IMPLEMENTATION OF VISIBLE LIGHT COMMUNICATION BASED SYSTEM FOR INDOOR POSITIONING

Visible light communication (VLC) is a green technology which is the replacement of the existing conventional radio frequency based indoor communication system. VLC system fundamentally comprises of a light source such as high brightness light emitting diodes (HBLEDs) that can accomplish dual function simultaneously i.e., illumination as well as data transmission. This paper presents a circuit design and analysis of PPM based VLC system and demonstrates the dimming control scheme. In this regard, front ends of the transmitter and the receiver were tested successfully by sending and consequently receiving equal width PPM frame via MATLAB. As it is known that dimming is an essential part of illumination and traditionally it is achieved by using pulse width modulation (PWM). Compared to PWM, PPM is facile to be applied since constant illumination level is easily achieved by PPM irrespective of data bits. The results show that either bits are (0000) or (1111) the illumination remained same i.e., 50% illumination level. Moreover, the VLC system with dimming support was tested for communication having 2m range. Article DOI: https://dx.doi.org/10.20319/mijst.2017.s31.178192 This work is licensed under the Creative Commons Attribution-Non-commercial 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.

People generally find themselves lost while visiting a new indoor location because they are unaware of the building’s architecture, especially when it is a large one or a shopping mall. The Global Position System (GPS) does not work properly in the indoor environment because of the satellite signal attenuation. In this paper, to assist people in finding their path, a Li-Fi (Light-Fidelity) based Indoor Positioning System (IPS) is proposed. A framework is developed based on a Li-Fi LED lamp transmitter and a dongle receiver connected to an Android smartphone to decode the received sequence. The pathfinding graph-based algorithm is proceeded in a REST architecture by a Web service consulting the graph-path database both installed on a Raspberry pi 4. The proposed solution is a low cost and does not require any additional infrastructure. It is easy to implement in most indoor environments like hospitals, buildings, and campuses. A short survey of techniques and algorithms for indoor positioning and navigation with the help of smartphones is also presented.

To provide services for other applications, promoting the availability of Global Positioning System (GPS)-is very important. While in the urban environments or with the high-power malicious interference, GPS signal is shaded by buildings or overwhelmed by interference. Hence the receivers may not acquire correct pseudo random noise (PRN) codes. Assisted GPS (A-GPS) technologies can solve the shaded problem, and antenna array with adaptive digital beam forming (ADBF) or spacetime adaptive processing (STAP) has been proved the effective methodology for interference suppressing. However, A-GPS may be not available, and the radio-frequency (RF) front end is too costly and cumbersome for a single customer. This paper investigates the collaborative navigation technology, utilizing GPS group users with dynamic Ad-hoc network and internal range measurements. Decentralized and distributed network architectures are presented for shading and interference presences, based on which user assistance and ambiguity removing for ADBF are proposed. Simulation results verify the performance improvement of the collaborative navigation based on dynamic Ad-hoc networking for different presences.

The Global Positioning System (GPS) has eventually become a common positioning technology. While GPS enabled many applications, satellite signals have yet to overcome many obstacles to enable indoor positioning. Meanwhile, due to the wide deployment of Wireless Local Area Networks (WLAN) in recent years, WLAN positioning algorithms have become popular for mobile device positioning in indoor environments. The most accurate WLAN positioning algorithms exploit the so-called fingerprinting concept which consists of two stages. In the offline stage (training), the Received Signal Strength Indicator (RSSI) from a set of available Access Points (AP) is measured for a number of reference locations and stored in a database. Due to the availability of many APs and the complex structure of indoor environments, this information is distinctive for each reference location and thus is called a position fingerprint. In the online stage (testing), a mobile device receives RSSIs from the APs and their fingerprint is compared to the fingerprints that are stored in the database for a best possible match. WLAN fingerprinting can provide high accuracy in indoor environments when there are many APs which ensure fingerprint uniqueness. This paper provides a novel approach to use WLAN multipath signals as possible fingerprints for positioning algorithms for applications with lower number of access points. The paper provides an initial study.

The Global Positioning System (GPS) is widely applied for outdoor positioning. However, GPS signals may degrade in an indoor environment. A nursing cart with a stable and accurate indoor positioning system inside is highly demanded in the hospital. The cart can be used for tracking the employees, or positioning movable medical devices. In this paper, we propose a Pedestrian Dead Reckoning (PDR) -based indoor positioning system with iBeacon calibrations. The proposed system can be implemented in resource- limited embedded device. To evaluate the property of the proposed system, real experiments under indoor environments have been conducted. The experimental results showed the effectiveness of the proposed approach. We also compared the impact of the number of iBeacons on positioning accuracy.

In large-scale commercial facilities, location information has much importance for visitor, administrator, and staff of facilities in order to provide various services such as navigation, information inquiry and response, recommendation, marketing analysis, and so on. In particular, indoor positioning and navigation are expected to be useful for visitors of the facilities, and the information of positioning result can be utilized for the analysis of marketing and demand control for the supply side of the commercial facilities. However, it is not easy to achieve indoor positioning and navigation, because there are some crucial problems, for example, it is difficult to apply Global Positioning System (GPS) technologies in indoor environments. In this chapter, we introduce an indoor autonomous positioning and navigation system without using the GPS technology. Some attractive features of the proposed system are that it can work on a smartphone as an application alone without server communications and can provide continuous positioning results. In addition to it, the system is robust against disturbances in real target environments. We have carried out some experiments of the system in a real large-scale commercial facility called Yokohama Landmark Plaza. A result of experiments shows that the positioning result can be obtained with high accuracy and that system can produce continuous positioning results in a robust way against noise and changes of radio wave strength in real environments. These properties will work effectively for providing the services mentioned above.

Precise indoor positioning is a widely researched topic currently. Many existing or new radio devices and standards are being explored for this purpose. Existing infrastructure or technology is always advantageous as it might reduce the cost and at the same time can be used for other purposes. The emerging visible light communication (VLC) is another technology being researched for precise positioning, especially in the indoor environment. VLC can be designed on existing infrastructure or slightly modified systems, and positioning using VLC would find usage in real-life scenarios. In this positioning system, an object whose location needs to be determined must have a VLC receiver. In this work, a comparative study is performed for popular algorithms through simulation as well as hardware demonstration. Thorough analysis and simulation are performed for circular lateration, hyperbolic lateration, differential detection, and angulation; the hardware implementation and demonstration as a proof of concept (POC) is completed for circular lateration and differential detection. Both these models use received signal strength (RSS) to calculate distances. We use a single photodetector for implementing circular lateration whereas two photodetectors for demonstrating differential technique. We observe that the differential detection performs relatively better compared to circular lateration, that is, the error is reduced in differential detection.

Since the well-established navigation systems such as GPS are ineffective in indoor environments, research into developing novel indoor positioning technologies has emerged in recent years. While several technologies are being investigated, a practical and reliable indoor positioning system is yet to emerge. Indoor positioning using light signals holds a great potential to provide a reliable solution to the indoor positioning problem. This paper presents a comprehensive review of the available literature on light-based indoor positioning systems. The paper establishes a classification based on the design of various light-based indoor positioning (LIP) systems, and discusses their key components including hardware, software and algorithms. The limitations and challenges of the LIP systems are discussed in details, and current published solutions are presented. The review also provides a comparison between LIP systems and other optical positioning systems, and identifies the associated research gaps. Finally, based on the identified gaps, the future research directions in both LIP systems and other optical positioning systems are presented.

Error compensation in indoor positioning systems based on software defined visible light communication

The purpose of this article is to discuss contemporary educational pedagogy for the 21st century adult student (commonly called andragogy) with attention to current learning styles theory. As the roles and responsibilities of current faculty continue to develop it is important to also focus on how learning styles theory and adult learning theory can be used to enhance andragogy in universities and colleges. This article will also address research on andragogy and its practical application to teaching, as well as student strategies for success. As the role of faculty continues to evolve, higher education needs to be responsible and responsive in preparing to address the diverse, contemporary and future challenges of the 21st teacher and student.&nbsp

Experiments were performed on the cold-formed steel C-section (CFS-CS) joints using the screw and adhesive material as the main subject of the study to assess the tensile stress-strain capacity. Since the connection has become the foremost aspect of the CFS-CS structure, a number of studies have been focusing to provide a better understanding with regard to the behavior of the connection. Even more so, further studies have also been carried out focusing on alternate solutions to improve the connection capacity. Considering all the above, this paper discusses the influence of varying types of connection on the tensile behavior of CFS-CS elements with particular using the self-drilling screw and 3M Scotch-weld DP810 as an adhesive material. The configurations of the screw(s) used in this study were 1, 2, and 3, while the percentages of adhesive material being used were 50%, 75%, and 100%. The results showed that the use of a higher amount of adhesive does not significantly increase the load capacity, but alleviate the failure condition. The results also showed that all test specimens satisfy the minimum requirement according to design specifications.

This phenomenological study explored the underlying framework on the establishment and sustainability of the Balay Paglaum (House of Hope) through the lived experiences of the stakeholders which served as informants and were selected based on their first-hand ideas on the challenges encountered and strategies employed to overcome difficulties and the binding realizations they gained throughout the process of establishing and sustaining the Balay Paglaum. Stakeholders used were from the Local Government Unit, Department of Education and Indigenous Peoples’ group. Based on their shared experiences 6 themes emerged and 21 clustered themes surfaced. With its establishment, the dropout rate problem of the Indigenous Peoples (IPs) was addressed and resolved. Commitment, love for the IP learners, enthusiasm of the leaders, believing the worth of the project and strong partnership made the Balay Paglaum become sustained and recognized as a shelter where hopes and dreams of the IPs are realized. It also served as the scaffold of the IP learners while pursuing their Basic Education. Article DOI: https://dx.doi.org/10.20319/pijss.2019.43.18761895 This work is licensed under the Creative Commons Attribution-Non-commercial 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.

Background: Hospital admissions are the leading cause of increasing healthcare budget and high demand of hospital utilisation in United Kingdom. There is limited information on the predisposing factors into hospital admission. This study systematically summarizes existing result from different studies in order to identify possible risk factors to hospital admission among patients in United Kingdom.Method/ Design: A systematic review of literature was carried out; identified relevant studies from searching through electronic database: Scopus, PubMed, Ethos, Cinahl, Cochrane, Reference list and other relevant reports.Discussion/ Outcome: Our inclusion criteria identified nine studies; using a predefined inclusion criterion, with factors such as: population setting, study design, risk factors, methodology, drawbacks and a systematically reviewed outcome. This study identified significant risk factors such as: older age, comorbidities, sex and deprivation. The review showed that identified risk factors are highly associated with hospital admission; thus early intervention on identified risk factors could reduce the rate of hospital admission in United Kingdom.

Light quality is one of the main factors that affect the productivity of cucumber plants, especially in induction of flowers. In this study, two lines of cucumber (Mercy and KE 27187) were treated with red (R), blue (B) and yellow (Y) light provided by LED (light emitting diode) with different compositions; RB (80:20) and RBY (80:10:10) for 8 h. Control plants were incubated under HPS lamps and TLD. The results showed that treatment of RB8 generate higher biomass and growth rate compared with RBY in both cucumber lines. Interestingly, RBY light increased sucrose content in plants, which positively correlate to the number of their female flowers. However, the energy efficiency of plants treated under LED light remains a major obstacle compared with control plants. Therefore, further research using appropriate PAR and light intensity of LEDs is needed to increase the productivity of female flowers in cucumbers. Article DOI: https://dx.doi.org/10.20319/mijst.2016.s11.1323 This work is licensed under the Creative Commons Attribution-Non-commercial 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.

Juvenile offenders are generally vulnerable to psychiatric illness. The objectives of the study were to determine the types of psychiatric disorders among male juvenile offenders in Bangladesh and to find out their socio-demographic correlation and relation with substance abuse. This was a cross-sectional study conducted in Juvenile Development Center (Boys’), Bangladesh. All the male offenders of 9-18 years were included in the study during January - June 2011. Total respondents were 138. Validated Bangla version of the Development and Well-Being Assessment (DAWBA) was used to determine psychiatric disorders which were assigned based on ICD-10 diagnostic criteria. Information regarding socio-demography and substance abuse were collected through face-to-face interview using a semi-structured questionnaire and from the case-notes. Data analysis was done by SPSS for windows 15 version. The mean (±SD) age of the respondents was 14.2 (±1.7) years. Psychiatric disorders were diagnosed in 57.2% of the respondents. The rate of emotional disorders (48.1%) was higher than behavioral disorders (38.4%). Regarding specific disorders, conduct disorder (46.8%)and major depressive disorder (43.0%) were the most common diagnoses. Statistically significant association of psychiatric disorders was found with the urban background (57.6%), primary level of education (63.5%), and employment (75.5%). Among the respondents, 38.4% had a history of substance abuse. Among the substance abusers, 77.4% had psychiatric disorders. It can be concluded that there was the considerable rate of psychiatric disorders and substance abuse among male juvenile offenders in the development center. Broad-based replication study could confirm these findings. Article DOI: https://dx.doi.org/10.20319/lijshls.2015.s11.161171 This work is licensed under the Creative Commons Attribution-Non-commercial 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.