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Microrobots have been actively studied in recent years due to their mobility and usability. It is important to receive electrical energy from outside through wireless power transfer (WPT) system because active circuits, such as sensors and microrod controller unit, should be included and operating time should be sufficient to increase the usability of microrobot. In this research, we propose a multi-selective WPT coil and structure to maximize the usability of the microrobot that can receive electrical energy with wireless power transmission systems and can be propelled and rotated at the same time. The proposed multi-selective WPT coil system architecture is described with a theoretical explanation of the magnetic force acting on the microrobot. To verify the proposed model, it has been verified through simulation and experimental verification that the time-varying magnetic field generated from four transmitting coils is suitable for the propulsion, generating torque, and power transmission of microrobot. To validate the proposed system, a 3 mm-sized microrobot is used for experimentation. The experimental results show that the microrobot is able to freely move and rotated as intended by controlling the external incident magnetic field.

With increase in real-time systems, users have come to demand information with low latency. However, as the blocklength becomes finite to reduce communication duration, the decoding error probability is newly considered. In this letter, we consider downlink cellular networks, where base stations (BSs) periodically transmit information with finite blocklength to a user. To analyze the freshness of information, we derive the average age of information (AoI) and the AoI violation probability in a closed-form using the upper bound of the average decoding error probability. Finally, we show that an optimal blocklength that minimizes the AoI exists.

A macrocyclic peptide scaffold with well-established structure–property relationship is desirable for tackling undruggable targets. Here, we adopted a natural macrocycle, cyclosporin O (CsO) and its derivatives (CP1–3), and evaluated the impact of conformation on membrane permeability, cyclophilin A (CypA) binding, and the pharmacokinetic (PK) profile. In nonpolar media, CsOshowed a similar conformation to cyclosporin A (CsA), a well-known chameleonic macrocycle, but less chameleonic behavior in a polar environment. The weak chameleonicity of CsOresulted in decreased membrane permeability; however, the more rigid conformation of CsOwas not detrimental to its PK profile. CsOexhibited a higher plasma concentration than CsA, which resulted from minimal CypA binding and lower accumulation in red blood cells and moderate oral bioavailability (F= 12%). Our study aids understanding of CsO, a macrocyclic peptide that is less explored than CsAbut with greater potential for diversity generation and rational design.

This paper introduces the Eighth Dialog System Technology Challenge. In line with recent challenges, the eighth edition focuses on applying end-to-end dialog technologies in a pragmatic way for multi-domain task-completion, noetic response selection, audio visual scene-aware dialog, and schema-guided dialog state tracking tasks. This paper describes the task definition, provided datasets, baselines and evaluation set-up for each track. We also summarize the results of the submitted systems to highlight the overall trends of the state-of-the-art technologies for the tasks.

Owing to its high information density, energy efficiency, and massive parallelism, DNA computing has undergone several advances and made significant contributions to nanotechnology. Notably, arithmetic calculations implemented by multiple logic gates such as adders and subtractors have received much attention because of their well-established logic algorithms and feasibility of experimental implementation. Although small molecules have been used to implement these computations, a DNA tile-based calculator has been rarely addressed owing to complexity of rule design and experimental challenges for direct verification. Here, we construct a DNA-based calculator with three types of building blocks (propagator, connector, and solution tiles) to perform addition and subtraction operations through algorithmic self-assembly. An atomic force microscope is used to verify the solutions. Our method provides a potential platform for the construction of various types of DNA algorithmic crystals (such as flip-flops, encoders, and multiplexers) by embedding multiple logic gate operations in the DNA base sequences.

The electrical conductivity and catalytic activity of nanofibrous poly(3,4-ethylenedioxythiophene)s (PEDOT NFs) was improved by redoping with dimethyl imidazolium iodide (DMII) as a charge transfer facilitator. Addition of the new DMII dopant into the PEDOT NFs reduced the concentration of dodecyl sulfate anions (DS–) predoped during the polymerization process and concomitantly enhanced the doping concentration of I–by ion exchange. Redoping with DMII increased the mobility of the PEDOT NFs by up to 18-fold and improved the conductivity due to the enhanced linearization, suppressed aggregation, and improved crystallinity of the PEDOT chains. The catalytic activity was also improved, primarily due to the increase in the compatibility and the effective surface area upon replacement of sticky DS–with the more basic and smaller I–of DMII on the surface of the PEDOT NFs. The charge-transfer resistance across the interface between the poly(ethylene oxide)-based solid polymer electrolyte and PEDOT NF counter electrode (CE) was thus reduced to a large extent, giving an energy conversion efficiency (ECE) of 8.52% for solid-state dye-sensitized solar cells (DSCs), which is even better than that achieved with Pt CE (8.25%). This is the highest ECE reported for solid-state DSCs with conductive polymer CEs under 1 sun conditions.

If the short-term ageing (SA) level of asphalt mixture is intense before paving, the pavement service life will be reduced due to the highly stiffened binder from the starting time of service. However, since how much the ageing damage is induced by the severe SA is not known, this study was initiated to examine the physical property degradation of the binder in the SA treated mixes. Four SA times (1, 2, 4 and 8 h) at 160°C and 180°C were used for 3 mixes: a dense-graded HMA mix with a normal binder (PG64-22), the same mixes including a hydrated lime (HL; 1.5% by wt. of mix) and a polymer stabiliser (KL; 1.5% by wt. of binder). Increasing patterns of absolute viscosity (AV) and stiffness (G*/sin δ) due to ageing were found to follow the form of exponential function. They were highly increased in 2 h (h) SA, but exceedingly increased in 4 h and longer SA at 180°C. These AV and stiffness increase resulted in DSR critical temperature (CT) escalation and degradation of bending beam rheometer (BBR) CT. The AV, G*/sin δ, DSR CT and BBR CT of the normal mixes were found to have a very high correlation (R2 > 0.98) with large-molecular size (LMS) ratio (%) of gel-permeation chromatography. The binder AV and G*/sin δ of HL and KL mixes were estimated using LMS. In comparison of binder ageing level of mixes with and without HL or KL, it was found that both HL and KL retarded the ageing, but HL more significantly, for longer SA time at higher temperature. Therefore, it was evidenced that the use of HL in the HMA mix should be a highly beneficial choice for preserving durable pavement.

Bloom syndrome protein (BLM) is one of RecQ helicases, which are conserved DNA unwinding enzymes in DNA metabolisms. The RecQ C‐terminal domain (RQC) of BLM is a winged‐helix motif, which recognizes various DNA structures. BLM RQC mediates electrostatic interactions with duplex DNA by using polar residues in the β‐wing and α2–α3 loop. In order to understand the dynamic properties of RQC for recognizing its substrate DNA, we measured 15N spin relaxation parameters of the protein and performed model‐free analysis. Our results showed that the β‐wing region, which is used for the strand separation, has flexible backbone structure. The α2–α3 loop, the binding surface of the DNA major groove, was found to be relatively rigid. Our results contribute to a better understanding of molecular basis of BLM RQC–DNA interaction.

For SPM(Sulfuric acid Peroxide Mixture) cleaning, a widely used method in semiconductor process, the density of peroxide is the main factor for metal and polymer removal. As the technology node shrinks, the need for both better polymer removal performance and less for metal removal is required. However, with only one factor is available for SPM cleaning. In this paper, by electrolysis of sulfuric acid, we utilized peroxydisulfate(S2O82-) instead of peroxide in semiconductor processes, resulting in better residue removal with same amount of metal removal.

Charge transfer between a conducting polymer-based counter electrode (CE) and a polysulfide (S2–/Sn2–) electrolyte mediator is a key limitation to improvements of solar energy conversion efficiency (ECE) in quantum-dot-sensitized solar cells (QDSCs). In this paper, 1,2-ethanedithiol (EDT) was doped into nanofibrous poly(3,4-ethylenedioxythiophene) (PEDOT NF) to overcome the charge transfer limitation between PEDOT NF and S2–/Sn2–. EDT not only helps to reduce the aggregation and thus enhance the linearization of the PEDOT chains but also changes the molecular conformation of the PEDOT chains from a benzoid to a quinoid structure. EDT-doped PEDOT NF-based CEs showed almost 3.7 times higher conductivity, better electrocatalytic activity, and improved compatibility with S2–/Sn2–in an aqueous electrolyte. As a result, the charge transfer resistance between the polymer-based CE and the S2–/Sn2–electrolyte was significantly reduced, resulting in over 3% ECE in QDSCs, more than double that of a bare PEDOT NF-based CE.

A key-value store (KVS), such as memcached and Redis, is widely used as a caching layer to augment the slower persistent backend storage in data centers. DRAM-based KVS provides fast key-value access, but its scalability is limited by the cost, power and space needed by the machine cluster to support a large amount of DRAM. This paper offers a 10X to 100X cheaper solution based on flash storage and hardware accelerators. In BlueCache key-value pairs are stored in flash storage and all KVS operations, including the flash controller are directly implemented in hardware. Furthermore, BlueCache includes a fast interconnect between flash controllers to provide a scalable solution. We show that BlueCache has 4.18X higher throughput and consumes 25X less power than a flash-backed KVS software implementation on x86 servers. We further show that BlueCache can outperform DRAM-based KVS when the latter has more than 7.4% misses for a read-intensive aplication. BlueCache is an attractive solution for both rack-level appliances and data-center-scale key-value cache.

Herein, the energy level alignment and electron recombination kinetics in solid state dye-sensitized solar cells (DSCs) employing a solid polymer electrolyte (SPE) have been quantitatively characterized. In order to determine the microscopic origin of the enhanced characteristics in polymer electrolytes, we carried out an extensive study of the photovoltaic properties with respect to the electrolyte type and composition, including a liquid electrolyte (LE) and various salt types and concentrations. We observed a smaller downward shift in the conduction band energy of the TiO2layer upon contact with the SPE as well as a retarded electron recombination rate. These led to an increase in the Vocfor DSCs with an SPE, which is mostly attributable to the coordinative interactions of the ethylene oxide (EO) units in poly(ethylene oxide) (PEO) and poly(ethylene glycol) dimethyl ether (PEGDME) with metallic Li+ions and Ti atoms. Such coordinative interactions induce 1) the capture of Li+cations in the bulk of the polymer electrolyte, thereby reducing their effective concentration and 2) the facile formation of a PEO passivation layer on top of the TiO2layer. Therefore, it was concluded that the high Vocin solid state DSCs employing a polymer electrolyte is attributable to the coordinative properties of the EO units in PEO and PEGDME in the SPE.

An iterative algorithm used for the design and optimisation of a binary phase computer generated hologram for high-resolution lithography in on-axis and off-axis geometries is presented. A sensitivity analysis is performed to estimate the effect of CGH manufacture errors using electron-beam writing.

As flash memory technologies quickly improve, NAND flash memory-based storage devices are becoming a viable alternative as a secondary storage solution for general-purpose computing systems such as personal computers and enterprise server systems. Most existing flash translation layer (FTL) schemes are, however, ill-suited for such systems because they were optimized for storage write patterns of embedded systems only. In this paper, we propose a new flash management technique called LAST which is optimized for access characteristics of general-purpose computing systems. By exploiting the locality of storage access patterns, LAST reduces the garbage collection overhead significantly, thus increasing the I/O performance of flash-based storage devices. Our experimental results show that the proposed technique reduces the garbage collection overhead by 54% over the existing flash memory management techniques.

Key-value stores (KVS) are now an integral part of modern dataintensive systems. thanks to its simplicity, scalability, and efficiency over traditional database systems. Databases such as MySQL employ KVS (in this case, RocksDB as their backend storage instead of conventional database engines because KVS is less affected by data fragmentation. OLAP and big data analytics applications often use KVS as the backend store to make use of the efficient range_query operations of LSM(Log Structured Merge Tree)-based KVS. Furthermore, the increasing use of KVS as backend stores in distributed systems diversifies the workload for each local KVS, making it necessary to design a highly-concurrent data store that simultaneously processes mixed operations.The underlying technology trends also put immense pressure on the design of KVS. Nowadays, many core servers with hundred GBs of memory are common in production environments, and this enhanced density of hardware technologies (both in terms of the number of cores and memory capacity) leads to more data items residing in memory. This phenomenon places greater emphasis on the efficiency of the in-memory data structure in KVS, as more data accesses are serviced from its memory component, which is often called the memtable. The current memtable structure of KVS, however, generally assumes a limited memory capacity that only serves as a temporary write buffer, and the use of single-threaded writes or unscalable data structures for the memtable fails to fulfill this external demand.