Channel Positioning Research Articles

Application and Previous Report of External Channel Positioning System in Enlarged Foraminoplasty

Application and Previous Report of External Channel Positioning System in Enlarged Foraminoplasty

Method of precise sensing channel positioning forϕ-OTDR-based DAS

For the applications of distributed acoustic sensing technology (DAS), such as leakage detection in a pipeline, it is important to precisely identify the sensing channels along a optic fiber to correctly locate the vibrations and improve the accuracy of DAS. A method of precise sensing channel positioning for DAS is proposed. An experimental validation is conducted in consideration of optic fiber types and soil types. A bending element was inserted into the sand and clay to excite the constant-frequency signals point by point along the optic fiber. A DAS interrogator was used to collect the vibrations of the fiber. The average of the normalized time-domain signals and the amplitude of the specific constant frequency in the frequency domain are analyzed. The parameters of the skewness of the amplitude-channel curve (SACC) and the relative shift of the amplitude peak (RSAP) are proposed to identify the boundary of the adjacent sensing channels. The accuracy of the sensing channel positioning is better than the spacing of the excitation points.

Research on Visible Light Channel Modeling and Positioning in Irregular Scenes

Research on Visible Light Channel Modeling and Positioning in Irregular Scenes

Extracellular Hydraulic Resistance Enhances Cell Migration.

Cells migrating in vivo encounter microenvironments with varying physical properties. One such physical variable is the fluid viscosity surrounding the cell. Increased viscosity is expected to increase the hydraulic resistance experienced by the cell and decrease cell speed. The authors demonstrate that contrary to this expected result, cells migrate faster in high viscosity media on 2‐dimensional substrates. Both actin dynamics and water dynamics driven by ion channel activity are examined. Results show that cells increase in area in high viscosity and actomyosin dynamics remain similar. Inhibiting ion channel fluxes in high viscosity media results in a large reduction in cell speed, suggesting that water flux contributes to the observed speed increase. Moreover, inhibiting actin‐dependent vesicular trafficking that transports ion channels to the cell boundary changes ion channel spatial positioning and reduces cell speed in high viscosity media. Cells also display altered Ca2+ activity in high viscosity media, and when cytoplasmic Ca2+ is sequestered, cell speed reduction and altered ion channel positioning are observed. Taken together, it is found that the cytoplasmic actin‐phase and water‐phase are coupled to drive cell migration in high viscosity media, in agreement with physical modeling that also predicts the observed cell speedup in high viscosity environments.

An unsolvable power flow adjustment method for weak power grid based on transmission channel positioning and deep reinforcement learning

To solve the problem of human resources and time consumption caused by unsolvable power flow of weak power grid, an adjustment method for unsolvable power flow based on weak transmission channels and deep reinforcement learning (DRL) is proposed. Weak horizontal and vertical channels are defined, and their relationship with unsolvable power flow is demonstrated. Then, based on the idea of reducing the load level first and then gradually recovering it, actionable device and action margin are determined based on transmission channel positioning, adjustment sensitivity and solvability degree, so as to form a power flow adjustment strategy. Next, the Markov decision-making process of power flow adjustment is constructed, the prior probability of action is given by adjustment sensitivity of the actionable device, and the action is mapped to the adjustment amounts of generators and capacitors/reactors. Based on soft actor-critic, a DRL model suitable for power flow adjustment is established. Finally, the simulation results show that the proposed method performs well both in the New England 39-bus standard system and an actual power grid of China. Compared with the results obtained by other methods, the superiority of the proposed method is verified.

Method of Precise Sensing Channel Positioning for Das Based on the Amplitude Spectrum in the Frequency Domain

Method of Precise Sensing Channel Positioning for Das Based on the Amplitude Spectrum in the Frequency Domain

What makes modern Britain laugh? How semiotics helped the BBC bridge the Humor Gap

In 2018, BBC Marketing and Audiences approached semiotic agencies with a challenging brief. They wanted to know the following: What makes modern Britain laugh? The BBC’s younger audiences have been steadily drifting to other platforms and broadcasters to satisfy their need for “funny stuff.” Brands that successfully leverage humor really resonate with this new modern mainstream audience, for example, Netflix, BuzzFeed, YouTube, Snapchat, and so on. The BBC, as part of its remit to continue to be a modern evolving brand, wanted to address this trend by understanding what types of comedy content convey a relatable sense of humor and how to best achieve this. The BBC required insight on the following key objectives: Identify key characteristics of content that younger audiences find funny; Explain how this compares with the preferences of the BBC’s older audiences; Estimate how far the BBC brand can stretch in humor content across platform; Assess the need for innovation across BBC platforms to accommodate fresh content. The project involved a multi-methodology approach, the centerpiece of which was a content analysis of 800 data points of consumer generated content derived from WhatsApp diaries. The semiotic analysis, informed by foundational thinking on humor schools and humor psychology, used an innovative hashtagging system to create a nuanced taxonomy of the mostly memes and viral videos with the primary types (e.g., #cringe, #pastiche, #awkwardness, #black humour, #satire, #schadenfreude etc.). The BBC received a comprehensive taxonomy of more than 50 humor types, a digest of levers of engagement for operationalising the humour, and maps for strategic channel positioning. The work has helped the BBC innovate in three core areas: rethinking their use of metadata for tagging comedy content on the iPlayer platform, modifying their tone of voice across all parts of the business, and in commissioning original comedy podcasts for the BBC Sounds app.

WITHDRAWN: Dynamic adaptation in channel estimation under change state scenario

User mobility is a critical concern in wireless communication. During user mobility the channels are Non-linearly vary with time. The non linear variation generates a highly dynamic interference model which leads to considerable processing delay in channel estimation. Filters used in the estimation process were either tuned for a reference frequency band or for a reference signal. However, the estimators face an issue of convergence delay when the interference is non-linear in nature. The existing approaches of estimation were developed with performance enhancement by adaptively controlling the weight factors for input in reference to output and reference value. However, the existing approaches perform the estimation with the assumption of user mobility as interference dynamic. No channel characteristic and positioning of user mobility is been considered. To address the issue, this paper present a new method for estimation constraint based on user positional movement from a reference link with channel characteristic consideration.

Millimeter-Wave Based Localization Using a Two-Stage Channel Estimation Relying on Few-Bit ADCs

Benefiting from the high resolution in beamspace, millimeter wave (mmwave) communication has been regarded as a high-accuracy localization solution, where the location information is embedded in the channel via angle and time delay, for example. In this paper, to locate a user equipment (UE) and scatterers, we present the localization model in mmwave communications as a compressed sensing assisted channel estimation problem, which is solved using a proposed two-stage channel estimation based localization scheme. During the first stage, a sparse Bayesian learning (SBL) algorithm is operated to attain a coarse estimation. Then during the second stage, a multi-stage grid refinement assisted fine estimation is achieved by a distributed compressed sensing simultaneous orthogonal matching pursuit (DCS-SOMP) algorithm. Moreover, in our approach, the few-bit analog to digital converters (ADCs) are utilized by the receiver of UE so as to attain a good trade-off among performance, complexity and energy-efficiency. Finally, the performance of channel estimation and positioning is comprehensively investigated and compared. It can be shown that our proposed two-stage approach is capable of achieving centimeter-level accuracy with the required number of quantization bits of ADCs less than four.

About a Membrane with Microfluidic Porous-Wall Channels of Cylindrical Shape for Droplet Formation.

A low-energy emulsification process is hollow-fiber emulsification. In this process, the lumen diameter of the membrane mostly determines the droplet size. To gain smaller droplets, approaches for downsizing the inner diameter of membranes have to be carried out. In this work, we describe a new method for the fabrication of parallel microfluidic porous-wall channels of a homogeneous cylindrical shape with lumen diameters down to 7 μm. Parallel and symmetric porous-wall channels are induced into polyvinylidene fluoride membranes during the casting process. The technique comprises liquid-induced phase separation and phase-separation micromolding using thin glass and carbon fibers as molds and an in-house designed tool to position the fibers. The channel positioning and alignment are verified within this work. We show and investigate the droplet formation in these porous-wall channels via hollow-fiber emulsification. The formed droplets are very small in diameter and size distribution. The droplet formation at varying flow rates and channel diameters is examined in detail. Moreover, an area of sufficient operating conditions is given using Weber and capillary numbers. As a numbering-up approach, we show the simultaneous formation of spherical droplets in two parallel channels. With the proposed membrane fabrication using micromolding, we push the downscaling approach of hollow-fiber emulsification to lower micron ranges of the channel diameter. With these small channels, droplets with a diameter down to 25 μm were produced, which are more attractive for most applications.

Wigner distribution function and alienation coefficient‐based transmission line protection scheme

This study presents an algorithm for detection, classification, and location of transmission line faults. A fault index based on features extracted from current signals using the alienation coefficient and Wigner distribution function has been proposed for the detection and classification of faults. Double line and double line to ground faults have been classified from each other using ground fault index based on negative sequence current. Statistical relations are proposed for the estimation of fault location using peak values of the proposed fault index. The results of different case studies established the effectiveness of the algorithm. The algorithm is found to be effective for providing protection to transmission line against various faults. This is achieved using current signals recorded on one terminal of the line. This makes the protection scheme less complex, fast and more economic due to the elimination of the requirement of communication channel and global positioning system synchronisation. The proposed protection scheme is also validated on a real-time network of transmission utility. The effectiveness of the algorithm is established by comparing performance with reported algorithms.

Partisan Media and Fiscal Policy Choices: Evidence from U.S. Cable News Channels

Partisan cable news broadcasts have a causal effect on the size and composition of budgets in U.S. localities. Utilizing channel positioning as an instrument for viewership, we show that exposure to the conservative Fox News Channel shrinks local government budgets, while liberal MSNBC enlarges them. Revenue changes are driven by shifts in property taxes, a key tool for local redistributive policy. Expenditure changes are driven by public hospital expenditures, an important discretionary public good provided by local governments. We also find evidence that Fox News exposure increased privatization (while MSNBC decreased it). An analysis of mechanisms suggests that the results are driven by changes in voter preferences, but not by changes in partisan control of city governments.

LRRC52 regulates BK channel function and localization in mouse cochlear inner hair cells

The perception of sound relies on sensory hair cells in the cochlea that convert the mechanical energy of sound into release of glutamate onto postsynaptic auditory nerve fibers. The hair cell receptor potential regulates the strength of synaptic transmission and is shaped by a variety of voltage-dependent conductances. Among these conductances, the Ca2+- and voltage-activated large conductance Ca2+-activated K+ channel (BK) current is prominent, and in mammalian inner hair cells (IHCs) displays unusual properties. First, BK currents activate at unprecedentedly negative membrane potentials (-60 mV) even in the absence of intracellular Ca2+ elevations. Second, BK channels are positioned in clusters away from the voltage-dependent Ca2+ channels that mediate glutamate release from IHCs. Here, we test the contributions of two recently identified leucine-rich-repeat-containing (LRRC) regulatory γ subunits, LRRC26 and LRRC52, to BK channel function and localization in mouse IHCs. Whereas BK currents and channel localization were unaltered in IHCs from Lrrc26 knockout (KO) mice, BK current activation was shifted more than +200 mV in IHCs from Lrrc52 KO mice. Furthermore, the absence of LRRC52 disrupted BK channel localization in the IHCs. Given that heterologous coexpression of LRRC52 with BK α subunits shifts BK current gating about -90 mV, to account for the profound change in BK activation range caused by removal of LRRC52, we suggest that additional factors may help define the IHC BK gating range. LRRC52, through stabilization of a macromolecular complex, may help retain some other components essential both for activation of BK currents at negative membrane potentials and for appropriate BK channel positioning.

Audience Preferences and Popular Program Patterns on News Channels in Karachi

This research aims to study the factors that influence the viewership of leading Pakistani News Channels including Dunya, Samaa, Express, Geo and ARY. It examines the impact of content, presentation style, channel positioning and anchors, alongside overall news viewing patterns, on the public image of the identified news channels and their viewership with focus on Express News. Following a qualitative research approach, a representative sample of 51 news viewers is identified and interviewed, with a proportionate weight to geographical areas and socio-economic classification of the audience, based on recent Census and People’s meter, an audience measurement tool. The respondents are investigated through a comprehensive questionnaire, comprised both closed and open-ended questions. This study focuses on three categories of viewers including Express News Viewers, Express-News Lapsers and Competitive Channels Viewers. One-on-one interviews reflect the mindset and viewing patterns of news channels’ audience. It is also instrumental to highlight the factors that hinder Express-News ratings against its competing channels. Findings of the study indicate that the programme content, presentation style, and cable positioning of news channels significantly influence its viewership that results in the quantum of recall for Express-News, and how its viewership and ratings are presumably affected by the very factors.

A Numerical Investigation of Through-Tool Coolant Wetting Behaviour in Twist-Drilling

Supplying coolant through internal coolant channels is a common method of transporting large thermal loads away from the tool in twist-drill machining to increase tool life, aid chip evacuation and avoid catastrophic tool failure. In this work a finite element-based numerical model of the machining process is loosely coupled with a finite volumebased numerical method for predicting the distribution of coolant inside the borehole. These methods are employed to study the effect of channel position on cutting geometry lubrication and uses response surface models to show that all designs do not fully flood the borehole and that not all areas of the tool geometry are lubricated with coolant. Visual analysis of results show that coolant, for all designs, primarily lubricates the area between the cutting edge and the coolant hole exit, however depending on application requirements coolant channel positioning can be used to modify coolant supply to the axial rake, for chip evacuation or to the cutting edge for heat removal.

Defining the Costs of Reusable Flexible Ureteroscope Reprocessing Using Time-Driven Activity-Based Costing.

Careful decontamination and sterilization of reusable flexible ureteroscopes used in ureterorenoscopy cases prevent the spread of infectious pathogens to patients and technicians. However, inefficient reprocessing and unavailability of ureteroscopes sent out for repair can contribute to expensive operating room (OR) delays. Time-driven activity-based costing (TDABC) was applied to describe the time and costs involved in reprocessing. Direct observation and timing were performed for all steps in reprocessing of reusable flexible ureteroscopes following operative procedures. Estimated times needed for each step by which damaged ureteroscopes identified during reprocessing are sent for repair were characterized through interviews with purchasing analyst staff. Process maps were created for reprocessing and repair detailing individual step times and their variances. Cost data for labor and disposables used were applied to calculate per minute and average step costs. Ten ureteroscopes were followed through reprocessing. Process mapping for ureteroscope reprocessing averaged 229.0 ± 74.4 minutes, whereas sending a ureteroscope for repair required an estimated 143 minutes per repair. Most steps demonstrated low variance between timed observations. Ureteroscope drying was the longest and highest variance step at 126.5 ± 55.7 minutes and was highly dependent on manual air flushing through the ureteroscope working channel and ureteroscope positioning in the drying cabinet. Total costs for reprocessing totaled $96.13 per episode, including the cost of labor and disposable items. Utilizing TDABC delineates the full spectrum of costs associated with ureteroscope reprocessing and identifies areas for process improvement to drive value-based care. At our institution, ureteroscope drying was one clearly identified target area. Implementing training in ureteroscope drying technique could save up to 2 hours per reprocessing event, potentially preventing expensive OR delays.

EBI2-mediated bridging channel positioning supports splenic dendritic cell homeostasis and particulate antigen capture

Splenic dendritic cells (DCs) present blood-borne antigens to lymphocytes to promote T cell and antibody responses. The cues involved in positioning DCs in areas of antigen exposure in the spleen are undefined. Here we show that CD4(+) DCs highly express EBI2 and migrate to its oxysterol ligand, 7α,25-OHC. In mice lacking EBI2 or the enzymes needed for generating normal distributions of 7α,25-OHC, CD4(+) DCs are reduced in frequency and the remaining cells fail to situate in marginal zone bridging channels. The CD4(+) DC deficiency can be rescued by LTβR agonism. EBI2-mediated positioning in bridging channels promotes DC encounter with blood-borne particulate antigen. Upon exposure to antigen, CD4(+) DCs move rapidly to the T-B zone interface and promote induction of helper T cell and antibody responses. These findings establish an essential role for EBI2 in CD4(+) DC positioning and homeostasis and in facilitating capture and presentation of blood-borne particulate antigens. DOI:http://dx.doi.org/10.7554/eLife.00757.001.

한국 해외홍보방송의 편성전략과 채널 포지셔닝 설정

이 연구는 우리나라 해외홍보방송인 아리랑TV(아리랑 World)와 KBS World를 선정하여 편성전략의 특성과 편성에 따른 채널 포지셔닝의 차별성을 살펴보는 것을 목적으로 한다. 분석 결과, 편성전략에서는 아리랑TV가 교양 프로그램위주의 한국 문화콘텐츠를 편성하는, 반면 KBS World는 KBS 1, 2TV의 주요 프로그램을 활용한 드라마와 연예 등 오락프로그램의 편성비율이 높았다. 아리랑 TV의 경우 다큐멘터리, 관광정보, 생활정보 등 문화 콘텐츠 중심의 국가홍보에 충실한 편성을 하고 있다. KBS World는 드라마와 <뮤직 뱅크>와 같은 K-pop을 편성하여 한류 확산의 중심 채널로서의 역할을 하고 있다. 이같은 편성전략의 특성에 따라 아리랑TV는 한국문화를 전파하는 외교채널로서 포지셔닝을 하고 있고, KBS World는 한류 확산의 엔터테인먼트 채널로 자리를 잡고 있다. 그러나 두 채널의 편성 전략이 한국 문화 소개 및 한류 확산을 목표로 하고 있고, 타깃이 해외 동포나 외국인을 대상으로 한다는 점에서 중복투자에 따른 비효율성 문제가 제기되고 있다. The research is centered towards analyzing the differentiation of the characteristics and organization of programming strategy and channel positioning by selecting Korean International Public Relations Broadcasting Stations Arirang TV and KBS World. According to the results, Arirang TV positions Korean culture content-implied educational programs as their strategy while KBS World places the main programs of KBS1, 2TV with many entertainment programs such as dramas and entertainment shows. Arirang TV's programming strategy is well-fulfilling the purpose of promoting Korea's culture contents by organizing their programming with documentaries, tourist information, and daily living information. On the other hand, KBS World works as the agent of the spread of the Korean Wave by filling their program with dramas and K-pop programs such as <Music Bank>. Due to the difference in programming strategy of these two broadcasting stations, Arirang TV has positioned itself as a diplomatic channel to spread Korean culture and KBS World a channel representing the Korean Wave. However, there are problems of inefficiency due to recurrent investments because of the fact that both broadcasting stations' programming strategy is to promote Korean culture and spread the Korean Wave by aiming similar targets such as foreigners or overseas Koreans.

Consumers' Channel Choice and Channel Positioning in Multichannel Environment

Consumers' Channel Choice and Channel Positioning in Multichannel Environment

CENTER CHANNEL POSITIONING APPARATUS

A center channel positioning apparatus is provided, which does not cause strange feeling in sound quality even at a position apart from an original listener position. A sound signal processing unit ( 40 ) changes a phase of at least one of a left sound signal for center channel positioning (CL) and a right sound signal for center channel positioning (CR), based on a processing coefficient, and causes a left speaker ( 46 ) and a right speaker ( 52 ) to output sound based on a center channel sound signal (C). The processing coefficient is calculated based on the difference in level between both ears in the case where the left sound signal for center channel positioning (CL) for the left speaker ( 46 ), and the right sound signal for center channel positioning (CR) for the right speaker ( 52 ) are reproduced simultaneously.