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ENTERPRISE RESOURCE PLANNING SYSTEM SUCCESS IN CORPORATE SECTOR OF PAKISTAN: A MIXED METHODS APPROACH
No full textIn the last few decades Information Technology (IT) has grown manifolds in Pakistan.\ud
The dynamic organizations are continuously replacing their legacy systems with the \ud
contemporary information systems (IS). Particularly, Enterprise Resource Planning (ERP) \ud
systems are now becoming an integral part of the organizations to automate business processes. \ud
This thesis empirically investigated: (1) the success of ERP system at individual, process and \ud
organizational levels and (2) explored different contextual factors relating to organization, \ud
technology, individual and environment that affect the level of ERP system success in corporate \ud
sector of Pakistan. For examining ERP system success, the study applied DeLone and McLean \ud
(1992, 2003) (D&M) 'Theory of IS Success'. The five dimensions mentioned in the theory and \ud
an additional dimension was incorporated in the proposed ERP system success measurement \ud
model i.e., ERP system quality, ERP information quality, ERP service quality, individual \ud
performance, organizational performance and process performance (added to the model). The \ud
present study applied two phased 'explanatory sequential' mixed methods research design. \ud
In the first phase of research 514 Pakistani organizations were surveyed through\ud
structured questionnaires to investigate ERP system success. SmartPLS 3 Software was used \ud
and Partial Least Square - Structural Equation Modeling (PLS-SEM) technique was applied for \ud
testing the study hypotheses and assessing convergent validity, discriminant validity and internal \ud
reliability of the constructs. The results from the first phase indicated that ERP system quality, \ud
information quality and service quality positively influence individual performance. Similarly, \ud
individual performance has also positive and significant relation with process performance and \ud
organization performance. The results also revealed that process performance has positive and \ud
significant impact on organizational performance in Pakistani organizations. \ud
Based on the findings from the first phase, qualitative research strategy was applied in the \ud
second phase of research to explore different contextual factors that affect the level of ERP \ud
system success in corporate sector of Pakistan. The qualitative data was collected through in\ud
depth video recorded interviews of 48 ERP key users in four different organizations. NVivo 10 \ud
software was used for transcribing, coding and identifying different themes of the study. Word \ud
Tree, Word Tag Clouds and Tree Maps techniques were applied to identify frequency of data \ud
coding, talk pattern and significance of each contextual factor. Finally, the qualitative phase of \ud
research explored that rewards and incentives, training, leadership, management control, \ud
technological resources, up-gradation of technology, skills, knowledge, provision of electricity \ud
and stakeholders' pressure are more critical factors that influence the level of ERP system \ud
success in Pakistani organizations. Thus, these findings suggest that organizations can enhance \ud
the level of ERP system success by controlling these contextual factors. \ud
Lastly, the both quantitative and qualitative results were discussed and different \ud
theoretical and practical implications were provided. The findings of the study will serve as \ud
changing driver of attention of the practitioners from the issues of pre-implementation or \ud
implementation stages to the issues of post-implementation stage of ERP system. Based on \ud
different results and discussions, practitioners will pay more attention to sustain the success of \ud
ERP system in their organizations
Robust Control System Design for a Class of Uncertain\ud Nonlinear Systems
No full textThe work presented in this thesis is an endeavor to combine two nonlinear control frameworks in order to utilize the beneficial attributes of adaptive backstepping and sliding mode control or integral sliding mode control techniques. The adaptive backstepping method is capable of eliminating external disturbances and dynamically estimating the unknown parameters. This technique solves the problem of relative degree which is the main drawback of conventional sliding mode control method. It is also globally effective for the stability of the nonlinear control systems. The sliding mode control is another widely used method due to its robustness against matching uncertainties. The robustness of nonlinear system can be enhanced by adding an integral term with the sliding manifold of sliding mode control method. This attribute is achieved by eliminating the reaching phase of sliding mode control which makes it immune against fast parametric variations that occurs during reaching phase.\ud
On the basis of this synergy, new strategies have been proposed which are named as Adaptive Backstepping Higher Order Integral Sliding Mode Control (ABHOISMC), and Adaptive Backstepping Integral Sliding Mode Control (ABISMC), and based on our simulation studies, they are found to be more robust against both matching and mismatching uncertainties. During the implementation of newly proposed techniques, it is not necessary to transform the system into triangular form which is generally needed in the conventional backstepping procedure.\ud
The first proposed scheme, the ABISMC, is applied to control the parameters of continuous stirred tank regulator plant with its model expressed mathematically in a non-triangular form. The simulation results establish the efficacy of the proposed scheme. As a second example, the ABISMC is also applied for the tracking of the desired output in a field-controlled direct-current motor. The simulation results are found to be very convincing. Finally, the second proposal, the ABHOISMC, is applied on a theoretical plant expressed in a semi-strict feedback form; the resulting simulation findings substantiate our claims.\ud
"Nothing is done. Everything in the world remains to be done or done over. The greatest picture is not yet painted, the greatest play isnt written, the greatest poem is unsung. There isnt in all the world a perfect railroad, nor a good government, nor a sound law. Physics, mathematics, and especially the most advanced and exact of the sciences are being fundamentally revised ··· Psychology, economics, and sociology are awaiting a Darwin, whose work in turn is awaiting an Einstein.
Automatic Colon Cancer Detection and Classi?cation
No full textIn the past two decades, automatic colon cancer detection has become an active research\ud
area. Traditionally, colon cancer is diagnosed using microscopic analysis of pathological\ud
tissue imagery. However, the process is subjective and leads to considerable inter/intra\ud
observer variation in diagnosis. Therefore, reliable computer-aided colon cancer diagnostic\ud
systems are in high demand. In this thesis, a computer-aided colon cancer diagnostic (CAD)\ud
system has been proposed that comprises three main phases.\ud
In the ?rst phase, an unsupervised colon biopsy image segmentation technique, which is\ud
based on a few novel extensions in traditional object oriented texture analysis based seg\ud
mentation technique, has been developed. The second phase deals with classi?cation of\ud
colon image and gene based datasets into normal and malignant classes. For the colon\ud
biopsy image based datasets, two classi?cation techniques based on hybridization of var\ud
ious features have been proposed. In these techniques, some traditional features such as\ud
morphological and texture, variants of traditional features, and some novel features which\ud
have especially been designed to capture the variation between normal and malignant colon\ud
tissues have been used. Similarly, for the gene expression based dataset, a novel technique\ud
that utilizes various feature selection strategies for solving the challenging problem of larger\ud
dimensionality of gene based datasets, and a weighted majority voting based ensemble of\ud
various SVM classi?ers for performance improvement has been proposed.\ud
In the third phase of this work, the structural variation in the shape of lumen among var\ud
ious colon cancer grades has been quanti?ed in terms of a few novel structural features.\ud
These features are used for the classi?cation of malignant colon biopsy images into vari\ud
ous cancer grades. Performance of the proposed diagnostic system has been validated on\ud
various datasets, and superior qualitative and quantitative performance has been observed\ud
compared to previously reported methods of colon cancer detection
Studies of Exchange Bias and Coercivity in Magnetic Nanocomposites and Thin Film Nanostructures
No full textIn this work exchange bias and coercivity of zero dimensional (0-D) nanoparticles, two dimensional (2-D) nanodots and three dimensional (3-D) nanoclusters have been studied. An important motivation was to study the effects of exchange anisotropy, configurational anisotropy and surface anisotropy on exchange bias and coercivity. Three types of systems have been fabricated using ferromagnetic cobalt (Co) and antiferromagnetic chromium (III) oxide (Cr2O3). These are Co-Cr 2O3 nanocomposites, two-dimensional triangular nanodots of Co and Cr2O3 bilayers, three dimensional nanoclusters of Co on a Cr2O3 underlayer.</BR> \ud
Co-Cr2O3 nanocomposites have been synthesized using the sol-gel technique. Co concentration has been varied from 30 to 80 weight %. These composites consist of Co particles having diameter 3-4 nm embedded in a Cr2O3 matrix with particle mean diameter of 24 nm which increases to 34 nm upon extended annealing. The independent AFM grain volume model has been used to model and explain the results obtained on nanocomposites samples. Using this model and the York protocol of thermal activation measurements, the contributions to exchange bias arising from the bulk of the antiferromagnet have been successfully separated from those due to the ferromagneticantiferromagnetic interfaces. This interfacial contribution to exchange bias has been measured and found to attain a maximum at about 40 wt.% of Co in the Cr2O3 matrix.\ud
Two dimensional (2-D) triangular nanodots were prepared using polystyrene nanosphere lithography in conjunction with magnetron sputtering. Two different dot sizes with side 240 nm and 120 nm were prepared using nanospheres with diameter 500 nm and 1 ?m respectively. The thickness of Co in the nanodots has been varied from 5 nm to 12 nm, while the thickness of the Cr2O3 layer has been kept constant at 23 nm in all samples. Continuous films of the same thicknesses have also been investigated and compared with pure ferromagnetic and exchange biased nanodots in order to study the\ud
effect of discretization on the magnetic properties. The coercivity of ferromagnetic nanodots was found to be larger than that of both ferromagnetic as well as exchange biased continuous thin films. The exchange biased nanodots showed a very large increase in the exchange bias and coercivity over that of the continuous exchange biased film. These effects have been explained in terms of interfacial exchange anisotropy and configurational anisotropy of not only the ferromagnet but the antiferromagnet as well. \ud
Three dimensional (3-D) nanoclusters have been fabricated using buffer layer assisted growth (BLAG) on silicon substrates as well as on continuous Cr2O3 continuous films. The sizes of the nanoclusters were varied from 38 nm to 68 nm. The effect of dimensionality on the magnetic properties of the nanoclusters has been studied and compared to 2-D nanodots. Clusters grown on the antiferromagnetic Cr2O3 layer show an increase in the coercivity over that of clusters grown only on the Si substrate; however, no exchange bias could be observed. The results have been explained in terms of the competition between the interfacial exchange energy and the anisotropy energy of the antiferromagnet
Potential of SiRNA and Artificial MiRNAs Against Cotton Leaf Curl Burewala Virus V2 Gene Yielding Resistance to Begomoviruses
No full textDiseases of crop plants caused by begomoviruses (whitefly-transmitted viruses of the family Geminiviridae) are a major constraint to productivity across the warmer parts of the world. Cotton leaf curl disease (CLCuD) across Pakistan and northwestern India has caused severe losses to cotton cultivation since the early 1990s. In Pakistan the disease at this time is caused by a single begomovirus, Cotton leaf curl Burewala virus (CLCuBuV), and a betasatellite, Cotton leaf curl Multan betasatellite (CLCuMuB). Efforts to prevent losses due to CLCuD rely on the use of insecticides to control the vector whitefly and the use of tolerant cotton varieties; no immune varieties so far having been identified. RNAi technology offers a possible mechanism of rapidly developing resistant crop varieties to counter diseases caused by plant-infecting viruses. Here antisense RNA and artificial micro (ami)RNA have been investigated for their potential to yield resistance to CLCuBuV. A major challenge to use of RNAi is the need to identify the best target sequence. Here three fragments of the virion-sense gene V2 of CLCuBuV have been transformed into Nicotiana benthamiana in antisense orientation and assessed for their ability to yield resistance against CLCuBuV and three heterologous begomoviruses. The results are consistent with the idea that RNAi is a homology-based response with transgenic plants showing levels of resistance that correlate with the levels of sequence identity between the transgene and the inoculated virus. However, only for CLCuBuV was resistance at near immunity levels with the V2 sequence closest to the promoter providing the best resistance. Nevertheless, with all three constructs, transgenic plants inoculated with CLCuBuV showed no symptoms, or recovered from initial mild symptoms, and viral DNA levels were low. Additionally, inoculation of CLCuBuV with the CLCuD-associated betasatellite CLCuMuB to transgenic plants did not significantly affect the outcome although it increased the numbers of plants in which viral DNA could be detected, suggesting that the betasatellite may impair RNAi resistance. This effect is likely due to the betasatellite encoding a strong suppressor that inhibits RNAi at both the transcriptional and posttranscriptional levels. \ud
Earlier studies have shown that the sequences of naturally occurring miRNA genes can be changed to alter the messenger RNAs that they bind to. Here a cotton microRNA gene (miR169a) was altered to replace the sequence of the mature miRNA with 21 nucleotides of sequence from the V2 gene of CLCuBuV and transformed into N. benthamiana. Two constructs were produced. In one construct (P1CN) the sequence of the miRNA backbone, with the exception of the 21 nucleotides, was left unchanged. In the other (P1DM) the sequence of the backbone was changed to, at least in part, restore the secondary structure of the immature miRNA (referred to as a precursormiRNA). Inoculation of plants with a range of begomoviruses showed P1CN to give efficient resistance against the homologous virus (CLCuBuV) but not against heterologous viruses. Overall the levels of resistance exhibited depended upon the levels of sequence identity to the target (21nt) sequence, although other factors also likely play a part. For a small number of P1CN plants inoculated with CLCuBuV symptoms were initially evident but the plants recovered and contained low levels of viral DNA. In contrast, transgenic plants inoculated with heterologous viruses showed a greater number of plants symptomatically infected, that did not recover and showed high levels of viral DNA although lower than in infected non-transgenic plants. Transgenic plants harbouring P1DM showed poor resistance to CLCuBuV and little resistance to the heterologous viruses, indicating that the backbone sequence of the premiRNA is important for the biogenesis of mature miRNA. The results indicate that both antisense-RNA and amiRNA have the potential to deliver resistance against begomoviruses. The significance of the results are discussed
Heuristic Approach for Robust Visual Object Tracking
No full textVisual Object Tracking (VOT) is an important field of computer vision which has a number of applications in different fields, including military as well as commercially available security and surveillance systems. The contribution of the thesis in this field is many folds. \ud
Firstly, a comprehensive survey of different classical and contemporary approaches for VOT is presented. It enables swift understanding of old as well as new trends in this field. \ud
Secondly, a novel method for template (appearance model of the target) updating is presented. It adaptively updates the template according to the rate of change of target's appearance. Comparison with existing template updating techniques shows the robustness of the proposed template updating method against the template drift as well as the stagnation to the old appearance problems. \ud
Thirdly, a new approach for VOT is proposed which combines correlation, Kalman filter and adaptive kernel fast mean shift algorithms, heuristically. Correlation tracker is, generally, computation intensive (if the search space or the template is large) and it suffers from the template drift problem. Moreover, it fails in case of fast maneuvering target, rapid appearance changes, occlusion, and clutter in the scene. These issues are handled by using the proposed template updating method and Kalman filter (KF) with correlation tracker. The threshold for template updating is made adaptive by using current peak correlation value in the proposed tracking framework. KF predicts the target coordinates for the next frame, if the measurement vector is supplied to it by a correlation tracker. Thus, a relatively small search space can be determined where the probability of finding the target in the next frame is high. This way, the tracker becomes fast and rejects the clutter which is outside the search space in the scene. However, if the tracker provides wrong measurement vector due to the clutter or the occlusion inside the search region, the efficacy of the filter is significantly deteriorated. In this case, KF predicted position is far apart from the correlation measured position. Similar situation arises, if a moving target suddenly \ud
changes its direction. In order to handle such scenarios, Fast Mean Shift (FMS) vector is computed inside the difference image of two consecutive search windows to find out the cluster of template size in it, which is considered as a target candidate. FMS kernel is made adaptive according to varying size of target. The proposed tracker considers the KF prediction position as the true target position if it is close to the FMS generated position. Otherwise, the correlation measurement is followed. Comparison with state-of-the-art tracking algorithms on publicly available standard datasets shows that the proposed algorithm outperforms the other algorithms in most of the cases. \ud
Fourthly, a stabilized active camera tracking system is presented. It comprises of a camera mounted on a Pan-Tilt Unit (PTU) which is placed on a moving platform. Jitters are produced in video from the camera due to vibrations in the moving platform which may cause strains in the eyes of the viewer. The outcome of the proposed tracking algorithm is employed to digitally stabilize the video without any significant computational overhead. Experimental results show the efficacy of the proposed algorithm
Fabrication and Characterizations of Piezoelectric Ceramic/Polymer Composites with 1-3 Connectivity
No full textPiezoceramic/polymer composites with 1-3 connectivity are the most extensively \ud
studied and utilized for different applications among existing 10 types of diphasic \ud
composites. This type of composite consists of individual piezoceramic rods or fibers \ud
aligned in the direction parallel to poling and embedded in a polymer matrix. The \ud
piezoceramic fiber or rods play an active role for energy conversion between the \ud
mechanical and electrical energy, while the polymer phase acts as a passive medium \ud
and transfers the mechanical energy between the piezoelectric ceramic and surrounding \ud
with which the composite interacts. These composites are widely used in underwater \ud
hydrophone applications, ultrasound actuators and sensors in medical diagnostic \ud
devices. \ud
In this study, piezoceramics modified compositions; Pb/Co doped barium \ud
titanate (Ba0.95Pb0.05)(Ti0.99Co0.01)O3 (BT-PC) and Sr doped lead zirconate titanate \ud
(Pb0.94Sr0.04)(Zr0.52Ti0.48)O3 (PZT-S) were synthesized through solid state reaction \ud
method. Self-synthesized BT-PC powder has particle size ~0.4µm and after sintering and poling its key properties were; ?r= 1100, d33= 136pC/N, g33= 14×10-3 Vm/N, \ud
kt=31%, and tan?= 0.005. Likewise, the basic properties of the PZT-S were; ?r= 1327, d33= 335pC/N, g33= 29×10-3 Vm/N, kt=45%, and tan?= 0.030. Beside these, a novel Pb\ud
free potassium sodium niobate (KNN) based optimized composition \ud
0.9475(Li0.02(Na0.53K0.48)0.98)(Nb0.80Ta0.20)O5-0.0525AgSbO3-0.5wt.%MnO2, (LKNNT -AS-M) with electrical properties; ?r= 1927, d33= 287pC/N, g33= 17×10-3 Vm/N, \ud
kt=38%, and tan?= 0.038 was also used as an active phase. Monothane-A70, araldite\ud
F, and Epo-Tek 301 were used as a passive polymer matrix in this work. \ud
Three different techniques named as; a novel die-pressing technique, modified \ud
align-and-fill, and improved dice-and-fill technique were used for the fabrication of \ud
1-3 composites. Several series of the composites including; BT-PC/monothane-A70, \ud
PZT-S/monothane-A70, PZT-S/araldite-F, and LKNNT-AS-M/Epo-Tek 301 with \ud
varying piezoceramics rods diameter, spacing between the rods and aspect ratio were \ud
developed. The composites developed through die-pressing and align-and-fill \ud
techniques possess piezoceramics rods diameter ?1.20mm and ?0.78mm respectively \ud
with ceramics contents 11-35 vol. %. However, with dice-and-fill process the LKNNT \ud
AS-M ceramic pillars cross-sectional dimensions were 50×50µm with relatively high \ud
aspect ratio up to 11. \ud
In addition, an underwater transducer with sample changing options was \ud
developed indigenously. Disc shape samples of monolithic piezoceramic and 1-3 \ud
composite were assembled in the self-designed transducer individually. Transducer's \ud
underwater voltage receiving sensitivity (Sh) and transmitting voltage response (Sv) \ud
were investigated in the frequency range 10-200 kHz using a calibrated projector \ud
method with pulse technique \ud
Developed 1-3 composites were passed through comprehensive microstructural, \ud
dielectric, elastic and resonance investigations. Results revealed that all the fabricated \ud
1-3 composites possess clear thickness resonance modes without any mode coupling. \ud
The BT-PC/monothane-A70 composites exhibited thickness coupling factor kt (?44%), figure of merit FOM (up to 7169fm2/N), acoustic impedance Z (8-13Mrayl) and elastic stiffness C33D (36-65GPa). The PZT-S based composites exhibited superior properties \ud
due to high piezoelectric charge coefficient (d33~335 pC/N) and high electromechanical \ud
coupling coefficient (k33~67%) of PZT-S compared to BT-PC piezoceramic. In addition, low stiffness (C33D ~ 21-55 GPa) PZT-S/monothane-A70 composites have \ud
better acoustic impedance (Z ~ 6-14 Mrayl), high charge coefficient (d33~202-271 \ud
pC/N), high hydrostatic charge and voltage coefficients (dh ~ 136-171 pC/N, gh ~ 33114×10-3 Vm/N) and high figure of merit (FOM ~ 4488-19364 fm2/N) compared to the PZT-S/araldite-F composites encompassing high stiffness (C33D ~ 23-60 GPa). \ud
The Pb-free LKNNT-AS-M/Epo-Tek 301 composites also exhibited the \ud
enhanced properties such as higher thickness factor kt ?63-67%, lower planar factor kp \ud
?27-34%, higher kt/kp ratio ?2.3, low electrical (tan? ?0.027) and mechanical (Qm ?9) \ud
losses, encouraging acoustic impedance Z ?4.2-7.8Mrayl and ?5 times higher voltage \ud
coefficient g33 compared to LKNNT-AS-M piezoceramic. Likewise, the underwater \ud
results revealed that the transducer with 1-3 PZT-S/araldite-F sample exhibited better \ud
voltage receiving sensitivity Sh (-214dB ref 1V/µPa) due to its ?295% higher piezoelectric voltage coefficient gh (30×10-3Vm/N) compared to PZT-S. The above \ud
mentioned promising results of the developed composites indicate that they have the \ud
potential to be used as active elements in high performance ultrasonic transducers
