• Title/Summary/Keyword: simultaneous

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Development of a Portable Detection System for Simultaneous Measurements of Neutrons and Gamma Rays (중성자선과 감마선 동시측정이 가능한 휴대용 계측시스템 개발에 관한 연구)

  • Kim, Hui-Gyeong;Hong, Yong-Ho;Jung, Young-Seok;Kim, Jae-Hyun;Park, Sooyeun
    • Journal of radiological science and technology
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    • v.43 no.6
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    • pp.481-487
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    • 2020
  • Radiation measurement technology has steadily improved and its usage is expanding in various industries such as nuclear medicine, security search, satellite, nondestructive testing, environmental industries and the domain of nuclear power plants (NPPs). Especially, the simultaneous measurements of gamma rays and neutrons can be even more critical for nuclear safety management of spent nuclear fuel and monitoring of the nuclear material. A semiconductor detector comprising cadmium, zinc, and tellurium (CZT) enables to detect gamma-rays due to the significant atomic weight of the elements via immediate neutron and gamma-ray detection. Semiconductor sensors might be used for nuclear safety management by monitoring nuclear materials and spent nuclear fuel with high spatial resolution as well as providing real-time measurements. We aim to introduce a portable nuclide-analysis device that enables the simultaneous measurements of neutrons and gamma rays using a CZT sensor. The detector has a high density and wide energy band gap, and thus exhibits highly sensitive physical characteristics and characteristics are required for performing neutron and gamma-ray detection. Portable nuclide-analysis device is used on NPP-decommissioning sites or the purpose of nuclear nonproliferation, it will rapidly detect the nuclear material and provide radioactive-material information. Eventually, portable nuclide-analysis device can reduce measurement time and economic costs by providing a basis for rational decision making.

Simultaneous resection of synchronous colorectal liver metastasis: Feasibility and development of a prediction model

  • Mufaddal Kazi;Shraddha Patkar;Prerak Patel;Aditya Kunte;Ashwin Desouza;Avanish Saklani;Mahesh Goel
    • Annals of Hepato-Biliary-Pancreatic Surgery
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    • v.27 no.1
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    • pp.40-48
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    • 2023
  • Backgrounds/Aims: Timing of resection for synchronous colorectal liver metastasis (CRLM) has been debated for decades. The aim of the present study was to assess the feasibility of simultaneous resection of CRLM in terms of major complications and develop a prediction model for safe resections. Methods: A retrospective single-center study of synchronous, resectable CRLM, operated between 2013 and 2021 was conducted. Upper limit of 95% confidence interval (CI) of major complications (≥ grade IIIA) was set at 40% as the safety threshold. Logistic regression was used to determine predictors of morbidity. Prediction model was internally validated by bootstrap estimates, Harrell's C-index, and correlation of predicted and observed estimates. Results: Ninety-two patients were operated. Of them, 41.3% had rectal cancers. Major hepatectomy (≥ 4 segments) was performed for 25 patients (27.2%). Major complications occurred in 20 patients (21.7%, 95% CI: 13.8%-31.5%). Predictors of complications were the presence of comorbidities and major hepatectomy (area under the ROC curve: 0.692). Unacceptable level of morbidity (≥ 40%) was encountered in patients with comorbidities who underwent major hepatectomy. Conclusions: Simultaneous bowel and CRLM resection appear to be safe. However, caution should be exercised when combining major liver resections with bowel resection in patients with comorbid conditions.

Periosteum-attached Autogenous Block Bone Graft with Simultaneous Implant Placement on the Anterior Maxilla: A Case Report

  • Seung-Hyun Park;Jongseung Kim;Ui-Won Jung;Jae-Kook Cha
    • Journal of Korean Dental Science
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    • v.17 no.2
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    • pp.64-74
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    • 2024
  • This case report presents the long-term radiographic outcomes of a novel approach for simultaneous lateral augmentation and implant surgery. A 60-year-old male patient who required tooth extraction of the maxillary central and lateral incisors due to trauma visited the clinic. After tooth extraction, severe horizontal and vertical deficiencies occurred owing to atrophy of the alveolar ridge, and a simultaneous guided bone regeneration (GBR) procedure was planned along with the installation of two implants. In the present case, a modification of the conventional 'sandwich technique' was used by placing the mixture of autogenous bone chips and xenografts at the outermost layer to maximize the osteogenic potential at the coronal part of augmentation while applying solely xenografts at the inner layer. To enhance volumetric stability, an autogenous block of periosteum harvested from the maxillary tuberosity was incorporated between the two layers. Cone-beam computed tomography was performed at baseline and 3 years after the surgery to compare radiographic outcomes. Dehiscence after fixture installation was successfully observed at the re-entry of the surgery site. Three years after the surgery, average horizontal bone gains of 6.11 mm and 4.12 mm were observed in the maxillary central and lateral incisor areas, respectively. Healthy peri-implant mucosa and well maintained marginal bone levels were observed 8 years after the surgery, meeting the criteria for implant success. The findings of this case suggest that a substantial amount of horizontal bone gain can be obtained with a layered approach using autogenous bone materials and xenografts, highlighting the advantages of incorporating autogenous blocks into the simultaneous GBR procedure.

Simultaneously evolutionary optimization of several natural frequencies of a two dimensional structure

  • Zhao, Chongbin;Steven, G.P.;Xie, Y.M.
    • Structural Engineering and Mechanics
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    • v.7 no.5
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    • pp.447-456
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    • 1999
  • This paper presents a solution method, which can be regarded as the further extension of the generalized evolutionary method (Zhao et al. 1998a), for the simultaneous optimization of several different natural frequencies of a structure in general and a two dimensional structure in particular. The main function of the present method is to optimize the topology of a structure so as to simultaneously make several different natural frequencies of interest to be of the corresponding different desired values for the target structure. In order to develop the present method, the new contribution factor of an element is proposed to consider the contribution of an element to the gaps between the currently calculated values for the different natural frequencies of interest and their corresponding desired values in a weighted manner. Using this new contribution factor of an element, the most inefficiently used material can be detected and removed gradually from the design domain of a structure. Through applying the present method to optimize two and three different natural frequencies of a two dimensional structure, it has been demonstrated that it is possible and applicable to use the generalized evolutionary method for tackling the simultaneous optimization of several different natural frequencies of a structure in the structural design.

Simultaneous observations of the H2O and SiO masers toward the late-type stars using KVN

  • Yun, Youngjoo;Cho, Se-Hyung;Kim, Jaeheon;Choi, Yoon Kyung
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.59.2-59.2
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    • 2015
  • We present the results of simultaneous observations of the H2O and SiO masers emitted from the circumstellar envelopes of the late-type stars. These observations have been carried out at the K and Q bands using KVN since 2014 August and were scheduled to test the feasibility of multi-frequency phase referencing analysis on the maser lines. In order to increase the accuracy of group delay solution in the fringe search on the continuum source, the IF channels were randomly distributed within the available bandwidth of 500 MHz in each band. The positions of all maser spots are relatively described with respect to the position of the reference continuum source through the source frequency phase referencing technique, and this provides the astrometric position accuracy. Therefore, the relative locations of the H2O maser spots with respect to the SiO maser spots are determined from our observations, and the capability of the simultaneous multi-band observation of KVN is proved to be powerful to study the maser pumping mechanism around the late-type stars.

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Simultaneous Analysis of the Coloring Compounds in Indigo, Phellodendron bark, and Madder Dye Using HPLC-DAD-MS

  • Ahn, Cheunsoon;Zeng, Xia;Obendorf, S. Kay
    • Journal of the Korean Society of Clothing and Textiles
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    • v.37 no.6
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    • pp.827-836
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    • 2013
  • Indigotin, indirubin, berberine, palmatine, alizarin, and purpurin are major pigments of indigo plant, Phellodendron bark, and madder. The six pigments were examined using the HPLC-DAD-MS instrument for the purpose of the simultaneous detection of the pigments in a single sample run. The HPLC-DAD-MS method examined the individual pigment solutions in DMSO, a solution containing 6 pigments, and the DMSO extract of the silk dyed with a dye solution of 5 pigments excluding indirubin. The retention times of the HPLC chromatograms, ${\lambda}_{max}$ of the uv-vis absorption bands in the DAD analyses, and the molecular ions detected for the compound peaks in the MSD analyses were consistent throughout the analyses of individual pigment solutions, mixed pigment solutions, and dye extracted from silk dyeing. The developed instrumental method of the simultaneous detection of six pigments can identify dye in an exhumed textile if the textile is dyed using any one (or multiple) pigments of indigo, Phellodendron bark, or madder plant.

Partial EBG Structure with DeCap for Ultra-wideband Suppression of Simultaneous Switching Noise in a High-Speed System

  • Kwon, Jong-Hwa;Kwak, Sang-Il;Sim, Dong-Uk;Yook, Jong-Gwan
    • ETRI Journal
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    • v.32 no.2
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    • pp.265-272
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    • 2010
  • To supply a power distribution network with stable power in a high-speed mixed mode system, simultaneous switching noise caused at the multilayer PCB and package structures needs to be sufficiently suppressed. The uni-planar compact electromagnetic bandgap (UC-EBG) structure is well known as a promising solution to suppress the power noise and isolate noise-sensitive analog/RF circuits from a noisy digital circuit. However, a typical UC-EBG structure has several severe problems, such as a limitation in the stop band's lower cutoff frequency and signal quality degradation. To make up for the defects of a conventional EBG structure, a partially located EBG structure with decoupling capacitors is proposed in this paper as a means of both suppressing the power noise propagation and minimizing the effects of the perforated reference plane on the signal quality. The proposed structure is validated and investigated through simulation and measurement in both frequency and time domains.

Vertical Augmentation of Maxillary Posterior Alveolar Ridge Using Allogenic Block Bone Graft and Simultaneous Maxillary Sinus Graft

  • Lee, Eun-Young;Kim, Eun-Suk;Kim, Kyoung-Won
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.36 no.5
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    • pp.224-229
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    • 2014
  • The maxillary posterior area is the most challenging site for the dental implant. Although the sinus graft is a predictable and successful technique for rehabilitation of atrophic and pneumatized posterior maxilla, when there is severe destruction of alveolar bone, a very long crown length remains challenging after successful dental implants installation with sinus graft. We performed vertical augmentation of the maxillary posterior alveolar ridge using the allogenic block bone graft with a simultaneous sinus graft using allogenic and heterogenic bone chips. After about six months, we installed the dental implant. After this procedure, we achieved a more favorable crown-implant fixture ratio and better results clinically and biomechanically. This is a preliminary report of vertical augmentation of maxillary posterior alveolar ridge using allogenic block bone graft and simultaneous maxillary sinus graft. Further research requires longer observation and more patients.

Simultaneous modulation of digital/SCM signal using a single LD for broadcasting in PON based optical access network (PON 기반 광가입자망에서 방송 신호 전송을 위한 단일 LD을 이용한 디지털/SCM 신호 동시 변조기술)

  • Kim Tae-Young;Kim Kyung-Hyun;Han Sang-Kook
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.5 s.347
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    • pp.1-6
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    • 2006
  • By comparing video-overlay method where digital and SCM signal are modulated in different optical source, we experimentally investigated the performance of simultaneous modulation of data and broadcasting signals using a single LD for broadcasting in PON based optical access network. The experimental results show that by increasing the minimum value of injected current for LD modulation above about 1.5 times of threshold current of LD, data and broadcasting signals can modulate without mutual interference. We also proposed and demonstrated the scheme of optical transmitter optimized for simultaneous modulation of data and broadcasting signals where anode and cathode of LD are separately used as signal interface for data and broadcasting signals, respectively.

Magnetic Resonance Imaging (MRI) of a Hypertrophy of Cartilage and Simultaneous Regeneration of a Damaged Meniscus after Autologous Bone Marrow Aspirates Concentrate (BMAC) Transplantation: a Case Report and Literature Review

  • Bae, Sung Hwan;Kim, Hyun-joo;Oh, Eunsun;Hwang, Jiyoung;Hong, Seong Sook;Hwang, Jung Hwa
    • Investigative Magnetic Resonance Imaging
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    • v.21 no.3
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    • pp.187-191
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    • 2017
  • Bone marrow aspirates concentrate (BMAC) transplantation is a well-known technique for cartilage regeneration with good clinical outcomes for symptoms in patients with osteoarthritis (OA). Magnetic resonance imaging (MRI) has an important role in evaluating the degree of cartilage repair in cartilage regeneration therapy instead of a second assessment via an arthroscopy. We experienced a case of hypertrophic regeneration of the cartilage and a presumed simultaneous regeneration of the posterior horn of the lateral meniscus after BMAC transplantation for a cartilage defect at the lateral tibial and femoral condyle. This report provides the details of a case of an unusual treatment response after a BMAC transplant. This report is the first of its kind to demonstrate a MR image that displays the simultaneous regeneration of the cartilage and meniscus with a differentiation ability of the mesenchymal stem cell to the desired cell lineage.