3D Localization for Launch Vehicle Using Virtual TOA and AOA of Ground Stations

Wireless Personal Communications - Generally, a ground telemetry station for a launch vehicle (LV) includes a tracking function only; therefore, position measurements for LV depend on received...     

Pentacene-Based Low-Voltage Strain Sensors With PVP/$ hbox{Ta}_{2}hbox{O}_{5}$ Hybrid Gate Dielectrics

Field-controllable pentacene-semiconductor-based strain sensors were fabricated with hybrid gate dielectrics using polyvinyl phenol (PVP) and high-$k$ inorganic tantalum pentoxide $(hbox{Ta}_{2}hbox{O}_{5})$ onto polyethylene naphthalate films. The $hbox{Ta}_{2}hbox{O}_{5}$ gate-dielectric layer combined with a thin PVP layer to form very smooth and hydrophobic surfaces turns out to improve the molecular structures of pentacene films significantly. The PVP– $hbox{Ta}_{2}hbox{O}_{5}$ hybrid-gate-dielectric films exhibit a high dielectric constant of 19.27 and a leakage-current density of as low as 100 $hbox{nA/cm}^{2}$ . The sensors employing a thin-film-transistor-like Wheatstone bridge configuration able to operate at reduced voltage ($sim$4 V) show good device characteristics with a field-effect mobility of 1.89 $hbox{cm}^{2}/hbox{V} cdot hbox{s}$ and a threshold voltage of $-$0.5 V. The strain sensor characterized with bending at 45$^{circ}$ with respect to the bridge bias direction with different bending radii of 50-, 40-, 30-, 20-, and 8-mm displays output signals improved in linearity in a low range of operating voltages.      

High-Performance Al–Sn–Zn–In–O Thin-Film Transistors: Impact of Passivation Layer on Device Stability

We fabricated high-performance thin-film transistors (TFTs) with an amorphous-Al–Sn–Zn–In–O (a-AT-ZIO) channel deposited by cosputtering using a dual Al–Zn–O and In–Sn–O target. The fabricated AT-ZIO TFTs, which feature a bottom-gate and bottom-contact configuration, exhibited a high field-effect mobility of 31.9 $ hbox{cm}^{2}/hbox{V}cdothbox{s}$, an excellent subthreshold gate swing of 0.07 V/decade, and a high $I_{{rm on}/{rm off}}$ ratio of $≫hbox{10}^{9}$, even below the process temperature of 250 $^{circ}hbox{C}$. In addition, we demonstrated that the temperature and bias-induced stability of the bottom-gate TFT structure can significantly be improved by adopting a suitable passivation layer of atomic-layer-deposition-derived $hbox{Al}_{2} hbox{O}_{3}$ thin film.      

Discrete Logarithm Problems with Auxiliary Inputs

Let g be an element of prime order p in an abelian group, and let α∈? _p . We show that if g,g ^α , and \(g^{\alpha^{d}}\) are given for a positive divisor d of p?1, the secret key α can be computed deterministically in \(O(\sqrt{p/d}+\sqrt{d})\) exponentiations by using \(O(\max\{\sqrt{p/d},\sqrt{d}\})\) storage. If \(g^{\alpha^{i}}\) (i=0,1,2,…,2d) is given for a positive divisor d of p+1, α can be computed in \(O(\sqrt{p/d}+d)\) exponentiations by using \(O(\max\{\sqrt{p/d},\sqrt{d}\})\) storage. We also propose space-efficient but probabilistic algorithms for the same problem, which have the same computational complexities with the deterministic algorithm.As applications of the proposed algorithms, we show that the strong Diffie–Hellman problem and related problems with public \(g^{\alpha},\ldots,g^{\alpha^{d}}\) have computational complexity up to \(O(\sqrt{d}/\log p)\) less than the generic algorithm complexity of the discrete logarithm problem when p?1 (resp. p+1) has a divisor d≤p ^1/2 (resp. d≤p ^1/3). Under the same conditions for d, the algorithm is also applicable to recovering the secret key in \(O(\sqrt{p/d}\cdot \log p)\) for Boldyreva’s blind signature scheme and the textbook ElGamal scheme when d signature or decryption queries are allowed.     

A Provable Billing Protocol on the Current UMTS

This paper proposes a simple method that equips UMTS-based telecom companies with a mechanism to prove the records on mobile users’ phone bills. In the history of mobile phone communication, we have seen countless unsettled disputes where the mobile user disagrees with the telecom company either on the calling time or on the duration, or even on whether or not a call was actually made. In this paper, a provable billing protocol will be presented that can effectively solve disagreements between the two parties. Equipped with a non-repudiation function, the proposed protocol enables the service provider to hold on to the solid proofs as to exactly when and to which number a mobile phone user made a call so that the mobile user cannot deny; at the same time, the mobile user also gets to have his/her own share of proofs as to when and how the mobile services were accessed, so that the bill can be double checked to make sure nothing goes wrong. And, to make it even better, this new protocol is perfectly compatible with the standard UMTS protocol and is therefore readily applicable to the current mobile phone communication environments.     

Large-Scale Synthesis of Graphene Films by Joule-Heating-Induced Chemical Vapor Deposition

We report large-area synthesis of few-layer graphene films by chemical vapor deposition (CVD) in a cold-wall reactor. The key feature of this method is that the catalytic metal layers on the SiO₂/Si substrates are self-heated to high growth temperature (900°C to 1000°C) by high-current Joule heating. Synthesis of high-quality graphene films, whose structural and electrical characteristics are comparable to those grown by hot-wall CVD systems, was confirmed by transmission electron microscopy images, Raman spectra, and current–voltage analysis. Optical transmittance spectra of the graphene films allowed us to estimate the number of graphene layers, which revealed that high-temperature exposure of Ni thin layers to a carbon precursor (CH₄) was critical in determining the number of graphene layers. In particular, exposure to CH₄ for 20 s produces very thin graphene films with an optical transmittance of 93%, corresponding to an average layer number of three and a sheet resistance of ~600 Ω/square.     

Blockchain Network Based Topic Mining Process for Cognitive Manufacturing

Wireless Personal Communications - Cognitive manufacturing has brought about an innovative change to the 4th industrial revolution based technology in combination with blockchain distributed...     

Differential Game for Distributed Power Control in Device-to-Device Communications Underlaying Cellular Networks

Wireless Personal Communications - In the formulating of power control for wireless networks, the radio channel is commonly formulated using static models of optimization or game theory. In these...     

Deep Neural Architecture for Recovering Dropped Pronouns in Korean

Pronouns are frequently dropped in Korean sentences, especially in text messages in the mobile phone environment. Restoring dropped pronouns can be a beneficial preprocessing task for machine translation, information extraction, spoken dialog systems, and many other applications. In this work, we address the problem of dropped pronoun recovery by resolving two simultaneous subtasks: detecting zero-pronoun sentences and determining the type of dropped pronouns. The problems are statistically modeled by encoding the sentence and classifying types of dropped pronouns using a recurrent neural network (RNN) architecture. Various RNN-based encoding architectures were investigated, and the stacked RNN was shown to be the best model for Korean zero-pronoun recovery. The proposed method does not require any manual features to be implemented; nevertheless, it shows good performance.