Interaction of Ships and Ocean Structures With Ice Loads and Stochastic Ocean Waves

2007 ◽  
Vol 60 (5) ◽  
pp. 246-289 ◽  
Author(s):  
R. A. Ibrahim ◽  
N. G. Chalhoub ◽  
Jeffery Falzarano
Keyword(s):  
Probabilistic Models ◽  
Research Work ◽  
Ocean Waves ◽  
Offshore Structures ◽  
Review Article ◽  
Future Research ◽  
Impact Loads ◽  
Floating Structure ◽  
Research Activities ◽  
Ice Loads

The influence of floating ice on the dynamic behavior of ships and offshore structures depends on many factors such as ice thickness and its relative speed with respect to the floating structure. The ice resistance to ship motion forms an essential problem in ship design and navigation. Furthermore, local or global ice loads acting on ocean systems are random and nonsmooth when impact interaction takes place. Impact loads on the bow of a ship navigating in solid ice may be modeled by a Poisson law. The measured stress amplitudes on the ship frame at the bow follow an exponential distribution. The nonhomogeneity and difference in ice microstructure, as well as the influence of salt and temperature, result in a great uncertainty in the ice strength. Therefore, the current review article aims at assessing the ice related problems encountered by offshore structures as well as by ships during their navigation. It also discusses the impacts of local and global ice loads on floating structures and reviews their existing probabilistic models. Moreover, this article covers the dynamic interaction of ice with flexible and rigid structures, and ships. In view of ice loads on marine systems, new design regulations have been introduced by international organizations that are involved in the design and building of ships as well as offshore structures. The ship stochastic stability and the first-passage roll stabilization problem associated with random ocean waves will also be described in an attempt to stimulate future research work dealing with ice impact loads. Moreover, due to the lack of research activities addressing the control problem of ships operating in icy waters, the current article will briefly discuss passive and active control schemes developed for controlling the ship roll motion. There are 529 references cited in this review article.

Scale Effect in Ice Flexural Strength

2019 ◽  
Vol 141 (5) ◽  
Author(s):  
Mohamed Aly ◽  
Rocky Taylor ◽  
Eleanor Bailey Dudley ◽  
Ian Turnbull
Keyword(s):  
Flexural Strength ◽  
Sea Ice ◽  
Probabilistic Models ◽  
Scale Effects ◽  
Offshore Structures ◽  
Bridge Piers ◽  
Freshwater Ice ◽  
Flexural Failure ◽  
Ice Loads ◽  
Ice Strength

Ice flexural strength is an important parameter in the assessment of ice loads on the hulls of ice-class ships, sloped offshore structures, and sloped bridge piers. While scale effects in compressive ice strength are well known, there has been debate as to the extent of scale effects in ice flexural strength. To investigate scale effects during flexural failure of both freshwater and saline ice, a comprehensive up-to-date database of beam flexural strength measurements has been compiled. The database includes 2073 freshwater ice beam tests with beam volumes between 0.00016 and 2.197 m3, and 2843 sea ice beam tests with volumes between 0.00048 and 59.87 m3. The data show a considerable decrease in flexural strength as the specimen size increases, when examined over a large range of scales. Empirical models of freshwater ice flexural strength as a function of beam volume, and of saline ice as function of beam and brine volumes have been developed using regression analysis. For freshwater ice, the scale-dependent flexural strength is given as: σf=839(V/V1)−0.13 For sea ice, the dependence of flexural strength has been modeled as: σ=1324(V/V1)−0.054e−4.969vb. Probabilistic models based on the empirical data were developed based on an analysis of the residuals, and can be used to enhance probabilistic analysis of ice loads where ice flexural strength is an input.

scholarly journals Promoting the Use of Reference Management Tools An Opportunity for Librarians to Promote Scientific Tradition

2021 ◽  
Vol 42 (1) ◽  
pp. 64-70
Author(s):  
Vishal D. Bapte ◽  
Supriya A. Bejalwar
Keyword(s):  
Academic Writing ◽  
Research Work ◽  
Scientific Work ◽  
Review Article ◽  
Review Of The Literature ◽  
Management Tools ◽  
Research Activities ◽  
The Common ◽  
Library Professionals

The scientific tradition entails that any scientific work needs to be cited if it is responsible for the development of further another research work. This review article discusses the role of library professionals in promoting Reference Management Tools (RMTs) amongst the teachers, students, and researchers to maintain the scientific tradition of citation management. Among the various citation management tools available, four exemplary tools have been discussed briefly. The review of the literature revealed that the users have mixed responses pertaining to the use of RMTs. Especially; the common experience in respect of quality usage is very low. The users seemed to have limited themselves to make use of RMTs for reference management instead of exploring all the options associated with it. An attempt has been made to highlight why and how librarians should promote RMTs in the academic environment. Since librarians are considered experts in the field of reference management, they must grab this opportunity to strengthen the profession. The article urges the library professionals to get expertise in using RMTs so as to promote them successfully for academic writing and research activities.

Transducer Qualification for Wave Impact Load Measurements Using Wedge Drop Tests

2015 ◽  
Author(s):  
Zhenjia (Jerry) Huang ◽  
Robert Oberlies ◽  
Don Spencer ◽  
Jang Kim
Keyword(s):  
Impact Load ◽  
Research Work ◽  
Offshore Structures ◽  
Model Tests ◽  
Impact Loads ◽  
Dynamic Impact ◽  
Wave Impact ◽  
Impact Forces ◽  
Industry Practice ◽  
Drop Tests

For the design of offshore structures in harsh wave environments, it is essential to accurately determine the wave impact loads on the structure. To date, robust numerical prediction methods / algorithms for determining wave impact forces on offshore structures do not exist. Model testing continues to be the industry practice for determining wave impact forces on offshore structures. Accurate measurements of wave impact loads in model tests have been challenging for several decades. Transducers require the ability to capture the short duration, dynamic nature and high magnitude of impact loads. In order to qualify transducers for these types of measurements, we need to develop a way to physically impose dynamic impact loads on the transducers and to establish benchmark values that can be used to check the effectiveness of their measurements. In this paper, we present our recent research work on transducer qualification for wave impact load measurements, including their development, numerical analysis and wedge drop model tests. Our findings show that wedge drop tests can be used to impose dynamic impact loads for transducer qualification, and that the Wagner solution and / or validated computational fluid dynamics (CFD) simulations that include the effects of viscosity, compressibility and hydroelasticity can provide the appropriate benchmarking values. Numerical simulation results, model test measurements and findings on transducer qualification are presented and discussed in the paper.

A Paradigmatic and Methodological Review of Research in Outsourcing

2010 ◽  
pp. 19-28
Author(s):  
Vanita Yadav ◽  
Rajen Gupta
Keyword(s):  
Research Work ◽  
Past Research ◽  
Research Trends ◽  
Future Research ◽  
Business Process Outsourcing ◽  
Research Papers ◽  
Research Directions ◽  
Methodological Review ◽  
Research Activities ◽  
The Status

Due to the growing academic and practitioner interest in the field of outsourcing, there is a need to do a comprehensive assessment and synthesis of research activities to date. This chapter addresses this need and examines the academic literature on information systems outsourcing and business process outsourcing using a paradigmatic and methodological lens. The objective of this chapter is fourfold. Firstly, it examines the status of outsourcing research from 1995 to 2005 in eight leading academic journals, to compare the current research trends with past research directions in terms of methodologies applied. Secondly, it analyzes the research paradigms adopted in these research papers using the Operations Research Paradigm framework. Thirdly, it compares and contrasts the outsourcing research work published in three leading European journals with the work published in three leading American journals. Finally, it uncovers the implications of this study and the directions for future research.

A Paradigmatic and Methodological Review of Research in Outsourcing

2008 ◽  
pp. 71-88
Author(s):  
Vanita Yadav ◽  
Rajen K. Gupta
Keyword(s):  
Research Work ◽  
Past Research ◽  
Research Trends ◽  
Future Research ◽  
Business Process Outsourcing ◽  
Research Papers ◽  
Research Directions ◽  
Methodological Review ◽  
Research Activities ◽  
The Status

Due to the growing academic and practitioner interest in the field of outsourcing, there is a need to do a comprehensive assessment and synthesis of research activities to date. This chapter addresses this need and examines the academic literature on information systems outsourcing and business process outsourcing using a paradigmatic and methodological lens. The objective of this chapter is fourfold. Firstly, it examines the status of outsourcing research from 1995 to 2005 in eight leading academic journals, to compare the current research trends with past research directions in terms of methodologies applied. Secondly, it analyzes the research paradigms adopted in these research papers using the Operations Research Paradigm framework. Thirdly, it compares and contrasts the outsourcing research work published in three leading European journals with the work published in three leading American journals. Finally, it uncovers the implications of this study and the directions for future research.

scholarly journals Perspektiven für eine konzeptionelle Orientierung der Bildungsgeographie

2015 ◽  
Vol 70 (1) ◽  
pp. 75-88 ◽  
Author(s):  
T. Freytag ◽  
H. Jahnke
Keyword(s):  
Formal Education ◽  
Research Work ◽  
Human Geography ◽  
Reference Points ◽  
Future Research ◽  
International Studies ◽  
Geographical Education ◽  
Research Activities ◽  
Key Concepts ◽  
Suitable Reference

Abstract. Education has become central to the social and political debates in many countries. Under the influence of comparative international studies as well as national rankings of education institutions there is a growing awareness for social and regional inequalities of formal education infrastructure and processes. This article focuses on the geographical education research in Germany by reviewing existing research work on the one hand and opening perspectives for future studies in geography of education on the other. The main aim is to restructure the field of German Bildungsgeographie (geography of education) along key concepts and perspectives from human geography. After a brief introduction, the first part discusses the concept of Bildung (education) and its transformation. The following chapter sketches the major lines of research in geography of education in the German-speaking context. In the last and most extensive part six key concepts from human geography are pointed out as suitable reference points to situate existing and future research activities in the field of geography of education.

Potential Impact of Climate Change on Tanker Design

2011 ◽  
Author(s):  
Elzbieta M. Bitner-Gregersen ◽  
Torfinn Ho̸rte ◽  
Rolf Skjong
Keyword(s):  
Climate Change ◽  
Wave Climate ◽  
Offshore Structures ◽  
Extreme Weather ◽  
Structure Design ◽  
Extreme Weather Events ◽  
Future Research ◽  
Research Activities ◽  
Weather Events ◽  
The Impact

Global warming and extreme weather events reported in the last years have attracted a lot of attention in academia, industry and media. The ongoing debate around the observed climate change has focused on three important questions: will occurrence of extreme weather events increase in the future, which geographical locations will be most affected, and to what degree will climate change have impact on future ship traffic and design of ships and offshore structures? The present study shortly reviews the findings of the Intergovernmental Panel on Climate Change Fourth Assessment Report, AR4, [1] and other relevant publications regarding projections of meteorological and oceanographic conditions in the 21st century and beyond with design needs in focus. Emphasis is on wave climate and its potential implications on safe design and operations of ship structures. A risk based approach for marine structure design accounting for climate change is proposed. The impact of expected wave climate change on ship design is demonstrated for five oil tankers, ranging from Product tanker to VLCC. Consequences of climate change for the hull girder failure probability and hence the steel weight of the deck in the midship region is shown. Recommendations for future research activities allowing adaptation to climate change are given.

A Paradigmatic and Methodological Review of Research in Outsourcing

2011 ◽  
pp. 1-17
Author(s):  
Vanita Yadav ◽  
Rajen K. Gupta
Keyword(s):  
Research Work ◽  
Past Research ◽  
Research Trends ◽  
Future Research ◽  
Business Process Outsourcing ◽  
Research Papers ◽  
Research Directions ◽  
Methodological Review ◽  
Research Activities ◽  
The Status

Due to the growing academic and practitioner interest in the field of outsourcing, there is a need to do a comprehensive assessment and synthesis of research activities to date. This article addresses this need and examines the academic literature on information systems outsourcing and business process outsourcing using a paradigmatic and methodological lens. The objective of this article is fourfold. Firstly, it examines the status of outsourcing research from 1995 to 2005 in eight leading academic journals, to compare the current research trends with past research directions in terms of methodologies applied. Secondly, it analyzes the research paradigms adopted in these research papers using the Operations Research Paradigm framework. Thirdly, it compares and contrasts the outsourcing research work published in three leading European journals with the work published in three leading American journals. Finally, it uncovers the implications of this study and the directions for future research.

scholarly journals Non-Dimensional Groups, Film Thickness Equations and Correction Factors for Elastohydrodynamic Lubrication: A Review

Lubricants ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 95 ◽  
Author(s):  
Max Marian ◽  
Marcel Bartz ◽  
Sandro Wartzack ◽  
Andreas Rosenkranz
Keyword(s):  
Tribological Behavior ◽  
Numerical Models ◽  
Elastohydrodynamic Lubrication ◽  
Review Article ◽  
Future Research ◽  
Correction Factors ◽  
Roughness Effects ◽  
Lubricated Contacts ◽  
Research Activities ◽  
Line Point

Apart from complex numerical models to predict the tribological behavior of elastohydrodynamically lubricated contacts, non-dimensional similarity groups and analytically solvable proximity equations can be used to estimate integral fluid film parameters. Based upon the pioneering work presented by Dowson and Higginson as well as Blok and Moes, these approaches have been continuously improved over the years by modifications or correction factors to capture different contact geometries (line-, point- or elliptical contacts) as well as to include fluid compression, thermal, non-Newtonian, starvation or roughness effects. Consequently, this review article aims at systematically reviewing these modifications/corrections and discussing their applicability as well as limitations before presenting some recommendations for future research activities.

SME’s Performance Through Comparative Performance Indicators, Measured by Business Statistics- Albania Case

2017 ◽  
Vol 9 (1) ◽  
pp. 361
Author(s):  
Godiva Rembeci
Keyword(s):  
Economic Performance ◽  
National Economy ◽  
Performance Indicators ◽  
Future Research ◽  
Productivity Measurement ◽  
Comparative Performance ◽  
Global Consensus ◽  
Research Activities ◽  
Business Statistics ◽  
National Economies

Now days there is a global consensus among all stakeholders that SMEs represent a driving force to the overall economic development, due to their significant contribution both on GDP and employment of national economies. SMEs also by numbers dominate the world business stage, although their contribution does vary among the countries. SMEs in Albania represents about 98% of the total enterprises with a contribution to national GDP for about 70%. The structure and the performance of national economy is depended very much on the economic performance and contribution of SME, that’s why most of the governments have strategic programmes which support the SME’s development. To measure SMEs’ performance and their ability to compete on national and international markets requires a lot of information in all aspects. Through this paper the author aims to measure and analyze the economic performance of SMEs operating in Albania. To achieve this objective, official data on business statistics published by national the statistical office (INSTAT) are used for two years period 2014-2015. In addition using an international framework addressed to the objective “improve the techniques for SMEs productivity measurement”, for the first time, a set of comparative performance indicators is established and in doing so, those results can be used as term of reference in future research activities in SMEs sector. From the results it came out that although the positive growth rate of GDP during the last years , the performance indicators of SMEs show a slightly negative trend, indicating indirectly the need for support, in order to empower their contribution in national economy.

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