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This paper presents a practical low-power, low-frequency magnetic induction (MI) transceiver based on symmetrical gaped two-loop antennas with an empirical circuit model for wireless underground communication. Because of the quasi-two-dimensional loop antennas for the transmitter (Tx) and the receiver (Rx), the tailored hardware platform is not only simple, but can be readily extended to a mutually orthogonal 3-D scheme. Through a mixed model of actual measurement data and theoretical parameters, we developed the two-loop antenna with the space of the antenna radius optimized for energy efficiency. The Tx power almost doubles that of the single Tx one, which provides channel expansion as well as system stability in terms of the Tx current level. Accordingly, the Rx signal is considerably increased by 9.5 dB in contrast with a typical single-Tx single-Rx configuration. Moreover, we used empirical-based modeling for a reliable electrical model. The empirical mutual inductance, which was modeled in a 25 m corridor, resulted in a channel correction factor of 0.86, showing that the signal intensity was reduced by 14% in the underground corridor compared to the free space. A maximum range of 68 m under a SNR of 9.5 dB and a path loss of 100.7 dB on a load of $50~\Omega $ at 34.5 dBm were predicted from the model. In addition, this study confirmed the system feasibility by a SNR of 8.7 dB in a practical lossy environment between two floors, where its value was converted into a MI channel at a distance of 70 m in the underground corridor.

Thermotherapy is a medical treatment based on the specific lesion exposure to high temperature. In the case of therapeutic levels of hyperthermia, moderately elevated temperature to a supra-physiological level (typically $43^{\circ}\mathrm{C}-45^{\circ}\mathrm{C})$ provides effect of cellular cytotoxicity that causes tumor necrosis. For many musculoskeletal disorders, the moderately elevated temperature could be useful for the treatment of pathology. The mild thermotherapy provides physiological benefits as increasing blood flow and pain relief [1].

FPGA (Field-Programmable Gate Array) has received much attention from nuclear industry as an alternative platform of PLC (Programmable Logic Controller)-based digital I&C (Instrumentation & Control). Software aspect of FPGA development encompasses several commercial tools such as logic synthesis and P&R (Place & Route), which should be first dedicated in accordance with domestic standards based on EPRI NP-5652. Even if a state-of-the-art supplementary EPRI TR-1025243 makes an effort, the dedication of indirect COTS (Commercial Off-The-Shelf) SW such as FPGA logic synthesis tools has still caused a dispute. This paper proposes an acceptance process and evaluation criteria, specific to COTS SW, not commercial-grade direct items. It specifically incorporates indirect COTS SW and also provides categorized evaluation criteria for acceptance. It provides an explicit linkage between acceptance methods (Verification and Validation techniques) and evaluation criteria, too. We tried to perform the evaluation and acceptance process upon a commercial FPGA logic synthesis tool being used to develop a new FPGA-based digital I&C in Korea, and could confirm its applicability.

A study on temperature stabilization effect of the immersion liquid in a 3-6 GHz microwave tomography (MT) system for medical diagnosis is presented. The designed temperature control device unit is applied in the MT system for the analysis of the temperature impact. This control unit with an advanced control method is required to precisely maintain the temperature of the immersion liquid for obtaining stable measurement data. If the temperature of the liquid is maintained ideally, the peak to peak deviation of the measured amplitude and phase are very small within approximately 0.18 dB and 1.3 degree over the entire frequency range. The temperature variation of the liquid is a key factor for high spatial resolution to detect small tumors. The detailed results are presented and discussed. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:461–464, 2016

This paper presents an experimental measurement system for 3?6 GHz microwave tomography (MT) of the breast. The measurement system is constructed as a minimal test bed to verify key components such as the sensing antennas, radio frequency (RF) transceiver, sensing mechanism, and image reconstruction method for our advanced MT system detecting breast cancer at an early stage. The test bed has eight RF channels operating at 3 to 6 GHz for high spatial resolution and a two-axis scanning mechanism for three-dimensional measurement. The measurement results from the test bed are shown and discussed.

This article presents the image reconstruction results of measurement data from a preliminary test using the first-developed precision microwave tomography (MT) system operating at 3–6 GHz for medical diagnosis. A simple phantom is used in the MT system to verify the data validation. The measurement dataset has very different patterns owing to the significant contrast of dielectric properties according to the existence of a phantom in the sensing area of the illumination tank at microwave frequencies. Thus, it is possible to obtain the image reconstruction from this measurement data. The detailed results are presented and discussed. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2445–2448, 2015

In this paper, we introduce an automatic phase calibration loop circuit for a focused microwave thermotherapy system for those with diseases of the leg. An extended time reversal method is also introduced. The loop circuit is evaluated by measuring the phase errors at the array antenna feeding port. These measurements are compared to those without a loop. The results show that the overall phase errors are reduced enough to focus fields at a target point.

This paper presents a study of the microwave energy localization for pathologic treatment of the knee in human tissue. For the computational study, we have developed the finite difference time domain (FDTD) electromagnetic (EM) solver and FDTD thermal solver. The simulation test using these solver was performed for a 2D knee model with the tumor at 915 MHz. The time reversal (TR) algorithm was proposed the effective beam focusing at the target position. The detailed results are presented and discussed.

In this paper, a transmission array of a focused microwave thermotherapy system is introduced for those with diseases of the leg. A microwave time reversal analysis is introduced to understand microwave focusing. The transmitter circuit of a transmission array is evaluated by measuring the phase control and the magnitude control at the array output port. The results are satisfied to focus fields at a target point.

Compact printed ultrawideband (UWB) antennas with triple band-notched characteristic are proposed. The designed antennas consist of a rectangular shaped patch, complementary meander line split ring resonators (CMLSRRs), and a spiral resonator are inserted in the radiation patch, feed line, and ground plane aimed at WiMAX band, WLAN 5 GHz, and ITU 8 GHz. Therefore, techniques of their antennas can be solved the interference between UWB systems and other wireless systems. All of antennas achieved a wide bandwidth of UWB frequency range for VSWR less than 2, except for triple notched-bands. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2265–2269, 2013

In this paper, we designed and implemented the planar monopole antenna using the coupling effect for the multi-band characteristic. A parasitic element for the multi-band characteristic based on a rectangular patch with single resonance is inserted. Spiral shaped parasitic element is used for minimizing the antenna size and obtaining the multi-resonance characteristic. The frequency characteristics are modified and optimized by varying specific parameters. By inserting an L-shaped resonator at both sides of the feed line which connected through the via hole to the ground plane, unnecessary frequency bands are eliminated. Proposed antenna dimension is . It is fabricated on the FR-4 substrate(

In this paper, a triple band-notched UWB antennas using a spiral resonator and a complementary split ring resonator is proposed as two types. The band-rejection characteristic of the designed antenna is analyzed through the structure and equivalent circuit model of spiral resonator and CSRR. The measured results of first type antenna show that a VSWR less than 2 was satisfied with a resonant frequency in the range of 1.16~12 GHz and it can be obtained the band-stop performance at 3.3~3.85 GHz, 5.15~6.1 GHz, and 8.025~8.5 GHz. The measured results of second type antenna show that a VSWR less than 2 was satisfied with this antenna works from 1.79 to 12 GHz and it can be achieved the band-notched performance at 3.3~3.88 GHz, 5.12~5.94 GHz, and 8.025~8.51 GHz. Through the measured results, the designed antenna was satisfied UWB band except for triple notched bands.

In this paper, a broadband antenna of the CPW structure with a band-notched characteristic is presented. To obtain this characteristic, the complementary split ring resonator(CSRR) is inserted in the ground plane. In addition, the IEEE 802.11a WLAN band(5.15～5.825 GHz) appears in the band-notched characteristic. The proposed antenna dimension is , and it is designed on the FR-4 substrate having a relative dielectric constant of 4.4. The designed antenna shows that the resonant frequency is 2.03～10.78 GHz below the return loss of -10 dB and a VSWR less than 2 was satisfied. As a result, the proposed CSRR has a band-notched characteristic in the range of 4.917～6.017 GHz which the center frequency is about 5.4 GHz band.

Introduction Several recent studies have investigated the changes of multifidus muscles in patients with chronic neck pain. Also, the longus coli muscle, one of the deep cervical flexor muscles, showed smaller cross sectional area (CSA) in patients with chronic neck pain in comparison with healthy people. To our knowledge, there is no study investigating the association between morphological features of cervical paravertebral muscles in electrodiagnosed cervical radiculopathy patients. In this study, we investigate the change in CSA and composition of the cervical flexor and multifidus muscles using the digital data from MRIs of patients with electrodiagnosed cervical radiculopathy. Methods Twenty-four patients with unilateral cervical radicular pain who had cervical MRI and EMG examinations between 1 January 2015 and 2016 were retrospectively analysed. The inclusion criteria were as follows: (1) patients with the symptoms of unilateral cervical pain or referral to one upper limb, (2) diagnosis of cervical radiculopathy in EMG. Exclusion criteria included: (1) a history of cervical surgery; (2) a history of spinal fracture or injuries; (3) primary or metastatic spinal tumor. Axial slice at the level of C4-5 mid disc level image was selected to calculate the muscle CSA, with their maximal CSAs. Total CSA and functional CSA measurements of the bilateral longus colli, sternocleidomastoid and multifidus muscles were measured by using Image J (version 1.43, National Institutes of Health, Bethesda, Maryland). All muscle measurements were acquired by one investigators. Functional CSA measurement was obtained by using threshold method (including only pixels within lean muscle tissue range). Statistical analysis was performed using SPSS® v. 15. Results The baseline characteristics of the study participants are shown in Table 1. There was no significant difference in total CSA in longus colli, sternocleidomastoid and multifidus muscles between involved and uninvolved groups. Data analysis showed significant difference between the functional CSA of the lognus colli muscle the involved/uninvolved sides (Table 2). Also, there is significant difference in the ratio of longus colli musle (functional longus colli muscle CSA/total longus colli muscle CSA) between the involved and uninvolved sides (P Conclusion This is the study to show via MRI assessment that patients with cervical radiculopathy have smaller ipsilateral functional CSA of the longus colli muscle LCM in comparison with uninvolved side. Consideration of these muscles in MRI could be helpful in the diagnosis and prognosis of cervical radiculopathy.

Introduction Deep branch of the ulnar nerve (DBUN) study using ultrasound has just begun with the development of high-resolution ultrasound (HRUS) technology. In this study, we would like to present the safe-zone data that can be used to accurately locate the DBUN using HRUS. So it could be used as reference for various procedures such as acupuncture and botox injection. Methods We performed HRUS with high-frequency probes (5–12 MHz). In both hands of 10 healthy volunteers (n = 20), the cross-sectional area (CSA) was measured at medial side of the hook of the hamate bone. Depth from the skin and distance from the tip of the hook of the hamate were also measured. Same data were measured from 1 patient who was diagnosed as DBUN neuropathy which was confirmed by electromyography study. Results DBUN was clearly observed in the medial wall of the hook of the hamate bone in all subjects. The mean CSA value of healthy volunteers was 1.4 ± 0.2 mm 2 , the depth from the skin was 7.4 ± 1.1 mm, and the distance from the tip of the hook of the hamate bone was 6.0 ± 0.8 mm. The depth from the skin of DBUN neuropathy patient was 9.6 mm and the distance from the hook of the hamate was 7.1 mm, which was not significantly different from healthy volunteers, but CSA was significantly increased to 2.9 mm 2 . Conclusion This study provides data that can predict the location of the DBUN, which will help avoid complications when performing various injection procedures on the hand. In addition, HRUS could be helpful for diagnosis of DBUN neuropathy.

We propose a novel configuration of a triple band-notched ultra-wideband (UWB) antenna. The designed structure is based on an elliptical monopole antenna combined with a complementary split ring resonator (CSRR) structure and a spiral resonator. The spiral resonator can achieve the dual-band notched performance at WiMAX band and ITU 8 GHz by adjusting the length and width of a spiral line. Besides, the CSRR can obtain the notched band at WLAN 5 GHz by changing the radius of a ring slot. The designed antenna shows that a VSWR of less than 2 was satisfied with a resonant frequency in the range of 1.34–11.4 GHz with a 78.96%, except for triple notched bands. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:4–6, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27275

A sensing probe for medical imaging diagnostic systems is presented. The proposed probe consists of a double-ridged waveguide (DRWG) filled with dielectric ceramic and an aperture with a tapered ridge. The DRWG is used to suppress higher-order mode radiations in the rectangular waveguide. The proposed probe is designed for broadband sensing in an immersion liquid with a complex dielectric constant. The performance of the fabricated probe successfully covers the frequency band of 3-6 GHz. The probe suppresses higher-order modes and provides symmetric and similar radiation patterns within the operating frequency range.

A real-time operating system (RTOS) is an Operating System (OS) intended for real-time applications. Benchmarking is a point of reference by which something can be measured. AQNX is a kind of RTOS developed by QSSL (QNX Software Systems Ltd.) in Canada. ELMSYS is the brand name of a commercially available Personal Computer (PC) for such applications as Cabinet Operator Module (COM) of a Digital Plant Protection System (DPPS) and COM of a Digital Engineered Safety Features Actuation System (DESFAS). ELMSYS PC hardware is undergoing qualification procedure by KTL (Korea Testing Lab.) for use as a Cabinet Operator Module (COM). The QNX RTOS dedication is being researched by Korea Atomic Energy Research Institute (KAERI). This paper describes the outline and benchmarking test results of Priority Inversion, Deadlock, Context Switching, Message Passing, Synchronization and Deadline Violation of QNX RTOS under an ELMSYS PC platform.

In the Korea Nuclear instrumentation and control (I&C) System (KNICS) project, a digital safety system including Reactor Protection System (RPS) and Engineered Safety Features-Component Control System (ESF-CCS) is developed. It is based on a safety grade Programmable Logic Controller (PLC) as a platform for the safety critical I&C systems. The software used in the digital safety system is classified as safety-critical, and it is qualified according to an appropriate lifecycle. This lifecycle includes design and qualification activities for the components and the system. In the KNICS project a defense-in-depth organizational structure for qualification is implemented based on different teams including 3rd party review teams. Each team uses diverse techniques, methods, and tools for their qualification tasks. Using the Korean KNICS project as an example, the results of Defence-in-Depth and Diversity (D3) qualification of safety-critical software are presented.

In this paper, it is focus on the group delay of BBA (Base Band Analog) filter and IF transceiver module for wireless ATM (Asynchronous Transfer Mode). In order to improve the group delay, the singly equalized form of BBA filter is adapted. In the case of IF transceiver module, the response characteristic of 3 dB ripple and the IMD characteristic of -50 dBc are measured. The measurement result doesn't match the specification of IF transceiver (ripple is 1 dB and IMD is -60 dBc), at first, the reason is, however, discussed. Two method will be suggested in order to improve the response characteristic of IF transceiver.