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Customers perceptions of the use of internet in the marketing communication: A case study of a retail laptop companyUllah, Md. Mahbub January 2011 (has links)
The rapid growth of the Internet has provided tremendous opportunities for laptop companies to offer quality of customer service. The prime drivers and motivations for offering such customer service through the web are to reduce service costs and to provide efficient and effective service to customers. In the business of laptop RANGS electronics Limited (REL) is a new company which aims to achieve business excellence through quality product by satisfying customer expectations. But what are the marketing media essential for building a successful customer service operation in REL business? This paper addresses this specific issue by isolating the essential elements from the available literature, and assessing them individually from interviews to obtain better insights and understanding. The respondents were Swedish, Chinese and Bangladeshi students studying in Orebro and Karlstad University. In order to find a suitable media for the REL marketing of laptop, the data gathered was analyzed and compared groups of concepts related to the purpose and the research question. The result suggests that online service delivery has greater charm to customers for its low or limited levels of complexity. The three important concepts to establish the service into customers mind are developing speedy service, increasing customer affiliation through networking and engaging customer into product marketing. This could help REL to design and develop robust foundations on which to build successful customer service operations. The foundations between the service and e-business were sometimes confusing. This paper clarifies some of these opacities.
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Modeling and Verification of Cutting Tool Temperatures in Rotary Tool Turning of Hardened SteelDessoly, Vincent 08 April 2004 (has links)
The chip formation process in machining is accompanied by heat generation. The heat generated influences both the workpiece physical properties as well as the cutting tool. High temperatures accelerate tool wear and thermal softening which are not desirable because they alter the accuracy of the machined surface and tool life.
Many studies have been done to lower the heat generated in cutting. A first approach is to use a cutting fluid but its effectiveness is limited by its ability to penetrate between the tool and the chip. A second approach is to remove the heat generated through a cooling cycle as in interrupted cutting. The idea is either to translate a wide tool to the side as it moves forward relative to the workpiece, which allows the dissipation throughout the body of the tool or to use a cutting edge in the form of a disk that rotates about its principal axis. The latter, known as a rotary tool, provides a rest period for the cutting edge, thus enabling the edge to be cooled and a continuously fresh portion of the edge to be engaged with the workpiece. The rotary tool can be either driven by an external power source or self-propelled.
This thesis focuses on the self-propelled rotary tool (SPRT) process for machining of difficult-to-machine material such as bearing steels, where tool life is of particular concern. Since the cutting temperatures are known to influence tool life significantly, the first task in this investigation involved developing a model to analyze heat transfer and temperature distribution in the cutting tool during SPRT turning of the hardened 52100 steel (58 HRC). Both rotary and equivalent fixed tool processes are compared in terms of cutting tool temperatures generated. The model is based on the moving heat source theory of conduction and employs the Finite Element Method (FEM) for its solution. The model is experimentally verified through measurement of the cutting temperature distribution using an Infra-Red imaging camera under different cutting conditions. Predicted and measured temperatures show good overall agreement when they are measured along the cutting edge and measured temperatures are up to 50??ower in rotary tool cutting than in fixed tool cutting under the same conditions.
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Studies on the Friction Stir Welding of Aluminum Alloy Sheets by Using High Speed Steel Tool Inserted Aluminum AlloySu, Fang-Hua 19 August 2011 (has links)
In this study, a novel inserted type of friction welding tool was
proposed, where the circular rod was embedded in its central axis using the
material same as the workpiece, so that it could effectively promote the
friction heat quickly and enhance the welding quality. The welding tool
was made of the high-speed steel, the workpiece with its embedded
material 6061-T6 aluminum alloy. A vertical milling machine equipped
with dynamometer, which could measure the power during the friction stir
welding, was employed as the experimental apparatus. During the welding
process, the K-type thermocouple was used simultaneously in measuring
the welding temperature at the interface of joint. The operating conditions
of welding were as followings: the welding speed of 800 rpm, the tool
inclination of 1¢X and the clamping force 2kN, the tool with 12mm in
diameter and 0.21mm in depth under the downward force about 2 kN. The
experiment was conducted into two stages.
The first stage was a spot welding to investigate the effect of the ratio
of the diameter of embedded material (d) to the diameter of welding tool (D)
on the temperature of the interface of joint, the thickness of plastic flow,
and the failure load of weld. Experimental results revealed that the interface
temperature, the plastic flow thickness, and the failure load of weld are
directly proportional to d/D. In comparison with the welding tool without
insert (d/D = 0), the maximum interface temperature increased about 1.12
times at d/D = 0.83, the plastic flow thickness increased about 1.52 times,
and the failure load of weld increased about 1.45 times. In the second stage,
the feeding process was included to investigate the influence of the
diameter and the thickness of embedded material on the interface
temperature, the plastic flow thickness, and the failure load of weld.
Experimental results revealed that the plastic flow thickness was less than 2
mm when the thickness of embedded material was less than 3 mm.
However, when the thickness of embedded material was larger than 5 mm,
the plastic flow thickness could achieve to 3 mm. Hence, the thickness of
embedded material should be larger than 5mm. Moreover, the effect of the
diameter of embedded material on the interface temperature and the plastic
flow thickness using the feeding process was almost the same as the spot
welding. However, in comparison with the welding tool without insert, the
failure load of weld increased about two times.
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Feasibility studies on the friction stir welding of the multi-laminated silicon steel sheetsLin, Jia-Shiang 22 August 2011 (has links)
A friction stir welding equipment with high rotation speed and constant load is successfully developed in this study to weld the multi-laminated silicon steel sheets widely used on regular transformers. This equipment consists of a spinning unit, a loading unit, and a feeding unit. A WC round rod with 3 mm diameter is used as welding tool. Under different operating conditions, such as the normal load(140~480 N), the spindle speed (12000~24000rpm), the feeding rate (0~1.58 mm/s), the welding characteristics and the welding mechanism of multi-laminated silicon steel sheets, and the welding feasibility of the transformer are investigated.
Firstly, the contour map of welding depth in terms of spindle speed,normal load, and depth of point welding is established for dwell welding time 15 seconds.
Secondly, based on this contour map, two experimental conditions of the long-pass welding tests are selected to investigate the effect of normal load (Fd), the spindle speed (Ns), and the feeding rate (f) on the failure load of weld under the shear. According to the experimental results, the empirical formula is obtained as Ff =40.6(Fd¡DNs)1.123(f)-0.791. In this formula,(Fd¡DNs)1.123(f)-0.791 is proportional to the frictional work per unit moving distance. With the larger frictional work, this represents the heat generation of the workpiece material is higher with more uniform friction stir, so that the bonding strength of the material increases and the failure load of weld is larger.
According to the micrograph observations, the thermo-mechanically affected zone is significantly influenced by high heat action generated from the friction between the tool and the weld surface region, so that the plastic flow of the workpiece material occurs to cause the multi-laminated silicon steel sheets bonding together.
Finally, the transformer is successfully welded under the experimental conditions of the long-pass welding tests with the smaller welding depth and the better failure load.
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A study on the key success factors of international market management for machine tool industry in TaiwanLin, Shih-Chao 18 January 2012 (has links)
Under greatly improvement in manufacturing quality and R¡®D capacity, Taiwanese Machine Tool Industry gradually emerging on the international and saturated domestic market in recent years. Also, domestic market is gradually saturated; machine tool manufacturer is forced to move out of Taiwan. It also caused Taiwan tool industry to internationalize and step into the phase of international market management. Most enterprise scale of Taiwan machine tool industry belong to small and medium-sized ones. Under limited resource, it is a critical issue to allocate the resource efficiently and to control the key success factors of international marketing management.
This research use publicly listed machine tool industry companies in Taiwan to be the study object. First, besides collecting related literatures in domestic and overseas, this research also used questionnaire and interviewees to study the key success factors of Taiwanese Machine Tool Industry international market management, by conclude the following four factors, which were entire environment, industrial structure, business competitive advantages and international market strategy. Secondly, the AHP (Analysis Hierarchy Process) will be used as analysis method to evaluate the importance of key success factors in Taiwanese Machine Tool Industry international market management. Finally, the results showed that the most important five factors of the key success factors in Taiwanese Machine Tool Industry international market management were: 1) Enterprise's brand/Business goodwill; 2) Tax reduction policy; 3) Global marketing networks management; 4) Key components of self-control and 5) The impact of the international environment. The weight ratio of factors could provide the Taiwanese Machine Tool Industry as the index for operating in foreign markets
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Modelling of Tool Life and Micro-Mist flow for Effective Micromachining of 316L Stainless Steel.Kajaria, Saurabh 2009 December 1900 (has links)
Recent technoligical advancement demands new robust micro-components made out of engineering materials. The prevalent methods of manufacturing at micro-nano level are established mostly for silicon structures. Therefore, there is interest to develop technologies for micro-fabrication of non silicon materials.
This research studies microend-milling of 316L stainless steel. Machine tool requirement, tool modeling, cutting fluid evaluation, and effect of cutting parameters are investigated. A machine tool with high rigidity, high spindle speed, and minimal runout is selected for successful micro-milling. Cumulative tool wear and tool life of these micro-tools are studied under various cutting conditions.
Ideal abrasive wear is observed when applying mist cooling whereas inter-granular shearing is the major failure mode while flood cooling or dry cutting during micro-machining. Various experiments and computational studies suggest an optimal position of the mist nozzle with respect to a tool that provides maximum lubrication at the cutting edge. Mist droplets effectively penetrate the boundary layer of a rotating tool and wet the cutting edge and significantly improve the tool life.
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Two-stage Ignition as an Indicator of Low Temperature Combustion in a Late Injection Pre-mixed Compression Ignition Control StrategyBittle, Joshua 2010 December 1900 (has links)
Internal combustion engines have dealt with increasingly restricted emissions requirements. After-treatment devices are successful in bringing emissions into compliance, but in-cylinder combustion control can reduce their burden by reducing engine out emissions. For example, oxides of nitrogen (NOx) are diesel combustion exhaust species that are notoriously difficult to remove by after-treatment. In-cylinder conditions can be controlled for low levels of NOx, but this produces high levels of soot potentially leading to increased particulate matter (PM). The simultaneous reduction of NOx and PM can be realized through a combustion process known as low temperature combustion (LTC).
In this study, the typical definition of LTC as the defeat of the inverse relationship between soot and NOx is not applicable as a return to the soot-NOx tradeoff is observed with increasing exhaust gas recirculation (EGR). It is postulated that this effect is the result of an increase in the hot ignition equivalence ratio, moving the combustion event into a slightly higher soot formation region. This is important because a simple emissions based definition of LTC is no longer helpful. In this study, the manifestation of LTC in the calculated heat release profile is investigated.
The conditions classified as LTC undergo a two-stage ignition process. Two-stage ignition is characterized by an initial cool-flame reaction followed by typical hot ignition. In traditional combustion conditions, the ignition is fast enough that a cool-flame is not observed. By controlling initial conditions (pressure, temperature, and composition), the creation and duration of the cool-flame event is predictable. Further, the effect that injection timing and the exhaust gas recirculation level have on the controlling factors of the cool-flame reaction is well correlated to the duration of the cool-flame event. These two results allow the postulation that the presence of a sufficiently long cool-flame reaction indicates a combustion event that can be classified as low temperature combustion. A potential method for identifying low temperature combustion events using only the rate of heat release profile is theorized.
This study employed high levels of EGR and late injection timing to realize the LTC mode of ordinary petroleum diesel fuel. Under these conditions, and based on a 90 percent reduction in nitric oxide and no increase in smoke output relative to the chosen baseline condition, a two part criteria is developed that identifies the LTC classified conditions. The criteria are as follow: the combustion event of conventional petroleum diesel fuel must show a two-stage ignition process; the first stage (cool-flame reaction) must consume at least 2 percent of the normalized fuel energy before the hot ignition commences.
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Development and Testing of Achievement from Multiple Modes of Mathematical Representation: Audio, Audio-Visual, and KinestheticOzel, Serkan 2009 August 1900 (has links)
This dissertation is comprised of three articles that build on and support each other. The first article is an extensive literature review, and the other two are empirical studies. In this literature review, the author discussed major theories about human learning processes to guide instructional designers about effective integration of multiple modes in interactive learning environments and explored the knowledge base on representations and manipulatives in mathematics education.
The first empirical study?s purpose was to investigate effects of affordances provided with virtual learning environments at different treatment durations. Students from multiple sixth-grade classes were randomly assigned to one of three treatment groups differed by allocated session time (10-, 20-, and 30-minute). The online manipulative tool (OMT), which was designed to scaffold learning in operations with rational numbers, allowed students to use the following three components in any order: (a) audio, (b) audio-visual, and (c) manipulatives. Analyses showed that students who used manipulatives most achieved highest; whereas, students who used audio-visual most achieved the second highest. Additionally, the 30-minute group used each component of OMT the least. A meaningful increase in standard algorithm use over manipulatives suggested a transition from concrete to abstract thinking.
The second empirical study's purpose was to compare OMT's different representational aspects and to estimate OMT's effects on achievement and technology acceptance when compared to those of traditional classroom activities. Elementary- and middle-grade students were randomly assigned to the control group or one of three treatment groups: (a) audio-visual, (b) virtual-kinesthetic, and (c) dual-mode (virtual-kinesthetic and audio-visual combined).
When the control group was compared with experimental groups, pre- and post-test results suggested that OMT was more effective than traditional classroom activities in improving students' understanding of operations with rational numbers. When the students' achievement on pre- and post-tests among experimental groups was compared, no substantial difference was found. However, students in the dual-mode group scored the highest on the technology acceptance survey. Students' technology acceptances also differed among different SES levels but not genders. The results suggested that virtual manipulatives provided additional affordances for conceptual understanding. However, students' acceptances of technology should be considered when implementing new technologies.
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Constructing Event Ontology and Episodic Knowledge from DocumentYang, Yi-cheng 20 July 2007 (has links)
Knowledge is an increasingly important asset for organizational competition, and knowledge management becomes the most important issue for an organization. Building knowledge ontology is a good solution to increase knowledge reusability. Ontology explicitly defines concepts and their relationships, which can facilitate user understanding and further analysis.
Based on previous research (Wu, 2006; Chuang, 2006), this research proposes a refined method for the construction of event ontology. The method includes text pre-processing, event ontology construction, and event ontology presentation. The text pre-processing module includes POS tagger, word filter, and term analysis. Based on the concept of sub-event, we can build a 3-level architecture of event ontology that includes sub-events, events, and topics in the event ontology construction module. Event ontology construction module developed in the project provides a friendly editing environment for the user to edit the concepts and attributes of an event that may cover ¡§who,¡¨ ¡§what,¡¨ ¡§where,¡¨ and ¡§what object.¡¨ In the event ontology presentation module, event episode may be illustrated by event frames, flow charts, and Gantt charts.
To verify the feasibility of the proposed method, a prototype system has been built. The Alexander Poison Event was used as an example to demonstrate the value of the prototype system.
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Implementation And Simulation Of Mc68hc11 Microcontroller Unit Using Systemc For Co-design StudiesTuncali, Cumhur Erkan 01 December 2007 (has links) (PDF)
In this thesis, co-design and co-verification of a microcontroller hardware and software using SystemC is studied. For this purpose, an MC68HC11 microcontroller unit, a test bench that contains input and output modules for the verification of microcontroller unit are implemented using SystemC programming language and a visual simulation program is developed using C# programming language in Microsoft .NET platform.
SystemC is a C++ class library that is used for co-designing hardware and software of a system. One of the advantages of using SystemC in system design is the ability to design each module of the system in different abstraction levels. In this thesis, test bench modules are designed in a high abstraction level and microcontroller hardware modules are designed in a lower abstraction level.
At the end, a simulation platform that is used for co-simulation and co-verification of hardware and software modules of overall system is developed by combining microcontroller implementation, test bench modules, test software and visual simulation program. Simulations at different levels are performed on the system in the developed simulation platform. Simulation results helped observing errors in designed modules easily and making corrections until all results verified designed hardware modules. This stuation showed that co-designing and co-verifying hardware and software of a system helps finding errors and making corrections in early stages of system design cycle and so reducing design time of the system.
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