This wide-ranging study explored various parameters of visual search in relation to computer screen displays. Its ultimate goal was to help identify factors which could result in improvements in commercially available displays within the 'real world’. Those improvements are generally reflected in suggestions for enhancing efficiency of locatabolity of information through an acknowledgement of the visual and cognitive factors involved. The thesis commenced by introducing an ergonomics approach to the presentation of information on VDUs. Memory load and attention were discussed. In the second chapter, literature on general and theoretical aspects of visual search (with particular regard for VDUs) was reviewed. As an experimental starting point, three studies were conducted involving locating a target within arrays of varying configurations. A model concerning visual lobes was proposed. Two text-editing studies were then detailed showing superior user performances where conspicuity and the potential for peripheral vision are enhanced. Relevant eye movement data was combined with a keystroke analysis derived from an automated protocol analyser. Results of a further search task showed icons to be more quickly located within an array than textual material. Precise scan paths were then recorded and analyses suggested greater systematicity of search strategies for complex items. This led on to a relatively 'pure' search study involving materials of varying spatial frequencies. Results were discussed in terms of verbal material generally being of higher spatial frequencies and how the ease of resolution and greater cues available in peripheral vision can result in items being accessed more directly. In the final (relatively applied) study, differences in eye movement indices were found across various fonts used. One main conclusion was that eye movement monitoring was a valuable technique within the visual search/VDU research area in illuminating precise details of performance which otherwise, at best, could only be inferred.

Bakgrund Muskuloskeletala besvär i nacke och skuldra är vanligt förekommande arbetsrelaterade sjukdomar bland bildskärmsarbetare. Detta orsakar individuellt lidande med stora kostnader för samhället i storleksordningen 0.5% till 2% av ett lands BNP, men även för företag som utöver ökade omkostnader även riskerar sämre produktion och kvalitet. Det finns en oro att bildskärmsarbetande med progressiva glasögon arbetar med en ökad huvudextension och huvudprotraktion sk ”gamnacke”. Få jämförande studier har dock gjorts på HE respektive FHP vid användandet av progressiva glasögon, och ännu färre med subjekten i deras naturliga arbetsmiljö. Syfte – I denna studie undersöktes om det, i subjektens egen arbetsmiljö, föreligger ett samband mellan begreppet gamnacke och bildskärmsarbete vid användandet av progressiva glasögon avseende faktorerna FHP och HE jämfört med bildskärmsarbete utan progressiva glasögon. Subjekt –Datainsamlingen har skett på sju stycken olika företag i storstockholmsområdet under tidsperioden Mars-April 2017. Testgruppen bestod av 3 män och 7 kvinnor med en medelålder på 57,80 år (±8,18). Tid som de använt progressiva glasögon var 5,85 år (±5,59). kontrollgruppen bestod av 4 män och 6 kvinnor med en medelålder på 55,90 år (±3,60). Metod – Subjekten fotograferades med en smartphonekamera i ett stativ med horisontellt vattenpass, sittande vid sina skrivbord framför sina egna bildskärmar. Tre fotografier togs under 5 minuters tid på respektive subjekt. Subjekten var inte varse om exakt vid vilken tidpunkt fotografierna togs. En mobilapplikation användes för att ta ut vinklar för HE och FHP. Medelvärdena användes sedan för vidare analys med ett two-independent-sample test. Resultat – Testgruppens medelvärde för huvudets protraktion, TFHP var 42,20° (±7,15°). Testgruppens vinkel för mätning av huvudets extension, THE, hade medelvärdet 17,73° (±5,55°). Kontrollgruppens medelvärde för huvudets protraktion, KFHP var 40,87° (±7,53°). Kontrollgruppens medelvärde av huvudets extension, KHE var 11,53° (±7,42°). Korrelationen mellan progressiva glasögon och FHP var inte statistisk signifikant (p = 0,739), detta gällde även för korrelationen mellan progressiva glasögon och HE (p = 0,063). Konklusion – Resultatet av studien visade inget statistiskt signifikant samband gällande att bildskärmsarbetande i subjektetens naturliga arbetsmiljö med fullprogressiva glasögon hade en högre grad FHP eller HE än bildskärmsarbetande utan fullprogressiva glasögon i förhållande till lodlinjen respektive horisontallinjen, däremot sågs en tendens till en högre grad av HE hos gruppen med fullprogressiva glasögon i förhållande till horisontallinjen (p=0,063). / Introduction – Musculoskeletal disorders of the neck and shoulders are common occupational diseases among VDU operators. This causes individual suffering with high costs for society at around 0.5% to 2% of a countries GDP, as well as for companies, that besides high costs also risk a poorer production and quality. There is a concern that VDU operators with progressive lenses have an increased head extension and Forward head posture. However, Few comparative studies have been made on head extension and Forward head posture on subjects with progressive lenses and even fewer with subjects in their natural working environment. Aim – In this study, the aim was to, in the subjects own natural working environment, investigate whether there is a connection between the concept of poor posture in regards of FHP and HE, and VDU operators in the use of progressive lenses, compared to VDU operators without progressive lenses. Materials – The data was collected from seven different companies in the Greater Stockholm area during the period March-April 2017. The test group consisted of 3 men and 7 women with an average age of 57.80 years (± 8.18). The time spent using progressive lenses was 5.85 years (± 5.59). The control group consisted of 4 men and 6 women with an average age of 55.90 years (± 3.60). Method - The subjects were photographed with a smartphone on a leveled tripod, sitting at their own desks in front of their own monitors. Three photos were taken within 5 minutes on each subject. The subjects did not know exactly when the photographs were taken. A mobile application was used to extract angles for HE and FHP measurements. The mean values were then used for further analysis with a two-independent sample test. Results – The test group's mean head protrusion, TFHP was 42.20° (±7.15°). The test group's angle for measuring the head extension, THE, had an average of 17.73° (±5.55°). The control group's mean head protrusion, KFHP was 40.87° (±7.53°). The control group's mean of the head extension, KHE was 11.53° (±7.42°). The correlation between progressive lenses and FHP was not significant (p = 0.739), nor was the correlation between progressive lenses and HE significant (p = 0.063). Conclusion – The results of the study showed no statistically significant correlation that VDU operators in the subject's natural working environment with progressive lenses have a higher degree of FHP or HE than VDU operators without progressive lenses in relation to the vertical- and horizontal line respectively. On the other hand, they had a trend towards a higher HE than VDU operators without progressive lenses with a p-value of 0.063.

Darbo tikslas. Įvertinti profilaktinių ergonomikos principų taikymo darbo vietoje mokymo poreikį ir galimybes „X“ įmonėje. Uždaviniai. Įvertinti darbuotojų informatyvumą apie ergonomines darbo padėtis, darbo ir poilsio režimą, specialius akių ir fizinius pratimus ir jų atlikimą per pertraukas „X“ įmonėje. Nustatyti profilaktinių ergonomikos principų taikymo darbo vietoje mokymo darbuotojams poreikį ir galimybes „X“ įmonėje. Tyrimo metodika. Tyrimas buvo atliktas 2012 m. gruodžio – 2013 m. sausio mėn. „X“ įmonėje, kurioje darbuotojai dirba kompiuteriu visą darbo dieną. Anoniminės anketos būdu buvo apklausti 123 darbuotojai. Duomenų analizei buvo apskaičiuotas Chi kvadrato kriterijus, taip pat, z kriterijus. Reikšmingumo lygmuo, kai p<0,05. Rezultatai. 12,2 proc. darbuotojų, kurie sieja savo sveikatos nusiskundimus su ergonomine darbo padėtimi, ir 38,8 proc. respondentų, kurie nesieja, sėdi tiesiai naudojantis kompiuteriu (p<0,05). Apie 5 – 10 min. pertraukas yra neinformuota 96,3 proc. nedalyvavusių panašiuose ergonomikos mokymuose, 94,6 proc. respondentų, kurie sieja sveikatos nusiskundimus su ergonomine darbo padėtimi bei 100 proc., kurių darbo stažas 10 – 20 m. Informuoti apie fizinius ir specialius akių pratimus buvo 1,9 proc. darbuotojų, kurie nedalyvavo panašiuose ergonomikos mokymuose, 5,4 proc. siejantys sveikatos nusiskundimus su ergonomine darbo padėtimi, labiausiai informuoti buvo dirbantys iki 10 m. tokio pobūdžio darbą (4,8 proc.). 73,1 proc. nedalyvavusių... [toliau žr. visą tekstą] / Aim of the study. To evaluate training need and possibilities in application of the preventive ergonomic principles at the workplace of the „X” company. Objectives. To evaluate employees‘ knowledge about an ergonomic work posture, work and rest regimens, the special physical and eye exercises and their performance during breaks at the „X“ company. To determinate training need and possibilities in application of the preventive ergonomic principles at the workplace of the „X“ company. Methods. The research was carried out during December 2012 - January 2013 period in the „X“ company, where employees work with computers all working day. An anonymous questionnaire was filled out by 123 employees. The Chi-square and z criteria were calculated for data analysis, and the level of significance was when p<0.05. Results. The rate of the employees, sitting straight in front of a computer, was 12.2% of those, who relate their health complaints with the ergonomic work posture, and 38.8% of the respondents, who do not relate (p<0.05). 96.3% of the employees, who have not participated in similar ergonomic trainings before, 94.6% of the respondents, who relate their health complaints with the ergonomic work posture, and 100%, whose length of employment is from 10 to 20 years, do not know about 5 – 10 min. breaks. About the special physical and eye exercises were informed 1.9% of the employees, who have not participated in similar ergonomic trainings before, 5.4% of the respondents, who... [to full text]

The concept of "visual fatigue" has been studied for 70 years or more. In that time, no single metric of measuring visual fatigue nor one agreed-upon set of tasks to induce visual fatigue has been settled upon. Not even a robust definition of visual fatigue has been established. This research worked to solve some of those problems. This research first set out to develop an index of visual fatigue that could be used effectively in quantifying the subjective experience of visual fatigue. Then it sought to create a set of measurable tasks, representative of office work, that would induce visual fatigue. Taking these two developments, an experiment using human participants was conducted to validate these developments and work toward solving two issues in the visual fatigue field: how visual display technology and ambient illumination affect the onset of visual fatigue. A 4x4 within-subjects design was developed and executed to study how these two independent variables affected ratings of visual fatigue, performance on the task battery, subjective image quality judgments, and contrast sensitivity shifts. Two cathode ray tube (CRT) and two active-matrix LCD (AMLCD) monitors were used in this study. While many instances of the monitors as a whole caused significant differences in reports of visual fatigue, performance, subjective image quality, and contrast sensitivity loss, only a slight effect of display technology was found. Four of eleven visual fatigue and two of eight subjective image quality dimensions showed that the LCD monitors induced more visual fatigue and were rated poorer than the CRT monitors. Ambient illumination levels of 0, 300, 600, and 1200 lux affected all four groups of dependent variables. On the whole, lighting caused visual fatigue, with "watery eyes" and "glare from lights" being adversely affected by brighter lighting. The 0 and 1200 lux were associated with the worst performance, while 300 lux was associated with the best performance. Subjective image quality was affected by lighting, with increasing lighting causing bothersome screen reflections and more temporal (e.g., flicker and jitter) distortions; 600 lux induced more reports of image sizing anomalies. Finally, it caused significantly worse shifts at the 6.0 c/deg spatial frequency on the contrast sensitivity test. The data show that lighting of 300 lux is the best of these four illumination levels. The results of this study not only contribute to the body of research in the areas of display technology and ambient illumination, but several developments of this research are offered to the research community: a complete survey metric of visual fatigue, a standardized battery of tasks for studying visual fatigue and image quality, and a comprehensive subjective image quality survey. / Ph. D.

Magistro darbo objektas – Lietuvos universitetų leidyklų veikla. Darbo tikslas – atsižvelgiant į Lietuvoje po 1990 m. įvykusius pokyčius ekonomikoje bei švietimo sistemoje, išanalizuoti Lietuvos universitetų leidybinės veiklos evoliuciją, įvertinant kiekvienos aukštosios mokyklos leidyklos veiklą ir leidybinį repertuarą. Leidyklų veikla tiriama 1991-2003 m. laikotarpiu, nes 1990 m. žymių pokyčių universitetų leidyboje neįvyksta bei nėra statistinių duomenų. Pagrindiniai darbo uždaviniai: aptarti universitetinės leidybos raidą pasaulyje ir pagrindinius jos veiklos principus; išanalizuoti Lietuvos universitetų leidyklų statistinius duomenis, nustatyti lyderius ir jų veiklos specifiką; išanalizuoti universitetų leidinius, jų repertuarą. Prieita prie išvados, kad steigiant universitetus, taip pat buvo kuriami leidybos skyriai, kurių pagrindinė paskirtis – leisti bei platinti mokslo ir mokomąja literatūrą akademinei bendruomenei. Leidyklos yra nepelno siekiančios organizacijos, gaunančios finansavimą iš įvairių Respublikos ministerijų, komisijų ir kitų rėmėjų bei universitetų biudžetų, kuriems yra pavaldžios. Kiekviena universiteto leidykla savo leidybinėje veikloje orientuojasi į aukštojoje mokykloje dėstomų studijų programų aprūpinimo literatūra bei akademinės bendruomenės informavimo ir jos narių darbų publikavimo poreikius. Dauguma universitetų leidyklų įsteigė mažas spaustuves ir įsigijo įrangą, kuri paspartino ir atpigino knygų leidybą, tačiau dalį spaudos darbų užsako... [toliau žr. visą tekstą] / The subject of work – activities of the publishing offices of Lithuania – The main purpose – to examine Lithuanian publishing offices evolution evaluating each high schools practice and publications repertoire considering the changes appeared in economy and educating system in Lithuania after 1990. Publishing offices activities are studied during period of 1991 – 2003, because there wasn’t any essential shift in university publishing and there is no statistical information presented about 1990. The main purpose shall be obtained by accomplishing these tasks: to dispute about university’s publishing processes and the main principles of it’s activities in the world; to analyze statistical information of publishing offices of the Lithuanian universities, to estimate leaders and the main principles of their activities; to analyze the publications and repertoire of universities. To conclude, every established university had it’s own publishing department, which was to publish and distribute scientific and educational literature to academic society. Publishing offices are non-profit organizations, which are financed by various Republic ministries, committees and other supporters also university budgets to which they are subordinated. Most of universities publishing houses established small printing houses and obtained equipment, which made printing quicker and cheaper. All Lithuanian universities concern about distribution, but this sphere is too complicated to many of them. The... [to full text]