Telephone Exchange System Research Articles

미디어에 재현된 전화교환원의 노동 경험과 젠더화

There has been growing interest in hidden subjects in the development of science and technology and it has been reflected not only in academic research but also in popular culture. This study focuses on the Netflix drama series <Cable Girls>, which features telephone operators who played an important role in the early days of telecommunication, and analyzed the labor experience of the telephone operator. In the late 1920s, the setting of the series, telephone operators were one of the few jobs women could have, and were an object of envy. However, the telephone exchange system at the time was still at infancy and was supplemented by women's emotional labor. In addition, low wages and strict labor regulations were applied. The labor had been gendered, standardized and often invisible. <Cable Girls> depicts the friendship and solidarity of women who want to live their lives independently through their jobs as telephone operators in this working environment. Despite the limitations of being a romance melodrama, <Cable Girls> has a special significance in that it describes the multi-layered aspect of telephone operator, re-examining the hidden labor of telephone operators.

Stability analysis of GI/GI/c/K retrial queue with constant retrial rate

We consider a finite buffer capacity GI/GI/c/K-type retrial queueing system with constant retrial rate. The system consists of a primary queue and an orbit queue. The primary queue has \(c\) identical servers and can accommodate up to \(K\) jobs (including \(c\) jobs under service). If a newly arriving job finds the primary queue to be full, it joins the orbit queue. The original primary jobs arrive to the system according to a renewal process. The jobs have i.i.d. service times. The head of line job in the orbit queue retries to enter the primary queue after an exponentially distributed time independent of the length of the orbit queue. Telephone exchange systems, medium access protocols, optical networks with near-zero buffering and TCP short-file transfers are some telecommunication applications of the proposed queueing system. The model is also applicable in logistics. We establish sufficient stability conditions for this system. In addition to the known cases, the proposed model covers a number of new particular cases with the closed-form stability conditions. The stability conditions that we obtained have clear probabilistic interpretation.

Formalization of Signaling System by Process Calculus

Software systems play an important role in social infrastructures, and in the public and private sectors, for example in core banking, enterprise resource planning systems, electronic medical record systems, telephone exchange systems, etc. In such fundamental systems, we desire not only correctness but also robustness. Formal methods, such as software verification, have focused on correctness rather than robustness. The Spice calculus, which was proposed by Nishizaki et al., is a calculus process which enables us to formalize and analyze the resistance of communication protocols against Denial-of-Service attacks. The key idea of the analysis is analyzing costs of initiators and responders in communication protocols. In this paper, we extend the target area of systems to be analyzed by the Spice calculus and describe a new analysis methodology for distributed systems. We demonstrate analysis of a telephone exchange system, as an example of our methodology. In this paper, we extend the target area of systems to be analyzed by the Spice calculus and show a new analysis methodology for distributed systems. We demonstrate analysis of a telephone exchange system, as an example of our methodology. We set up ISUP of Signaling System No. 7 as a target and formalized a simple telephone network based on it in the framework of the Spice calculus. We then analyzed its connection establishing process and computation cost consumed the connection establishment.

List Media: The Telephone Directory and the Arranging of Names

List Media: The Telephone Directory and the Arranging of Names

Embracing dynamic evolution in distributed systems

Distributed systems aren't only more widespread than they used to be, but they've become more critical than ever, having moved from client-server systems to multitier heterogeneous systems. Many of these applications - such as telephone exchange systems - must be operational 24 hours a day, so shutting them down isn't a viable option for administrators who must make systemwide changes. As a system becomes larger and more complex, the likelihood of defects increases, which means a greater number of required fixes. Studies have found that nearly half the software development effort in complex distributed systems is devoted to maintenance. Furthermore, the industry currently favors iterative and incremental development approaches over the traditional waterfall approach in software engineering to flexibly handle requirements and reduce project risks by deploying smaller changes. These changes are regular and predictable. So, how can we build distributed systems to handle these kinds of changes? The answer, we argue, is dynamic evolution. From a business perspective, dynamic evolution permits frequent upgrades, which reduces the time between releases. Dynamic evolution also enhances flexibility in implementing changes to unforeseen and fluctuating business requirements. Many specialized distributed systems will benefit from factoring dynamic evolution into their designs. We can easily achieve dynamic evolution in a component-based distributed system. The abstraction of components and their connectors facilitates system structures to accommodate changes.

Software maintenance during system testing: enhanced methods for the System X project

The author describes improvements introduced during 1986 to the development process for the System X project, a large-scale stored-program-control telephone exchange system. Attention is given to improvements within the system testing phase of the life cycle, in particular, the methods whereby subsystem developers provide solutions to software problems identified by the system testing engineers. Software maintenance can be performed either by fixing the software object code or by editing and recompiling the software source code. The adoption of the latter approach as the standard means of maintaining software during system testing has necessitated the generation of novel management, technical, and quality procedures. This approach is now also being applied to maintenance of the in-service product.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Recovery and Diagnostics in the Central Control of the AXE Switching System

AXE is a stored program controlled (SPC) telephone exchange system. Its control system typically comprises 100 000 IC packages with MTBF = 200 h. The application allows the control system to contribute to the system outage with only a few minutes per year. An ordinary telephone technician is able to maintain the system, mainly during normal working hours.

Functionally distributed telephone exchange control system using microprocessors

Functionally distributed telephone exchange system architecture is proposed based on information theoretical analysis of exchange process. A pilot model is implemented using commercially available microprocessors to investigate a future cost-effective system architecture involving microprocessor controlled telephone terminals.

Contact Behavior of Telephone Relays and Connectors in Various Aggressive Environments

Air pollution contributes to the degradation of the reliability of telephone switching relays. To study pollution effects on the French crossbar telephone exchange system we conducted three studies: first, atmospheric analysis in some telephone central offices; second, surface analysis of contacts from telephone exchanges; and, third, laboratory simulation tests in order to accelerate the harmful effects of natural exposure. This paper reports the methods used, and gives some results on the 'behavior of connectors and relays in some aggressive atmospheres.

Telephone Antiinterference Technique of the German Federal Post Office Telephone System

This paper presents function facilities for suppression of telephone lines and associated subscriber equipment. A setup of test combinations can be arranged by technical clerks at the centralized antiinterference station as well as by a field engineer. The present telephone technique is checked directly from the test desk via direct through-connected lines of the supervisory network. In special cases, remote-controlled measuring equipment and test devices are installed. In the new computerized local electronic telephone exchange system (EWSO 1), remote-controlled test circuits are used primarily, but only by means of trunk circuits of the telephone network. The ac voltages, the frequency of which is analog to the measured value, flow to the test desk via a speech channel and digital information via a data channel. Both facts are visual on the test desks panel The tester can use a service computer via a video data terminal and so be enabled to call from a subscriber index important data for testing a telephone connection. A special test unit can be called from subscriber's plant. This line is then partly checked by automatic steps and partly by dialing of recallable steps. Results are sent to a suppressor as a voicefrequency signal.

Electronic exchange system. Part 2: Control

The structure and low-level control equipment of an electronic telephone-exchange system are described in Pt. 1 of the paper. Pt. 2 expands the control to the higher levels of register and unique common control and describes the operation of the whole system. The main problem and objective of the control system is to be economical for all sizes of exchange, for which purpose its cost must be approximately proportional to the size of exchange with only a small constant cost independent of size. To this end, advantage is taken of the low cost, concomitant with the use of t.d.m. (time-division multiplex) switches, of guide-wire path selection and distributed processors to reduce the cost of the unique common processor, the cost of which is minimised by a combination of wired and stored-program logic, the stored-program-logic part being remotely located and shared with other exchanges if an exchange is too small to support it alone.

Trunking and traffic aspects of a sectionalised telephone exchange system

Sectionalisation is a principle of exchange design which requires the switching network to be divided into a number of sections, each with its own supervisory and selection apparatus. Each call has access to some or all sections and connection is completed by means of either intersectional or intrasectional links. A central control equipment determines which section is best able to deal with each call. It is shown that this enables a sectionalised exchange to use fewer crosspoints than the equivalent unsectionalised switching network.The paper describes the trunking of an electronically controlled reed-relay exchange system designed on these principles and gives details of the statistical studies conducted in the course of its development. Typical congestion formulas for different types of call are given. Traffic simulations with a digital computer confirmed that the theory is sufficiently accurate to serve as a basis for exchange design.

Time-division-multiplex electronic telephone exchange system for small pax

An experimental time-division-multiplex electronic telephone exchange on a 200-line 4-wire PAM (pulse amplitude modulation) system is described. The exchange is composed entirely of solid-state devices. The channel time is divided into four phases which are effectively used to reduce the number of circuit elements of the exchange. For reliable operation, common and multiplexed circuits are duplicated, and fault detection and change-over operation are explained.

The Highgate Wood experimental electronic telephone exchange system

An experimental public service telephone exchange is to be installed at Highgate Wood in North London. It has been developed in order to gain experience of the problems posed by introducing electronic exchanges into the public network. It meets a full and flexible facility schedule, and will test a variety of electronic time-sharing and commoncontrol techniques in the field.Speech and other signals are transmitted over unidirectional highways carrying 100 time-division-multiplex pulse channels. Each connection uses a pair of antiphase channels and is set up through line and inter-highway switches by storing channel pulses in magnetostriction delay lines. Delay lines also form the central feature of common register and supervisory equipments which, by operating with the channel pulses, control the setting up and progress of all calls. Common apparatus selects the channels to be used on all connections which are set up one at a time using information stored on magneticdrum tracks. Such information includes the directory number, meter record, state, class of service and type of each line, together with a library of translations required to route calls over junctions.A diversity of circuit techniques is included in the Highgate Wood exchange, which also incorporates security arrangements and maintenance aids to safeguard service to the subscriber, and to ease maintenance problems. The experience gained during the design, development, manufacture and trials of the system is expected to prove invaluable in progressing towards the telephone system of the future.

The application of square-loop ferrite material in data-processing systems

Digital computing systems using very small ferrite cores have been developed because of the rapidity with which data can be inserted or withdrawn. The paper describes other applications of ferrite material in data-processing systems, either as toroidal cores or as blocks which are subdivided into a number of independent cells by drilling holes through which the controlling circuit connections are threaded.One application takes the form of buffers for modifying the speed or mode of presentation of data; a second concerns counters, distributors and scalers, and, as an example of such requirements, an incoming line terminal for a telegraph exchange is quoted.Attention is directed to the possibility of using a ferrite selector and a ferrite store for electronic telephone-exchange systems employing time division. In both these applications speed is of importance. In the case of dial registers, it is explained that substantial economy can be derived from rapid processing of the data. The application to telephone-message accounting is also described. It is shown that magnetic material can be used to replace electromagnetic switches, meters and relays and electronic triggers, counters and gates.

The development of telephone exchange systems

The development of telephone exchange systems

The orient turns to automatic telephones

MANY great poets of China repeatedly have described the beauty of Hangchow. It is the capital of the Province of Chekiang, one of the smallest but richest in the country. At one time its leading glory was the fame of its beautiful landscape, but the town now is winning a standing also through the increasing application of modern engineering. Among several developments the most recent and perhaps most important is the new automatic telephone exchange system which now serves the whole area.

The semi-automatic method of handling telephone traffic

It is the purpose of this paper to describe briefly the Clement automanual telephone exchange system, explain its principles, and show some of the results it has produced. For proper presentation, and in order to make necessary comparisons, the subject will be developed as follows:

The Semi-Automatic Method of Handling Telephone Traffic

It is the purpose of this paper to describe briefly the Clement automanual telephone exchange system, explain its principles, and show some of the results it has produced. For proper presentation, and in order to make necessary comparisons, the subject will be developed as follows:

Discussion on “Automatic telephone exchange systems”

Discussion on “Automatic telephone exchange systems”