• The Journal of Korean Society for Radiation Therapy
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• 제25권2호
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• pp.123-129
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• 2013

Purpose: The way check the movement of the fiducial marker insertion in the treatment of patients with prostate cancer. However the existing methods of fiducial marker verification process difficult to identify the specific location of the marker behind the femur and pelvic bone. So to study the evaluation of maker match with using kilo voltage (KV) X-ray by On-board imager to both oblique verification method. Materials and Methods: Five patients were selected for rectal ballooning and inserted fiducial marker. Compare the position of the fiducial marker of reference plan 2D/2D Anterior/Posterior verification method and 2D/2D both oblique verification method. So to measurement the shift score of X, Y, Z (axis) and measure exposure dose given to patients and compare matching time. Results: 2 dimensional OBI KV X-ray imaging using two-dimensional matching image are orthogonal, so locating fiducial marker matching clear and useful DRR (digital reconstruction radiography) OBI souce angle ($45^{\circ}/315^{\circ}$) matching most useful. 2D/2D both oblique verification method was able to see clearly marker behind the pelvic bone. Also matching time can be reduced accordingly. According to the method of each matching results for each patient in each treatment fraction, X, Y, and Z axis the Mean $value{\pm}SD$ (standard deviation) is X axis (AP/LAT: $0.4{\pm}1.67$, OBLIQUE: $0.4{\pm}1.82$) mm, Y axis (AP/LAT: $0.7{\pm}1.73$, OBLIQUE: $0.2{\pm}1.77$) mm, Z axis (AP/LAT: $0.8{\pm}1.94$, OBLIQUE:$1.5{\pm}2.8$) mm. In addition, the KV X-ray source dose radiation exposure given to the patient taking average when AP/LAT matching is (0.1/2.1) cGY, when $315^{\circ}/45^{\circ}$ matching is (0.27/0.26) cGY. Conclusion: In conclusion for inserted fiducial marker of prostate cancer patients 2D/2D both oblique matching method is more accurate verification than 2D/2D AP/LAT matching method. Also the matching time less than the 2D/2D AP/LAT matching method. Taken as the amount of radiation exposure to patients less than was possible. Suggest would improve the treatment quality of care patients more useful to establish a protocol such as case.

• Investigative Magnetic Resonance Imaging
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• 제13권2호
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• pp.152-160
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• 2009

Purpose : To intra-individually compare diagnostic accuracy of high-resolution contrast-enhanced magnetic resonance angiography (CE-MRA) with computed tomography angiography (CTA) and digital subtraction angiography (DSA) for the assessment of supraaortic steno-occlusive disease. Materials and Methods : Twenty-eight patients (20 men, 8 women, 53-79 years of age) underwent supraaortic CE-MRA, CTA and DSA. CE-MRA was performed on two 1.5T MR scanners (voxel dimension: $0.66{\times}0.66{\times}1.1$ or $1.2\;mm^3$), and CTA on 64-slice CT scanners (voxel dimension: $0.42{\times}0.42{\times}0.63\;mm^3$). All the three examinations were completed within 40 days (median 19 days; range 1-40 days). Retrospective evaluation and measurement of diameter of 6 extracranial and 9 intracranial arterial segments was done by 2 experienced radiologists. Results: A total of 420 arterial segments were examined by CE-MRA, CTA and DSA. On DSA, 34 stenoocclusive lesions were noted at extracranial (n= 19) and intracranial (n = 15) vessels. For extracranial stenosis greater than 70%, sensitivity, specificity, positive predictive value (PPV) and negative predictive values (NPV) were 94.7%, 98.7%, 90.0% and 99.3% on CE-MRA, and 94.7%, 99.3%, 94.7% and 99.3% on CTA. For intracranial stenosis greater than 50%, sensitivity; specificity, PPV and NPV were 93.3%, 98.3%, 77.8%and 99.6% on CE-MRA, and 86.7%, 97.9%, 72.2% and 99.1 % on CTA, with DSA as the standard of reference. Conclusion : Supraaortic CE-MRA is as reliable as CTA in depicting the arterial stenosis, and is effective in screening of significant stenosis of both extracranial and intracranial arterial stenosis.

• Journal of Internet Computing and Services
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• 제17권1호
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• pp.101-107
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• 2016

Due to the recent advancement in digital imaging technology, development of intervention equipment has become generalize. Video arbitration procedure is a process to insert a tiny catheter and a guide wire in the body, so in order to enhance the effectiveness and safety of this treatment, the high-quality of x-ray of image should be used. However, the increasing of radiation has become the problem. Therefore, the studies to improve the performance of x-ray detectors are being actively processed. Moreover, this intervention is based on the reference of the angiographic imaging and 3D medical image processing. In this paper, we propose a guidance system to support this intervention. Through this intervention, it can solve the problem of the existing 2D medical images based vessel that has a formation of cerebrovascular disease, and guide the real-time tracking and optimal route to the target lesion by intervention catheter and guide wire tool. As a result, the system was completely composed for medical image acquisition unit and image processing unit as well as a display device. The experimental environment, guide services which are provided by the proposed system Brain Phantom (complete intracranial model with aneurysms, ref H+N-S-A-010) was taken with x-ray and testing. To generate a reference image based on the Laplacian algorithm for the image processing which derived from the cerebral blood vessel model was applied to DICOM by Volume ray casting technique. $A^*$ algorithm was used to provide the catheter with a guide wire tracking path. Finally, the result does show the location of the catheter and guide wire providing in the proposed system especially, it is expected to provide a useful guide for future intervention service.

• The Korean Journal of Nuclear Medicine Technology
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• 제14권2호
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• pp.166-171
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• 2010

Purpose: The SPECT/CT is able to acquire diagnostic information resolved the difficult problems that discriminate regions of focals by intergrating functional images and anatomical images. We introduce the usefulness of "Volumetrix Suite" which can describe 3D images by the convergence of the SPECT/CT images and reference CT images. Materials and Methods: We applied Volumetrix Suite program (Volumetrix IR, Volumetrix 3D) to patients, Bone, Venography, Parathyroid, WBC, taken diagnostic CT examination which have same regions of focal in Seoul Metropolitan Government Seoul National University Boramae Medical Center. After acquiring SPECT/CT images and reference CT images, we fused a couple of scans applying for this programs. The CT scan of Infinia Hawkeye 4 shows limitation of anatomical information. For this reason, we tried to transfer CT images that have lots of diagnostic informations as the form of Dicom file in PACS, and changed from 2D images to 3D images after image registering in Xeleris Workstaion of Hawkeye 4. Results & Conclusion: By using Volumetrix Suite program, we're able to acquire more accurate anatomical informations with 3D rendering which can distinguish both location and range of focals in Infinia Hawkeye 4. Thus, the result of utilizing this program indicate that nuclear medicine anatomical images can be improved by providing more diagnostic imformations produced by its program.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제22권6호
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• pp.1210-1230
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• 1997

In this paper, we suggest an architecture of DS/CDMA tranceiver composed of one pilot channel used as reference and multiple traffic channels. The pilot channel-an unmodulated PN code-is used as the reference signal for synchronization of PN code and data demondulation. The coherent demodulation architecture is also exploited for the reverse link as well as for the forward link. Here are the characteristics of the suggested DS/CDMA system. First, we suggest an interlaced quadrature spreading(IQS) method. In this method, the PN coe for I-phase 1st channel is used for Q-phase 2nd channels and the PN code for Q-phase 1st channel is used for I-phase 2nd channel, and so on-which is quite different from the eisting spreading schemes of DS/CDMA systems, such as IS-95 digital CDMA cellular or W-CDMA for PCS. By doing IQS spreading, we can drastically reduce the zero crossing rate of the RF signals. Second, we introduce an adaptive threshold setting for the synchronization of PN code, an initial acquistion method that uses a single PN code generator and reduces the acquistion time by a half compared the existing ones, and exploit the state machines to reduce the reacquistion time Third, various kinds of functions, such as automatic frequency control(AFC), automatic level control(ALC), bit-error-rate(BER) estimator, and spectral shaping for reducing the adjacent channel interference, are introduced to improve the system performance. Fourth, we designed and implemented the DS/CDMA MODEM to be used for variable transmission rate applications-from 16Kbps to 1.024Mbps. We developed and confirmed the DS/CDMA MODEM architecture through mathematical analysis and various kind of simulations. The ASIC design was done using VHDL coding and synthesis. To cope with several different kinds of applications, we developed transmitter and receiver ASICs separately. While a single transmitter or receiver ASC contains three channels (one for the pilot and the others for the traffic channels), by combining several transmitter ASICs, we can expand the number of channels up to 64. The ASICs are now under use for implementing a line-of-sight (LOS) radio equipment.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제22권3호
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• pp.679-687
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• 2021

The purpose of the present study was to document the standardization and management process of interface terminology regarding the chief complaints, diagnoses, and procedures, including surgery in a four-hospital consortium. The process was proposed, discussed, modified, and finalized in 2016 by the Terminology Standardization Committee (TSC), consisting of personnel from four hospitals. A request regarding interface terminology was classified into one of four categories: 1) registration of a new term, 2) revision, 3) deleting an old term and registering a new term, and 4) deletion. A request was processed in the following order: 1) collecting testimonies from related departments and 2) voting by the TSC. At least five out of the seven possible members of the voting pool need to approve of it. Mapping to the reference terminology was performed by three independent medical information managers. All processes were performed online, and the voting and mapping results were collected automatically. This process made the decision-making process clear and fast. In addition, this made users receptive to the decision of the TSC. In the 16 months after the process was adopted, there were 126 new terms registered, 131 revisions, 40 deletions of an old term and the registration of a new term, and 1235 deletions.

• Information Systems Review
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• 제10권3호
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• pp.1-20
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• 2008

Under the rubric of the new economy, a wide variety of economic and social phenomena have been identified and discussed since the 1990's. Most of the observations in the literature on the new economy are fragmented, casual, and anecdotal, not compiling to a whole picture of what the new economy is really about. Therefore, this study attempts to provide e-commerce companies with a better, more systematic understanding of the new economy and new economy phenomena as well as the implications of them in order to help them develop more effective business strategies. To provide a better understanding of the new economy phenomena, this article adopts system perspective as an overarching frame of reference for analysis. The systemic characteristics and behavior of the new economy is sought in five generic aspects of a system; 1) what are the entities that comprise the system, and how are they related to one another?; 2) how does the system function?; 3) what are the goods and services (output) that are generated and flow in the system?; 4) what is the value of those goods and services?; and 5) what are the collective, systemic quality and attributes of the system? Based upon the review and categorization, some essential characterizations are made for the five system aspects of the new economy. Such characterizations are interpreted as collectively enunciating the systemic characteristics and behavior of the new economy. The implications of the systemic under-standing of the new economy for business and firm strategy are discussed and some future research is suggested.

• Journal of the Korean Association of Geographic Information Studies
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• 제2권2호
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• pp.79-86
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• 1999

This study was carried out to estimate the area of damaged forest and the volume of stand tree in burned area, Mt. Weol-A in eastern Chinju, Korea using digital maps derived from supervised classification of Landsat thematic mapper(TM) imagery as reference data. Criterion laser estimator and WinDENDRO$^{tm}$(v. 6.3b) system as a computer-aided tree ring measuring system were used to measure a volume and age of sampled tree. The sample site had been chosen in unburned areas having the same terrain condition and forest type of burned areas. The tree age, diameter at breast height, tree height and volume of the sample tree selected from sample site in unburned area were 27years, 20.9cm, 9.7m and $0.1396m^3$ respectively. Total stand volume of sample site was estimated $2.9316m^3$/0.04ha, Damaged stand volume evaluated to about $16,007m^3$ in the burned area of 218.4ha.

• Journal of the Institute of Electronics Engineers of Korea SD
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• 제43권12호
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• pp.55-64
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• 2006

This work proposes a calibration-free 14b 70MS/s 0.13um CMOS ADC for high-performance integrated systems such as WLAN and high-definition video systems simultaneously requiring high resolution, low power, and small size at high speed. The proposed ADC employs signal insensitive 3-D fully symmetric layout techniques in two MDACs for high matching accuracy without any calibration. A three-stage pipeline architecture minimizes power consumption and chip area at the target resolution and sampling rate. The input SHA with a controlled trans-conductance ratio of two amplifier stages simultaneously achieves high gain and high phase margin with gate-bootstrapped sampling switches for 14b input accuracy at the Nyquist frequency. A back-end sub-ranging flash ADC with open-loop offset cancellation and interpolation achieves 6b accuracy at 70MS/s. Low-noise current and voltage references are employed on chip with optional off-chip reference voltages. The prototype ADC implemented in a 0.13um CMOS is based on a 0.35um minimum channel length for 2.5V applications. The measured DNL and INL are within 0.65LSB and l.80LSB, respectively. The prototype ADC shows maximum SNDR and SFDR of 66dB and 81dB and a power consumption of 235mW at 70MS/s. The active die area is $3.3mm^2$.

• Journal of the Institute of Electronics Engineers of Korea SP
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• 제47권6호
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• pp.75-81
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• 2010

The segmentation of cartilage is crucial for the diagnose and treatment of osteoarthritis (OA), and has mostly been done manually by an expert, requiring a considerable amount of time and effort due to the thin shape and vague boundaries of the cartilage in MR (magnetic resonance) images. In this paper, we propose a fully automatic method to segment cartilage in a knee joint on MR images. The proposed method is based on a small number of manually segmented images as the training set and comprised of an initial per patch segmentation process and a global refinement process on the cumulative per patch results. Each patch for per patch segmentation is positioned by classifying the bone-cartilage interface on the pre-segmented bone surface. Next, the shape and intensity priors are constructed for each patch based on information extracted from reference patches in the training set. The ratio of influence between the shape and intensity priors is adaptively determined per patch. Each patch is segmented by graph cuts, where energy is defined based on constructed priors. Finally, global refinement is conducted on the global cartilage using the results of per patch segmentation as the shape prior. Experimental evaluation shows that the proposed framework provide accurate and clinically useful segmentation results.