Search results for: 2-associated r-Stirling numbers

Authors: Joo-Hyung Oh

Abstract:

The number of service users of 4G VoLTE (voice over LTE) using LTE data networks is rapidly growing. VoLTE based on all-IP network enables clearer and higher-quality voice calls than 3G. It does, however, pose new challenges; a voice call through IP networks makes it vulnerable to security threats such as wiretapping and forged or falsified information. And in particular, stealing other users’ phone numbers and forging or falsifying call request messages from outgoing voice calls within VoLTE result in considerable losses that include user billing and voice phishing to acquaintances. This paper focuses on the threats of caller phone number spoofing in the VoLTE and countermeasure technology as safety measures for mobile communication networks.

Keywords: LTE, 4G, VoLTE, phone number spoofing

Procedia PDF Downloads 432

Authors: Inkyu Kim, SangMan Moon

Abstract:

This IEEE 802.11b protocol provides up to 11Mbps data rate, whereas aerospace industry wants to seek higher data rate COTS data link system in the UAV. The Total Maximum Throughput (TMT) and delay time are studied on many researchers in the past years This paper provides theoretical data throughput performance of UAV formation flight data link using the existing 802.11b performance theory. We operate the UAV formation flight with more than 30 quad copters with 802.11b protocol. We may be predicting that UAV formation flight numbers have to bound data link protocol performance limitations.

Keywords: UAV datalink, UAV formation flight datalink, UAV WLAN datalink application, UAV IEEE 802.11b datalink application

Procedia PDF Downloads 392

Authors: Ladznar S. Laja, Rosalio G. Artes, Jr.

Abstract:

This paper introduced a graph polynomial relating convexity concepts. A graph polynomial is a polynomial representing a graph given some parameters. On the other hand, a subgraph H of a graph G is said to be convex in G if for every pair of vertices in H, every shortest path with these end-vertices lies entirely in H. We define the convex subgraph polynomial of a graph G to be the generating function of the sequence of the numbers of convex subgraphs of G of cardinalities ranging from zero to the order of G. This graph polynomial is monic since G itself is convex. The convex index which counts the number of convex subgraphs of G of all orders is just the evaluation of this polynomial at 1. Relationships relating algebraic properties of convex subgraphs polynomial with graph theoretic concepts are established.

Keywords: convex subgraph, convex index, generating function, polynomial ring

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Authors: K. C. Bloom, Cynde McInnis

Abstract:

The Covid-19 pandemic has caused immense changes in the way that we live, work and travel. The impact of these changes is readily apparent in tourism to Massachusetts and the region of New England. Whereas, in general, Massachusetts and New England are a hotspot for travelers from around the world, this form of travel has largely been shut down due to the pandemic. One such area where the impact has been felt is in marine-based wildlife tourism. Massachusetts is home to not only whales but also seals and great white sharks. Prior to the pandemic, whale watching had long been a popular activity while seal and shark tourism has been a developing one. Given that seeing a great white shark was rare in New England for many years, shark tourism has not played a role in the economies of the region until recently. While whales have steadily been found within the marine environments of Massachusetts and whale watching has been a popular attraction since the mid-1970s, the lack of great white sharks in New England was, in part, a response to a change in their environment in that a favorite food source, the gray seals, were culled by regional fishermen as the fishermen believed that seals were taking their catch. This retaliatory behavior ended when the Marine Mammal Protection Act of 1972 (MMPA) was passed. The MMPA prohibited the killing of seals and since then the seal population has increased to traditional numbers (Tech Times, 2014). Given the increase in the seal population in New England, and especially Cape Cod, Massachusetts, there has been a similar increase in the numbers of great white sharks. In fact, over the time between 2004 and 2014, the number of sightings increased from an average of two per year to more than 20 (NY Post, 7/21/14). This has increased even more over the last six years. As a result, residents and businesses in Massachusetts have begun to embrace the great whites as a potential tourism draw. Local business owners are considering opening up cage diving and shark viewing businesses while there has also been an increase in shark-related merchandise throughout the Cape Cod region. Combined with a large whale watching industry, marine-based wildlife tourism is big business to Massachusetts. With the Covid-19 pandemic shuttering international travel, this study aims to look at the impacts of the pandemic on this industry. Through interviews with marine-based wildlife tourism businesses as well as survey data collection from visitors, this study looks at the holistic impacts of the Covid-19 pandemic on an important part of the marine tourism industry in the state.

Keywords: marine tourism, ecotourism, Covid, wildlife

Procedia PDF Downloads 157

Authors: Michael Heuer, Ayoub Al-Hamadi, Alexander Rain, Marc-Michael Meinecke

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Vulnerable road users, e.g. pedestrians, have a high impact on fatal accident numbers. To reduce these statistics, car manufactures are intensively developing suitable safety systems. Hereby, fast and reliable environment recognition is a major challenge. In this paper we describe a tracking approach that is only based on a 24 GHz radar sensor. While common radar signal processing loses much information, we make use of a track-before-detect filter to incorporate raw measurements. It is explained how the Range-Doppler spectrum can help to indicated pedestrians and stabilize tracking even in occultation scenarios compared to sensors in series.

Keywords: radar, pedestrian detection, active safety, sensor

Procedia PDF Downloads 529

Authors: T. Padma, Jayashree S. Pillai

Abstract:

Random entities are an essential component in any cryptographic application. The suitability of a number theory based novel pseudorandom sequence called Pseudorandom Partial Quotient Sequence (PPQS) generated from the continued fraction expansion of irrational numbers, in cryptographic applications, is analyzed in this paper. An approach to build the algorithm around a hard mathematical problem has been considered. The PQ sequence is tested for randomness and its suitability as a cryptographic key by performing randomness analysis, key sensitivity and key space analysis, precision analysis and evaluating the correlation properties is established.

Keywords: pseudorandom sequences, key sensitivity, correlation, security analysis, randomness analysis, sensitivity analysis

Procedia PDF Downloads 590

Authors: Kim Kennedy, Daren Gibson, Stephanie Flukes, Chandra Diwakarla, Lisa Spalding, Leanne Pilkington, Andrew Redfern

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Introduction: Head and neck cancers (HNC) are often associated with the development of non-HNC primaries, as the risk factors that predispose patients to HNC are often risk factors for other cancers. Aim: We sought to evaluate whether there was an increased risk of smoking and alcohol-related cancers and also other cancers in HNC patients and to evaluate whether there is a difference between the rates of non-HNC primaries in Aboriginal compared with non-Aboriginal HNC patients. Methods: We performed a retrospective cohort analysis of 320 HNC patients from a single center in Western Australia, identifying 80 Aboriginal and 240 non-Aboriginal patients matched on a 1:3 ratio by sites, histology, rurality, and age. We collected data on the patient characteristics, tumour features, treatments, outcomes, and past and subsequent HNCs and non-HNC primaries. Results: In the overall study population, there were 86 patients (26.9%) with a metachronous or synchronous non-HNC primary. Non-HNC primaries were actually significantly more common in the non-Aboriginal population compared with the Aboriginal population (30% vs. 17.5%, p=0.02); however, half of these were patients with cutaneous squamous or basal cell carcinomas (cSCC/BCC) only. When cSCC/BCCs were excluded, non-Aboriginal patients had a similar rate as Aboriginal patients (16.7% vs. 15%, p=0.73). There were clearly more cSCC/BCCs in non-Aboriginal patients compared with Aboriginal patients (16.7% vs. 2.5%, p=0.001) and more patients with melanoma (2.5% vs. 0%, p value not significant (p=NS). Rates of most cancers were similar between non-Aboriginal and Aboriginal patients, including prostate (2.9% vs. 3.8%), colorectal (2.9% vs. 2.5%), kidney (1.2% vs. 1.2%), and these rates appeared comparable to Australian Age Standardised Incidence Rates (ASIR) in the general community. Oesophageal cancer occurred at double the rate in Aboriginal patients (3.8%) compared with non-Aboriginal patients (1.7%), which was far in excess of ASIRs which estimated a lifetime risk of 0.59% in the general population. Interestingly lung cancer rates did not appear to be significantly increased in our cohort, with 2.5% of Aboriginal patients and 3.3% of non-Aboriginal patients having lung cancer, which is in line with ASIRs which estimates a lifetime risk of 5% (by age 85yo). Interestingly the rate of Glioma in the non-Aboriginal population was higher than the ASIR, with 0.8% of non-Aboriginal patients developing Glioma, with Australian averages predicting a 0.6% lifetime risk in the general population. As these are small numbers, this finding may well be due to chance. Unsurprisingly, second HNCs occurred at an increased incidence in our cohort, in 12.5% of Aboriginal patients and 11.2% of non-Aboriginal patients, compared to an ASIR of 17 cases per 100,000 persons, estimating a lifetime risk of 1.70%. Conclusions: Overall, 26.9% of patients had a non-HNC primary. When cSCC/BCCs were excluded, Aboriginal and non-Aboriginal patients had similar rates of non-HNC primaries, although non-Aboriginal patients had a significantly higher rate of cSCC/BCCs. Aboriginal patients had double the rate of oesophageal primaries; however, this was not statistically significant, possibly due to small case numbers.

Keywords: head and neck cancer, synchronous and metachronous primaries, other primaries, Aboriginal

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Authors: Abobaker Abrahem M. Saad, Asma Abudasalam

Abstract:

The stem node segments were cultured on Murashige and Skoog (MS) medium. In the case of using MS+ Zeatin (1 mg/l), small shoot buds were formed directly in 70% of explants after 15 days, their length range between 0.1 to 0.3 cm after two weeks and reached 0.3 cm in length and three shoots in numbers after 4 weeks. When those small shoots were sub cultured on the same medium, they increased in length, number and reached 0.4 cm with 4 shoots, 0.4 cm with 5 shoots after six, eight and ten weeks respectively. In the case of using MS free hormones, MS+IAA (0.2mg/l) +BA (0.5mg/l), MS + kin(0.5mg/l), MS + kin (3mg/l) and MS +NAA (3mg/l) +BA (1mg/l), no sign of responses were noticed and only change in color in some cases. Different types of parenchyma cells and many layers of thick wall sclerenchyma cells were observed on MS+BA (1mg/l).

Keywords: Maerua, stem node, shoots, buds, In vitro

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Authors: Nur Irmawati, H. A. Mohammed

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In the present study, mixed convection in a horizontal rectangular duct using Al2O3 is numerically investigated. The effects of different Rayleigh number, Reynolds number and radiation on flow and heat transfer characteristics were studied in detail. This study covers Rayleigh number in the range of 2×106≤Ra≤2×107 and Reynolds number in the range of 100≤Re≤1100. Results reveal that the Nusselt number increases as Reynolds and Rayleigh numbers increase. It was also found that the dimensionless temperature distribution increases as Rayleigh number increases.

Keywords: numerical simulation, mixed convection, horizontal rectangular duct, nanofluids

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Authors: Fernando Ojedo, Alejandro Alvarez, Pedro Macizo

Abstract:

In the present study, we explored electrophysiological correlates of Arabic digits naming to determine semantic processing of numbers. Participants named Arabic digits grouped by category or intermixed with exemplars of other semantic categories while the N400 event-related potential was examined. Around 350-450 ms after the presentation of Arabic digits, brain waves were more positive in anterior regions and more negative in posterior regions when stimuli were grouped by category relative to the mixed condition. Contrary to what was found in other studies, electrophysiological results suggested that the production of numerals involved semantic mediation.

Keywords: Arabic digit naming, event-related potentials, semantic processing, number production

Procedia PDF Downloads 582

Authors: Behnaz Pahlousay, Farshad Kazemnejad, Elisa Palezzato, Michele Torielli

Abstract:

In this paper, we study the notions of connected domination number and of outer-connected domination number for middle graphs. Indeed, we obtain tight bounds for these numbers in terms of the order of the middle graph M(G). We also compute the outer-connected domination number of some families of graphs such as star graphs, cycle graphs, wheel graphs, complete graphs, complete bipartite graphs and some operation on graphs, explicitly. Moreover, some Nordhaus-Gaddum-like relations are presented for the outer-connected domination number of middle graphs.

Keywords: connected domination number, outer-connected dom- ination number, domination number, middle graph, nordhaus- gaddum-like relation.

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Authors: Qin-Min Ge, Shu-Ming Pan

Abstract:

Emergency clinicians usually get teaching qualification after graduating from medical universities without special faculty training in China mainland. Emergency departments are overcrowded places, with large numbers of patients suffering undifferentiated illness. In the field of emergency medicine (EM), improving the faculty competencies and developing the teaching skills are important for medical education, they could enhance learners outcomes and hence affect the patients prognosis indirectly. This article highlights the necessities of faculty training in EM, illustrates the qualities a good clinical educator should qualify, advances the skills as educators in an academic setting and discusses the ways to be good clinical teachers.

Keywords: emergency education, competence, faculty training, teaching, emergency medicine

Procedia PDF Downloads 596

Authors: Hani Alkayed, Belal Omar, Eileen Roddy

Abstract:

This study focuses on investigating the determinants of Corporate Social Responsibility Disclosure (CSRD) extent and quality in Jordan. The study examines factors that influence CSR disclosure extent and quality, such as corporate characteristics (size, gearing, firm’s age, and industry type), corporate governance (board size, number of meetings, non-executive directors, female directors in the board, family directors in the board, foreign members, audit committee, type of external auditors, and CEO duality) and ownership structure (government ownership, institutional ownership, and ownership concentration). Legitimacy theory is utilised as the main theory for our theoretical framework. A quantitative approach is adopted for this research and content analysis technique is used to gather CSR disclosure extent and quality from the annual reports. The sample is withdrawn from the annual reports of 118 Jordanian companies over the period of 2010-2015. A CSRD index is constructed, and includes the disclosures of the following categories; environmental, human resources, product and consumers, and community involvement. A 7 point-scale measurement was developed to examine the quality of disclosure, were 0= No Disclosures, 1= General disclosures, (Non-monetary), 2= General disclosures, (Non-monetary) with pictures, charts, and graphs 3= Descriptive/ qualitative disclosures, specific details (Non-monetary), 4= Descriptive/ qualitative disclosures, specific details with pictures, charts, and graphs, 5= Numeric disclosures, full descriptions with supporting numbers, 6= Numeric disclosures, full descriptions with supporting numbers, pictures, and Charts. This study fills the gap in the literature regarding CSRD in Jordan, and the fact that all the previous studies have ignored a clear categorisation as a measurement of quality. The result shows that the extent of CSRD is higher than the quality in Jordan. Regarding the determinants of CSR disclosures, the followings were found to have a significant relationship with both extent and quality of CSRD except non-executives, were the significant relationship was found just with the extent of CSRD: board size, non-executive directors, firm’s age, foreign members on the board, number of boards meetings, the presence of audit committees, big 4, government ownership, firm’s size, industry type.

Keywords: content analysis, corporate governance, corporate social responsibility disclosure, Jordan, quality of disclosure

Procedia PDF Downloads 230

Authors: Joo-Hyung Oh, Sekwon Kim, Myoungsun Noh, Chaetae Im

Abstract:

The number of service users of 4G VoLTE (voice over LTE) using LTE data networks is rapidly growing. VoLTE based on All-IP network enables clearer and higher-quality voice calls than 3G. It does, however, pose new challenges; a voice call through IP networks makes it vulnerable to security threats such as wiretapping and forged or falsified information. Moreover, in particular, stealing other users’ phone numbers and forging or falsifying call request messages from outgoing voice calls within VoLTE result in considerable losses that include user billing and voice phishing to acquaintances. This paper focuses on the threats of caller phone number spoofing in the VoLTE and countermeasure technology as safety measures for mobile communication networks.

Keywords: LTE, 4G, VoLTE, phone number spoofing

Procedia PDF Downloads 522

Authors: Kerkouri Abdelkadir

Abstract:

Numerical calculations of turbulent flows are one of the most prominent modern interests in various engineering applications. Due to the difficulty of predicting, following up and studying this flow for computational fluid dynamic (CFD), in this paper, we simulated numerical study of a flow past in a staggered tube bundle, using CFD Code ANSYS FLUENT with several models of turbulence following: k-ε, k-ω and SST approaches. The flow is modeled based on the experimental studies. The predictions of mean velocities are in very good agreement with detailed LDA (Laser Doppler Anemometry) measurements performed in 8 stations along the depth of the array. The sizes of the recirculation zones behind the cylinders are also predicted. The simulations are conducted for Reynolds numbers of 12858. The Reynolds number is set to depend experimental results.

Keywords: flow, tube bundle, ANSYS Fluent, CFD, turbulence, LDA, RANS (k-ε, k-ω, SST)

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Authors: R. Islam, Rafiqul A. Tarefder

Abstract:

This study investigates the effect of moisture conditioning on the Indirect Tensile Strength (ITS) of asphalt concrete. As a first step, cylindrical samples of 100 mm diameter and 50 mm thick were prepared using a Superpave gyratory compactor. Next, the samples were conditioned using Moisture Induced Susceptibility Test (MIST) device at different numbers of moisture conditioning cycles. In the MIST device, samples are subjected water pressure through the sample pores cyclically. The MIST conditioned samples were tested for ITS. Results show that the ITS does not change significantly with MIST conditioning at the specific pressure and cycles adopted in this study.

Keywords: asphalt concrete, tensile strength, moisture, laboratory test

Procedia PDF Downloads 380

Authors: Thomas Njuguna Kibutu

Abstract:

The ability to access justice is an important facet of securing peaceful, just, and inclusive societies, as recognized by Goal 16 of the 2030 Agenda for Sustainable Development. Goal 16 calls for peace, justice, and strong institutions to promote the rule of law and access to justice at a global level. More specifically, Target 16.3 of the Goal aims to promote the rule of law at the national and international levels and ensure equal access to justice for all. On the other hand, it is now widely recognized that Alternative Dispute Resolution (hereafter, ADR) represents an efficient mechanism for resolving disputes outside the adversarial conventional court system of litigation or prosecution. ADR processes include but are not limited to negotiation, reconciliation, mediation, arbitration, and traditional conflict resolution. ADR has a number of advantages, including being flexible, cost-efficient, time-effective, and confidential, and giving the parties more control over the process and the results, thus promoting restorative justice. The methodology of this paper is a desktop review of books, journal articles, reports and government documents., among others. The paper recognizes that ADR represents a cornerstone of Africa’s, and more specifically, Kenya’s, efforts to promote inclusive, accountable, and effective institutions and achieve the objectives of goal 16. In Kenya, and not unlike many African countries, there has been an outcry over the backlog of cases that are yet to be resolved in the courts and the statistics have shown that the numbers keep on rising. While ADR mechanisms have played a major role in reducing these numbers, access to justice in the country remains a big challenge, especially to the subaltern. There is, therefore, a need to analyze the opportunities and challenges facing the application of ADR mechanisms as tools for accessing justice in Kenya and further discuss various ways in which we can overcome these challenges to make ADR an effective alternative to dispute resolution. The paper argues that by embracing ADR across various sectors and addressing existing shortcomings, Kenya can, over time, realize its vision of a more just and equitable society. This paper discusses the opportunities and challenges of the application of ADR in Kenya with a view to sharing the lessons and challenges with the wider African continent. The paper concludes that ADR mechanisms can provide critical pathways to justice in Kenya and the African continent in general but come with distinct challenges. The paper thus calls for concerted efforts of respective stakeholders to overcome these challenges.

Keywords: mediation, arbitration, negotiation, reconsiliation, Traditional conflict resolution, sustainable development

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Authors: Isabel Roiz, Alejandra Cossio

Abstract:

This essay will talk about the problems of forced prostitution, human trafficking, and sexual exploitation in the Netherlands. This work conveys information from different sources stating the numbers and statistics of human trafficking throughout Europe and the different types of sexual exploitation as well as the means used for coercing victims into this illegal net. The research aims to inform and compare the way this business is handled and the ways used by criminals to lure and retain victims in spite of the law. It also tries to compare the laws in the Netherlands and Sweden regarding prostitution affects the illegal migration problems and how they change the ways those who work as prostitutes are treated. The aim of the paper is to take all of these aspects into consideration and reach a decision of what laws would most beneficiate the victims.

Keywords: human trafficking, prostitution, laws of migration, Amsterdam

Procedia PDF Downloads 348

Authors: Abdullah Al Faruque, Ram Balachandar

Abstract:

Series of laboratory tests were carried out to study the extent of scour caused by a three-dimensional wall jets exiting from a square cross-section nozzle and into a non-cohesive sand beds. Previous observations have indicated that the effect of the tailwater depth was significant for densimetric Froude number greater than ten. However, the present results indicate that the cut off value could be lower depending on the value of grain size-to-nozzle width ratio. Numbers of equations are drawn out for a better scaling of numerous scour parameters. Also suggested the empirical prediction of scour to predict the scour centre line profile and plan view of scour profile at any particular time.

Keywords: densimetric froude number, jets, nozzle, sand, scour, tailwater, time

Procedia PDF Downloads 435

Authors: Mark Kwaku Mensah Obeng

Abstract:

In the late 1990s and early 2000s, nationals of sub-Saharan Africa who had initially settled in the Middle East and other parts of south east Asia moved to Guangzhou in response to the 1997/8 Asian financial crisis in numbers never witnessed. They were later joined by many more as the Chinese economy improved and as the economic relationship between China and Africa improved. This paper tells the story of identifiable sets of Ghanaians in Guangzhou, China in the 21st century. It details out their respective characteristics and their activities in China, their migratory trajectories and the motivations for travelling to China. Also analyzed is how they are coping with life in the unknown destination. It finally attempt predicting the future of the Ghanaian community in China in terms of their level of community participation and integration.

Keywords: Africa in China, Ghana, motivation, Guangzhou

Procedia PDF Downloads 447

Authors: Suparman

Abstract:

This paper addresses the problem of the signal segmentation within a Bayesian framework by using reversible jump MCMC algorithm. The signal is modelled by piecewise constant Moving-Average (MA) model where the numbers of segments, the position of change-point, the order and the coefficient of the MA model for each segment are unknown. The reversible jump MCMC algorithm is then used to generate samples distributed according to the joint posterior distribution of the unknown parameters. These samples allow calculating some interesting features of the posterior distribution. The performance of the methodology is illustrated via several simulation results.

Keywords: piecewise, moving-average model, reversible jump MCMC, signal segmentation

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Authors: Sibel Özkan

Abstract:

This study aims to set forth the perception of young people in Turkey about “Gezi Parkı Actions” which has been represented by different views on social and traditional media. In-depth interview method was carried out with all of the participants who consisted of high school students. All interviews has been conducted in areas where the actions take place and the numbers of participants who are using and not using social media were equal. There are minor differences between young people who are using and not using social media. Participants who are not using social media had an opinion only about saving nature aspect of Gezi Parkı Actions. On the other hand, people who are using social media had another reasons such as freedom of expression, respect to the lifestyles etc. to join Gezi Parkı Actions. It was found that young people do not completely trust traditional media anymore.

Keywords: Gezi Parkı, resistance, social media, hegemony

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Authors: L. A. Jennings

Abstract:

Traditional sports media marginalizes or ignores female athletes in their coverage despite increasing numbers of female participation in professional sports. However, in venues in which women and men compete in the same event, such as fighting sports, media coverage of female athletes increases dramatically. Focusing on fighting sports, including boxing, submission wrestling, kickboxing, and Mixed Martial Arts, this paper demonstrates that inclusive venues provide an avenue for female athletes to receive equitable promotion, media coverage, and sponsorship opportunities using data from ESPN, Neilson, the Fan Report, and other emerging sources. This paper further argues that transgendered and nonbinary athletes could thrive in these environments in future sporting activities.

Keywords: sports, media, athletes, sports media, women in sports

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Authors: Pradyumna Mohanty

Abstract:

The paper aims to explore whether accounting information of Indian companies in the Steel sector are value relevant or not. Ohlson’s model which usually takes into consideration book value per share (BV) and earnings per share (EARN) has been used and the same has been expanded to include two more variables such as cash flow from operations (CFO) and return on equity (ROE). The data were collected from CMIE-Prowess data base in respect of BSE-listed steel companies and the time frame spans from 2010 to 2014. OLS regression has been used to test the value relevance of these accounting numbers. Results indicate that both CFO and BV are having significant influence on the stock price in two out of five years of study. But, BV is emerging as the most significant and highly value relevant of all the four variables during the entire period of study.

Keywords: value relevance, accounting information, book value per share, earnings per share

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Authors: M. Khalid, G. N. Singh

Abstract:

In this paper, we have considered the problem of estimation for population mean, on current (second) occasion in the presence of random non response in two-occasion successive sampling under two phase set-up. Modified exponential type estimators have been proposed, and their properties are studied under the assumptions that numbers of sampling units follow a distribution due to random non response situations. The performances of the proposed estimators are compared with linear combinations of two estimators, (a) sample mean estimator for fresh sample and (b) ratio estimator for matched sample under the complete response situations. Results are demonstrated through empirical studies which present the effectiveness of the proposed estimators. Suitable recommendations have been made to the survey practitioners.

Keywords: successive sampling, random non-response, auxiliary variable, bias, mean square error

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Authors: T. Zhou, S. F. Mohd Razali, Y. Zhou, H. Wang, L. Cheng

Abstract:

The wake flow behind two yawed side-by-side circular cylinders is investigated using a three-dimensional vorticity probe. Four yaw angles (α), namely, 0°, 15°, 30° and 45° and two cylinder spacing ratios T* of 1.7 and 3.0 were tested. For T* = 3.0, there exist two vortex streets and the cylinders behave as independent and isolated ones. The maximum contour value of the coherent stream-wise vorticity is only about 10% of that of the spanwise vorticity. With the increase of α, increases whereas decreases. At α = 45°, is about 67% of. For T* = 1.7, only a single peak is detected in the energy spectrum. The span-wise vorticity contours have an organized pattern only at α = 0°. The maximum coherent vorticity contours of and for T* = 1.7 are about 30% and 7% of those for T* = 3.0. The independence principle (IP) in terms of Strouhal numbers is applicable in both wakes when α< 40°.

Keywords: circular cylinder wake, vorticity, vortex shedding, side-by-side

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Authors: A. Youseef

Abstract:

One of the most aims of IEEE 802.16 (WiMAX) is to present high-speed wireless access to cover wide range coverage. The base station (BS) and the subscriber station (SS) are the main parts of WiMAX. WiMAX uses either Point-to-Multipoint (PMP) or mesh topologies. In the PMP mode, the SSs connect to the BS to gain access to the network. However, in the mesh mode, the SSs connect to each other to gain access to the BS. The main components of QoS management in the 802.16 standard are the admission control, buffer management, and packet scheduling. There are several researches proposed to create an efficient packet scheduling schemes. Therefore, we use QualNet 5.0.2 to study the performance of different scheduling schemes, such as WFQ, SCFQ, RR, and SP when the numbers of SSs increase. We find that when the number of SSs increases, the average jitter and average end-to-end delay is increased and the throughput is reduced.

Keywords: WiMAX, scheduling scheme, QoS, QualNet

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Authors: Norezzine Abdelaziz, Rebouh Nazih Yacer, Kezimana Parfait, Parpura D. I., Gadzhikurbanov A., Anastasios Dranidis

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The genetic variation of Shvicezebuvides cattle from three different farms in the Tajikistan Republic was studied using 10 microsatellite markers (SSR). The trials were laid out using a multi- locus analysis system for the analysis of cattle microsatellite locus. An estimated genetic variability of the examined livestock is given in the article. The results of our SSR analysis as well as the numbers and frequencies of common alleles in studied samples, we established a high genetic similarity of studied samples. These results can also be furthermore useful in the decision making for preservation and rational genetic resources usage of the Tajik Shvicezebuvides cattle.

Keywords: genetic characteristic, frequencies of the occurrence alleles, microsatellite markers, Swiss cattle

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Authors: Nasser Y. Mahamoud, Pierre Dehombreux, Hassan E. Robleh

Abstract:

Industrial companies may be confronted with questions about their choice of maintenance policy. This choice must be guided by several numbers of decision criteria or objectives related to their production or service activities but also to their level of development and their investment prospects. A decision-support methodology to choose a maintenance policy (corrective, systematic or conditional preventive, predictive, opportunistic or not) is proposed to facilitate this choice using the main categories of the most important decision criteria. The different steps of this methodology are illustrated using theoretical case: identification of the different maintenance alternatives, determining the structure of the most important categories of the decision criteria, assessing the different maintenance policies on to the criteria by using an ordinal preference relation, and finally ranking the different maintenance policies.

Keywords: maintenance policy, decision criteria, decision-making process, AHP

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Authors: Azzedine Abdedou, Khedidja Bouhadef

Abstract:

The present study is an analysis of the forced convection heat transfer in porous channel with an oriented jet at the inlet with uniform velocity and temperature distributions. The upper wall is insulated when the bottom one is kept at constant temperature higher than that of the fluid at the entrance. The dynamic field is analysed by the Brinkman-Forchheimer extended Darcy model and the thermal field is traduced by the energy one equation model. The numerical solution of the governing equations is obtained by using the finite volume method. The results mainly concern the effect of Reynolds number, jet angle and thermal conductivity ratio on the flow structure and local and average Nusselt numbers evolutions.

Keywords: forced convection, porous media, oriented confined jet, fluid mechanics

Procedia PDF Downloads 382