1,721,396 research outputs found
Attention to Effects of Different Cross-Cultural Levels in User Research Method’s Interface: Discipline or Nationality – Which Has Stronger Force?
No full textIn the recent years, design research have developed a long way in investigating about the users and their contexts. It was aimed to challenge the way ‘cross-culture influence’ has been considered in design research field: should there be better way than profiling users solely based on nationality in multinational research project for product specification. Major findings through this research included (1) Nationality factor influenced remarkably on user performance but not much on user attitude. In contrast, discipline factor influenced significantly on every elements of user participation. (2) The gaps of user attitude and performance with nationality as the function maintained same levels while the effects from discipline factor intensified upon the increase of task complexity and change of ask characteristic. Overall, Discipline factor dominated Nationality factor, insisting on the importance of considering different levels of participants’ cultures in designing the interface of user experience research methods
Morphodynamics of seasonally closed coastal inlets at the central coast of Vietnam
No full textSituated in a monsoon-prone humid tropical region, Vietnam is affected by both oceanic and continental climates causing disasters to the country like riverine flooding and storm induced damage. The coastal districts of Vietnam have a population of about 18 million habitants, account for nearly one fourth of the total population of the country and locate about 50% of the major towns and cities of Vietnam. Most of the people currently living in the coastal zone have their livelihood mainly relying on marine resources and they are also the most vulnerable to sea-related natural disasters, such as storms and floods. The natural disasters occurring in the coastal strip in the central part of Vietnam, caused by meteorological and oceanographical factors, are intensified by human interventions, like the damming of rivers for various purposes or the extensive deforestation for the creation of agricultural lands. With more than 1,000 km of coastline, the central coast of Vietnam has more than sixty inlets and river mouths discharging into the South China Sea. These systems play a vital role in social-economic activities in the region. The steep rivers with abundant natural but temporally unevenly distributed flows make the low-lying coastal plains in the region prone to inundation by flooding, while the river is almost dry during the rest of the year. Specific topographical features and hydrological characteristics of the region produce a particularly high seasonal geomorphological variation of tidal inlets and river mouths, from narrowing, shoaling or entirely closing in the dry season to widening or breaching in the flood period. Frequent disasters set back development efforts in this poorest region of Vietnam and trap people in a cycle of poverty. Stabilising inlets at the central coast of Vietnam therefore is recognised as one of the priority tasks to mitigate potential risks caused by natural disasters, especially by floods and storms on low-lying coastal plains, and to promote a safe and stable condition for social-economic development in the region. To carry out this task, Vietnam needs both substantial financial and human resources, particularly knowledge and experience in coastal engineering, which is not trivial for a developing country. Additionally, strong seasonal variation of inlets and estuaries contribute to the complexity of problems and raise a necessity to implement a strategy for inlet and river mouth stabilisation under the constraints of a shortage of resources and knowledge. This thesis focuses on tidal inlets and estuaries in a wave-dominated, micro-tidal environment under the influence of episodic river flooding in the central coast of Vietnam. Natural behaviour and morphological stability of tidal inlets, which significantly interact with channel migration, entrance shoaling or closure have been identified and analysed based on field observations, historical satellite images, topographical maps and bathymetrical data. Based on the regional natural settings and hydrodynamic-morphological features, tidal inlets along the central coast of Vietnam can be divided into two main categories, namely, (1) barrier lagoon inlets and (2) wave dominated estuary inlets. A conceptual model for channel evolution and seasonal opening/closure of tidal inlets is proposed which describes the cyclic evolution of a typical tidal inlet at the central coast of Vietnam. In the conceptual model, the inlet entrance is forced both by the alongshore current which deposits sediment in the inlet channel and by the ebb tidal and river generated currents which erode sediment from the inlet channel. The interpretation of the Escoffier diagram is extended conceptually to explain the seasonal variation of both open equilibrium and closure. The variation is regulated by the seasonal variation of river flow and littoral drift. The conceptual model indicates the two major processes which dominate in the dry and the flood season leading to a deviation from the stable and unstable equilibrium points in the Escoffier diagram. This supports our understanding of seasonal variation of coastal inlets and estuaries in a region that experiences monsoons and storms causing a large fluctuation in littoral drift and ebb flow at the central coast of Vietnam. To get deeper insight into the underlying processes and cross-sectional stability of an schematised tidal inlet, regulated by tides only and regulated by both tides and waves, the process-based morphodynamic modelling system Delft-3D has been applied. In the model the tidal period, amplitude, basin area and initial inlet dimensions were changed systematically to create different hydrodynamic environments for inlet evolution. The model successfully reproduces the evolution of the channel flow area towards equilibrium for a tidal inlet and is able to describe the main behaviour of an inlet in response to a range of tide and wave conditions and geometries. The model results are in good agreement with empirical relationships (O'Brien, 1969; Jarrett, 1976) and the analytical solution (DiLorenzo, 1988) of Escoffier's diagram. To investigate location stability of inlet channels, seven experiments were designed to cover 3 different stability ranges (poor, fair to good stability). Reliable model results increase the understanding of the processes underlying the migration and closure of a tidal inlet. It is found that tidal inlet behaviour and location stability is linked to the number of channels on the ebb delta, the curvature if there is only one channel, type of bar on the ebb delta, the migration of the updrift barrier island, the distance between the inlet throat and the outer of margin of entrance bar. The model results demonstrate that the process-based model is able to reproduce the morphological evolution of a tidal inlet fairly consistent with the Bruun et al. (1978) empirical criteria for location stability. A typical example of a tidal inlet migrating due to oblique waves which includes features such as ebb channel migration, shifting and diminishing, and the bypassing of ebb shoals from the updrift to the downdrift barriers is investigated and discussed in detail. In another case inlet closure due to prolongation of the ebb channel and infilling with littoral-drift material in the foreshore is also observed. Furthermore, the model results indicate that Escoffier's closure curve is solely applicable to the stability of the channel gorge and thus insufficient to explain the closure of a tidal inlet due to littoral sand infilling into the main ebb channel. In this study solutions are developed for the stabilisation of tidal inlets at the central coast of Vietnam. The solutions are based on the natural behaviour and evolution of two different types of tidal inlets in the region, namely 1) barrier lagoon inlets and 2) inlets formed at the mouth of wave dominated estuaries. For each type of inlet, both short-term and long-term solutions as well as structural and non-structural solutions are taken into account. The solution for the stabilisation of inlets at the central coast of Vietnam is to restrict and/or response to problems. To verify proposed solutions for the stabilisation of inlets along the central coast of Vietnam, process-based modelling is employed to simulate the evolution of a schematised tidal inlet that is stabilised by two jetties and by using river flow to flush the inlet channel. The simulation results show that the inlet after stabilisation by jetties remains open but the inlet channel is highly variable due to the accumulation and erosion of sediment in between two jetties. A sedimentation and erosion pattern is found which is related to the distance in between the two jetties and the strength of the tidal power. An optimum distance between the two jetties that takes into account the effectiveness of the jetties and the structural safety during a major flood event need further study. For inlets that are stabilised by using river flow to flush the inlet, a set of simulation scenarios in which different flushing discharges and flushing durations was designed. For a limited number of simulation scenarios, the model results show that with the same amount of flushing volume, the scenario that has a longer flushing duration and a sufficient flushing discharge is more efficient than the scenario that uses a high flushing discharge over a short duration. This means that the flushing efficiency is closely related to the flushing duration rather than the flushing discharge. Moreover, the flushing moment (at the beginning of the ebb phase or at the beginning of the flood phase) will also contribute to the efficiency of the solution but needs more study.Department of Hydraulic EngineeringCivil Engineering and Geoscience
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
A first calibration of the one-dimensional model of the Nhat Le River basin
No full textThis thesis provides a first draft of a one-dimensional model of the Nhat Le River Basin. The model is almost ready for use due to the short period of time. The model requires at least an adequate calibration before using. With this thesis a first start has been made. Eventually, with the model, the probability of water levels in the Nhat Le River (Quang Binh Province, Vietnam) can be estimated, which are needed for calculation of the embankments height along the Nhat Le River. In the beginning of the project this thesis had another research question. But at the start of the assignment the provided documents did not suffice due to missing and/or wrong drawings, wrong calculations and lack on key input. Some information should be bought and the newly presented documents never came or came too late. Although it didn’t work out as planned, a lot about the Vietnamese culture and organizational structure has been learned. The new research question was originated around the calculations of the newly proposed embankments along the Nhat Le River. The provided documents calculated the levels of the embankments with the old regulations. These calculations were based on the old Vietnamese regulations, which are not sufficient anymore. The new regulations require a one-dimensional model to estimate the highest water level in the river with different frequency floods. Due to the short period of time, the model is not yet ready for implementation. However some recommendations for optimization and further use of the model are given. The one-dimensional model is made with the computer software HEC-RAS. The Water Resources University Hanoi provided the required data, including boundary conditions and cross-sections. Data in Vietnam is not easy to obtain. It took a long time to get the proper information and support from different parties. Although, this assignment is a good first start of modelling the one-dimensional model. In order to establish the final one-dimensional model the following steps should be conducted: - More cross-sections along the Dia Giang and Kien Giang river branches in order to determine the correct slopes of the river branches; - Development of the Dia Giang and Kien Giang river branches with wider cross-sections, including floodplains and storage areas; - Calibration of the Dia Giang river branch; - Calibration of the whole Nhat Le river Branch; - Implementation of the My Trung sluice in the Kien Giang river branch; - Data of different frequency floods in the Dia Giang and Kien Giang river branch to estimate the different high water levels in the main of Nhat Le river in different scenarios; - Clearness about the positions of the newly constructed embankments.Hydraulic EngineeringHydraulic EngineeringCivil Engineering and Geoscience
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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