LED lighting design strategies to enhance window appearance and increase energy savings in daylit office spaces

Vertical windows are the most common and simplest method to introduce daylight to interior spaces of office buildings, while also providing a view and connection to the outside. However, high contrast ratios between windows and surrounding surfaces can cause visual discomfort for occupants and can negatively influence their health and productivity. Consequently, building occupants may try to adapt their working environment through closing blinds and turning on lights in order to improve indoor visual comfort. Such interventions defeat the purpose of daylight harvesting systems and can increase the forecast electric lighting consumption in buildings that include such systems. A simple strategy to prevent these problematic consequences is to reduce the luminance contrasts presented by the window wall by increasing the luminance of areas surrounding the window through the sparing use of energy-efficient supplementary lighting, such light emitting diodes (LEDs). This paper presents the result of a pilot study in typical office in Brisbane, Australia that tests the effectiveness of a supplementary LED lighting system. The study shows an improvement in the appraisal of the visual environment is achieved using the supplementary system, along with up to 88% reductions in luminance contrast at the window wall. Also observed is a 36% reduction in the likelihood of user interventions that would increase energy usage. These results are used as the basis of an annual energy simulation of the test office and indicate that supplementary systems could be used to save energy beyond what is typically realised in side lit office spaces.

Tiedettä Pohjantähden alla : Pohjoisen tutkimus ja Ruotsin tiedeseurojen suhteet Ranskaan 1700-luvulla

In the eighteenth century, the birth of scientific societies in Europe created a new framework for scientific cooperation. Through a new contextualist study of the contacts between the first scientific societies in Sweden and the most important science academy in Europe at the time, l Académie des Sciences in Paris, this dissertation aims to shed light on the role taken by the Swedish learned men in the new networks. It seeks to show that the academy model was related to a new idea of specialisation in science. In the course of the eighteenth century, it is argued, the study of the northern phenomena and regions offered the Swedes an important field of speciality with regard to their foreign colleagues. Although historical studies have often underlined the economic, practical undertone of eighteenth-century Swedish science, participation in fashionable scientific pursuits had also become an important scene for representation. However, the views prevailing in Europe tied civilisation and learning closely to the sunnier, southern climates, which had lead to the difficulty of portraying Sweden as a learned country. The image of the scientific North, as well as the Swedish strategies to polish the image of the North as a place for science, are analysed as seen from France. While sixteenth-century historians had preferred to put down the effects of the cold and claim a similarity of northern conditions to the others, the scientific exchange between Swedish and French researchers shows a new tendency to underline the difference of the North and its harsh climate. An explanation is sought by analysing how information about northern phenomena was used in France. In the European academies, new empirical methods had lead to a need for direct observations on different phenomena and circumstances. Rather than curiosities or objects for exoticism, the eighteenth-century depictions of the northern periphery tell about an emerging interest in the most extreme, and often most telling, examples of the workings of the invariable laws of nature. Whereas the idea of accumulating knowledge through cooperation was most manifest in joint astronomical projects, the idea of gathering and comparing data from differing places of observation appears also in other fields, from experimental philosophy to natural studies or medicine. The effects of these developments are studied and explained in connection to the Montesquieuan climate theories and the emerging pre-romantic ideas of man and society.

Skogsbränslets elementära sammansättning med tanke på förbränningsprocessen och för näringsämnesförluster i ekosystemet

There are several reasons for increasing the usage of forest biomass for energy in Finland. Apart from the fact that forest biomass is a CO2 -neutral energy source, it is also a domestic resource distributed throughout the country. Usage of forest biomass in the form of logging residues decreases Finland’s dependence of energy import and increases both incomes and employment. Wood chips are mainly made from logging residues, which constitute 64 % of the raw material. A large-scale use of forest biomass requires heed also to the potential negative aspects. Forest bioenergy is used extensively, but its impacts on the forests soil nutrition and carbon balance has not been studied much. Nor have there been many studies on the heavy metal or chlorine content of logging residues. The goal of this study was to examine the content of carbon, macronutrients, heavy metals and other for the combustion harmful substances in Scots pine and Norway spruce wood chips, and to estimate the effect of harvesting of logging residues on the forests carbon and nutrient balance. Another goal was to examine the energy content of the clear cut remains. The Wood chips for this study were gathered from pine and spruce dominated clear cut sites in southern Finland, in the costal forests between Hankoo and Siuntio. The number of sample locations were 29, and the average area was 3,15 ha and the average timber volume 212,6 m3 ha -1. The average logged timber volume was for Scots pine timber 70 m3 ha -1 and for Norway spruce timber 124 m3 ha -1 and for deciduous timber (birch and alder) 18,5 m3 ha -1. The proportion of spruce in the logging residues and the stand-volume were relevant for how much nutrients were taken from the forest ecosystem when harvesting logging residues. In this study it was noted that the nutrient content of the logging residues clearly increased when the percentage of spruce in the timber volume increased. The S, K, Na and Cl -contents in the logging residues in this study increased with an increasing percentage of spruce, which is probably due to the fact that the spruce is an effective collector of atmospheric dry-deposition. The amounts of nutrients that were lost when harvesting logging residues were less than those referred to in the literature. Within a circulation period (100 years), the forest soil gets substantially more nutrients from atmospheric deposition, litter fall and weathering than is lost through harvesting of logging residues after a clear cut. Harvesting of the logging residues makes for a relatively modest increase of the quantity of carbon that is removed from the forest compared to traditional forestry. Due to the fact that the clear cut remains in my study showed a high content of chlorine, there is a risk of corrosion in connection to the incineration of the logging residues in power plants especially at coastal areas/forests. The risk of sulphur -related corrosion is probably rather small, because S concentrations are relatively low in woodchips. The clear cut remains showed rather high heavy metal contents. If the heavy metal contents in this study are representative for the clear cut remains in the coastal forests generally, there might be reason to exert some caution when using the ash for forest fertilizing purposes.

Evolution of the tilapia fishery with specific reference to the Nile tilapia (Oreochromis niloticus Linne)

As a fishery, the immensely large (c. 68,800 km2 ) Lake Victoria is a unique ecosystem which together with a riverine connection to the Lake Kyoga basin share a common endemic "Victorian" fish fauna (Greenwood 1966). Until the 1950s, the single socio economically most important species of fish in these two lakes was the native Oreochromis esculentus Graham (Graham 1929) even though the lake also contained a second native tilapiine, 0reochromis variabilis , and over 300 other fish species (Beauchamp, 1956).

Piecewise Linear Models for the Quasiperiodic Transition to Chaos

We formulate and study analytically and computationally two families of piecewise linear degree one circle maps. These families offer the rare advantage of being non-trivial but essentially solvable models for the phenomenon of mode-locking and the quasi-periodic transition to chaos. For instance, for these families, we obtain complete solutions to several questions still largely unanswered for families of smooth circle maps. Our main results describe (1) the sets of maps in these families having some prescribed rotation interval; (2) the boundaries between zero and positive topological entropy and between zero length and non-zero length rotation interval; and (3) the structure and bifurcations of the attractors in one of these families. We discuss the interpretation of these maps as low-order spline approximations to the classic ``sine-circle'' map and examine more generally the implications of our results for the case of smooth circle maps. We also mention a possible connection to recent experiments on models of a driven Josephson junction.

A Bayesian Approach for TCP to Distinguish Congestion from Wireless Losses

(This Technical Report revises TR-BUCS-2003-011) The Transmission Control Protocol (TCP) has been the protocol of choice for many Internet applications requiring reliable connections. The design of TCP has been challenged by the extension of connections over wireless links. In this paper, we investigate a Bayesian approach to infer at the source host the reason of a packet loss, whether congestion or wireless transmission error. Our approach is "mostly" end-to-end since it requires only one long-term average quantity (namely, long-term average packet loss probability over the wireless segment) that may be best obtained with help from the network (e.g. wireless access agent).Specifically, we use Maximum Likelihood Ratio tests to evaluate TCP as a classifier of the type of packet loss. We study the effectiveness of short-term classification of packet errors (congestion vs. wireless), given stationary prior error probabilities and distributions of packet delays conditioned on the type of packet loss (measured over a larger time scale). Using our Bayesian-based approach and extensive simulations, we demonstrate that congestion-induced losses and losses due to wireless transmission errors produce sufficiently different statistics upon which an efficient online error classifier can be built. We introduce a simple queueing model to underline the conditional delay distributions arising from different kinds of packet losses over a heterogeneous wired/wireless path. We show how Hidden Markov Models (HMMs) can be used by a TCP connection to infer efficiently conditional delay distributions. We demonstrate how estimation accuracy is influenced by different proportions of congestion versus wireless losses and penalties on incorrect classification.

An Independent-Connection Model for Traffic Matrices

A common assumption made in traffic matrix (TM) modeling and estimation is independence of a packet's network ingress and egress. We argue that in real IP networks, this assumption should not and does not hold. The fact that most traffic consists of two-way exchanges of packets means that traffic streams flowing in opposite directions at any point in the network are not independent. In this paper we propose a model for traffic matrices based on independence of connections rather than packets. We argue that the independent connection (IC) model is more intuitive, and has a more direct connection to underlying network phenomena than the gravity model. To validate the IC model, we show that it fits real data better than the gravity model and that it works well as a prior in the TM estimation problem. We study the model's parameters empirically and identify useful stability properties. This justifies the use of the simpler versions of the model for TM applications. To illustrate the utility of the model we focus on two such applications: synthetic TM generation and TM estimation. To the best of our knowledge this is the first traffic matrix model that incorporates properties of bidirectional traffic.

THE PIANO FANTASY FROM BACH TO DANIELPOUR

The Fantasy, as the term suggests, is a genre that composers have found congenial for exploring innovative and imaginative processes. Works in this genre are numerous in the solo piano literature, and extend even to works for piano and orchestra and to chamber music with piano. I was curious to explore how a specific genre of music maintained similar characteristics but evolved over time. A fantasy is primed to be inventive and I wanted to see how composers from different eras and backgrounds would handle their material in this genre. I have learned that composers worked through formal developments while making innovations within this genre. The heart of my dissertation is presented through the recording project. Because ofthe abundance ofpiano fantasies, many works had to be excluded from this project for time's sake. On two compact discs, I have recorded approximately two hours of solo piano music. I have included some shorter fantasies to magnify significant developments from era to era, country to country, and composer to composer. The first disc has recordings of eighteenth and nineteenth-century fantasies: Chromatic Fantasy and Fugue, BWV 903 by J.S. Bach (1685-1750); Fantasia inC major, H. XVII, 4 by Franz Joseph Haydn (1732-1809); Fantasy inc minor, K. 475 by Wolfgang Amadeus Mozart (1756- 1791); Fantasia inf-sharp minor, Op. 28 by Felix Mendelssohn (1809-1847); and Polonaise-Fantaisie in A-flat major, Op. 61 by Frederic Chopin (1810-1849). On the second disc I have included mid-19th, 20th and 2151-century piano fantasies: Fantasy and Fugue on the Theme B-A-C-H by Franz Liszt (1811-1886); Fantasia Baetica by Manuel de Falla (1876-1946); Three Fantasies by William Bergsma (1921-1994); Fantasy, Aria and Fugue by Frederic Goossen (1927-2011); and Piano Fantasy ("Wenn ich einmal sol! scheiden") by Richard Danielpour (b. 1956). The accompanying document includes program notes for each of the pieces recorded. They were recorded on a Steinway "D" in Dekelboum Concert Hall at the University of Maryland by Antonino D'Urzo ofOpusrite Productions. This document is available in the Digital Repository at the University of Maryland and the CO's are available through the Library System at the University of Maryland.

Self-esteem mediates the relationship between connectedness to nature and body appreciation in women, but not men

Connectedness to nature (i.e., an affective and experiential connection to nature) is known to have a positive effect on psychological well-being, but its specific associations with body image have not been fully examined. To attend to this oversight, we conducted a preliminary investigation of associations between connectedness to nature and body appreciation. A total of 380 British adults completed measures of connectedness to nature, body appreciation, and self-esteem. Bivariate correlations revealed significant positive associations between all variables in women. In men, body appreciation was significantly correlated with self-esteem, but not connectedness to nature. Mediation analysis showed that, in women, self-esteem fully mediated the relationship between connectedness to nature and body appreciation. In men, body appreciation was significantly associated with self-esteem, but not connectedness to nature. These results point to a potential route for improving body image among women through connectedness to nature and self-esteem, but further research is necessary.

Design of Resistivity Instrumentation for a He3 Cryostat and its Application to the Charge Density Wave Superconductor CuxTiSe2

Fermi patches in quasi-two dimensional charge density waves (CDW) have not described the connection to superconductivity (SC) according to theory adequately at this point in time. The connection between CDW and SC in the quasi-two dimensional material CuxTiSe2 is an interesting one which might reveal mechanisms in unconventional superconductors. A previous Brock graduate student grew crystals of CuxTiSe2. The precise doping of the samples was not known. In order to determine the doping parameter x in CuxTiSe2, a sensitive resistivity measurement system was necessary. A new resistivity measurement system was designed and implemented utilizing an Infrared Labs HDL-10 He3 cryostat. By comparing with data from the literature, doping of two samples was investigated using the new measurement system and a Quantum Design Magnetic Property Measurement System (MPMS). Methods for determining the doping revealed that the old resistivity system would not be able to determine the CDW transition temperature of highly doped samples or doping for elongated samples due to electronic noise. Doping in one sample was found to be between x=0.06 and x=0.065. Values of doping in the second sample had a discrepancy but could be explained by incorrect sample orientation.

Reconciliation as a Political Concept: Some Observations and Remarks

This paper summarizes a number of observations and reflections on the phenomenon and practice called “reconciliation”, in connection to peace processes and peace-building initiatives. In particular it draws from processes followed by the author, in East Timor in particular, but also in Europe, the Middle East and, more recently, Colombia. It is a discussion paper. The purpose is to invite to reflection, both on the level of perspectives as well as concepts. It is developed from a lecture called “The Challenge of Reconciliation” held at Universidad Nacional, Bogotá, in December 2003. Following substantial revision since then (making the text more than double in length) I realize that today not many parts of the original text are still recognizable from that presentation, then organized by the Embassy of Sweden in Colombia, as part of its commitment to the peace process in that country. I have accepted the invitation of the Center of Political and International Studies (Centro de Estudios Políticos e Internacionales, CEPI), at Universidad del Rosario, to publish this work in progress, to reach a broader public in Colombia and contribute to the discussion on econciliation. The field of “political reconciliation” is evolving, definitions of reconciliation are abounding, and different contributors have different takes on the subject matter, quite naturally. It is the author’s view, that reconciliation can and should not be “held captive” of any particular field of study. It relates to fundamental, some would call it existential, issues of meaning, trust, contradictions, and suffering in the midst of a violent, political reality. It is wise to tread softly on ground with such a complex bottom.

High-latitude particle precipitation and its relationship to magnetospheric source regions

Two central issues in magnetospheric research are understanding the mapping of the low-altitude ionosphere to the distant regions of the magnetsphere, and understanding the relationship between the small-scale features detected in the various regions of the ionosphere and the global properties of the magnetosphere. The high-latitude ionosphere, through its magnetic connection to the outer magnetosphere, provides an important view of magnetospheric boundaries and the physical processes occurring there. All physical manifestations of this magnetic connectivity (waves, particle precipitation, etc.), however, have non-zero propagation times during which they are convected by the large-scale magnetospheric electric field, with phenomena undergoing different convection distances depending on their propagation times. Identification of the ionospheric signatures of magnetospheric regions and phenomena, therefore, can be difficult. Considerable progress has recently been made in identifying these convection signatures in data from low- and high-altitude satellites. This work has allowed us to learn much about issues such as: the rates of magnetic reconnection, both at the dayside magnetopause and in the magnetotail; particle transport across the open magnetopause; and particle acceleration at the magnetopause and the magnetotail current sheets.

Within - versus between - country differences in risk attitudes: implications for cultural comparisons

Cultural comparisons enjoy increasing popularity in economics. Since cultural comparison must abandon random allocation to treatments, it is unclear whether differences found between countries can be attributed to country characteristics or are merely driven by differences in subject pools. In experiments in two Chinese cities and at two campuses in Ethiopia, we show that within-country differences are negligible. Differences between the two countries, on the other hand, are large.

Tillhörighetens gränser : Internationell adoption och ursprungets betydelse i svensk utredningsretorik

Boundaries of belonging: transnational adoption and the significance of origin in Swedish official rhetoric This article explores how the category of ‘transnational adoptees’ in Sweden is constructed in two Official Government Reports (SOU). The article is inspired by poststructuralist perspectives on welfare and social categorization, and draws from a postcolonial and feminist theoretical framework. ‘Transnational adoptees’ as a category is understood as constituted through discourse, and given meaning in different contexts. In the reports, a fundamental importance is attached to the fact that individuals with a background as transnationally adopted have been separated from their birth family and country of birth. It is argued that mental problems and a split identity are consequences to be expected from the separation. (Re)connection to the origin is therefore considered to be crucial for the well-being of the group. The article concludes that this line of reasoning is based on a specific logic of blood and roots, in which ‘transnational adoptees’ are understood as belonging to their countries of birth, rather than Sweden. The logic of blood and roots can be read as a form of racialized othering, but also as a discursive exclusion of ‘transnational adoptees’ from Sweden as an imagined, national community.

Influences of infrastructure and attitudes to health on value of travel time savings in bicycle journeys

In this paper we investigate how attitudes to health and exercise in connection with cycling influence the estimation of values of travel time savings in different kinds of bicycle environments (mixed traffic, bicycle lane in the road way, bicycle path next to the road, and bicycle path not in connection with the road). The results, based on two Swedish stated choice studies, suggest that the values of travel time savings are lower when cycling in better conditions. Surprisingly, the respondents do not consider cycling on a path next to the road worse than cycling on a path not in connection to the road, indicating that they do not take traffic noise and air pollution into account in their decision to cycle. No difference can be found between cycling on a road way (mixed traffic) and cycling in a bicycle lane in the road way. The results also indicate that respondents that include health aspects in their choice to cycle have lower value of travel time savings for cycling than respondents that state that health aspects are of less importance, at least when cycling on a bicycle path. The appraisals of travel time savings regarding cycling also differ a lot depending on the respondents’ alternative travel mode. The individuals who stated that they will take the car if they do not cycle have a much higher valuation of travel time savings than the persons stating public transport as the main alternative to cycling.