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Open access

Przemysław Czerniejewski, Kinga Zatoń, Natalia Kasowska and Adam Brysiewicz

Abstract

Monitoring studies of ichthyofauna, in particular non-indigenous species, are an important element of research on aquatic ecosystems. This information is essential for modelling population growth and predicting rates of expansion, quantifying ecological impacts and assessing the efficacy of removal and control strategies. Actually, the most compelling fish invasion in Polish freshwaters is arguably the accidental introduction of the topmouth gudgeon (Pseudorasbora parva). Age and lengths structure, condition factor and growth rate of the invasive populations of the topmouth gudgeon from small Polish rivers was examined. The samples were collected from the rivers: Molnica (n = 41), Myśla (n = 21) and Wardynka (n = 101) soon after the invasion was recorded (2017). Estimated ages of topmouth gudgeon ranged from 1+ to 3+ for the Myśla River, from 1+ do 4+ for the Molnica River, and from 1+ to 5+ for the Wardynka River. The fish from the Molnica River was characterised by the lowest total and standard length (TL, SL), weight, and highest condition. The results of back-calculations and the parameters of von Bertalanffy’s growth equation revealed distinct disproportions in the standard length (mm) in individual age groups (Molnica River: Lt = 54.94 [1 – e−0.68885 (1 − 0.003404)], Myśla River: Lt = 55.39 [1 – e−0.74921 (1 – 0.030962)], Wardynka River: Lt = 66.33 [1 – e−0.69348 (1 – 0.369505)]). The introduction of the topmouth gudgeon occurred in the upper and medium sectors of small rivers, but in subsequent years the species migrated to new sites further downstream and this may have affected the native ichthyofauna.

Open access

Michael Pace

Abstract

This non-experimental correlational study extends previous research investigating the relationship between project management methodology and reported project success, as well as the moderating variables of industry and project manager experience. The sample included North American project managers with five years’ experience, 25 years of age or older, and experience with multiple project management methodologies. The survey instrument consisted of 58 questions, utilizing a 5-point Likert scale to record responses. The survey contained three sections, including demographic information, questions related to a successful project, and questions related to a less-than successful (failed / challenged) project. 367 usable responses were received. The examination of the constructs included Pearson’s correlation coefficient as well as linear regression to determine the impact of moderating variables. Results indicated that project management methodology has a weak correlation with reported project success, and this correlation is not moderated by industry nor project manager experience. The results did not align with previously conducted studies, illustrating a need to continue the study of methods impacting success including investigating additional moderating variables.

Open access

Jaydeep Balakrishnan and Chun Hung Cheng

Abstract

Given the creation of different types of knowledge propositions in project and production management, we discuss what we call ‘evangelical’ propositions and what as knowledge intermediaries our role should be in its dissemination. We examine both proposition accuracy as well as the process by which the proposition was arrived at. We suggest strategies for knowledge intermediaries to adopt in order to achieve balance in evaluating these developments. Further, we support our suggestions by examining the development of the Theory of Constraints (TOC) and Critical Chain Project Management (CCPM) and the debate that has accompanied these, as a case study. The debate relates to how much of the knowledge proposition in these is really new and whether the method of developing the proposition was lacking in some sense. Knowledge intermediaries, those who are expected to play an important role in disseminating knowledge, will be better prepared to deal with similar innovations in a balanced manner, by analyzing the case of TOC/CCPM.

Open access

Chien-Ho Ko and Jiun-De Kuo

Abstract

Traditional formwork design processes entail considerable waste, increasing non-value-adding manpower costs and operational time. The purpose of this research is to use lean thinking in formwork design so as to enhance design correctness and eliminate waste through establishing a Lean Formwork Design Process. In the design process, the concurrent design concept is adopted to provide a visual communication platform for design team members using Building Information Modeling (BIM). Industry Foundation Classes (IFC) are used as a protocol for sharing design artifacts. Design correctness is established to review and correct design errors, thus allowing for the construction of an organizational learning environment. Finally, the Lean Formwork Design Process is conceptualized using stock-flow diagrams. A real case is used to validate the applicability of the proposed approach. Application results show that the proposed method can enhance design correctness and reduce manpower waste and operational time in formwork engineering. This study is one of the first to apply lean thinking to improve practices in formwork design.

Open access

Luli Hoxha and Cheryl McMahan

Abstract

The world population is aging rapidly. The United Nations listed aging as one of the main social transformations of the twenty-first century. Aging impacts project managers as well. The most prevalent form of discrimination in workplaces is age discrimination. This study evaluated how project managers’ age influences project success. The population was 108 active or former project managers working in Albania or Kosovo. By using quantitative analysis, it was demonstrated that project managers’ age did not significantly predict project success. Therefore, there is a need to increase awareness among employers, so older project managers are not discriminated based on age.

Open access

R. S. Abdulrahman, A. D. Ibrahim and P. G. Chindo

Abstract

For organizations to be successful, they should be committed in managing risk proactively and consistently throughout the project and equally important is the determination of the Risk Management Maturity (RMM) of organizations because it is the commencing point in the review of the current RM systems, practices, and culture of construction organisations. It was reported that construction organisations lack the knowledge of their capability to manage risk and as a result, JV projects continue to fail. Studies have identified, categorised and assessed risk associated with JV projects in their local and international context but no study has assessed the RMM of construction organisations in JV projects. Therefore, this study assessed the RMM of construction organisations in JV projects. The attributes and dimensions used to assess the RMM of construction organisations were identified from literature and used in the survey to collect data from respondents and subsequently analysed using the Fuzzy synthetic evaluation technique. Findings revealed that construction organisations undertaking JV projects are at the “defined maturity level” which means that these organisations only practice informal risk management and uses only qualitative risk assessment technique. The study recommends that further studies should focus on how to improve and move from the current RMM level of construction organisations to the next maturity level (managed and optimised).

Open access

Zahra Kahvandi, Ehsan Saghatforoush, Mohammad Mahoud and Christopher Preece

Abstract

The right selection of implementation system for projects in the construction industry is critical to achieve success. Integrated Project Delivery (IPD), is a comprehensive implementation system which has in recent years been seen to play an effective role in projects improved efficiency. Implementing an IPD system to resolve various problems of traditional systems is very important; however there are several barriers to its implementation. In addition, rooting and classifying the barriers is very significant in being able to resolve them. The aim of this study is the identification of barriers to IPD basically extracted from existing case studies. In this research, the meta-synthesis qualitative method is used for identifying and classifying the IPD barriers. The results are presented in a comprehensive table, and then are illustrated as a pattern by using macro concepts. This pattern is useful for presenting barriers to IPD. Identifying the barriers and resolving them are as important as identifying the benefits of IPD in creating motivation for construction industry owners. They also serve to provide the context for required predictions in implementing this approach in the construction industry.

Open access

Oleksandr Kvartenko, Larysa Sabliy, Nataliya Kovalchuk and Andriy Lysytsya

Abstract

The use of the biological method is promising for treating underground waters from iron compounds. Iron bacteria used in the process are widely spread in weak acidic and neutral underground waters containing iron ions (II), dissolved carbon dioxide and minimum concentrations of oxygen. The relevant direction of present-day biotechnology is the use of iron bacteria for treating underground waters. The goal of this research is to compare the efficiency of using the biological method for treating underground iron containing weak acidic and neutral waters under different conditions. As the test-objects, Gallionella and Lepthotrix iron bacteria were used. The sedimentation of bio-minerals was obtained from the washout waters of the biological deironing station. Calcium soda was used as an additional source of inorganic carbon for bacteria. As a result of the studies it is established that the use of the non-reagent method gives the possibility to achieve only 80% efficiency in removing iron compounds while the use of sodium carbonate results in increasing efficiency up to 93%. To determine the contribution of biological purification of ground water from iron compounds, the bacteria were inhibited with the preparation of polyhexamethylene guanidine (PHMG) chloride. It was found that inhibition of Gallionella and Lepthotrix led to the reduction of 50% of the iron removal effect. The mechanism was developed of inhibiting the process of iron bacteria metabolism by PHMG (polyhexamethylene guanidine). The new technology of arranging a block-module station for treating underground waters is proposed.