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Axial-flux permanent magnet synchronous motors (AFPMSMs) have higher torque densities than the conventional radial-flux permanent magnet synchronous motors (RFPMSMs). However, RFPMSMs have the advantage of lower eddy current losses in the core, owing to the use of electrical steel plates that can be stacked. Therefore, most studies on reducing the eddy current losses of the extant AFPMSMs cores have been focused on reducing the eddy current loss by using a soft magnetic composite (SMC) material or rolling an amorphous electrical steel plate. The method, which is proposed for reducing the eddy current loss of AFPMSMs in this paper, utilizes 3D printing technology to insert a 3D-printed SMC core into the stator shape of a motor that generates a large amount of eddy current; it also inserts air insulation to produce the same effect as that produced by the extant RFPMSM stacking method. The eddy current loss of a stator insulation structure using the 3D-printed SMC core is compared to that of an AFPMSM using the extant SMC core, and the validity of the proposed shape is verified through finite element analysis.

This paper describes two experiments aimed at exploring the relationship between linguistic aspects and perceived proficiency in read and spontaneous speech. 5,000 utterances of read speech by 50 non-native speakers of Korean in Experiment 1, and of 6,000 spontaneous speech utterances in Experiment 2 were scored for proficiency by native human raters and were analyzed by factors known to be related to perceived proficiency. The results show that the factors investigated in this study can be employed to predict proficiency ratings, and the predictive power of fluency and pitch and accent accuracy is strong for both read and spontaneous speech. We also observe that while proficiency ratings of read speech are mainly related to segmental accuracy, those of spontaneous speech appear to be more related to pitch and accent accuracy. Moreover, proficiency in read speech does not always equate to the proficiency in spontaneous speech, and vice versa, with Pearson’s per-speaker correlation score of 0.535.

A flexible vertical-channel structure thin-film transistor (VTFT) was proposed and fabricated on poly(ethylene naphthalate) (PEN) substrate. All the layers composing the gate-stack including an In-Ga-Zn-O (IGZO) active channel were prepared by atomic-layer deposition except for source and drain electrodes. A polyimide was introduced as a spacer material and a dry etch process was designed to form the vertical sidewalls. The fabricated flexible IGZO VTFTs exhibited sound transfer characteristics showing the on/off ratio of 1.8×102. The threshold voltage instabilities were estimated to be +6.1 V/-4.5 V under the positive/negative bias stress tests, respectively. The device characteristics did not show any marked degradation even after the substrate delamination and even under the bending state at a curvature radius of 10 mm.

Effects of ALDsgrown Al 2 O 3 buffer layer on the device characteristics of the flexible amorphous InGaZnO (IGZO) thin film transistors (TFTs) fabricated on ultra-thin polyimide films were investigated. The TFT with a buffer layer exhibited a saturation mobility of 8.6 cm2/Vs and a subthreshold swing of 0.16 V/dec, which was superior to those of the TFT without a buffer layer. Furthermore, under negative bias temperature stress, the turn-on voltage (V on ) instabilities for the TFTs with and without the buffer layer were estimated to be −1.0 and −13.2 V, respectively, owing to the adsorption of water molecules on the PI surface resulting in positively-charged surface. Flexibility of the fabricated IGZO TFT was also evaluated. The V on experienced only a slight negative shift even under the severe bending condition of a curvature radius of 1 mm.

Oxide-semiconductor-based charge-trap memory thin-film transistors were analyzed in order to figure out the origins of the electrical failure under bending situations. Accurate evaluation on the transfer characteristics and visual inspection of electronic devices on plastic substrate were conducted by using modified bending jigs. Electrical failures of the devices were found to be attributed to the micro-cracks developed in inorganic barriers corresponding to the back-channel regions. Variations in threshold voltage and program speed were also observed before the final failure. These results will be of great help in designing flexible nonvolatile memory devices because there are few researches on the charge-trap mechanism affected by the mechanical stress.

We fabricated high resolution electron beam with carbon nanotube cold cathode for microscopy application. The electron beam shows a resolution of 165 μm with phosphor light area measurement and higher emission current more than 60 μA. The electron beam has 9 individual electron sources with CNTs. The electron emission current depend on the length and pitches between CNT emitters. The isolated individual 9 emitters grown with optimized process with dc-PECVD.

The increasing demand for learning Korean as a foreign language yields a strong need for a CAPT system that is able to provide automatic tutoring. However, there is limited research on Korean pronunciation produced by non-natives. As a preliminary research towards developing a CAPT system for Chinese learners of Korean, we survey key findings of previous studies. And then, based on corpus analysis, we provide improved descriptions of segmental variation patterns of Korean produced by Chinese learners. The most salient variation is substitutions of liquid sounds: 33.0% of flap sounds were realized as lateral, and 35.0% of lateral sounds were realized as 3 major variation patterns. By quantifying all the variation patterns with statistical data, we resolve disagreements between previous studies, indicate new findings, which are important resources for developing a CAPT system, and lay the groundwork for Korean language learning for various L1 backgrounds.

Logistics is a crucial ingredient in the operation of an organization. Here how to efficiently deliver the supplies to the consumers in the field under the given condition is the key issue. The general logistics system is usually too complex to be modeled mathematically, or the models are overly computation intensive to be applied in real-time environment. This paper proposes a new method for logistics based on multi-agent system using modified A* algorithm to find the best route between the agents. In addition, genetic algorithm and K-medoids algorithm are used for selecting and clustering the agents to maximize the throughput of logistics. Computer simulation verifies the efficiency of the proposed scheme for a complicated application domain of military logistics.

Recently, several studies have been conducted on the use of optical fibers in the field of photonic technologies. In fact, photonic applications have been developed for various functions including entertainment, communications, and safety protection. However, studies on the applications of flexible optical fiber to smart photonic clothing and luminescence effects are few. The present paper reports on the optimum condition of luminescence effects and the uniform surface through a experimental study of plastic optical fiber(POF)-based flexible textile using different methods of weaving and electronic packaging focused on the red right. For this purpose, we first assessed the differences in the luminance values based on whether etching of the POF-based flexible textile was done and on whether a reflective fabric backing was used. We also analyzed the difference between the luminance values with and without an optical lens on the light source.

A 65 nm HDMI TX PHY was designed with supply-regulated dual-tuning PLL and blending multiplexer. The proposed PLL uses a new dual-tuning scheme for small capacitor and low-jitter while keeping the supply regulation capability. A fractional-N operation for non-integer pixel clock generation was implemented with a blending multiplexer which enables seamless switching of high-speed multiphase clock. The fabricated PHY gives maximum 3.4 Gbps data rate per channel and shows 34 ps peak-to-peak data jitter.

A low-jitter added 3GHz spread-spectrum clock generator (SSCG) with seamless phase selection and a fast automatic frequency calibration (AFC) was implemented in 90nm CMOS process. The proposed SSCG takes full advantage of multi-phase switching with increased sigma-delta operation speed. Large frequency shift and low jitter addition is obtained without extra phase management logic. A new AFC is also proposed for multi-band LC-VCO used in the SSCG. A fast and high resolution frequency calibration is done with direct counting of high frequency VCO clock. The experimental result shows that only 2.7ps peak-to-peak jitter is added by spread-spectrum clocking (SSC) and 400ns of unit frequency comparison time is achieved in AFC process.

Label Switched Paths (LSPs) in a MPLS network sometimes fail to deliver user traffic in the condition of the connection fault. In this case, control messages are exchanged among nodes, and the fault is notified. Nevertheless, there is a need that this fault such as traffic black holes or misrouting should be detected and isolated by the users in MPLS network. For this purpose, the ping and the traceroute especially for MPLS were proposed in the IETF. In this paper, we describe how this proposal is implemented in our test bed and the detail algorithm of this proposal is introduced. Finally, we show how our algorithm test is conducted in our network.

A novel energy-recovery driver is proposed to efficiently drive a plasma display panel (PDP) in the sustaining operation. The proposed circuit can achieve zero-voltage switching (ZVS) for clamping switches and zero-current switching (ZCS) for resonant switches and diodes for all modes of operation. The charging/discharging energy of the panel capacitance can be recovered through the regenerative transformer without additional components.