Nomadic input on mobile devices: the influence of touch input technique and walking speed on performance and offset modeling

In everyday life people use their mobile phones on-the-go with different walking speeds and with different touch input techniques. Unfortunately, much of the published research in mobile interaction does not quantify the influence of these variables. In this paper, we analyze the influence of walking speed, gait pattern and input techniques on commonly used performance parameters like error rate, accuracy and tapping speed, and we compare the results to the static condition. We examine the influence of these factors on the machine learned offset model used to correct user input and we make design recommendations. The results show that all performance parameters degraded when the subject started to move, for all input techniques. Index finger pointing techniques demonstrated overall better performance compared to thumb-pointing techniques. The influence of gait phase on tap event likelihood and accuracy was demonstrated for all input techniques and all walking speeds. Finally, it was shown that the offset model built on static data did not perform as well as models inferred from dynamic data, which indicates the speed-specific nature of the models. Also, models identified using specific input techniques did not perform well when tested in other conditions, demonstrating the limited validity of offset models to a particular input technique. The model was therefore calibrated using data recorded with the appropriate input technique, at 75% of preferred walking speed, which is the speed to which users spontaneously slow down when they use a mobile device and which presents a tradeoff between accuracy and usability. This led to an increase in accuracy compared to models built on static data. The error rate was reduced between 0.05% and 5.3% for landscape-based methods and between 5.3% and 11.9% for portrait-based methods

System for automatic detection and classification of cars in traffic

Objective: To develop a system for automatic detection and classification of cars in traffic in the form of a device for autonomic, real-time car detection, license plate recognition, and car color, model, and make identification from video. Methods: Cars were detected using the You Only Look Once (YOLO) v4 detector. The YOLO output was then used for classification in the next step. Colors were classified using the k-Nearest Neighbors (kNN) algorithm, whereas car models and makes were identified with a single-shot detector (SSD). Finally, license plates were detected using the OpenCV library and Tesseract-based optical character recognition. For the sake of simplicity and speed, the subsystems were run on an embedded Raspberry Pi computer. Results: A camera was mounted on the inside of the windshield to monitor cars in front of the camera. The system processed the camera’s video feed and provided information on the color, license plate, make, and model of the observed car. Knowing the license plate number provides access to details about the car owner, roadworthiness, car or license place reports missing, as well as whether the license plate matches the car. Car details were saved to file and displayed on the screen. The system was tested on real-time images and videos. The accuracies of car detection and car model classification (using 8 classes) in images were 88.5% and 78.5%, respectively. The accuracies of color detection and full license plate recognition were 71.5% and 51.5%, respectively. The system operated at 1 frame per second (1 fps). Conclusion: These results show that running standard machine learning algorithms on low-cost hardware may enable the automatic detection and classification of cars in traffic. However, there is significant room for improvement, primarily in license plate recognition. Accordingly, potential improvements in the future development of the system are proposed

Modelling and correcting for the impact of the gait cycle on touch screen typing accuracy

Walking and typing on a smartphone is an extremely common interaction. Previous research has shown that error rates are higher when walking than when stationary. In this paper we analyse the acceleration data logged in an experiment in which users typed whilst walking, and extract the gait phase angle. We find statistically significant relationships between tapping time, error rate and gait phase angle. We then use the gait phase as an additional input to an offset model, and show that this allows more accurate touch interaction for walking users than a model which considers only the recorded tap position

POTENCIJAL SPECIJALIZIRANIH PROIZVODA ZDRAVSTVENOG TURIZMA U SPLITSKO-DALMATINSKOJ ŽUPANIJI : Diplomski rad

U ovom radu analizira se aktualno stanje razvoja zdravstvenog turizma na nacionalnoj razini te na razini Splitsko-dalmatinske županije, razvojni potencijali te mogućnosti integracije postojeće turističke ponude u proizvode zdravstvenog odnosno medicinskog turizma. Temeljni cilj rada je identificirati ključne resurse i utvrditi potencijal Splitsko-dalmatinske županije za razvoj specijaliziranih proizvode zdravstvenog (primarno medicinskog) turizma. U teorijskom dijelu rada su izložene teorijske spoznaje iz stručne literature, znanstvenih članaka i internetskih izvora, a u empirijskom su dijelu predstavljeni zaključci iz dubinskih intervjua održanih sa sudionicima razvojnog procesa. U teorijskom dijelu rada su se za obradu podataka koristile metode dedukcije, indukcije, analize i sinteze. Empirijsko istraživanje uključivalo je niz intervjua s pitanjima podijeljenima u tri temeljne teme (aktualno stanje, razvojni potencijali i turistički aspekt zdravstvenog turizma), a podatci su se analizirali na način da su se tražila ponavljanja i preklapanja u stavovima sugovornika. Provedeno empirijsko istraživanje temeljni je doprinos rada jer se, prema saznanjima autora, po prvi put na ovoj razini prikupljaju stavovi osoba aktivno uključenih u razvojne procese o potencijalima područja Splitsko-dalmatinske županije. U radu su, na osnovu informacija iz empirijskog istraživanja te saznanja iz obrađenog teorijskog pregleda, dane preporuke za sustavno i sveobuhvatno iskorištavanje vrijednih resursa i prepoznatih razvojnih potencijala.This master's thesis analyses current state of affairs in health tourism on both national and regional (Split-Dalmatia county) level, development potentials and the possibilities of integrating existing tourism offer within health, and specifically medical tourism, products. The main goal is to identify key resources and determine the potential of developing specialized health and medical tourism products in Split-Dalmatia county. Key findings from scientific literature, papers and online sources were presented in theoretical part. Empirical research was based on a series of interviews with questions divided in three main topics (current situation, development potentials and tourism aspect of health tourism). Answers were analysed and compared to find matching statements and key points interviewees agree on. Primary contribution of the thesis is reflected in the empirical research which, to the author’s best knowledge, was the first research that explores opinions of the stakeholders actively involved in the development processes on the potentials of this type of tourism in Split-Dalmatia county. Based primarily on the findings of the empirical research but also on the information from the theoretical part, recommendations for systematic and comprehensive utilization of valuable resources and reaching identified development potentials are given

INVESTICIJE U TURIZMU REPUBLIKE HRVATSKE : Završni rad

Turističke aktivnosti i djelatnosti predstavljaju značajan segment u globalnom gospodarstvu. Rad se bavi analizom specifičnosti investiranja u turizam. Kvantificirati učinke turizma na gospodarstvo otežano je upravo zbog toga što je vrlo teško identificirati isključivo turističke djelatnosti. Iz istog razloga nije moguće precizno utvriditi volumen i efikasnost investicija. Rad teorijski definira pojmove investicija i investiranja s mikro i makro aspekta. Analiziraju se određene specifičnosti investiranja u turizam kao kapitalno i radno intenzivnu djelatnost. Iznose se spoznaje o stanju i problemima u ulaganju u razvojne potencijale u Hrvatskoj. U radu se predstavljaju i metode mjerenja efikasnosti investicija te se računa prosječna vrijednost ICOR pokazatelja za investicije u djelatnosti pružanja smještaja te pripreme i usluživanja hrane, budući da su za te djelatnosti dostupni relevantni statistički podatci. Rad sadrži prikaz trendova kretanja apsolutnog volumena investicija po odabranim kriterijima te udijela turističkih u ukupnim investicijama i BDP-u. Uz teorijski dio, u radu su predstavljeni najvažniji turistički investicijski projekti.Tourism acitivities represent a significant segment of world economy. This paper is a brief analysis of the specifics of tourism investments. It is difficult to quantify full effects of tourism on economy because of difficulties in separating purely tourism acitivities from the partially connected to tourism. Same difficulties are present in measuring volume and effectiveness of tourism investments. This paper defines terms of investing from the aspect of microeconomics and macroeconomics. Main focus is on analyzing tourism investing, it being both work and capital-intensive acitivity. Paper reveals the state of the art and problems related to investments in developement potentials in Croatia. It also explores main methods of measuring efficiency of investments, including the calculations of average ICOR value for tourism industry investments (activities related to accomodation providing and preparations and service of food, present in National Classification of Activities). Trends in absolute volume of investment along with data about share of tourism investments in total investments and in GDP are also presented. In addition to the theoretical part, paper also explores a selection of most relevant currently ongoing investment projects

POTENCIJAL SPECIJALIZIRANIH PROIZVODA ZDRAVSTVENOG TURIZMA U SPLITSKO-DALMATINSKOJ ŽUPANIJI : Diplomski rad

U ovom radu analizira se aktualno stanje razvoja zdravstvenog turizma na nacionalnoj razini te na razini Splitsko-dalmatinske županije, razvojni potencijali te mogućnosti integracije postojeće turističke ponude u proizvode zdravstvenog odnosno medicinskog turizma. Temeljni cilj rada je identificirati ključne resurse i utvrditi potencijal Splitsko-dalmatinske županije za razvoj specijaliziranih proizvode zdravstvenog (primarno medicinskog) turizma. U teorijskom dijelu rada su izložene teorijske spoznaje iz stručne literature, znanstvenih članaka i internetskih izvora, a u empirijskom su dijelu predstavljeni zaključci iz dubinskih intervjua održanih sa sudionicima razvojnog procesa. U teorijskom dijelu rada su se za obradu podataka koristile metode dedukcije, indukcije, analize i sinteze. Empirijsko istraživanje uključivalo je niz intervjua s pitanjima podijeljenima u tri temeljne teme (aktualno stanje, razvojni potencijali i turistički aspekt zdravstvenog turizma), a podatci su se analizirali na način da su se tražila ponavljanja i preklapanja u stavovima sugovornika. Provedeno empirijsko istraživanje temeljni je doprinos rada jer se, prema saznanjima autora, po prvi put na ovoj razini prikupljaju stavovi osoba aktivno uključenih u razvojne procese o potencijalima područja Splitsko-dalmatinske županije. U radu su, na osnovu informacija iz empirijskog istraživanja te saznanja iz obrađenog teorijskog pregleda, dane preporuke za sustavno i sveobuhvatno iskorištavanje vrijednih resursa i prepoznatih razvojnih potencijala.This master's thesis analyses current state of affairs in health tourism on both national and regional (Split-Dalmatia county) level, development potentials and the possibilities of integrating existing tourism offer within health, and specifically medical tourism, products. The main goal is to identify key resources and determine the potential of developing specialized health and medical tourism products in Split-Dalmatia county. Key findings from scientific literature, papers and online sources were presented in theoretical part. Empirical research was based on a series of interviews with questions divided in three main topics (current situation, development potentials and tourism aspect of health tourism). Answers were analysed and compared to find matching statements and key points interviewees agree on. Primary contribution of the thesis is reflected in the empirical research which, to the author’s best knowledge, was the first research that explores opinions of the stakeholders actively involved in the development processes on the potentials of this type of tourism in Split-Dalmatia county. Based primarily on the findings of the empirical research but also on the information from the theoretical part, recommendations for systematic and comprehensive utilization of valuable resources and reaching identified development potentials are given

INVESTICIJE U TURIZMU REPUBLIKE HRVATSKE : Završni rad

Turističke aktivnosti i djelatnosti predstavljaju značajan segment u globalnom gospodarstvu. Rad se bavi analizom specifičnosti investiranja u turizam. Kvantificirati učinke turizma na gospodarstvo otežano je upravo zbog toga što je vrlo teško identificirati isključivo turističke djelatnosti. Iz istog razloga nije moguće precizno utvriditi volumen i efikasnost investicija. Rad teorijski definira pojmove investicija i investiranja s mikro i makro aspekta. Analiziraju se određene specifičnosti investiranja u turizam kao kapitalno i radno intenzivnu djelatnost. Iznose se spoznaje o stanju i problemima u ulaganju u razvojne potencijale u Hrvatskoj. U radu se predstavljaju i metode mjerenja efikasnosti investicija te se računa prosječna vrijednost ICOR pokazatelja za investicije u djelatnosti pružanja smještaja te pripreme i usluživanja hrane, budući da su za te djelatnosti dostupni relevantni statistički podatci. Rad sadrži prikaz trendova kretanja apsolutnog volumena investicija po odabranim kriterijima te udijela turističkih u ukupnim investicijama i BDP-u. Uz teorijski dio, u radu su predstavljeni najvažniji turistički investicijski projekti.Tourism acitivities represent a significant segment of world economy. This paper is a brief analysis of the specifics of tourism investments. It is difficult to quantify full effects of tourism on economy because of difficulties in separating purely tourism acitivities from the partially connected to tourism. Same difficulties are present in measuring volume and effectiveness of tourism investments. This paper defines terms of investing from the aspect of microeconomics and macroeconomics. Main focus is on analyzing tourism investing, it being both work and capital-intensive acitivity. Paper reveals the state of the art and problems related to investments in developement potentials in Croatia. It also explores main methods of measuring efficiency of investments, including the calculations of average ICOR value for tourism industry investments (activities related to accomodation providing and preparations and service of food, present in National Classification of Activities). Trends in absolute volume of investment along with data about share of tourism investments in total investments and in GDP are also presented. In addition to the theoretical part, paper also explores a selection of most relevant currently ongoing investment projects

Ultra Wideband Assisted Localization of Semi-Autonomous Floor Scrubber

The paper describes the design and features of the novel semi-autonomous floor scrubber add-on module, used for cleaning large indoor spaces. Module is designed in such a manner that it can be easily attached and detached from scrubber machine and that additional sensors can be introduced if needed. The paper focuses on the localization capabilities of the machine in several sensor setups with emphasis on the use of ultra wideband (UWB) real-time localization system (RTLS). It also proposes fusion of sensor data from several sources including novel use of wheel encoder’s data in UWB setup. Analysis is performed in terms of localization accuracy and reliability as well as associated advantages and disadvantages. Obtained results demonstrated that inclusion of UWB subsystem, despite its price and accuracy (20 cm in ideal, line of sight, conditions), based on behavior switching yields more reliable and accurate results in open spaces (up to 25 times in position and 2 times in orientation) and that its accuracy can be further improved with inclusion of wheel encoder data

Real-Time Body Orientation Estimation Based on Two-Layer Stochastic Filter Architecture

Članak obrađuje postupke estimacije prostorne orijentacije krutog tijela u realnom vremenu temeljene na mjerenjima inercijskih i magnetskih senzora. Pregledom standardnih pristupa estimaciji orijentacije, kao moguća alternativa predložena je nova arhitektura stohastičkog estimacijskog filtra temeljena na kombiniranju Kalmanovog i čestičnog algoritma u dvije razine. Arhitektura dvorazinske prirode je uporabljena jer omogućava veću primjenjivost nadogradnjom već implementiranih Kalmanovih ili čestičnih filtra. U radu su projektirane četiri dvorazinske arhitekture koje su različitim kombinacijama ostvarivale interakciju među razinama. Pri tome je kao ogledni primjer uporabljena estimacija orijentacije glave čovjeka. Izvedena su ispitivanja točnosti i računske efikasnosti kako na simuliranim tako i na stvarnim mjernim podacima u off-line režimu rada, te je odabrana ona arhitektura s najboljim rezultatima. Odabrana arhitektura je zatim implementirana u realnom vremenu pri međudjelovanju čovjeka s računalom, te je ispitana na nekoliko praktičnih primjena. Na temelju ostvarenih rezultata su izvedeni zaključci te predložena moguća poboljšanja, te daljnji pravci istraživanja.The article presents real time rigid body orientation estimation using inertial and magnetic sensors. Based on the review of orientation estimation literature we suggest, as possible alternative to standard approaches, novel two-layer stochastic estimation filter architecture based on Kalman and particle filters combined into two layers. Two-layer architecture was chosen because it enables greater applicability via upgrade of already implemented Kalman or particle filters. Four two-layer filter architectures were designed, each one enabling different layer interaction. Estimation of human head orientation was chosen as a case example. Simulated data and batch head orientation measurement data were used to test the proposed architectures in terms of accuracy and computational efficiency and to select the best one in terms of aforementioned performance parameters. Selected architecture was then implemented in real time for human-computer interaction and was tested on several practical applications. Obtained results are presented and discussed and future research directions suggested