2,993 research outputs found
A NOVEL JOINT PERCEPTUAL ENCRYPTION AND WATERMARKING SCHEME (JPEW) WITHIN JPEG FRAMEWORK
Due to the rapid growth in internet and multimedia technologies, many new
commercial applications like video on demand (VOD), pay-per-view and real-time
multimedia broadcast etc, have emerged. To ensure the integrity and confidentiality of
the multimedia content, the content is usually watermarked and then encrypted or vice
versa. If the multimedia content needs to be watermarked and encrypted at the same
time, the watermarking function needs to be performed first followed by encryption
function. Hence, if the watermark needs to be extracted then the multimedia data
needs to be decrypted first followed by extraction of the watermark. This results in
large computational overhead. The solution provided in the literature for this problem
is by using what is called partial encryption, in which media data are partitioned into
two parts - one to be watermarked and the other is encrypted. In addition, some
multimedia applications i.e. video on demand (VOD), Pay-TV, pay-per-view etc,
allow multimedia content preview which involves âperceptualâ encryption wherein all
or some selected part of the content is, perceptually speaking, distorted with an
encryption key. Up till now no joint perceptual encryption and watermarking scheme
has been proposed in the literature.
In this thesis, a novel Joint Perceptual Encryption and Watermarking (JPEW)
scheme is proposed that is integrated within JPEG standard. The design of JPEW
involves the design and development of both perceptual encryption and watermarking
schemes that are integrated in JPEG and feasible within the âpartialâ encryption
framework. The perceptual encryption scheme exploits the energy distribution of AC
components and DC components bitplanes of continuous-tone images and is carried
out by selectively encrypting these AC coefficients and DC components bitplanes.
The encryption itself is based on a chaos-based permutation reported in an earlier
work. Similarly, in contrast to the traditional watermarking schemes, the proposed
watermarking scheme makes use of DC component of the image and it is carried out
by selectively substituting certain bitplanes of DC components with watermark bits.
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Apart from the aforesaid JPEW, additional perceptual encryption scheme, integrated
in JPEG, has also been proposed. The scheme is outside of joint framework and
implements perceptual encryption on region of interest (ROI) by scrambling the DCT
blocks of the chosen ROI.
The performances of both, perceptual encryption and watermarking schemes are
evaluated and compared with Quantization Index modulation (QIM) based
watermarking scheme and reversible Histogram Spreading (RHS) based perceptual
encryption scheme. The results show that the proposed watermarking scheme is
imperceptible and robust, and suitable for authentication. Similarly, the proposed
perceptual encryption scheme outperforms the RHS based scheme in terms of number
of operations required to achieve a given level of perceptual encryption and provides
control over the amount of perceptual encryption. The overall security of the JPEW
has also been evaluated. Additionally, the performance of proposed separate
perceptual encryption scheme has been thoroughly evaluated in terms of security and
compression efficiency. The scheme is found to be simpler in implementation, have
insignificant effect on compression ratios and provide more options for the selection
of control factor
Network parameters impact on dynamic transmission power control in vehicular ad hoc networks
International audienceIn vehicular ad hoc networks, the dynamic change in transmission power is very effective to increase the throughput of the wireless vehicular network and decrease the delay of the message communication between vehicular nodes on the highway. Whenever an event occurs on the highway, the reliability of the communication in the vehicular network becomes so vital so that event created messages should reach to all the moving network nodes. It becomes necessary that there should be no interference from outside of the network and all the neighbor nodes should lie in the transmission range of the reference vehicular node. Transmission range is directly proportional to the transmission power the moving node. If the transmission power will be high, the interference increases that can cause higher delay in message reception at receiver end, hence the performance of the network decreased. In this paper, it is analyzed that how transmission power can be controlled by considering other different parameter of the network such as; density, distance between moving nodes, different types of messages dissemination with their priority, selection of an antenna also affects the transmission power. The dynamic control of transmission power in VANET serves also for the optimization of the resources where it needs, can be decreased and increased depending on the circumstances of the network. Different applications and events of different types also cause changes in transmission power to enhance the reachability. The analysis in this paper is comprised of density, distance with single hop and multi hop message broadcasting based dynamic transmission power control as well as antenna selection and applications based. Some summarized tables are produced according to the respective parameters of the vehicular network. At the end some valuable observations are made and discussed in detail
Geo-Political Checkmate in the Indian Ocean Region: 21st Century Maritime Silk Road, Energy Security and Indo-US Nexus
The study intends to explore the connection between Chinaâs energy security, 21st Century Maritime Silk Road (MSR), and its anticipated impacts on Indo-US strategic perception in the Indian Ocean region. Chinaâs economic prosperity and industrial boom is fomenting different variables to upset the U.S. led world order. In the back drop of energy security as core national interest, Chinese leadership has exceptionally focused the maritime domain. In addition to this, for uninterrupted industrial growth, China  largely relies on energy imports that have turned its attention to the strategic value of the Sea lines of communication (SLOCs). However, Chinaâs newly emerged interests and subsequent investment in different sea ports along the oceanic supply chain of Indian Ocean is fuelling Indo-US strategic distrust in the region. The study concludes that Chinaâs carefully craftedMaritime Silk Road (MSR) is to challenge the status quo to protect its (China) core national interests in Indian Ocean The divergence of strategic interests in Indian Ocean is heralding a new multipart strategic competition that will transform the Indian Ocean into breeding ground for naval arm race. To understand the shifting geo political realities, the researchers used the Power Transition theory
Iterative CT reconstruction from few projections for the nondestructive post irradiation examination of nuclear fuel assemblies
The core components (e.g. fuel assemblies, spacer grids, control rods) of the nuclear reactors encounter harsh environment due to high temperature, physical stress, and a tremendous level of radiation. The integrity of these elements is crucial for safe operation of the nuclear power plants. The Post Irradiation Examination (PIE) can reveal information about the integrity of the elements during normal operations and offânormal events. Computed tomography (CT) is a tool for evaluating the structural integrity of elements non-destructively. CT requires many projections to be acquired from different view angles after which a mathematical algorithm is adopted for reconstruction. Obtaining many projections is laborious and expensive in nuclear industries. Reconstructions from a small number of projections are explored to achieve faster and cost-efficient PIE. Classical reconstruction algorithms (e.g. filtered back projection) cannot offer stable reconstructions from few projections and create severe streaking artifacts. In this thesis, conventional algorithms are reviewed, and new algorithms are developed for reconstructions of the nuclear fuel assemblies using few projections. CT reconstruction from few projections falls into two categories: the sparse-view CT and the limited-angle CT or tomosynthesis. Iterative reconstruction algorithms are developed for both cases in the field of compressed sensing (CS). The performance of the algorithms is assessed using simulated projections and validated through real projections. The thesis also describes the systematic strategy towards establishing the conditions of reconstructions and finds the optimal imaging parameters for reconstructions of the fuel assemblies from few projections. --Abstract, page iii
A Survey of Examination Phobia amongst Students at Secondary School Level
This paper focuses on exam phobia among students. Exam phobia is an irrational fear that leads to avoidance of the feared situation or object which in turn increases the severity of the phobia. The students having an excessive and unreasonable fear due to exam or the presence or anticipation of a horrible situation causes an anxiety. The sufferer realizes that the fear is irrational; and the avoidance or distress due to the stimuli causes impairment in functioning. Eleven (11) Districts (counties) of the province of the Punjab, Pakistan were taken through convenient sampling. Two public Secondary schools (one male and one female) were selected from each District from urban area randomly. Seventy students (35 students from Boys Secondary school and 35 from Girls Secondary school) of grade 9 from each District were selected randomly. The total sampling was 11Ăâ70=770 students. A questionnaire was developed to collect the data. Data was analyzed by using SPSS version 16.0. The intensity of exam phobia was found. A comparison was also made on gender bases by using t-test. The results showed that the students suffer from exam phobia to some extent. Furthermore the results revealed that the level of exam phobia in male and female students was same. Recommendations have been given on the basis of findings
Ethical Leadership and Employee Creative Performance: Discussing the mediating role of Employer Feedback Environment in Software Houses of Pakistan
Purpose:
The basic purpose of this study was to explore employee creative performance, the contextual issues in the form of the leaderâs style, and the feedback environment established by the leader in the Pakistani context. This study has presented a mechanism model for an understanding predictor of employee creative performance with the help of various theories.
Methodology:
Data was collected and analyzed from software houses registered in PSEB from 320 leader-employee dyads. Our research design was correlational. To reduce the common method biases, data was collected from two sources: leaders and their subordinates by sending the online questionnaire. To measure the uni-dimensionality and validity of construct EFA was performed through SPSS. Further, to assess the common method biases Heterotrait-Monotrait Ratio (HTMT) was used. SEM was used to compute, analyze, and prove relationships of proposed hypotheses and model fitness. CFA was used to confirm the theoretical measurement model, on AMOS 24 by using the rotated factor analysis.
Finding:
To sustain in this era of the competitive global business environment, organizations can stimulate employee creative performance by focusing on contextual and subjective variables. As per the findings, contextual factors like feedback environment associated with the leader regarding his style should be ethical, have a vital position in an organization for improving creative performance among employees. Specifically, the current study owns its justification and contribution to the literature and practical implications in various ways.
Conclusion:
The study indicates that the ethical style of leadership has a strong positive (+) association with the creative performance of employees as well as with the employer feedback environment. Also the employer feedback environment has partial mediation among ethical leadership and employee creative performance
Factors Affecting Cotton Production in Pakistan:Empirical Evidence from Multan District
This paper attempts to examine the factors affecting cotton production in Multan region using primary source of data. A sample of 60 small farmers, 25 medium and 15 large farmers was randomly selected from two Tehsils namely Multan and Shujabad of district Multan. The Cobb-Douglas Production Function is employed to assess the effects of various inputs like cultivation, seed and sowing, irrigation, fertilizer, plant protection, inter-culturing / hoeing and labour cost on cotton yield. The results depicted that seed, fertilizer and irrigation were found scarce commodity for all category of farmers in district Multan. The Cobb-Douglas Production Function results revealed that the coefficients for cultivation (0.113) and seed (0.103) were found statistically significant at 1 percent level. The Cost-Benefit Ratio for the large farmers was found higher (1.41) than that of small (1.22) and medium (1.24) farmers. There is a dire need to ensure the availability of these scarce inputs by both public and private sectors as these inputs were major requirement of the cotton crop.Cotton; Cobb- Douglas Production Function; Cost Benefit Ratio; Marginal Value Product; Allocate Efficiency of Critical Inputs; Multan District; Pakistan
Geotechnical characteristics of effluent contaminated cohesive soils
In developing countries like Pakistan, raw industrial effluents are usually disposed-off directly into open lands or in water bodies resulting in soil contamination. Leachate formation due to rainfalls in openly dumped solid waste also adds to soil contamination. In this study, engineering behavior of soils contaminated by two industrial effluents, one from paper industry (acidic) and another from textile industry (basic), has been investigated. Laboratory testing revealed significant effects of effluent contamination on engineering behavior of tested soils. Liquid limit, plasticity index, optimum moisture content and compression index of tested soils were found to increase with effluent contaminant, indicating a deterioration in the engineering behavior of soils. Whereas maximum dry density, undrained shear strength and coefficient of consolidation of the contaminated soils showed a decreasing trend. The dilapidation in engineering characteristics of soils due to the addition of industrial effluents could pose serious threats to existing and future foundations in terms of loss of bearing capacity and increase in settlement. Keywords: soil contamination, industrial waste, engineering behavior, effluent waste, leachate.
First published online: 28 Nov 201
Investigating Reading Challenges Faced by EFL Learners at Elementary Level
It is hard to ignore the importance of reading skills for desired proficiency in foreign languages. Reading can be beneficial for learners to immerse themselves in the target language and learn it efficiently. In EFL contexts like Saudi Arabia, learners face many challenges in reading skills. The main purpose of this research was to explore reading problems of elementary level students and causes of the readings skills inabilities. Following random and convenience sampling techniques; this mixed-method research obtained quantitative data from 290 elementary level students and qualitative data from nine teachers and supervisors. The analysis of quantitative data from the reading test and checklist and qualitative data retrieved from interviews suggests that students considerably perform relatively low in reading skills, and the main reasons are poor vocabulary, incorrect pronunciation, wrong spellings, slow reading pace, and flawed grammar. These five areas account for more than 90% of the challenges faced by learners in reading skills. Based on evidence from this research, we suggest that policymakers, teachers, and students should focus on these five areas for solving the issues related to reading skills. Although other avenues are essential, these items demand special attention to develop the reading skills of EFL learners in Saudi Arabia and elsewhere in the world.Keywords: Reading skill, Elementary level, Reading Pace, EFLÂ Â
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