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Number of results: 10
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Abstract

The implementation of processes comprising the overall project management consists in the use of various tools, methods and techniques depending on the type of the project. The knowledge of the industry and the characteristics of construction projects make it possible to select those which, on the one hand, will not cause difficulties for the contractors and on the other, will, in fact, constitute a necessary complement to the technical skills of the project manager. Construction companies face situations that have a profound impact on the failure of projects. Such occurrences include a large number of simultaneously implemented projects, the appointment of a person who knows the project mainly from the implementation side as the project manager, a failure to perform risk analysis and procedures that become irrelevant when deadlines are approaching. After reviewing the available construction projects, analysing the literature, consulting experts and making observations, the authors determined that the majority of difficulties and failures result from omissions or errors that take place during the project planning and implementation stages. The following paper outlines the selected elements of project management, whose application in construction projects may significantly affect their final success and the results obtained. It also includes an example of the use of modern management methods, which certainly include risk management methods. A utilitarian tool addressing the effects of risk analysis is a contingency plan. Contingency may be translated as eventuality, possibility and sometimes also as coincidence.
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Authors and Affiliations

Magdalena Kowacka
1
ORCID: ORCID
Dariusz Skorupka
2
ORCID: ORCID
Agnieszka Bekisz
1
ORCID: ORCID
Dominika Dudziak Gajowiak
1
ORCID: ORCID
Artur Duchaczek
1
ORCID: ORCID

  1. General Tadeusz Kosciuszko Military University of Land Forces, Faculty of Economics, Czajkowskiego St. 109, 51-147 Wroclaw, Poland
  2. Wrocław University of Science and Technology, Faculty of Civil Engineering, 27 WybrzezeWyspianskiego St., 50-370 Wroclaw, Poland
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Abstract

In recent years, power systems have been pushed to operate above their limits due to the increase in the demand for energy supply and its usage. This increase is accompanied by various kinds of obstructions in power transmission systems. A power system is said to be secured when it is free from danger or risk. Power systems security deals with the ability of the system to withstand any contingencies without any consequences. Contingencies are potentially harmful disturbances which occur during the steady state operation of a power system. Load flow constitutes the most important study in a power system for planning, operation, and expansion. Contingency selection is performed by calculating two kinds of performance indices; an active performance index (PIP) and reactive power performance index (PIV) for a single transmission line outage. In this paper, with the help of the Newton Raphson method, the PIP and PIV were calculated with DIgSILENT Power Factory simulation software and contingency ranking was performed. Based on the load flow results and performance indexes, the Ethiopian Electric Power (EEP) North-West region network is recommended for an upgrade or the reactive power or series compensators should be constructed on the riskiest lines and substations.

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Authors and Affiliations

Dessalegn Bitew Aeggegn
Ayodeji Olalekan Salau
Yalew Gebru
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Abstract

The aim of this paper is to analyse and interprete the prose text "Vor der Zunahme der Zeichen" by the young, German-speaking writer who as a child fled from the civil war in Sri Lanka. The paper provides an analysis of the contingency of language signs (like homeland, descent, native language, identity) which is a function of the experience of flight, exile, and live in the globalized and electronic media-dominated world. The central role in the novel is played by the relation between death and literary language and its communicative and perception function.

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Authors and Affiliations

Anna Rutka
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Abstract

Finding the most critical contingencies in a power system is a difficult task as multiple evaluations of load and generation scenarios are needed. This paper presents a mathematical formulation for selecting, ranking, and grouping the most critical N-1 network contingencies, based on the calculation of a Power Constraint Index (PCI) obtained from the Outage Transfer Distribution Factors (OTDF). The results show that the PCI is only affected by the impedance parameter of the transmission network, the topology, and the location of all generators. Other methods, such as the Performance Index (PI) and the Overload Index (OL) are affected by the power generation and demand variations. The proposed mathematical formulation can be useful to accelerate the calculation of other methods that evaluate contingencies in power system planning and operation. Furthermore, the fast calculation of indices makes it suitable for online evaluation and classification of multiple events considering the current topology. The results showed that the proposed al- gorithm easily selected and ranked the expected contingencies, with the highest values of the index corresponding to the most critical events. In the filtering process, the computa- tional calculation time improved without losing the robustness of the results.
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Authors and Affiliations

Oswaldo Arenas-Crespo
John E. Candelo
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Abstract

In this paper voltage stability is analysed based not only on the voltage deviations from the nominal values but also on the number of limit violating buses and severity of voltage limit violations. The expression of the actual state of the system as a numerical index like severity, aids the system operator in taking better security related decisions at control centres both during a period of contingency and also at a highly stressed operating condition. In contrary to conventional N – 1 contingency analysis, Northern Electric Reliability Council (NERC) recommends N – 2 line contingency analysis. The decision of the system operator to overcome the present contingency state of the system must blend harmoniously with the stability of the system. Hence the work presents a novel N – 2 contingency analysis based on the continuous severity function of the system. The study is performed on 4005 possible combinations of N – 2 contingency states for the practical Indian Utility 62 bus system. Static VAr Compensator is used to improve voltage profile during line contingencies. A multi- objective optimization with the objective of minimizing the voltage deviation and also the number of limit violating bus with optimal location and optimal sizing of SVC is achieved by Particle Swarm Optimization algorithm.
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Authors and Affiliations

S.P. Mangaiyarkarasi
T. Sree Renga Raja
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Abstract

The paper presents methods of determining the location of cost buffers and corresponding contingency costs in the CPM schedule based on its work breakdown structure. Application of correctly located cost buffers with appropriately established reserve costs is justified by the common overrunning of scheduled costs in construction projects. Interpolated cost buffers (CB) as separate tasks have been combined with relevant summary tasks by the starttostart (SS) relationship, whereas the time of their execution has been dynamically connected with the time of accomplishment of particular summary tasks using the “paste connection” option. Besides cost buffers linked with the group of tasks assigned to summary tasks, a definition of the cost buffer for the entire project (PCB) has been proposed, i.e. as one initial task of the entire project. Contingency costs corresponding to these buffers, depending on the data that the planner has at his disposal, can be determined using different methods, but always depend on the costs of all tasks protected by each buffer. The paper presents an exemplary schedule for a facility and the method of determining locations and cost for buffers CB and PCB, as well as their influence on the course of the curve illustrating the budgeted cost of work scheduled (BCWS). The proposed solution has been adjusted and presented with consideration of the possibilities created by the scheduling software MS Project, though its general assumptions may be implemented with application of other similar specialist tools.

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Authors and Affiliations

M. Połoński
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Abstract

Henri Bergson as well as Gaston Milhaud undertake a radical critique of the conception of radical determinism because they both think that mind is able to act in a free and creative manner. In the article, I examine to what degree their arguments, aimed to prove this autonomy, converge. I inquire whether their endorsement of freedom of the mental acts led the two philosophers to the same conclusions regarding the cognitive extent of the intellect and therefore the parallel description of the status of scientific cognition.

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Authors and Affiliations

Elżbieta Walerich
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Abstract

Irrigation network maintenance is very important to ensure the function of irrigation run well. Therefore, maintenance fee is necessary to maintain the irrigation network. The problem is the maintenance cost of irrigation network is expensive, the second highest cost after rehabilitation costs. Thus, participation of farmers in irrigation network maintenance is essential. One of participation by farmers is in the form of regular fees. This study aims to determine the number of fees farmers are willing to pay to maintain irrigation networks through the willingness-to-pay approach. This study was conducted in the irrigation area of the Gonggang reservoir in Magetan District. The subject is farmers who use irrigation – the data collection technique used by observation, interview, questionnaire, and documentation. The data analysis technique used is the contingent valuation method with steps (1) determining the hypothetical market, (2) obtaining bids, (3) estimating average willingness to pay, (4) estimating bid curves, and (5) aggregating data. The result shows that the amount of farmers’ willingness to pay the maintenance fees for irrigation networks at Gonggang reservoir irrigation area in Magetan District by using the contingent valuation method is IDR 90,621 (USD 5.45) for each hectare for each planting period with total willingness to pay in the population of IDR 116,188,708 (USD 7,951.59) for each planting period.
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Authors and Affiliations

Cindy Puspitasari
1
ORCID: ORCID
Joko Sutrisno
1
ORCID: ORCID
Ernoiz Antriyandarti
1
ORCID: ORCID

  1. Universitas Sebelas Maret, Faculty of Agriculture, Study Program of Agribusiness, Jalan Ir. Sutami 36 57126 Surakarta, Central Java, Indonesia
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Abstract

This article asks the question to what extent Ryszard Nycz’s ambitious project of cultural practice outlined in his book Culture as Verb succeeds in opening up ‘a new form of knowledge’ and thus equipping the humanities with a fresh validity. Nycz takes up the poststructuralist concept of the humanities as a site of alternative or subversive knowledge, founded on the principles of interpretation and textual dispersion, and refocuses it on involvement (participation) and binary oppositions (borders), i.e. human vs. nonhuman, or nature vs. culture as a construct. The article, rather than addressing the issues of involvement and borders (liminality), concentrates instead on the contradictions that Nycz’ s theory gives rise to when applied to history, time and the emergence of subjectivity (identity). There is nothing objectionable about the proposition that temporal change is at the very core of culture, yet its locus must be sought not in the proclamations of individual agents, but in the conceptual ruptures that expose and reveal the boundaries of (collective) consciousness and unconsciousness, i.e. the operation of contingency.

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Authors and Affiliations

Jakub Momro
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Abstract

This article, focused principally on the exploration of contingency, the body and disgust in Michał Witkowski’s novel Margot, is also a polemic and a vindication of the book against the barrage of criticism it received from its reviewers. Most of them decided that Margot was a novel about nothing, a haphazard mix of sundry discourses devoid of any linear structure. In fact, several critics blamed the author of giving away both the narrative structure and the plot to capricious contingency. The article takes a fi rm stance against such charges and argues that contingency does not need to be seen as a fault at all. It lies at the heart of the novel and determines the actions of characters, but it plays as important a role in people’s lives outside fi ction. Analysing the ups and down of the main characters (Margot and Wadek Mandarynka), the article explains the function of emotions, the body, the characters’ language and their ideas of sacrum in the legitimization of contingency. A special role in this mechanism is played by disgust. Reactions of disgust are always contingent, or, as Julia Kristeva puts it the abject has the power to terrorize the subject to such extent that he can do nothing but to succumb to contingency. In working out the idea of the contingency of selfhood, the article also draws on Richard Rorty’s approach, and in particular his concept of ironism. The latter is used to classify the main character of Witkowski’s book as a consummate ironist, i.e. a person who tests different languages in which the world can be described in order to pursue his carnal desires. Finally, the article argues that in his novel Witkowski not only brings to light the fortuitous character of the postmodern identity but also creates a heterogeneous language to express it.

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Authors and Affiliations

Łukasz Wróblewski

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