Time-sharing System Research Articles

Origin & History of ASP SaaS, PaaS and Cloud Computing

This research paper outlines the evolution of cloud computing and software-as-a-service (SaaS) from their origins in 1960s time-sharing systems to microkernel based systems in the late 1980’s. It traces key developments during the period from 1987 to 1988 including the emergence of an Application Service Provider system. It uses methods and models to confirm accuracy of these claims. The paper highlights how the simple migration from mainframe to microkernels overcame the limitations of adoption by the public, ultimately leading to the dominance of SaaS and PaaS as primary models for delivering software and ASP services. This progression represents in a shift towards more flexible, scalable, and accessible computing models that are delivered by services models, by network with management platforms for software as a service (SaaS), platforms as a service (PaaS) and infrastructure as a service (IaaS) customization.

Dynamic round robin with adaptive time quanta (DRRATQ): A proposed algorithm

The CPU scheduling technique influences the performance and efficiency of operating systems. Round-robin scheduling algorithm is ideal for time-shared systems, but it is not optimal for real-time operating systems since it yields more context switching, longer waiting time, and high turnaround time. The performance of the algorithm is predominantly influenced by the designated time quantum; however, determining a suitable time quantum is extremely challenging. This paper presents a CPU scheduling algorithm that provides a better tradeoff between waiting time, turnaround time, response time, and number of context switch by using hypothesis-based quanta generation approach. It combines the CPU burst requirements of actual processes with some noisy data and plots them against the presumed CPU quanta to get quanta densities so that a polynomial regression model can fit the data points with the highest adjusted R-squared. Then applying some complex inferential statistic, the required quanta is obtained. The scheduling is dynamic in nature because it generates the next CPU quanta in reference to the quanta that have been used in the previous cycle with remaining CPU burst requirements of the process, and it is also adaptive in nature because, at each cycle, it uses ‘d’ (5, 5, 4, 3, 2) degree of freedom to calculate the Jarque-Bera Statistics to accept/reject the hypothesis. The algorithm is implemented in ‘R’ and the performance has been evaluated on a sample size of five processes with some noisy data which outperforms the conventional RR and significantly reduces the performance parameters mentioned above. Implementing this algorithm to a time-sharing or distributed environment will undoubtedly improve system performance and will help to avoid issues like thrashing, incorporate aging, CPU affinity, and starvation. Since the proposed algorithm is work-conservative, therefore can be implemented in network packet switching, statistical multiplexing, and real-time systems.

History of the CAL Timesharing System

The CAL Timesharing System (CAL TSS) was developed at the University of California at Berkeley between 1968 and 1971 to provide interactive computing for research and instruction. It ran on a mainframe computer, the Control Data Corporation 6400, and was one of the earliest systems to use capabilities for protection. Using our memories, archival records, and files preserved by McJones that are part of a donation to the Computer History Museum, we discuss the origin of the project, development of the software, and the brief experience using the system before it was shut down in May 1972.

Cloud service analysis using round-robin algorithm for quality-of-service aware task placement for internet of things services

Round-robin (RR) is a process approach to sharing resources that requires each user to get a turn using them in an agreed order in cloud computing. It is suited for time-sharing systems since it automatically reduces the problem of priority inversion, which are low-priority tasks delayed. The time quantum is limited, and only a one-time quantum process is allowed in round-robin scheduling. The objective of this research is to improve the functionality of the current RR method for scheduling actions in the cloud by lowering the average waiting, turnaround, and response time. CloudAnalyst tool was used to enhance the RR technique by changing the parameter value in optimizing the high accuracy and low cost. The result presents the achieved overall min and max response times are 36.69 and 650.30 ms for running 300 min RR. The cost for the virtual machines (VMs) is identified from $0.5 to $3. The longer the time used, the higher the cost of the data transfer. This research is significant in improving communication and the quality of relationships within groups.

Multi-objective optimal allocation of regional comprehensive energy considering electricity trading

In order to promote the coordination of various forms of energy resources such as electric energy, heat energy, and cold energy, and to achieve complementary and efficient use of different energy sources, a method for optimizing the allocation of the capacity of a regional comprehensive energy system that takes into account the trading of electric and thermal energy is proposed. The energy interaction costs of the system and the grid heat network are included in the total cost. The optimization goal is a multi-objective function that comprehensively considers system economics, environmental protection, reliability, and interactive power fluctuations. Based on the energy hub, the capacity of each energy supply equipment in the area is optimized. Time-sharing electricity price and typical daily system economic operation are solved by genetic algorithm. Finally, an example of a park is used to verify its effectiveness. The results show that the proposed method can effectively reduce the system cost and reasonably avoid the limitations caused by the single decision factors in the system planning stage, thus providing a reference for the actual system planning and design.

Time-Sharing Control Strategy for Multiple-Receiver Wireless Power Transfer Systems

The cross-coupling effect between the induction coils of a multiple-receiver wireless power transfer (MRWPT) system severely weakens its overall performance. In this paper, a time-sharing control strategy for MRWPT systems is proposed to reduce the cross-coupling between receiver coils. An active-bridge rectifier is introduced to the receivers to replace the uncontrollable rectifier to achieve synchronization of the time-sharing control. The synchronization signal generated by an active-bridge rectifier can be directly used to realize the synchronization of time-sharing control and hence saved the traditional zero-crossing point detection circuits for time-sharing circuits. Moreover, the proposed time-sharing system has the advantages of both operating under a resistance-matching condition and providing target output voltage for each receiver. Furthermore, a voltage control strategy was developed to provide both high efficiency and a target output voltage for each receiver. Finally, the simulation and experimental results show that the time-sharing MRWPT system reduced the cross-coupling effect between the receiver coils, and the voltage control strategy provided both a high efficiency and a target output voltage for each receiver.

Condomínios em Time-sharing: Responsabilidade Tributária e Solidariedade no IPTU e no ITR

This article analyzes the taxation of properties in the time-sharing system, concerning to the Brazilian legal system, with regard to the incidence of the urban property tax and the rural property tax. Initially, it starts with the historical and conceptual presentation about the time-sharing institute. Then, we proceed with the presentation of general aspects of the two taxes, and then proceed with the study of tax liability with regard to time-sharing, addressing the issue of solidarity, the central object of the work. The issue will also be addressed from the perspective of the principles of legality, equality, contributory capacity and the fundamental right to property. Finally, we proceed to the brief presentation of the issues related to the execution, in relation to the attachment of the immovable property subject to the condominium in timesharing.

面向运动目标探测的分时型红外偏振成像系统

面向运动目标探测的分时型红外偏振成像系统

Computational Psycholinguistics

Computational Psycholinguistics

A British Multi-Access System on an IBM System/360 Computer

Following the success of the Compatible Time-Sharing System [1], and its brilliant exploitation in Project MAC at MIT...

An efficient average execution time-round-robin (AET-RR) scheduling algorithm

Scheduling is a well known term in the field of operating system which allows processes for execution. Round-robin (RR) performs better in the time-shared system; as each process allows for execution within a specific time slot i.e time quantum (TQ). The effectiveness of RR scheduling depends on the value of TQ. For further performance enhancement, an efficient average execution time-round-robin (AET-RR) algorithm has been proposed for both online and offline scenario with varying TQ. Both the proposed algorithms (for online and offline) has been thoroughly explained through block diagram, flowchart and example. The experimental analysis shows that our proposed AET-RR algorithm performs better as compared to a conventional RR algorithm in terms of average turnaround time (ATAT), average waiting time (AWT) and number of context switch (NCS) with increasing burst time (BT).

A Novel Amended Dynamic Round Robin Scheduling Algorithm for Timeshared Systems

Central Processing Unit (CPU) is the most significant resource and its scheduling is one of the main functions of an operating system. In timeshared systems, Round Robin (RR) is most widely used scheduling algorithm. The efficiency of RR algorithm is influenced by the quantum time, if quantum is small, there will be overheads of more context switches and if quantum time is large, then given algorithm will perform as First Come First Served (FCFS) in which there is more risk of starvation. In this paper, a new CPU scheduling algorithm is proposed named as Amended Dynamic Round Robin (ADRR) based on CPU burst time. The primary goal of ADRR is to improve the conventional RR scheduling algorithm using the active quantum time notion. Quantum time is cyclically adjusted based on CPU burst time. We evaluate and compare the performance of our proposed ADRR algorithm based on certain parameters such as, waiting time, turnaround time etc. and compare the performance of our proposed algorithm. Our numerical analysis and simulation results in MATLAB reveals that ADRR outperforms other well-known algorithms such as conventional Round Robin, Improved Round Robin (IRR), Optimum Multilevel Dynamic Round Robin (OMDRR) and Priority Based Round Robin (PRR)

Onboard software of Plasma Wave Experiment aboard Arase: instrument management and signal processing of Waveform Capture/Onboard Frequency Analyzer

We developed the onboard processing software for the Plasma Wave Experiment (PWE) onboard the Exploration of energization and Radiation in Geospace, Arase satellite. The PWE instrument has three receivers: Electric Field Detector, Waveform Capture/Onboard Frequency Analyzer (WFC/OFA), and the High-Frequency Analyzer. We designed a pseudo-parallel processing scheme with a time-sharing system and achieved simultaneous signal processing for each receiver. Since electric and magnetic field signals are processed by the different CPUs, we developed a synchronized observation system by using shared packets on the mission network. The OFA continuously measures the power spectra, spectral matrices, and complex spectra. The OFA obtains not only the entire ELF/VLF plasma waves’ activity but also the detailed properties (e.g., propagation direction and polarization) of the observed plasma waves. We performed simultaneous observation of electric and magnetic field data and successfully obtained clear wave properties of whistler-mode chorus waves using these data. In order to measure raw waveforms, we developed two modes for the WFC, ‘chorus burst mode’ (65,536 samples/s) and ‘EMIC burst mode’ (1024 samples/s), for the purpose of the measurement of the whistler-mode chorus waves (typically in a frequency range from several hundred Hz to several kHz) and the EMIC waves (typically in a frequency range from a few Hz to several hundred Hz), respectively. We successfully obtained the waveforms of electric and magnetic fields of whistler-mode chorus waves and ion cyclotron mode waves along the Arase’s orbit. We also designed the software-type wave–particle interaction analyzer mode. In this mode, we measure electric and magnetic field waveforms continuously and transfer them to the mission data recorder onboard the Arase satellite. We also installed an onboard signal calibration function (onboard SoftWare CALibration; SWCAL). We performed onboard electric circuit diagnostics and antenna impedance measurement of the wire-probe antennas along the orbit. We utilize the results obtained using the SWCAL function when we calibrate the spectra and waveforms obtained by the PWE.

Response Time Distribution of a Class of Limited Processor Sharing Queues

Processor sharing queues are often used to study the performance of time-sharing systems. In such systems the total service rate ?(m) depends on the number of jobs m present in the system and there is a limit implemented, called the multi-programming level (MPL), on the number of jobs k that can be served simultaneously. Prior work showed that under highly variable jobs sizes, setting the MPL k beyond the value k = arg maxm ?(m) may reduce the mean response time. In order to study the impact of the MPL k on the response time distribution, we analyse the MAP/PH/LPSk( m) queue. In such a queue jobs arrive according to a Markovian arrival process (MAP), have phase-type (PH) distributed sizes, at most k jobs are processed in parallel and the total service rate depends on the number of jobs being served. Jobs that arrive when there are k or more jobs present are queued. We derive an expression for the Laplace transform of the response time distribution and numerically invert it to study the impact of the MPL k. Numerical results illustrate to what extent increasing k beyond k? increases the quantiles and tail probabilities of the response time distribution. They further demonstrate that for bursty arrivals and larger MPL k values having more variable job sizes may reduce the mean response time.

Proportional Weighted Round Robin: A Proportional Share CPU Scheduler in Time Sharing Systems

Proportional Weighted Round Robin: A Proportional Share CPU Scheduler in Time Sharing Systems

An analysis of patents for anesthetic laryngoscopes

The anesthetic laryngoscope is one of the most popular medical tools for obtaining a clear view of the larynx and facilitates tracheal intubation. The number of anesthetic laryngoscope patents, coming mainly from the anesthesiologists, has rapidly increased. Each product has a specialized use for particular patients. However, it is unclear to what extent anesthetic laryngoscopy gained acceptance in operating theaters. By retrieving patent data for more than 90 countries from the Online Retrieval of Bibliographic Information Time-share (ORBIT) system, we reviewed the anesthetic laryngoscope patent literature published before July 6, 2015, and manually analyzed patent status, general development trends, areas of competition, technology patentees, and technology classifications. The study showed that the number of anesthetic laryngoscope patent applications has stayed at a high level in the last decade. Most patent activity was carried out in the USA, with China and a number of European countries trailing behind. In addition, the patent analysis provided an opportunity to understand the trends in the development of anesthetic laryngoscope technology, to identify shortcomings in clinical use of anesthetic laryngoscopes, to assist medical manufacturing specialists in improving the design and products, and to suggest to anesthesiologists modifications of the clinical signs of difficult tracheal intubation based on the new commercial anesthetic laryngoscopes applied in the front-line.

Computer Security Discourse at RAND, SDC, and NSA (1958-1970)

The 1967 Spring Joint Computer Conference session organized by Willis Ware and the 1970 Ware Report are widely held by computer security practitioners and historians to have defined the field's origin. This article documents, describes, and assesses new evidence about two early multilevel access, time-sharing systems, SDC's Q-32 and NSA's RYE, and outlines its security-related consequences for both the 1967 SJCC session and 1970 Ware Report. Documentation comes from newly conducted Charles Babbage Institute oral histories, technical literature, archival documents, and recently declassified sources on National Security Agency computing. This evidence shows that early computer security emerged from the intersection of material, cultural, political, and social events and forces.

Mobile-Edge Computing Versus The Internet?: Looking beyond the literal meaning of MEC

Discusses the concept of mobile edge computing (MEC). The theme itself seems to be within the IEEE comfort zone in the sense that it is about solutions in the network gear rather than external software that is indifferent to the topology of the connectivity (also known as the network). We're now shifting to a world of software that is independent of computing and networking gear. Perhaps the key word here is edge, as though the Internet was something wide apart and we had to cross a boundary to get to it. That is the modem model and why we use the term access the Internet rather than simply talk about interconnecting end points. The other term is mobile computing, as if computing, that is software, was not inherently mobile. At one point, mainframes, the gear we used to compute, were hard, and all but impossible to move, so it's understandable that we revel in the ability to tap into the power of computing wherever we are. Yet even in the days of time-sharing systems, we could use portable, simple terminals (connected typewriters) to allow us to tap into the power of computers wherever we were. The irony is that as devices have become more portable, we've become more tethered! Many applications are unable to work unless we have a connection to the rest of the world (also known as the Internet) or, loosely speaking, a connection to the Internet-very loosely speaking as I'm trying to explain that there isn't a place called the Internet.

Fernando Corbató: Time-Sharing Pioneer, Part 2

Fernando Corbató: Time-Sharing Pioneer, Part 2 Dag Spicer (bio) Fernando Corbató is likely best known for his work developing time-sharing operating systems. Early in his career, Corbató had a pioneering role in the development of both the Compatible Time-Sharing System (CTSS) and Multics at the Massachusetts Institute of Technology. The second in a two-part series, the following interview is based on an oral history conducted by Steven Webber for the Computer History Museum in February 2006. (For a full transcript, see the CHM archive: http://archive.computerhistory.org/resources/text/Oral_History/Corbato_Fernando/Corbato_Fernando_1.oral_history.2006.102658041.pdf.) Steven Webber: Let’s get back to the summer of 1963. You mentioned the Project MAC summer program. What’s the actual timeframe on Project MAC? Fernando Corbató: J.C.R. Licklider, who had once been a professor at MIT, was at Lincoln Laboratories and he got his hands on some computers there. He was fascinated with the programming experience and ended up going to BBN (Bolt, Beranek and Newman), where he wanted to build a time-sharing system. A lot of efforts were ongoing to create time-sharing systems then, including the Dartmouth time-sharing system. The BBN system had a four-person team: John McCarthy was one of them, primarily as an adviser, and Ed Fredkin and Shelly Boilen, along with Licklider. They tried to create a simple time-sharing system based on the DEC PDP-1 computer, which was the first of the minicomputers. Today we’d call it a personal computer, but it was still a relatively big box. They got that system going in approximately the summer of 1962. For a long time, they bragged that they were first until I pointed out to them that we had demonstrated ours in 1961, but these are small details. McCarthy was promoting time-sharing along with Licklider at BBN, and Licklider then got recruited by ARPA to embark on a program encouraging “man-machine interaction.” The story I heard was that the Cuban Missile Crisis in 1961 had shocked the Pentagon because they discovered that a lot of their information systems were practically unusable. They couldn’t get information fast enough, and they were crashing. It was just a mess. They were so shocked that they had such poor man-machine interaction with their computers, their communication systems, their databases, and the like that they wanted to start research to improve on this and get better tools for the military’s purposes. So after Lick got recruited he began to travel around trying to encourage people to embark on time-sharing, and he came to MIT to see if anybody was interested. Webber: Was this after you had already demonstrated CTSS? Corbató: I’m not sure. We were certainly about to demonstrate, but the key thing is that Bob Fano, myself, Doug Ross, and about a half dozen or so of us who were participants in the computing activities at MIT were at this meeting with Licklider. Licklider started to ask us what we wanted, what we would think about doing, but it was like a catfight. Everybody had his or her own notion or plan or scheme. Licklider took it in stride, but we were dismayed by our behavior in front of this potential sponsor who wanted to give us money to do something. We were so disorganized. It was disgraceful. Fano came back from that meeting and recognized that there was a lack of leadership at MIT. He thought about it and subsequently had a long train ride with Lick coming back from a meeting in Hot Springs, Virginia. I think Fano would claim that he was persuaded to go ahead when he came back from that meeting. He decided that he would start to organize a venture that came to be called Project MAC. That formative stage was in the fall of 1962. Bob made the decision that we would use CTSS as a prototype for Project MAC to exhibit time-sharing, and we would do that by getting a carbon copy of the machine at the Computation Center. I think they placed the order just around the turn of the year, 1962...

Fernando Corbató: Time-Sharing Pioneer, Part 2

Fernando Corbato is best known for his work developing time-sharing operating systems. Early in his career, Corbato had a key role in the development of both the Compatible Time-Sharing System (CTSS) and Multics at the Massachusetts Institute of Technology in the 1960s. This interview is the second in a two-part Annals series based on an oral history conducted by Steven Webber for the Computer History Museum in February 2006.