Uses and Challenges of Collecting LiDAR Data from a Growing Autonomous Vehicle Fleet: Implications for Infrastructure Planning and Inspection Practices

Autonomous vehicles (AVs) that utilize LiDAR (Light Detection and Ranging) and other sensing technologies are becoming an inevitable part of transportation industry. Concurrently, transportation agencies are increasingly challenged with the management and tracking of large-scale highway asset inventory. LiDAR has become popular among transportation agencies for highway asset management given its advantage over traditional surveying methods. The affordability of LiDAR technology is increasing day by day. Given this, there will be substantial challenges and opportunities for the utilization of big data resulting from the growth of AVs with LiDAR. A proper understanding of the data size generated from this technology will help agencies in making decisions regarding storage, management, and transmission of the data. The original raw data generated from the sensor shrinks a lot after filtering and processing following the Cache county Road Manual and storing into ASPRS recommended (.las) file format. In this pilot study, it is found that while considering the road centerline as the vehicle trajectory larger portion of the data fall into the right of way section compared to the actual vehicle trajectory in Cache County, UT. And there is a positive relation between the data size and vehicle speed in terms of the travel lanes section given the nature of the selected highway environment

A survey on daylighting potentiality in the offices of Dhaka Bangladesh

In the offices of Dhaka, artificial light is the main contributor to the visual environment, even though there is an abundance of daylight and the working hours in offices utilise much of the daylight hours. Electric lighting costs, peak demand charges, and work interruptions during power brownouts can be greatly reduced by using daylighting. Daylight should be encouraged in office spaces because, not only would it save on energy, but it also carries immense physiological and psychological benefits. So, strategies for more daylight inclusion is needed for office interiors in context of any city which has a growing demand on electricity, far in excess of its production. This work started with a physical survey on offices located in different places of Dhaka to explore the current lighting practice and to identify key design issues where daylight could broadly enhance the luminous environment for offices. A pilot survey on a total number of 50 offices, determined by random sampling, was conducted. The survey covered a broad area through a questionnaire. During survey, importance was given on the surrounding context and external and internal elements of the offices that directly affect daylight inclusion into the office interiors and the overall luminous environment. The findings of survey helped to identify some problems on window configuration, sill height, lintel height, false ceiling, internal partition, blind configurations etc. Survey shows that lighting design in general is a neglected aspect of the overall design of spaces. Most of the cases it was found that the popular practice is against the common strategies of daylight. Survey also indicate that there is a considerable potential for more daylight inclusion into offices by some simple modification of the existing spaces and awareness about daylighting issues during the design phase. Recommended guidelines are specific to general problems found during survey, at the same time for introduction of building elements that were not found in Dhaka offices, e.g. light shelves, skylights etc. The author tried to draw simple recommendation that can be applied easily in any time from design phase to even after occupancy. It is expected that these suggestions will improve the luminous environment of offices of Dhaka under daylight

Incorporation of therapeutic effect of daylight in the architectural design of in-patient rooms to reduce patient length of stay (LoS) in hospitals

The biological need for lighting by an individual differs from the merely visual purpose, such as viewing objects and doing work or movement. Lack of adequate daylight for biological stimulation can lead to health problems, for e.g. imbalanced circadian rhythm. The importance of daylight is vital for hospital patients who are mostly physically and/or psychologically stressed. As, many patients stay indoors for 24 hours, they might be vulnerable to the lack of daylight which is necessary for health reasons. Hence, for hospital patients, daylight can be a strong therapeutic environmental design element to ensure good health and accelerate clinical recovery. The complex relationship between daylight environment and individuals responses are not fully understood. Controversy results that are debated by the previous researchers, has made the implementation of daylighting strategies in the architectural design of hospital in-patient rooms critical, mainly for therapeutic purpose. Strong evidence needs to be established that can build confidence to both architects and policy makers to use daylight for therapeutic purpose and integration of therapeutic effect of daylight to in-patient room architecture is necessary as well. This thesis provides information to architects (with examples) for incorporation of therapeutic effect of daylight in the design of in-patient rooms to reduce patient length of stay (LoS) in hospitals. A triangulation research method was applied in this work, where theories were developed qualitatively and tested quantitatively. Literature review was carried out to establish the potential effect of daylight on patient health. Retrospective field investigations were conducted to establish the quantitative relationship between daylight intensity and patient LoS inside in-patient rooms by developing Multiple Linear Regression (MLR) models under a general hospital environment. Using the daylighting goal to enhance therapeutic benefit for hospital patients, referred from literature and verified from field investigation data, a daylight design concept (sky window configurations) was developed and evaluated by prospective simulation study, and found better compared to traditional standard hospital window configurations, in order to enhance therapeutic benefit for hospital patients. A dynamic annual Climate-Based Daylight Modelling (CBDM) method that uses RADIANCE (backward) raytracer combined with a daylight coefficient approach considering Perez all weather sky luminance model (i.e. DAYSIM), was used for simulation analysis. This thesis develops strategies for architects to incorporate therapeutic effect of daylight in the architectural design of hospital in-patient rooms, including guidelines to support architectural decisions in case of conflicting situations, and to identify the range of daylight intensities within which patient LoS is expected to be reduced. The strategies also consider the ultraviolet radiation (UVR) protections and discuss the challenges of climate change for daylight researchers for the incorporation of therapeutic effect of daylight in the design of hospital in-patient rooms. The thesis provides a contribution to knowledge by establishing strong evidence of quantitative relationship between daylight and LoS, and by presenting new architectural forms for hospital in-patient room design as one of the possible ways to incorporate therapeutic effect of daylight in the design of hospital in-patient rooms effectively. It is expected that the research will encourage and help architects and policy makers to incorporate therapeutic effect of daylight in the design of hospital in-patient rooms, efficiently

Fully Fuzzy Linear System in Circuit Analysis with the Study of Weak Solution

In this paper, a simpler method to solve a fully fuzzy linear system (FFLS) with unrestricted coefficient matrix is discussed. FFLS is applied in circuit analysis instead of crisp linear system to reflect the real life situation much better. Arithmetic operations of triangular fuzzy number (TFN) are justified by forming FFLS in an electrical circuit with fuzzy sources and fuzzy resistors and then the system was solved by the simpler method. Finally, the case of weak solution is overcome by proposing a new definition of TFN. Keywords: Fuzzy number, Triangular fuzzy number, Fully fuzzy linear system, Circuit analysis, Weak solutio

First record of important biological parameters of Badis badis: A small indigenous species in Bangladesh

A total of 286 Badis badis were collected from the Sutiyahali Reservoir in Mymensingh from January to December 2022, and their sex ratios, first sexual maturity, length-weight relationships and condition factors were evaluated. The weight and length of B. badis varied from 0.81 to 1.01g (0.89±0.30) and 4.08 to 4.60cm (4.36±0.31), respectively. Logistic curves depicting a sex ratio and 50% maturity (L50) estimated at 4.5cm for females and 4.05cm for males, as well as males reaching first sexual maturity with a shorter length than females. Regression coefficients in every month differ significantly (p<0.05), according to the regression equations. Each month, the values of the exponent b were less than 3 (b<3), with the highest value of b recorded in August (2.80) and the lowest value recorded in January (2.33). This led to a monthly negative allometric growth being seen. A strong positive relationship is evident from the coefficient of determination (r2) values, which ranged from 0.92-0.98 with an average of 0.961. During the study, the average condition factor (Kn) value for B. badis was found to be 1.02±0.13, which is a positive indicator of the fish's physical well-being. The condition factor values varied between 0.84 to 1.39, making it abundantly clear that B. badis are in good health and the waterbody is an ideal habitat for their survival. Relative condition factor (Kr) values, which varied between studies and ranged from 0.78 to 1.01, also exhibited a noteworthy difference (p<0.05). For its long-term management, the above findings will be very helpful

Therapeutic daylight for hospital patients: a search for the benchmarks

To evaluate the therapeutic potential of daylit in-patient rooms, it is important to know the characteristics of daylight objectively (e.g. intensity and duration) which might support patient health effectively and are merely different from lighting requirements for visual purposes, such as viewing objects and doing work or movement. In the absence of a suitable standard, the upper and lower limits of daylight recommended by previous researchers to support patient health and comfort were selected for verification as the benchmarks of therapeutic daylight for hospital patients. Therapeutic daylight was defined as the level of daylight that can support patients to recover quickly. A field survey was conducted to collect real-world patient data from an existing hospital building. Clinical and demographic information were collected from hospital records. The amount of daylight that a particular patient might experience on the head during his/her stay in the bed was estimated by calculating the average ratio between two indoor data loggers: one installed at the back wall of patient bed (head side) and the other kept on vacant beds at the location of patient head. Based on the amount of daylight experienced, the sample patients were grouped under three categories and their post operative length of stay (LoS) inside in-patient rooms were compared using Multiple Linear Regression (MLR) analysis. The coefficient estimates of the developed MLR model (adjusted R square = 0.516, F = 40.931 (Sig. < 0.001)) shows that while holding the other explanatory variables constant (provision of outdoor view, rent of the rooms, mean arterial pressure, heart rate and diabetes mellitus), being in lower daylight group (below 190 lx) adds 42 hours (t=3.096, P value=0.002), and being in higher daylight group (above 2000 lx) adds 29 hours (t=2.094, P value<0.037) in patient post operative LoS in hospital rooms with respect to the group experienced the moderate levels of daylight (between 190 – 2000 lx). It was concluded that the range of 190 – 2000 lx can be regarded as effective daylight intensities within which positive health outcomes are more likely to occur, and architects could use this benchmark for therapeutic daylighting design

Smartphone-based Calorie Estimation From Food Image Using Distance Information

Personal assistive systems for diet control can play a vital role to combat obesity. As smartphones have become inseparable companions for a large number of people around the world, designing smartphone-based system is perhaps the best choice at the moment. Using this system people can take an image of their food right before eating, know the calorie content based on the food items on the plate. In this paper, we propose a simple method that ensures both user flexibility and high accuracy at the same time. The proposed system employs capturing food images with a fixed posture and estimating the volume of the food using simple geometry. The real world experiments on different food items chosen arbitrarily show that the proposed system can work well for both regular and liquid food items

Daylight simulation in architectural practice: shading design for hospitals in London

To achieve precision and satisfy the standards in daylight design, incorporation of computer based simulation tools during design development and decision making process could be useful. In addition to environmental factors several issues, such as construction and aesthetic, need to be considered concurrently during building projects which sometimes difficult to judge by simulation program in early stage of architectural design. To optimise time and achieve sensible design solutions this paper presents a case of therapeutic daylight shading design for an imaginary hospital in-patient room window configurations, located at London, where simulation guided results and other practical factors such as solar control criteria, line of vision, aesthetics and intuitive judgements of the authors were considered to meet the design goals. Though the simulation study is based on London climate, the principle of developing shading devices presented in this paper is also applicable for other types of building windows