Simple Series Research Articles

Roles of kink on the thermal transport in single polyethylene chains

The trans-gauche state transformation commonly exists in polymers. However, the fundamental understanding of the roles of kink (gauche state) on the thermal energy transport in polymer chains is rather limited. From atomic simulations, we show that kinks greatly scatter phonons in single polyethylene chains, and even a single kink can reflect more than half of the phonons. Further studies show that kinks not only add extra thermal resistance to the chain but also break the whole chain into small segments and each with reduced thermal conductivity. A simple series thermal resistance model is proposed to estimate the effective thermal conductivity of single polymer chains with multiple kinks.

Hey mister Tambourine Dove, sing a song for me: simple but individually specific songs of Turtur tympanistria from Cameroon

BackgroundThe broadcast song of the Tambourine Dove (Turtur tympanistria) is a repetitive coo series produced in a very stereotyped way. The song is similar to those of the other species within the Turtur genus and likely reflects the adaptation to long distance signalling in tropical habitats. There is no study assessing individual variation of the Tambourine Dove song or for the possibility of identity coding through song features.MethodsWe obtained recordings of 578 songs from 41 males within a population inhabiting montane forest in Cameroon between 2008 and 2018. Additionally, we analysed also recordings from automatic recorders working for a longer time during the year. Songs were analysed to get basic information about within- and between-individual spectro-temporal variation. Potential of identity coding and discriminant analyses were used to investigate if and how these songs may convey information about male identity.ResultsThe song of the Tambourine Dove is a very simple series of short, unmodulated whistles with low frequency and a narrow bandwidth. Measurements of single song features indicated either none or a weak potential for identity coding. The overall variation in song frequency characteristics was very low. However, the number of notes forming a song (and consequently the duration) had a similar variability both within- and between individuals. When using multiple song measurements discrimination analysis revealed a high potential for identity coding although it seems that the temporal pattern of the beginning of a song carries the most information about sender identity. The production of initial notes within a song has very precise, individually specific timing allowing for up to 96.7% correct recognitions of songs. Comparison of recordings from the same points but separated in time by over a month indicates that song parameters are individually stable over longer period.ConclusionsDespite having highly stereotyped and simple songs, Tambourine Dove males produce individually specific signals which have a great potential for recognition by rivals or mates. All Turtur doves have similar yet unique songs that are different to the songs of other pigeon species. This genus seems to be a perfect model for studying the trade-off between coding for species identity and individual identity in a non-learning bird species. The described method of individual recognition allows for nonintrusive population monitoring.

A new and simple split series strings approach for adding bypass diodes in shingled cells modules to reduce shading loss

Overlapping solar cells in shingled cells modules create series strings, making it difficult to connect bypass diodes across the modules. A new, simple split strings approach is proposed in this paper, where copper foil tapes are attached to the back of the cells. A module can be bridged by two bypass diodes with this approach, and the effects of shading area and orientation on the electrical performance of the module were investigated. The current-voltage and power-voltage curves of the module were measured in three different shading cases. It was found that the output performance declines critically as the shading area increases along the vertical direction. Moreover, the obtained results were compared with results from shaded modules without split strings in order to justify the benefits of the new split strings approach for reducing shading loss.

Sleep preferentially enhances memory for a cognitive strategy but not the implicit motor skills used to acquire it

Sleep is known to be beneficial to the strengthening of two distinct forms of procedural memory: memory for novel, cognitively simple series of motor movements, and memory for novel, cognitively complex strategies required to solve problems. However, these two types of memory are intertwined, since learning a new cognitive procedural strategy occurs through practice, and thereby also requires the execution of a series of simple motor movements. As a result, it is unclear whether the benefit of sleep results from the enhancement of the cognitive strategy, or the motor skills required to execute the solution. To disentangle the role of sleep in these aspects of procedural memory, we employed two tasks: (1) the Tower of Hanoi (ToH), and, (2) a modified version of the ToH, akin to an implicit Motor Sequence Learning (MSL) task. The MSL task involved the identical series of motor movements as the ToH, but without access to the information necessary to execute the task according to the underlying cognitive procedural strategy. Participants (n = 28) were trained on the 3-disk ToH, then retested on 5-disk versions of both ToH and MSL tasks. Half (n = 15) were trained and immediately tested at 8 PM and retested at 8 AM after a night of sleep. They were retested again at 8 PM after a day of wake (PM-AM-PM condition). The other half (n = 13) were trained and immediately tested at 8 AM, retested at 8 PM after a day of wake, and retested again at 8 AM after a night of sleep (AM-PM-AM condition). ToH performance only improved following a period of sleep. There was no benefit of sleep to implicit MSL. Our results show that sleep, but not wake, allowed individuals to extrapolate what was learned on a simpler 3-disk version of the task to the larger 5-disk problem, which included new elements to which they had not yet been exposed. Here, we isolate the specific role sleep plays for cognitive procedural memory: sleep benefits the cognitive strategy, rather than strengthening implicitly acquired motor sequences required to learn and execute the underlying strategy itself.

Impact of contact and channel resistance on the frequency-dependent capacitance and conductance of pseudo-MOSFET

This paper discusses the impact of both contact and channel resistance on capacitance and conductance characteristics measured with pseudo-MOSFET method by analyzing the impedance and admittance in frequency domain. We clarify the mechanisms affecting the ac response of pseudo-MOSFET structure for SOI wafer with thin SOI film by using simple series and parallel circuits composed of resistance and capacitance. Our measurement results show the gate bias range where the influence of the contact resistance becomes dominant in measurements with single and multiple probes. The degradation of the capacitance measured at high frequency is also analyzed by constructing an equivalent circuit, which detach the influence of the contact and channel resistances quantitatively. The necessity to carefully account for the influence of the contact resistance in pseudo-MOS method is clarified.

Closure for the Ornstein-Zernike equation with pressure and free energy consistency.

The Ornstein-Zernike (OZ) integral equation theory is a powerful approach to simple liquids due to its low computational cost and the fact that, when combined with an appropriate closure equation, the theory is thermodynamically complete. However, approximate closures proposed to date exhibit pressure or free energy inconsistencies that produce inaccurate or ambiguous results, limiting the usefulness of the Ornstein-Zernike approach. To address this problem, we combine methods to enforce both pressure and free energy consistency to create a new closure approximation and test it for a single-component Lennard-Jones fluid. The closure is a simple power series in the direct and total correlation functions for which we have derived analytical formulas for the excess Helmholtz free energy and chemical potential. These expressions contain a partial molar volumelike term, similar to excess chemical potential correction terms recently developed. Using our bridge approximation, we have calculated the pressure, Helmholtz free energy, and chemical potential for the Lennard-Jones fluid using the Kirkwood charging, thermodynamic integration techniques, and analytic expressions. These results are compared with those from the hypernetted chain equation and the Verlet-modified closure against Monte Carlo and equations-of-state data for reduced densities of ρ^{*}<1 and temperatures of T^{*}=1.5, 2.74, and 5. Our closure shows consistency among all thermodynamic paths, except for one expression of the Gibbs-Duhem relation, whereas the hypernetted chain equation and the Verlet-modified closure exhibit consistency between only a few relations. Accuracy of the closure is comparable to the Verlet-modified closure and a significant improvement to results obtained from the hypernetted chain equation.

Measurement of productivity changes for general network production systems with stochastic data

Performance evaluation of network production systems has been widely studied in recent Data Envelopment Analysis (DEA) literature where internal relations of sub-units are taken into consideration. Most of prior work assumes network systems to have simple series or parallel structures. Complexities of some practical production processes require development of DEA models for their effective analysis. However; input, intermediate products and/or output data are often stochastic and linked to exogenous random variables in most applications. The current study extends Malmquist Productivity Index (MPI) for investigating productivity changes of general network production units with stochastic data in a DEA framework. The proposed stochastic performance analysis models are then transformed into deterministic equivalent non-linear forms so they could be simplified to deterministic programming with quadratic constraints. Numerical examples including an application to productivity evaluation of branches of a university system are presented to illustrate the applicability of the proposed framework.

Comparison of daily flows simulated for the year 2060 on the Kaczawa River for various scenarios of climate change by simple time series analysis

In this paper a time series analysis for daily flow simulations according three climate change scenario for Kaczawa River a left side tributary of the Odra River in south-west Poland is presented. The flow sequences were simulated using the hydrological model MIKE SHE and the spatial SWGEN meteorological data generator. Meteorological data for the hydrological model were generated based on data from 24 meteorological stations and 35-year daily data from the Institute of Meteorology and Water Management of the National Research Institute (IMGW). Data were generated for future climate condition for 2060 according GISS Model E, HadCM3, and GFDL R15 scenarios as well for the present conditions. The year 2000 was used as a reference year. The results obtained on the basis of a simple time series analysis point to small changes in flows for current and simulated conditions for 2060 for the Kaczawa River.

Parasitic Memcapacitor Effects on HP TiO2Memristor Dynamics

In this paper, we study an HP TiO 2 memristor model with a parasitic memcapacitor, and it is shown that the parasitic element has significant effects on the volt-ampere characteristics and the dynamics of the memristor circuits. Further, the study shows that the pinched point on the hysteresis loop of the HP TiO 2 memristor may deviate from the origin. We also show that the memristor with a parasitic memcapacitor will eventually lose its stored flux when its power is switched off. Furthermore, in order to study the parasitic effects in circuits, we derive a simple three-element series circuit that contains an inductor, a negative resistor, and an HP TiO 2 memristor. If the parasitic memcapacitor of the memristor is considered, we observe a parasitic periodic oscillation occurred in the circuit.

Theoretical study of interface thermodynamic properties of 1,3,5-triamino-2,4,6-trinitrobenzene based polymer bonded explosives

The thermodynamic properties of insensitive high explosive 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) based polymer bonded explosives (PBXs) are investigated by using first principle calculation and molecular dynamics simulation. The results include the phonon dispersion relations, interface thermal conductances, and thermal conductivities of TATB based PBXs. Both TATB and PVDF structures are optimized, in which the optimized lattice constants accord with previous results. The phonon dispersion relation of TATB and PVDF are calculated based on lattice dynamics. All interatomic force constants are calculated by the finite displacement method (numerical derivatives from perturbed supercells). The calculated phonon dispersion relation of TATB and heat capacity are in general agreement with experimental and theoretical results. The imaginary frequencies are observed in both TATB and PVDF dispersion relation. The imaginary frequencies are mainly due to the smaller calculated supercell size and temperature effect. The phonon mode of TATB and PVDF are assigned at Γ point. Based on the calculated phonon dispersion, some information including heat capacity, phonon density of states and phonon mode assignment is derived. The TATB possesses 144 phonon modes including 3 acoustic-phonon modes and 141 optical phonon modes. The anylized phonon mode of TATB shows that -NO&lt;sub&gt;2&lt;/sub&gt; dominates the phonon DOS in low frequency zone, phenyl rings dominate in middle frequency zone and -NH&lt;sub&gt;2&lt;/sub&gt; dominates in high frequency zone. By analyzing the phonon density of states and capacity, both TATB and PVDF imply that low-frequency vibration dominates the thermal conductivity. The thermal conductivity is determined for TATB by using the equlibrium molecular dynamics method and an established TATB force field. The TATB model is built with 2880 atoms. The structure of TATB is optimized by using molecular mechanics, then this system is relaxed by using a Nose-Hoover thermostat and barostat with a damping factor of 50 fs cin time steps of 0.1 fs. The calcultated thermal conductivity at room temperature shows good agreement with experimental result. The interface thermal conductance of TATB-PVDF is calculated by using a diffusive mismatch model. The interface thermal transport still follows Fourier’s law of heat conduction, and ballistic thermal transport mechanism is not involved. By using the above results, the thermal conductivity of mixture TATB-PVDF system is analized with a simple series model. The particle size smaller than 100 nm significantly suppresses the mixture system thermal conductivity.

Starting Darcy–Brinkman Flow in a Sector Duct Using the Method of Eigenfuction Superposition

The powerful method of eigenfunction superposition is applied to the starting flow in a sector duct filled with a porous medium. Using analytic eigenfunctions and eigenvalues of the Helmholtz equation, the solution can be expressed in a simple series. The properties of the velocity and the transient flow rate are found to depend on the sector geometry and a porous medium factor. The starting solution is then used to construct the solution to arbitrary unsteady flows.

Correlations Between the Thermosphere's Semiannual Density Variations and Infrared Emissions Measured With the SABER Instrument.

This paper presents measurements of the amplitudes and timings of the combined, annual, and semiannual variations of thermospheric neutral density, and a comparison of these density variations with measurements of the infrared emissions from carbon dioxide and nitric oxide in the thermosphere. The density values were obtained from measurements of the atmospheric drag experienced by the Challenging Minisatellite Payload, Gravity Recovery and Climate Experiment A, Gravity field and Ocean Circulation Explorer, and three Swarm satellites, while the optical emissions were measured with the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on the Thermosphere Ionosphere Mesosphere Energetics and Dynamics satellite. These data span a time period of 16 years. A database containing global average densities that were derived from the orbits of about 5,000 objects (Emmert, 2009, https://doi.org/10.1029/2009JA014102, 2015b, https://doi.org/10.1002/2015JA021047) was employed for calibrating these density data. A comparison with the NRLMSISE‐00 model was used to derive measurements of how much the density changes over time due to these seasonal variations. It is found that the seasonal density oscillations have significant variations in amplitude and timing. In order to test the practicality of using optical emissions as a monitoring tool, the SABER data were fit to the measured variations. Even the most simple fit that used only filtered carbon dioxide emissions had good correlations with the measured oscillations. However, the density oscillations were also well predicted by a simple Fourier series, contrary to original expectations. Nevertheless, measurements of the optical emissions from the thermosphere are expected to have a role in future understanding and prediction of the semiannual variations.

Pengembangan Media Pembelajaran Virtual dan Interaktif Untuk Mensimulasikan Instalasi Jaringan Listrik di SMK 2 Surakarta

The learning of electrical installation at Vocational High School often comes to problems as the availability of real apparatus or equipment which are not used again on the next period. It is also getting worse as the learning style is not effective by that way in a group. When it is done in a group, certain student will rely on his/her work to other friends. Consequently, they will get no beneficial from the instructional process done. Therefore, it is developed an interactive multimedia of simple electrical series in order to be directly tried by each student easily. At last, they will be motivated and get the benefit from the lesson

Double absolute indexed matrix summability with its applications

The well established theory of summability of simple series has been brought to a high degree of development; however the extension of this theory to multiple series is still in its infancy. As regards to the double series, in the proposed paper a result on absolute indexed matrix summability with an additional parameter of doubly infinite lower triangular matrix has been established that generalizes a theorem of E. Savaş and B. E. Rhoades [10] (see E. Savaş and B. E. Rhoades, Double absolute summability factor theorems and applications, Nonlinear Anal. 69 (2008), 189-200). Furthermore, some concluding remarks and applications are presented in support of our result.

Narratives and Nested-Time

Narratives are often created within a linear time, which allows them to be organized into a simple and discrete series of events. However, narratives can be created outside of linear time, thereby changing the organization of the narrative. To think about this further, we draw from Henri Bergson’s concept of duration and Gilles Deleuze’s ontology of difference to reconsider time in narratives and question the simple temporal organization of events. In doing so we develop the concept of nested-time as a way of playing with time and narrative and encourage narrative researchers to experiment with time and narrative as well.

Are some taxes better for growth in Pakistan? A time series analysis

PurposeThe purpose of this paper is to analyze the impact of taxes on economic growth in the long run as well as in the short run.Design/methodology/approachThe study uses simple time series model, where real GDP is dependent variable and different forms of taxes are explanatory variables under ARDL framework from 1976 to 2014 at annual frequency for Pakistan.FindingsDirect taxes have positive relation with economic growth in the long run. Sales tax, tax on international trade (tariffs) and other indirect taxes have positive impact on economic growth of Pakistan in the long run as well as in the short run. However, sales tax and other indirect taxes impact negatively on economic growth in the short run after one year because people realize decline in their real income.Practical implicationsGovernment should increase direct taxes by increasing tax base. Indirect taxes usually indicate negative impact after one and two years; therefore, government should decrease its reliance on indirect taxes. Government should promote tax awareness among the people which increase the tax morale of people and increase the tax base.Originality/valueTaxes are disaggregated into direct and indirect taxes, while indirect taxes have been further disaggregated into excise duty, sales tax, surcharges, tax on international trade and other indirect taxes. This study provides useful insight for policy makers in designing taxes and their effect on growth.

Thermodynamics of Modularity: Structural Costs Beyond the Landauer Bound

Information processing typically occurs via the composition of modular units, such as universal logic gates. The benefit of modular information processing, in contrast to globally integrated information processing, is that complex global computations are more easily and flexibly implemented via a series of simpler, localized information processing operations which only control and change local degrees of freedom. We show that, despite these benefits, there are unavoidable thermodynamic costs to modularity---costs that arise directly from the operation of localized processing and that go beyond Landauer's dissipation bound for erasing information. Integrated computations can achieve Landauer's bound, however, when they globally coordinate the control of all of an information reservoir's degrees of freedom. Unfortunately, global correlations among the information-bearing degrees of freedom are easily lost by modular implementations. This is costly since such correlations are a thermodynamic fuel. We quantify the minimum irretrievable dissipation of modular computations in terms of the difference between the change in global nonequilibrium free energy, which captures these global correlations, and the local (marginal) change in nonequilibrium free energy, which bounds modular work production. This modularity dissipation is proportional to the amount of additional work required to perform the computational task modularly. It has immediate consequences for physically embedded transducers, known as information ratchets. We show how to circumvent modularity dissipation by designing internal ratchet states that capture the global correlations and patterns in the ratchet's information reservoir. Designed in this way, information ratchets match the optimum thermodynamic efficiency of globally integrated computations.

A simple exact series representation for relativistic perihelion advance

The small discrepancy between the observed orbit of Mercury and the orbit predicted by Newtonian gravity was a key test of Einstein's theory, and a dramatic verification of the correctness of General Relativity. This `anomalous precession' of the perihelion is here calculated using a particularly simple method and resulting in a new and elegant series for the precession which converges very quickly.

Effect of Shunt Capacitances on Performance of Current-Mode Class-DE Power Amplifier at Any Active Time

In this paper, a current-mode Class-DE (CMCDE) power amplifier is presented. The CMCDE with linear shunt capacitance under zero-current switching (ZCS) and zero current-derivative switching (ZCDS) conditions at any active time is analyzed, simulated, and fabricated. An analytical theory along with the design simulation and verification by experimental results at active time $\tau _{d}= \pi / 2$ are given. It was shown that the peak switch voltage can be adjusted with active time $\tau _{d}$ . The proposed amplifier offers several desirable features, such as simple structure and possibility to include the parasitic inductance and shunt capacitance of the mosfet into a load network, so that ZCS condition is maintained. The results show that the switch voltage and current obtained in CMCDE amplifier are inversed in comparison to the voltage-mode Class-DE (VMCDE) amplifier by using a simple output matching network and series inductance. Also, we could control the harmonics in one resonator in comparison to multiple resonators used in some high-efficiency power amplifiers. The measured maximum drain efficiency of 88% and power gain of 22 dB at 42-dBm output power was obtained at 4 MHz for CMCDE amplifier at active time $\tau _{d}= \pi / 2$ .

An Investigation of Temporally Inspired Time Domain Features for Electromyographic Pattern Recognition.

This paper presents a novel set of temporally inspiredtime domain features for electromyographic (EMG) pattern recognition. The proposed methods employ simple time series measures derived from peak detection, and could better reflect EMG activity over time. Multiple EMG datasets consisting of 68 able-bodied and transradial amputee subjects performing a large variety of hand, wrist, fingers, and grasping movements are used to evaluate the performance of the proposed features and to design robust EMG feature sets. The results show that the average classification accuracy of two novel features, the mean prominence of local peaks and valleys, outperform several commonly used time domain features, autoregressive coefficients, histogram, and zero crossing, by 8{\%, 11{\%, and 17{\%, respectively. The proposed features are also shown to provide additional information as part of a robust feature set when compared to the common Hudgins' timedomain feature set, as selected by sequential forward selection and through empirical feature set design.