The Case Study for Diversity in Nuclear Plant Instrument and Control System

2011 ◽  
Vol 383-390 ◽  
pp. 4163-4168
Author(s):  
Tao Fang ◽  
Jin Song Hu ◽  
Dao Gang Lu ◽  
Zhi Yin Liu

This paper through describing the comparison between LingAo Phrase II ATWT and Tomari DAS (Diverse Actuation System) in some aspects which including function, structure, and so on. Through the comparison, the author finds the biggest difference between the systems is the manual analog devices are used in ATWT. And the author proves the full digital control system’s performance is used to defense the CCF (Common Cause Failure). Especially the Controller be detailed analyzed by FTA (Failure Tree Analysis) and unavailability, because of the controller’s important. At last the author proposes better solutions for coping with the requirement of the Defense in CCF.

Author(s):  
MARY ANN LUNDTEIGEN ◽  
MARVIN RAUSAND

This article presents a practical approach to reliability assessment of a complex safety instrumented system that is susceptible to common cause failures. The approach is based on fault tree analysis where the common cause failures are included by post-processing the minimal cut sets. The approach is illustrated by a case study of a safety instrumented function of a workover control system that is used during maintenance interventions into subsea oil and gas wells. The case study shows that the approach is well suited for identifying potential failures in complex systems and for including design engineers in the verification of the reliability analyses. Unlike many software tools for fault tree analysis, the approach gives conservative estimates for reliability. The suggested approach represents a useful extension to current reliability analysis methods.


2017 ◽  
Vol 11 (1) ◽  
pp. 63
Author(s):  
Andhika Ariadharma

Sales is a major activity in companies that need to be taken seriously, because with the sale of thecompany to earn a profit for the company's survival. Given the importance of sales activity within thecompany, it is necessary to control the sale as well. Sales activity should be planned and carried outeffectively and efficiently as possible in order to profit the company can achieve the optimum point,and the company can also handle and control the sales activity well in line with the growing companyand competition in the business world. In this study, the researchers conducted a case study usingdescriptive analysis research methodology of data collection is done by questionnaires, interviews,observation, and research literature. The method used to test the hypothesis is a statistical method ofSpearman Rank correlation. Based on the results of questionnaires and hypothesis testing is done, theresults obtained by calculating the percentage of 69.22% so it can be concluded that the InternalControl System Sales is designed PT INTI (Persero) is very influence on sales effectivitness.Keywords: Internal Control System Sales, Sales Effectivitness


2022 ◽  
Vol 166 ◽  
pp. 108812
Author(s):  
Vinay Kumar ◽  
Kailash Chandra Mishra ◽  
Pooja Singh ◽  
Aditya Narayan Hati ◽  
Mohan Rao Mamdikar ◽  
...  

Author(s):  
Masahide Nakamur ◽  
Hiroshi Igaki ◽  
Takahiro Kimura ◽  
Kenichi Matsumoto

In order to support legacy migration to the service-oriented architecture (SOA), this paper presents a pragmatic method that derives candidates of services from procedural programs. In the SOA, every service is supposed to be a process (procedure) with (1) open interface, (2) self-containedness, and (3) coarse granularity for business. Such services are identified from the source code and its data flow diagram (DFD), by analyzing data and control dependencies among processes. Specifically, first the DFD must be obtained with reverse-engineering techniques. For each layer of the DFD, every data flow is classified into three categories. Using the data category and control among procedures, four types of dependency are categorized. Finally, six rules are applied that aggregate mutually dependent processes and extract them as a service. A case study with a liquor shop inventory control system extracts service candidates with various granularities.


2019 ◽  
Vol 304 ◽  
pp. 04011
Author(s):  
Dario Belmonte ◽  
Matteo Davide Lorenzo Dalla Vedova ◽  
Gaetano Quattrocchi

Asymmetry limitation requirements between left and right wing flap surfaces play an important role in the design of the implementation of the secondary flight control system of modern airplanes. In fact, especially in the case of sudden breaking of one of the torsion bars of the flap transmission line, the huge asymmetries that can rapidly develop could compromise the lateral-directional controllability of the whole aircraft (up to cause catastrophic occurrences). Therefore, in order to guarantee the aircraft safety (especially during take-off and landing flight phase in which the effects of asymmetries could generate uncontrollable aircraft attitudes), it is mandatory to timely detect and neutralize these asymmetries. The current monitoring techniques generally evaluate the differential angular position between left and right surfaces and, in most the events, limit the Flaps Control System (FCS) asymmetries, but in severe fault conditions (e.g. under very high aerodynamic loads), unacceptable asymmetries could be generated, compromising the controllability of the aircraft. To this purpose, in this paper the authors propose a new active monitoring and control technique capable of detecting the increasing angular error between the different flap surfaces and that, after stopping the whole actuation system, acts on the portion of the actuation line still connected to the PDU to minimize the FCS asymmetries.


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