Academic literature on the topic 'Cellular telephone calls'
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Journal articles on the topic "Cellular telephone calls"
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Joachim, Dale, and Eben Goodale. "On the use of cellular telephony for audio interaction with animals." Biology Letters 3, no. 6 (2007): 603–6. http://dx.doi.org/10.1098/rsbl.2007.0386.
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Playback is an important method of surveying animals, assessing habitats and studying animal communication. However, conventional playback methods require on-site observers and therefore become labour-intensive when covering large areas. Such limitations could be circumvented by the use of cellular telephony, a ubiquitous technology with increasing biological applications. In addressing concerns about the low audio quality of cellular telephones, this paper presents experimental data to show that owls of two species ( Strix varia and Megascops asio ) respond similarly to calls played through cellular telephones as to calls played through conventional playback technology. In addition, the telephone audio recordings are of sufficient quality to detect most of the two owl species' responses. These findings are a first important step towards large-scale applications where networks of cellular phones conduct real-time monitoring tasks.
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Redelmeier, Donald A., and Robert J. Tibshirani. "Association between Cellular-Telephone Calls and Motor Vehicle Collisions." New England Journal of Medicine 336, no. 7 (1997): 453–58. http://dx.doi.org/10.1056/nejm199702133360701.
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Wang, C. Jason, Alison A. Little, Jaime Bruce Holliman, et al. "Communication of Urgent Public Health Messages to Urban Populations: Lessons From the Massachusetts Water Main Break." Disaster Medicine and Public Health Preparedness 5, no. 3 (2011): 235–41. http://dx.doi.org/10.1001/dmp.2011.69.
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ABSTRACTObjective: To study when and how an urgent public health message about a boil-water order reached an urban population after the Massachusetts water main break.Methods: In-person surveys were conducted in waiting areas of clinics and emergency departments at a large urban safety net hospital within 1 week of the event.Results: Of 533 respondents, 97% were aware of the order; 34% of those who lived in affected cities or towns were potentially exposed to contaminated water. Among those who were aware, 98% took action. Respondents first received the message through word of mouth (33%), television (25%), cellular telephone calls (20%), landline calls (10%), and other modes of communication (12%). In multivariate analyses, foreign-born respondents and those who lived outside the city of Boston had a higher risk of exposure to contaminated water. New modes (eg, cellular telephones) were used more commonly by females and younger individuals (ages 18 to 34). Individuals who did not speak English at home were more likely to receive the message through their personal networks.Conclusions: Given the increasing prevalence of cellular telephone use, public officials should encourage residents to register landline and cellular telephone for emergency alerts and must develop creative ways to reach immigrants and non–English-speaking groups quickly via personal networks.(Disaster Med Public Health Preparedness. 2011;5:235–241)
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Englisher, Larry S., Richard D. Juster, Susan Bregman, David G. Koses, and Alicia Powell Wilson. "User Perceptions of SmarTraveler Advanced Traveler Information System: Findings from Second-Year Evaluation." Transportation Research Record: Journal of the Transportation Research Board 1537, no. 1 (1996): 63–69. http://dx.doi.org/10.1177/0361198196153700109.
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SmarTraveler was implemented as an operational test of an advanced traveler information system in the Boston metropolitan area. Users call the service from cellular or conventional telephones to receive realtime, route-specific traffic and transit information free of charge (except for any telephone company charges). Several evaluations were conducted since the service began in January 1993, to assess public acceptance of the information provided by SmarTraveler. Findings on user perceptions of and response to the program during its second year of operation, from April through December 1994, are summarized. Calling frequency increased during this period. Calls from cellular telephones made up 61 percent of the total calls received, even though cellular telephone callers were in the minority of the user population. Users were found to be quite satisfied with the service, especially in comparison with broadcast media traffic reports. In particular, they found SmarTraveler easy to use and were pleased with its availability on demand, its up-to-the-minute information, and its coverage of major routes. Two-thirds of current users said that SmarTraveler helped reduce anxiety. Although virtually all users said they would continue calling SmarTraveler in the future, users indicated substantial sensitivity to the potential imposition of a service fee.
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Sasongko, Anky Ismas. "Billing Management System Design for Cellular Phone Network Practicum Module 2.4 Ghz WiFi Transmission." Jurnal Jartel: Jurnal Jaringan Telekomunikasi 6, no. 1 (2018): 17–22. http://dx.doi.org/10.33795/jartel.v6i1.133.
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This study aims to design and build a VoIP billing server that is used for calculating the cost of telephone conversations and designing a VoIP practicum module for students.The research method was carried out by conducting literature studies, network design planning, device configuration, determination of billing parameters and VoIP call testing to determine call quality and VoIP billing function.The result of this thesis is a telephone billing system application that is used to calculate VoIP-based telephone costs and the softphone application as a telecommunications medium. Where the billing server is well configured with the softphone application, the softphone application uses the simcard as data verification provided by the admin. The results of testing the success of telephone charges when 2 clients make calls with an initial pulse of 100 Rupiah, the result is a calculation of 100% between manual calculations and program calculations. And when the test was carried out, making calls more than 2 clients produced different data between manual and program calculations with an average of 101.75, the program calculation was on manual calculation of 100.The results of this difference were only for the first and second callers, the next caller had the results which is the same as manual calculation.
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Englisher, Larry S., Susan Bregman, Stephen Pepin, and Alicia Powell Wilson. "Promoting Advanced Traveler Information Systems Among Cellular and Land-Line Phone Users: SmarTraveler Experience in Boston." Transportation Research Record: Journal of the Transportation Research Board 1588, no. 1 (1997): 63–69. http://dx.doi.org/10.3141/1588-08.
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In 1993 the SmarTraveler advanced traveler information system (ATIS) was introduced to travelers in the greater Boston area as part of an operational test jointly funded by FHWA and the Massachusetts Executive Office of Transportation and Construction. The service offers real-time, route-specific travel information by phone for major highways and public transit. During the 3-year test period from January 1993 to January 1996, service usage grew to nearly 60,000 calls per week, made by an average of more than 20,000 users. To achieve this growth, SmarTraveler was marketed to both cellular and land-line phone users using a variety of strategies over the course of the test. Evaluation and monitoring studies were commissioned to examine the degree to which users responded to SmarTraveler and the marketing program. The evaluation included extensive surveys of users and nonusers as well as tracking of calls and call frequency. The findings of the independent evaluation team on the success of various promotional efforts associated with the SmarTraveler operational test are presented. Overall, the marketing program aimed at the broad target market during the first 2 years appears to have been only partly successful in increasing the public’s level of awareness of SmarTraveler, in convincing its target market of SmarTraveler’s superiority to radio and TV travel reports, and in inducing trials. As a result of the second-year evaluation, changes were made to marketing and pricing during the third year of operation to target cellular telephone users. Further surveys were conducted to examine cellular telephone user response to these changes. SmarTraveler experienced a large increase in calls and users in the third year, especially in the cellular telephone market. Among the survey findings was that this market is quite price sensitive.
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Ramalingam, Mritha, S. J. Sultanuddin, N. Nithya, et al. "Light Weight Deep Learning Algorithm for Voice Call Quality of Services (Qos) in Cellular Communication." Computational Intelligence and Neuroscience 2022 (August 30, 2022): 1–8. http://dx.doi.org/10.1155/2022/6084044.
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In this paper, a deep learning algorithm was proposed to ensure the voice call quality of the cellular communication networks. This proposed model was consecutively monitoring the voice data packets and ensuring the proper message between the transmitter and receiver. The phone sends its unique identification code to the station. The telephone and station maintain a constant radio connection and exchange packets from time to time. The phone can communicate with the station via analog protocol (NMT-450) or digital (DAMPS, GSM). Cellular networks may have base stations of different standards, which allow you to improve network performance and improve its coverage. Cellular networks are different operators connected to each other, as well as a fixed telephone network that allows subscribers of one operator to another to make calls from mobile phones to landlines and from landlines to mobiles. The simulation is conducted in Matlab against different performance metrics, that is, related to the quality of service metric. The results of the simulation show that the proposed method has a higher QoS rate than the existing method over an average of 97.35%.
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Sarkar, Sheila, Alanna Martineau, Mohammad Emami, Mohammad Khatib, and Karen Wallace. "Aggressive Driving and Road Rage Behaviors on Freeways in San Diego, California: Spatial and Temporal Analyses of Observed and Reported Variations." Transportation Research Record: Journal of the Transportation Research Board 1724, no. 1 (2000): 7–13. http://dx.doi.org/10.3141/1724-02.
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The California Highway Patrol in San Diego County receives cellular telephone calls reporting unsafe driving. The content of the calls varies, with drivers complaining about speeding cars driving over 161 km/h (100 mph) and other drivers weaving and cutting off or tailgating. In some cases, the driving conditions were even more volatile with drivers describing harassment, assaults with a weapon, or running other vehicles off the road. There were about 1,987 reported incidents from the freeways of San Diego for the months of April, June, and September 1998. The information received by the dispatchers was tabulated and put into five different categories. Analyses indicated that 24.6 percent of the calls were for “Aggressive Driving 1” (speeding plus some other behavior, such as unsafe lane changes or passing); “Aggressive Driving 2” (weaving and cutting) was reported most frequently (27.1 percent of all calls); about 12.5 percent of the calls were for “Aggressive Driving 3” (tailgating); “Speeding Alone” calls comprised 19.8 percent of the total; and the rest were for “Road Rage” (16.1 percent). Of the 1,987 calls, 33 percent were generated on Interstate 5, the busiest and longest in the county, followed by Interstate 15, which accounted for 22 percent of the calls. The high number of calls can be attributed to the high average daily traffic volumes at each interchange and the longer interstate lengths. Similarly, Interstate 8 seemed to have a lower number of calls than expected, because the urban portion of the freeway is not as long and the remaining distance had fewer vehicles at each interchange. This was further corroborated and both volume and length were robustly correlated with the number of phone reports per freeway. Additionally, chi-square tests indicated that the time of the day and day of the week influenced the type and number of calls received.
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Setyawan, Hamim. "PENGUATAN EKONOMI PESANTREN MELALUI MANAJEMEN UNIT USAHA AIDITEL DI PONDOK PESANTREN API SYUBBANUL WATHON SECANG." PRIMA PORTAL RISET DAN INOVASI PENGABDIAN MASYARAKAT 3, no. 1 (2024): 66–72. http://dx.doi.org/10.55047/prima.v3i1.1069.
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This research uses a qualitative descriptive approach because the approach can easily obtain in-depth information. The basic impetus for choosing this method is to answer the role of the Aiditel business unit in developing the economy of the boarding school, data collection techniques through interviews are the techniques used by the author to obtain existing information, and the results of this study are that over time seeing the needs of students and walisantri in communicating so that a telephone shop appears and then from the telephone shop it develops to provide stationery, and until now it continues to develop until the times also make this Aiditel wartel not only provide cellular phones and stationery but also provide video calls via WhatsApp, then the finances from the results of this business are reported regularly to the leadership of the boarding school, which will then be combined with cooperatives and other business units which will be managed directly by Mrs. Nyai for the needs of infrastructure and other needs.
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Gopi, B., J. Logeshwaran, and T. Kiruthiga. "An Innovation in the Development of a Mobile Radio Model for a Dual-Band Transceiver in Wireless Cellular Communication." BOHR International Journal of Computational Intelligence and Communication Network 1, no. 1 (2022): 20–25. http://dx.doi.org/10.54646/bijcicn.004.
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A modern telephone can only be used if it is a dual-band transceiver. Also, an indispensable condition is the availability of Internet access. Modern cell phones can only be used for their intended purpose: making calls. Due to the fact that the operating system is preinstalled on devices, the list of possibilities for gadgets could be expanded almost indefinitely. So you can even do a full-fledged dual-band transceiver from a cell phone. In this paper, an innovation in the development of mobile radio models dual-band transceivers in wireless cellular communication is proposed. For the dual-band transceiver in the phone to work, you need an Internet connection. Progress in the development of technologies for mobile networks does not stand still, and with each new standard and technology for mobile networks, new opportunities for using the network open up for end subscribers. It is based on packet voice data transmission called push-to-talk.
Dissertations / Theses on the topic "Cellular telephone calls"
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Ho, Chi-Jui. "Call admission control in cellular networks." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/15730.
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Keung, Yik. "Dynamic threshold call admission control policy of multi-service wireless cellular networks : a statistical approach /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202004%20KEUNG.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004.<br>Includes bibliographical references (leaves 80-81). Also available in electronic version. Access restricted to campus users.
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Abidogun, Olusola Adeniyi. "Data mining, fraud detection and mobile telecommunications: call pattern analysis with unsupervised neural networks." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
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Huge amounts of data are being collected as a result of the increased use of mobile telecommunications. Insight into information and knowledge derived from these databases can give operators a competitive edge in terms of customer care and retention,<br />
marketing and fraud detection. One of the strategies for fraud detection checks for signs of questionable changes in user behavior. Although the intentions of the mobile phone users cannot be observed, their intentions are reflected in the call data which define usage patterns. Over a period of time, an individual phone generates a large pattern of use. While call data are recorded for subscribers for billing purposes, we are making no prior assumptions about the data indicative of fraudulent call patterns, i.e. the calls made for billing purpose are unlabeled. Further analysis is thus, required to be able to isolate fraudulent usage. An unsupervised learning algorithm can analyse and cluster call patterns for each subscriber in order to facilitate the fraud detection process.<br />
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This research investigates the unsupervised learning potentials of two neural networks for the profiling of calls made by users over a period of time in a mobile telecommunication network. Our study provides a comparative analysis and application of Self-Organizing Maps (SOM) and Long Short-Term Memory (LSTM) recurrent neural networks algorithms to user call data records in order to conduct a descriptive data mining on users call patterns.<br />
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Our investigation shows the learning ability of both techniques to discriminate user call patterns<br>the LSTM recurrent neural network algorithm providing a better discrimination than the SOM algorithm in terms of long time series modelling. LSTM discriminates different types of temporal sequences and groups them according to a variety of features. The ordered features can later be interpreted and labeled according to specific requirements of the mobile service provider. Thus, suspicious call behaviours are isolated within the mobile telecommunication network and can be used to to identify fraudulent call patterns. We give results using masked call data<br />
from a real mobile telecommunication network.
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Yilmaz, Nusrat. "Resource Management In Cellular Communication Networks With Subscriber Profile Prediction." Phd thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606274/index.pdf.
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In this study, a dynamic resource management and subscriber profile prediction scheme for mobile communication systems is presented. The aim is to achieve a high level of QoS for both handoff calls and new calls, while at the same time to improve the utilization of wireless network resources. The simultaneous satisfaction of these two actually conflicting interests will be thanks to two major key features. First, it will be due to the individual subscriber profile based prior information about handoff reservation requests that are provided by the mobile terminals. This information is based on the cell transition probabilities calculated by the mobile itself using collected information during past operations. Second, it will be due to a two-way approach implemented in the resource management processes. The two-way approach controls both the amount of reserved radio channels and the new call admission in a dynamic way, depending on the subscriber mobility and network traffic conditions.
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Hancox, Graham. "Factors affecting drivers willingness to engage with a mobile phone while driving." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/14754.
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This thesis investigates drivers willingness to engage with a mobile phone while driving. Many studies have looked into the effects on driving performance that can result from phone usage, but few studies have directly considered what can encourage or inhibit phone engagement behaviours in the first place. An initial exploratory study (Study 1) was conducted, for which a photo elicitation interview (N=20) was designed and implemented. This aimed to find the extent to which factors influencing phone use transferred from out of the car to the driving environment. In particular, the study aimed to explore whether the driving environment could be considered unique. The results indicated that the high demands placed on the driver by the road environment clearly distinguished it from the other environments and the reported propensity to use a phone seemed to reflect this. Only factors which either changed the level of attention required by the task, such as a change in task demand as a result of changes in the traffic environment, had any substantial influence on willingness to engage. Driving may not be unique in terms of the overall factors influencing phone use but it is unique in the extent to which this particular factor seems to have such a strong bearing on interaction. Building on findings from Study 1, that the demand and attention required seemed to influence willingness to engage, it was noted that Fuller s (2005) Task Capability Interface model would serve as a useful framework for the remainder of the thesis. This model suggests that driver behaviour is dictated by the level of task difficulty perceived; an interaction between task demand and capability. Therefore, the effects these two elements might have on willingness to engage with mobile phones while driving were tested separately in the two remaining studies. Previous research suggested that task demand should comprise a combination of roadway demand and the intended phoning task. Study 2, therefore, experimentally tested the extent to which road demand and phone function intended to be used influenced drivers decisions to engage with their phone. Participants (N=20) viewed video clips of real road environments of varying demand. Rating scales were used by participants to rate their willingness to engage with various phone functions according to the scenario they had just viewed. It was found both roadway demand and phone functionality affected willingness to engage with a mobile phone whilst driving. There was a higher propensity to engage in phone use in road environments perceived to have a lower demand and lower propensity to engage in phone use in the highest demand scenarios. Answering a call was the most likely function to be engaged with by the participants and sending a text message was the least likely. The final study investigated how capability (comprising both phone and driving capability) influenced willingness to engage. Participants (N=40) were required to drive in a simulator under two conditions, simulated low and high road demand. Their willingness to interact with their phones, when faced with a number of phone tasks, was then observed. It was found that driving capability had an effect on willingness to engage in high demand scenarios with the less capable, novice, drivers having a higher propensity to engage with placing a call, sending a text message and reading a text message than the more experienced drivers. Novice drivers were willing to engage with some functions on their phone at possibly inappropriate times. It was further found that, in the simulated low demand road environment, phone capability influenced willingness to engage, with those who were more capable at placing a call and sending a text message found to be more willing to engage with these functions. The research reported in this thesis represents the first attempt in the literature to study, in depth, the factors which can influence phone engagement behaviour while driving. Novel contributions include investigating if factors influencing phone use transferred from out of the car to the driving environment. Further novel contributions included whether the phone function and road demand interact to influence willingness to engage and whether capability can affect phone engagement behaviour while driving. Extending the model developed by Fuller, the thesis offers an original model that describes the factors affecting phone engagement behaviour while driving. Suggestions are proposed for how the findings presented in this thesis can effectively be used and how future work should build on these initial foundations.
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Lilith, Nimrod. "Reinforcement learning-based resource allocation in cellular telecommunications systems." 2005. http://arrow.unisa.edu.au:8081/1959.8/46306.
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The work in this thesis concerns the use of reinforcement learning solutions to re-source allocation problems in channelised cellular networks. The methodology of re-inforcement learning techniques was chosen for application to these problems due to its capability of finding efficient policies in a fully on-line, adaptable manner, without requiring specific environment models. All of the presented agent architectures are assumed to simultaneously learn and perform network control functions in a totally on-line and unsupervised manner, and agents are developed with a view to real-world implementability by focussing on techniques that have low resource requirements and make use of only local system information.
Books on the topic "Cellular telephone calls"
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Association, Telecommunications Industry. Uniform dialing procedures and call processing treatment for cellular radio telecommunications: TIA/EIA interim standard. Telecommunications Industry Association, 1995.
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Office, General Accounting. Telecommunications: FCC should include call quality in its annual report on competition in mobile phone services : report to the Honorable Anthony D. Weiner, House of Representatives. GAO, 2003.
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Safe Prisons Communication Act of 2009: Report of the Committee on Commerce, Science, and Transportation on S. 251. U.S. G.P.O., 2009.
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Mcclallen, Filomena. Simplify Cellular Network Concepts : Systematic Methods to Prepare and Analyze Call Detail Records: Understand Historical Cellular Telephone Data. Independently Published, 2021.
Find full textBook chapters on the topic "Cellular telephone calls"
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Fuke, Hidenori. "Structural Changes and Regulatory Challenges in Japanese Telecommunications." In Networking and Telecommunications. IGI Global, 2010. http://dx.doi.org/10.4018/978-1-60566-986-1.ch116.
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The structure of the telecommunications industry in Japan has been changing revolutionarily. The changes are observed in five phases: (1) development of competition into the local call market, (2) diffusion of broadband Internet and development of inter-platform competition, (3) rapid growth of cellular services and Internet access via cellular, (4) decline of POTS (plain old telephone service), and (5) structural changes from vertical integration to layered structure and development of media convergence. These changes require total review of the regulatory framework that was formed in the POTS era. In this chapter, I propose to review: (a) essential facilities regulation, (b) a universal service system, and (c) a flat-rate pricing system of the Internet to solve problems that are likely to distort the new industry structure and would stress the importance of a regulatory system that is competition, technology, and content neutral.
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Pawar, V. P., Bhagyashree Kunte, and Srinivas Tumuluri. "The Indian Telecom Distress." In Indian Business Case Studies Volume II. Oxford University PressOxford, 2022. http://dx.doi.org/10.1093/oso/9780192869388.003.0014.
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Abstract This case study is about stress and survival of telecom industry players. India’s telecommunication network is the second largest in the world by number of telephone user (for both fixed and mobile phone). The major players are Airtel, BSNL, Vodafone-Idea. If we look back in to the history Reliance communication launched in the telecom industry in the year 2002. Later on other global measure launched in India like Vodafone, Uninor, Docomo. Current scenario in the telecom industry—where we have disruption in the call charge prizing with lowest ever monthly rental launched by Jio (Mukesh Ambani group). After launch of Jio, the existing stabilize private player Airtel, Vodafone-Idea faced challenges of survival due to low AGR. This case will highlight policies that depart from telecom sector. They must reconsider or update in order to offer the best consumer experience and prizing war. This case will highlight telecom crisis. The department of telecommunication appears to be on the side of operators but survivors are still in trouble. The battle between Jio, Airtel, and Vodafone-Idea—it became very intense. Cellular Operators Association of India (COAI) came to Airtel and Vodafone Idea for support. The COAI warned Supreme Court that the telecom sector would turn into a monopoly if Jio allowed to behave on own wish without proper policies in place. However this did not go well with Jio and they shot off a letter to COAI talking about the sector. Jio said, ‘these operators anyways were not investing sufficiently in the sector and have been shedding crocodile tears by claiming financial stress for a long time now and have not shown any inclination to modernize the networks.’
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Heim, Michael. "VR 101." In Virtual Realism. Oxford University Press, 1998. http://dx.doi.org/10.1093/oso/9780195104264.003.0006.
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Today we call many things “virtual.” Virtual corporations connect teams of workers located across the country. In leisure time, people form clubs based on shared interests in politics or music, without ever meeting face-to-face. Even virtual romances flourish through electronic mail. All sorts of hybrid social realities have sprung up on fax machines and computers, cellular telephones and communication satellites. Yet most of these “virtual realities” are not, in the strict sense of the term, virtual reality. They are pale ghosts of virtual reality, invoking “virtual” to mean anything based on computers. A strong meaning of virtual reality, however, ties together these looser meanings. A certain kind of technology—“VR” for short—has become the model for a pervasive way of seeing things. Contemporary culture increasingly depends on information systems, so that we find virtual reality in the weak sense popping up everywhere, while virtual reality in the strong sense stands behind the scenes as a paradigm or special model for many things. The first step in virtual realism is to become clear about the meaning of virtual reality in the strong sense of the term. We need to be clear about using virtual reality as a model because the loose or weak sense of virtual reality grows increasingly fuzzy as the face value of the term wears down in the marketplace, where virtual reality sells automobiles and soap. Car manufacturers use virtual reality in television commercials: “Climb out of that virtual reality and test drive the real road car that stimulates all five senses!” Newspaper cartoons and entertainment parks pump the popularity of virtual reality. Products on CD-ROM bill their 3-D (three dimensional) graphics as “true virtual reality.” AT&T welcomes you into its “virtual world.” The term now belongs to the universal vocabulary. But movies and seasonal television shows should not stretch VR to a thin vapor. Because virtual reality belongs to an important part of the future, we need to understand it not only as an undercurrent affecting cultural developments but also as a powerful technology in its own right.