Indoor navigation systems based on data mining techniques in internet of things: a survey

© 2018, Springer Science+Business Media, LLC, part of Springer Nature. Internet of Things (IoT) is turning into an essential part of daily life, and numerous IoT-based scenarios will be seen in future of modern cities ranging from small indoor situations to huge outdoor environments. In this era, navigation continues to be a crucial element in both outdoor and indoor environments, and many solutions have been provided in both cases. On the other side, recent smart objects have produced a substantial amount of various data which demands sophisticated data mining solutions to cope with them. This paper presents a detailed review of previous studies on using data mining techniques in indoor navigation systems for the loT scenarios. We aim to understand what type of navigation problems exist in different IoT scenarios with a focus on indoor environments and later on we investigate how data mining solutions can provide solutions on those challenges

A GapWaveguide-Fed Wideband Patch Antenna Array for 60-GHz Applications

This communication presents a wideband aperture-coupled patch antenna array based on ridge gap waveguide feed layer for 60-GHz applications. The novelty of this antenna lies in the combination of relatively new gap waveguide technology along with conventional patch antenna arrays allowing to achieve a wideband patch antenna array with high gain and high radiation efficiency. An 8 x 8-element array antenna is designed, fabricated, and tested. Experimental results show that the bandwidth of VSW

60-GHz Groove Gap Waveguide Based Wideband H-Plane Power Dividers and Transitions: For Use in High-Gain Slot Array Antenna

Wideband design of power dividers, T-junctions, and transitions based on groove gap waveguide (GGW) technology is presented in this paper with the goal to use these components in high-gain millimeter-wave antenna array design at 60-GHz frequency range. Since this GGW technology does not require electrical contact between the different metal layers of a complex 3-D waveguide structure, the fabrication cost and mechanical complexity are decreased. The designed T-junctions and different power dividers exhibit wide operational bandwidth and low output power and phase imbalance over the 60-GHz frequency band. Also, two transitions from GGW to a standard rectangular waveguide have been designed. To validate the performance of the designed components, a 64-way power divider in combination with 256 radiating slots is designed, prototyped, and measured at 60-GHz band. Measurement results agree well with the simulated performance of the complete array antenna, and the antenna gain is more than 32.5 dBi. The total radiation efficiency is more than 80% over the operating frequency range from 57 to 67 GHz. Also, the measured sidelobe levels are found to be agreeing well with the simulated level

Ridge gap waveguide slot antenna array with 30% bandwidth for 60-GHz applications

This paper presents a wideband high efficiency slot antenna array based on ridge gap waveguide technology at 60 GHz for millimeter-wave applications. The antenna sub-array consists of four radiating slots that are excited by a cavity. Some tuning pins are placed inside the cavity to achieve wideband performance. A 4 74 slots array antenna is designed using 4-ways power divider. The proposed structure exhibits 30% impedance bandwidth (|S11

A Ridge Gap Waveguide fed apperture-coupled microstrip antenna array for 60 GHz applications

This paper deals with the design of patch antenna arrays with Ridge Gap Waveguides (RGW) feed networks at 60-GHz band. An array of 64 radiating elements are designed and simulated to demonstrate the good performance of the proposed array. The proposed antenna shows the gain up to 22.6 dBi, efficiency higher than 80% and an impedance bandwidth of 13% covering 59-67 GHz. The results are valuable for the design and evaluation of wideband planar antenna arrays at millimeter-wave frequencies

Antibiotic resistance pattern and distribution of psla gene among biofilm producing pseudomonas aeruginosa isolated from waste water of a burn center

Background: Pseudomonas aeruginosa is considered as a major cause of hospital-acquired infections due to its high antibacterial resistance. Biofilm formation is a well-known pathogenic mechanism in P. aeruginosa infections, since sessile bacteria are protected in an extracellular matrix of exopolysaccharide. The expression of polysaccharide synthesis locus (pslA gene) can be important for biofilm formation by P. aeruginosa. Objectives: The purpose of this research was to evaluate the antibiotic resistance pattern and distribution of the pslA gene among biofilm-producing P. aeruginosa isolates obtained from waste water of Burn Centre in Guilan, Iran. Materials and Methods: Fifty isolates of P. aeruginosa were obtained from waste water of a burn center. The P. aeruginosa isolates were identified using standard bacteriological procedures. Drug susceptibility test was performed by disk diffusion method for all the isolates against nine antimicrobial agents. Biofilm formation was measured by microtiter plate assay. Polymerase chain reaction (PCR) was used to identify the presence of the pslA gene among the isolates. Results: Biofilm formation was observed in 70 of the P. aeruginosa isolates. The potential formation of biofilm was significantly associated with resistance to gentamicin, imipenem, tobramycin and piperacillin. In addition, the pslA gene only existed in biofilm-producing isolates with a frequency of 42.9 (n = 15).Conclusions: The findings of the present study well demonstrated that the P. aeruginosa biofilm-producing isolates were more resistant to the tested antibiotics. Furthermore, because of wide distribution, it seems that the pslA gene is associated with biofilm formation. � 2015, Ahvaz Jundishapur University of Medical Sciences

Association between plasma tau and postoperative delirium incidence and severity: a prospective observational study

BACKGROUND: Postoperative delirium is associated with increases in the neuronal injury biomarker, neurofilament light (NfL). Here we tested whether two other biomarkers, glial fibrillary acidic protein (GFAP) and tau, are associated with postoperative delirium. METHODS: A total of 114 surgical patients were recruited into two prospective biomarker cohort studies with assessment of delirium severity and incidence. Plasma samples were sent for biomarker analysis including tau, NfL, and GFAP, and a panel of 10 cytokines. We determined a priori to adjust for interleukin-8 (IL-8), a marker of inflammation, when assessing associations between biomarkers and delirium incidence and severity. RESULTS: GFAP concentrations showed no relationship to delirium. The change in tau from preoperative concentrations to postoperative Day 1 was greater in patients with postoperative delirium (P<0.001) and correlated with delirium severity (ρ=0.39, P<0.001). The change in tau correlated with increases in IL-8 (P<0.001) and IL-10 (P=0.0029). Linear regression showed that the relevant clinical predictors of tau changes were age (P=0.037), prior stroke/transient ischaemic attack (P=0.001), and surgical blood loss (P<0.001). After adjusting for age, sex, preoperative cognition, and change in IL-8, tau remained significantly associated with delirium severity (P=0.026). Using linear mixed effect models, only tau (not NfL or IL-8) predicted recovery from delirium (P<0.001). CONCLUSIONS: The change in plasma tau was associated with delirium incidence and severity, and resolved over time in parallel with delirium features. The impact of this putative perioperative neuronal injury biomarker on long-term cognition merits further investigation. CLINICAL TRIAL REGISTRATION: NCT02926417 and NCT03124303

Adult ADHD screening scores and hospitalization due to pedestrian injuries: A case-control study

Background: The aim of this study was to investigate the association between adult ADHD screening scores and hospitalization due to pedestrian injuries in a sample of Iranian pedestrians. Methods: Through a case-control study, a case population of 177 pedestrians injured by the vehicles in road traffic crashes were compared with 177 controls who lacked a record of intentional or unintentional injuries enrolled from various wards of Imam Reza University Hospital which is a specialty teaching hospital located in the same city with similar referral level. The cases and controls had an age range of 18-65 years and were matched on gender and age. ADHD symptom profile was assessed using the Persian Self-report Screening Version of the Conner's Adult ADHD Rating Scales (CAARS-S:SV). The association of ADHD screening score and pedestrian injuries was investigated using multiple binary logistic regression to investigate the independent effect of ADHD index score on belonging to case group. Both crude and adjusted odds ratios were reported. Results: Men comprised 86.4 of the study subjects. The crude odds ratios for all the four ADHD subscales to be associated with pedestrian injuries were 1.05, 1.08, and 1.04 for the subscales A (attention deficit), B (hyperactivity/impulsiveness) and ADHD index respectively. However, the association for subscale A was not statistically significant with a borderline p-value. The final multivariate analysis showed that variables associated with pedestrian injuries in the road traffic crashes were ADHD Index score (OR = 1.06, 95 CI: 1.01-1.12); economic status (including household income and expenditure capacity); educational level and total walking time per 24 h. Conclusions: Adult ADHD screening score can predict pedestrian injuries leading to hospitalization independently from sex, age, economic status, educational level and pedestrian exposure to traffic environment (average walking time). © 2020 The Author(s)

Cohort study of electroencephalography markers of amyloid-tau-neurodegeneration pathology

Electroencephalography signatures of amyloid-β, tau and neurodegenerative pathologies would aid in screening for, tracking progression of, and critically, understanding the pathogenesis of dementia. We hypothesized that slowing of the alpha peak frequency, as a signature of hyperpolarization-activated cyclic nucleotide gated ‘pacemaker’ channel activity, would correlate with amyloid and tau pathology burden measured by amyloid (Pittsburgh Compound B) and tau (MK-6240) positron emission tomography or CSF biomarkers. We also hypothesized that EEG power would be associated with neurodegeneration (CSF neurofilament light and hippocampal volume). Wakeful high-density EEG data were collected from 53 subjects. Both amyloid-β and tau pathology were associated with slowing in the alpha peak frequency [Pittsburgh Compound B (+) vs. Pittsburgh Compound B (−) subjects, P = 0.039 and MK-6240 (+) vs. MK-6240 (−) subjects, P = 0.019]. Furthermore, slowing in the peak alpha frequency correlated with CSF Aβ42/40 ratio (r2 = 0.270; P = 0.003), phosphoTau (pTau181, r2 = 0.290; P = 0.001) and pTau181/Aβ42 (r2 = 0.343; P < 0.001). Alpha peak frequency was not associated with neurodegeneration. Higher CSF neurofilament light was associated with lower total EEG power (r2 = 0.136; P = 0.018), theta power (r2 = 0.148; P = 0.014) and beta power (r2 = 0.216; P = 0.002); the latter was also associated with normalized hippocampal volume (r2 = 0.196; P = 0.002). Amyloid-tau and neurodegenerative pathologies are associated with distinct electrophysiological signatures that may be useful as mechanistic tools and diagnostic/treatment effect biomarkers in clinical trials