stimulates cognitive capabilities and improves academic achievement with a 7.3 impact per additional unit of tutorial video, presented as reinforcement of the class.

Tutorials in endovascular neurosurgery and interventional neuroradiology

International Nuclear Information System (INIS)

Byrne, James Vincent

2012-01-01

This book aims to provide the trainee and practicing minimally invasive neurological therapist with a comprehensive understanding of the background science and theory that forms the foundation of their work. The contents are based on the tutorial teaching techniques used at the University of Oxford and are authored by the MSc Course Director. The tutorial is a learning episode focussed on a particular topic and intended to guide the student/reader through the background literature, to highlight the research on which standard practices are based and to provide the insights of an experienced practitioner. Each chapter of the book covers a different topic to build a complete review of the subspecialty, with in-depth discussion of all currently used techniques. The literature is reviewed and presented in context to illustrate its importance to the practice of this rapidly expanding field of medical treatment.

Tutorials in endovascular neurosurgery and interventional neuroradiology

Energy Technology Data Exchange (ETDEWEB)

Byrne, James Vincent [Univ. of Oxford, Oxford (United Kingdom). Dept. of Neuroradiology

2012-07-01

This book aims to provide the trainee and practicing minimally invasive neurological therapist with a comprehensive understanding of the background science and theory that forms the foundation of their work. The contents are based on the tutorial teaching techniques used at the University of Oxford and are authored by the MSc Course Director. The tutorial is a learning episode focussed on a particular topic and intended to guide the student/reader through the background literature, to highlight the research on which standard practices are based and to provide the insights of an experienced practitioner. Each chapter of the book covers a different topic to build a complete review of the subspecialty, with in-depth discussion of all currently used techniques. The literature is reviewed and presented in context to illustrate its importance to the practice of this rapidly expanding field of medical treatment.

DEVELOPMENT OF A CNC MICRO-LATHE FOR BONE MICROIMPLANTS DESARROLLO DE UN MICROTORNO CNC PARA MICROIMPLANTES DE HUESO DESENVOLVIMENTO DE UM MICROTORNO CNC PARA MICROIMPLANTES DE OSSO

Directory of Open Access Journals (Sweden)

Daniel A. Rangel

2011-06-01

Full Text Available This paper evaluates the development of a CNC micro-lathe concept, continuing with the research in the development of machine tool prototypes by LATEMM. A micromachining center developed in 2004-2005 at Universidad de los Andes was studied, and based on the results obtained, a new prototype was proposed. The motivation behind the design and construction of this machine tool was to achieve higher precision in the machining process compared with conventional turning produced in macro machine tools. A machine, with spindle rotation speed up to 300 000 rpm was achieved, the cutting tool moves in two axes through step motors connected to worm gear reductions, thus resolution of 1µm is achieved. The interpolator was programmed based on DDA integration. The machine was set under a stereoscope to visualize the machining operations with zoom up to 30X. Micromachining was reached adopting NC control and it was possible to characterize micro-turned cortical bone samples.Este artículo evalúa el desarrollo de un concepto de microtorno CNC, siguiendo la línea de investigación en el desarrollo de prototipos de máquinas-herramientas por parte del LATEMM. Se estudió un centro de micromecanizado desarrollado en 2004-2005 en la Universidad de los Andes y con base en los resultados obtenidos se propuso un nuevo prototipo. La motivación detrás del diseño y la construcción de esta micromáquina herramienta era alcanzar mayor precisión en el mecanizado en comparación con el torneado convencional producido en máquinas-herramientas de tamaño macro. Se logró una máquina que alcanzó una velocidad de rotación de hasta 300.000 rpm en el husillo, la herramienta de corte se mueve en dos ejes a través de motores de paso conectados a sistemas de reducción sinfín-corona con lo que se logra una resolución de 1µm, además se programó interpolación basada en integración DDA. La máquina fue montada bajo un estereoscopio para visualizar las operaciones de

Design and Analysis of simulation experiments : Tutorial

NARCIS (Netherlands)

Kleijnen, J.P.C.

2017-01-01

This tutorial reviews the design and analysis of simulation experiments. These experiments may have various goals: validation, prediction, sensitivity analysis, optimization (possibly robust), and risk or uncertainty analysis. These goals may be realized through metamodels. Two types of metamodels

Site-Selective Modification of Cellulose Nanocrystals with Isophorone Diisocyanate and Formation of Polyurethane-CNC Composites.

Science.gov (United States)

Girouard, Natalie M; Xu, Shanhong; Schueneman, Gregory T; Shofner, Meisha L; Meredith, J Carson

2016-01-20

The unequal reactivity of the two isocyanate groups in an isophorone diisocyante (IPDI) monomer was exploited to yield modified cellulose nanocrystals (CNCs) with both urethane and isocyanate functionality. The chemical functionality of the modified CNCs was verified with ATR-FTIR analysis and elemental analysis. The selectivity for the secondary isocyanate group using dibutyl tin dilaurate (DBTDL) as the reaction catalyst was confirmed with (13)C NMR. The modified CNCs showed improvements in the onset of thermal degradation by 35 °C compared to the unmodified CNCs. Polyurethane composites based on IPDI and a trifunctional polyether alcohol were synthesized using unmodified (um-CNC) and modified CNCs (m-CNC). The degree of nanoparticle dispersion was qualitatively assessed with polarized optical microscopy. It was found that the modification step facilitated superior nanoparticle dispersion compared to the um-CNCs, which resulted in increases in the tensile strength and work of fracture of over 200% compared to the neat matrix without degradation of elongation at break.

A Pilot Evaluation of a Tutorial to Teach Clients and Clinicians About Gambling Game Design.

Science.gov (United States)

Turner, Nigel E; Robinson, Janine; Harrigan, Kevin; Ferentzy, Peter; Jindani, Farah

2018-01-01

This paper describes the pilot evaluation of an Internet-based intervention, designed to teach counselors and problem gamblers about how electronic gambling machines (EGMs) work. This study evaluated the tutorial using assessment tools, such as rating scales and test of knowledge about EGMs and random chance. The study results are based on a number of samples, including problem gambling counselors ( n  = 25) and problem gamblers ( n  = 26). The interactive tutorial was positively rated by both clients and counselors. In addition, we found a significant improvement in scores on a content test about EGM games for both clients and counselors. An analysis of the specific items suggests that the effects of the tutorial were mainly on those items that were most directly related to the content of the tutorial and did not always generalize to other items. This tutorial is available for use with clients and for education counselors. The data also suggest that the tutorial is equally effective in group settings and in individual settings. These results are promising and illustrate that the tool can be used to teach counselors and clients about game design. Furthermore, research is needed to evaluate its impact on gambling behavior.

Design and accuracy analysis of a metamorphic CNC flame cutting machine for ship manufacturing

Science.gov (United States)

Hu, Shenghai; Zhang, Manhui; Zhang, Baoping; Chen, Xi; Yu, Wei

2016-09-01

The current research of processing large size fabrication holes on complex spatial curved surface mainly focuses on the CNC flame cutting machines design for ship hull of ship manufacturing. However, the existing machines cannot meet the continuous cutting requirements with variable pass conditions through their fixed configuration, and cannot realize high-precision processing as the accuracy theory is not studied adequately. This paper deals with structure design and accuracy prediction technology of novel machine tools for solving the problem of continuous and high-precision cutting. The needed variable trajectory and variable pose kinematic characteristics of non-contact cutting tool are figured out and a metamorphic CNC flame cutting machine designed through metamorphic principle is presented. To analyze kinematic accuracy of the machine, models of joint clearances, manufacturing tolerances and errors in the input variables and error models considering the combined effects are derived based on screw theory after establishing ideal kinematic models. Numerical simulations, processing experiment and trajectory tracking experiment are conducted relative to an eccentric hole with bevels on cylindrical surface respectively. The results of cutting pass contour and kinematic error interval which the position error is from-0.975 mm to +0.628 mm and orientation error is from-0.01 rad to +0.01 rad indicate that the developed machine can complete cutting process continuously and effectively, and the established kinematic error models are effective although the interval is within a `large' range. It also shows the matching property between metamorphic principle and variable working tasks, and the mapping correlation between original designing parameters and kinematic errors of machines. This research develops a metamorphic CNC flame cutting machine and establishes kinematic error models for accuracy analysis of machine tools.

Interaction Patterns in Synchronous Chinese Tutorials

Science.gov (United States)

Shi, Lijing; Stickler, Ursula

2018-01-01

Speaking in Chinese is problematic for all learners, particularly for beginners and more so during online interaction. Despite the fact that interaction has been identified as crucial for the development of speaking skills, it can be hindered by students' lack of language competence or their anxiety. Teacher-centred practices in tutorials can…

Basic CNC Operation. Training Workbook [and] Assessment and Training Guide [and] Hands-on Assessment.

Science.gov (United States)

Anoka-Hennepin Technical Coll., Minneapolis, MN.

This workbook is intended for students taking a course in basic computer numerical control (CNC) operation that was developed during a project to retrain defense industry workers at risk of job loss or dislocation because of conversion of the defense industry. The workbook contains daily training guides for each of the course's 13 sessions. Among…

Learning Control: Sense-Making, CNC Machines, and Changes in Vocational Training for Industrial Work

Science.gov (United States)

Berner, Boel

2009-01-01

The paper explores how novices in school-based vocational training make sense of computerized numerical control (CNC) machines. Based on two ethnographic studies in Swedish schools, one from the early 1980s and one from 2006, it analyses change and continuity in the cognitive, social, and emotional processes of learning how to become a machine…

CNC Turning Center Operations and Prove Out. Computer Numerical Control Operator/Programmer. 444-334.

Science.gov (United States)

Skowronski, Steven D.

This student guide provides materials for a course designed to instruct the student in the recommended procedures used when setting up tooling and verifying part programs for a two-axis computer numerical control (CNC) turning center. The course consists of seven units. Unit 1 discusses course content and reviews and demonstrates set-up procedures…

Research on the Influence of Cutting Rates on Macrogeometry Deflections of Surfaces under Processing Complex form Products Made of Aluminium Aloys

Directory of Open Access Journals (Sweden)

Ieva Švagždytė

2015-03-01

Full Text Available The article reviews the influence of cutting rates on macrogeometry deflection of milling complex form products and turning an outside surface. For that purpose, one of the most popular aluminium alloys 6082 has been chosen. A ball nose mill of 8 mm in diameter has been milled employing CNC vertical centre HAAS MINI MILL and applying CNC lathe HAAS ST 20 for turning. Measurements have been carried out using coordinate measuring machine DEA micro-hite DCC, applying the probe sphere of 3mm in diameter and the probe equipped with a needle. A deviation of the surface profile from tangent to therophore parabola has been investigated. The determinants R2 of the obtained regressive equation have disclosed that the depth of the cut has the biggest influence on macrogeometry deflections, whereas feed rate has a slighter influence and cutting speed has no radical influence. For the turning process, the depth of the cut has the strongest influence on circularity while cilindrisity has been mainly affected by cutting speed.

Interactive Intragroup Tutorials: A Need-Based Modification to Enhance Learning in Physiology

Science.gov (United States)

Srivastava, Tripti K.; Waghmare, Lalitbhushan S.; Jagzape, Arunita; Mishra, Vedprakash

2015-01-01

A tutorial is a period of instruction given by a university or college tutor to an individual or a very small group. Essentially, it is a small class of a few students in which the tutor (a lecturer or other academic staff member) gives individual attention to every learner. The tutorial focuses on certain subject areas and generally proceeds with…

Tutorial on Online Partial Evaluation

Directory of Open Access Journals (Sweden)

William R. Cook

2011-09-01

Full Text Available This paper is a short tutorial introduction to online partial evaluation. We show how to write a simple online partial evaluator for a simple, pure, first-order, functional programming language. In particular, we show that the partial evaluator can be derived as a variation on a compositionally defined interpreter. We demonstrate the use of the resulting partial evaluator for program optimization in the context of model-driven development.

IMPLEMENTASI MODEL TUTORIAL BERBASIS KOMPUTER FISIOLOGI HEWAN UNTUK MEMBEKALI KEMAMPUAN REKONSTRUKSI KONSEP MAHASISWA CALON GURU BIOLOGI

Directory of Open Access Journals (Sweden)

Adeng Slamet

2015-03-01

Full Text Available Penelitian ini bertujuan untuk membandingkan model perkuliahan fisiologi hewan yang diharapkan mampu membekali kemampuan rekonstruksi konsep bagi mahasiswa calon guru biologi. Strategi perkuliahan ditempuh melalui implementasi model tutorial berbasis komputer. Sebanyak 80 orang mahasiswa S1 calon guru biologi dibagi ke dalam dua kelompok, 41 mahasiswa mengikuti perkuliahan model tutorial komputer, dan 39 mahasiswa mengikuti perkuliahan konvensional. Kemampuan rekonstruksi konsep diukur dengan membandingkan skor sebelum pembelajaran (pretes dengan setelah implementasi model (postes di antara kedua kelompok belajar. Selain itu, untuk mengungkap pandangan mahasiswa mengenai pengalaman belajarnya, seperangkat angket disebarkan kepada mahasiswa yang mengikuti model perkuliahan.  Efektivitas program perkuliahan dievaluasi dengan tes tertulis bentuk respon terbatas pada mahasiswa yang mengikuti program perkuliahan model tutorial komputer dibandingkan dengan mahasiswa dari kelompok konvensional. Hasil penelitian menunjukkan secara keseluruhan terjadi peningkatan  kemampuan rekonstruksi konsep pada kedua kelompok belajar, namun mahasiswa yang mengikuti perkuliahan model tutorial berbasis komputer menunjukkan peningkatan yang lebih tinggi dibandingkan kelompok mahasiswa peserta perkuliahan konvensional. Mahasiswa menanggapi positif implementasi model tutorial berbasis komputer dalam perkuliahan fisiologi hewan. Dapat disimpulkan bahwa penerapan model tutorial berbasis komputer pada penelitian ini dinyatakan lebih efektif dan mampu  membekali mahasiwa calon guru biologi dalam meningkatkan kemampuan  rekonstruksi konsep.

Assessing the Effectiveness of Web-Based Tutorials Using Pre-and Post-Test Measurements

Science.gov (United States)

Guy, Retta Sweat; Lownes-Jackson, Millicent

2012-01-01

Computer technology in general and the Internet in particular have facilitated as well as motivated the development of Web-based tutorials (MacKinnon & Williams, 2006). The current research study describes a pedagogical approach that exploits the use of self-paced, Web-based tutorials for assisting students with reviewing grammar and mechanics…

Maximum Feedrate Interpolator for Multi-axis CNC Machining with Jerk Constraints

OpenAIRE

Beudaert , Xavier; Lavernhe , Sylvain; Tournier , Christophe

2012-01-01

A key role of the CNC is to perform the feedrate interpolation which means to generate the setpoints for each machine tool axis. The aim of the VPOp algorithm is to make maximum use of the machine tool respecting both tangential and axis jerk on rotary and linear axes. The developed algorithm uses an iterative constraints intersection approach. At each sampling period, all the constraints given by each axis are expressed and by intersecting all of them the allowable interval for the next poin...

The effectiveness of web-based, multimedia tutorials for teaching methods of human body composition analysis.

Science.gov (United States)

Buzzell, Paul R; Chamberlain, Valerie M; Pintauro, Stephen J

2002-12-01

This study examined the effectiveness of a series of Web-based, multimedia tutorials on methods of human body composition analysis. Tutorials were developed around four body composition topics: hydrodensitometry (underwater weighing), dual-energy X-ray absorptiometry, bioelectrical impedance analysis, and total body electrical conductivity. Thirty-two students enrolled in the course were randomly assigned to learn the material through either the Web-based tutorials only ("Computer"), a traditional lecture format ("Lecture"), or lectures supplemented with Web-based tutorials ("Both"). All students were administered a validated pretest before randomization and an identical posttest at the completion of the course. The reliability of the test was 0.84. The mean score changes from pretest to posttest were not significantly different among the groups (65.4 plus minus 17.31, 78.82 plus minus 21.50, and 76 plus minus 21.22 for the Computer, Both, and Lecture groups, respectively). Additionally, a Likert-type assessment found equally positive attitudes toward all three formats. The results indicate that Web-based tutorials are as effective as the traditional lecture format for teaching these topics.

You Tube Video Genres. Amateur how-to Videos Versus Professional Tutorials

OpenAIRE

Andreea Mogoș; Constantin Trofin

2015-01-01

In spite of the fact that there is a vast literature on traditional textual and visual genre classifications, the categorization of web content is still a difficult task, because this medium is fluid, unstable and fast-paced on one hand and, on the other hand, the genre classifications are socially constructed through the tagging process and the interactions (commenting, rating, chatting). This paper focuses on YouTube tutorials and aims to compare video tutorials produced by professionals wi...

Comparative Investigation on Tool Wear during End Milling of AISI H13 Steel with Different Tool Path Strategies

Science.gov (United States)

Adesta, Erry Yulian T.; Riza, Muhammad; Avicena

2018-03-01

Tool wear prediction plays a significant role in machining industry for proper planning and control machining parameters and optimization of cutting conditions. This paper aims to investigate the effect of tool path strategies that are contour-in and zigzag tool path strategies applied on tool wear during pocket milling process. The experiments were carried out on CNC vertical machining centre by involving PVD coated carbide inserts. Cutting speed, feed rate and depth of cut were set to vary. In an experiment with three factors at three levels, Response Surface Method (RSM) design of experiment with a standard called Central Composite Design (CCD) was employed. Results obtained indicate that tool wear increases significantly at higher range of feed per tooth compared to cutting speed and depth of cut. This result of this experimental work is then proven statistically by developing empirical model. The prediction model for the response variable of tool wear for contour-in strategy developed in this research shows a good agreement with experimental work.

Development process and data management of TurnSTEP, a STEP-compliant CNC system for turning

NARCIS (Netherlands)

Choi, I.; Suh, S.-H; Kim, K.; Song, M.S.; Jang, M.; Lee, B.-E.

2006-01-01

TurnSTEP is one of the earliest STEP-compliant CNC systems for turning. Based on the STEP-NC data model formalized as ISO 14649-12 and 121, it is designed to support intelligent and autonomous control of NC machines for e-manufacturing. The present paper introduces the development process and data

Technical and Symbolic Knowledge in CNC Machining: A Study of Technical Workers of Different Backgrounds.

Science.gov (United States)

Martin, Laura M. W.; Beach, King

Performances of 45 individuals with varying degrees of formal and informal training in machining and programming were compared on tasks designed to tap intellectual changes that may occur with the introduction of computer numerical control (CNC). Participants--30 machinists, 8 machine operators, and 7 engineers--were asked background questions and…

Rapid proto typing of dental prosthesis by means of a feldspathic glass composite mixed with muscovite mica via CAD/CAM

International Nuclear Information System (INIS)

Garcia Junior, E.S.; Gomes Junior, G.G.; Fonseca, M.D.; Moraes, E.E.S.; Ogasawara, T.

2010-01-01

The work consists in the use and integration of CAD/CAM tools as a process of design and manufacture of a rapid prototyping of dental prosthesis by machining using a CNC milling machine. The material machined to obtain the dental prosthesis were cylindrical blocks of a Feldspathic glass composite mixed with muscovite mica in various percentages (15%, 40% and 80%), which was resigned under biaxial pressing and sintered in vacuum at temperatures from 800 to 1100 deg C. The composite was characterized by XRD and SEM. The results show that increasing the crystallization of leucite is consequent to the temperature increase, and that the use of CAD/CAM system using a CNC milling machine is feasible to obtain dental prosthesis. (author)

Rapid proto typing of dental prosthesis by means of a feldspathic glass composite mixed with muscovite mica via CAD/CAM; Prototipagem rapida de proteses dentarias por meio de um composito de vidro feldspatico misturado com mica moscovita via CAD/CAM

Energy Technology Data Exchange (ETDEWEB)

Garcia Junior, E.S.; Gomes Junior, G.G.; Fonseca, M.D.; Moraes, E.E.S.; Ogasawara, T., E-mail: edil@metalmat.ufrj.b [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Dept. de Engenharia Metalurgica e Materiais

2010-07-01

The work consists in the use and integration of CAD/CAM tools as a process of design and manufacture of a rapid prototyping of dental prosthesis by machining using a CNC milling machine. The material machined to obtain the dental prosthesis were cylindrical blocks of a Feldspathic glass composite mixed with muscovite mica in various percentages (15%, 40% and 80%), which was resigned under biaxial pressing and sintered in vacuum at temperatures from 800 to 1100 deg C. The composite was characterized by XRD and SEM. The results show that increasing the crystallization of leucite is consequent to the temperature increase, and that the use of CAD/CAM system using a CNC milling machine is feasible to obtain dental prosthesis. (author)

Physical Parameters of the Overcontact Binary AH Cnc in the Old Open Cluster M 67

NARCIS (Netherlands)

Yakut, K.; Aerts, C.C.

2006-01-01

We present a photometric study of the overcontact binary AH Cnc. The CCD observations were done with the Russian-Turkish 1.5 m telescope and the light-curve was solved with the Wilson-Devinney code. The physical parameters of the components have been deduced as M₁ = 1.22 Msun,

Introduction to OAI and harvesting, tutorial 3

CERN Multimedia

CERN. Geneva

2005-01-01

1. Coverage: - Overview of key Open Archives Initiative (OAI) concepts. - Development of the OAI Protocol for Metadata Harvesting (OAI-PMH). - Non-technical introduction to main underlying technical ideas. - Some considerations regarding implementation of OAI-PMH, with particular focus on harvesting issues. For those who would like an introduction to, or revision of, the main concepts associated with OAI then this session will provide an ideal foundation for the rest of the OAI4 workshop. 2. Audience: Decision-makers, Managers, Technical staff with no previous OAI-PMH knowledge. This is a tutorial for those who may not themselves do hands-on technical implementation, but might make or advise on decisions whether or not to implement particular solutions. They may have staff who are implementers, or may work with them. Technical staff are likely to prefer the technical tutorials, but may want to attend this one if they are at the very early stage of simply requiring background information. 3. At the end of the ...

Using Visual Assessments and Tutorials to Teach Solar System Concepts in Introductory Astronomy

Science.gov (United States)

LoPresto, Michael C.

2010-01-01

Visual assessments and tutorials are instruments that rely on student construction and/or examination of pictures and/or diagrams rather than multiple choice and/or short answer questions. Being a very visual subject, astronomy lends itself to assessments and tutorials of this type. What follows is a report on the results of the use of visual…

L'ajuda tutorial en els MOOCs: un nou enfocament en l'acció tutorial

Directory of Open Access Journals (Sweden)

Rosario Medina-Salguero

2013-12-01

Full Text Available En el present treball s'expon un analisis de l'accio tutorial en una nova modalitat d'ensenyança-aprenentage, els MOOCS. Per a açò, hem portat a veta un estudi de material documental que permet reconstruir els acontenyiments que estan succeint en l'actualitat en els MOOCS. Els resultats mos indiquen com se configura esta nova tendencia d'aprenentage a nivell internacional i nacional i com s'establix l'ajuda pedagogica en els MOOCS.

78 FR 50135 - CNC Development, Ltd., Exousia Advanced Materials, Inc., and South American Minerals, Inc.; Order...

Science.gov (United States)

2013-08-16

... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] CNC Development, Ltd., Exousia Advanced Materials, Inc., and South American Minerals, Inc.; Order of Suspension of Trading August 14, 2013. It... securities of South American Minerals, Inc. because it has not filed any periodic reports since it filed a...

Tutorial: Speech Assessment for Multilingual Children Who Do Not Speak the Same Language(s) as the Speech-Language Pathologist.

Science.gov (United States)

McLeod, Sharynne; Verdon, Sarah

2017-08-15

The aim of this tutorial is to support speech-language pathologists (SLPs) undertaking assessments of multilingual children with suspected speech sound disorders, particularly children who speak languages that are not shared with their SLP. The tutorial was written by the International Expert Panel on Multilingual Children's Speech, which comprises 46 researchers (SLPs, linguists, phoneticians, and speech scientists) who have worked in 43 countries and used 27 languages in professional practice. Seventeen panel members met for a 1-day workshop to identify key points for inclusion in the tutorial, 26 panel members contributed to writing this tutorial, and 34 members contributed to revising this tutorial online (some members contributed to more than 1 task). This tutorial draws on international research evidence and professional expertise to provide a comprehensive overview of working with multilingual children with suspected speech sound disorders. This overview addresses referral, case history, assessment, analysis, diagnosis, and goal setting and the SLP's cultural competence and preparation for working with interpreters and multicultural support workers and dealing with organizational and government barriers to and facilitators of culturally competent practice. The issues raised in this tutorial are applied in a hypothetical case study of an English-speaking SLP's assessment of a multilingual Cantonese- and English-speaking 4-year-old boy. Resources are listed throughout the tutorial.

The Effectiveness of a 3D Computerized Tutorial to Enhance Learning of the Canine Larynx and Hyoid Apparatus.

Science.gov (United States)

Nemanic, Sarah; Mills, Serena; Viehdorfer, Matt; Clark, Terri; Bailey, Mike

Teaching the anatomy of the canine larynx and hyoid apparatus is challenging because dissection disassembles and/or damages these structures, making it difficult to understand their three-dimensional (3D) anatomy and spatial interrelationships. This study assessed the effectiveness of an interactive, computerized 3D tutorial for teaching the anatomy of the canine larynx and hyoid apparatus using a randomized control design with students enrolled in the first-year professional program at Oregon State University College of Veterinary Medicine. All first-year students from 2 consecutive years were eligible. All students received the traditional methods of didactic teaching and dissection to learn the anatomy of the canine larynx and hyoid apparatus, after which they were divided into two statistically equal groups based on their cumulative anatomy test scores from the prior term. The tutorial group received an interactive, computerized tutorial developed by the investigators containing 3D images of the canine larynx and hyoid apparatus, while the control group received the same 3D images without the computerized tutorial. Both groups received the same post-learning assessment and survey. Sixty-three first-year students participated in the study, 28 in the tutorial group, and 35 in the control group. Post-learning assessment and survey scores were both significantly higher among students in the computerized tutorial group than those in the control group. This study demonstrates that a 3D computerized tutorial is more effective in teaching the anatomy of the canine hyoid apparatus and larynx than 3D images without a tutorial. Students likewise rated their learning experience higher when using the 3D computerized tutorial.

Statistical Tutorial | Center for Cancer Research

Science.gov (United States)

Recent advances in cancer biology have resulted in the need for increased statistical analysis of research data.  ST is designed as a follow up to Statistical Analysis of Research Data (SARD) held in April 2018.  The tutorial will apply the general principles of statistical analysis of research data including descriptive statistics, z- and t-tests of means and mean

Effectiveness of interactive tutorials in promoting "which-path" information reasoning in advanced quantum mechanics

Science.gov (United States)

Maries, Alexandru; Sayer, Ryan; Singh, Chandralekha

2017-12-01

Research suggests that introductory physics students often have difficulty using a concept in contexts different from the ones in which they learned it without explicit guidance to help them make the connection between the different contexts. We have been investigating advanced students' learning of quantum mechanics concepts and have developed interactive tutorials which strive to help students learn these concepts. Two such tutorials, focused on the Mach-Zehnder interferometer (MZI) and the double-slit experiment (DSE), help students learn how to use the concept of "which-path" information to reason about the presence or absence of interference in these two experiments in different situations. After working on a pretest that asked students to predict interference in the MZI with single photons and polarizers of various orientations placed in one or both paths of the MZI, students worked on the MZI tutorial which, among other things, guided them to reason in terms of which-path information in order to predict interference in similar situations. We investigated the extent to which students were able to use reasoning related to which-path information learned in the MZI tutorial to answer analogous questions on the DSE (before working on the DSE tutorial). After students worked on the DSE pretest they worked on a DSE tutorial in which they learned to use the concept of which-path information to answer questions about interference in the DSE with single particles with mass sent through the two slits and a monochromatic lamp placed between the slits and the screen. We investigated if this additional exposure to the concept of which-path information promoted improved learning and performance on the DSE questions with single photons and polarizers placed after one or both slits. We find evidence that both tutorials promoted which-path information reasoning and helped students use this reasoning appropriately in contexts different from the ones in which they had learned

The MAGIC of Web Tutorials: How One Library (Re)Focused Its Delivery of Online Learning Objects on Users

Science.gov (United States)

Hess, Amanda Nichols

2013-01-01

Oakland University (OU) Libraries undertook an assessment of how to leverage its resources to make online tutorials more focused on users' needs. A multi-part assessment process reconsidered Web tutorials offerings through the lenses of faculty and staff feedback, literature review, and an analysis of other universities' online tutorial offerings.…

Online Bioinformatics Tutorials | Office of Cancer Genomics

Science.gov (United States)

Bioinformatics is a scientific discipline that applies computer science and information technology to help understand biological processes. The NIH provides a list of free online bioinformatics tutorials, either generated by the NIH Library or other institutes, which includes introductory lectures and "how to" videos on using various tools.

An open CAM system for dentistry on the basis of China-made 5-axis simultaneous contouring CNC machine tool and industrial CAM software.

Science.gov (United States)

Lu, Li; Liu, Shusheng; Shi, Shenggen; Yang, Jianzhong

2011-10-01

China-made 5-axis simultaneous contouring CNC machine tool and domestically developed industrial computer-aided manufacture (CAM) technology were used for full crown fabrication and measurement of crown accuracy, with an attempt to establish an open CAM system for dental processing and to promote the introduction of domestic dental computer-aided design (CAD)/CAM system. Commercially available scanning equipment was used to make a basic digital tooth model after preparation of crown, and CAD software that comes with the scanning device was employed to design the crown by using domestic industrial CAM software to process the crown data in order to generate a solid model for machining purpose, and then China-made 5-axis simultaneous contouring CNC machine tool was used to complete machining of the whole crown and the internal accuracy of the crown internal was measured by using 3D-MicroCT. The results showed that China-made 5-axis simultaneous contouring CNC machine tool in combination with domestic industrial CAM technology can be used for crown making and the crown was well positioned in die. The internal accuracy was successfully measured by using 3D-MicroCT. It is concluded that an open CAM system for dentistry on the basis of China-made 5-axis simultaneous contouring CNC machine tool and domestic industrial CAM software has been established, and development of the system will promote the introduction of domestically-produced dental CAD/CAM system.

Evaluation of metal-ceramic bond characteristics of three dental Co-Cr alloys prepared with different fabrication techniques.

Science.gov (United States)

Wang, Hongmei; Feng, Qing; Li, Ning; Xu, Sheng

2016-12-01

Limited information is available regarding the metal-ceramic bond strength of dental Co-Cr alloys fabricated by casting (CAST), computer numerical control (CNC) milling, and selective laser melting (SLM). The purpose of this in vitro study was to evaluate the metal-ceramic bond characteristics of 3 dental Co-Cr alloys fabricated by casting, computer numerical control milling, and selective laser melting techniques using the 3-point bend test (International Organization for Standardization [ISO] standard 9693). Forty-five specimens (25×3×0.5 mm) made of dental Co-Cr alloys were prepared by CAST, CNC milling, and SLM techniques. The morphology of the oxidation surface of metal specimens was evaluated by scanning electron microscopy (SEM). After porcelain application, the interfacial characterization was evaluated by SEM equipped with energy-dispersive spectrometry (EDS) analysis, and the metal-ceramic bond strength was assessed with the 3-point bend test. Failure type and elemental composition on the debonding interface were assessed by SEM/EDS. The bond strength was statistically analyzed by 1-way ANOVA and Tukey honest significant difference test (α=.05). The oxidation surfaces of the CAST, CNC, and SLM groups were different. They were porous in the CAST group but compact and irregular in the CNC and SLM groups. The metal-ceramic interfaces of the SLM and CNC groups showed excellent combination compared with those of the CAST group. The bond strength was 37.7 ±6.5 MPa for CAST, 43.3 ±9.2 MPa for CNC, and 46.8 ±5.1 MPa for the SLM group. Statistically significant differences were found among the 3 groups tested (P=.028). The debonding surfaces of all specimens exhibited cohesive failure mode. The oxidation surface morphologies and thicknesses of dental Co-Cr alloys are dependent on the different fabrication techniques used. The bond strength of all 3 groups exceed the minimum acceptable value of 25 MPa recommended by ISO 9693; hence, dental Co-Cr alloy

Increase efficiency CNC lathe with the help of fuzzy logic controller (FLC

Directory of Open Access Journals (Sweden)

Mošorinski Predrag R.

2016-01-01

Full Text Available This paper discusses the process of increasing the effectiveness of CNC lathe for carrying out the appropriate experiments. Experiments are related to the plastics processing machine and programming fuzzy logic controller (FLC for the requirements of machining. Input parameters of the FLCare obtained as a result of previous experimental parameters set by experience and with a great subjective impact of technologists. Expected results of FLC's settings are based on the complete autonomy of the process and eliminating subjective errors.

Random and Systematic Errors Share in Total Error of Probes for CNC Machine Tools

Directory of Open Access Journals (Sweden)

Adam Wozniak

2018-03-01

Full Text Available Probes for CNC machine tools, as every measurement device, have accuracy limited by random errors and by systematic errors. Random errors of these probes are described by a parameter called unidirectional repeatability. Manufacturers of probes for CNC machine tools usually specify only this parameter, while parameters describing systematic errors of the probes, such as pre-travel variation or triggering radius variation, are used rarely. Systematic errors of the probes, linked to the differences in pre-travel values for different measurement directions, can be corrected or compensated, but it is not a widely used procedure. In this paper, the share of systematic errors and random errors in total error of exemplary probes are determined. In the case of simple, kinematic probes, systematic errors are much greater than random errors, so compensation would significantly reduce the probing error. Moreover, it shows that in the case of kinematic probes commonly specified unidirectional repeatability is significantly better than 2D performance. However, in the case of more precise strain-gauge probe systematic errors are of the same order as random errors, which means that errors correction or compensation, in this case, would not yield any significant benefits.

Oracle support provides a range of new tutorials

CERN Multimedia

2012-01-01

The IT DB is pleased to announce a new series of Oracle tutorials, with the proposed schedule. Note that these tutorials will take place in the Filtration Plant (Building 222) and that no registration is required.   4 June (Monday) 09:00 Oracle Architecture, Przemyslaw Adam Radowiecki The objective is to go through Oracle database physical and logical structures, highlighting the consequences of some of Oracle's internal design choices for developers of database applications. The presentation defines Oracle-related basic terms and illustrates them based on the database architecture. The following topics will be discussed: • Database with its physical and logical structures (tablespace, segment, extent, block, database user, schema, user's quota) • Single instance (significant memory structures: buffer cache, shared pool) • Real Application Cluster (RAC) • Connecting to the database (TNS, database service) • SQL statement processing (h...

Using Active-Learning Pedagogy to Develop Essay-Writing Skills in Introductory Political Theory Tutorials

Science.gov (United States)

Murphy, Michael P. A.

2017-01-01

Building on prior research into active learning pedagogy in political science, I discuss the development of a new active learning strategy called the "thesis-building carousel," designed for use in political theory tutorials. This use of active learning pedagogy in a graduate student-led political theory tutorial represents the overlap…

Uranium-mill appraisal program

International Nuclear Information System (INIS)

Everett, R.J.; Cain, C.L.

1982-08-01

The results of special team appraisals at NRC-licensed uranium mills in the period May to November 1981 are reported. Since the Three Mile Island accident, NRC management has instituted a program of special team appraisals of radiation protection programs at certain NRC-licensed facilities. These appraisals were designed to identify weaknesses and strengths in NRC-licensed programs, including those areas not covered by explicit regulatory requirements. The regulatory requirements related to occupational radiation protection and environmental monitoring at uranium mills have been extensively upgraded in the past few years. In addition, there was some NRC staff concern with respect to the effectiveness of NRC licensing and inspection programs. In response to this concern and to changes in mill requirements, the NRC staff recommended that team appraisals be conducted at mills to determine the adequacy of mill programs, the effectiveness of the new requirements, and mill management implementation of programs and requirements. This report describes the appraisal scope and methodology as well as summary findings and conclusions. Significant weaknesses identified during the mill appraisals are discussed as well as recommendations for improvements in uranium mill programs and mill licensing and inspection

Effects of implementation of problem-based learning tutorials on fifth-year pharmacy students and future issues.

Science.gov (United States)

Sato, Atsuko; Morone, Mieko; Azuma, Yutaka

2011-01-01

At Tohoku Pharmaceutical University, problem-based learning (PBL) tutorials were incorporated into "prescription analysis" and "case analysis" for fifth-year students in 2010 with the following objectives: ① application and confirmation of acquired knowledge and skills, and acquisition of ② communication ability, ③ presentation ability, ④ cooperativeness through groupwork, and ⑤ information collecting ability. In the present study, we conducted a questionnaire survey on a total of 158 fifth-year students in order to investigate the educational benefits of PBL tutorials. The results showed that the above five objectives of PBL tutorials were being achieved, and confirmed the educational benefits expected of PBL tutorials. In contrast, it was found to be necessary to improve the contents of scenarios and lectures, time allocation regarding schedules, the learning environment, the role of tutors, and other matters. In order to maximize the educational benefits of PBL tutorials, it will be necessary in the future to continue to conduct surveys on students and make improvements to the curriculum based on survey results.

Generation of Tutorial Dialogues: Discourse Strategies for Active Learning

National Research Council Canada - National Science Library

Evans, Martha

1998-01-01

With the support of the Cognitive Science Program of ONR, we are developing the capability to generate complex natural language tutorial dialogues for an intelligent tutoring system designed to help...

Far Ultraviolet Spectroscopy of Three Long Period Nova-Like Variables, V363 Aur, AC Cnc and RZ Gru

Science.gov (United States)

Bisol, Alexandra; Sion, E. M.

2011-01-01

We have selected three nova-like variables: V363 Aur, RZ Gru and AC Cnc, all of which are UX UMa types, having similar orbital periods well beyond the 3 to 4 hour range where most nova-likes are found. All should have very similar secondary stars given the fact that they their physical parameters are so similar. V363 Aur is a bona fide SW Sex star, and AC Cnc is a probable one, while RZ Gru is not a member of the SW Sex subclass. Our objective is to carry out the first synthetic spectral analysis of far ultraviolet spectra of the three systems using state-of-the-art models both of accretion disks and photospheres. Therefore we shall compare the distances we obtain from the best fitting synthetic spectral models to other distance estimates in the literature. We present model-derived accretion rates and distances for all three systems. The FUV flux range of RZ Gru and V363 Aur is dominated by radiation from an optically thick, steady state, accretion but for AC Cnc, we find that a hot white dwarf accounts for 70% of the FUV flux. We compare the FUV characteristics and physical properties of these three long period nova-like systems to the properties of other nova-likes at shorter periods. This work was supported in part by NSF grant AST0807892 to Villanova University.

Automated problem generation in Learning Management Systems: a tutorial

Directory of Open Access Journals (Sweden)

Jaime Romero

2016-07-01

Full Text Available The benefits of solving problems have been widely acknowledged by literature. Its implementation in e–learning platforms can make easier its management and the learning process itself. However, its implementation can also become a very time–consuming task, particularly when the number of problems to generate is high. In this tutorial we describe a methodology that we have developed aiming to alleviate the workload of producing a great deal of problems in Moodle for an undergraduate business course. This methodology follows a six-step process and allows evaluating student’s skills in problem solving, minimizes plagiarism behaviors and provides immediate feedback. We expect this tutorial encourage other educators to apply our six steps process, thus benefiting themselves and their students of its advantages.

Staying on Top of Your Game and Scoring Big with Adobe Presenter Multimedia Tutorials

Science.gov (United States)

Koury, Regina; Francis, Marcia J.; Gray, Catherine J.; Jardine, Spencer J.; Guo, Ruiling

2010-01-01

In order to reach distance students in times of financial uncertainty, librarians must be creative. While much has been written about Camtasia, Captivate and Jing tutorial software, Adobe Presenter, a Microsoft PowerPoint plug-in, has not been discussed. This article describes how our library team created multimedia tutorial projects at Idaho…

Assessing the flexibility of research-based instructional strategies: Implementing tutorials in introductory physics in the lecture environment

Science.gov (United States)

Kryjevskaia, Mila; Boudreaux, Andrew; Heins, Dustin

2014-03-01

Materials from Tutorials in Introductory Physics, originally designed and implemented by the Physics Education Group at the University of Washington, were used in modified form as interactive lectures under conditions significantly different from those suggested by the curriculum developers. Student learning was assessed using tasks drawn from the physics education research literature. Use of tutorials in the interactive lecture format yielded gains in student understanding comparable to those obtained through the canonical tutorial implementation at the University of Washington, suggesting that student engagement with the intellectual steps laid out in the tutorials, rather than the specific strategies used in facilitating such engagement, plays the central role in promoting student learning. We describe the implementation details and assessment of student learning for two different tutorials: one focused on mechanical waves, used at North Dakota State University, and one on Galilean relativity, used at Western Washington University. Also discussed are factors that may limit the generalizability of the results.

The Implementation of Blended Learning Using Android-Based Tutorial Video in Computer Programming Course II

Science.gov (United States)

Huda, C.; Hudha, M. N.; Ain, N.; Nandiyanto, A. B. D.; Abdullah, A. G.; Widiaty, I.

2018-01-01

Computer programming course is theoretical. Sufficient practice is necessary to facilitate conceptual understanding and encouraging creativity in designing computer programs/animation. The development of tutorial video in an Android-based blended learning is needed for students’ guide. Using Android-based instructional material, students can independently learn anywhere and anytime. The tutorial video can facilitate students’ understanding about concepts, materials, and procedures of programming/animation making in detail. This study employed a Research and Development method adapting Thiagarajan’s 4D model. The developed Android-based instructional material and tutorial video were validated by experts in instructional media and experts in physics education. The expert validation results showed that the Android-based material was comprehensive and very feasible. The tutorial video was deemed feasible as it received average score of 92.9%. It was also revealed that students’ conceptual understanding, skills, and creativity in designing computer program/animation improved significantly.

An Audit of the Effectiveness of Large Group Neurology Tutorials for Irish Undergraduate Medical Students

LENUS (Irish Health Repository)

Kearney, H

2016-07-01

The aim of this audit was to determine the effectiveness of large group tutorials for teaching neurology to medical students. Students were asked to complete a questionnaire rating their confidence on a ten point Likert scale in a number of domains in the undergraduate education guidelines from the Association of British Neurologists (ABN). We then arranged a series of interactive large group tutorials for the class and repeated the questionnaire one month after teaching. In the three core domains of neurological: history taking, examination and differential diagnosis, none of the students rated their confidence as nine or ten out of ten prior to teaching. This increased to 6% for history taking, 12 % in examination and 25% for differential diagnosis after eight weeks of tutorials. This audit demonstrates that in our centre, large group tutorials were an effective means of teaching, as measured by the ABN guidelines in undergraduate neurology.

Tutorial de calcul poromécanique avec le logiciel Abaqus

OpenAIRE

Bonelli, S.

2011-01-01

/ Ce tutorial est destiné à apprendre à réaliser avec Abaqus, sous CAE, un calcul de poroélasticité linéaire. Il est écrit de telle sorte que quelqu'un n'ayant jamais utilisé Abaqus, mais ayant des connaissances de base en mécanique des milieux poreux d'une part, et en éléments-finis d'autre part, puisse réaliser un tel calcul en partant de zéro. Toutefois, il ne s'agit en aucun cas d'un tutorial sur Abaqus ui-même, ni sur la méthode des éléments-finis.

Cytopathology whole slide images and adaptive tutorials for postgraduate pathology trainees: a randomized crossover trial.

Science.gov (United States)

Van Es, Simone L; Kumar, Rakesh K; Pryor, Wendy M; Salisbury, Elizabeth L; Velan, Gary M

2015-09-01

To determine whether cytopathology whole slide images and virtual microscopy adaptive tutorials aid learning by postgraduate trainees, we designed a randomized crossover trial to evaluate the quantitative and qualitative impact of whole slide images and virtual microscopy adaptive tutorials compared with traditional glass slide and textbook methods of learning cytopathology. Forty-three anatomical pathology registrars were recruited from Australia, New Zealand, and Malaysia. Online assessments were used to determine efficacy, whereas user experience and perceptions of efficiency were evaluated using online Likert scales and open-ended questions. Outcomes of online assessments indicated that, with respect to performance, learning with whole slide images and virtual microscopy adaptive tutorials was equivalent to using traditional methods. High-impact learning, efficiency, and equity of learning from virtual microscopy adaptive tutorials were strong themes identified in open-ended responses. Participants raised concern about the lack of z-axis capability in the cytopathology whole slide images, suggesting that delivery of z-stacked whole slide images online may be important for future educational development. In this trial, learning cytopathology with whole slide images and virtual microscopy adaptive tutorials was found to be as effective as and perceived as more efficient than learning from glass slides and textbooks. The use of whole slide images and virtual microscopy adaptive tutorials has the potential to provide equitable access to effective learning from teaching material of consistently high quality. It also has broader implications for continuing professional development and maintenance of competence and quality assurance in specialist practice. Copyright © 2015 Elsevier Inc. All rights reserved.

Online Job Tutorials @ the Public Library: Best Practices from Carnegie Library of Pittsburgh's Job & Career Education Center

Directory of Open Access Journals (Sweden)

Rhea M. Hebert

2013-09-01

Full Text Available This article describes the Job & Career Education Center (JCEC tutorial project completed in September of 2012. The article also addresses the website redesign implemented to highlight the tutorials and improve user engagement with JCEC online resources. Grant monies made it possible for a Digital Outreach Librarian to create a series of tutorials with the purpose of providing job-related assistance beyond the JCEC in the Carnegie Library of Pittsburgh—Main location. Benchmarking, planning, implementation, and assessment are addressed. A set of best practices for all libraries (public, academic, school, special are presented. Best practices are applicable to tutorials created with software other than Camtasia, the software used by the JCEC project.

Approximating Literacy Practices in Tutorials: What Is Learned and What Matters for Teacher Preparation

Science.gov (United States)

Hoffman, James V.; Wetzel, Melissa Mosley; Peterson, Katie

2016-01-01

In this study, we examined the learning of preservice teachers associated with the features of a literacy tutorial experience. Our qualitative study focused on the close inspection of the experiences of 7 focus cases out of the 19 preservice teachers enrolled in our program across a one-semester tutorial experience. Through our research we…

The Purpose of Tutorial Groups: Social Influence and the Group as Means and Objective

Science.gov (United States)

Rosander, Michael; Chiriac, Eva Hammar

2016-01-01

The aim of this study was to investigate how first-year students view the purpose of tutorial groups in problem-based learning. In all, 147 students from 24 groups participated, providing 399 statements. Data were analysed using thematic analysis. The results showed a focus on both learning and social influence. Learning involved the tutorial as…

Position paper: Web tutorials and Information Literacy research

DEFF Research Database (Denmark)

Hyldegård, Jette

2011-01-01

Position paper on future research challenges regarding web tutorials with the aim of supporting and facilitating Information Literacy in an academic context. Presented and discussed at the workshop: Social media & Information Practices, track on Information literacy practices, University of Borås...

University tutorials in the setting of the European Higher Education Area: current profiles

Directory of Open Access Journals (Sweden)

Carolina FERNÁNDEZ-SALINERO MIGUEL

2014-07-01

Full Text Available In the new setting promoted by the European Higher Education Area, university guidance and tutorials have become more important than ever. We understand tutorials as part of the teaching responsibility in which a more personal interaction between professor and student, professor and novice teacher, or student and student is established, and whose goal is to guide learning according to the individual characteristics and learning styles of the individuals involved. Now is the time to set up guidance and tutorials systems for students –both during the training process and in their first professional steps– and for novice teachers also. Among such systems we can mention professor coaching, peer mentoring, professional tutoring in training centres or mentoring of an experienced university professor on the novice teacher.

Integration of micro milling highspeed spindle on a microEDM-milling machine set-up

DEFF Research Database (Denmark)

De Grave, Arnaud; Hansen, Hans Nørgaard; Andolfatto, Loic

2009-01-01

In order to cope with repositioning errors and to combine the fast removal rate of micro milling with the precision and small feature size achievable with micro EDM milling, a hybrid micro-milling and micro-EDM milling centre was built and tested. The aim was to build an affordable set-up, easy...... by micro milling. Examples of test parts are shown and used as an experimental validation....

A Tutorial on the Cross-Entropy Method

NARCIS (Netherlands)

de Boer, Pieter-Tjerk; Kroese, Dirk; Mannor, Shie; Rubinstein, Reuven Y.

The cross-entropy (CE) method is a new generic approach to combinatorial and multi-extremal optimization and rare event simulation. The purpose of this tutorial is to give a gentle introduction to the CE method. We present the CE methodology, the basic algorithm and its modi��?cations, and

Uranium Mill Tailings Management

International Nuclear Information System (INIS)

Nelson, J.D.

1982-01-01

This book presents the papers given at the Fifth Symposium on Uranium Mill Tailings Management. Advances made with regard to uranium mill tailings management, environmental effects, regulations, and reclamation are reviewed. Topics considered include tailings management and design (e.g., the Uranium Mill Tailings Remedial Action Project, environmental standards for uranium mill tailings disposal), surface stabilization (e.g., the long-term stability of tailings, long-term rock durability), radiological aspects (e.g. the radioactive composition of airborne particulates), contaminant migration (e.g., chemical transport beneath a uranium mill tailings pile, the interaction of acidic leachate with soils), radon control and covers (e.g., radon emanation characteristics, designing surface covers for inactive uranium mill tailings), and seepage and liners (e.g., hydrologic observations, liner requirements)

Metodología para la manufactura de implantes craneales a partir de imágenes DICOM y tecnologías CAD/CAM/CNC Metodología para la manufactura de implantes craneales a partir de imágenes DICOM y tecnologías CAD/CAM/CNC

Directory of Open Access Journals (Sweden)

Iván López

2005-12-01

Full Text Available El presente artículo propone una metodología para el diseño y la fabricación de implantes craneales a partir de imágenes DICOM y tecnologías CAD/CAM/CNC. Esta metodología parte de las Tomografías Axiales Computarizadas (TAC de la cabeza del paciente, con las cuales se lleva a cabo la reconstrucción tridimensional del cráneo. Luego, en el sistema CAD se reconstruye el implante variando la técnica empleada dependiendo de la región del cráneo con defecto o trauma. Una vez obtenido el modelo, se diseña el montaje y se fabrica el implante con soporte en tecnología CAM/CNC.It’s proposed a methodology in order to design and manufacture cranial implants using DICOM and CAD/CAM/CNC technologies. This methodology begins when the designer makes a three-dimensional cranial reconstruction using the Axial Computer Tomographies (ACT of the patient’s cranium. Next, using a CAD system, the designer rebuilds the implant varying the used technique depending on the affected region. Finally, the designer builds the assembling and manufactures the implant.

Automatic fitting of conical envelopes to free-form surfaces for flank CNC machining

OpenAIRE

Bo P.; Bartoň M.; Pottmann H.

2017-01-01

We propose a new algorithm to detect patches of free-form surfaces that can be well approximated by envelopes of a rotational cone under a rigid body motion. These conical envelopes are a preferable choice from the manufacturing point of view as they are, by-definition, manufacturable by computer numerically controlled (CNC) machining using the efficient flank (peripheral) method with standard conical tools. Our geometric approach exploits multi-valued vector fields that consist of vectors in...

Overview of Sustainability Studies of CNC Machining and LAM of Stainless Steel

Science.gov (United States)

Nyamekye, Patricia; Leino, Maija; Piili, Heidi; Salminen, Antti

Laser additive manufacturing (LAM), known also as 3D printing, is a powder bed fusion (PBF) type of additive manufacturing (AM) technology used to fabricate metal parts out of metal powder. The development of the technology from building prototype parts to functional parts has increased remarkably in 2000s. LAM of metals is promising technology that offers new opportunities to manufacturing and to resource efficiency. However, there is only few published articles about its sustainability. Aim in this study was to create supply chain model of LAM and CNC machining and create a methodology to carry out a life cycle inventory (LCI) data collection for these techniques. The methodology of the study was literature review and scenario modeling. The acquisition of raw material, production phase and transportations were used as basis of comparison. The modelled scenarios were fictitious and created for industries, like aviation and healthcare that often require swift delivery as well as customized parts. The results of this study showed that the use of LAM offers a possibility to reduce downtime in supply chains of spare parts and reduce part inventory more effectively than CNC machining. Also the gap between customers and business is possible to be shortened with LAM thus offering a possibility to reduce emissions due to less transportation. The results also indicated weight reduction possibility with LAM due to optimized part geometry which allow lesser amount of metallic powder to be used in making parts.

Challenge of engaging all students via self-paced interactive electronic learning tutorials for introductory physics

Directory of Open Access Journals (Sweden)

Seth DeVore

2017-05-01

Full Text Available As research-based, self-paced electronic learning tools become increasingly available, a critical issue educators encounter is implementing strategies to ensure that all students engage with them as intended. Here, we first discuss the effectiveness of electronic learning tutorials as self-paced learning tools in large enrollment brick and mortar introductory physics courses and then propose a framework for helping students engage effectively with the learning tools. The tutorials were developed via research in physics education and were found to be effective for a diverse group of introductory physics students in one-on-one implementation. Instructors encouraged the use of these tools in a self-paced learning environment by telling students that they would be helpful for solving the assigned homework problems and that the underlying physics principles in the tutorial problems would be similar to those in the in-class quizzes (which we call paired problems. We find that many students in the courses in which these interactive electronic learning tutorials were assigned as a self-study tool performed poorly on the paired problems. In contrast, a majority of student volunteers in one-on-one implementation greatly benefited from the tutorials and performed well on the paired problems. The significantly lower overall performance on paired problems administered as an in-class quiz compared to the performance of student volunteers who used the research-based tutorials in one-on-one implementation suggests that many students enrolled in introductory physics courses did not effectively engage with the tutorials outside of class and may have only used them superficially. The findings suggest that many students in need of out-of-class remediation via self-paced learning tools may have difficulty motivating themselves and may lack the self-regulation and time-management skills to engage effectively with tools specially designed to help them learn at their

Challenge of engaging all students via self-paced interactive electronic learning tutorials for introductory physics

Science.gov (United States)

DeVore, Seth; Marshman, Emily; Singh, Chandralekha

2017-06-01

As research-based, self-paced electronic learning tools become increasingly available, a critical issue educators encounter is implementing strategies to ensure that all students engage with them as intended. Here, we first discuss the effectiveness of electronic learning tutorials as self-paced learning tools in large enrollment brick and mortar introductory physics courses and then propose a framework for helping students engage effectively with the learning tools. The tutorials were developed via research in physics education and were found to be effective for a diverse group of introductory physics students in one-on-one implementation. Instructors encouraged the use of these tools in a self-paced learning environment by telling students that they would be helpful for solving the assigned homework problems and that the underlying physics principles in the tutorial problems would be similar to those in the in-class quizzes (which we call paired problems). We find that many students in the courses in which these interactive electronic learning tutorials were assigned as a self-study tool performed poorly on the paired problems. In contrast, a majority of student volunteers in one-on-one implementation greatly benefited from the tutorials and performed well on the paired problems. The significantly lower overall performance on paired problems administered as an in-class quiz compared to the performance of student volunteers who used the research-based tutorials in one-on-one implementation suggests that many students enrolled in introductory physics courses did not effectively engage with the tutorials outside of class and may have only used them superficially. The findings suggest that many students in need of out-of-class remediation via self-paced learning tools may have difficulty motivating themselves and may lack the self-regulation and time-management skills to engage effectively with tools specially designed to help them learn at their own pace. We

Instructional and regulative discourse in language tutorials: An ...

African Journals Online (AJOL)

The research is situated in the context of literature tutorials. To achieve this goal Bernstein's (1990; 1996) pedagogic discourse is employed, as it was used by Buzzelli and Johnston (2001). Keywords: language learning, learning process, teacher-student interaction, participation, potentially offensive views, pedagogic ...

Professionalizing tutors and tutorials in higher education

Directory of Open Access Journals (Sweden)

Colunga, Silvia

2012-01-01

Full Text Available The paper analyzes the necessity of professionalizing training of university teachers performing tutorial activities in higher education as a response to the demands of pupils following a part-time model. Permanent training of tutor is emphasized as a way to enhance professional and personal accomplishments. This training gives priority to educative orientation and interventional actions.

Distributed Control System Design for Portable PC Based CNC Machine

Directory of Open Access Journals (Sweden)

Roni Permana Saputra

2014-07-01

Full Text Available The demand on automated machining has been increased and emerges improvement research to achieve many goals such as portability, low cost manufacturability, interoperability, and simplicity in machine usage. These improvements are conducted without ignoring the performance analysis and usability evaluation. This research has designed a distributed control system in purpose to control a portable CNC machine. The design consists of main processing unit, secondary processing unit, motor control, and motor driver. A preliminary simulation has been conducted for performance analysis including linear accuracy and circular accuracy. The results achieved in the simulation provide linear accuracy up to 2 μm with total cost for the whole processing unit is up to 5 million IDR.

Modeling of tool path for the CNC sheet cutting machines

Science.gov (United States)

Petunin, Aleksandr A.

2015-11-01

In the paper the problem of tool path optimization for CNC (Computer Numerical Control) cutting machines is considered. The classification of the cutting techniques is offered. We also propose a new classification of toll path problems. The tasks of cost minimization and time minimization for standard cutting technique (Continuous Cutting Problem, CCP) and for one of non-standard cutting techniques (Segment Continuous Cutting Problem, SCCP) are formalized. We show that the optimization tasks can be interpreted as discrete optimization problem (generalized travel salesman problem with additional constraints, GTSP). Formalization of some constraints for these tasks is described. For the solution GTSP we offer to use mathematical model of Prof. Chentsov based on concept of a megalopolis and dynamic programming.

A Multimedia Tutorial for Charged-Particle Beam Dynamics. Final report

International Nuclear Information System (INIS)

Silbar, Richard R.

1999-01-01

In September 1995 WhistleSoft, Inc., began developing a computer-based multimedia tutorial for charged-particle beam dynamics under Phase II of a Small Business Innovative Research grant from the U.S. Department of Energy. In Phase I of this project (see its Final Report) we had developed several prototype multimedia modules using an authoring system on NeXTStep computers. Such a platform was never our intended target, and when we began Phase II we decided to make the change immediately to develop our tutorial modules for the Windows and Macintosh microcomputer market. This Report details our progress and accomplishments. It also gives a flavor of the look and feel of the presently available and upcoming modules

A Multimedia Tutorial for Charged-Particle Beam Dynamics. Final report

Energy Technology Data Exchange (ETDEWEB)

Silbar, Richard R.

1999-07-26

In September 1995 WhistleSoft, Inc., began developing a computer-based multimedia tutorial for charged-particle beam dynamics under Phase II of a Small Business Innovative Research grant from the U.S. Department of Energy. In Phase I of this project (see its Final Report) we had developed several prototype multimedia modules using an authoring system on NeXTStep computers. Such a platform was never our intended target, and when we began Phase II we decided to make the change immediately to develop our tutorial modules for the Windows and Macintosh microcomputer market. This Report details our progress and accomplishments. It also gives a flavor of the look and feel of the presently available and upcoming modules.

The Development of e-tutorial on Implementation National Curriculum 2013 for Mathematics Teacher

Science.gov (United States)

Roza, Yenita; Satria, Gita; Nur Siregar, Syarifah

2017-06-01

Curriculum 2013 is the new national Curriculum in Indonesia that is targeted to be used in all Indonesian schools in 2019. At this time the teacher training continues but the number and locations of teachers very diffuse and time constraints to be an obstacle for the government to be able to conduct training for teachers. This research resulted in the e-tutorial which is designed for mathematics teachers in studying the process of Curriculum implementation. This product will assist the government in accelerating the preparation of teachers in implementation of Curriculum 2013. This e-tutorial contains the dynamics of Curriculum development, learning model, learning assessment, lesson plan, curriculum stages of implementation and government regulation that is relevant to the implementation of Curriculum 2013. The product development started with a needs analysis through discussions with mathematics teachers about their difficulties in the implementation of the Curriculum 2013. This e-tutorial was developed using Application of Adobe Director 11. This paper discusses the results of need analysis, process development and results of product revisions made based on input from teachers during the FGD. From the discussion, it can be concluded that this e-tutorial easily understood by teachers and help them to understand the implementation of Curriculum 2013

Effects of Dry-Milling and Wet-Milling on Chemical, Physical and Gelatinization Properties of Rice Flour

Directory of Open Access Journals (Sweden)

Jitranut Leewatchararongjaroen

2016-09-01

Full Text Available Rice flour from nine varieties, subjected to dry- and wet-milling processes, was determined for its physical and chemical properties. The results revealed that milling method had an effect on properties of flour. Wet-milling process resulted in flour with significantly lower protein and ash contents and higher carbohydrate content. Wet-milled flour also tended to have lower lipid content and higher amylose content. In addition, wet-milled rice flour contained granules with smaller average size compared to dry-milled samples. Swelling power at 90 °C of wet-milled samples was higher while solubility was significantly lower than those of dry-milled flour. Dry milling process caused the destruction of the crystalline structure and yielded flour with lower crystallinity compared to wet-milling process, which resulted in significantly lower gelatinization enthalpy.

Proposing a Web-Based Tutorial System to Teach Malay Language Braille Code to the Sighted

Science.gov (United States)

Wah, Lee Lay; Keong, Foo Kok

2010-01-01

The "e-KodBrailleBM Tutorial System" is a web-based tutorial system which is specially designed to teach, facilitate and support the learning of Malay Language Braille Code to individuals who are sighted. The targeted group includes special education teachers, pre-service teachers, and parents. Learning Braille code involves memorisation…

Towards completing the cyclopropenylidene cycle: rovibrational analysis of cyclic N3+, CNN, HCNN+, and CNC.

Science.gov (United States)

Fortenberry, Ryan C; Lee, Timothy J; Huang, Xinchuan

2017-08-30

The simple aromatic hydrocarbon, cyclopropenylidene (c-C 3 H 2 ), is a known, naturally-occurring molecule. The question remains as to whether its isoelectronic, cyclic, fellow aromatics of c-N 3 + , c-CNN, HCNN + , and c-CNC - are as well. Each of these are exciting objects for observation of Titan, and the rotational constants and vibrational frequencies produced here will allow for remote sensing of Titan's atmosphere or other astrophysical or terrestrial sources. None of these four aromatic species are vibrationally strong absorbers/emitters, but the two ions, HCNN + and c-CNC - , have dipole moments of greater than 3 D and 1 D, respectively, making them good targets for rotational spectroscopic observation. Each of these molecules is shown here to exhibit its own, unique vibrational properties, but the general trends put the vibrational behavior for corresponding fundamental modes within close ranges of one another, even producing nearly the same heavy atom, symmetric stretching frequencies for HCNN + and c-C 3 H 2 at 1600 cm -1 . The c-N 3 + cation is confirmed to be fairly unstable and has almost no intensity in its ν 2 fundamental. Hence, it will likely remain difficult to characterize experimentally.

Novel CNC Grinding Process Control for Nanometric Surface Roughness for Aspheric Space Optical Surfaces

Directory of Open Access Journals (Sweden)

Jeong-Yeol Han

2004-06-01

Full Text Available Optics fabrication process for precision space optical parts includes bound abrasive grinding, loose abrasive lapping and polishing. The traditional bound abrasive grinding with bronze bond cupped diamond wheel leaves the machine marks of about 20 μm rms in height and the subsurface damage of about 1 μm rms in height to be removed by subsequent loose abrasive lapping. We explored an efficient quantitative control of precision CNC grinding. The machining parameters such as grain size, work-piece rotation speed and feed rate were altered while grinding the work-piece surfaces of 20-100 mm in diameter. The input grinding variables and the resulting surface quality data were used to build grinding prediction models using empirical and multi-variable regression analysis. The effectiveness of such grinding prediction models was then examined by running a series of precision CNC grinding operation with a set of controlled input variables and predicted output surface quality indicators. The experiment achieved the predictability down to ±20 nm in height and the surface roughness down to 36 nm in height. This study contributed to improvement of the process efficiency reaching directly the polishing and figuring process without the need for the loose abrasive lapping stage.

Investigation of the milling capabilities of the F10 Fine Grind mill using Box-Behnken designs.

Science.gov (United States)

Tan, Bernice Mei Jin; Tay, Justin Yong Soon; Wong, Poh Mun; Chan, Lai Wah; Heng, Paul Wan Sia

2015-01-01

Size reduction or milling of the active is often the first processing step in the design of a dosage form. The ability of a mill to convert coarse crystals into the target size and size distribution efficiently is highly desirable as the quality of the final pharmaceutical product after processing is often still dependent on the dimensional attributes of its component constituents. The F10 Fine Grind mill is a mechanical impact mill designed to produce unimodal mid-size particles by utilizing a single-pass two-stage size reduction process for fine grinding of raw materials needed in secondary processing. Box-Behnken designs were used to investigate the effects of various mill variables (impeller, blower and feeder speeds and screen aperture size) on the milling of coarse crystals. Response variables included the particle size parameters (D10, D50 and D90), span and milling rate. Milled particles in the size range of 5-200 μm, with D50 ranging from 15 to 60 μm, were produced. The impeller and feeder speeds were the most critical factors influencing the particle size and milling rate, respectively. Size distributions of milled particles were better described by their goodness-of-fit to a log-normal distribution (i.e. unimodality) rather than span. Milled particles with symmetrical unimodal distributions were obtained when the screen aperture size was close to the median diameter of coarse particles employed. The capacity for high throughput milling of particles to a mid-size range, which is intermediate between conventional mechanical impact mills and air jet mills, was demonstrated in the F10 mill. Prediction models from the Box-Behnken designs will aid in providing a better guide to the milling process and milled product characteristics. Copyright © 2014 Elsevier B.V. All rights reserved.

Comparing the Effectiveness of a Supplemental Online Tutorial to Traditional Instruction with Nutritional Science Students

Science.gov (United States)

Zubas, Patrice; Heiss, Cindy; Pedersen, Mary

2006-01-01

The purpose of this study was to ascertain if an online computer tutorial on diabetes mellitus, supplemented to traditional classroom lecture, is an effective tool in the education of nutrition students. Students completing a web-based tutorial as a supplement to classroom lecture displayed greater improvement in pre- vs. post-test scores compared…

Exploiting the CNC side chain in heterocyclic rearrangements: synthesis of 4(5)-acylamino-imidazoles.

Science.gov (United States)

Piccionello, Antonio Palumbo; Buscemi, Silvestre; Vivona, Nicolò; Pace, Andrea

2010-08-06

A new variation on the Boulton-Katritzky reaction is reported, namely, involving use of a CNC side chain. A novel Montmorillonite-K10 catalyzed nonreductive transamination of a 3-benzoyl-1,2,4-oxadiazole afforded a 3-(alpha-aminobenzyl)-1,2,4-oxadiazole, which was condensed with benzaldehydes to afford the corresponding imines. In the presence of strong base, these imines underwent Boulton-Katritzky-type rearrangement to afford novel 4(5)-acylaminoimidazoles.

LHC@home online tutorial for Windows users - recording

CERN Multimedia

CERN. Geneva

2016-01-01

A step-by-step online tutorial about LHC@home for Windows users by Karolina Bozek. It contains detailed instructions on how-to-join this volunteer computing project.  This 5' video is linked from http://lhcathome.web.cern.ch/join-us Also from the CDS e-learning category.

Acquaintanceship, Familiarity, and Coordinated Laughter in Writing Tutorials

Science.gov (United States)

Thonus, Terese

2008-01-01

This study compared the frequency, structure, and purposes of laughter in writing tutorials between 46 acquainted and unacquainted tutor-student pairs. Of particular interest were instances of shared, or coordinated laughter, which took the form of sequenced, simultaneous, and extended laughter. Familiarity, viewed as a continuum, was also…

Einstein-Yang-Mills from pure Yang-Mills amplitudes

Energy Technology Data Exchange (ETDEWEB)

Nandan, Dhritiman; Plefka, Jan [Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin,Zum Großen Windkanal 6, D-12489 Berlin (Germany); Schlotterer, Oliver [Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut,Am Mühlenberg 1, D-14476 Potsdam (Germany); Wen, Congkao [I.N.F.N. Sezione di Roma Tor Vergata,Via della Ricerca Scientifica, 00133 Roma (Italy)

2016-10-14

We present new relations for scattering amplitudes of color ordered gluons and gravitons in Einstein-Yang-Mills theory. Tree-level amplitudes of arbitrary multiplicities and polarizations involving up to three gravitons and up to two color traces are reduced to partial amplitudes of pure Yang-Mills theory. In fact, the double-trace identities apply to Einstein-Yang-Mills extended by a dilaton and a B-field. Our results generalize recent work of Stieberger and Taylor for the single graviton case with a single color trace. As the derivation is made in the dimension-agnostic Cachazo-He-Yuan formalism, our results are valid for external bosons in any number of spacetime dimensions. Moreover, they generalize to the superamplitudes in theories with 16 supercharges.

7 CFR 868.310 - Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice...

Science.gov (United States)

2010-01-01

... Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled Rice. (See also Â... Milled Rice Principles Governing Application of Standards § 868.310 Grades and grade requirements for the classes Long Grain Milled Rice, Medium Grain Milled Rice, Short Grain Milled Rice, and Mixed Milled Rice...

75 FR 71463 - Woodland Mills Corporation Mill Spring, NC; Notice of Revised Determination on Reconsideration

Science.gov (United States)

2010-11-23

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-73,695] Woodland Mills Corporation Mill Spring, NC; Notice of Revised Determination on Reconsideration By application dated July 22... regarding the eligibility of workers and former workers of Woodland Mills Corporation, Mill Spring, North...

Multimedia Tutorial In Physics For Foreign Students Of the Engineering Faculty Preparatory Department

Directory of Open Access Journals (Sweden)

P. G. Matukhin

2016-05-01

Full Text Available Foreign students study physics and Russian as a foreign language at the preparatory Department. They are to be trained to study different courses. During only one year the teachers of physics and Russian should help students from Asia, Africa and Latin America to get ready to study in the university. To help students in a short time to learn physical terms, to understand physics by ear, to read and write, teachers are developing the online multimedia tutorial. It is placed on the cloud OneDrive. Tutorial includes the main themes in the Mechanics. They are physical processes and phenomena, units, physical quantities, kinematics, laws of mechanics and others. The Power Point presentation slides contain information on the topics. These slides help students learn to read Russian texts on physics. There are hyperlinks to sound files on slides. Listening to those recordings, students gain the skills of physical texts listening. After each module we placed the test. Students can prepare for it using the simulator. Tests and exercise equipment made in the form of EXCEL spreadsheets. We provide our students the opportunity to view, read and listen, the tutorial files via their own mobile devices. Thus they can study physics in Russian in the classroom, or at home, but in the library, in the Park etc. Also they have access to it when they are not in Russia, and in their native countries. The tutorial presented seems to be considered as the first attempt to develop the online multimedia aimed to assist foreign students to get success in their efforts to study physics in Russian. It helps our students to learn physics in Russian faster and better. Determined are the directions of further development and improvement of the tutorial.

STUDY OF THE VIBRATION LEVEL IN CASE OF MANUFACTURING ON A CNC MACHINE-TOOL

Directory of Open Access Journals (Sweden)

Ioan Călin ROȘCA

2015-12-01

Full Text Available The paper presents the results of an experimental research performed on a CNC machine tool type ISEL-GFV considering the vibration level developed during the manufacturing of different pieces of particleboard at six processing regimes. There were recorded signals on both time and frequency domains on the three main directions. Based on recorded data there are presented the main conclusions referring to the level of vibrations and the frequencies associated to the highest levels.

Evaluation of End Mill Coatings

Energy Technology Data Exchange (ETDEWEB)

L. J. Lazarus; R. L. Hester,

2005-08-01

Milling tests were run on families of High Speed Steel (HSS) end mills to determine their lives while machining 304 Stainless Steel. The end mills tested were made from M7, M42 and T15-CPM High Speed Steels. The end mills were also evaluated with no coatings as well as with Titanium Nitride (TiN) and Titanium Carbo-Nitride (TiCN) coatings to determine which combination of HSS and coating provided the highest increase in end mill life while increasing the cost of the tool the least. We found end mill made from M42 gave us the largest increase in tool life with the least increase in cost. The results of this study will be used by Cutting Tool Engineering in determining which end mill descriptions will be dropped from our tool catalog.

Bioassay for uranium mill tailings

International Nuclear Information System (INIS)

Tschaeche, A.N.

1986-01-01

Uranium mill tailings are composed of fine sand that contains, among other things, some uranium (U/sup 238/ primarily), and all of the uranium daughters starting with /sup 230/Th that are left behind after the usable uranium is removed in the milling process. Millions of pounds of tailings are and continue to be generated at uranium mills around the United States. Discrete uranium mill tailings piles exist near the mills. In addition, the tailings materials were used in communities situated near mill sites for such purposes as building materials, foundations for buildings, pipe runs, sand boxes, gardens, etc. The Uranium Mill Tailings Remedial Action Project (UMTRAP) is a U.S. Department of Energy Program designed with the intention of removing or stabilizing the mill tailings piles and the tailings used to communities so that individuals are not exposed above the EPA limits established for such tailings materials. This paper discusses the bioassay programs that are established for workers who remove tailings from the communities in which they are placed

Biomass torrefaction mill

Science.gov (United States)

Sprouse, Kenneth M.

2016-05-17

A biomass torrefaction system includes a mill which receives a raw biomass feedstock and operates at temperatures above 400 F (204 C) to generate a dusty flue gas which contains a milled biomass product.

Influence of Chatter of VMC Arising During End Milling Operation and Cutting Conditions on Quality of Machined Surface

Directory of Open Access Journals (Sweden)

A.K.M.N. Amin, M.A. Rizal, and M. Razman

2012-08-01

Full Text Available Machine tool chatter is a dynamic instability of the cutting process. Chatter results in poor part surface finish, damaged cutting tool, and an irritating and unacceptable noise. Exten¬sive research has been undertaken to study the mechanisms of chatter formation. Efforts have been also made to prevent the occurrence of chatter vibration. Even though some progress have been made, fundamental studies on the mechanics of metal cutting are necessary to achieve chatter free operation of CNC machine tools to maintain their smooth operating cycle. The same is also true for Vertical Machining Centres (VMC, which operate at high cutting speeds and are capable of offering high metal removal rates. The present work deals with the effect of work materials, cutting conditions and diameter of end mill cutters on the frequency-amplitude characteristics of chatter and on machined surface roughness. Vibration data were recorded using an experimental rig consisting of KISTLER 3-component dynamometer model 9257B, amplifier, scope meters and a PC.  Three different types of vibrations were observed. The first type was a low frequency vibration, associated with the interrupted nature of end mill operation. The second type of vibration was associated with the instability of the chip formation process and the third type was due to chatter. The frequency of the last type remained practically unchanged over a wide range of cutting speed.  It was further observed that chip-tool contact processes had considerable effect on the roughness of the machined surface.Key Words: Chatter, Cutting Conditions, Stable Cutting, Surface Roughness.

Gradient Boosting Machines, A Tutorial

Directory of Open Access Journals (Sweden)

Alexey eNatekin

2013-12-01

Full Text Available Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods. A theoretical information is complemented with many descriptive examples and illustrations which cover all the stages of the gradient boosting model design. Considerations on handling the model complexity are discussed. A set of practical examples of gradient boosting applications are presented and comprehensively analyzed.

Chování "Mid Spatial Frequencies" při CNC opracování optických ploch

Czech Academy of Sciences Publication Activity Database

Procháska, František; Matoušek, Ondřej; Psota, Pavel; Beneš, Jiří

2015-01-01

Roč. 60, č. 10 (2015), s. 293-295 ISSN 0447-6441 R&D Projects: GA MŠk(CZ) LO1206; GA TA ČR(CZ) TA03010843 Institutional support: RVO:61389021 Keywords : Mid Spatial Frequencies * CNC optical surface processing Subject RIV: JP - Industrial Processing

Key Elements of the Tutorial Support Management Model

Science.gov (United States)

Lynch, Grace; Paasuke, Philip

2011-01-01

In response to an exponential growth in enrolments the "Tutorial Support Management" (TSM) model has been adopted by Open Universities Australia (OUA) after a two-year project on the provision of online tutor support in first year, online undergraduate units. The essential focus of the TSM model was the development of a systemic approach…

An Evaluation of a Biological Slide-Tutorial Program.

Science.gov (United States)

Chan, Gordon L.

Described is an auto-tutorial slide program for zoology students. A self-paced system was devised for observing the subject matter covered in the twelve study units of a zoology course. The post-testing evaluation revealed that students with lower grade point averages achieved scores comparable with students of higher grade point averages.…

LHC@home online tutorial for Linux users - recording

CERN Multimedia

CERN. Geneva

2016-01-01

A step-by-step online tutorial for LHC@home by Karolina Bozek It contains detailed instructions for Linux users on how-to-join this volunteer computing project.  This 5' linked from http://lhcathome.web.cern.ch/join-us CLICK Here to see the commands to copy/paste for installing BOINC and the VirtualBox.

How Levels of Interactivity in Tutorials Affect Students' Learning of Modeling Transportation Problems in a Spreadsheet

Science.gov (United States)

Seal, Kala Chand; Przasnyski, Zbigniew H.; Leon, Linda A.

2010-01-01

Do students learn to model OR/MS problems better by using computer-based interactive tutorials and, if so, does increased interactivity in the tutorials lead to better learning? In order to determine the effect of different levels of interactivity on student learning, we used screen capture technology to design interactive support materials for…

VOLUMETRIC ERROR COMPENSATION IN FIVE-AXIS CNC MACHINING CENTER THROUGH KINEMATICS MODELING OF GEOMETRIC ERROR

Directory of Open Access Journals (Sweden)

Pooyan Vahidi Pashsaki

2016-06-01

Full Text Available Accuracy of a five-axis CNC machine tool is affected by a vast number of error sources. This paper investigates volumetric error modeling and its compensation to the basis for creation of new tool path for improvement of work pieces accuracy. The volumetric error model of a five-axis machine tool with the configuration RTTTR (tilting head B-axis and rotary table in work piece side A΄ was set up taking into consideration rigid body kinematics and homogeneous transformation matrix, in which 43 error components are included. Volumetric error comprises 43 error components that can separately reduce geometrical and dimensional accuracy of work pieces. The machining accuracy of work piece is guaranteed due to the position of the cutting tool center point (TCP relative to the work piece. The cutting tool is deviated from its ideal position relative to the work piece and machining error is experienced. For compensation process detection of the present tool path and analysis of the RTTTR five-axis CNC machine tools geometrical error, translating current position of component to compensated positions using the Kinematics error model, converting newly created component to new tool paths using the compensation algorithms and finally editing old G-codes using G-code generator algorithm have been employed.

Developing Parametric Models for the Assembly of Machine Fixtures for Virtual Multiaxial CNC Machining Centers

Science.gov (United States)

Balaykin, A. V.; Bezsonov, K. A.; Nekhoroshev, M. V.; Shulepov, A. P.

2018-01-01

This paper dwells upon a variance parameterization method. Variance or dimensional parameterization is based on sketching, with various parametric links superimposed on the sketch objects and user-imposed constraints in the form of an equation system that determines the parametric dependencies. This method is fully integrated in a top-down design methodology to enable the creation of multi-variant and flexible fixture assembly models, as all the modeling operations are hierarchically linked in the built tree. In this research the authors consider a parameterization method of machine tooling used for manufacturing parts using multiaxial CNC machining centers in the real manufacturing process. The developed method allows to significantly reduce tooling design time when making changes of a part’s geometric parameters. The method can also reduce time for designing and engineering preproduction, in particular, for development of control programs for CNC equipment and control and measuring machines, automate the release of design and engineering documentation. Variance parameterization helps to optimize construction of parts as well as machine tooling using integrated CAE systems. In the framework of this study, the authors demonstrate a comprehensive approach to parametric modeling of machine tooling in the CAD package used in the real manufacturing process of aircraft engines.

Text Mining for Information Systems Researchers: An Annotated Topic Modeling Tutorial

DEFF Research Database (Denmark)

Debortoli, Stefan; Müller, Oliver; Junglas, Iris

2016-01-01

, such as manual coding. Yet, the size of text data setsobtained from the Internet makes manual analysis virtually impossible. In this tutorial, we discuss the challengesencountered when applying automated text-mining techniques in information systems research. In particular, weshowcase the use of probabilistic...... researchers,this tutorial provides some guidance for conducting text mining studies on their own and for evaluating the quality ofothers.......t is estimated that more than 80 percent of today’s data is stored in unstructured form (e.g., text, audio, image, video);and much of it is expressed in rich and ambiguous natural language. Traditionally, the analysis of natural languagehas prompted the use of qualitative data analysis approaches...

A tutorial on Palm distributions for spatial point processes

DEFF Research Database (Denmark)

Coeurjolly, Jean-Francois; Møller, Jesper; Waagepetersen, Rasmus Plenge

2017-01-01

This tutorial provides an introduction to Palm distributions for spatial point processes. Initially, in the context of finite point processes, we give an explicit definition of Palm distributions in terms of their density functions. Then we review Palm distributions in the general case. Finally, we...

Assessment of concrete characteristics during the deliberate deformation of a flexible mould after casting

NARCIS (Netherlands)

Schipper, H.R.; Grunewald, S.; Troian, S.; Raghunath, P.; Schlangen, H.E.J.G.; Copuroglu, O.; Pecur, I.B.; Baricevic, A.; Stirmer, N; Bjegovic, D.

2017-01-01

Expensive CNC (computer numerical controlled)-milled formwork is required for the production of double-curved precast concrete elements for cladding or shell structures. The innovative flexible mould method for economically efficient and sustainable production of such elements, developed at Delft

Kine-Mould : Manufacturing technology for curved architectural elements in concrete

NARCIS (Netherlands)

Schipper, H.R.; Eigenraam, P.; Grünewald, S.; Soru, M.; Nap, P.; Van Overveld, B.; Vermeulen, J.

2015-01-01

The production of architectural elements with complex geometry is challenging for concrete manufacturers. Computer-numerically-controlled (CNC) milled foam moulds have been applied frequently in the last decades, resulting in good aesthetical performance. However, still the costs are high and a

Extensión del estándar ISO 10303 AP-238 para la automatización del acceso a datos de procesos CNC

Directory of Open Access Journals (Sweden)

J. Garrido

2009-01-01

Full Text Available Resumen: El nuevo estándar ISO 10303-AP238 (STEP-NC abre nuevas posibilidades para la comunicación de datos entre sistemas CAD/CAM y sistemas de fabricación CNC. Este artículo propone una extensión del modelo de información STEP-NC con nuevas estructuras de datos y nuevas funciones NC para contemplar capacidades de acceso a información en tiempo real del proceso de mecanizado, y apoyar a otras actividades avanzadas como la trazabilidad o la realización de los llamados procesos de mecanizado closed loop. Palabras Clave: Automatización, CAD/CAM, CNC, estándares, ISO, monitorizar, adquisición de datos

Efficacy of Multimedia Learning Modules as Preparation for Lecture-Based Tutorials in Electromagnetism

Directory of Open Access Journals (Sweden)

James Christopher Moore

2018-02-01

Full Text Available We have investigated the efficacy of on-line, multimedia learning modules (MLMs as preparation for in-class, lecture-based tutorials in electromagnetism in a physics course for natural science majors (biology and marine science. Specifically, we report the results of a multiple-group pre/post-test research design comparing two groups receiving different treatments with respect to activities preceding participation in Tutorials in Introductory Physics. The different pre-tutorial activities were as follows: (1 students were assigned reading from a traditional textbook, followed by a traditional lecture; and (2 students completed on-line MLMs developed by the Physics Education Research Group at the University of Illinois at Urbana Champaign (UIUC, and commercially known as FlipItPhysics. The MLM treatment group earned significantly higher mid-term examination scores and larger gains in content knowledge as measured by the Conceptual Survey of Electricity and Magnetism (CSEM. Student attitudes towards “reformed” instruction in the form of active-engagement tutorials were also improved. Specifically, post-course surveys showed that MLM-group students believed class time was more effective and the instructor was more clear than reported by non-MLM students, even though there was no significant difference between groups with respect to in-class activities and the same instructor taught both groups. MLM activities can be a highly effective tool for some student populations, especially when student preparation and buy-in are important for realizing significant gains.

Decontamination effect of milling by a jet mill on bacteria in rice flour.

Science.gov (United States)

Sotome, Itaru; Nei, Daisuke; Tsuda, Masuko; Mohammed, Sharif Hossen; Takenaka, Makiko; Okadome, Hiroshi; Isobe, Seiichiro

2011-06-01

The decontamination effect of milling by a jet mill was investigated by counting the number of bacteria in brown and white rice flour with mean particle diameters of 3, 20, and 40µm prepared by the jet mill. In the jet mill, the particles are crushed and reduced in size by the mechanical impact caused by their collision. Although the brown and white rice grains were contaminated with approximately 10(6) and 10(5) CFU/g bacteria, the microbial load of the rice flour decreased as the mean particle diameter decreased, ultimately decreasing to approximately 104 and 103 CFU/g in the brown and white rice flour. The temperature and pressure changes of the sample were not considered to have an effect on reducing the bacterial count during the milling. Hence, it was thought that the rice flour was decontaminated by other effects.

[The opinion of teachers about tutorial problem based learning].

Science.gov (United States)

Navarro H, Nancy; Zamora S, José

2014-08-01

In 2004 the Faculty of Medicine of Universidad de La Frontera in Chile implemented curricular changes, incorporating small group problem based learning in different carriers. To explore aspects that hamper or facilitate tutorial problem based learning from the perspective of tutors. Six in depth interviews and a focus group with tutors were carried out in 2010 and 2011. Data were analyzed through constant comparisons using the program ATLAS ti, guaranteeing credibility, reliance, validation and transferability. Five hundred and twenty eight (528) significance units were identified and 25 descriptive categories emerged. The categories of tutor motivation, methodological domain, tutor responsibility, tutor critical capacity, disciplinary domain, student participation and tutor-student interaction were emphasized. Three qualitative domains were generated, namely tutor skills, transformation of student roles and institutional commitment. Tutorial teaching is favored by teachers when the institutions train them in the subject, when there is administrative support and an adequate infrastructure and coordination.

Universal CNC platform motion control technology for industrial CT

International Nuclear Information System (INIS)

Cheng Senlin; Wang Yang

2011-01-01

According to the more scanning methods and the higher speed of industrial CT, the higher precision of the motion location and the data collection sync-control is required at present, a new motion control technology was proposed, which was established based on the universal CNC system with high precision of multi-axis control. Aiming at the second and the third generation of CT scanning motion, a control method was researched, and achieved the demands of the changeable parameters and network control, Through the simulation of the second and the third generation of CT scanning motion process, the control precision of the rotation axis reached 0.001° and the linear axis reached 0.002 mm, Practical tests showed this system can meet the requirements of the multi-axis motion integration and the sync signal control, it also have advantages in the control precision and the performance. (authors)

Hybrid ABC Optimized MARS-Based Modeling of the Milling Tool Wear from Milling Run Experimental Data

OpenAIRE

Garc?a Nieto, Paulino Jos?; Garc?a-Gonzalo, Esperanza; Ord??ez Gal?n, Celestino; Bernardo S?nchez, Antonio

2016-01-01

Milling cutters are important cutting tools used in milling machines to perform milling operations, which are prone to wear and subsequent failure. In this paper, a practical new hybrid model to predict the milling tool wear in a regular cut, as well as entry cut and exit cut, of a milling tool is proposed. The model was based on the optimization tool termed artificial bee colony (ABC) in combination with multivariate adaptive regression splines (MARS) technique. This optimization mechanism i...

Statistical Shape Modelling and Markov Random Field Restoration (invited tutorial and exercise)

DEFF Research Database (Denmark)

Hilger, Klaus Baggesen

This tutorial focuses on statistical shape analysis using point distribution models (PDM) which is widely used in modelling biological shape variability over a set of annotated training data. Furthermore, Active Shape Models (ASM) and Active Appearance Models (AAM) are based on PDMs and have proven...... deformation field between shapes. The tutorial demonstrates both generative active shape and appearance models, and MRF restoration on 3D polygonized surfaces. ''Exercise: Spectral-Spatial classification of multivariate images'' From annotated training data this exercise applies spatial image restoration...... using Markov random field relaxation of a spectral classifier. Keywords: the Ising model, the Potts model, stochastic sampling, discriminant analysis, expectation maximization....

The impact of maths support tutorials on mathematics confidence and academic performance in a cohort of HE Animal Science students.

Science.gov (United States)

van Veggel, Nieky; Amory, Jonathan

2014-01-01

Students embarking on a bioscience degree course, such as Animal Science, often do not have sufficient experience in mathematics. However, mathematics forms an essential and integral part of any bioscience degree and is essential to enhance employability. This paper presents the findings of a project looking at the effect of mathematics tutorials on a cohort of first year animal science and management students. The results of a questionnaire, focus group discussions and academic performance analysis indicate that small group tutorials enhance students' confidence in maths and improve students' academic performance. Furthermore, student feedback on the tutorial programme provides a deeper insight into student experiences and the value students assign to the tutorials.

Auto-Tutorial Instruction in Entomology: Principles of Entomology (Orders).

Science.gov (United States)

Minnick, D. R.; Steele, K. L.

Auto-tutorial instruction was compared to traditional lecture instruction in a university entomology course. In seven consecutive terms, undergraduate students enrolled in an introductory entomology course were divided into two groups: Group I received only lecture instruction on insect orders, while Group II was dismissed for three consecutive…

Tutorial : service-oriented architecture (SOA) development for serious games

NARCIS (Netherlands)

Carvalho, M.B.; Hu, J.; Bellotti, F.; de Gloria, A.; Rauterberg, G.W.M.; Chorianopoulos, K.; Divitini, M.; Hauge, J.; Jaccheri, L.; Malaka, R.

2015-01-01

This tutorial aims to introduce the benefits of applying a service-oriented architecture (SOA) approach to serious games developers. For that end, we propose a hands-on session in which we will provide information on state-of-the-art services for serious games and guide developers in rethinking one

Perancangan Coupled Fuzzy Logic Controller pada Prototipe Mesin Computer Numerical Control (CNC

Directory of Open Access Journals (Sweden)

Nabilla Gustiviana

2012-09-01

Full Text Available Tingkat ketelitian mesin CNC dalam membuat suatu kontur merupakan hal yang penting. Adanya gesekan antara mata pahat dengan benda kerja saat melakukan gerakan feeding dalam membentuk suatu kontur dapat berakibat pada kesalahan bentuk kontur yang akan dihasilkan apabila di tiap sumbunya dikontrol secara individu. Untuk mengatasi permasalahan tersebut, maka dirancang kombinasi antara Fuzzy Logic Controller sebagai kontroler individu yang mengatasi permasalahan di tiap sumbu, dengan kontroler koordinasi, yaitu Cross-Coupled Controller. Algoritma dari kontroler ini dibuat dengan menggunakan software LabView 8.6. Hasil simulasi menunjukkan bahwa dengan menambahkan kontroler koordinasi, dapat memperbaiki nilai indeks performansi sebesar 37,5% untuk kontur linier dan 2,78% untuk kontur lingkaran

Tutorial on nonlinear backstepping: Applications to ship control

Directory of Open Access Journals (Sweden)

Thor I. Fossen

1999-04-01

Full Text Available The theoretical foundation of nonlinear backstepping designs is presented in a tutorial setting. This includes a brief review of integral backstepping, extensions to SISO and MIMO systems in strict feedback form and physical motivated case studies. Parallels and differences to feedback linearization where it is shown how so-called "good nonlincarities" can be exploited in the design are also made.

Beneficial uses of paper mill residuals for New York State`s recycled-paper mills. Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

This report evaluates the New York paper mill industry in terms of the productive management and treatment of solid wastes. It identifies current efforts by recycling mills to beneficially use paper mill residuals (often called sludge) and suggests additional options that should be considered by the industry in general and individual mills in particular. It also examines the regulations and economics affecting the mills and suggests actions that could improve the industry`s ability to convert wastes to value-added products. The report recommends that the mills should continue measures to reduce fiber and filler clay losses, promote the transfer of usable fiber and clay to mills able to use them, upgrade sludge dewatering capabilities, and take a more regional approach to solid waste disposal problems. State agencies are urged to support these efforts, encourage the development and commercialization of new beneficial use technologies, and reduce regulatory barriers whenever possible.

Dust Creation in CNC Drilling of Wood Composites

Directory of Open Access Journals (Sweden)

Tomasz Rogoziński

2015-04-01

Full Text Available This paper presents the particle-size distribution of dust created by the drilling of selected wood composites, which was carried out using a CNC machine. The particle-size distribution was studied through two methods. Two analyses were performed: the sieve analysis of samples from the whole mass of collected dust and the laser diffraction analysis of the finest fraction isolated by sieving. The results presented general information about the particle-size distribution of the dust, as well as detailed information on the content of the finest particles. This information revealed that the particles might pose a potential risk to the health of workers employed in the woodworking industry. This potential risk is due to the possibility of their dispersion in the atmosphere surrounding the workplace and their size, which allows them to be respirable. The relationship between the fineness of the dust and the type of wood composite was also tested. Most ultrafine particles are formed during the drilling of fibreboards and are especially produced in traditional wet technology.

Computer numerically controlled (CNC) aspheric shaping with toroidal Wheels (Abstract Only)

Science.gov (United States)

Ketelsen, D.; Kittrell, W. C.; Kuhn, W. M.; Parks, R. E.; Lamb, George L.; Baker, Lynn

1987-01-01

Contouring with computer numerically controlled (CNC) machines can be accomplished with several different tool geometries and coordinated machine axes. To minimize the number of coordinated axes for nonsymmetric work to three, it is common practice to use a spherically shaped tool such as a ball-end mill. However, to minimize grooving due to the feed and ball radius, it is desirable to use a long ball radius, but there is clearly a practical limit to ball diameter with the spherical tool. We have found that the use of commercially available toroidal wheels permits long effective cutting radii, which in turn improve finish and minimize grooving for a set feed. In addition, toroidal wheels are easier than spherical wheels to center accurately. Cutting parameters are also easier to control because the feed rate past the tool does not change as the slope of the work changes. The drawback to the toroidal wheel is the more complex calculation of the tool path. Of course, once the algorithm is worked out, the tool path is as easily calculated as for a spherical tool. We have performed two experiments with the Large Optical Generator (LOG) that were ideally suited to three-axis contouring--surfaces that have no axis of rotational symmetry. By oscillating the cutting head horizontally or vertically (in addition to the motions required to generate the power of the surface) , and carefully coordinating those motions with table rotation, the mostly astigmatic departure for these surfaces is produced. The first experiment was a pair of reflector molds that together correct the spherical aberration of the Arecibo radio telescope. The larger of these was 5 m in diameter and had a 12 cm departure from the best-fit sphere. The second experiment was the generation of a purely astigmatic surface to demonstrate the feasibility of producing axially symmetric asphe.rics while mounted and rotated about any off-axis point. Measurements of the latter (the first experiment had relatively

The acquisition and retention of ECG interpretation skills after a standardized web-based ECG tutorial

DEFF Research Database (Denmark)

Rolskov Bojsen, Signe; Räder, Sune Bernd Emil Werner; Holst, Anders Gaardsdal

2015-01-01

BACKGROUND: Electrocardiogram (ECG) interpretation is of great importance for patient management. However, medical students frequently lack proficiency in ECG interpretation and rate their ECG training as inadequate. Our aim was to examine the effect of a standalone web-based ECG tutorial...... and to assess the retention of skills using multiple follow-up intervals. METHODS: 203 medical students were included in the study. All participants completed a pre-test, an ECG tutorial, and a post-test. The participants were also randomised to complete a retention-test after short (2-4 weeks), medium (10.......6), respectively). When comparing the pre-test to retention-test delta scores, junior students had learned significantly more than senior students (junior students improved 10.7 points and senior students improved 4.7 points, p = 0.003). CONCLUSION: A standalone web-based ECG tutorial can be an effective means...

Tutorial: Assessment and Analysis of Polysyllables in Young Children

Science.gov (United States)

Masso, Sarah; McLeod, Sharynne; Baker, Elise

2018-01-01

Purpose: Polysyllables, words of 3 or more syllables, represent almost 30% of words used in American English. The purpose of this tutorial is to support speech-language pathologists' (SLPs') assessment and analysis of polysyllables, extending the focus of published assessment tools that focus on sampling and analyzing children's segmental accuracy…

New developments in surface technology and prototyping

Science.gov (United States)

Himmer, Thomas; Beyer, Eckhard

2003-03-01

Novel lightweight applications in the automotive and aircraft industries require advanced materials and techniques for surface protection as well as direct and rapid manufacturing of the related components and tools. The manufacturing processes presented in this paper are based on multiple additive and subtractive technologies such as laser cutting, laser welding, direct laser metal deposition, laser/plasma hybrid spraying technique or CNC milling. The process chain is similar to layer-based Rapid Prototyping Techniques. In the first step, the 3D CAD geometry is sliced into layers by a specially developed software. These slices are cut by high speed laser cutting and then joined together. In this way laminated tools or parts are built. To improve surface quality and to increase wear resistance a CNC machining center is used. The system consists of a CNC milling machine, in which a 3 kW Nd:YAG laser, a coaxial powder nozzle and a digitizing system are integrated. Using a new laser/plasma hybrid spraying technique, coatings can be deposited onto parts for surface protection. The layers show a low porosity and high adhesion strength, the thickness is up to 0.3 mm, and the lower effort for preliminary surface preparation reduces time and costs of the whole process.

Characterizing representational learning: A combined simulation and tutorial on perturbation theory

Directory of Open Access Journals (Sweden)

Antje Kohnle

2017-11-01

Full Text Available Analyzing, constructing, and translating between graphical, pictorial, and mathematical representations of physics ideas and reasoning flexibly through them (“representational competence” is a key characteristic of expertise in physics but is a challenge for learners to develop. Interactive computer simulations and University of Washington style tutorials both have affordances to support representational learning. This article describes work to characterize students’ spontaneous use of representations before and after working with a combined simulation and tutorial on first-order energy corrections in the context of quantum-mechanical time-independent perturbation theory. Data were collected from two institutions using pre-, mid-, and post-tests to assess short- and long-term gains. A representational competence level framework was adapted to devise level descriptors for the assessment items. The results indicate an increase in the number of representations used by students and the consistency between them following the combined simulation tutorial. The distributions of representational competence levels suggest a shift from perceptual to semantic use of representations based on their underlying meaning. In terms of activity design, this study illustrates the need to support students in making sense of the representations shown in a simulation and in learning to choose the most appropriate representation for a given task. In terms of characterizing representational abilities, this study illustrates the usefulness of a framework focusing on perceptual, syntactic, and semantic use of representations.

Characterizing representational learning: A combined simulation and tutorial on perturbation theory

Science.gov (United States)

Kohnle, Antje; Passante, Gina

2017-12-01

Analyzing, constructing, and translating between graphical, pictorial, and mathematical representations of physics ideas and reasoning flexibly through them ("representational competence") is a key characteristic of expertise in physics but is a challenge for learners to develop. Interactive computer simulations and University of Washington style tutorials both have affordances to support representational learning. This article describes work to characterize students' spontaneous use of representations before and after working with a combined simulation and tutorial on first-order energy corrections in the context of quantum-mechanical time-independent perturbation theory. Data were collected from two institutions using pre-, mid-, and post-tests to assess short- and long-term gains. A representational competence level framework was adapted to devise level descriptors for the assessment items. The results indicate an increase in the number of representations used by students and the consistency between them following the combined simulation tutorial. The distributions of representational competence levels suggest a shift from perceptual to semantic use of representations based on their underlying meaning. In terms of activity design, this study illustrates the need to support students in making sense of the representations shown in a simulation and in learning to choose the most appropriate representation for a given task. In terms of characterizing representational abilities, this study illustrates the usefulness of a framework focusing on perceptual, syntactic, and semantic use of representations.

Maintaining Quality While Expanding Our Reach: Using Online Information Literacy Tutorials in the Sciences and Health Sciences

Directory of Open Access Journals (Sweden)

Talitha Rosa Matlin

2017-09-01

Full Text Available Abstract Objective – This article aims to assess student achievement of higher-order information literacy learning outcomes from online tutorials as compared to in-person instruction in science and health science courses. Methods – Information literacy instruction via online tutorials or an in-person one-shot session was implemented in multiple sections of a biology (n=100 and a kinesiology course (n=54. After instruction, students in both instructional environments completed an identical library assignment to measure the achievement of higher-order learning outcomes and an anonymous student survey to measure the student experience of instruction. Results – The data collected from library assignments revealed no statistically significant differences between the two instructional groups in total assignment scores or scores on specific questions related to higher-order learning outcomes. Student survey results indicated the student experience is comparable between instruction groups in terms of clarity of instruction, student confidence in completing the course assignment after library instruction, and comfort in asking a librarian for help after instruction. Conclusions – This study demonstrates that it is possible to replace one-shot information literacy instruction sessions with asynchronous online tutorials with no significant reduction in student learning in undergraduate science and health science courses. Replacing in-person instruction with online tutorials will allow librarians at this university to reach a greater number of students and maintain contact with certain courses that are transitioning to completely online environments. While the creation of online tutorials is initially time-intensive, over time implementing online instruction could free up librarian time to allow for the strategic integration of information literacy instruction into other courses. Additional time savings could be realized by incorporating auto

TUTORIAL COACHING AS A STRATEGY OF PROFESSIONAL AND PERSONAL DEVELOPMENT: AN EXPERIENCE-BASED STUDY IN A SECONDARY EDUCATION INSTITUTE

Directory of Open Access Journals (Sweden)

GLADYS IBETH ARIZA ORDÓÑEZ

2005-01-01

Full Text Available Tutorial accompaniment constitutes at present a necessary alternative in the framework of higher education. This workstarts with a general conceptualization of the tutorial, and makes a review of the styles, methods and proceduresrelated to this academic life facet which can effectively contribute to reach the goals the present higher education pursuitwhen it is applied in a coherent and systematic way.Considering the changes that the economy as well as the legislation have generated in education, and mainly in thoseLatin-American university programs, it is necessary to generate changing processes on the curriculum conceptualization,the teaching activities and the academic planning, and also to promote tutorial programs to the students, in order torespond to the difficulties they confront along the different stages of their lives. This research emerges from the onecarried out about the effectiveness of a tutorial program at a Psychology Department. It pretends to highlight theprincipal points of the accompaniment tutorial programs that require to be adjusted and adapted, in order to facilitatean educational service aimed to consider not only the professional training but the personal formation as well.

Medical student perceptions of factors affecting productivity of problem-based learning tutorial groups: does culture influence the outcome?

Science.gov (United States)

Das Carlo, Mandira; Swadi, Harith; Mpofu, Debbie

2003-01-01

The popularization of problem-based learning (PBL) has drawn attention to the motivational and cognitive skills necessary for medical students in group learning. This study identifies the effect of motivational and cognitive factors on group productivity of PBL tutorial groups. A self-administered questionnaire was completed by 115 students at the end of PBL tutorials for 4 themes. The questionnaire explored student perceptions about effect of motivation, cohesion, sponging, withdrawal, interaction, and elaboration on group productivity. We further analyzed (a) differences in perceptions between male and female students, (b) effect of "problems," and (c) effect of student progress over time on group productivity. There were linear relations between a tutorial group's success and the factors studied. Significant differences were noted between male and female student groups. Students and tutors need to recognize symptoms of ineffective PBL groups. Our study emphasizes the need to take into account cultural issues in setting ground rules for PBL tutorials.

Static/dynamic Analysis and Optimization of Z-axis Stand of PCB CNC Drilling Machine*

Directory of Open Access Journals (Sweden)

Zhou Yanjun

2016-01-01

Full Text Available The finite element analysis is used for the static and dynamic analysis of the Z axis brace of PCB CNC drilling machine. With its results of maximum displacement deformation and von Mises stress and modal frequency, the defect of original design was found out. On such bases, a variety of optimization scheme is put forward and the best size of the Z axis brace is obtained by the performance comparison of the schemes. This method offers bases for the design and renovation of other machine tool components.

Double-curved precast concrete elements : Research into technical viability of the flexible mould method

NARCIS (Netherlands)

Schipper, H.R.

2015-01-01

The production of precast, concrete elements with complex, double-curved geometry is expensive due to the high costcosts of the necessary moulds and the limited possibilities for mould reuse. Currently, CNC-milled foam moulds are the solution applied mostly in projects, offering good aesthetic

PD Lab

NARCIS (Netherlands)

Bilow, Marcel; Entrop, Alexis Gerardus; Lichtenberg, Jos; Stoutjesdijk, Pieter

2015-01-01

PD Lab explores the applications of building sector related product development. PD lab investigates and tests digital production technologies like CNC milled wood connections. It will also act as a platform in its wider meaning to investigate the effects and influences of file to factory

Airborne effluent control at uranium mills

International Nuclear Information System (INIS)

Sears, M.B.

1976-01-01

The Oak Ridge National Laboratory has made an engineering cost--environmental benefit study of radioactive waste treatment systems for decreasing the amount of radioactive materials released from uranium ore processing mills. This paper summarizes the results of the study which pertain to the control and/or abatement of airborne radioactive materials from the mill processes. The tailings area is not included. Present practices in the uranium milling industry, with particular emphasis on effluent control and waste management, have been surveyed. A questionnaire was distributed to each active mill in the United States. Replies were received from about 75 percent of the mill operators. Visits were made to six operating uranium mills that were selected because they represented the different processes in use today and the newest, most modern in mill designs. Discussions were held with members of the Region IV Office of NRC and the Grand Junction Office of ERDA. Nuclear Science Abstracts, as well as other sources, were searched for literature pertinent to uranium mill processes, effluent control, and waste management

FM Interviews: Stephanie Mills

OpenAIRE

Valauskas, Edward

2002-01-01

Stephanie Mills is an author, editor, lecturer and ecological activist who has concerned herself with the fate of the earth and humanity since 1969, when her commencement address at Mills College in Oakland, Calif., drew the attention of a nation. Her speech, which the New York Times called "perhaps the most anguished statement" of the year's crop of valedictory speeches, predicted a bleak future. According to Mills, humanity was destined for suicide, the result of overpopulation and overuse ...

LHC@home online tutorial for Mac users - recording

CERN Multimedia

CERN. Geneva

2016-01-01

A step-by-step online tutorial about LHC@home for Mac users by Alexandre Racine. It contains detailed instructions on how-to-join this volunteer computing project.  There are 3 screen capture videos with the real installation process accelerated attached to the event page. This 5' video is linked from http://lhcathome.web.cern.ch/join-us Also from the CDS e-learning category.

Rough mill simulator version 3.0: an analysis tool for refining rough mill operations

Science.gov (United States)

Edward Thomas; Joel Weiss

2006-01-01

ROMI-3 is a rough mill computer simulation package designed to be used by both rip-first and chop-first rough mill operators and researchers. ROMI-3 allows users to model and examine the complex relationships among cutting bill, lumber grade mix, processing options, and their impact on rough mill yield and efficiency. Integrated into the ROMI-3 software is a new least-...

TUTORIALS AS A STRATEGY TO STRENGTHEN THE UPPER LEVEL

Directory of Open Access Journals (Sweden)

Francisco Antonio Romero-Leyva

2014-01-01

Full Text Available In the University context tutorials are displayed as a strategy for improving the quality of higher education, therefore the Universidad de Occidente in its educational model has incorporated this program; on the basis of the above it is interesting to perform an analysis and proposal to improve the institutional program of mentoring (PIT of the U de O, El Fuerte unit. The objective of this research was an analysis of the institutional program of tutoring from the Universidad de Occidente, El Fuerte unit and propose suggestions for improvements. The deductive-inductive method was used, non-probability sampling, with a representative sample of 10% of the universe, the techniques applied the questionnaire and the interview. The sources consulted were; personal, institutional, electronic sources and documentary Among the outstanding results include that it is essential that the IES put in place tutorial systems through which students have to throughout their training with the advice and support of a teacher properly prepared, the way how they are implemented is commitment of each institution, in El Fuerte Unit is necessary training quarterly to the body of tutors, have comfortable spaces for the tutorial process, the administrative authorities require compliance with the listing because it allows the tutor to better control and management problems of their tutees, having the program strategies to rescue students who for various reasons leave the classrooms of the University; this program being a tool to comply with Tutoring System, thereby obtaining increased rates and terminal efficiency and comply graduate profile al. As tutors we need to reflect critically on our personal and professional performance when interacting with tutees, to promote change and the process of development of human potential performance.

Investigating Learning with an Interactive Tutorial: A Mixed-Methods Strategy

Science.gov (United States)

de Villiers, M. R.; Becker, Daphne

2017-01-01

From the perspective of parallel mixed-methods research, this paper describes interactivity research that employed usability-testing technology to analyse cognitive learning processes; personal learning styles and times; and errors-and-recovery of learners using an interactive e-learning tutorial called "Relations." "Relations"…

Effect of Tutorial Mode of Computer-Assisted Instruction on Students ...

African Journals Online (AJOL)

This study investigated the effect of Tutorial Mode of Computer- Assisted Instruction (CAI) on students' academic performance in practical geography in Nigeria, However, the sample population of eighty (80) Senior Secondary School Two geography students that were randomly selected from two privately owned secondary ...

Tutorial: Calculating Percentile Rank and Percentile Norms Using SPSS

Science.gov (United States)

Baumgartner, Ted A.

2009-01-01

Practitioners can benefit from using norms, but they often have to develop their own percentile rank and percentile norms. This article is a tutorial on how to quickly and easily calculate percentile rank and percentile norms using SPSS, and this information is presented for a data set. Some issues in calculating percentile rank and percentile…

Advanced CNC and CAM Series. Educational Resources for the Machine Tool Industry. Course Syllabi, Instructor's Handbook [and] Student Laboratory Manual.

Science.gov (United States)

Texas State Technical Coll. System, Waco.

This package consists of course syllabi, an instructor's handbook, and student laboratory manual for a 1-year vocational training program to prepare students for entry-level positions as advanced computer numerical control (CNC) and computer-assisted manufacturing (CAM) technicians.. The program was developed through a modification of the DACUM…

Hybrid ABC Optimized MARS-Based Modeling of the Milling Tool Wear from Milling Run Experimental Data.

Science.gov (United States)

García Nieto, Paulino José; García-Gonzalo, Esperanza; Ordóñez Galán, Celestino; Bernardo Sánchez, Antonio

2016-01-28

Milling cutters are important cutting tools used in milling machines to perform milling operations, which are prone to wear and subsequent failure. In this paper, a practical new hybrid model to predict the milling tool wear in a regular cut, as well as entry cut and exit cut, of a milling tool is proposed. The model was based on the optimization tool termed artificial bee colony (ABC) in combination with multivariate adaptive regression splines (MARS) technique. This optimization mechanism involved the parameter setting in the MARS training procedure, which significantly influences the regression accuracy. Therefore, an ABC-MARS-based model was successfully used here to predict the milling tool flank wear (output variable) as a function of the following input variables: the time duration of experiment, depth of cut, feed, type of material, etc . Regression with optimal hyperparameters was performed and a determination coefficient of 0.94 was obtained. The ABC-MARS-based model's goodness of fit to experimental data confirmed the good performance of this model. This new model also allowed us to ascertain the most influential parameters on the milling tool flank wear with a view to proposing milling machine's improvements. Finally, conclusions of this study are exposed.

Hybrid ABC Optimized MARS-Based Modeling of the Milling Tool Wear from Milling Run Experimental Data

Directory of Open Access Journals (Sweden)

Paulino José García Nieto

2016-01-01

Full Text Available Milling cutters are important cutting tools used in milling machines to perform milling operations, which are prone to wear and subsequent failure. In this paper, a practical new hybrid model to predict the milling tool wear in a regular cut, as well as entry cut and exit cut, of a milling tool is proposed. The model was based on the optimization tool termed artificial bee colony (ABC in combination with multivariate adaptive regression splines (MARS technique. This optimization mechanism involved the parameter setting in the MARS training procedure, which significantly influences the regression accuracy. Therefore, an ABC–MARS-based model was successfully used here to predict the milling tool flank wear (output variable as a function of the following input variables: the time duration of experiment, depth of cut, feed, type of material, etc. Regression with optimal hyperparameters was performed and a determination coefficient of 0.94 was obtained. The ABC–MARS-based model's goodness of fit to experimental data confirmed the good performance of this model. This new model also allowed us to ascertain the most influential parameters on the milling tool flank wear with a view to proposing milling machine's improvements. Finally, conclusions of this study are exposed.

Hybrid ABC Optimized MARS-Based Modeling of the Milling Tool Wear from Milling Run Experimental Data

Science.gov (United States)

García Nieto, Paulino José; García-Gonzalo, Esperanza; Ordóñez Galán, Celestino; Bernardo Sánchez, Antonio

2016-01-01

Milling cutters are important cutting tools used in milling machines to perform milling operations, which are prone to wear and subsequent failure. In this paper, a practical new hybrid model to predict the milling tool wear in a regular cut, as well as entry cut and exit cut, of a milling tool is proposed. The model was based on the optimization tool termed artificial bee colony (ABC) in combination with multivariate adaptive regression splines (MARS) technique. This optimization mechanism involved the parameter setting in the MARS training procedure, which significantly influences the regression accuracy. Therefore, an ABC–MARS-based model was successfully used here to predict the milling tool flank wear (output variable) as a function of the following input variables: the time duration of experiment, depth of cut, feed, type of material, etc. Regression with optimal hyperparameters was performed and a determination coefficient of 0.94 was obtained. The ABC–MARS-based model's goodness of fit to experimental data confirmed the good performance of this model. This new model also allowed us to ascertain the most influential parameters on the milling tool flank wear with a view to proposing milling machine's improvements. Finally, conclusions of this study are exposed. PMID:28787882

Redesigning nursing tutorials for ESL students: a pilot study.

Science.gov (United States)

San Miguel, Caroline; Townsend, Lisa; Waters, Cheryl

2013-04-01

Increased enrolments of Bachelor of Nursing (BN) students who speak English as a second language (ESL) can help create a multilingual and culturally diverse workforce that is better prepared to meet the needs of increasingly diverse health populations. However, although ESL enrolments are increasing, attrition rates for ESL students tend to be higher than those of native speakers of English, partly due to academic failure. At the same time, concerns have been expressed in some quarters about the low levels of English language of entering students. As it is unlikely that language entry levels to university will be raised, sustainable programmes that help ESL students better meet the academic challenges they may face need to be developed. So far, models of ESL support have been mostly an adjunct to their degree, voluntary and not well attended. This paper discusses a model using tutorials integrated into the first year nursing curriculum that were specifically designed for ESL students with low levels of English language proficiency. The paper also examines students' perceptions of such tutorials, which they found beneficial to their learning.

Effect of milling time on microstructure and properties of Nano-titanium polymer by high-energy ball milling

Science.gov (United States)

Wang, Bo; Wei, Shicheng; Wang, Yujiang; Liang, Yi; Guo, Lei; Xue, Junfeng; Pan, Fusheng; Tang, Aitao; Chen, Xianhua; Xu, Binshi

2018-03-01

Nano-titanium (Nano-Ti) was prepared by high-energy ball milling from pure Ti power and grinding agents (Epoxy resin) at room temperature. The effect of milling time on structure and properties of Nano-Ti polymer were investigated systematically. The results show that high-energy ball milling is an effective way to produce Nano-Ti polymer. The dispersion stability and compatibility between Ti power and grinding agents are improved by prolonging the milling time at a certain degree, that is to say, the optimization milling time is 240 min. The particle size of Ti powder and the diffraction peaks intensity of Ti decrease obviously as the milling time increases due to the compression stress, shear friction and other mechanical forces are formed during ball milling. FT-IR result displays that the wavenumber of all the bands move to lower wavenumber after ball milling, and the epoxy ring is open. The system internal energy rises owing to the broken epoxy group and much more Nano-Ti is formed to promote the grafting reaction between Nano-Ti and epoxy resin. The results from TEM and XPS also prove that. And the grafting ration is maximum as the milling time is 240 min, the mass loss ratio is 17.53%.

A Design of Computer Aided Instructions (CAI) for Undirected Graphs in the Discrete Math Tutorial (DMT). Part 1.

Science.gov (United States)

1990-06-01

The objective of this thesis research is to create a tutorial for teaching aspects of undirected graphs in discrete math . It is one of the submodules...of the Discrete Math Tutorial (DMT), which is a Computer Aided Instructional (CAI) tool for teaching discrete math to the Naval Academy and the

A Design of Computer Aided Instructions (CAI) for Undirected Graphs in the Discrete Math Tutorial (DMT). Part 2

Science.gov (United States)

1990-06-01

The objective of this thesis research is to create a tutorial for teaching aspects of undirected graphs in discrete math . It is one of the submodules...of the Discrete Math Tutorial (DMT), which is a Computer Aided Instructional (CAI) tool for teaching discrete math to the Naval Academy and the

Interactive video tutorials for enhancing problem solving, reasoning, and meta-cognitive skills of introductory physics students

OpenAIRE

Singh, Chandralekha

2016-01-01

We discuss the development of interactive video tutorial-based problems to help introductory physics students learn effective problem solving heuristics. The video tutorials present problem solving strategies using concrete examples in an interactive environment. They force students to follow a systematic approach to problem solving and students are required to solve sub-problems (research-guided multiple choice questions) to show their level of understanding at every stage of prob lem solvin...

A broadcast engineering tutorial for non-engineers

CERN Document Server

Pizzi, Skip

2014-01-01

A Broadcast Engineering Tutorial for Non-Engineers is the leading publication on the basics of broadcast technology. Whether you are new to the industry or do not have an engineering background, this book will give you a comprehensive primer of television, radio, and digital media relating to broadcast-it is your guide to understanding the technical world of radio and television broadcast engineering. It covers all the important topics such as DTV, IBOC, HD, standards, video servers, editing, electronic newsrooms, and more.

Focused ion beam milling of carbon fibres

International Nuclear Information System (INIS)

Huson, Mickey G.; Church, Jeffrey S.; Hillbrick, Linda K.; Woodhead, Andrea L.; Sridhar, Manoj; Van De Meene, Allison M.L.

2015-01-01

A focused ion beam has been used to mill both individual carbon fibres as well as fibres in an epoxy composite, with a view to preparing flat surfaces for nano-indentation. The milled surfaces have been assessed for damage using scanning probe microscopy nano-indentation and Raman micro-probe analysis, revealing that FIB milling damages the carbon fibre surface and covers surrounding areas with debris of disordered carbon. The debris is detected as far as 100 μm from the milling site. The energy of milling as well as the orientation of the beam was varied and shown to have an effect when assessed by Raman spectroscopy. - Highlights: • Focused ion beam (FIB) milling was used to mill flat surfaces on carbon fibres. • Raman spectroscopy showed amorphous carbon was generated during FIB milling. • The amorphous debris is detected as far as 100 μm from the milling site. • This surface degradation was confirmed by nano-indentation experiments.

A Study of Sustainable Assessment Theory in Higher Education Tutorials

Science.gov (United States)

Beck, Robert J.; Skinner, William F.; Schwabrow, Lynsey A.

2013-01-01

A study of sustainable assessment theory in nine tutorial courses at four colleges demonstrated that three long-term learning outcomes improved: Independence, Intellectual Maturity and Creativity. Eight of 10 traits associated with these outcomes were validated through internal reliability, faculty and student rubrics, and faculty case studies…

Sadhana | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Sadhana. SIBA SANKAR MAHAPATRA. Articles written in Sadhana. Volume 35 Issue 5 October 2010 pp 619-629. Optimization in CNC end milling of UNS C34000 medium leaded brass with multiple surface roughnesses characteristics · Bharat Chandra Routara Saumya Darsan Mohanty Saurav Datta ...

Sadhana | Indian Academy of Sciences

Indian Academy of Sciences (India)

Most wind tunnel models are fabricated of all metal components using computerized numerical control (CNC) milling machines. Fabrication of metal wind tunnel models is very expensive and time consuming. The models can require months to manufacture and are often made by small high technology companies that ...

Correction: A binary catalyst system of a cationic Ru-CNC pincer complex with an alkali metal salt for selective hydroboration of carbon dioxide.

Science.gov (United States)

Ng, Chee Koon; Wu, Jie; Hor, T S Andy; Luo, He-Kuan

2016-12-22

Correction for 'A binary catalyst system of a cationic Ru-CNC pincer complex with an alkali metal salt for selective hydroboration of carbon dioxide' by Chee Koon Ng et al., Chem. Commun., 2016, 52, 11842-11845.

La acción tutorial y el clima escolar en los centros de educación secundaria obligatoria

Directory of Open Access Journals (Sweden)

Cristiano Serrano García

2011-02-01

Full Text Available Con el presente estudio se pretende profundizar en cómo incide la Acción Tutorial en el Clima en los centros educativos públicos y concertados de Secundaria y las causas que el profesorado de estos centros señala como determinantes. La implantación de un Plan de Acción Tutorial lleva implícito una serie de dificultades y desafíos que conviene abordar desde una perspectiva realista y de futuro. El Plan de Acción Tutorial debe afrontar la adecuada organización y el buen funcionamiento de los centros, unidos a la participación positiva y a un clima motivador en el trabajo. Es interesante determinar cuáles son los elementos y factores en la Acción Tutorial y el Clima de, así como la relación existente entre ambos. El objetivo de este estudio es comprobar si, desde la Acción Tutorial se mejora la Ecología del Centro, se influye en la Dirección, se mejora la Cultura de Convivencia, se incide sobre el Sistema Social, se mejora el Desarrollo Profesional y se consigue la Satisfacción de los profesionales de ámbitos educativos, se puede mejorar el Clima Escolar como conjunto. Se trata de un estudio evaluativo, para ello se ha aplicado los cuestionarios a 187 profesores de diversos centros públicos y concertados de Secundaria, que conforma la muestra del estudio. Para finalizar es necesario señalar que: «Si desde la Acción Tutorial conseguimos aumentar la comunicación entre la comunidad educativa, aumentaremos la confianza, conseguiremos un alto grado de motivación y esto ayudará a conseguir una participación activa y facilitará la obtención de un mejor clima en el centro educativo».

Surface Quality of Staggered PCD End Mill in Milling of Carbon Fiber Reinforced Plastics

Directory of Open Access Journals (Sweden)

Guangjun Liu

2017-02-01

Full Text Available Machined surface quality determines the reliability, wear resistance and service life of carbon fiber reinforced plastic (CFRP workpieces. In this work, the formation mechanism of the surface topography and the machining defects of CFRPs are proposed, and the influence of milling parameters and fiber cutting angles on the surface quality of CFRPs is obtained, which can provide a reference for extended tool life and good surface quality. Trimming and slot milling tests of unidirectional CFRP laminates are performed. The surface roughness of the machined surface is measured, and the influence of milling parameters on the surface roughness is analyzed. A regression model for the surface roughness of CFRP milling is established. A significance test of the regression model is conducted. The machined surface topography of milling CFRP unidirectional laminates with different fiber orientations is analyzed, and the effect of fiber cutting angle on the surface topography of the machined surface is presented by using a digital super depth-of-field microscope and scanning electron microscope (SEM. To study the influence of fiber cutting angle on machining defects, the machined topography under different fiber orientations is analyzed. The slot milling defects and their formation mechanism under different fiber cutting angles are investigated.

Effectiveness of a computer-based tutorial for teaching how to make a blood smear.

Science.gov (United States)

Preast, Vanessa; Danielson, Jared; Bender, Holly; Bousson, Maury

2007-09-01

Computer-aided instruction (CAI) was developed to teach veterinary students how to make blood smears. This instruction was intended to replace the traditional instructional method in order to promote efficient use of faculty resources while maintaining learning outcomes and student satisfaction. The purpose of this study was to evaluate the effect of a computer-aided blood smear tutorial on 1) instructor's teaching time, 2) students' ability to make blood smears, and 3) students' ability to recognize smear quality. Three laboratory sessions for senior veterinary students were taught using traditional methods (control group) and 4 sessions were taught using the CAI tutorial (experimental group). Students in the control group received a short demonstration and lecture by the instructor at the beginning of the laboratory and then practiced making blood smears. Students in the experimental group received their instruction through the self-paced, multimedia tutorial on a laptop computer and then practiced making blood smears. Data was collected from observation, interview, survey questionnaires, and smear evaluation by students and experts using a scoring rubric. Students using the CAI made better smears and were better able to recognize smear quality. The average time the instructor spent in the room was not significantly different between groups, but the quality of the instructor time was improved with the experimental instruction. The tutorial implementation effectively provided students and instructors with a teaching and learning experience superior to the traditional method of instruction. Using CAI is a viable method of teaching students to make blood smears.

Difficult incidents and tutor interventions in problem-based learning tutorials.

Science.gov (United States)

Kindler, Pawel; Grant, Christopher; Kulla, Steven; Poole, Gary; Godolphin, William

2009-09-01

Tutors report difficult incidents and distressing conflicts that adversely affect learning in their problem-based learning (PBL) groups. Faculty development (training) and peer support should help them to manage this. Yet our understanding of these problems and how to deal with them often seems inadequate to help tutors. The aim of this study was to categorise difficult incidents and the interventions that skilled tutors used in response, and to determine the effectiveness of those responses. Thirty experienced and highly rated tutors in our Year 1 and 2 medical curriculum took part in semi-structured interviews to: identify and describe difficult incidents; describe how they responded, and assess the success of each response. Recorded and transcribed data were analysed thematically to develop typologies of difficult incidents and interventions and compare reported success or failure. The 94 reported difficult incidents belonged to the broad categories 'individual student' or 'group dynamics'. Tutors described 142 interventions in response to these difficult incidents, categorised as: (i) tutor intervenes during tutorial; (ii) tutor gives feedback outside tutorial, or (iii) student or group intervenes. Incidents in the 'individual student' category were addressed relatively unsuccessfully (effective 75% of the time) by response (iii). None of the interventions worked well when used in response to problems related to 'group dynamics'. Overall, 59% of the difficult incidents were dealt with successfully. Dysfunctional PBL groups can be highly challenging, even for experienced and skilled tutors. Within-tutorial feedback, the treatment that tutors are most frequently advised to apply, was often not effective. Our study suggests that the collective responsibility of the group, rather than of the tutor, to deal with these difficulties should be emphasised.

Yang-Mills gravity in biconformal space

International Nuclear Information System (INIS)

Anderson, Lara B; Wheeler, James T

2007-01-01

We write a gravity theory with Yang-Mills-type action using the biconformal gauging of the conformal group. We show that the resulting biconformal Yang-Mills gravity theories describe 4-dim, scale-invariant general relativity in the case of slowly changing fields. In addition, we systematically extend arbitrary 4-dim Yang-Mills theories to biconformal space, providing a new arena for studying flat-space Yang-Mills theories. By applying the biconformal extension to a 4-dim pure Yang-Mills theory with conformal symmetry, we establish a 1-1, onto mapping between a set of gravitational gauge theories and 4-dim, flat-space gauge theories

Implementation of Inquiry-Based Tutorials in AN Introductory Physics Course: the Role of the Graduate Teaching Assistant.

Science.gov (United States)

Thoresen, Carol Wiggins

1994-01-01

This study determined if the training provided physics teaching assistants was sufficient to accomplish the objectives of inquiry-based tutorials for an introductory physics course. Qualitative research methods were used: (1) to determine if the Physics by Inquiry method was modeled; (2) to describe the process from the teaching assistant perspective; (3) to determine TA opinions on training methods; (4) to develop a frame of reference to better understand the role of TA's as instructional support staff. The study determined that the teaching assistants verbalized appropriate instructional actions, but were observed to use a predominantly didactic teaching style. TA's held a variety of perceptions and beliefs about inquiry -based learning and how science is learned. They felt comfortable in the role of tutorial instructor. They were satisfied with the training methods provided and had few suggestions to change or improve training for future tutorial instructors. A concurrent theme of teacher action dependent on teacher beliefs was sustained throughout the study. The TA's actions, as tutorial instructors, reflected their educational beliefs, student background and learning experiences. TA's performance as tutorial instructors depended on what they think and believe about learning science. Practical implications exist for training teaching assistants to be tutorial instructors. Some recommendations may be appropriate for TA's required to use instructional methods that they have not experienced as students. Interview prospective teaching assistants to determine educational experience and beliefs. Employ inexperienced teaching assistants whose perspectives match the proposed instructional role and who might be more receptive to modeling. Incorporate training into staff meetings. Provide time for TA's to experience the instructional model with simulation or role play as students and as instructors, accompanied by conference discussion. Use strategies known to enhance

Tutorial review of spent-fuel degradation mechanisms under dry-storage conditions

International Nuclear Information System (INIS)

Einziger, R.E.

1983-02-01

This tutorial reviews our present understanding of fuel-rod degradation over a range of possible dry-storage environments. Three areas are covered: (1) why study fuel-rod degradation; (2) cladding-degradation mechanisms; and (3) the status of fuel-oxidation studies

Hyperspectral image analysis. A tutorial

DEFF Research Database (Denmark)

Amigo Rubio, Jose Manuel; Babamoradi, Hamid; Elcoroaristizabal Martin, Saioa

2015-01-01

This tutorial aims at providing guidelines and practical tools to assist with the analysis of hyperspectral images. Topics like hyperspectral image acquisition, image pre-processing, multivariate exploratory analysis, hyperspectral image resolution, classification and final digital image processi...... to differentiate between several types of plastics by using Near infrared hyperspectral imaging and Partial Least Squares - Discriminant Analysis. Thus, the reader is guided through every single step and oriented in order to adapt those strategies to the user's case....... will be exposed, and some guidelines given and discussed. Due to the broad character of current applications and the vast number of multivariate methods available, this paper has focused on an industrial chemical framework to explain, in a step-wise manner, how to develop a classification methodology...

Pengaturan Kecepatan Motor Spindle pada Retrofit Mesin Bubut CNC Menggunakan Kontroler PID Gain Scheduling

Directory of Open Access Journals (Sweden)

Fikri Yoga Permana

2013-03-01

Full Text Available Pada mesin bubut Computerized Numerical Control (CNC, proses pemahatan benda kerja memerlukan kecepatan potong yang tetap agar hasil kerja memiliki tingkat presisi tinggi. Dalam prakteknya, ketika terjadi pemotongan, diameter benda kerja akan selalu berkurang dan tingkat kedalaman pahat berubah-ubah sesuai dengan proses yang dilakukan sehingga mempengaruhi kecepatan putar motor spindle sehingga mengakibatkan tingkat presisi hasil kerja menjadi berkurang. Pada penelitian ini, digunakan kontroler PI Gain Scheduling untuk mengatur kecapatan motor spindle. Hasil yang didapatkan berupa simulasi kontroler PI Gain Scheduling. Dari hasil simulasi didapatkan kontroler PI Gain Scheduling mampu membuat respon sistem sesuai dengan yang diinginkan.

Influence of rice sample preparation and milling procedures on milling quality appraisals

Science.gov (United States)

The objective of this research was to investigate the effect of sample preparation and milling procedure on milling quality appraisals of rough rice. Samples of freshly harvested medium-grain rice (M202) with different initial moisture contents (MCs) ranging from 20.2% to 25.1% (w.b.) were used for...

Influence of milling process on efavirenz solubility

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Erizal Zaini

2017-01-01

Full Text Available Introduction: The aim of this study was to investigate the influence of the milling process on the solubility of efavirenz. Materials and Methods: Milling process was done using Nanomilling for 30, 60, and 180 min. Intact and milled efavirenz were characterized by powder X-ray diffraction, scanning electron microscopy (SEM, spectroscopy infrared (IR, differential scanning calorimetry (DSC, and solubility test. Results: The X-ray diffractogram showed a decline on peak intensity of milled efavirenz compared to intact efavirenz. The SEM graph depicted the change from crystalline to amorphous habit after milling process. The IR spectrum showed there was no difference between intact and milled efavirenz. Thermal analysis which performed by DSC showed a reduction on endothermic peak after milling process which related to decreasing of crystallinity. Solubility test of intact and milled efavirenz was conducted in distilled water free CO2with 0.25% sodium lauryl sulfate media and measured using high-performance liquid chromatography method with acetonitrile: distilled water (80:20 as mobile phases. The solubility was significantly increased (P < 0.05 after milling processes, which the intact efavirenz was 27.12 ± 2.05, while the milled efavirenz for 30, 60, and 180 min were 75.53 ± 1.59, 82.34 ± 1.23, and 104.75 ± 0.96 μg/mL, respectively. Conclusions: Based on the results, the solubility of efavirenz improved after milling process.

A tutorial on machine learning in educational science

OpenAIRE

Kidzinski, Lukasz; Giannakos, Michail; Sampson, Demetrios G.; Dillenbourg, Pierre

2015-01-01

Popularity of massive online open courses (MOOCs) allowed educational researchers to address problems which were not accessible few years ago. Although classical statistical techniques still apply, large datasets allow us to discover deeper patterns and to provide more accu-rate predictions of student’s behaviors and outcomes. The goal of this tutorial is to disseminate knowledge on elementary data analysis tools as well as facilitating simple practical data-analysis activities with the purpo...

Benefits from Taking a Private Tutorial Course for Exam Preparation?

DEFF Research Database (Denmark)

la Cour, Lisbeth; Milhøj, Anders

course in order to perform well at the exam but still more than 50 % of a cohort signs up for the courses. Our data come from the administrative systems at Copenhagen Business School and they are merged with survey data on student satisfaction and tutorial participation. Based on simple regression...

MATS--Management Accounting Tutorial System. Version 1.0. Project Documentation.

Science.gov (United States)

Wardle, Andrew; O'Connor, Rodric

The Management Accounting Tutorial System (MATS) is a management accounting database for a carpet manufacturing company. The system allows the display and output of monthly activities, and is intended to provide a means of illustrating the main topics of the second year management accounting course at Manchester University. The system itself…

MATS--Management Accounting Tutorial System. Version 1.0. User Guide.

Science.gov (United States)

Wardle, Andrew; O'Connor, Rodric

The Management Accounting Tutorial System (MATS) is a management accounting database for a carpet manufacturing company. The system allows the display and output of monthly activities, and is intended to provide a means of illustrating the main topics of the second year management accounting course at Manchester University. The system itself…

Particle deformation during stirred media milling

Science.gov (United States)

Hamey, Rhye Garrett

Production of high aspect ratio metal flakes is an important part of the paint and coating industry. The United States Army also uses high aspect ratio metal flakes of a specific dimension in obscurant clouds to attenuate infrared radiation. The most common method for their production is by milling a metal powder. Ductile metal particles are initially flattened in the process increasing the aspect ratio. As the process continues, coldwelding of metal flakes can take place increasing the particle size and decreasing the aspect ratio. Extended milling times may also result in fracture leading to a further decrease in the particle size and aspect ratio. Both the coldwelding of the particles and the breakage of the particles are ultimately detrimental to the materials performance. This study utilized characterization techniques, such as, light scattering and image analysis to determine the change in particle size as a function of milling time and parameters. This study proved that a fundamental relationship between the milling parameters and particle deformation could be established by using Hertz's theory to calculate the stress acting on the aluminum particles. The study also demonstrated a method by which milling efficiency could be calculated, based on the amount of energy required to cause particle deformation. The study found that the particle deformation process could be an energy efficient process at short milling times with milling efficiency as high as 80%. Finally, statistical design of experiment was used to obtain a model that related particle deformation to milling parameters, such as, rotation rate and milling media size.

Learning Activity Packets for Milling Machines. Unit I--Introduction to Milling Machines.

Science.gov (United States)

Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This learning activity packet (LAP) outlines the study activities and performance tasks covered in a related curriculum guide on milling machines. The course of study in this LAP is intended to help students learn to identify parts and attachments of vertical and horizontal milling machines, identify work-holding devices, state safety rules, and…

APLIKASI MOBILE LEARNING TUTORIAL PENGKABELAN DALAM MATA KULIAH JARINGAN KOMPUTER II DI STMIK AMIKOM PURWOKERTO

Directory of Open Access Journals (Sweden)

Tri Handoko

2011-02-01

Full Text Available Tujuan penelitian ini adalah membuat aplikasi mobile learning tutorial pengkabelan dalam mata kuliah jaringan komputer II di STMIK AMIKOM Purwokerto. Metode pengumpulan data yang digunakan untuk membuat aplikasi ini adalah metode kepustakaan dan metode observasi secara langsung. Untuk pengembangan sistem dalam penelitian ini menggunakan metode SDLC (System Development Life Cycle, dengan teknik pengembangan sistem waterfall model.Hasil penelitian ini berupa aplikasi mobile learning tutorial pengkabelan dalam mata kuliah jaringan komputer II di STMIK AMIKOM Purwokerto. Aplikasi yang dihasilkan berektensi .swf dan dapat dijalankan menggunakan flashlite player.

Object Oriented Approach for developing of a Tutorial System Work Security and Health in SMEs

Directory of Open Access Journals (Sweden)

2007-01-01

Full Text Available This paper presents the authors' research for developing a tutorial system which enables the delivery of proper training to specialized personnel in Small and Middle Enterprises (SMEs, in order to eliminate or reduce the health and safety risks of these enterprises to an acceptable level, according to the European Union directives. During the analysis phase, the requirements of the tutorial system were described using UML use case diagrams, the activity flow was modeled with an activity diagram, and the relevant classes were identified and described in a class diagram.

ANSYS workbench tutorial release 14 structural & thermal analysis using the ANSYS workbench release 14 environment

CERN Document Server

Lawrence, Kent L

2012-01-01

The exercises in ANSYS Workbench Tutorial Release 14 introduce you to effective engineering problem solving through the use of this powerful modeling, simulation and optimization software suite. Topics that are covered include solid modeling, stress analysis, conduction/convection heat transfer, thermal stress, vibration, elastic buckling and geometric/material nonlinearities. It is designed for practicing and student engineers alike and is suitable for use with an organized course of instruction or for self-study. The compact presentation includes just over 100 end-of-chapter problems covering all aspects of the tutorials.

Medical image reconstruction. A conceptual tutorial

International Nuclear Information System (INIS)

Zeng, Gengsheng Lawrence

2010-01-01

''Medical Image Reconstruction: A Conceptual Tutorial'' introduces the classical and modern image reconstruction technologies, such as two-dimensional (2D) parallel-beam and fan-beam imaging, three-dimensional (3D) parallel ray, parallel plane, and cone-beam imaging. This book presents both analytical and iterative methods of these technologies and their applications in X-ray CT (computed tomography), SPECT (single photon emission computed tomography), PET (positron emission tomography), and MRI (magnetic resonance imaging). Contemporary research results in exact region-of-interest (ROI) reconstruction with truncated projections, Katsevich's cone-beam filtered backprojection algorithm, and reconstruction with highly undersampled data with l 0 -minimization are also included. (orig.)

Charged particle beam current monitoring tutorial

International Nuclear Information System (INIS)

Webber, R.C.

1994-10-01

A tutorial presentation is made on topics related to the measurement of charged particle beam currents. The fundamental physics of electricity and magnetism pertinent to the problem is reviewed. The physics is presented with a stress on its interpretation from an electrical circuit theory point of view. The operation of devices including video pulse current transformers, direct current transformers, and gigahertz bandwidth wall current style transformers is described. Design examples are given for each of these types of devices. Sensitivity, frequency response, and physical environment are typical parameters which influence the design of these instruments in any particular application. Practical engineering considerations, potential pitfalls, and performance limitations are discussed

Wavelets a tutorial in theory and applications

CERN Document Server

1992-01-01

Wavelets: A Tutorial in Theory and Applications is the second volume in the new series WAVELET ANALYSIS AND ITS APPLICATIONS. As a companion to the first volume in this series, this volume covers several of the most important areas in wavelets, ranging from the development of the basic theory such as construction and analysis of wavelet bases to an introduction of some of the key applications, including Mallat's local wavelet maxima technique in second generation image coding. A fairly extensive bibliography is also included in this volume.Key Features* Covers several of the

Nanocrystalline TiAl powders synthesized by high-energy ball milling: effects of milling parameters on yield and contamination

International Nuclear Information System (INIS)

Bhattacharya, Prajina; Bellon, Pascal; Averback, Robert S.; Hales, Stephen J.

2004-01-01

High-energy ball milling was employed to produce nanocrystalline Ti-Al powders. As sticking of the powders can be sufficiently severe to result in a near zero yield, emphasis was placed on varying milling conditions so as to increase the yield, while avoiding contamination of the powders. The effects of milling parameters such as milling tools, initial state of the powders and addition of process control agents (PCA's) were investigated. Cyclohexane, stearic acid and titanium hydride were used as PCA's. Milling was conducted either in a Cr-steel vial with C-steel balls, or in a tungsten carbide (WC) vial with WC balls, using either elemental or pre-alloyed powders. Powder samples were characterized using X-ray diffraction, scanning and transmission electron microscopy. In the absence of PCA's mechanical alloying in a WC vial and attrition milling in a Cr-steel vial were shown to lead to satisfactory yields, about 65-80%, without inducing any significant contamination of the powders. The results suggest that sticking of the powders on to the milling tools is correlated with the phase evolution occurring in these powders during milling

LOG: Analyzing navigation trough a tutorial of Radiation Protection

International Nuclear Information System (INIS)

Vega, J. M.; Pena, J. J.; Rossell, M. A.; Calvo, J. L.

2003-01-01

Every day, the number of didactic materials presented through Internet, is greater. However, we have not effective tools to obtain the potential academic yield of such a media. The complexity of the Internet protocols, in spite of the easy handling, makes it almost impossible. In this work, a didactic tool to analyse graphically the navigation through a tutorial on radiation protection is presented. For its visualisation, some subjects related with the biogical effects of radiation and with radiological quantities and units have been selected. The graphical representation shows the tour travelled by the user, in our case students of Medicine, and the time employed in eyeing each one of the nodes. The answers to problems about the contents of each node and its graphical representation in the navigation map allow us to follow the learning progress of the students as well as their standard of navigation. The graphical representation analysis of multiple users permits to detect some of the mistakes in the design of the tutorial and to suggest to the author a method for amending these mistakes. The system is developed on LINEX, but it is easily adaptable to other operating systems. (Author) 7 refs

Integrating Supplementary Application-Based Tutorials in the Multivariable Calculus Course

Science.gov (United States)

Verner, I. M.; Aroshas, S.; Berman, A.

2008-01-01

This article presents a study in which applications were integrated in the Multivariable Calculus course at the Technion in the framework of supplementary tutorials. The purpose of the study was to test the opportunity of extending the conventional curriculum by optional applied problem-solving activities and get initial evidence on the possible…

Learning Marketing Accounting Skills in the Introductory Marketing Course: The Development, Use, and Acceptance of a Self-Study Tutorial

Science.gov (United States)

Chen, Yi Ju; Greenberg, Barnett; Dickson, Peter; Goodrich, Jonathan

2012-01-01

A self-study tutorial designed to teach, through a learning-by-doing application, how important marketing accounting is to the whole firm, and why every business graduate should have a solid understanding of marketing accounting is tested using an exam and satisfaction survey. Performance on the exam and satisfaction with the tutorial depended…

The progress in the researches for uranium mill tailings cleaning treatment and no-waste uranium ore milling processes

International Nuclear Information System (INIS)

Wang Jintang

1990-01-01

The production of uranium mill tailings and their risk assessment are described. The moethods of uranium mill tailings disposal and management are criticized and the necessity of the researches for uranium mill tailings cleaning treatment and no-wasle uranium ore milling process are demonstrated. The progress for these researches in China and other countries with uranium production is reviewed, and the corresponding conclusions are reported

Prepolishing on a CNC platform with bound abrasive contour tools

Science.gov (United States)

Schoeffler, Adrienne E.; Gregg, Leslie L.; Schoen, John M.; Fess, Edward M.; Hakiel, Michael; Jacobs, Stephen D.

2003-05-01

Deterministic microgrinding (DMG) of optical glasses and ceramics is the commercial manufacturing process of choice to shape glass surfaces prior to final finishing. This process employs rigid bound matrix diamond tooling resulting in surface roughness values of 3-5μm peak to valley and 100-400nm rms, as well as mid-spatial frequency tool marks that require subsequent removal in secondary finishing steps. The ability to pre-polish optical surfaces within the grinding platform would reduce final finishing process times. Bound abrasive contour wheels containing cerium oxide, alumina or zirconia abrasives were constructed with an epoxy matrix. The effects of abrasive type, composition, and erosion promoters were examined for tool hardness (Shore D), and tested with commercial optical glasses in an Optipro CNC grinding platform. Metrology protocols were developed to examine tool wear and subsequent surface roughness. Work is directed to demonstrating effective material removal, improved surface roughness and cutter mark removal.

Assessing the impact of a tutorial intervention when teaching the ray model of light in introductory physics

International Nuclear Information System (INIS)

Kesonen, M H P; Asikainen, M A; Hirvonen, P E

2013-01-01

This paper presents a 90 min tutorial intervention which permits the use of the Tutorials in Introductory Physics curriculum in a conventional physics course. In addition, the paper describes the impact of the intervention on students' understanding of the ray model of light in the context of geometrical images. In 2011 and 2012 a total of 79 introductory students participated in the intervention, where they worked with the Light and Shadow tutorial after having received lecture-based instruction in a conventional physics course. The impact of the intervention on the students' learning was assessed by means of paper-and-pencil test questions at the beginning and end of the intervention. The results showed that the proportion of correct or nearly correct answers increased by 17 percentage points during the intervention. Thus, it can be claimed that the intervention was a useful supplement to a conventional physics course by helping students to improve their understanding of the ray model of light. In addition, the intervention may serve as an intermediate step towards adopting the tutorials, since it permits the curriculum of a conventional physics course to be tested without large changes being made to the course. This type of information is needed in support of institutional changes towards more research-based instructional practices. (paper)

75 FR 49524 - Woodland Mills Corporation, Mill Spring, NC; Notice of Affirmative Determination Regarding...

Science.gov (United States)

2010-08-13

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-73,695] Woodland Mills Corporation, Mill Spring, NC; Notice of Affirmative Determination Regarding Application for Reconsideration By application dated July 22, 2010, petitioners requested administrative [[Page 49525

Tutorial Pengenalan Adobe Photoshop Menggunakan Adobe Flash CS3

OpenAIRE

Mayoka, Rio

2011-01-01

Kajian ini bertujuan untuk membangun sebuah aplikasi yang dapat menjadi alat bantu dalam pembelajaran Adobe Photoshop, dimana terdapat beberapa materi pengenalan dasar Adobe Photoshop. Aplikasi ini suatu gagasan dengan membuat tutorial beranimasi yang interatif. Aplikasi ini dibuat dengan menggunakan Adobe Flash CS3 dan dapat dijalankan dengan Flash player. Aplikasi ini dapat membantu para penggunanya dalam memahami pengenalan Adobe Photoshop, terutama pengenalan tool pada Adob...

Taguchi design optimization of machining parameters on the CNC end milling process of halloysite nanotube with aluminium reinforced epoxy matrix (HNT/Al/Ep hybrid composite

Directory of Open Access Journals (Sweden)

J.S. Pang

2014-08-01

Full Text Available This paper introduces the application of Taguchi optimization methodology in optimizing the cutting parameters of end-milling process for machining the halloysite nanotubes (HNTs with aluminium reinforced epoxy hybrid composite material under dry condition. The machining parameters which are chosen to be evaluated in this study are the depth of cut (d, cutting speed (S and feed rate (f. While, the response factors to be measured are the surface roughness of the machined composite surface and the cutting force. An orthogonal array of the Taguchi method was set-up and used to analyse the effect of the milling parameters on the surface roughness and cutting force. The result from this study shows that the application of the Taguchi method can determine the best combination of machining parameters that can provide the optimal machining response conditions which are the lowest surface roughness and lowest cutting force value. For the best surface finish, A1–B3–C3 (d = 0.4 mm, S = 1500 rpm, f = 60 mmpm is found to be the optimized combination of levels for all the three control factors from the analysis. Meanwhile, the optimized combination of levels for all the three control factors from the analysis which provides the lowest cutting force was found to be A2–B2–C2 (d = 0.6 mm, S = 1000 rpm, f = 40 mmpm.

Design of Accelerated Reliability Test for CNC Motorized Spindle Based on Vibration Signal

Directory of Open Access Journals (Sweden)

Chen Chao

2016-01-01

Full Text Available Motorized spindle is the key functional component of CNC machining centers which is a mechatronics system with long life and high reliability. The reliability test cycle of motorized spindle is too long and infeasible. This paper proposes a new accelerated test for reliability evaluation of motorized spindle. By field reliability test, authors collect and calculate the load data including rotational speed, cutting force and torque. Load spectrum distribution law is analyzed. And authors design a test platform to apply the load spectrum. A new method to define the fuzzy acceleration factor based on the vibration signal is proposed. Then the whole test plan of accelerated reliability test is done.

Model & scale as conceptual devices in architectural representation

NARCIS (Netherlands)

Stellingwerff, M.C.; Koorstra, P.A.

2013-01-01

This year we celebrate the tenth anniversary of our Computer Aided Manufacturing laboratory (CAMlab, http://www.camlab-bk.nl). From the start we provide laser cutting, CNC-milling and 3D-print facilities for the students and the researchers at the Faculty of Architecture in Delft. Over the past ten

Maintaining Quality While Expanding Our Reach: Using Online Information Literacy Tutorials in the Sciences and Health Sciences

OpenAIRE

Talitha Rosa Matlin; Tricia Lantzy

2017-01-01

Abstract Objective – This article aims to assess student achievement of higher-order information literacy learning outcomes from online tutorials as compared to in-person instruction in science and health science courses. Methods – Information literacy instruction via online tutorials or an in-person one-shot session was implemented in multiple sections of a biology (n=100) and a kinesiology course (n=54). After instruction, students in both instructional environments completed an ide...

Facilitating Multilingual Tutorials at the University of the Free State

Directory of Open Access Journals (Sweden)

du Buisson Theuns

2017-12-01

Full Text Available Conducting undergraduate studies in the English language, while only a small minority of students speak English at home, poses many problems to learning in the South African context. This article explores how restrictive language policies may influence proper learning and impact negatively on the self-understanding of students. It also explores how multilingualism could help to reduce the continued reliance on English, without doing away with English in its entirety. This is especially relevant in light of English and other colonial languages still being perceived as “languages of power” (Stroud & Kerfoot, 2013, p. 403. Therefore, attention is given to the link between language and power, especially in light of languages often being used to implement, display and preserve power. Language use in the classroom, especially with regard to codeswitching (also called translanguaging, is discussed. Finally, it explores the success that was achieved during multilingual tutorial sessions. In the tutorials, students were encouraged to explore the course work in their native languages, thereby internalising it and getting a better understanding thereof.

Black holes with Yang-Mills hair

International Nuclear Information System (INIS)

Kleihaus, B.; Kunz, J.; Sood, A.; Wirschins, M.

1998-01-01

In Einstein-Maxwell theory black holes are uniquely determined by their mass, their charge and their angular momentum. This is no longer true in Einstein-Yang-Mills theory. We discuss sequences of neutral and charged SU(N) Einstein-Yang-Mills black holes, which are static spherically symmetric and asymptotically flat, and which carry Yang-Mills hair. Furthermore, in Einstein-Maxwell theory static black holes are spherically symmetric. We demonstrate that, in contrast, SU(2) Einstein-Yang-Mills theory possesses a sequence of black holes, which are static and only axially symmetric

Hadoop Tutorials - Hadoop Foundations

CERN Multimedia

CERN. Geneva; Lanza Garcia, Daniel

2016-01-01

The Hadoop ecosystem is the leading opensource platform for distributed storage and processing of "big data". The Hadoop platform is available at CERN as a central service provided by the IT department. This tutorial organized by the IT Hadoop service, aims to introduce the main concepts about Hadoop technology in a practical way and is targeted to those who would like to start using the service for distributed parallel data processing. The main topics that will be covered are: Hadoop architecture and available components How to perform distributed parallel processing in order to explore and create reports with SQL (with Apache Impala) on example data. Using a HUE - Hadoop web UI for presenting the results in user friendly way. How to format and/or structure data in order to make data processing more efficient - by using various data formats/containers and partitioning techniques (Avro, Parquet, HBase). ...