Auxiliary Channels Research Articles

Rekayasa Sistem Tata Air Lokasi Transmigrasi Palingkau Asri Lahan Usaha Satu SP-2 Di Wilayah Kabupaten Kapuas Propinsi Kalimantan Tengah

Agriculture land in the transmigration location of Palingkau Asri is one of the development locations for tidal land development in Kalimantan. In its development this location has been divided into three settlement areas (SP), one of them is the SP-2. The focus of this research is Lahan Usaha Satu at SP-2. There are already irrigation networks consisting of irrigation channels (a simple drainage system) in the form of primary pilot channels, primary auxiliary channels, and tertiary channels. The main problems of this location include the excess of water that occurs in rainy seasons and a water system that does not function properly. To overcome these problems research was carried out in the following steps. Firstly, primary and secondary data were taken. Secondly, the water system optimization was examined using a mathematical model that was solved by using the HEC-RAS software package. Lastly, the problem of the excess water (floods) was solved by determining a dike height for a period of 25 years and optimizing the water system with water management structures such as watergates. The results indicated that the existing water management system still can handle the excess of water although the tertiary channels were overflowed (channel of T2, T4, T6, T12) especially at T6, where the overflow reached a maximum value of 1.1 m. The simulation with HEC-RAS

Distributed quantum metrology with a single squeezed-vacuum source

We propose an interferometric scheme for the estimation of a linear combination with non-negative weights of an arbitrary number $M>1$ of unknown phase delays, distributed across an $M$-channel linear optical network, with Heisenberg-limited sensitivity. This is achieved without the need of any sources of photon-number or entangled states, photon-number resolving detectors or auxiliary interferometric channels. Indeed, the proposed protocol remarkably relys upon a single squeezed state source, an antisqueezing operation at the interferometer output, and on-off photodetectors.

Signaling effects and the role of culture: movies in international auxiliary channels

Purpose Given the high uncertainty in the quality perception of experiential products, manufacturers use signals to influence consumers’ decisions. In the movie industry, literature shows that performance of the main channel (e.g. cinema) strongly influences the performance of auxiliary channels (e.g. DVDs). The success of a movie in the home country is also to be resonated by its good performance in host countries. However, the cultural contingency of these success-breeds-success (SBS) effects has not been examined. This paper aims to test the influence of cultural values on the SBS effects across channels and countries. Design/methodology/approach Borrowing concepts from the signaling literature and analyzing DVD sales data from six international markets using a multilevel mixed-effects model, the study finds that culture plays a significant role to influence both SBS effects. Findings In countries with low power distance, short-term orientation and high indulgence, consumers who purchase from auxiliary channels are more likely to be influenced by the box office performance of movies. Meanwhile, cultural distance between the home and host nations significantly decreases the cross-national SBS effect. Research limitations/implications The findings are likely to be generalized to online auxiliary channels of movies, but empirical testing is required to ensure that no major adaptation is required in the process. Future research can also extend the framework of this paper to include more countries into the analysis and investigate cultural variables beyond Hofstede’s dimensions. Practical implications This paper suggests that the SBS effects may vary across nations. When managers plan for the sequential distributions of experiential products, the cultural values of target markets should be considered to decrease the uncertainty in sales prediction. Originality/value This paper contributes to the existing literature by investigating the international auxiliary channels of movies and incorporating cultural values into the framework of sequential distributions. To the best of the authors’ knowledge, this study is the first to test the links between the main and auxiliary channels from an international marketing perspective.

DATA AUGMENTATION APPROACHES FOR SATELLITE IMAGE SUPER-RESOLUTION

Abstract. Data augmentation is a well known technique that is frequently used in machine learning tasks to increase the number of training instances and hence decrease model over-fitting. In this paper we propose a data augmentation technique that can further boost the performance of satellite image super resolution tasks. A super-resolution convolutional neural network (SRCNN) was adopted as a state-of-the-art deep learning model to test the proposed data augmentation technique. Different augmentation techniques were studied to investigate their relative importance and accuracy gains. We categorized the augmentation methods into instance based and channel based augmentation methods. The former refers to the standard approach of creating new data instances through applying image transformations to the original images such as adding artificial noise, rotations and translations to training samples, while in the latter we fuse auxiliary channels (or custom bands) with each training instance, which helps the model learn useful representations. Fusing auxiliary derived channels to a satellite image RGB combination can be seen as a spectral-spatial fusion process as we explain later. Several experiments were carried out to evaluate the efficacy of the proposed fusion-based augmentation method compared with traditional data augmentation techniques such as rotation, flip and noisy training inputs. The reconstruction quality of the high resolution output was quantitatively evaluated using Peak-Signal-To-Noise-Ratio (PSNR) and qualitatively through visualisation of test samples before and after super-resolving.

Blip glitches in Advanced LIGO data

Blip glitches are short noise transients present in data from ground-based gravitational-wave observatories. These glitches resemble the gravitational-wave signature of massive binary black hole mergers. Hence, the sensitivity of transient gravitational-wave searches to such high-mass systems and other potential short duration sources is degraded by the presence of blip glitches. The origin and rate of occurrence of this type of glitch have been largely unknown. In this paper we explore the population of blip glitches in Advanced LIGO during its first and second observing runs. On average, we find that Advanced LIGO data contains approximately two blip glitches per hour of data. We identify four subsets of blip glitches correlated with detector auxiliary or environmental sensor channels, however the physical causes of the majority of blips remain unclear.

Convolutional Neural Network-Based Moving Ground Target Classification Using Raw Seismic Waveforms as Input

Seismic vibration signatures are strong criteria to recognize moving ground targets in unattended ground sensor (UGS) systems. However, it is a challenging task because of the complexity of seismic waves and their high dependency on the underlying geology. In order to approach this problem, this paper proposes a novel method called “VibCNN” based on convolutional neural networks (CNNs). Instead of preprocessing signals to extract features, the proposed model takes raw waveforms as input. Another characteristic of the model is that it can handle very short input, which only contains 1024 sample points. The experimental results show that the model yields performance much better than benchmarks and generalizes quite well across different geological types. To further improve the performance of VibCNN, we introduce two auxiliary input channels based on seismic signals and add each auxiliary channel to the input layer of VibCNN separately. Furthermore, we explore different fusion rules of the auxiliary channels at three levels: sample level, feature level, and decision level. The best result achieves relative improvement of 2.05%. In addition, data augmentation for seismic data has not been deeply investigated yet. Thus, we conduce a data augmentation experiment to explore the influence of different augmentation techniques on the performance of the model. The appropriate augmentation improves the accuracy of the model from 93.44% to 95.20%.

Chiral BINOL-Based Covalent Organic Frameworks for Enantioselective Sensing.

Covalent organic frameworks (COFs) have emerged as a novel platform for material design and functional explorations, but it remains a challenge to synthetically functionalize targeted structures for task-specific applications. Optically pure 1,1'-bi-2-naphthol (BINOL) is one of the most important sources of chirality for organic synthesis and materials science, but it has not yet been used in construction of COFs for enantioselective processes. Here, by elaborately designing and choosing an enantiopure BINOL-based linear dialdehyde and a tris(4-aminophenyl)benzene derivative or tetrakis(4-aminophenyl)ethene as building blocks, two imine-linked chiral fluorescent COFs with a 2D layered hexagonal or tetragonal structure are prepared. The COF containing flexible tetraphenylethylene units can be readily exfoliated into ultrathin 2D nanosheets and electrospun to make free-standing nanofiber membrane. In both the solution and membrane systems, the fluorescence of COF nanosheets can be effectively quenched by chiral odor vapors via supramolecular interactions with the immobilized BINOL moieties, leading to remarkable chiral vapor sensors. Compared to the BINOL-based homogeneous and membrane systems, the COF nanosheets exhibited greatly enhanced sensitivity and enantioselectivity owing to the confinement effect and the conformational rigidity of the sensing BINOL groups in the framework. The ability to place such a useful BINOL chiral auxiliary inside open channels of COFs capable of amplifying chiral discrimination of the analytes represents a major step toward the rational synthesis of porous molecular materials for more chirality applications.

Towards identifying and preventing behavioral side channel attack on recording attack resilient unaided authentication services

Side channel attacks, based on the human behavior, have not received much attention in the domain of recording attack resilient unaided authentication services (RARUAS) that purely rely on human visual perception but not on hidden auxiliary channels. In this paper, for the first time, we have made an extensive analysis to show - how human behavior during the login can weaken the claimed security standard of RARUAS. We identify this threat as behavioral side channel attack. To make situation more alarming, our investigation revealed that the identified threat model is capable of reducing the claimed session resiliency of any RARUAS by a significant extent. For dealing with this threat model, the latter part of our proposal introduces a novel defense strategy that reduces attackers’ efficiency and improves the session resiliency. The subsequent study indicates that by nature of its design, the proposed defense strategy does not make any significant impact on the usability standard. To validate our claims, we have made a thorough experimental study to show that the proposed defense strategy is truly deployable in practice for improving the situation against the behavioral side channel attack.

Split-Type Input-Reflectionless Multiband Filters

Split-type multiband bandpass filters (BPFs) and bandstop filters (BSFs) with input-reflectionless capabilities are reported in this letter. In the multiband BPF case, they consist of a duplexing network with a split-type multiband BPF channel—main channel—and its complementary resistively terminated multiband BSF channel—auxiliary channel—that absorbs the input-signal energy that is not transmitted by the overall filter. The multiband BSF counterpart is obtained from the latter by interchanging the roles of the main and auxiliary channels. The operational foundations, theoretical design rules, and synthesis examples of the devised split-type input-reflectionless multiband filters under a coupling-matrix-based formulation are described. Furthermore, for practical validation purposes, two microstrip prototypes corresponding to 3.85-/4.55-GHz second-order dual-band BPF and BSF circuits are constructed and measured.

Identifying correlations between LIGO’s astronomical range and auxiliary sensors using lasso regression

The range to which the Laser Interferometer Gravitational-Wave Observatory (LIGO) can observe astrophysical systems varies over time, limited by noise in the instruments and their environments. Identifying and removing the sources of noise that limit LIGO’s range enables higher signal-to-noise observations and increases the number of observations. The LIGO observatories are continuously monitored by hundreds of thousands of auxiliary channels that may contain information about these noise sources. This paper describes an algorithm that uses linear regression, namely lasso (least absolute shrinkage and selection operator) regression, to analyze all of these channels and identify a small subset of them that can be used to reconstruct variations in LIGO’s astrophysical range. Exemplary results of the application of this method to three different periods of LIGO Livingston data are presented, along with computational performance and current limitations.

Fault detection of the connection of lithium-ion power batteries in series for electric vehicles based on statistical analysis

Inter-cell virtual connection is likely to occur in the process of electric vehicles driving, which could cause fire or explosion accident. This paper presents a connecting fault detection method of lithium-ion power batteries in series. The cross-voltage test is adopted to distinguish contact resistance increases and internal resistance increases fault. The battery voltage and negative surface temperature are collected by battery test system and auxiliary channels equipment. The experimental battery based on first-order resistance and capacitance (RC) equivalent circuit and MATLAB/Simulink platform is simulated. The mean square error which indicates the difference between experiment and simulation is employed to describe voltage state of the cell. If the abnormal voltage exists, it is concluded that a fault occurs through analyzing the voltage abnormal coefficients based on modified Z-score, which is considered as a second-degree fault. The temperature rise rate is regarded as a secondary parameter to determine whether the second-degree fault deteriorates into a first-degree fault. According to different levels of failure, battery management system reminds users to take appropriate measures in practice. This work can provide an effective method of detecting lithium-ion power batteries connecting failure in series.

Improved Lower Bounds on Mutual Information Accounting for Nonlinear Signal–Noise Interaction

In fiber-optic communications, evaluation of mutual information (MI) is still an open issue due to the unavailability of an exact and mathematically tractable channel model. Traditionally, lower bounds on MI are computed by approximating the (original) channel with an auxiliary forward channel. In this paper, lower bounds are computed using an auxiliary backward channel, which has not been previously considered in the context of fiber-optic communications. Distributions obtained through two variations of the stochastic digital backpropagation (SDBP) algorithm are used as auxiliary backward channels and these bounds are compared with bounds obtained through the conventional digital backpropagation (DBP). Through simulations, higher information rates were achieved with SDBP, {which can be explained by the ability of SDBP to account for nonlinear signal--noise interactions

Flow boiling of HFE-7100 in silicon microchannels integrated with multiple micro-nozzles and reentry micro-cavities

Flow boiling of dielectric fluids in microchannels is one of the most desirable cooling solutions for high power electronics. However, the flow boiling of dielectric fluids is hindered by their unfavorable thermophysical properties. Specifically, without precooling dielectric fluids, it is challenging to promote critical heat flux (CHF) due to its high vapor density, low surface tension and the resulted superior wettability. In this study, each side wall of a five-parallel silicon microchannel array was structured with an array of microscale reentry cavities and four micronozzles bypassed by an auxiliary channel. The present microchannel configuration aims to significantly enhance CHF of HFE-7100 flow boiling by improving global liquid supply using auxiliary channels and micrononozzles as well as by sustaining liquid film using capillarity induced by reentry cavity array. Equally important, these structures can promote nucleate boiling at low heat flux, generate intense mixing, and promote thin film evaporation at high heat flux, resulting in high flow boiling heat transfer rate. Flow boiling of HFE-7100 in the present microchannel configuration is characterized with mass flux ranging from 231 kg/m2 s to 1155 kg/m2 s. The effective two-phase heat transfer coefficients (HTCs) are ranging from 6 kW/m2 K to 117 kW/m2 K. Compared to the four-nozzle plain-wall microchannels, for example, the effective HTC and CHF can be substantially enhanced up to 208% and 37%, respectively, without escalating pressure drop at a mass flux of 462 kg/m2 s. Compared to plain microchannels with inlet restrictors, CHF is considerably enhanced up to 70% with a reduction of pressure drop ∼82% at a mass flux of 1155 kg/m2 s. Significantly reduced pressure drop is achieved by integrating bypass and the enhanced confined bubble removal. A peak CHF value of 216 W/cm2 is achieved at mass flux of 2772 kg/m2 s in the present microchannel configuration with inlet temperature at room temperature.

Smeared spectrum jamming suppression based on time unit analysis and polarization cancellation

By analyzing the time structure after pulse compression, an electronic counter-countermeasure (ECCM) combining time unit analysis and polarization cancellation is proposed in this paper to counter smeared spectrum (SMSP) jamming, which is an effective jamming type to linear frequency modulation (LFM) signals. The stretch processing to receive signals in main and auxiliary channels is firstly done and the time structure differences of pulse compression results are analyzed. Based on the time structure differences, the main-to-auxiliary ratio is defined, and the characteristics of this function in different time units are analyzed. According to the statistical parameter of modulus and phase ratio in different time units, the jamming suppression factor is computed by searching the jamming-only time unit. The influences of background noise and polarization purity are analyzed finally. Some computer simulation results are given to prove the effectiveness of the proposed method.

Enhanced flow boiling in microchannels using auxiliary channels and multiple micronozzles (I): Characterizations of flow boiling heat transfer

Flow boiling in parallel microchannels can be dramatically enhanced through inducing self-excited and self-sustained high frequency two-phase oscillations as demonstrated in our previous studies using a two-nozzle microchannel configuration. Two-phase mixing induced by the rapid bubble collapse is shown to be the major enhancement mechanism. However, in the two-nozzle configuration microchannels, the mixing effect is limited to the downstream of the microchannels, meaning that only half length of the entire microchannel is functionalized as designated. In this study, a four-nozzle microchannel configuration is developed with an aim at extending the highly desirable mixing effect to the entire channel. Flow boiling in the four-nozzle configuration microchannels is experimentally studied with deionized water and the mass flux ranging from 120kg/m2 s to 600kg/m2 s. The onset of nucleate boiling temperature is considerably reduced by ∼14% because of more nucleation sites created by the multiple nozzles. Equally important, the improved microchannel configuration successfully extends the mixing to the entire channel as validated by the enhanced heat transfer rate and visualization study. Compared to the previous two-nozzle configuration, the overall heat transfer coefficient (HTC) is significantly improved primarily owing to the enhanced nucleate boiling. For example, the peak overall HTC of 262kW/m2 K is achieved at a mass flux of 150kg/m2 s, accounting for ∼83.7% enhancement. Additionally, the peak effective HTC reaches 97.6kW/m2 K, accounting for ∼67% enhancement.

Enhanced flow boiling in microchannels using auxiliary channels and multiple micronozzles (II): Enhanced CHF and reduced pressure drop

Enhancing critical heat flux (CHF) of flow boiling without escalating pressure drop is highly desirable in thermal management of high power-density electronic devices. Usually, an improved CHF can be achieved by restricting flow or at a higher mass velocity, leading to a higher pressure drop. In this study, compared to the two-nozzle microchannel configuration, the improved microchannel configuration as detailed in the Part (I) of this study can enhance CHF without sacrificing pressure drop. In this part, CHF is experimentally evaluated together with the pressure drop with mass flux ranging from 120kg/m2s to 600kg/m2s. Compared to the two-nozzle configuration, our study shows that CHF can be enhanced up to 32% with a ∼53% reduction of pressure drop at a mass flux of 325kg/m2s. The bubble collapse-removal process is significantly improved because more micronozzles are integrated. The enhanced pumping effect, which is created by rapid bubble collapse processes in the entire main channels, enables a more sustainable liquid supply and hence delays the CHF conditions. Moreover, two-phase flow in terms of pressure drop fluctuations is more stable owing to the effective management of bubble confinement in the entire channel.

Interactive reconstruction of Monte Carlo image sequences using a recurrent denoising autoencoder

We describe a machine learning technique for reconstructing image sequences rendered using Monte Carlo methods. Our primary focus is on reconstruction of global illumination with extremely low sampling budgets at interactive rates. Motivated by recent advances in image restoration with deep convolutional networks, we propose a variant of these networks better suited to the class of noise present in Monte Carlo rendering. We allow for much larger pixel neighborhoods to be taken into account, while also improving execution speed by an order of magnitude. Our primary contribution is the addition of recurrent connections to the network in order to drastically improve temporal stability for sequences of sparsely sampled input images. Our method also has the desirable property of automatically modeling relationships based on auxiliary per-pixel input channels, such as depth and normals. We show significantly higher quality results compared to existing methods that run at comparable speeds, and furthermore argue a clear path for making our method run at realtime rates in the near future.

Some Remarks on Classical and Classical-Quantum Sphere Packing Bounds: Rényi vs. Kullback–Leibler

We review the use of binary hypothesis testing for the derivation of the sphere packing bound in channel coding, pointing out a key difference between the classical and the classical-quantum setting. In the first case, two ways of using the binary hypothesis testing are known, which lead to the same bound written in different analytical expressions. The first method historically compares output distributions induced by the codewords with an auxiliary fixed output distribution, and naturally leads to an expression using the Renyi divergence. The second method compares the given channel with an auxiliary one and leads to an expression using the Kullback–Leibler divergence. In the classical-quantum case, due to a fundamental difference in the quantum binary hypothesis testing, these two approaches lead to two different bounds, the first being the “right” one. We discuss the details of this phenomenon, which suggests the question of whether auxiliary channels are used in the optimal way in the second approach and whether recent results on the exact strong-converse exponent in classical-quantum channel coding might play a role in the considered problem.

Enhanced flow boiling in microchannels through integrating multiple micro-nozzles and reentry microcavities

In a microchannel system, a higher mass velocity can lead to enhanced flow boiling performances, but at a cost of two-phase pressure drop. It is highly desirable to achieve a high heat transfer rate and critical heat flux (CHF) exceeding 1 kW/cm2 without elevating the pressure drop, particularly, at a reduced mass velocity. In this study, we developed a microchannel configuration that enables more efficient utilization of the coolant through integrating multiple microscale nozzles connected to auxiliary channels as well as microscale reentry cavities on sidewalls of main microchannels. We achieved a CHF of 1016 W/cm2 with a 50% less mass velocity, i.e., 680 kg/m2s, compared to the two-nozzle configuration developed in our previous studies. Two primary enhancement mechanisms are: (a) the enhanced global liquid supply by four evenly distributed micronozzles, particularly near the outlet region and (b) the effective management of local dryout by the capillary flow-induced sustainable thin liquid film resulting from an array of microscale cavities. A significantly improved heat transfer coefficient of 131 kW/m2 K at a mass velocity of 680 kg/m2s is attributed to the enhanced nucleate boiling, the established capillary/thin film evaporation, and the induced advection from the present microchannel configuration. All these significant enhancements have been achieved with a ∼55% lower two-phase pressure drop.

Constant Compositions in the Sphere Packing Bound for Classical-Quantum Channels

The sphere packing bound, in the form given by Shannon, Gallager, and Berlekamp, was recently extended to classical-quantum channels, and it was shown that this creates a natural setting for combining probabilistic approaches with some combinatorial ones such as the Lovász theta function. In this paper, we extend the study to the case of constant-composition codes. We first extend the sphere packing bound for classical-quantum channels to this case, and we then show that the obtained result is related to a variation of the Lovász theta function studied by Marton. We then propose a further extension to the case of varying channels and codewords with a constant conditional composition given a particular sequence. This extension is finally applied to auxiliary channels to deduce a bound, which is useful in the low rate region and which can be interpreted as an extension of the Elias bound.