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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Spatial and temporal variations of the surface energy balance and ablation on the Belcher Glacier, Devon Island, Nunavut, Canada.

Duncan, Angus Unknown Date
No description available.
142

Balance mechanisms during standing and walking in young and older adults

Lee, Sungeun Unknown Date
No description available.
143

The Effects of Organisational Work-Life Balance Initiatives on Accountants in New Zealand

Branch, Sarah Helen January 2008 (has links)
Employee perception of the provision of work-life balance initiatives within their firms and their usage/intended usage of these initiatives was obtained for 77 New Zealand accountants employed in four accounting firms. Statistical analysis indicated the impact of these employee perceptions on overall job satisfaction, organisational commitment, job stress, intentions to quit, family-work conflict and work-family conflict. Employees' perception of the provision of work-life balance initiatives failed to significantly impact the employee measures. Utilising or intending to utilise work-life balance initiatives significantly impacted employee measures of organisational commitment and job stress. These mixed results suggest that simply installing work-life balance initiatives in accounting firms is not enough. Obtaining measures of within firm social support for employees utilising work-life balance initiatives needs further investigation. It is suggested that instead of adopting a 'one size fits all' approach, that organisations need to install initiatives specifically suited to the individual demographics of their workforce.
144

Do diurnal dissolved oxygen cycles have diagnostic value for assessing pollution status in lakes?

Ansa-Asare, Osmund Duodu January 1998 (has links)
The effects of pollutant burdens on natural cyclic patterns in aquatic ecosystems have been studied, to test the hypothesis that a parameter or parameters describing the <I>pattern of variation </I>in a single determinant, such as DO or pH, may be used to describe the status of a body of water more meaningfully than results from single spot measurements. In this study the background water quality in a Scottish and a Ghanaian lake was assessed, then <I>rafts </I>were built on the lakes (Myrtle Dam and Weija Lake respectively) creating three small lakes to test the effects of pollutant loads (<I>e.g. </I>organics and nutrients) on them. Laboratory investigations to study the behaviour of the pollutants on DO or pH cycles were carried out, and then a dynamic DO model was developed to describe the cyclic behaviour of DO. Finally, the model was used to investigate the effects of added pollutant burdens on the DO cycles. Water quality assessment of Myrtle Dam and Weija Lake by using the <I>Weighted Water Quality Index </I>proved that Weija Lake has doubtful quality with WQI 51, which needs improvement. Myrtle Dam WQI of 73 shows that the lake waters are unpolluted (or recovered from pollution). It is also well oxygenated at the surface and receives no toxic discharge. The <I>raft</I> experiments for Myrtle Dam and the Weija Lake have been used to demonstrate that, in the raft tubes, organic loadings do have effects on the oxygen cycles, and showed that there are two effects. One is that, with a small organic loading, the mean DO value dropped, then increased as the organic loading was consumed. The second is that the amplitude of the DO cycle increased as the organic loading increased from 2.5 to 5.0 mg L<sup>-1</sup> TOC for Myrtle Dam, and decreased for Weija Lake as the organic loading increased from 2.5 to 5.0 mg L<sup>-1</sup> TOC. The laboratory experiments in both Ghana and Aberdeen proved to be useful in explaining the effects of nutrients and trace elements on the DO cycles. It was evident that the higher the algal concentration, the greater was the DO cycle and 30% v/v (<I>c.a. </I>254 mg L<sup>-1</sup> chlorophyll 'a' content ≍ 17 g L<sup>-1</sup> biomass aqueous algal suspension) proved to be the most suitable concentration for investigations, because, with higher organic loadings, the 100% aqueous algal suspension proved to be too concentrated and caused total deoxygenation.
145

The effect of aging on movement characteristics and postural control during stooping and crouching tasks

Glinka, Michal January 2013 (has links)
Stooping and crouching (SC) postures are integral to many daily tasks, such as retrieving objects from the floor and reaching to low shelves, yet nearly one in four community-dwelling older adults (24%) report having difficulty or being completely unable to perform SC movements. While limited research has identified physical (e.g., lower extremity strength and joint immobility) and behavioural (e.g., obesity and balance confidence) determinants of SC difficulty, little is known about how aging affects the manner in which SC tasks are performed. The objective of this thesis was to describe age-related differences in movement kinematics and balance control during stooping and crouching tasks. Healthy younger (n = 12) and older (n = 12) participants performed a series of object-retrieval tasks ??? varying in initial lift height, precision required, and duration ??? that required them to bend over or reach toward the floor. In addition to kinematic and postural control measures describing the movements, measures of lower limb isometric strength, passive range of motion (ROM), and balance confidence were obtained for each participant. Compared to younger, older participants moved slower into and out of self-selected postures, which were characterized by higher whole-body centre of mass (COM) vertical positions. Specifically, older adults exhibited lower vertical COM linear velocities and lower hip, knee, and ankle joint angular velocities during transitions, and higher COM heights achieved through comparatively less flexion in the hip, knee, and ankle joints during object retrieval. Older participants also displayed smaller, more centralized anterior-posterior (AP) COM excursions and lower COM velocities, but higher centre of pressure (COP) activity compared to younger participants, demonstrated through increased COP velocity (relative to COM velocity) and more frequent COP adjustments aimed at regulating COM position. Changing task constraints (i.e., lower initial lift height or longer duration) elicited greater postural changes in younger compared to older participants, potentially reflecting a diminished ability in older adults to make appropriate task-specific adaptations. In particular, younger participants were 4 times more likely than older participants to use a lower to the floor, forefoot crouching posture, especially during longer duration tasks. Older participants also had decreased leg strength and less passive range of motion compared to younger participants. Overall, the results of this thesis demonstrate that despite moving slower through shorter distances, older adults displayed higher COP activity, which may have reflected a heightened effort to control COM position, during SC tasks. This compliments existing works describing age-related differences in movement strategies and balance control during lifting and sit-to-stand tasks. Further work exploring relationships between specific physiological and behavioural factors and SC task performance measures is needed to inform therapeutic intervention strategies.
146

A Biomechanical Study of Angular Momentum and External Moments During a Ballet Turn

Walters-Stewart, Coren 10 March 2011 (has links)
The following thesis applies equations of motion used in linear locomotion (gait analysis) to the analysis of the purely rotational motion of the fouetté or tour à la seconde. Modifications to the method of analysis include the creation of several MATLAB programs to compute improved estimates of the moment of inertia tensor, three-dimensional angular momentum about the dancer’s centre of mass. The results of this investigation—the quantification of angular momentum and external moments—are compared to similar results from gait analysis to demonstrate how the dancer maintains balance during rotational motion. The variables calculated by the MATLAB programs are particularly relevant in the field of balance control research in the context of inputs into the body’s balance control systems.
147

Accounting for intangible assets in the food, drink and media industries in the UK

Ong, Audra Wei Ming January 2000 (has links)
No description available.
148

Energy Audit of HiG Examination Building

Yao, Li, Liao, Xinyan January 2014 (has links)
Nowadays, energy is becoming more and more important. With the development of society, the demand of energy is also increasing correspondingly. There is 22% of the total energy which is used in building part. A more effective and sustainable energy system becomes necessary due to increasing energy prices and demand. The aim of this thesis is to make an energy survey of this building, evaluating different sources of energy supply and losses in this building. By evaluating, a better thermal comfort is expectedly achieved when having examinations, and a possible saving method is also expected in order to reduce the cost of this system.  In this project, the building is located in University of Gävle which is surveyed. It has 2 floors. The first floor is underground as a basement. An examination room is included in the second floor. There are a space heating system and heating recovery system ventilation in this examination building. At first step of analysis, the data of construction, ventilation, district heating and hot tap water were arranged by Mr. Magnus. Secondly, an energy balance had been done, and it helped to make energy input and output more clearly. In energy supply part, the solar radiation is 22.4MWh, the internal heat from people is 1.95MWh, the internal heat from equipment is 5.63MWh and district heating is 184MWh. In energy losses part, the transmission loss is 165MWh, the mechanical ventilation loss is 38.3MWh, the infiltration loss is 8.38MWh and the hot tap water is 2.09MWh. Thirdly, results of calculations were analyzed. At last, the optimization methods were given to save energy. The optimization methods were changing type of windows and improving indoor temperature which influenced the transmission loss part. Another method was reducing operating time of the ventilation system. Through these optimizing methods, the total energy use is reduced from 214MWh to 179MWh, and district heating is reduced from 184MWh to 149MWh. District heating of this building is supplied by Gävle Energi company, which is able to save 20% cost by these optimizing methods. According to the investment analysis, 19thousand SEK energy is saved per annum.
149

Spatial and temporal variations of the surface energy balance and ablation on the Belcher Glacier, Devon Island, Nunavut, Canada.

Duncan, Angus 06 1900 (has links)
In the summer of 2008 (June 2nd September 19th) detailed measurements of meteorological conditions and glacier surface properties were conducted in the Belcher Glacier catchment (718 km2), Devon Island Ice Cap, Nunavut, Canada. These measurements were used to force and validate a distributed surface energy balance and sub-surface snow model capable of calculating surface ablation rates and meltwater runoff. This study represents a contribution to the International Polar Year (IPY) Glaciodyn project, whose overall aim is to examine the role of hydrology and ice dynamics in the response of marine-terminating glaciers in the Arctic to climate change. Spatially-averaged total water equivalent (w.e.) ablation was 677 mm w.e., and total predicted runoff during the 2008 summer was 3.9 x 108 m3. Net radiation (87%) was the main source of energy over the study period, followed by the sensible heat flux (13%). Net longwave radiation and the latent heat flux represented an overall energy loss from the surface. Modelled melt season duration lasted from June 17th August 15th, and the majority of ablation occurred in two main periods, from June 26th July 18th, and from July 27th to August 14th. Snowfall and lower air temperatures limited ablation between these dates and after August 15th. Ice exposure at elevations below 1000 m occurred by July 1st. Periods of high ablation rates were associated with positive air temperatures and high net shortwave radiation receipts, and with near surface air temperature gradients that were shallow or inverted (i.e. higher air temperatures at higher elevations). Periods of minimum ablation rates occurred when net shortwave radiation receipts were reduced (e.g. following summer snowfall) and when air temperatures were negative. The largest changes in both the net surface energy balance and ablation rates were linked to changes in surface albedo associated with (i) snowpack removal and ice exposure, and (ii) summer snowfall events. Modelled time series of runoff from individual sub-catchments within the Belcher catchment will be used to force a coupled hydrology and ice flow dynamics model of the Belcher Glacier that will be used to investigate the dynamic response of tidewater-terminating glaciers to surface hydrological forcing.
150

Balance mechanisms during standing and walking in young and older adults

Lee, Sungeun 06 1900 (has links)
Maintaining balance is controlled by two different processes: feedforward and feedback control. Feed-forward control is used prior to performing voluntary movements whereas feedback control is used to correct for unexpected perturbations. Studies suggested that age-related changes in postural responses may contribute to increased risk of falls in older adults. To address whether Tai Chi training can induce improved patterns of feed-forward control, voluntary arm elevations during standing were performed. Compared to age-matched controls, smaller displacements of the center of pressure were found among older adults who practice Tai Chi. This may suggest adapted feed-forward control induced by training. To investigate feedback control, perturbations were applied while walking with various arm constraints. Context-dependent modulation in response amplitude was found with changing levels of postural threat in older adults, comparable to young adults. Delayed onset latencies and frequent inhibition of Soleus may suggest less effective balance strategies employed in older adults, and an increased risk of falling. / Rehabilitation Science

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