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Panoramic Radiography and Cone Beam Computed Tomography (CBCT) are the most used imaging techniques for implant treatment and oral surgery. However, it cannot be used frequently due to the high cost and radiation exposure of CBCT. Whereas Panoramic x-rays do not provide the high dimensional information necessary for planning surgery. Our research aims to produce an automated method for reconstructing a 3D dental structure from a single panoramic X-ray. This paper presents a robust preprocessing pipeline of CBCT data which are exploited to train a deep learning model for reconstructing the 3D dental structure from a single 2D panoramic X-ray image. It includes a method of generating a pair of synthetic panoramic X-rays and the corresponding flattened 3D volume as ground truth from CBCT data.

Deep learning technologies for skin cancer detection have been dramatically advanced based on high resolution dermoscopic images. The low-cost approach based on clinical skin images of low resolution is promising but remains technically challenging due to their undermined image quality. In this paper, we propose a coarse-to-fine efficient super resolution transformer (CF-ESRT) network to reconstruct the dermoscopy-level high resolution skin image from a low resolution clinical image. By connecting the refinement network to the original super resolution transformers and applying perceptual and gradient losses, our framework noticeably improves the finer texture details of skin lesions in the super resolution (SR) images, and is effective to elevate the perceptual quality of the SR images. Quantitative and qualitative evaluations show that our method outperforms ESRT the basis model as well as the other state-of-the-art SR models.

BACKGROUND Although it has been common to use artificial implant to augment nasal dorsum in Asian rhinoplasty, the demand for not using it is increasing due to the long-term complications of implants. However, if only the tip is raised without raising the dorsum with implant, it is difficult to avoid supratip depression, so it is difficult to obtain good cosmetic results. The authors would like to report good results, performing an augmentation rhinoplasty that raises the supratip area using the nasal septal cartilage without using an implant. METHODS Septal gap graft was used in 22 patients undergoing nasal tip surgery from January 2019 to April 2021. Septal gap graft refers to a graft that increases the height of the supratip area by using septal cartilage. Firstly, the authors perform a septal extension graft using the septal cartilage, then the authors fix the lower lateral cartilage in an ideal position, and lastly the authors heighten the nasal tip with onlay graft. The height difference between the nasal bone and the nasal tip, is solved by placing the septal cartilage. Before, during and after surgery, photometric analysis was done by taking clinical pictures. RESULTS Through the septal gap graft, the supratip depression index was decreased and the nasal tip projection was increased. It was confirmed that the septal gap graft was well maintained at long-term follow-up, and the patients' postoperative satisfaction was also high. CONCLUSIONS The authors presented a new technique for augmentation rhinoplasty in Asians. Septal gap graft can be used safely and effectively to raise supratip area without using implant.

Advancement genioplasty is performed to aesthetically improve the lower third of the facial profile. Excessive chin advancement alone may lead to deepened labiomental sulcus and deformed aesthetic results. The purpose of this study was to assess the efficacy of silicone prosthesis placement as an alternative method for effacing an excessively deepened labiomental groove after advancement genioplasty. Three hundred and seventy-six patients underwent genioplasty between January 2014 and October 2017. Among these were 216 cases of advancement genioplasty, of which 79 (62 females and 17 males) underwent advancement procedures using silicone implants. Inserting the silicone implant at the sulcus easily removes the deepened groove. This procedure could be an easy and reliable method for attaining an aesthetically pleasing result in excessive advancement genioplasty.

Recently, maintenance applications around power lines have been actively studied. These applications usually supply power through magnetic energy harvesting(MEH) to devices around the power line. A major challenge for practical MEH is to overcome magnetic saturation, which can cause degradation of power density under a wide current range in the power line. In this paper, we propose a design methodology to harvest maximized output power by considering the saturation effect. To consider magnetic saturation, the output power model and the saturable magnetizing inductance model based on magnetizing current were comprehensively analyzed. Additionally, the critical point of saturation for the maximum harvested power was analyzed by considering different primary side current conditions. With the proposed design methodology, the accuracy and efficiency of the output model were verified with experimental results compared to the conventional model. To consider the real environment, a 150 kW class of AC resistor load bank was implemented to control the primary current from 0 to 100 A with power frequency of 60 Hz. Experimental results show that the proposed method can harvest an average power of 14.32 W on 70 A power line, which is an increase of 39.8 % compared with the conventional design method.

This brief presents a temperature sensor that combines a leakage-based bandgap-Vth reference and an asynchronous SAR. The proposed sensor is implemented with 0.18 $\mu \text{m}$ CMOS technology. By sampling leakage-based biases directly in the SAR ADC, the sensor consumes 490 pW at 20 °C with a conversion time of 200 ms and stably works with a 1-point calibration, showing a ±2.35 °C peak-to-peak inaccuracy from −10 to 100 °C. The proposed sensor can operate across a wide range of supply voltage of 1 V to 2.1 V, with a supply sensitivity of 1.073 °C/V.

Semiconductor hybrid structures containing multiple components have been considered an ideal photocatalyst design to generate long-lived charge-separated states. Particularly for the reactions requiring high activation energies, such as a CO2 reduction reaction (CO2RR), the reaction activity is highly susceptible to the catalyst component and morphology. In this study, we selected g-C3N4 and Cu2O as photocatalytic components having bandgaps suitable for CO2RR. Then, we tried to form good electric junctions between two domains by direct growth of Cu on g-C3N4 using a polyol process. The resulting g-C3N4/Cu2O hybrid was employed as photocatalysts in an aqueous medium without hole acceptors. The catalyst exhibited a noticeable activity (5.4 mmol gcat-1h-1) and quantum yield (3.7%) with a nearly quantitative selectivity for CH4 production, superior to any other photocatalysts for CO2RR. The strong coordination of g-C3N4 to the Cu2O surface could form a conductive junction and induce effective electron transfer enforcing the Z-scheme process for CO2RR in high activity and selectivity. This result ensured the importance of junctions and interfaces in the hybrid catalyst structure to exhibit excellent photocatalytic CO2RR performances.

In this article, a microrobot capable of creating propulsion force and receiving electrical energy using a wireless power transfer (WPT) system is proposed. As a source of propulsion and rotation for the microrobot, we use the force and torque of magnetic material in a time-variant magnetic field generated by the transmitting coil of the WPT system, with a specifically designed magnetic material which produced even greater force under the same volume. While microrobot propulsion based on the Lorentz force is closely related to the magnitude of the induced current, because the force of the magnetic material in the proposed design is independent of the induced current, it is more practical for miniaturization of the microrobot. Additionally, the proposed model is able to use the LC resonance frequency, and a magnetic material located in the receiving coil introduces a higher coupling coefficient between the transmitting coil and the receiving coil. These characteristics make the proposed microrobot suitable for powering through a WPT system. The feasibility of the proposed model was initially investigated by theoretical analysis and then verified in simulation and an experiment. In the experiment, the fabricated microrobot 4.5 × 2.0 × 2.0 mm 3 in size achieved a power transfer efficiency rate of 4.5% at 103 kHz with a propulsion speed of 7.5 mm/s and rotating motion.

This paper proposed EMI reduction method for over-coupled wireless power transfer (WPT) system using seriesnone (SN) topology. The series-none (SN) topology does not has the compensation capacitor for minimizing reactive power of receiver side. The proposed topology has higher input impedance than conventional series-series (SS) topology, resulting in the odd harmonic components of current for SN topology has lower than that of SS topology. In addition, when the over-coupling phenomena occurs, there is not much difference in efficiency of transferring power compared to SS topology. The proposed method is verified through the 3D EM tool and circuit simulation.

Hypoxic microenvironments emerge as tumor grow, leading to the over-expression and stabilization of hypoxia-inducible factor 1-alpha (HIF-1α). HIF-1α lowers the sensitization against chemotherapy, radiation therapy and photodynamic therapy in cancer. In this study, nano-sized oxygen carrier, namely oxygen dissolved nanoliposome (ODL) was synthesized, and oxygen was efficiently delivered to different types of mammalian cells to help relieve hypoxia. ODL confirmed that oxygen was released without inducing toxicity to cells. After artificially creating hypoxia in cancer cells, normal cells, and immune cells; various parameters such as cell morphology, HIF-1α expression, and degree of hypoxia were examined. The cellular environment was found to be altered by treatment with the ODL. Under hypoxia, the shape of the cells changed, and the cells began to die. After treatment with the ODL, the degree of hypoxia was reduced, indicating that HIF-1α expression and the rate of cell death decreased. Furthermore, bacteria proliferation was observed with the ODL. Therefore, ODL can be used for oxygen delivery platform in cancer therapy. ODL has a potential application in other microorganisms which needs future research.

Recently, magnetic energy harvesting is a promising technologies for self-sustainable operation of devices around power line. However, the magnetic energy harvester has a problem that magnetic core material is saturated at high current condition. In this paper, we analyzed the power harvesting by considering magnetic saturation in magnetic material. Using B-H curve, we analyzed magnetizing inductance according to varying primary current. This analysis makes it possible to predict harvested power in saturated condition, which the conventional method cannot predict. To confirm the validity of this paper, magnetic core materials were fabricated and measured by B-H curve tracer. The experiments were prevailed from 5A to 250A primary current.

The optimal transmitters(TXs) selection method is proposed to operate at maximum power efficiency in a wireless power transfer(WPT) system using multi-TX. The proposed method is determined by the ratio of the coupling coefficients between TXs and RX and is not affected by other parameter. Moreover, the proposed criteria are generalized so that they can be applied according to the number of TXs. The power of 100W is transferred at 87.2% and 76.7% with and without the proposed method, respectively.

For charging the battery of underwater applications, many researches on inductive power transfer (IPT) in conductive medium have been conducted. The researches are mainly focused on the analysis of eddy current loss (ECL). In this paper, the Z-parameters method is used to analyze the characteristics of the coil impedance, power transfer efficiency and ECL by considering the conductivity of medium and operating frequency. The Z-parameters method reflects the ECL as an additional resistive component of coils, which is very useful for system analysis and design process.

An Automated guided vehicle (AGV) that transmit high power requires power to be transmitted with high efficiency to lower power loss. However, if the coupling coefficient is increased to increase power transfer efficiency, frequency splitting occurs, which adversely affects output power and system stability. In this paper, a method to mitigate frequency splitting in a magnetic resonant wireless power transfer (WPT) system for 1.5 kW AGV is proposed. Frequency splitting phenomena are alleviated by using the matching capacitance of the transmitter selected based on the analysis of the phase and reactance of the input impedance when the frequency is split. The use of the selected capacitance results in a stable phase of input impedance, and also improves output power capacity. The proposed method is verified by circuit simulation.

Wireless power transfer (WPT) based microrobot maximize the utilization of microrobot since it can transfer electrical energy wirelessly. Unlikely the static magnetic field microrobot propulsion, the WPT based microrobot uses the magnetic force on magnetic material that generated by time-varying magnetic Held. Expecting and evaluating the magnetic force on a magnetic material under wireless power transfer system is important for it determines the moving velocity of microrobot. In this paper, we derive and evaluate a force on a magnetic bar-type material, which is a source of propulsion force of wireless power transfer based microrobot.

The paper proposed a LCL-LCL topology for reduction of odd harmonic magnetic fields in over-coupled WPT system. The LCL-LCL topology has a simple structure of adding inductors in series to the conventional series-series (SS) topology. The proposed topology has higher input impedance at odd-harmonic frequencies than the conventional one, resulting in small harmonic currents and magnetic fields. The effectiveness of the proposed topology is proven by simulation and experiments.

Cobalt oxide nanoparticles, by surface activation, successfully promoted photocatalytic CO2 reduction with a high efficiency and selectivity in aqueous media. Treatment with N-bromosuccinimide (NBS) resulted in the formation of an active form of Co3O4, removed surfactants, and coordinated Br on the surface, thereby enhancing the catalytic efficiency of CO2 reduction to methane.