• Title/Summary/Keyword: radiofrequency

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The Electromagnetic Fields, Exposure Limits and Regulations (긴급제언: 전자파 환경, 인체보호기준과 규제 -세계보건기구(WHO) 휴대폰, 무선주파수를 발암가능물질(2B)로 분류-)

  • Moon, Hank
    • Journal of the Korean Professional Engineers Association
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    • v.44 no.5
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    • pp.31-35
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    • 2011
  • The WHO/International Agency for Research on Cancer(IARC) has classified radiofrequency electromagnetic fields as possibly carcinogenic to humans(Group 2B), based on an increased risk for glioma, a malignant type of brain cancer, associated with wireless phone use on 31, May 2011. It takes 10 years after announcing the electric magnetic as possibly carcinogenic to humans(Group 2B) and 14 years after starting research project. It is too late as mentioned, too weak in terms of the same class to 'pickles & coffee' and too little in terms of using words 'more studies required'. The guidelines on human exposure to electromagnetic fields have been developed to provide guidance to identify the safety of exposure to electromagnetic fields. On the recent recommendations of safety guidelines, there has been discussion on possible chronic effects of electromagnetic fields with much lower or no threshold. This paper riviews the global trends of safety guidelines and has suggested the new guidelines for protecting the human health, wildlife and insects.

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Model of dynamic clustering-based energy-efficient data filtering for mobile RFID networks

  • Vo, Viet Minh Nhat;Le, Van Hoa
    • 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.

Stereoelectroencephalography in Pediatric Epilepsy Surgery

  • Tomlinson, Samuel B.;Buch, Vivek P.;Armstrong, Dallas;Kennedy, Benjamin C.
    • Journal of Korean Neurosurgical Society
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    • v.62 no.3
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    • pp.302-312
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    • 2019
  • Stereoelectroencephalography (SEEG) is an invasive technique used during the surgical management of medically refractory epilepsy. The utility of SEEG rests in its ability to survey the three-dimensional organization of the epileptogenic zone as well as nearby eloquent cortices. Once concentrated to specialized centers in Europe and Canada, the SEEG methodology has gained worldwide popularity due to its favorable morbidity profile, superior coverage of deep structures, and ability to perform multi-lobar explorations without the need for craniotomy. This rapid shift in practice represents both a challenge and an opportunity for pediatric neurosurgeons familiar with the subdural grid approach. The purpose of this review is to discuss the indications, technique, and safety of long-term SEEG monitoring in children. In addition to reviewing the conceptual and technical points of the diagnostic evaluation, attention will also be given to SEEG-based interventions (e.g., radiofrequency thermo-coagulation).

Current status of stereotactic body radiotherapy for the treatment of hepatocellular carcinoma

  • Park, Jongmoo;Park, Jae Won;Kang, Min Kyu
    • Journal of Yeungnam Medical Science
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    • v.36 no.3
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    • pp.192-200
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    • 2019
  • Stereotactic body radiotherapy (SBRT) is an advanced form of radiotherapy (RT) with a growing interest on its application in the treatment of hepatocellular carcinoma (HCC). It can deliver ablative radiation doses to tumors in a few fractions without excessive doses to normal tissues, with the help of advanced modern RT and imaging technologies. Currently, SBRT is recommended as an alternative to curative treatments, such as surgery and radiofrequency ablation. This review discusses the current status of SBRT to aid in the decision making on how it is incorporated into the HCC management.

Mini Review: A Current Status of Microwave Susceptor Packaging (전자레인지 서셉터 패키징 기술개발 현황)

  • Lee, Wooseok;Choi, Jungwook;Song, Hyuk-Hwan;Ko, Seonghyuk
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.26 no.3
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    • pp.133-138
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    • 2020
  • As HMR (home meal replacement) food market grows rapidly, a new packaging with more HMR specialized functions is highly required to promote consumers' convenience. A susceptor is defined as a material generating heat by absorbing electromagnetic energy such typically as radiofrequency or microwave radiation. In microwave cooking, susceptors are made of conductive metal thin film deposited on paper or plastic sheet and have generally been used to help crispen or brown foods by converting microwave energy into heat. This mini review article deals with current status of microwave susceptor packaging including commercial products, technical theory, types of susceptor and a test method for heating performance.

Surface modification of materials by thermal plasma (열플라즈마를 이용한 재료의 표면개질)

  • Kang, Seong-Pyo;Lee, Han Jun;Kim, Tae-Hee
    • Journal of the Korean institute of surface engineering
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    • v.55 no.6
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    • pp.308-318
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    • 2022
  • The surface modification and treatment using thermal plasma were reviewed in academic fields. In general, thermal plasma is generated by direct current (DC) and radiofrequency (RF) power sources. Thermal spray coating, a typical commercial process using thermal plasma, is performed by DC thermal plasma, whereas other promising surface modifications have been reported and developed using RF thermal plasma. Beyond the thermal spray coating, physical and chemical surface modifications were attempted widely. Superhydrophobic surface treatment has a very high industrial demand particularly. Besides, RF thermal plasma system for large-area film surface treatment is being developed. Thermal plasma is especially suitable for the surface modification of low-dimensional nanomaterial (e.g., nanotubes) by utilizing high temperature and rapid quenching. It is able to synthesize and modify nanomaterials simultaneously in a one-pot process.

Percutaneous Procedures for Trigeminal Neuralgia

  • Chang, Kyung Won;Jung, Hyun Ho;Chang, Jin Woo
    • Journal of Korean Neurosurgical Society
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    • v.65 no.5
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    • pp.622-632
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    • 2022
  • Microvascular decompression is the gold standard for the treatment of trigeminal neuralgia (TN). However, percutaneous techniques still play a role in treating patients with TN and offer several important advantages and efficiency in obtaining immediate pain relief, which is also durable in a less invasive and safe manner. Patients' preference for a less invasive method can influence the procedure they will undergo. Neurovascular conflict is not always a prerequisite for patients with TN. In addition, recurrence and failure of the previous procedure can influence the decision to follow the treatment. Therefore, indications for percutaneous procedures for TN persist when patients experience idiopathic and episodic sharp shooting pain. In this review, we provide an overview of percutaneous procedures for TN and its outcome and complication.

Role of Radio Frequency Identification (RFID) in Warehouse and Logistic Management System using Machine Learning Algorithm

  • Laviza Falak Naz
    • 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 study of thermal change by chemoport in radiofrequency hyperthermia (고주파 온열치료시 케모포트의 열적 변화 연구)

  • Lee, seung hoon;Lee, sun young;Gim, yang soo;Kwak, Keun tak;Yang, myung sik;Cha, seok yong
    • The Journal of Korean Society for Radiation Therapy
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    • v.27 no.2
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    • pp.97-106
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    • 2015
  • Purpose : This study evaluate the thermal changes caused by use of the chemoport for drug administration and blood sampling during radiofrequency hyperthermia. Materials and Methods : 20cm size of the electrode radio frequency hyperthermia (EHY-2000, Oncotherm KFT, Hungary) was used. The materials of the chemoport in our hospital from currently being used therapy are plastics, metal-containing epoxy and titanium that were made of the diameter 20 cm, height 20 cm insertion of the self-made cylindrical Agar phantom to measure the temperature. Thermoscope(TM-100, Oncotherm Kft, Hungary) and Sim4Life (Ver2.0, Zurich, Switzerland) was compared to the actual measured temperature. Each of the electrode measurement position is the central axis and the central axis side 1.5 cm, 0 cm(surface), 0.5 cm, 1.8 cm, 2.8 cm in depth was respectively measured. The measured temperature is $24.5{\sim}25.5^{\circ}C$, humidity is 30% ~ 32%. In five-minute intervals to measure the output power of 100W, 60 min. Results : In the electrode central axis 2.8 cm depth, the maximum temperature of the case with the unused of the chemoport, plastic, epoxy and titanium were respectively $39.51^{\circ}C$, $39.11^{\circ}C$, $38.81^{\circ}C$, $40.64^{\circ}C$, simulated experimental data were $42.20^{\circ}C$, $41.50^{\circ}C$, $40.70^{\circ}C$, $42.50^{\circ}C$. And in the central axis electrode side 1.5 cm depth 2.8 cm, mesured data were $39.37^{\circ}C$, $39.32^{\circ}C$, $39.20^{\circ}C$, $39.46^{\circ}C$, the simulated experimental data were $42.00^{\circ}C$, $41.80^{\circ}C$, $41.20^{\circ}C$, $42.30^{\circ}C$. Conclusion : The thermal variations were caused by radiofrequency electromagnetic field surrounding the chemoport showed lower than in the case of unused in non-conductive plastic material and epoxy material, the titanum chemoport that made of conductor materials showed a slight differences. This is due to the metal contents in the chemoport and the geometry of the chemoport. And because it uses a low radio frequency bandwidth of the used equipment. That is, although use of the chemoport in this study do not significantly affect the surrounding tissue. That is, because the thermal change is insignificant, it is suggested that the hazard of the chemoport used in this study doesn't need to be considered.

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Results of radiofrequency catheter ablation in children and adolescent with tachyarrhythmia (소아 청소년 부정맥 환자에서 고주파 전극도자 절제술의 이용 성적)

  • Chang, Young Beom;Lee, Seung Hyun;Kang, Eun Young;Rhee, Kyoung-Suk;Joo, Chan Uhng
    • Clinical and Experimental Pediatrics
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    • v.50 no.11
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    • pp.1085-1090
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    • 2007
  • Purpose : Radiofrequency catheter ablation (RFCA) has become an effective therapeutic modality for treating pediatric tachyarrhythmias. Using conventional RFCA catheters, ablation of parahisian accessory pathways may be difficult and have high risk for heart block. We reviewed the efficacy and complications of the RFCA in children and adolescent with arrhythmias including parahisian accessory pathways. Methods : We studied 48 patients (aged 2 years to 20 years) who had undergone RFCA from August 2003 to March 2007. We reviewed clinical findings, electrophysiologic studies, RFCA data, complications, and follow-up results of the patients. Results : Mean age of the patients was 13.1 years. Numbers and types of arrhythmias (age, acute success rate) were as follows: 19 WPW syndrome including 5 parahisian accessory pathways ($13.7{\pm}4.6yr$, 18/19), 11 atrioventricular reentrant tachycardia with concealed bypass tract ($12.3{\pm}5.0yr$, 10/11), 13 atrioventricular nodal reentrant tachycardia ($12.6{\pm}4.4yr$, 13/13), 4 atrial flutter ($13.0{\pm}7.4yr$, 3/4), and 1 ventricular tachycardia (20 yr, 1/1). Associated cardiac structural lesion was not detected in 48 patients. The recurrence rate was 6.5%, and the final success rate was 93.8%. Conclusion : These results suggest that RFCA is a highly effective treatment method in children and adolescent with tachyarrhythmia.