scholarly journals Atypical start-up experiments on pump as turbine

2021 ◽  
Vol 13 (11) ◽  
pp. 168781402110627
Author(s):  
Yu-Liang Zhang ◽  
Yan-Juan Zhao
Keyword(s):  
Static Pressure ◽  
Power Coefficient ◽  
Transient Performance ◽  
Test Rig ◽  
Transient Characteristics ◽  
Maximum Value ◽  
Start Up ◽  
Initial Stage ◽  
Evolution Characteristics ◽  
The Impact

At present, research on the characteristics of pumps as turbine (PATs) during the start-up process is still insufficient. To reveal the transient characteristics of a centrifugal PAT during the atypical start-up process, a test rig for the transient performance of the PAT was built; in addition, experiments on the transient hydraulic performance of three kinds of steady speed and three kinds of steady flow were conducted. Through these experiments, the evolution characteristics of the transient performance parameters of the PAT during the atypical start-up process were analyzed over time. Moreover, three dimensionless coefficients were employed to deeply reveal the transient characteristics of the PAT during atypical start-up. Results showed that the rise curves of flow rate and outlet static pressure exhibited shock phenomena. With the increase in the stable running speed after start-up, the impact phenomenon of the outlet static pressure presented a delayed trend. The dimensionless head and flow coefficients reached the maximum value at the initial stage of the atypical start-up process and then rapidly dropped to the minimum value before slowly rising to the final stable value. The dimensionless power coefficient had a maximum value at the initial stage of atypical start-up and then rapidly dropped to the final stable value.

scholarly journals Modeling of CO Accumulation in the Headspace of the Bioreactor during Organic Waste Composting

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1367
Author(s):  
Karolina Sobieraj ◽  
Sylwia Stegenta-Dąbrowska ◽  
Jacek A. Koziel ◽  
Andrzej Białowiec
Keyword(s):  
Carbon Monoxide ◽  
Organic Waste ◽  
Short Term ◽  
Surrounding Environment ◽  
Advanced Technologies ◽  
Maximum Value ◽  
Initial Stage ◽  
Co Concentration ◽  
The Impact ◽  
Co Concentrations

Advanced technologies call for composting indoors for minimized impact on the surrounding environment. However, enclosing compost piles inside halls may cause the accumulation of toxic pollutants, including carbon monoxide (CO). Thus, there is a need to assess the occupational risk to workers that can be exposed to CO concentrations > 300 ppm at the initial stage of the process. The objectives were to (1) develop a model of CO accumulation in the headspace of the bioreactor during organic waste composting and (2) assess the impact of headspace ventilation of enclosed compost. The maximum allowable CO level inside the bioreactor headspace for potential short-term occupational exposure up to 10 min was 100 ppm. The composting was modeled in the horizontal static reactor over 14 days in seven scenarios, differing in the ratio of headspace-to-waste volumes (H:W) (4:1, 3:1, 2:1, 1:1, 1:2, 1:3, 1:4). Headspace CO concentration exceeded 100 ppm in each variant with the maximum value of 36.1% without ventilation and 3.2% with the daily release of accumulated CO. The airflow necessary to maintain CO < 100 ppmv should be at least 7.15 m3·(h·Mg w.m.)−1. The H:W > 4:1 and the height of compost pile < 1 m were less susceptible to CO accumulation.

Clients' Expectations on Audit Judgments: A Note

2004 ◽  
Vol 16 (1) ◽  
pp. 63-74 ◽  
Author(s):  
Venkataraman M. Iyer ◽  
Dasaratha V. Rama
Keyword(s):  
Audit Quality ◽  
Financial Statements ◽  
Early Years ◽  
Relative Power ◽  
Client Perceptions ◽  
Audit Firm ◽  
Auditor Tenure ◽  
Start Up ◽  
Nonaudit Services ◽  
The Impact

Audited financial statements can be viewed as the product of negotiations between a company's management and its auditor. Relative power of these two parties is a major factor that determines the outcome of the negotiation. This study examines the impact of auditor tenure, importance of a client to an audit partner, nonaudit purchases, and prior audit firm experience of client personnel on client perceptions about their ability to persuade the auditor in the context of an accounting disagreement. We obtained responses to a survey from 124 CPAs in industry who are employed as CEOs, CFOs, controllers, or treasurers. Our results indicate that respondents from companies with short auditor tenures were somewhat more likely to indicate that they could persuade the auditor to accept their (client's) position in case of a disagreement. This finding is consistent with the argument that auditors are susceptible to influence in the early years as they are still in the process of recouping start-up costs, but is not consistent with concerns expressed by legislators and others that long auditor tenures will adversely affect audit quality. Respondents who believed their business was more important for the audit partner were also more likely to believe that they could persuade the auditor. However, the purchase of nonaudit services and prior audit experience were not related to client's perceptions about their ability to persuade the auditor.

scholarly journals Land Subsidence Estimation for Aquifer Drainage Induced by Underground Mining

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4658
Author(s):  
Artur Guzy ◽  
Wojciech T. Witkowski
Keyword(s):  
Environmental Impact ◽  
Land Subsidence ◽  
Field Data ◽  
Underground Mining ◽  
Small Scale ◽  
Aquifer System ◽  
Maximum Value ◽  
The Impact ◽  
Method Model ◽  
Impact Of Mining

Land subsidence caused by groundwater withdrawal induced by mining is a relatively unknown phenomenon. This is primarily due to the small scale of such movements compared to the land subsidence caused by deposit extraction. Nonetheless, the environmental impact of drainage-related land subsidence remains underestimated. The research was carried out in the “Bogdanka” coal mine in Poland. First, the historical impact of mining on land subsidence and groundwater head changes was investigated. The outcomes of these studies were used to construct the influence method model. With field data, our model was successfully calibrated and validated. Finally, it was used for land subsidence estimation for 2030. As per the findings, the field of mining exploitation has the greatest land subsidence. In 2014, the maximum value of the phenomenon was 0.313 cm. However, this value will reach 0.364 m by 2030. The spatial extent of land subsidence caused by mining-induced drainage extends up to 20 km beyond the mining area’s boundaries. The presented model provided land subsidence patterns without the need for a complex numerical subsidence model. As a result, the method presented can be effectively used for land subsidence regulation plans considering the impact of mining on the aquifer system.

scholarly journals The influence of cronyism on entrepreneurial resource acquisition

2021 ◽  
Author(s):  
Junfan Yu ◽  
Saskia De Klerk ◽  
Michael Hess
Keyword(s):  
Community Involvement ◽  
Private Property ◽  
Resource Acquisition ◽  
Property Development ◽  
Network Utilization ◽  
Start Up ◽  
Entrepreneurial Strategies ◽  
Staged Model ◽  
The Impact

AbstractThis research focuses on how entrepreneurs utilize cronyism to acquire resources. A case study method allowed us to explore three firms in the private property development industry in China. These firms uniquely cultivated cronyism and achieved distinctly different outcomes. Our findings highlight Chinese entrepreneurs in start-up ventures and later-stage enterprises employ cronyism. The underlying rationale for using cronyism have common and heterogeneous motivations. The similarity and distinguishing rationale also apply to the impact of cronyism. We also find two contingency working mechanisms for cronyism: entrepreneurial characteristics and a staged model for cronyism. With the firm’s growth, cronyism remains important, but firms with more community involvement outperform others. This research contributes to the theory on strategic network utilization for resource acquisition during entrepreneurial development stages. We investigate how entrepreneurial strategies can assist in adapting to the “rules of the game” while utilizing resources within the set contextual constraints.

scholarly journals Monitoring of the Impact of Lithium Nitrate on the Alkali–aggregate Reaction Using Acoustic Emission Methods

Materials ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 20
Author(s):  
Justyna Zapała-Sławeta ◽  
Grzegorz Świt
Keyword(s):  
Acoustic Emission ◽  
Initial Reaction ◽  
Lithium Nitrate ◽  
Acoustic Emission Method ◽  
Emission Method ◽  
Acoustic Activity ◽  
Initial Stage ◽  
Chemical Admixture ◽  
Different Characteristics ◽  
The Impact

The study analyzed the possibility of using the acoustic emission method to analyse the reaction of alkali with aggregate in the presence of lithium nitrate. Lithium nitrate is a chemical admixture used to reduce adverse effects of corrosion. The tests were carried out using mortars with reactive opal aggregate, stored under the conditions defined by ASTM C227. The acoustic activity of mortars with a corrosion inhibitor was referred to linear changes and microstructure of specimens in the initial reaction stages. The study found a low acoustic activity of mortars with lithium nitrate. Analysis of characteristic parameters of acoustic emission signals, combined with the observation of changes in the microstructure, made it possible to describe the corrosion processes. As the reaction progressed, signals with different characteristics were recorded, indicating aggregate cracking at the initial stage of the reaction, followed by cracking of the cement paste. The results, which were referred to the acoustic activity of reference mortars, confirmed that the reaction of opal aggregate with alkali was mitigated in mortars with lithium nitrate, and the applied acoustic emission method enabled the detection and monitoring of ASR progress.

Study on the Operation Model of Colleges Network Learning Propaganda and Public Opinion Guidance Based on the Internet

2013 ◽  
Vol 380-384 ◽  
pp. 2104-2108
Author(s):  
Chen Liang Li ◽  
Ming Xia Zhu
Keyword(s):  
Public Opinion ◽  
Information Science ◽  
Internet Technology ◽  
The Internet ◽  
C Language ◽  
Network Learning ◽  
Maximum Value ◽  
Network Transmission ◽  
The Impact ◽  
Important Significance

With the development of computer information science and technology, Internet has a large number of network propaganda and public opinion page every day. Through the network micro message and the micro-blog forwarding, network propaganda and public opinion have the impact on the development and stability of colleges, so the study network propaganda and public opinion has important significance for the development of colleges. Under this background, based on the computer Internet technology, the Internet erection of network propaganda guidance mode are analyzed, and compared with the fuzzy minimum production tree theory and the C language software, the network construction is verified. Finally the iterative process of finding the network transmission is relatively stable, after 800 iterative steps, numerical is slowly increasing, in which the maximum value is about 0.0001. The seven school propaganda is been as the minimum spanning of tree main network, its sum of weighted has been up to 1606.

How do social skills enable nascent entrepreneurs to enact perseverance strategies in the face of challenges? A comparative case study of success and failure

2014 ◽  
Vol 20 (6) ◽  
pp. 517-541 ◽  
Author(s):  
Wadid Lamine ◽  
Sarfraz Mian ◽  
Alain Fayolle
Keyword(s):  
Social Skills ◽  
New Technology ◽  
New Ventures ◽  
Nascent Entrepreneurs ◽  
Entrepreneurial Process ◽  
Ongoing Research ◽  
Content Type ◽  
Start Up ◽  
The Impact

Purpose – This paper seeks to advance ongoing research in entrepreneurial perseverance. While the concept of perseverance is not new, few researchers paid attention to behavioural persistence in the entrepreneurial context. The purpose of this paper is to explore the emergence of new technology based firms (NTBF) by focusing on the role of nascent entrepreneurs’ social skills in the meeting the changes of entrepreneurial perseverance. Design/methodology/approach – In this paper the authors study the start-up phase of entrepreneurial process. The authors opted for a longitudinal case study approach in order to enhance the knowledge on entrepreneurs’ social skills and perseverance. For triangulation purpose the data were gathered using four different information sources. The use of Nvivo8 as the data analysis tool helped to impose a discipline and structure which facilitated the extraction of core insights. Findings – This paper contributes to the understanding of the entrepreneurial perseverance in the context of new venture creation. Particularly, reading the entrepreneurial process through the lens of the perseverance strategies model (Van Gelderen, 2012) provided a way to identify and then to assess the impact of the social skills on the overall entrepreneurial perseverance and their combined impact on the performance of NTBF creation process. In doing so, the authors identify the impact of entrepreneurs’ social skills to deal with a series of entrepreneurial problems such as scarcity of resources, uncertainty and ambiguity and consequently their impact on the likelihood of survival for new ventures. The issues that arose mostly reflected the inherent complexity of technology transfer processes, the university and entrepreneurs’ diverging cultures, and the very characteristics of the start-up phase of NTBFs. The findings reveal how social skills impact the entrepreneurial paths and probable outcomes. Research limitations/implications – This paper contributes to the understanding of the entrepreneurial perseverance in the context of NTBF creation. The findings reveal how social skills and perseverance impact the entrepreneurial paths and probable outcomes. Practical implications – The paper has implications for entrepreneurial support mechanisms such as technology business incubators in helping them to improve the efficacy and efficiency of their assistance to entrepreneurs through the development of their skill-sets and perseverance and providing enabling networking. In addition, the research has implications for entrepreneurship education and training. Indeed, there is an urgent need to design and implement courses and programs aiming at developing soft skills in entrepreneurship. Originality/value – In exploring networking and issues of perseverance for nascent entrepreneurs operating in new technology-based sectors, which the authors consider as an under searched area in entrepreneurial literature.

Student entrepreneurship ecosystems at Australian higher education institutions

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Alex Maritz ◽  
Quan Nguyen ◽  
Sergey Ivanov
Keyword(s):  
Higher Education ◽  
Higher Education Institutions ◽  
Entrepreneurship Education ◽  
University Student ◽  
Content Type ◽  
Student Entrepreneurship ◽  
Start Up ◽  
Entrepreneurship Ecosystems ◽  
Start Ups ◽  
The Impact

PurposeDespite the significance, university student start-ups and student entrepreneurship ecosystems (SEEs) have been subject to little research. This study aims to apply a qualitative emergent enquiry approach to explore best practice SEEs in Australia, complimented by narratives from leading scholars in higher education institutions with the aim of delineating the integrative components of SEEs.Design/methodology/approachAdopting the entrepreneurial ecosystem framework and aligned to the social cognitive theory, this paper explores the components and dynamics of SEEs, contributing to an understanding of how such components can better support the growth, sustainability and success of student start-ups. The authors extend entrepreneurship research on social construction using narrative research.FindingsThe findings provide guidelines for researchers, entrepreneurship scholars and educators, entrepreneurship students, policymakers and practitioners to enhance the impact and success of university student start-ups by adopting a student ecosystem approach.Research limitations/implicationsThe narratives represent a limited number of universities with an opportunity for further research to empirically measure the impact and outcomes of SEEs. The research is exploratory, inherently conceptual and emergent, providing an opportunity for validation of narrative frameworks in future studies.Practical implicationsThe findings may assist university managers to be more aware of their own subconscious preferences to student entrepreneurship and start-up initiatives, which may be useful in refining their impact and offerings regarding a quest toward the entrepreneurial university.Social implicationsFrom social perspectives, the alignment of the components of SEE has the ability to enhance and shift the entrepreneurial mindset of entrepreneurship students, notwithstanding enhancement of intentionality and self-efficacy.Originality/valueThis is the first study of SEEs in Australia, highlighting the importance of the integration of entrepreneurship education programs, entrepreneurship education ecosystems, the entrepreneurial university and specific start-up initiatives such as university accelerators. Furthermore, students may enhance their entrepreneurial mindset by actively engaging in such ecosystems.

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