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X-ray fluorescence (XRF) imaging for metal nanoparticles (MNPs) is a promising molecular imaging modality that can determine dynamic biodistributions of MNPs. However, it has the limitation that it only provides functional information.In this study, we aim to show the feasibility of acquiring functional and anatomic information on the same platform by demonstrating a dual imaging modality of pinhole XRF and computed tomography (CT) for gold nanoparticle (GNP)-injected living mice.By installing a transmission CT detector in an existing pinhole XRF imaging system using a two-dimensional (2D) cadmium zinc telluride (CZT) gamma camera, XRF and CT images were acquired on the same platform. Due to the optimal X-ray spectra for XRF and CT image acquisition being different, XRF and CT imaging were performed by 140 and 50 kV X-rays, respectively. An amount of 40 mg GNPs (1.9 nm in diameter) suspended in 0.20 ml of phosphate-buffered saline were injected into the three BALB/c mice via a tail vein. Then, the kidney and tumor slices of mice were scanned at specific time points within 60 min to acquire time-lapse in vivo biodistributions of GNPs. XRF images were directly acquired without image reconstruction using a pinhole collimator and a 2D CZT gamma camera. Subsequently, CT images were acquired by performing CT scans. In order to confirm the validity of the functional information provided by the XRF image, the CT image was fused with the XRF image. After the XRF and CT scan, the mice were euthanized, and major organs (kidneys, tumor, liver, and spleen) were extracted. The ex vivo GNP concentrations of the extracted organs were measured by inductively coupled plasma mass spectrometry (ICP-MS) and L-shell XRF detection system using a silicon drift detector, then compared with the in vivo GNP concentrations measured by the pinhole XRF imaging system.Time-lapse XRF images were directly acquired without rotation and translation of imaging objects within an acquisition time of 2 min per slice. Due to the short image acquisition time, the time-lapse in vivo biodistribution of GNPs was acquired in the organs of the mice. CT images were fused with the XRF images and successfully confirmed the validity of the XRF images. The difference in ex vivo GNP concentrations measured by the L-shell XRF detection system and ICP-MS was 0.0005-0.02% by the weight of gold (wt%). Notably, the in vivo and ex vivo GNP concentrations in the kidneys of three mice were comparable with a difference of 0.01-0.08 wt%.A dual imaging modality of pinhole XRF and CT imaging system and L-shell XRF detection system were successfully developed. The developed systems are a promising modality for in vivo imaging and ex vivo quantification for preclinical studies using MNPs. In addition, we discussed further improvements for the routine preclinical applications of the systems.

We present a design overview of the MIT 1.3-GHz LTS/HTS NMR magnet (1.3G) with a newly designed 835-MHz REBCO insert (H835) as a replacement for the 800-MHz REBCO insert (H800) that was damaged when it quenched during operation in 2018. The new H835 is designed to contribute 19.6 T in a background field of 10.93 T by an LTS NMR magnet that normally rated at 11.74 T (500 MHz): combined, 1.3G generates a total field of 30.53 T corresponding to a proton resonance frequency of 1.3 GHz. H835 is designed to operate stably while meeting 1.3G design constraints. We have also designed H835 to protect it from permanent damage in an improbable event like a quench. Key design features are: 1) a single-coil formation, composed of 38 stacked metal-co-wound no-insulation and 2 stacked no-insulation double-pancake coils, all with mechanically improved cross-over sections; 2) enhanced thermal stability; and 3) reduced current margin with a detect-and-heat method. This paper includes: 1) electromagnetic and mechanical design of H835; 2) cryogenics overview; 3) quench protection strategy; and 3) discussion on the next steps to successfully complete 1.3G.

In recent years, a new quench protection system using capacitor and switches has been announced to rapidly extract energy from high temperature superconducting (HTS) magnets. When a quench occurs, the quench protection system activates four metal oxide-semiconductor field-effect transistor switches in sequence, and the energy stored in the magnet is extracted by a capacitor to an external resistor. To verify the feasibility of the proposed dual-capacitor switching (DCS) quench protection system, DCS system was tested using a small-scale coil with a 3.3 mH self-inductance. The experimental results show that the energy extraction of the magnet is faster than the quench protection system using a conventional dump resistor. However, as the system is sensitive to the capacitance, inductance, and four resistances, it is necessary to analyze and optimize the design parameters for an application to various magnet systems. In this study, a modified DCS system is introduced to remove the constraints of capacitance, and the effect of all the design parameters on DCS protection performance is analyzed. The optimal design of modified DCS protection system for the best performance is determined. The performance of the system is also evaluated by applying a design that is optimized for the scale-up HTS coil with a 30 mH self-inductance.

A 9 T NbTi superconducting magnet with a large bore is designed and will be fabricated for an EMPS (electro-magnetic property measurement system) whose sample space is 50 mm in diameter. To match the large sample space of the system, the winding bore of the magnet should exceed 89 mm in diameter. Because the winding diameter is much larger than a conventional 9 T class NbTi superconducting magnets, wire selection and magnet design are very important and difficult in this research. An optimal design process with a genetic algorithm considering the critical current, magnetic stress, thermal stability and field uniformity is carried out to develop the 9 T large bore NbTi EMPS magnet. The design algorithm calculates the structure and dimensions of the magnet to minimize the total volume while satisfying the constraints related to the stability of the magnet [Jang et al. (2018)]. To evaluate the thermal stability of the magnet with a protection circuit, a quench analysis is also implemented considering the two boundaries among three adjacent coaxial NbTi coils. The maximum hot spot temperature of the magnet is calculated based on the quench analysis model via a numerical analysis and an electrical circuit simulation. After the optimized design is created, fabrication of the 9 T large bore NbTi magnet will be conducted for its application to the large bore EMPS.

Screening currents in REBCO conductors, induced by time-varying magnetic fields, not only affect the field quality of HTS coils but also cause strain gradients along REBCO tape width that may overstress REBCO conductors used in NMR and other high-field magnets. In this paper, we present results of an experimental and analytical study on screening-current-induced strain gradients, performed with small REBCO pancake coils. Because we believe that screening current effect is reduced in multifilament conductor, we have studied 2 test coils, φ150 mm, one wound with monofilament and the other with 3-striate/4-filament REBCO tapes. A 5-T/ 300-mm room-temperature bore magnet was used not only to excite a strong screening current but also apply the nonuniform Lorentz force to each coil at 4.2 K. Our experiment and analysis have quantitatively demonstrated that we can effectively suppress the screening-current effect on strain gradient, not surprisingly, by using striated multifilament REBCO conductor.

We have finalized the design of a full-scale tabletop 1.5-T/90-mm MgB $_2$ finger MRI magnet system for osteoporosis screening based on our preliminary test results of small coils and superconducting joints. The magnet will operate in persistent mode at 10 K with an additional 5 K temperature margin. The magnet design which includes six main coils and an iron shield satisfies the required specification of a field intensity of 1.5 T, homogeneity of $\leq$ 5 ppm over a 20-mm diameter of spherical volume, and a fringe field of $\leq$ 5 gauss at 0.5 m in radius from the magnet center. An active protection method using external heaters will be applied to prevent a local hot spot in the MgB $_2$ windings from being overheated when quench occurs. Active shield transverse and axial gradient coils for this tabletop osteoporosis MRI, having primary and shield coil pairs, are designed to minimize stray fields that can induce eddy currents on nearby metal surface and thus imaging artifacts. This paper covers design and analysis of: 1) the main coils and iron shield; 2) coil former; 3) quench protection; and 4) active shield gradient coils. We also discuss design changes of the cryostat and equipment plan for the overall system. The magnet system will be completed and then, equipped with other MRI hardware components including an in-house-made gradient coil assembly and RF coils for demonstration of 1.5-T finger MRI in 2020.

In this paper we present quench analysis results of a Low-Temperature Superconducting (LTS) quadrupole triplet magnet system, a part of the In-flight Fragment (IF) separator of a heavy ion linear accelerator complex, named RAON, currently being constructed by the Institute of Basic Science (IBS). This magnet system is composed of three quadrupole magnets: a triplet, surrounded by iron yokes and embedding hexapole/octupole LTS coils for field correction. The magnet will be operated at 4.2 K in liquid helium. For reliable and safe operation of this complex superconducting system, quench and protection analysis with possible failure scenarios must be performed. In this paper, we first discuss probable quench scenarios and then present results of the quench propagation analysis on: 1) coil currents and voltages by multi-coil model circuit analysis; and 2) simulated temperature distribution inside each coil. Our quench analysis results show that the maximum voltage and temperature in each coil are below safety limits, 2000 V and 150 K, respectively, and confirm that this quadruple triplet magnet system is self-protecting.

Quadruple magnets are used as superconducting magnets in accelerator systems and to focus the accelerated beam particles. Therefore, studies are being conducted to implement HTS quadruple magnets in hot cell regions that possess high heat loads in accelerator systems. Additionally, studies on air-core HTS quadruple magnet (AHQM), which do not possess an iron yoke, are also being carried out. This magnet is suitable for the use in hot cell regions and generates a higher magnetic field. Further, magnetic field characteristic of the magnet are linear with respect to the operating current. However, the magnetic field of an AHQM can be the sensitively affected by manufacturing and assembly errors because the iron yoke is removed. After the manufacturing of the magnet, magnetic field shimming is used to compensate for magnetic field errors. This paper presents the optimum design and process for the copper wire bunch active shim (CBAS) method. Furthermore, a test model of the CBAS method is constructed based on the design, and the characteristics and applicability of the proposed model are analyzed.

Triple-negative breast cancer (TNBC) does not have defined therapeutic targets and is currently treated with chemotherapy only. Kinase dysregulation triggers cancer cell proliferation and metastasis and is a crucial therapeutic target for cancer. In this study, targeted kinome sequencing of TNBC tumors was performed to assess the association between kinome gene alterations and disease outcomes in TNBC.A kinome gene panel consisting of 612 genes was used for the targeted sequencing of 166 TNBC samples and matched normal tissues. Analyses of the significantly mutated genes were performed. Genomic differences between Asian and non-Asian patients with TNBC were evaluated using two Asian TNBC datasets (from Seoul National University Hospital [SNUH] and Fudan University Shanghai Cancer Center [FUSCC]) and three non-Asian TNBC datasets (The Cancer Genome Atlas [TCGA], METABRIC, and Gustave Roussy). The prognostic value of kinome gene mutations was evaluated using tumor mutational burden (TMB) and oncogenic pathway analyses. Mutational profiles from the TCGA were used for validation.The significantly mutated genes includedComprehensive analyses of kinome gene alterations in TNBC revealed genomic alterations that offer therapeutic targets and should help identify high-risk patients more precisely in future studies.

Uveal melanoma(UM) is the most common primary intraocular malignancy in adults. However, the incidence of UM in Asia is 10 to 20 times less than in Western populations. Therefore, for the first time, we report our whole exome sequencing (WES) data analysis to discover differences in the molecular features of Asian and Western UM, and to determine the disparities between the primary tumor before brachytherapy and enucleated samples after brachytherapy. WES of 19 samples (13 primary tumors, 5 enucleation samples after brachytherapy, and 1 liver metastasis) from 13 patients diagnosed with UM and treated between 2007 and 2019 at the Yonsei University Health System (YUHS) were analyzed using bioinformatics pipelines. We identified significantly altered genes in Asian UM and changes in mutational profiles before and after brachytherapy using various algorithms. GNAQ, BAP1, GNA11, SF3B1 and CYSLTR2 were significantly mutated in Asian UM, which is similar that reported frequently in previous Western-based UM studies. There were also similar copy number alterations (M3, 1p loss, 6p gain, 8q gain) in both groups. In paired comparisons of the same patients, DICER1 and LRP1B were distinctly mutated only in tumor samples obtained after brachytherapy using rare-variant association tests (P = 0.01, 0.01, respectively). The mutational profiles of Asian UM were generally similar to the data from previous Western-based studies. DICER1 and LRP1B were newly mutated genes with statistical significance in the regrowth samples after brachytherapy compared to the primary tumors, which may be related to resistance to brachytherapy.

The high-temperature superconducting magnets with high magnetic field can store a relatively large amount of energy because of their large inductance and operating current. The magnetic energy stored in the magnet is converted into heat energy when a quench occurs, and the heat generated by the quench resistance and magnet current is sufficient to damage the magnet. Therefore, the large amount of energy stored in a superconducting magnet must be removed quickly to protect the magnet. In this paper, a new quench protection method using a capacitor and dual-switches is proposed and compared to a conventional energy extraction system that uses only a dump resistor. The simulation and test results show that this new protection system is a feasible method for reducing the temperature increase by rapidly reducing the magnet current when a quench occurs.

An air-core high-temperature superconducting quadruple magnet (AHQM) is composed of high-temperature superconductor (HTS) coils without an iron yoke. An AHQM exhibits magnetic field characteristics that vary linearly with respect to changes in the operating current. Further, the AHQM is more suitable for use in high heat load regions. A conventional iron-core quadruple magnet (IQM) contains an iron yoke to achieve the specific shape and magnitude of the magnetic field. In the case of IQMs, the iron yoke generates most of the magnetic field. In the case of AHQMs, the magnetic fields are generated solely by HTS coils. Thus, an AHQM requires a larger number of coils to generate a magnetic field, because the iron yoke has been removed. Consequently, the influence of manufacturing errors in the AHQM is high; these errors deteriorate the designed magnetic field. Therefore, magnetic field correction is required to reduce the deterioration in the magnetic field of an AHQM. This paper, proposes a novel active shim method to compensate for the deteriorated magnetic field of an AHQM. This method improves the uniformity, but does not affect the gradient and effective length of the quadruple magnet. The effectiveness of this method is verified by simulation.

Our research team has developed a wireless power charging system for a high-speed superconducting magnetic levitation train based on the strong resonance coupling method to improve the transfer efficiency and stability. Especially, the range of resonance frequency is one of main key design parameters to fabricate the system since the high resonance frequency can improve the transfer distance easily. On the other hand, since the sensitivity of impedance matching between antenna and receiver coils is increased in the range of higher frequency, the technique of stable impedance matching design including elaborated rectifying subcircuit has been required to commercialize under high-power transfer applications. For this reason, the various transfer characteristics under different ranges for resonance frequency conditions should be evaluated to accomplish improve the transfer efficiency. Thus, in this paper, the transfer efficiency of the moving position of receiver (Rx) coil and consumption of liquid nitrogen were measured at 100 and 370 kHz with 250 W, respectively. In addition, the operating characteristics of the cooled copper Rx and HTS Rx coil were evaluated under 100 and 370 kHz with 250 W, respectively.

Field homogeneity of a superconducting magnet is a critical factor for nuclear magnetic resonance (NMR) spectrometers. For REBCO high-temperature superconducting (HTS) coil fabrication, layer-wound is considered a better option than double-pancake (DP) winding, in terms of field homogeneity. Nonetheless, DP winding is preferred to layer-wound owing to the ease of manufacturing and the difficulty in making long REBCO tapes. However, DP winding has an inevitable crossover turn between the top and bottom layers. For magnets with an HTS insert used in NMR spectrometers, the crossover turn could be critical for the field homogeneity. In this paper, the magnetic field generated by the crossover turn is derived based on the Biot-Savart law, and the effect of crossover turns in stacked DPs on the field homogeneity of an NMR-class HTS magnet is analyzed.

Simple Summary We have developed and analytically validated the Korean Pan-cancer Companion Diagnostic (CDX) Panel to apply targeted anticancer drugs to Korean patients based on the molecular characteristics of tumors using tumor samples without matched patient normal samples. The panel included 31 genes with reported single nucleotide variants, 9 genes with reported copy number variations, and 15 genes with predictive responses to targeted drugs under clinical testing, enabling the panel to be analyzed for the targets of 30 targeted anticancer drugs. It is cost-effective and optimized for cancer type-specific therapy in Korean cancer patients across solid cancer types while minimizing the limitations of existing approaches. This gene screening method is expected to reduce test turnaround time and cost, making it a balanced approach to investigate solid cancer-related gene regions. Abstract Recently, several panels using two representative targeting methods have been developed but they do not reflect racial specificity, especially for Asians. We have developed and analytically validated the Korean Pan-cancer Companion Diagnostic (CDX) Panel to apply targeted anticancer drugs to Korean patients based on the molecular characteristics of tumors using tumor samples without matched patient normal samples. The panel included 31 genes with reported single nucleotide variants, 9 genes with reported copy number variations, and 15 genes with predictive responses to targeted drugs under clinical testing, enabling the panel to be analyzed for the targets of 30 targeted anticancer drugs. It is cost-effective and optimized for cancer type-specific therapy in Korean cancer patients across solid cancer types while minimizing the limitations of existing approaches. In addition, the optimized filtering protocol for somatic variants from tumor-only samples enables researchers to use this panel without matched normal samples. To verify the panel, 241 frozen tumor tissues and 71 formalin-fixed paraffin-embedded (FFPE) samples from several institutes were registered. This gene screening method is expected to reduce test turnaround time and cost, making it a balanced approach to investigate solid cancer-related gene regions.

The No-Insulation (NI) winding provides intrinsic bypassing current paths that enable self-protection from overheating. The self-protection of the NI coil is one of the most promising protection techniques for the high field high-temperature superconductor (HTS) magnet applications. Since the additional paths are valid for an HTS magnet with a thinner matrix, the self-protection mechanism is applicable even for the higher current density magnet with reduced matrix thickness inside the HTS tape. However, reducing the matrix can cause damage to the magnet by producing excessive heat during the quench. This research introduces a new modeling method to investigate the hot-spot characteristics in the REBCO NI pancake coil. The model is also validated with a sample NI HTS coil experiment result. Radial direction Normal Zone Propagation (NZP) velocity of the sample coil is estimated based on the suggested model. The calculated radial direction NZP velocity is applied to calculate the center field drop of the NI HTS coil, and the result is well-matched with the experiment result. We also introduce one example of the model applications. The maximum current density that will not exceed a given reference temperature in the adiabatic cooling condition is estimated using the model.

We suggested an MgB(2) joint process with its own heat-treatment schedule to apply it for our 1.5-T MgB(2) “finger” MRI magnet. In fabricating the MgB(2) magnet, the optimal heat-treatment schedule to attain a reproducible and high critical current is different in a joint and a coil. To solve this problem, we introduced an additional heating system, which is composed of a cartridge heater and a thermocouple connected with a copper block, into a box-type furnace. Then, we carried out heat-treatments with exclusively increasing the joint-part temperature above the Mg melting point of 645 °C—the joint was actually heated up to 700 °C. We evaluated a critical current and a crystal structure of the obtained MgB(2) joint. From experimental results, we found that the joint heated with the own heat-treatment schedule, which is 700 °C for 1 h + 600 °C for 11 h, showed a good I(c) of over 450 A at 15K under self-field. The joint resistance was estimated by the coil operation for 18 days, and it was expected to be less than 10(−12) Ω.

Background: It is unclear whether stemless shoulder prosthesis lead to better clinical outcomes than conventional stemmed shoulder prosthesis. The purpose is to compare clinical outcomes and complication rates after surgery in patients with shoulder arthropathy treated with stemless or conventional stemmed shoulder prosthesis. Method: All studies comparing the constant score (CS), range of motion (ROM), and complication rates after surgery in patients with shoulder arthropathy treated with stemless or conventional stemmed shoulder prosthesis were included. The major databases MEDLINE, EMBASE, the Cochrane Library, Web of Science, and SCOPUS were searched for appropriate studies from the earliest available date of indexing through March 31, 2019. No restrictions were placed on language of publication. Results: A total of 6 studies met the inclusion criteria and were analyzed in detail. Overall postoperative ROM (95% CI: 3.27 to 11.92; P

Air-core high-temperature superconducting quadrupole magnets (AHQMs) differ from conventional iron-core quadrupole magnets, in that their iron cores are removed, and instead high-temperature superconductors (HTSs) are applied. The high operating temperature and high thermal stability of HTS magnets can improve their thermodynamic cooling efficiency. Thus, HTS magnets are more suitable than low temperature superconducting magnets for withstanding radiation and high heat loads in the hot cells of accelerators. AHQMs are advantageous because they are compact, light, and free from the hysteresis of ferromagnetic materials, due to the removal of the iron-core. To verify the feasibility of the use of AHQMs, we designed and fabricated a 3.0 T/m AHQM. The magnetic field properties of the fabricated AHQM were evaluated. Additionally, the characteristics of the air-core model and iron-core model of 9.0 T/m were compared in the scale for practical operation. In comparison with the iron-core model, AHQM significantly reduces the critical current (IC) due to the strong magnetic field inside the coil. In this study, a method for the accurate calculation of IC is introduced, and the calculated results are compared with measured results. Furthermore, the optimal shape design of the AHQM to increase the critical current is introduced.

A flux pump is one possible way to reduce the heat load of a superconducting magnet system by replacing mechanical connections with magnetic coupling. However, the heat loss of the flux pump should be analyzed so that it can be applied to conduction-cooled magnets because of the low temperature margin in conduction-cooled systems. In this paper, the simplified thermodynamic behavior of a linear-type flux pump system is investigated. The system is assumed to be cooled by a conduction cooling system. The heat generation of a linear-type flux pump is calculated based on the ac loss theory. The temperature stability of a thermal link for the flux pump system is analyzed with different design parameters. A design method is suggested for the thermal conductivity of the thermal link in a flux pump of conduction-cooled magnet by summarizing the results of the analysis.

Our research team has been developing a wireless power charging (WPC) system for electric vehicle (EV) using superconducting and normal conducting resonance coils in order to improve the transfer efficiency and stability. In the practical approach, the EV, which is installed outside, is wirelessly charged without moving. The antenna (Tx) coil is disclosed by rain or snow and so on. From this reason, the transfer characteristics surrounded by water circumstance, i.e., fresh water or salt water, should be evaluated to commercialize In addition, the high-voltage WPC system generates strong electromagnetic fields (EMFs) around Tx and receiver (Rx) coils. As the human safety with respect to EMFs is an important measure, it is required to identify the condition under which human exposure complies with the safety regulations. Thus, in this paper, as a fundamental approach, the spatial spots of current around Tx and Rx coils were measured. As well as, the transfer efficiencies of a WPC unit under different water circumstances of Tx and Rx coil were measured with an RF generator of power of 150 W, 370 kHz.

This paper reports the effects of a current sweep cycle method on reducing the screening current induced field (SCF) in a (RE)Ba2Cu3Ox (REBCO) coil. The screening current induced field in a REBCO coil causes two major problems: temporal magnetic field drift and a reduction of the central magnetic field. This is a critical problem in relation to REBCO coils, which require a homogeneous and stable magnetic field, during, for instance, nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) applications (Itoh et al., 2013; Hemmi et al., 2005; Hahn et al., 2008; Amemiya et al., 2008; Otsuka et al., 2011; Yang et al., 2013; Ahn et al., 2009; Koyama et al., 2009; Kajikawa et al., 2015). In an effort to circumvent the SCF problem, the current sweep cycle method is investigated based on experiments in this study. The experimental results show that a greater SCF reduction in a REBCO coil can be obtained by increasing the overshooting of the current sweep cycle.

This paper deals with the electrical characteristics of no-insulation coil wound with surface-processed HTS tape. The bypassing current path through turn-to-turn contacts within a coil is formed in the no-insulation coil, and this bypassing current path determines two characteristics: 1) self-protection and 2) charge-discharge delay. The amplitude of bypassing current is determined by contact resistance between the turn-to-turn contacts of the no-insulation coil. The surface roughness of the HTS tape is one of the parameters to change the contact resistance. The HTS tapes were processed to roughen by bead blast and abrasive paper, and the no-insulation coil is fabricated using processed HTS tape. We have studied the charge-discharge delay and self-protecting characteristic of each no-insulation coil by 1) sudden discharge tests and 2) overcurrent tests. The FEM simulations of contact resistance of no-insulation coil were carried out. The contact surface resistance of a case processed by abrasive paper has almost three times larger than that of reference no-insulation coil, and a case processed by bead blast presents almost same contact surface resistance with reference no-insulation coil.

A current lead is a connecting device between the superconducting magnet and the power supply. A large amount of heat transfer ocurrs through the current lead because the cold-end in a superconducting system is thermally linked with the warm-end part. Therefore, high-Tc superconductor (HTS) is used in the current lead for a tokamak system. However, it is hard to consider the dependance of HTS's critical current with respect to temperature because the conventional HTS current leads consist of the HTS tapes with the same width and thickness, and their critical currents can differ from their temperature. For this reason, cold-end of the HTS section in current lead is designed excessively than necessary specifications. This generates the additional heat transfer between cold-end and warm-end within the HTS current lead. In this paper, a study on the HTS current leads with asymmetric structure is conducted to reduce the heat transfer by reducing the cross-sectional area of the HTS current lead. Asymmetric current leads are fabricated considering the design parameters about heat transfer within the HTS current lead. Current transporting tests on the conventional, symmetrical, and asymmetrical HTS current leads are performed to confirm the feasibility of the suggested design. And then, heat load of the asymmetric current lead is compared with the symmetric current lead. From this study, it is found that heat load of the current lead is reduced by using the asymmetric HTS current lead.

In light of recent developments in genomic technology and the rapid accumulation of genomic information, a major transition toward precision medicine is anticipated. However, the clinical applications of genomic information remain limited. This lag can be attributed to several complex factors, including the knowledge gap between medical experts and bioinformaticians, the distance between bioinformatics workflows and clinical practice, and the unique characteristics of genomic data, which can make interpretation difficult. Here we present a novel genomic data model that allows for more interactive support in clinical decision-making. Informational modelling was used as a basis to design a communication scheme between sophisticated bioinformatics predictions and the representative data relevant to a clinical decision. This study was conducted by a multidisciplinary working group who carried out clinico-genomic workflow analysis and attribute extraction, through Failure Mode and Effects Analysis (FMEA). Based on those results, a clinical genome data model (cGDM) was developed with 8 entities and 46 attributes. The cGDM integrates reliability-related factors that enable clinicians to access the reliability problem of each individual genetic test result as clinical evidence. The proposed cGDM provides a data-layer infrastructure supporting the intellectual interplay between medical experts and informed decision-making.

AI assistants have found their place in households but most of the existing assistants use single modal interaction. We present a language assistant for kids called Hola (Hang out with the Language Assistant) which is a true multimodal assistant. Hola is a small mobile robot based assistant capable of understanding the objects around it and responding to questions about objects that it can see. Hola is also able to adjust the camera position and its own position to make an extra attempt to understand the object using robot control mechanism. The technology behind it uses a combination of natural language understanding, object detection, and hand pose detection. In addition, Hola also supports reading book in the form of storytelling for kids using OCR. Children can ask a question about any word that they do not understand and Hola can retrieve the information from the internet and tells the meaning, other details of the word. After reading the book or a page, the robot asks the child based on the words used in the book to confirm the child’s understanding of the book.

Recently, production technique and property of the High-Temperature Superconductor (HTS) tape have been improved. Thus, the study on applying an HTS magnet to the high magnetic field application is rapidly increased. A Nuclear Magnetic Resonance (NMR) spectrometer requires high magnitude and homogeneous of central magnetic field. However, the HTS magnet has fabrication errors because shape of HTS is tape and HTS magnet is manufactured by winding HTS tape to the bobbin. The fabrication errors are winding error, bobbin diameter error, spacer thickness error and so on. The winding error occurs when HTS tape is departed from the arranged position on the bobbin. The bobbin diameter and spacer thickness error occur since the diameter of bobbin and spacer are inaccurate. These errors lead magnitude and homogeneity of central magnetic field to be different from its ideal design. The purpose of this paper is to investigate the effect of winding error, bobbin diameter error and spacer thickness error on the central field and field homogeneity of HTS magnet using the virtual NMR signals in MATLAB simulation.

A prototype of the toroidal field (TF) secondary quench detection (SQD) system was developed and implemented with the Korea Superconducting Tokamak Advanced Research (KSTAR) device to carry out the design verification of the SQD. The SQD can detect a quench based on the change of absolute pressures (APs) and mass flow rates of helium in the cooling lines of the TF coils. If the primary quench detection system of the TF coils cannot detect a quench or the fast discharge of the TF coils cannot be carried out as planned, SQD should work to prevent the TF coils and the peripheral structures from severe damages. In addition, SQD should operate in the reliable and stable condition against the disturbances caused by the poloidal field coil discharge, plasma perturbation, and any faults of subsystems of the KSTAR device. The 2-out-of-3 (2oo3) voting configuration was applied to the SQD to enhance the reliability and stability of quench detection. The prototype SQD consists of AP and differential pressure transducers, signal interfaces, logic solvers, and interlock systems. All the transducers were selected from metallic types with no electronic circuit in order to reduce the failure rates caused by strong electromagnetic field and radiation around the tokamak. The transducers were installed in the manifolds of the helium inlet lines of the KSTAR TF coils. Their signals were amplified and compared with the reference voltage for quench decision in the signal interface unit. The quench signal generated by the signal interface unit was transmitted to the 2oo3 voting modules of the logic solvers. The design requirements of SQD were verified through testing the prototype SQD in the 2014 KSTAR campaign.

In this paper, characteristics of a thermally and magnetically triggered switch for a high-Tc superconducting (HTS) power converting system are experimentally analyzed. For verifying the efficiency of the suggested switch, current charging and discharging tests using heater-triggered switch with or without an external magnetic field are performed. Charging tests are performed with two charging sequences, i.e., CS1 and CS2. Each sequence is experimented with two kinds of heater currents to maintain different temperatures. Saturation current and saturation time are detected to calculate the pumping rate. Two discharging sequences, i.e., DS1 and DS2, are used for discharging tests with heater current to maintain 120 K. From the results, normalized load energies are calculated and compared.

The field stability of a no-insulation and a turn-to-turn soldered high-temperature superconducting (HTS) magnet is analyzed under sinusoidal noise operation. The stability of the magnetic field is a critical factor for some applications such as nuclear magnetic resonance (NMR) spectrometer. The no-insulation and turn-to-turn soldered HTS magnets have intrinsic residual resistance which acts like a low-pass filter attached to the main magnet. The intrinsic low-pass filter can improve the time stability of the magnetic field by reducing ac noises generated by the power supply. In this paper, the improved field stability is analyzed with a no-insulation and a turn-to-turn soldered HTS magnet sample. The sample magnets are operated under sinusoidal power supply noise. Qualitative analysis is conducted by simulating the virtual NMR lineshapes based on the field mapping results obtained during sample magnet operation. Both the no-insulation and turn-to-turn soldered magnets demonstrated improved field stability, but the field stability in the turn-to-turn soldered case is greater.

Flux diverters made of ferromagnetic materials can be used in high-temperature superconducting (HTS) magnets to change the magnetic field distribution and increase the critical current of the magnet. In this paper, the notch-shaped flux diverter increases the critical current of the HTS magnet by detouring the magnetic flux more effectively than the flat surface-shaped (simple) flux diverter. Numerical analyses are carried out to calculate the critical current using the simple-shaped and the notch-shaped flux diverters. Then, experiments are conducted to verify the results of the numerical analyses. As a result, the HTS coil with a notch-shaped flux diverter shows the increased critical current.

This paper deals with the effect of magnetic flux diverters on the current decay behaviors of high-temperature superconducting (HTS) coils which operate in semipersistent current mode (PCM) under alternating magnetic field. In superconducting synchronous machines, the HTS field coil can be designed to operate in PCM to obtain a steady magnetic field during operation. Due to the alternating magnetic field from the armature winding, the HTS field winding experiences an external magnetic field. As a result, the additional magnetization ac loss in the field coil would be induced, and it affects the current decay characteristics. In order to improve the current decay behavior of the HTS field coil, the use of flux diverter made of magnetic material can be considered. In this paper, we experimentally investigated the current decay characteristics of HTS field coils with magnetic flux diverters under alternating magnetic field. The measurement setup, which is composed of HTS field coil and armature coil, was fabricated. The measurement test of the current decay on the HTS field coil in PCM operation was carried out as functions of the amplitude and frequency of the armature coil.

We present results—cool-down, energization, and persistent-mode operation—of a solid-nitrogen (SN2)-cooled, magnesium diboride (MgB2) small-scale test coil. The test coil, immersed in a volume of solid nitrogen at 6 K, successfully operated in persistent-mode at 108 A for a period of 5 d. Although designated a ‘persistent-mode’ coil, its center field was measured to decay at a rate of −1, which is still considered low enough to meet the temporal stability requirement of −1, for most magnetic resonance imaging magnets. This decay rate translates to a calculated circuit resistance of –12 Ω, which is mainly from one MgB2-MgB2 joint in the circuit. However, when the coil temperature increased from 6 to 16 K, the field had dropped by 0.33%: we believe this was caused by the change of magnetization in the MgB2 superconductor, which in turn decreased a screening-current field (SCF) at the magnet center. We performed a finite element analysis with a simplified numerical model based on H formulation to verify whether magnetization-induced SCF is responsible for this 0.33% drop. Indeed, the model shows that the change of magnetization, i.e. screening-current reduction and current density redistribution, happens during temperature-cycle-induced Jc (T) variation, and thus affects the center magnetic field. However, the Jc (T) variation in the 2nd cycle had little effect on MgB2 magnetization and thus had negligible magnetic field change.

Ewing sarcoma (ES) as a primary intracranial tumor is very rare. Recently, CNS embryonal tumors with ES-like genomic change have been reported. Patients and methods We report a case of intracranial Ewing sarcoma in a 13-year-old girl who complained of headache and migraine. The tumor had developed in the right middle cranial fossa with a mass effect on the brain with impending transuncal herniation. Undifferentiated small round cell morphology with completely negative results for friend leukemia integration 1 transcription factor (Fli-1) and a nonspecific cytoplasmic CD99-positive staining pattern mislead the diagnosis as central nervous system (CNS) embryonal tumor, NOS. However, whole genome sequencing (WGS) revealed Ewing sarcoma (EWS)-Fli-1 gene fusion, which was confirmed by fluorescence in situ hybridization study and the diagnosis was revised to ES. This case is a true intracranial but extra-axial ES confirmed by WGS. We report this case of intracranial ES to demonstrate the importance of marker gene studies using FISH or NGS.

c2015 The Korean Fiber Society Abstract: Improvements of the UV-aging resistance of poly(p-phenylene benzobisoxazole) (PBO) filament yarns, spun yarns, and woven fabrics have been investigated after surface treatment in a continuous process by using polyurethane resin and UV-absorbing and/or UV-stabilizing agents. The UV-aging resistance of PBO specimens was evaluated by tensile strength and reduction rate measurements after exposing the samples to an M400 UV lamp and solar light. A mixture of UV-absorbing (Chiguard® 234) and UV-stabilizing (Chiguard 944) agents was found to be more effective compared to individual agents for improving the UV-aging resistance of PBO.

Critical current of high-temperature superconducting (HTS) coil is influenced by its own self magnetic field. Direction and density distribution of the magnetic field around the coil are fixed after the shape of the coil is decided. If the entire part of the HTS tape has homogeneous I c distribution characteristic, quench would be initiatedin fixed location on the coil. However, the actual HTS tape has in homogeneous I c distribution along the length. If the I c distribution of the HTS tape is known, we can expect the spot within the HTS coil that has the highest probability to initiate the quench. In this paper, I c distribution within the HTS coil under self-field effect is simulated by MATLAB. In the simulation procedure, I c distribution of the entire part of the HTS tape is assumed to follow Gaussian-distribution by central limit theorem. The HTS coil model is divided into several segments, and the critical current of each segment is calculated based on the-generalized Kim model. Single pancake model is simulated and self-field of HTS coil is calculated by Biot-Savart’s law. As a result of simulation, quench-initiating spot in the actual HTS coil can be predicted statistically. And that statistical analysis can help detect or protect the quench of the HTS coil.