Just Noticeable Difference Research Articles

Frequency dependence of sensitivity to interaural phase differences in pure tones.

It is well established that in normal-hearing humans, the threshold of interaural time differences for pure tones increases dramatically above about 1300 Hz, only to become unmeasurable above 1400 Hz. However, physiological data and auditory models suggest that the actual decline in sensitivity is more gradual and only appears to be abrupt because the maximum of the psychometric function dips below the threshold proportion correct, e.g., 0.794. Published data only report thresholds at certain proportions correct but not the decline of proportions correct or of the sensitivity index d' with increasing frequencies. Here, we present pure-tone behavioral data obtained with a constant stimulus procedure. Seven of nine subjects showed proportions correct above 0.9 at 1300 Hz and virtually no sensitivity at 1500 Hz (proportion correct within 0.07 of chance level). This corresponds to a sensitivity decline of 46-78 dB/oct, much steeper than predicted by existing models or by the decline of phase locking of the auditory nerve fibers in animal data.

Energy‐aware redundancy‐aware clustering in wireless sensor networks using Spined Loach Searching Optimization

SummaryWireless sensor networks play dominant role in data communication in many engineering applications and faces lot of challenges in its implementation. Energy conservation is also significantly required in these systems as the sensor nodes are battery operated. Hence, the energy efficient‐based technique needs to be implemented in data transmission. The most widely used methods are clustering‐based data transmission and energy efficient routing detection. In clustering, the proper selection of cluster head (CH) node is important to ensure energy balancing. The CH node should have more residual energy as it does many transmissions in the network. Moreover, the location of CH node should be nearer to all member nodes in the cluster. The clustering process must also perform the job of avoiding unnecessary transmissions. By considering these factors, the CH node can be optimally selected using Spined Loach Searching Optimization algorithm. The food searching behavior and environmental suitability for spiny loach fish living are deliberated to develop this bio‐inspired algorithm. In addition, the redundant transmissions inside the clusters can be reduced by employing a new technique called Least Difference Threshold Based Similarity Grouping. This work improves energy efficiency comparing with the conventional low energy adaptive clustering hierarchy protocol, and it is evaluated by setting the network in simulation environment. The network lifetime is increased; energy consumption, delay of transmission and the message cost are reduced.

Linear annular path damage probability distribution based ultrasonic guided wave method for position imaging and tracking of multi-damage on plate-like carbon fiber composite structure

Plate-like carbon fiber composite is an important component of the main bearing structure of spacecraft and high-speed trains, which has significant advantages in reducing the dead weight and energy consumption, and improving the carrying capacity. However, due to long-term exposure to complex service environments, material properties will be changed, these changes accumulated to a certain extent will lead to structural damage, threatening equipment operation and personal safety. To facilitate the attainment of mastering structural health states, this paper proposes a damage position imaging and tracking technology based on linear annular path damage probability distribution and ultrasonic guided wave for composite plate-like structures. Firstly, according to the dispersion curve, the propagation velocity characteristics of guided wave on composite structure are analyzed. Then, combined with the limited number of measured propagation velocities, the group velocity of the A0 mode in each direction is fitted. Based on the fitted velocity, the time-of-flight (TOF) map for all search points on each path can be pre-constructed. Subsequently, the damage TOFs and absolute TOF difference threshold are combined to obtain the annular damage probability distribution map of each sensing path. Ultimately, the total damage probability of the whole monitoring region is obtained by summing up the path damage probability, which can directly reflect the current damage position. Experimental results show that the proposed method has obvious advantages in imaging and tracking of single or multiple damage positions. It is hoped that the findings in this paper can provide new ideas for long-term damage state monitoring of the composite structures.

Just noticeable difference in sweetness perception of cola: Small changes in sugar are noticeable.

These data could help researchers and industry product developers know how much sugar can be reduced from a cola-flavored beverage before the change is apparent to consumers.

Development of a Thalassemia International Prognostic Scoring System (TIPSS)

A prognostic scoring system that can differentiate β-thalassemia patients based on mortality risk is lacking. We analysed data from 3145 β-thalassemia patients followed through a retrospective cohort design for the outcome of death. An a priori list of prognostic variables was collected. β Coefficients from a multivariate cox regression model were used from a development dataset (n = 2516) to construct a formula for a Thalassemia International Prognostic Scoring System (TIPSS) which was subsequently applied to a validation dataset (n = 629). The median duration of observation was 10.0 years. The TIPSS score formula was constructed as exp (1.4 × heart disease + 0.9 × liver disease + 0.9 × diabetes + 0.9 × sepsis + 0.6 × alanine aminotransferase ≥42 IU/L + 0.6 × hemoglobin ≤9 g/dL + 0.4 × serum ferritin ≥1850 ng/mL). TIPSS score thresholds of greatest differentiation were assigned as <2.0 (low-risk), 2.0 to <5.0 (intermediate-risk), and ≥5.0 (high-risk). The TIPSS score was a good predictor for the outcome of death in the validation dataset (AUC: 0.722, 95%CI: 0.641–0.804) and survival was significantly different between patients in the three risk categories (P < 0.001). Compared to low-risk patients, the hazard ratio for death was 2.778 (95%CI: 1.335–5.780) in patients with intermediate-risk and 6.431 (95%CI: 3.151–13.128) in patients with high-risk. This study provides a novel tool to support mortality risk categorization for patients with β-thalassemia that could help management and research decisions.

A basic identification of late auditory evoked potentials at infrasound frequencies: Support via neural network–based signal processing

Concerns about potential health risks from infrasound exposure require objective investigation methods for the perception of infrasound by humans. Neural-network methods were applied to identify weak infrasound evoked potentials and to investigate the efficacy of these techniques. Two simple networks – a fully connected three-layer feed-forward network and a two-layer autoencoder – were designed for the analysis of electroencephalography (EEG) data recorded in response to infrasound stimuli presented. Late auditory evoked potentials (LAEPs) were detected and correlation factors between the target and the output of the networks were determined to assess the differentiation ability of the two networks. Both networks were able to differentiate infrasound evoked potentials from noise but showed different performance levels with respect to a differentiation threshold. The results can be applied to objectively identify perception events by infrasound in humans.

Short-Term Efficacy of Using a Novel Low-Volume Bone Marrow Aspiration Technique to Treat Knee Osteoarthritis: A Retrospective Cohort Study.

Intra-articular bone marrow concentrate (BMC) and aspirate (BMA) injections have been used with mixed results to treat osteoarthritis (OA). Given the various aspiration and concentration methods available for preparing bone marrow, more data are needed to identify the optimal bone marrow harvesting techniques to treat OA. This retrospective cohort study examined the effect of using low-volume BMAs harvested using the Marrow Cellution™ (MC) device on 160 patients (262 knees) suffering from pain due to knee OA, KL grades 2-4, that did not respond to conservative treatment. Changes in visual analog scores (VAS) for overall daily activity were examined over a six-month time frame in these patients (63.5 ± 0.97 years of age; 48.1% male). In addition, changes in the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Patient Global Impression of Change (PGIC scores) were examined over the same time frame in a smaller subset of patients (95 patients including 172 knees). There was a statistically significant improvement in VAS scores for overall daily activity 6 months postprocedure in the study population, 7.29 ± 0.27 vs. 3.76 ± 0.34 (p < 0.0001), as well as statistically significant improvements in WOMAC scores, 49.3 ± 4.27 vs. 66.3 ± 4.08 (p < 0.0001). On the individual level, 71% of the cases displayed VAS improvements and 61% of the cases displayed WOMAC improvements that exceeded levels previous studies determined to be the minimal clinically important difference (MCID) for knee OA treatments. The improvements in WOMAC scores were also seen in both the WOMAC pain subscore, 52.2 ± 4.39 vs. 72.2 ± 4.36 (p < 0.0001) and the WOMAC function subscore, 51.6 ± 4.67 vs. 69.0 ± 4.36 (p < 0.0001). In addition, the PGIC scores measuring patient satisfaction improved from 4.03 ± 0.26 at 6 weeks postprocedure to 4.65 ± 0.28 at 6 months postprocedure (p < 0.0001). Knee OA patients treated with MC BMA intra-articular injections exhibited significant reductions in VAS pain scores and significant improvements in WOMAC scores that exceeded the minimal clinically important difference thresholds. In addition, reductions in VAS pain scores and improvements in WOMAC scores correlated with higher PGIC scores.

Grasping follows Weber's law: How to use response variability as a proxy for JND.

Weber's law is a fundamental psychophysical principle. It states that the just noticeable difference (JND) between stimuli increases with stimulus magnitude; consequently, larger stimuli should be estimated with larger variability. However, visually guided grasping seems to violate this expectation: When repeatedly grasping large objects, the variability is similar to that when grasping small objects. Based on this result, it was often concluded that grasping violated Weber's law. This astonishing finding generated a flurry of research, with contradictory results and potentially far-reaching implications for theorizing about the functional architecture of the brain. We show that previous studies ignored nonlinearities in the scaling of the grasping response. These nonlinearities result from, for example, the finger span being limited such that the opening of the fingers reaches a ceiling for large objects. We describe how to mathematically take these nonlinearities into account and apply this approach to our own data, as well as to the data of three influential studies on this topic. In all four datasets, we found that-when appropriately estimated-JNDs increase with object size, as expected by Weber's law. We conclude that grasping obeys Weber's law, as do essentially all sensory dimensions.

Detection and discrimination of electrical stimuli from an upper limb cuff electrode in M. Mulatta

Objective. Peripheral nerve interfaces seek to restore nervous system function through electrical stimulation of peripheral nerves. In clinical use, these devices should function reliably for years or decades. In this study, we assessed evoked sensations from multi-channel cuff electrode stimulation in macaque monkeys up to 711 d post-implantation. Approach. Three trained macaque monkeys received multi-channel cuff electrode implants at the median or ulnar nerves in the upper arm. Electrical stimuli from the cuff interfaces evoked sensations, which we measured via standard psychophysical tasks. We adjusted pulse amplitude or pulse width for each block with various electrode channel configurations to examine the effects of stimulus parameterization on sensation. We measured detection thresholds and just-noticeable differences (JNDs) at irregular, near-daily intervals for several months using Bayesian inferencing from trial data. We examined data trends using classical models such as Weber’s Law and the strength-duration relationship using linear regression. Main results. Detection thresholds were similar between blocks with pulse width modulation and blocks with pulse amplitude modulation when represented as charge per pulse, the product of the amplitude and the pulse width. Conversely, Weber fractions—calculated as the slope of the regression between JND charge values and reference stimulus charge—were significantly different between pulse width and pulse amplitude modulation blocks for the discrimination task. Significance. Weber fractions were lower in blocks with amplitude modulation than in blocks with pulse width modulation, suggesting that pulse amplitude modulation allows finer resolution of sensory encoding above threshold. Consequently, amplitude modulation may enable a greater dynamic range for sensory perception with neuroprosthetic devices.

Abstract 13444: Acute Anemia With Mechanical Circulatory Support; Unmasking the Culprit

Introduction: Mechanical circulatory support (MCS) is known to potentiate hemolytic anemia. Nevertheless, patients are also at an increased risk of spontaneous bleeding due to anticoagulation or post-procedural complication. We present two cases of acute anemia due to spontaneous retroperitoneal bleeding following insertion of the Impella assist device. Case Presentation: Two male patients aged 65 and 74 presented with cardiogenic shock secondary to ischemic cardiomyopathy with a low ejection fraction of 10% and 15%). Both patients initially had an intra-aortic balloon pump (IABP) inserted. Because of progressively deteriorating hemodynamics, IABP was switched to the Impella 5.5 device through the axillary artery. Following insertion of the Impella, they developed anemia requiring multiple blood transfusions. Despite repositioning of Impella, hemoglobin continued to drop prompting further workup. CT abdomen/pelvis revealed left retroperitoneal hematoma. CT angiogram showed active bleeding from the left L3 lumbar artery in one patient and multiple foci of active arterial extravasation in the other patient. Coil embolization was performed, achieving hemostasis and stabilization of hemoglobin levels in both patients. Discussion: Hemolytic anemia associated with the use of the Impella that improves with repositioning or device removal is well known and documented. However, patients with MCS are also at increased risk of spontaneous bleeding due to procedural injury and the use of anticoagulation. We report 2 cases with retroperitoneal bleeding from the lumbar artery diagnosed a few days after the placement of Impella. The occurrence of retroperitoneal hemorrhage was possibly spontaneous due to anticoagulation along with Impella-induced hemolysis resulting in acute anemia. Neither patient had any vascular access through the left groin making post-procedural complications less likely. The concealed nature and non-specific symptoms of retroperitoneal bleed can lead to a delay in diagnosis. Early identification and control of bleeding can prevent fatal outcomes. Conclusion: Our cases highlight the importance of clinicians having a broad differential and low threshold to investigate other causes of anemia in patients with MCS.

Abstract 13818: Health System Integrated Measurement-Based Care Using Patient-Reported Outcomes Assessment in Lower-Extremity Peripheral Artery Disease

Introduction: Peripheral artery disease (PAD) is a chronic disease that requires continuous and individualized disease-management to optimize patients’ symptoms, function and quality of life. Directly capturing patient-reported outcomes (PROs) in routine practice has the potential to increase the patient-centeredness of PAD care. We designed and implemented a system to measure health status within the workflow of a vascular specialty clinic. Methods: In a large academic center, from February 2020 until March 2022, an in-person patient navigation system (Yale PRO-QI) supported by a online data collection workbench was implemented to collect the EQ-5D, Peripheral Artery Questionnaire (PAQ), and VascuQol-6 as part of the outpatient consultations for lower-extremity PAD. Completion rates by month, and domain and summary scores for each PRO were derived per clinical phenotype: new patient/pre-procedural patient, post-procedural/follow-up patient. Results: Of 1071 eligible patient visits, 841 PRO assessments (n=446 unique patients) were completed, for an overall completion rate of 78.5% (monthly completion range 56.4%-100.0%). Patients had a mean age of 70.5±10.2 years, 39.4% were female, 9.6% Hispanics, 14.6% blacks, and 74.7% whites. Of the PROs administered, only the Symptom Stability, Treatment Satisfaction, and Quality of Life subscales of the PAQ were able to discriminate between the clinical phenotypes with differences that reached the minimal clinically important difference threshold of ~10 points ( Figure ). Conclusions: In anticipation of measurement-based care metrics that assess quality of care benchmarks for patient-centered PAD care, our health system integrated PRO workflow had a high response rate, and was able to successfully discriminate between highly symptomatic vs. stable patients as measured by validated disease-specific PRO benchmarks for PAD treatment success.

Mid-Term Outcomes of the All-Soft Quadriceps Tendon Autograft Are Noninferior to Hamstring Autograft in Primary Anterior Cruciate Ligament Reconstruction: Comparison With Minimum 5-Year Follow-Up

The purpose of this study was to compare the 5-year clinical and functional outcomes of the soft tissue quadriceps tendon (QT) to those of the hamstring tendon (HT) autograft METHODS: A retrospective review of patients undergoing ACL reconstruction using either soft tissue QT or double tendon HT autograft with at least 5 years of follow up was conducted. Surgical technique included anteromedial portal creation for the femoral tunnel and transtibial technique for the tibia. Graft fixation was achieved with interference composite screws for the QT and combination of interference composite screw and suture button for the HT cohort. The two groups were compared for differences in outcomes including International Knee Documentation Committee (IKDC) score, Lysholm score, return to sport, and complications. A total of 37 patients with QT autograft and 46 HT autografts were included in the study with a mean follow up of 69.9 months and 70.9 months, respectively. The QT group demonstrated a larger graft size on average (9.64mm vs. 7.90mm, p <0.001). The IKDC and Lysholm scores were similar between the two groups at 2-years postoperatively. At 5-years postoperatively, the QT group demonstrated significantly greater IKDC (p 0.018) and Lysholm (p 0.007) scores. The cohorts demonstrated similar rates of achieving minimal clinically important difference (MCID) thresholds at both 2 and 5 years postoperatively. The two groups also demonstrated comparable rates of return to sport, time to return, and postoperative complications. Although the QT autograft demonstrated increased patient reported outcome scores when compared to the HT at 5-years postoperatively, there was no clinically significant difference between the cohorts at 2 or 5 years postoperatively. The QT autograft is an effective alternative to HT autograft with non-inferior results to the hamstring autograft at mid-term follow up. Retrospective Comparison Study; Level of Evidence III LEVEL OF EVIDENCE: III, retrospective cohort study.

Identification and Classification of Aluminum Scrap Grades Based on the Resnet18 Model

In order to reduce the elemental species produced in the recycling and melting of aluminum scrap and to improve the quality of pure aluminum and aluminum alloys, it is necessary to classify the different grades of aluminum scrap before melting. For the problem of classifying different grades of aluminum scrap, most existing studies are conducted using laser-induced breakdown spectroscopy for identification and classification, which requires a clean and flat metal surface and enormous equipment costs. In this study, we propose a new classification and identification method for different grades of aluminum scrap based on the ResNet18 network model, which improves the identification efficiency and reduces the equipment cost. The objects of this research are three grades of aluminum scrap: 1060, 5052, and 6061. The surface features of the three grades were compared using a machine vision algorithm; three different datasets, using RGB, HSV, and LBP, were built for comparison to find the best training dataset for subsequent datasets, and the hyperparameters of learning rate and batch size were tuned for the ResNet18 model. The results show that there was a differentiation threshold between different grades through the comparison of surface features; the ResNet18 network model trained the three datasets, and the results showed that RGB was the best dataset. With hyperparameter optimization of the ResNet18 model, the accuracy of final classification and recognition could reach 100% and effectively achieve the classification of different grades of aluminum scrap.

Research on transformer condition evaluation based on oil chromatography differentiation threshold

As one of the important power transmission and transformation equipment, the reliability of transformer is directly related to the safe operation of power system. At present, the on-line monitoring technology based on dissolved gas analysis in oil is widely valued by researchers all over the world because it can continuously monitor the operation status of transformers and timely and effectively find the early faults of transformers. In this paper, the on-site oil chromatography data are differentiated and classified according to the voltage level of the transformer. The curve fitting method is used for statistical analysis and to build a distribution model. The cumulative probability is associated with the defect rate and failure rate of the equipment, and the corresponding threshold value is obtained by using the inverse cumulative distribution function as the attention value and warning value. By using this method, the attention values of the volume fraction of dissolved gas in oil and the gas production rate of dissolved gas in the existing national standards are improved, and the corresponding warning values are calculated to make the warning mechanism more flexible and reliable.

A comparative study of trait anxiety between female weightlifters and powerlifters

The aim of the study was to compare and wanted to see the sports competition anxiety between weightlifting and powerlifting. Sixty-eight female weightlifters and powerlifters (4 from each body weight category) who had participated in weightlifting and Powerlifting All India Inter University competition were selected as subject for the study. The participants were between the ages of 18 to 25. The Sports Competition Anxiety Test (SCAT) questionnaire designed by Martin (1990) was employed in this study. According to the literature review and researchers knowledge it was hypothesized that there might be significant difference between female weightlifters and powerlifters. For the analysis of the data independent‘t’ test was applied. The significant difference threshold was chosen at 0.05. There was no substantial difference between weightlifters and power lifters, according to the study's findings.

Indicators of subjective audiometry in the conventional frequency range in patients with COVID-19

Sensorineural deafness (SND) is a polyetiological disease. The cause of perceptual hearing loss can be, among other things, viral infections. As a result of the pandemic of the SARS-CoV-2 virus, a significant number of patients with various clinical manifestations of the disease COVID-19 are observed, among which there are lesions of the central nervous, cardiovascular, and other systems. In addition, in the publications of researchers, there are reports of damage to the auditory analyzer. However, there is not enough information in the literature regarding the study of hearing function in patients with COVID-19. The purpose of the study is to assess the state of auditory function according to subjective audiometry data in the conventional frequency range in pat ients with COVID-19. Materials and methods: An analysis of subjective audiometry data in the conventional frequency range was conducted on 36 patients with COVID-19 who complained of hearing impairment after the disease. The examination was performed using audiometers AS-40 (Interacoustics, Denmark) and MA-31 (Germany). Results and their discussion: To determine the indicators of subjective audiometry in patients with perceptual disorders of auditory function during COVID-19, we examined patients with complaints of decreased auditory function. Among 147 patients with COVID-19, during the survey, 51 people (34.7%) indicated certain disorders of the auditory system. During the instrumental examination of 47 patients with COVID-19 with complaints of hearing loss, we mainly observed sensorineural disorders of auditory function (36 people, 76.6%). Therefore, we analyzed subjective audiometry data in these patients. In most cases, we observed a gently descending type of tonal audiometric curve with the greatest increase in hearing thresholds for tones in the high-frequency region of the conventional range. The analysis of quantitative indicators of tone audiometry showed a significant increase in hearing thresholds for tones in the studied patients with COVID-19 compared to individuals of the control group. In patients with COVID-19, there is a significant (p&lt;0.01) increase in hearing thresholds to tones, starting at 2 kHz, compared to controls. This increase was most pronounced at frequencies of 6 and 8 kHz, where the values were 31.2±1.5 and 34.5±1.9 dB, respectively. Note that we did not find any significant differences in speech audiometry indicators in the studied patients compared to the indicators of the control group. However, some patients (7 people, 19.4%) complained of an inevitable deterioration in speech intelligibility. Moreover, three patients (8.3%) indicated that speech intelligibility impairment during communication occurred to them periodically. Also, we did not detect any significant changes in the indicators of suprathreshold tests – Lüscher intensity differential threshold test and SiSi test in the studied patients. Although at the same time, some patients (8 people, 22.2%) complained about poor tolerance of loud sounds, which may indicate the presence of FPZH (the phenomenon of accelerated increase in loudness), and, therefore, the presence of receptor damage to the auditory analyzer. Therefore, a third of patients (34.7%) may have a decrease in hearing function with the disease of COVID-19. Damage to the auditory system mainly (76.6% among all cases of hearing impairment) manifests as perceptual disturbances. Therefore, when examining patients suffering from COVID-19, we believe detecting disorders in the auditory system is advisable. Consequently, conducting an instrumental examination for those with hearing impairment complaints is advisable. On the other hand, when presenting patients with sensorineural deafness, it should be borne in mind that this may be related to a previous illness of COVID-19. Conclusions: 1. With COVID-19, a third of patients (34.7%) experience auditory function impairment due to damage to the auditory system, mainly perceptual in nature – 76.6% among all hearing impairment cases. 2. Hearing disorders in the case of COVID-19 can be observed directly during the disease, but more often, such manifestations appear somewhat delayed from the onset or after a particular time after the disease. 3. The most pronounced significant (p&lt;0.01) increase in hearing thresholds to tones in pat ients with COVID-19 with hearing impairment, compared to controls, occurs at frequencies of 6 and 8 kHz, where the values were 31.2±1.5 and 34.5±1.9 dB, respectively. 4. Patients with COVID-19 who have complaints of hearing impairment should undergo an instrumental audiological examination, first of all, subjective audiometry.

Robust watermarking based on blur‐guided JND model for macrophotography images

Macrophotography Images (MPIs) have recently emerged as an active topic due to the development of mobile phone camera technology. A large number of MPIs have been rapidly increasing in many rich visual services, such as smartphones or high-definition monitors. MPIs are often composed of sharp macroimage and blur background, which exhibit different perceptual properties that often lead to different just noticeable difference (JND) estimation. Inspired by this, we formulate the blur concealment (BC) as another factor to determine the total masking effect: the interaction is relatively straightforward with a limited masking effect in the sharp regions, and is complicated with a strong masking effect in the blur parts. Furthermore, texture and orientation adaption and color information weighting are separately incorporated into the contrast masking and color masking. Finally, considering both BC and masking effects, a novel robust watermarking framework based on the proposed blur-guided JND model for MPIs, targeting at further improving the MPIs copyright protection performance. Extensive experiments on MP2020 and Blur Detection data sets show that the applicability of the proposed JND model in the scenario of perceptually MPIs watermarking, and our proposed scheme can outperform the state-of-the-art watermarking schemes by providing better robustness performance at the uniform visual quality.

Pulse width and intensity effects of pulsed electric fields on cancerous and normal skin cells

Microsecond pulsed electric fields (PEF) have previously been used for various tumour therapies, such as gene therapy, electrochemotherapy and irreversible electroporation (IRE), due to its demonstrated ability. However, recently nanosecond pulsed electric fields (nsPEF) have also been used as a potential tumor therapy via inducing cell apoptosis or immunogenic cell death to prevent recurrence and metastasis by interacting with intracellular organelles. A large proportion of the existing in-vitro studies of nsPEF on cells also suggests cell necrosis and swelling/blebbing can be induced, but the replicability and potential for other effects on cells suggesting a complicated process which requires further investigation. Therefore, this study investigated the effects of pulse width and intensity of nsPEF on the murine melanoma cells (B16) and normal murine fibroblast cells (L929) through electromagnetic simulation and in-vitro experiments. Through examining the evolution patterns of potential difference and electric fields on the intracellular compartments, the simulation has shown a differential effect of nsPEF on normal and cancerous skin cells, which explains well the results observed in the reported experiments. In addition, the modelling has provided a clear evidence that a few hundreds of ns PEF may have caused a mixed mode of effects, i.e. a ‘cocktail effect’, including cell electroporation and IRE due to an over their threshold voltage induced on the plasma membrane, as well as cell apoptosis and other biological effects caused by its interaction with the intracellular compartments. The in-vitro experiments in the pulse range of the hundreds of nanoseconds showed a possible differential cytotoxicity threshold of electric field intensity between B16 cells and L929 cells.

Automated Mapping of Flood Inundation Areas using Cloud Based Processing Tools of Google Earth Engine for Efficient Disaster Management – A Case Study of Kerala Floods

Availability of reliable information on extent and impact of flood becomes critical for faster and efficient disaster management planning. Access to near realtime satellite data from optical and microwave sensors on Google Earth Engine (GEE) platform helps in rapid flood inundation mapping. Also, integration of Optical and Synthetic Aperture Radar (SAR) data from Sentinel series of satellites helps in detection of landuse/landcover features like Built-up, Agriculture Lands and Water bodies under flooding. The GEE platform provides extensive library tools for simultaneous pre-processing of SAR images and cloud free optical images from multiple satellites. In this research, Differential Thresholding and Differential Smoothening algorithms developed in GEE have been applied on Pre and Post SAR images for automatic identification of flood inundation areas. The inundated areas thus delineated were validated with inundation extents provided by the National Database for Emergency Management (NDEM). The methodology of automation developed in this study is applied to severe floods occurred in Kerala, India during August 2018. The sensitivity of polarization on mapping accuracy is estimated using Vertical- Horizontal (VH) and Vertical-Vertical (VV) modes available with Sentinel-1 data. The result indicates that VV mode of polarization provides better accuracy of 96% than VH mode. The coding is implemented in GEE environment with automation to provide extent of flood inundation for efficient management and mitigation planning during flood disasters.

Evaluation of Perceptual Difference in Dynamic Projection Mapping with and without Movement of the Target Surface

High-frame-rate visual feedback has been proven effective for projection mapping on quickly moving targets. However, the quantitative conditions of frame rates have not been elucidated. In particular, considering that the human dynamic visual acuity generally declines as the moving target velocity increases, it may be argued that the tracking accuracy required for projection mapping on moving targets can be lower than that required for fixed targets. To examine the above-mentioned conditions of frame rates, this study compares them based on two types of projection mapping systems having equivalent relative movements to each other: projection mapping from a fixed projector/camera system to a moving target and projection mapping from a moving projector/camera system to a fixed target. We examined the effects of the target movements by having stationary observers visually recognize and evaluate them. Using the weighted up-down method, we measured the frame time that provides a just noticeable difference (JND) to the projection mapping. We found that when the visual feedback is generated at a frame time of 2 ms, the frame time that provides a JND is 3.72 ms on average for fixed targets and 3.94 ms on average for moving targets: a 1%-level significant difference. Taking the individual differences and experimental errors into account, this is not a very large variation. This suggests that, in projection mapping to moving targets, we should realize a tracking accuracy as precise as that in projection mapping to fixed targets.