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Brain-computer interface (BCI) enables us to interact with the external world via electroencephalography (EEG) signals. Recently, deep learning methods have been applied to the BCI to reduce the time required for recording training data. However, more evidence is required due to lack of comparison. To reveal more evidence, this study proposed a deep learning method named time-wise convolutional neural network (TWCNN), which was applied to a BCI dataset. In the evaluation, EEG data from a subject was classified utilizing previously recorded EEG data from other subjects. As a result, TWCNN showed the highest accuracy, which was significantly higher than the typically used classifier. The results suggest that the deep learning method may be useful to reduce the recording time of training data. [ABSTRACT FROM AUTHOR]

The crystallographic growth, magnetic properties, microstructure, and recording performance of CoCrPt–SiO2 perpendicular magnetic recording media on RuCoCr type of intermediate layers were systematically investigated. Excellent Co (00•2) crystallographic texture with dispersion Δθ50 as low as 3.2° could be obtained on the RuCoCr as the grain isolation layer, whereas the Δθ50 on the pure Ru grain isolation layer was 3.9°. Upon injecting oxygen into the RuCoCr layer via reactive sputtering and at high sputter pressures, grain center-to-center distance as small as 5.9 nm with a distribution of about 13% was achieved. The Δθ50 deteriorated on the RuCoCr-oxide type of intermediate layers, however, it remained comparable to that on the pure Ru layers. Signal-to-noise ratio also increased on the RuCoCr-oxide grain isolation layers due to the decreased grain sizes. The effectiveness of the RuCoCr-oxide type of intermediate layers toward grain size reduction and in improving the performance of perpendicular magnetic recording media is discussed. [ABSTRACT FROM AUTHOR]

The role of substrate bias during the sputter deposition of various layers of double-layered CoCrPt-SiO2 perpendicular recording media has been investigated in order to understand the physical mechanisms behind the various effects observed. Perpendicular recording media with dual Ru intermediate layers were investigated using several magnetic and microstructural characterization techniques. It was observed that, in general, the application of a bias voltage during the deposition of the seedlayer (Ta) and the first intermediate layer (Ru) is helpful in reducing the c-axis dispersion of the recording layer. For the other layers, application of bias voltage leads to deterioration in the magnetic properties. It was also observed that the application of a bias voltage during the deposition of the first intermediate layer (especially Ru) may not enhance the preferred growth of Ru hexagonal-close-packed (00.2) planes parallel to the disk surface, as predicted before. However, the bias voltage on the Ru layer still reduces the c-axis dispersion of the magnetic layer. From the omega-offset x-ray diffraction investigations, it is estimated that the lattice parameter “a” of the Ru layer is reduced slightly with bias voltage, which could probably lead to a reduction in the lattice mismatch between the Ru layer and Co-alloy layer. Bias conditions also could lead to improved interface condition. Such an improvement in the lattice matching or interface conditions could probably be the cause of the reduction of c-axis dispersion of the recording layer. [ABSTRACT FROM AUTHOR]

The physics of the playback process in perpendicular recording is explored. It is shown that due to the existence of effectively two layers of the “magnetic charges” in a perpendicular medium, the stray field sensed by a reader rolls off with the areal density essentially differently than it does in longitudinal recording. Comparing three recording modes, longitudinal recording and perpendicular recording without and with a soft underlayer (SUL), at equivalent conditions, with a 10 nm thick recording layer at a bit aspect ratio of 1:1, the density roll-off is the fastest for the longitudinal mode, while it is the slowest for the perpendicular mode without a SUL. It is shown that although at relatively low linear and track densities the use of a SUL increases the playback signal, the signal does not depend on the use of a SUL at high densities. It is shown that for both perpendicular modes, although at sufficiently low track densities (below ∼50 ktpi) the signal disappears at relatively low linear densities, there is a significant nonzero signal even at zero linear density if the track density is sufficiently high (above ∼300 ktpi). Using the magnetic image model, it is shown that, fundamentally, the use of a SUL could not improve the resolution of a recording system. As an example, the Reciprocity Principle is utilized to analyze and compare four different reader designs. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The inter-track interference (ITI) can severely degrade the system performance of bit-patterned media recording (BPMR). One way to alleviate the ITI effect is to encode an input data sequence before recording to avoid some data patterns that easily cause an error at the data detection process. This paper proposes a constructive ITI (CITI) coding scheme for a multi-track multi-head BPMR system to eliminate the data patterns that lead to severe ITI. Numerical results indicate that the system with CITI coding outperforms that without CITI coding, especially when an areal density (AD) is high and/or the position jitter is large. Specifically, for the system without position jitter at bit-error rate of 10-4, the proposed scheme can provide about 3 dB gain at the AD of 2.5 Tb/in.2 over the system without CITI coding. [ABSTRACT FROM AUTHOR]

The change in magnetization at the transition and the transition noise of the stacked media recorded with a single pole head without a trailing shield (SPH) and a head with a trailing shield (TSH) were investigated by using micromagnetic simulation. As a result, it was found that the linearity of the transition was higher and the transition noise was lower for the medium recorded with the TSH as compared with the medium recorded with the SPH. This is because stronger in-plane recording field of the TSH caused many small reversed domains. The relation between the magnetization distribution of the transition area and the direction of the recording head field reflected the relation between the domain structure of demagnetized media and the direction of the demagnetizing field. [ABSTRACT FROM AUTHOR]

Recording in bit patterned media (BPM) requires strict synchronization of the signal misregistration time. A scheme is presented based on micromagnetic simulation of a single element which allows defining a writing window (WW) permitting for synchronized recording. The WW behavior for random distributions of the anisotropy field is studied. The width of WW is shown to be determined by the medium parameters deviations, the BPM element separation, and the head field strength. It is shown that significant limitations can be imposed on the BPM density and required head fields because of the random distributions of the BPM properties. [ABSTRACT FROM AUTHOR]

Simulations of thermally assisted recording were carried out to determine the effect of the temperature dependence of Hk and thermal gradients on the recording performance. Even in the absence of a head field gradient, it was possible to record sharp transitions in the media. The relationship between Ms(T) and Ku(T) and its influence on signal-to-noise ratio (SNR) was investigated, and it was discovered that media in which Ku(T)∝Ms3(T) had higher SNR and narrower written tracks than materials with Ku(T)∝Ms2(T). [ABSTRACT FROM AUTHOR]

We demonstrate the near-field optics on granular recording media calculated by finite difference time domain (FDTD). Granular media and pattern media are necessary for hybrid recording to achieve a recording density of 1 Tbit/in.2. In FDTD simulation, the power of near-field optics from a plasmon antenna is affected by the presence of the medium. However, for further investigation, the model of this study included granular media. The grains are arrayed in a close-packed structure. From this analysis, the top of the grains shows strong power of near-field optics. The power intensity of the granular media under the apex of the plasmon antenna shows a narrow distribution with a sharp peak, about three times higher than that for film media. There are higher peaks in intensity at the surface of the grain than inside the grain. These results show that grains positioned at the apex of the antenna can be heated by a small, concentrated spot. [ABSTRACT FROM AUTHOR]

This paper addresses parameter identification of signals that are smooth and have compact support, but are otherwise arbitrary. We propose a definition of the time reference that results in the time uncertainty estimates that are much smaller than what one might expect with a casual analysis. These estimates are easily calculable given the noise level of the recording device and the signal shape. [ABSTRACT FROM AUTHOR]

In-vehicle recording devices have enabled recent changes in methodological paradigms for traffic safety research. Such devices include event data recorders (EDRs), vehicle black boxes (VBBs), and various sensors used in naturalistic driving studies (NDSs). These technologies may help improve the validity of models used to assess impacts on traffic safety. The objective of this study is to analyze the injury severity in taxi-pedestrian crashes using the accurate crash data from VBBs, such as the time-to-collision (TTC), speed, angle, and region of the crash. VBB data from a two-year period (2010–2011) were collected from taxis operating in Incheon, South Korea. An ordered probit model was then applied to analyze the injury severity in crashes. Five variables were found to have a greater effect on injury severity: crash speed, crashes in no-median sections, crashes where the secondary impact object of pedestrians was the crash vehicle, crashes where the third impact object of pedestrians was another moving vehicle, and crashes where the third impact region of pedestrians was their head. However, injuries were less severe in crashes where the first impact region on the pedestrian was their leg, crashes with the car moving in a straight line, and crashes involving junior high school students. [ABSTRACT FROM AUTHOR]

In recent years several projects collecting toponyms have been carried out in the Gorenjska region. The projects focused on the recording of the dialectal form of toponyms and their use among local population. The article presents and draws attention to the significant differences between common uses of geographical names at the local level and formal use of names collected in the Slovenian national Register of Geographical Names, which consequently appear on official maps. [ABSTRACT FROM AUTHOR]

Hall effect measurement has been used to detect the perpendicular and in-plane magnetization components simultaneously in a [Co/Pd][SUBn] multilayer thin film with strong magnetic anisotropy along the direction perpendicular to the film plane. The angle between the driving current direction and the in-plane projection of the applied magnetic field was varied to investigate the contribution of in-plane magnetization component to the measured Hall voltage. Hall voltage under the canted magnetic field revealed that the output is the superposition of the anomalous Hall effect (AHE) due to the perpendicular component of magnetization and the planar Hall effect (PHE) due to the in-plane magnetization component. Odd symmetry characteristics of AHE and even symmetry characteristics of PHE with respect to applied field have been applied to extract the Hall voltage contributed by the two different magnetization components from their combined characteristic. Anomalous Hall voltage from the perpendicular magnetization component exhibited an irreversible hysteresis loop while that from the in-plane magnetization component was found almost reversible with respect to applied magnetic field. The method was effective to evaluate the in-plane component of magnetization in an ultrathin film under the canted magnetic field. [ABSTRACT FROM AUTHOR]

We have successfully demonstrated longitudinal recording at areal density of 130 Gb/in[SUP2] at a data rate as high as 170 Mbps (21 MB/s) and at a bit-aspect-ratio (BAR) of 2.9, using merged inductive-write/spin-valve-read heads on low noise thin film disks. The heads were fabricated with the standard photolithography and wafer pole trimming used in our currently available commercial products. The reader is a bottom synthetic spin valve (BSSV) with a 0.09 μm gap, and the writer has a conventionally trimmed pole with 0.09 μm gap. The reader magnetic read width (MRW) was measured at 0.10 μm. At read bias of sim; 4 mA we measured reader sensitivity as high as 20 mV/μm. The write head was also optimized for tracks as narrow as 0.14 μm operating at overwrite (OW) of 36 dB and nonlinear transition shift (NLTS) better than -25 dB at 610 kBPI, without precomp. Using conventional media we measured total spectral SNR ∼ 18 dB. The media to electronics noise ratio was 4.8, showing that we are still operating in a media noise limited system. Low-flying air bearing surface (ABS) design and advanced pole tip recession (PTR) control were required to achieve magnetic spacing of about 15 nm. [ABSTRACT FROM AUTHOR]

The results of angular measurements of the remanent switching fields for granular longitudinal and perpendicular magnetic recording media are presented and compared to idealized models of magnetic switching. Co alloy longitudinal and perpendicular recording media are found primarily to have a Stoner-Wohlfarth switching character at vibrating sample magnetometer time scales. Since the Stoner-Wohlfarth model does not consider the effects of thermal activation, the angular dependence of the time independent switching field H[SUBswro](θ) was determined from a Sharrock analysis. This approach shows a closer agreement between experimental data and model. For the case of a representative high density longitudinal recording medium, we additionally investigate the switching field distribution. [ABSTRACT FROM AUTHOR]

2 nm metal seed layers (M = Al, Cu, Ni, Cr, Ag, Mg, Fe, Co, Pd, Au, Pt, Mo, and Hf) were sputtered to increase coercivity (H[SUBc]) and anisotropy (K[SUBu]) of CoCrPt/Ti perpendicular recording media.) Among them 2 nm Ag seed layer was very effective to increase H[SUBc] of (Co[SUB78]Cr[SUB22])[SUB100-x]Pt[SUBx]/Ti(x = 14,20). However, the effect was more pronounced when (Co[SUB78]Cr[SUB22])[SUB100-x]Pt[SUBx] films became thinner. In addition α[= 4π(dM/dH)[SUBH[SUBc]]] decreased when the Ag layer was used. The film thickness below H[SUBc] which the seed Ag layer was effective was reduced with decreasing Pt content. However, x-ray diffraction data showed that the Ag seed layer did not promote (002) texture of Ti and CoCrPt layers. In magnetic force microscope observations, domain size was reduced when the Ag seed layer was used. The reason for the higher coercivity of CoCrPt films with the Ag seed layer is thought to be due to change of exchange constant of the grains, for which the grain boundary area plays an important role. Effects of film thickness and Pt content can also be explained successfully by the variation of exchange constant due to grain boundary. [ABSTRACT FROM AUTHOR]

In this study, the effects of CoCrPtTa and CoCrPtB magnetic intermediate layers (ILs) on the magnetic properties and read/write performance of CoCrPt/soft magnetic layer perpendicular recording media were investigated. Even though the perpendicular coercivity of the media with these ILs was reduced by 500 Oe, these media still showed a low exchange slope of 1.4 and a large negative nucleation field of about -1000 Oe. Additionally, the reduced grain size of the media with these IL was observed by transmission electron microscopy. From the read/write test, these media with ILs showed improved performance of 3-5 dB higher signal-to-noise ratio and overwrite ratio (OW) compared to the media without ILs. These enhancements could be attributed to the reduction of grain size of the magnetic layer and weakening of the intergranular interaction between grains by insertion of the IL. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated the effect of the switching rate dependence of dynamic remanent coercivity on recording performance in magnetic recording systems. Measurement technique; Experimental results; Conclusions.

Presents information on a study which made measurements using various head-media combinations of the variation of the media jitter with recorded track width in magnetic recording systems. Theory and experimental method; Results and discussion; Conclusions.

Presents information on a study which examined the effects of write head pole shapes, disk anisotropy and write current on erase bands and hooks in recording systems. Impact of erase bands and hooks for high tracks per inch (TPI) applications; Experimental setup and results; Conclusions.

This article offers a set of methodological reflections from the research process of the doctoral thesis, Contexts of life, psychosocial and sociocultural factors of adolescents co - opted by criminal organizations in the city of Saltillo, Coahuila. The author shares, from her own research experience, the use of different research techniques developed in an ethnographic context within the Center for Integration, Diagnosis and Treatment of Male Adolescents in the City of Saltillo, Coahuila, where she cohabited with teenage offenders who were co -opted by criminal organizations in Mexico. It also allows us to know in this process of knowledge, the instruments of registration designed precisely for this research, as well as their impressions around this experience. For the purposes of his doctoral thesis, the research is considered from the Human Development Ecology Theory of Urie Bronfenbrenner (1987). [ABSTRACT FROM AUTHOR]

This article reviews the Electronically Activated Recorder (EAR) as an ambulatory ecological momentary assessment tool for the real-world observation of daily behavior. Technically, the EAR is an audio recorder that intermittently records snippets of ambient sounds while participants go about their lives. Conceptually, it is a naturalistic observation method that yields an acoustic log of a person's day as it unfolds. The power of the EAR lies in unobtrusively collecting authentic real-life observational data. In preserving a high degree of naturalism at the level of the raw recordings, it resembles ethnographic methods; through its sampling and coding, it enables larger empirical studies. This article provides an overview of the EAR method; reviews its validity, utility, and limitations; and discusses it in the context of current developments in ambulatory assessment, specifically the emerging field of mobile sensing. [ABSTRACT FROM AUTHOR]

There are increasing needs for self-applicable methods assessing sleep in clinical and non-clinical settings. This study aimed to investigate the inter-scorer reliability for the sleep stage scoring and for the sleep variable assessments in the portable electroencephalography (EEG) and electro-oculography (EOG) recording system. Sleep recordings were performed simultaneously with polysomnography (PSG) and portable EEG/EOG recordings in 14 healthy adults. The inter-scorer concordance of the sleep stage scoring was assessed in the two recording methods. Sleep variables were compared between the two methods using the Bland-Altman plots in each scorer. The overall inter-scorer concordance rate of sleep stage scoring for the EEG/EOG data was 85.5 %, and the Cohen's κ was 0.80 ( p < 0.001), being equivalent to those for the PSG data (89.2 %, 0.85, p < 0.001) while that for StageN1 was relatively low (EEG/EOG 60.1 %, PSG 71.7 %). In both scorers, Bland-Altman plots showed that the mean difference between sleep variables obtained from the two systems was within the acceptable range although the inter-class correlations between the two systems were lower for StageN2 or StageR in either scorer. Although the results suggest that the sufficient inter-scorer reliability can be obtained with the EEG/EOG recording system based on manual sleep stage scoring in healthy young adults, the nature of the EEG/EOG recording system can influence the precisions in manually assessing sleep architectures in comparison to PSG. [ABSTRACT FROM AUTHOR]

Background: Assessing the range and territories of wild mammals traditionally requires years of data collection and often involves directly following individuals or using tracking devices. Indirect and non-invasive methods of monitoring wildlife have therefore emerged as attractive alternatives due to their ability to collect data at large spatiotemporal scales using standardized remote sensing technologies. Here, we investigate the use of two novel passive acoustic monitoring (PAM) systems used to capture long-distance sounds produced by the same species, wild chimpanzees (Pan troglodytes), living in two different habitats: forest (Taï, Côte d'Ivoire) and savanna-woodland (Issa valley, Tanzania). Results: Using data collected independently at two field sites, we show that detections of chimpanzee sounds on autonomous recording devices were predicted by direct and indirect indices of chimpanzee presence. At Taï, the number of chimpanzee buttress drums detected on recording devices was positively influenced by the number of hours chimpanzees were seen ranging within a 1 km radius of a device. We observed a similar but weaker relationship within a 500 m radius. At Issa, the number of indirect chimpanzee observations positively predicted detections of chimpanzee loud calls on a recording device within a 500 m but not a 1 km radius. Moreover, using just seven months of PAM data, we could locate two known chimpanzee communities in Taï and observed monthly spatial variation in the center of activity for each group. Conclusions: Our work shows PAM is a promising new tool for gathering information about the ranging behavior and habitat use of chimpanzees and can be easily adopted for other large territorial mammals, provided they produce long-distance acoustic signals that can be captured by autonomous recording devices (e.g., lions and wolves). With this study we hope to promote more interdisciplinary research in PAM to help overcome its challenges, particularly in data processing, to improve its wider application. [ABSTRACT FROM AUTHOR]

Recording systems to acquire electroencephalogram (EEG) data are traditionally lab-based. However, there are shortcomings to this method, and the ease of use and portability of emerging wireless EEG technologies offer a promising alternative. A previous validity study demonstrated data derived from a single-channel, wireless system (NeuroSky ThinkGear, San Jose, California) is comparable to EEG recorded from conventional lab-based equipment. The current study evaluated the reliability of this portable system using test-retest and reliable change analyses. Relative power (RP) of delta, theta, alpha, and beta frequency bands was derived from EEG data obtained from a single electrode over FP1 in 19 healthy youth (10–17 years old), 21 healthy adults (18–28 years old), and 19 healthy older adults (55–79 years old), during eyes-open, eyes-closed, auditory oddball, and visual n-back conditions. Intra-class correlations (ICCs) and Coefficients of Repeatability (CRs) were calculated from RP data re-collected one-day, one-week, and one-month later. Participants' levels of mood and attention were consistent across sessions. Eyes-closed resting EEG measurements using the portable device were reproducible (ICCs 0.76–0.85) at short and longer retest intervals in all three participant age groups. While still of at least fair reliability (ICCs 0.57–0.85), EEG obtained during eyes-open paradigms was less stable, and any change observed over time during these testing conditions can be interpreted utilizing the CR values provided. Combined with existing validity data, these findings encourage application of the portable EEG system for the study of brain function. [ABSTRACT FROM AUTHOR]

The article offers information on the relationship between atmospheres and moods and its impact on architecture. Topics discussed include table with recording instruments and cables that extend to the area of testing; strict regulation of corporeal activity and sensory stimulation through minimal architecture removed the emergence of any atmosphere; and views of philosopher Martin Heidegger on moods as atmospheres.

Provides information on a study that examined factors that influence the recorded magnetization in the perpendicular recording process. Information on an analytical model of the recording process; Details on analytical results; Conclusions.

Provides information on a study that analyzed high linear density in perpendicular recording having a negative transition width. Details on the analysis; Discussion of the analysis; Conclusions.

Investigates the sensitivity of partial response maximum likelihood (PRML) and peak detection channels on the read/write performance of a recording system. Peak shift and PW50 evaluation parameters for peak detection channel; Nonlinear transition shift.

Investigates the basic properties of the proposed Preisach accommodation properties of recording media on a commercial flexible disk material. Accommodation in Preisach models; Experimental analysis of accommodation in recording media.

Presents a study that investigated domain size changes due to thermal relaxation after high laser power irradiation on amorphous TbFeCo films. Information on mark edge recording; Erase/write cyclability for mark edge recording of rare-earth-rich and transition-rich TbFeCo disks; Dependence of the normalized writing power versus erase/write cycles.

Capturing symptom/rhythm correlation is crucial in patients who have rhythm-related symptoms. Evolving technology has led from 24 hour and 14 day Holter monitors to now external loop recorders to capture symptom/rhythm correlation. In patients with very infrequent and short-lived symptoms, the only recourse is an implantable recording device. Recently, patient activated recording devices have become available. These have the potential to significantly increase the duration for monitoring symptom/rhythm correlations. We report cases of using such devices to demonstrate some of the uses and challenges of this new ECG recording technology. [ABSTRACT FROM AUTHOR]

This work focuses on the topic of melodic characterization and similarity in a specific musical repertoire: a cappella flamenco singing, more specifically indeblaandmartinetestyles. We propose the combination of manual and automatic description. First, we use a state-of-the-art automatic transcription method to account for general melodic similarity from music recordings. Second, we define a specific set of representative mid-level melodic features, which are manually labelled by flamenco experts. Both approaches are then contrasted and combined into a global similarity measure. This similarity measure is assessed by inspecting the clusters obtained through phylogenetic algorithms and by relating similarity to categorization in terms of style. Finally, we discuss the advantage of combining automatic and expert annotations as well as the need to include repertoire-specific descriptions for meaningful melodic characterization in traditional music collections. [ABSTRACT FROM PUBLISHER]

The effect of timber length on time-of-flight acoustic longitudinal measurements was investigated on the structural timber of four Spanish species: radiata pine (Pinus radiata D. Don), Scots pine (Pinus sylvestris L.), laricio pine (Pinus nigra Arn.), and maritime pine (Pinus pinaster Ait.). Time-of-flight longitudinal measurements were conducted on 120 specimens of dimensions 90 × 140 mm using three commercially available acoustic instruments (Sylvatest Duo, USLab, and Microsecond Timer). Time-of-flight data were initially obtained from the full-length (4 m) specimens, and then from the specimens cut to 3, 2, and 1 meter in length by successively cutting off 0.5 m from each end. The acoustic longitudinal velocity of the timber specimens of different lengths was also measured using a resonance-based acoustic method. The apparent acoustic longitudinal velocity for all species increased linearly as the timber length decreased from 4 to 1 meter. Acoustic velocity determined from time-of-flight data was significantly higher than the acoustic velocity determined using the resonance method, indicating systematic measurement errors associated with the time-of-flight instruments. Empirical models were developed for the relationships between time-offlight measurements on timber specimens and timber lengths in the range of 1 to 4 m. Finally, a procedure was proposed to correct the timeof- flight data. [ABSTRACT FROM AUTHOR]

The article presents a hardware and software complex for ground tests of onboard charged particle spectrometers that are designed at the National Research Nuclear University MEPhI for monitoring of nuclear-physical factors of space weather and can be installed in a wide class of satellites. The structural scheme and operating principles of component parts are discussed. The main algorithm and software features are presented. The technique of ground spectrometer tests and calibrations in various measurement modes at atmospheric cosmic particle flows, both in autonomous laboratories and in interface tests as part of a satellite, is also described. [ABSTRACT FROM AUTHOR]

In this paper we discuss the use of the Hilbert-Huang transform (HHT) to enhance the time-frequency analysis of microtremor measurements. HHT is a powerful algorithm that combines the process of empirical mode decomposition (EMD) and the Hilbert transform to compose the Hilbert- Huang spectrum that contains the time-frequency-energy information of the recorded signals. HHT is an adaptive algorithm and does not require the signals to be linear or stationary. HHT is advantageous for analyzing microtremor data, since observed microtremors are commonly contaminated by nonstationary transient noises close to the recording instruments. This is especially true when microtremors are measured in an urban environment. In our data processing HHT was used to (1) eliminate the unwanted short-duration transient constituents from microtremor data and use only the coherent portion of the data to carry out the widely used horizontal to vertical spectral ratio (H/V) method; (2) identify and eliminate the continuous industrial noise in certain frequency band; and (3) enhance the H/V analysis by using the Hilbert-Huang spectrum (HHS). The efficacy of this proposed approach is demonstrated by the examples of applying it to microtremor data acquired in the metropolitan Beijing area. [ABSTRACT FROM AUTHOR]

A photovoltaic (PV) system has been widely deployed in residential areas to reduce energy cost. However, it is not monitored in detail or managed in a user-friendly manner in many cases. Therefore, a PV monitoring system needs to provide both detailed monitoring of each PV module and a user-friendly way of access to the monitored data. In addition, the PV monitoring system needs to be low-cost to be widely deployed. To achieve these needs, this paper proposes a user-friendly PV monitoring system based on a low-cost power line communication (PLC). For cost reduction, the PLC module is developed without a communication modem. For detailed monitoring, the PLC modules are installed at each PV module; the data logger aggregates the monitored data of each PV module and the PV inverter. For userfriendly access, a smart app is used to show the aggregated data graphically. In the field test, the developed PV monitoring system is installed at a real PV system composed of sixteen 400 W PV module; users can figure out the status of the whole PV system through a smart device. This scheme is expected to reduce energy cost in residential areas by maintaining a PV system performance. [ABSTRACT FROM AUTHOR]

The purpose of this article is to throw into radical doubt the material-discursive practices of recording devices (e.g., tape and digital recorders) used in qualitative interviews. To do this work, I first present a Baradian diffractive reading, a reading across epistemological and ontological differences that matter, of recording devices in qualitative research. I explore how recording devices have become a normalized material-discursive practice in which recording devices are both part of and result from an objectivist epistemology and realist ontology. Then, I share four irruptive moments from my study about family history genealogists’ use of objects (e.g., photographs, documents, and artifacts) that called into question such a material-discursive practice. Last, I situate recording devices in Barad’s agential realism, an onto-epistemological framework in which recording devices intra-act with humans, nonhumans, culture, and discourse to generate entangled meanings and knowledge in a constantly shifting world(s). [ABSTRACT FROM PUBLISHER]

We have developed a complete 100 kHz ultrasonic recording system. The primary components of the system are a SensComp Series 600 Instrument Grade Electrostatic Transducer, custom printed circuit board (PCB), wide-bandwidth instrumentation amplifier, linear-phase filter, fully differential 16-bit analog to digital converter (ADC) sampling at 840 kHz, 168 MHz STM32F4 32-bit microcontroller, and a direct 100 Mbps Ethernet connection. A host computer running a custom application written in C++ provides a unified computer interface that allows the user to control all aspects of the system and provides a real time spectrogram. The system is designed for general use but has been initially used to study the ultrasonic vocalizations of rodents. We demonstrate the system by recording a well-established call made by Long-Evans rats termed50-kHzvocalizations. The system was also designed with possible physical measurements in mind, e.g., distance, temperature, humidity, and gas mixture ratios. [ABSTRACT FROM AUTHOR]

Neuronal microcircuits are formed of a myriad of spatially and functionally specific cell classes. Despite the importance of the spatial component in the characterisation of neural circuits, it has not received the attention it deserves. While multi-electrodes are widely used in the study of microcircuits, the spatial information available from them remains largely unexploited for analysis beyond spike sorting. Here we show how the spatial pattern of the extracellular signal is determined by both the electrophysiology and morphology of neurons. Starting from known current source models for the generation of the extracellular potential, we use the spatial pattern observed across a multi-electrode array to localise and classify neurons into putative morphological classes. We evaluated the localisation and classification models with low fitting errors in simulated data. When applying them to recorded data we found correspondence between localisation statistics and expected recording radius and found evidence to support the separation into putative morphological classes. While existing localisation methods do not hold for the recording distances expected on multi-electrode recordings (under 60 μm), classification methods have been limited to the temporal component by either characterising spike shape or firing patterns. We show here how the information available from extracellular recordings can be used to localise and classify neurons based on the spatial pattern seen by multi-electrode arrays. Together they can improve current characterisation and classification of neurons based on complementary criteria such us firing pattern and functional characterisation. [ABSTRACT FROM AUTHOR]

With enabling of a thermal actuator, an air bearing slider can fly at sub-nanometer level spacing on a magnetic disk while the recording elements are functioning. At such spacing, the slider stability and head-disk interface reliability remains to be understood. In this study, a novel understanding on dynamics of the MEMS thermal flying-height control (TFC) slider in touchdown process is developed. By using average and variational-iteration methods, closed-form spectrum estimations of slider vibration are derived. The derived formulation offers an insight of the relationship between spectrum and interface parameters. Physics-based simulation is also conducted to quantify the spectrum of slider vibrations as a function of varied interfacial parameters. To further extend the analytical and numerical analysis, the experimental study of a TFC slider while flying on a rotating disk at sub-nanometer spacing are performed. The analysis reveals the dominance of the air bearing force among other interfacial forces at sub-nanometer spacing. [ABSTRACT FROM AUTHOR]