Individual differences in human-computer interaction

This thesis initially presents an 'assay' of the literature pertaining to individual differences in human-computer interaction. A series of experiments is then reported, designed to investigate the association between a variety of individual characteristics and various computer task and interface factors. Predictor variables included age, computer expertise, and psychometric tests of spatial visualisation, spatial memory, logical reasoning, associative memory, and verbal ability. These were studied in relation to a variety of computer-based tacks, including: (1) word processing and its component elements; (ii) the location of target words within passages of text; (iii) the navigation of networks and menus; (iv) command generation using menus and command line interfaces; (v) the search and selection of icons and text labels; (vi) information retrieval. A measure of self-report workload was also included in several of these experiments. The main experimental findings included: (i) an interaction between spatial ability and the manipulation of semantic but not spatial interface content; (ii) verbal ability being only predictive of certain task components of word processing; (iii) age differences in word processing and information retrieval speed but not accuracy; (iv) evidence of compensatory strategies being employed by older subjects; (v) evidence of performance strategy differences which disadvantaged high spatial subjects in conditions of low spatial information content; (vi) interactive effects of associative memory, expertise and command strategy; (vii) an association between logical reasoning and word processing but not information retrieval; (viii) an interaction between expertise and cognitive demand; and (ix) a stronger association between cognitive ability and novice performance than expert performance

Boskoop heeft meerwaarde voor sierteelt

De regio Boskoop is een (inter)nationaal centrum voor de boomteelt. Voor de streekplanherziening Zuid-Holland Oost is in opdracht van deprovincie Zuid-Holland studie gedaan naar de autonome ontwikkeling van het boomteeltcomplex Boskoop en de interacties met het bloembollencomplex 'De Bollenstreek'

Fluidic Technology and Some Recent Applications to Space and Oceanography

This paper is presented to show the degree of advancements that fluidic technology is making in various technical disciplines. Examples are used and discussed based on the many programs sponsored by the government. The references used here represent only a small percent of the total. Individuals with specific interests or applications can expand the reference list on the choosen subject to take advantage of the considerable amount of advanced research and development already completed

Edge smoothing for real-time simulation of a polygon face object system as viewed by a moving observer

The visual system within an aircraft flight simulation system receives flight data and terrain data which is formated into a buffer memory. The image data is forwarded to an image processor which translates the image data into face vertex vectors Vf, defining the position relationship between the vertices of each terrain object and the aircraft. The image processor then rotates, clips, and projects the image data into two-dimensional display vectors (Vd). A display generator receives the Vd faces, and other image data to provide analog inputs to CRT devices which provide the window displays for the simulated aircraft. The video signal to the CRT devices passes through an edge smoothing device which prolongs the rise time (and fall time) of the video data inversely as the slope of the edge being smoothed. An operational amplifier within the edge smoothing device has a plurality of independently selectable feedback capacitors each having a different value. The values of the capacitors form a series which doubles as a power of two. Each feedback capacitor has a fast switch responsive to the corresponding bit of a digital binary control word for selecting (1) or not selecting (0) that capacitor. The control word is determined by the slope of each edge. The resulting actual feedback capacitance for each edge is the sum of all the selected capacitors and is directly proportional to the value of the binary control word. The output rise time (or fall time) is a function of the feedback capacitance, and is controlled by the slope through the binary control word

De Onze-Lieve-Vrouwekathedraal van Doornik : onafhankelijkheidsmonument voor een bisdom

  The Our Lady Cathedral in Tournai is today one of the most remarkable churches of the Low Countries. In the Middle Ages, it was the mother church of the most northern bishopric of France. The early 12 Century Cathedral was built during a highly turbulent chapter in the history of the bishopric. After five centuries in personal union with the diocese of Noyon, and a long struggle for independence, Tournai recovered its own bishop in 1146. The architecture of the new early 12 Century Cathedral was to represent the venerable age of the Church of Tournai and its original independence. The triconchos (trefoil) ground plan points to the martyrium churches: it recalls the ideal of the early Church and its local saintly founder. The impressive group of five towers refers to the future, being a prefiguration of the Holy City Jerusalem that will descent on earth at the end of time. The strength of the Cathedral as a representation of the episcopal see of an independent bishopric of Tournai was visualised in the attribute of Eleutherius, the new patron saint: a model of the group of five towers forms a concise summary of the architecture of the Cathedral.  Medieval and Early Modern Studie

Multifactorial Examination of Sex-differences in Head Injuries and Concussions Among Collegiate Soccer Players: NCAA ISS, 2004-2009.

BACKGROUND: While head injuries and concussions are major concerns among soccer players, the multifactorial nature of head injury observations in this group remains relatively undefined. We aim to extend previous analyses and examine sex-differences in the incidence of head injuries, odds of head injuries within an injured sample, and severity of head injuries, among collegiate soccer players between 2004 and 2009. METHODS: Data collected within the National Collegiate Athletic Association (NCAA) Injury Surveillance System (ISS) between the years of 2004 and 2009, were analyzed in this study. Unadjusted rate ratios (RR), compared incidence rates between categories of sex, injury mechanism, setting and competition level. We also examined sex-differences in head injury incidence rates, across categories of the other covariates. Multivariable logistic regression and negative binomial regression modeling tested the relation between sex and head injury corollaries, while controlling for contact, setting, and competition level. RESULTS: Between 2004 and 2009, head injuries accounted for approximately 11% of all soccer-related injuries reported within the NCAA-ISS. The rate of head injuries among women was higher than among men (RR = 1.23, 95% CI = [1.08, 1.41]). The rate of head injuries due to player-to-player contact was comparable between women and men (RR = 0.95, 95% CI = [0.81, 1.11]). Whereas, the rate of injury due to contact with apparatus (ball/goal) was nearly 2.5 times higher (RR = 2.46, 95% CI = [1.76, 3.44]) and the rate due to contact with a playing surface was over two times higher (RR = 2.29, 95% CI = [1.34, 3.91]) in women than in men. In our multifactorial models, we also observed that the association between sex and head injury corollaries varied by injury mechanism. CONCLUSIONS: Sex-differences in the incidence, odds (given an injury), and severity (concussion diagnosis, time-loss) of head injuries varied by injury mechanism (player-to-player contact vs. all other mechanisms) in this sample

Bomen over ruimte: een studie naar de toekomstige ruimtebehoefte voor de boomteelt in de regio Boskoop

In het kader van de streekplanherziening Zuid-Holland Oost is een schatting gemaakt van de toekomstige ruimtebehoefte voor de boomteelt in de regio Boskoop tot 2015. Op basis van toekomstige ontwikkelingen in de vraag naar boomteeltproducten, de (inter)nationale concurrentiepositie van de boomteelt in de regio Boskoop en de bedrijfsstructuur is de extra ruimtebehoefte geschat op 2% per jaar. Het totale areaal boomteelt in 2015 komt hiermee op 1.435 ha (+ 335 ha), waarvan de helft pot- en containerteelt en de helft in de vollegrond. Ook zal tot 2015 de teelt onder glas gestaag toenemen. Om het boomteeltcentrum in de regio Boskoop in stand te houden is niet alleen behoefte aan extra ruimte, maar zal ook voldaan moeten worden aan een aantal kwalitatieve randvoorwaarden. De belangrijkste randvoorwaarden zijn: planologische zekerheid, ruimte voor ondersteunend glas, goede bedrijfsstructuur, goede infrastructuur, kwalitatief goed opgeleid personeel en professioneel ondernemersscha

Effects of Polychlorinated Biphenyl Compounds and Proposed PCB-Replacement Products on Embryo-Larval Stages of Fish and Amphibians

Static renewal bioassays were performed with four polychlorinated biphenyls, including Capacitor 21 and Aroclors 1016, 1242, and 1254. Each compound was used to treat embryo-larval stages of the rainbow trout (Salmo gairdneri), channel catfish (Ictalurus punctatus), goldfish (Carassius auratus), redear sunfish (Lepomis microlophus), leopard frog (Rana pipiens), Fowler\u27s toad (Bufo fowleri), and American toad (Bufo americanus). Developmental stages of the trout were the most sensitive, with LC50 \u27s at 4 days posthatching of 0.3, 1.0, 1.1, and 1.6 μg/l for Aroclors 1254, 1242, 1016, and Capacitor 21, respectively. LC1\u27s ranged between 0.009-0.011 μg/l. Fowler\u27s toad was the most tolerant species, and LC50 \u27s varied from 3.7-28.0 μg/l. Toxicity of the PCB\u27s generally increased with percent chlorine substitution. Bioassays also were conducted with dioctylphthalate (D0P), diisononylphthalate, and Dow Corning 561 silicone, three products proposed as replacements for PCB\u27s. Embryos and larvae of the channel catfish, redear sunfish, leopard frog, and Fowler\u27s toad were exposed through 4 days posthatching. Catfish was the most sensitive species, and sunfish was the most resistant. Based on LC50 values, replacement products were found to be 2-5 orders of magnitude less toxic than PCB\u27s. Continuous flow embryo-larval bioassays were performed on Capacitor 21 and DOP. Test species included redear sunfish, rainbow trout, and largemouth bass (Micropterus salmoides). Paralleling results from static renewal tests, flow-through data reflected a vast difference in toxicity between PCB\u27s and potential replacements, and good data correlation was achieved between the two bioassay procedures

Sensitivity of Vertebrate Embryos to Heavy Metals as a Criterion of Water Quality: Phase III: Use of Fish and Amphibian Eggs as Bioindicator Organisms for Evaluating Water Quality

Fish and amphibian eggs, embryos and early posthatched (larval) stages were evaluated as bioindicator organisms with which to monitor the quality of natural water resources. Eggs of 9 species were cultured in water collected from each of 11 Inner Bluegrass rivers and streams. The latter were chosen to represent water sources varying in quality from extremely poor to good. Selection was based on the sources and magnitude of pollution, and the diversity and density of piscine populations. Cultures were maintained in vitro, using 12-hour changes of water. Averaging data for all 9 animal species, egg hatchability (embryonic survival) ranged from 0% for the most contaminated water to 94% for uncontaminated water found to support a healthy aquatic biota. Eggs of the squirrel treefrog and gray treefrog were the most sensitive of 5 amphibian species tested, and of 4 fish species, rainbow trout eggs proved most susceptible to water contaminants