• Journal of electromagnetic engineering and science
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• v.15 no.3
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• pp.173-180
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• 2015

To explore the effects of radiofrequency electromagnetic field on the fate of neuronal cells, we investigated whether exposure to 915 MHz radiofrequency identification (RFID) caused morphological changes in neuronal cells in rat hippocampal dentate gyrus (DG). A reverberation chamber was used as a whole-body RFID exposure system. Rats were assigned to two groups: sham- and RFID-exposed groups. Rats in the RFID-exposed group were exposed to RFID at 4 W/kg specific absorption rate (SAR) for 8 hours daily, 5 days per week, for 2 weeks. Morphological evaluation of DG was performed using immunohistochemistry with doublecortin (DCX) as a neuronal precursor cell marker and neuronal nuclei (NeuN) as a mature neuronal cell marker. No significant morphological changes in DCX+ or NeuN+ cells in the DG of RFID-exposed rats were observed. These results suggest that RFID exposure induces no significant change in DCX+ neuronal precursor or NeuN+ neuronal cells in DG of rats.

• The Korean Journal of Pain
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• v.29 no.2
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• pp.103-109
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• 2016

Background: The location and the number of lumbar sympathetic ganglia (LSG) vary between individuals. The aim of this study was to determine the appropriate level for a lumbar sympathetic ganglion block (LSGB), corresponding to the level at which the LSG principally aggregate. Methods: Seventy-four consecutive subjects, including 31 women and 31 men, underwent LSGB either on the left (n = 31) or the right side (n = 43). The primary site of needle entry was randomly selected at the L3 or L4 vertebra. A total of less than 1 ml of radio opaque dye with 4% lidocaine was injected, taking caution not to traverse beyond the level of one vertebral body. The procedure was considered responsive when the skin temperature increased by more than $1^{\circ}C$ within 5 minutes. Results: The median responsive level was significantly different between the left (lower third of the L4 body) and right (lower margin of the L3 body) sides (P = 0.021). However, there was no significant difference in the values between men and women. The overall median responsive level was the upper third of the L4 body. The mean responsive level did not correlate with height or BMI. There were no complications on short-term follow-up. Conclusions: Selection of the primary target in the left lower third of the L4 vertebral body and the right lower margin of the L3 vertebral body may reduce the number of needle insertions and the volume of agents used in conventional or neurolytic LSGB and radiofrequency thermocoagulation.

• ETRI Journal
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• v.38 no.5
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• pp.988-995
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• 2016

In this paper, we present a new specific and customized interface tool with parameter identification of Modified Butterworth-Van Dyke models for ladder bulk acoustic wave filters. The aforementioned tool is easy to use and flexible because it allows simulations and reengineering to be conducted in an application. A modular design approach is applied to simplify the extension of the proposed tool for different topologies. The proposed tool was validated using measurements from an aluminum-nitride based ladder BAW filter dedicated to the frequency ranges of the Universal Mobile Telecommunications Service and standards and Wideband Code Division Multiple Access.

• International Journal of Computer Science & Network Security
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• v.24 no.6
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• pp.109-118
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• 2024

The world today is advancing towards a digital solution for every indusial domain varying from advanced engineering and medicine to training and management. The supply cycles can only be boosted via an effective management of the warehouse and a stronger hold over the logistics and inventory insights. RFID technology has been an open source tool for various MNCs and corporal organization who have progressed along a considerable drift on the charts. RFID is a methodology of analysing the warehouse and logistic data and create useful information in line to the past trends and future forecasts. The method has a high tactical accuracy and has been seen providing up to 99.57% accurate insights for the future cycle, based on the organizational capabilities and available resources. This paper discusses the implementation of RFID on field and provides results of datasets retrieved from controlled data of a practical warehouse and logistics system.

• The Korean Journal of Pain
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• v.24 no.1
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• pp.48-52
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• 2011

Occipital neuralgia is usually defined as paroxysmal stabbing pain in the greater or lesser occipital nerve (GON or LON) distribution. In occipital neuralgia patients, surgical considerations are carefully taken into account if medical management is ineffective. However, identification of the occipital artery by palpation in patients with thick necks or small occipital arteries can be technically difficult. Therefore, we established a new technique using transcranial Doppler (TCD) sonography for more accurate and rapid identification. The patient was a 64-year-old man who had undergone C1-C3 screw fixation and presented with intractable stabbing pain in the bilateral GON and LON distributions. In cases in which pain management was performed using medication, physical therapy, nerve block, or radiofrequency thermocoagulation, substantial pain relief was not consistently achieved, and recurrence of pain was reported. Therefore, we performed occipital neurectomy of the bilateral GON and LON by using TCD sonography, which helped detect the greater occipital artery easily. After the operation, the patient’s headache disappeared gradually, although he had discontinued all medication except antidepressants. We believe that this new technique of occipital neurectomy via a small skin incision performed using TCD sonography is easy and reliable, has a short operative time, and provides rapid pain relief.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.786-787
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• 2006

The magnetic inductance of nanocrystalline $Fe_{73}Si_{16}B_7Nb_3Cu_1$ and an amorphous FeSiB powder sheet has been investigated to identify RFID performance. The powder was mixed with binder and solvent and tape-casted to form films. Results show annealing significantly influenced on the inductance of the material. The surface oxidation of the particles was the main reason for the reduced inductance. The maximum inductance of $Fe_{73}Si_{16}B_7Nb_3Cu_1$ alloy was about $88{\mu}H$ at 17.4 MHz, about 65% greater compared to the FeSiB alloy. The higher inductance in the nanocrystalline alloy indicates it may be used as a potential replacement of current RFID materials.

• ETRI Journal
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• v.43 no.3
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• pp.427-435
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• 2021

Data filtering is an essential task for improving the energy efficiency of radiofrequency identification (RFID) networks. Among various energy-efficient approaches, clustering-based data filtering is considered to be the most effective solution because data from cluster members can be filtered at cluster heads before being sent to base stations. However, this approach quickly depletes the energy of cluster heads. Furthermore, most previous studies have assumed that readers are fixed and interrogate mobile tags in a workspace. However, there are several applications in which readers are mobile and interrogate fixed tags in a specific area. This article proposes a model for dynamic clustering-based data filtering (DCDF) in mobile RFID networks, where mobile readers are re-clustered periodically and the cluster head role is rotated among the members of each cluster. Simulation results show that DCDF is effective in terms of balancing energy consumption among readers and prolonging the lifetime of the mobile RFID networks.

• Smart Structures and Systems
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• v.18 no.6
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• pp.1217-1231
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• 2016

In this research, a slotted patch antenna sensor is designed for wireless strain and crack sensing. An off-the-shelf RFID (radiofrequency identification) chip is adopted in the antenna sensor design for signal modulation. The operation power of the RFID chip is captured from wireless reader interrogation signal, so the sensor operation is completely battery-free (passive) and wireless. For strain and crack sensing of a structure, the antenna sensor is bonded on the structure surface like a regular strain gage. Since the antenna resonance frequency is directly related with antenna dimension, which deforms when strain occurs on the structural surface, the deformation/strain can be correlated with antenna resonance frequency shift measured by an RFID reader. The slotted patch antenna sensor performance is first evaluated through mechanics-electromagnetics coupled simulation. Extensive experiments are then conducted to validate the antenna sensor performance, including tensile and compressive strain sensing, wireless interrogation range, and fatigue crack sensing.

• Journal of Sensor Science and Technology
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• v.21 no.2
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• pp.103-108
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• 2012

Radiofrequency(RF) signal is a key medium to the most of the present wireless communication devices including RF identification devices(RFID) and smart sensors. However, the most critical barrier to overcome in RFID application is in the failure rate in detection. The most notable improvement in the detection was from the introduction of EPC Class1 Gen2 protocol, but the fundamental problems in the physical properties of the RF signal drew less attention. In this work, we focused on the physical properties of the RF signal in order to understand the failure rate by noting the existence of the ground planes and noise sources in the real environment. By using the mathematical computation software, Maple, we simulated the distribution of the electromagnetic field from a dipole antenna when ground planes exist. Calculations showed that the dark area can be formed by interference. We also constructed a test system to measure the failure rate in the detection of a RFID transponder. The test system was composed of a fixed RFID reader and an EPC Class1 Gen2 transponder which was attached to a scanner to sweep in the x-y plane. Labview software was used to control the x-y scanner and to acquire data. Tests in the laboratory environment showed that the dark area can be as much as 43 %. One who wants to use RFID and smart sensors should carefully consider the extent of the dark area.