• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.613-618
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• 2020

The average dose of Fast Low Dose C-arm CT used during hepatic arterial chemoembolization was compared with the average dose of DSA, and the exposure dose was analyzed by analyzing the average dose for each test technique in the total accumulated dose. 50 patients were randomly selected at our clinic and compared with Fast Low Dose C-arm CT, DAP and Air Kerma of DSA, and the accumulation of four test techniques (DSA, Fast Low Dose C-arm CT, Roadmap, Fluoroscopy) The proportion of dose (DAP, Air Kerma) was analyzed. For statistical comparative analysis, the corresponding sample T test and ANOVA test (post hoc test: Tukey) were performed using the statistical program SPSS 20.0. Fast Low Dose C-arm CT showed statistically significantly lower average dose (DAP, Air Kerma) than DSA. Reducing the number of tests for DSA can reduce the patient's exposure to medical radiation.

• The Journal of the Korea Contents Association
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• v.12 no.1
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• pp.80-90
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• 2012

Medical data sampled through medical sensor nodes can provide services properly only when the data are not lost even during the fault of a home health gateway. The loss of medical data can be minimized if a sensor node, in which it is expected that there are the most saving spaces, is selected after medical sensor nodes tentatively conduct local save or communicate with each other during a fault when data cannot received. Furthermore, efficient saving techniques are necessary since the cycle for sampling information is different according to the type of medical data and a space for distributed saving is different for each apparatus. So, this research suggests an efficient distributed archiving protocol (DAP) for medical data sensor nodes, each of which has a diverse sampling cycle. In order to confirm the usefulness of DAP, DAP between sensor node and gateway was designed and materialized. An experiment was conducted using the materialized program and earned a high level of recovery rate (99.3%) and of accuracy rate, which confirms that sensor nodes can play their role during a temporary fault.

• Imaging Science in Dentistry
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• v.42 no.4
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• pp.237-242
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• 2012

Purpose: The objectives of this study were to survey the radiographic exposure parameters, to measure the patient doses for intraoral dental radiography nationwide, and thus to establish the diagnostic reference levels (DRLs) in intraoral dental X-ray examination in Korea. Materials and Methods: One hundred two intraoral dental radiographic machines from all regions of South Korea were selected for this study. Radiographic exposure parameters, size of hospital, type of image receptor system, installation duration of machine, and type of dental X-ray machine were documented. Patient entrance doses (PED) and dose-area products (DAP) were measured three times at the end of the exit cone of the X-ray unit with a DAP meter (DIAMENTOR M4-KDK, PTW, Freiburg, Germany) for adult mandibular molar intraoral dental radiography, and corrections were made for room temperature and pressure. Measured PED and DAP were averaged and compared according to the size of hospital, type of image receptor system, installation duration, and type of dental X-ray machine. Results: The mean exposure parameters were 62.6 kVp, 7.9 mA, and 0.5 second for adult mandibular molar intraoral dental radiography. The mean patient dose was 2.11 mGy (PED) and 59.4 $mGycm^2$ (DAP) and the third quartile one 3.07 mGy (PED) and 87.4 $mGycm^2$ (DAP). Doses at university dental hospitals were lower than those at dental clinics (p<0.05). Doses of digital radiography (DR) type were lower than those of film-based type (p<0.05). Conclusion: We recommend 3.1 mGy (PED), 87.4 $mGycm^2$ (DAP) as the DRLs in adult mandibular molar intraoral dental radiography in Korea.

• Journal of the Korean Chemical Society
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• v.36 no.6
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• pp.840-848
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• 1992

An ionizable macrocyclic ligand, diaza-18-crown-6-diisopropionic acid(K22DAP) has been synthesized. Protonation constants of this compound and stability constants with some lanthanides were determined by potentiometric titration method. The protonation constants are log$K_1$ = 9.05, log$K_2$ = 8.37, log$K_3$ = 1.88 and log$K_4$ = 0.99. The logarithmic values of stability constants with La(III), Nd(III), Gd(III) and Lu(III) are 11.14, 11.43, 11.74 and 10.88 respectively. Extraction behavior of Ln(III) ion was investigated using TTA(thenoyltrifluoroacetone) as extractant in the presence of K22DAP as macrocyclic ionophore. It was observed that Ln(K22DAP)TTA is the dominating species in aqueous complexes of La(III) and Nd(III).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.10
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• pp.977-985
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• 2012

Recently, many countries have been developing new protocols to improve the performance of tactical ad hoc networks for implementing NCW (Network Centric Warfare). Combat net radio (CNR) networks are the most important communication infra for the ground forces such as infantry of Army. U.S. Army had developed MIL-STD-188-220D that is the Interoperability Standard for DMTDs (Digital Messages Transfer Device Subsystems) for voice and data communication in CNR. MIL-STD-188-220D is a candidate for MAC protocol of TMMR which is next radio and has a few constraints to used in TMMR. NAD (Network Access Delay) defined in MIL-STD-188-220D needs time synchronization to avoid collision. However, it is difficult for time synchronization to fit in multi-hop environment. We suggest the enhanced DAP (Deterministic Adaptable Priority)-NAD to prevent conflicts and decrease delays in multi-hop CNR. Simulation results show that the proposed scheme improves the performance in multi-hop CNR networks.

• The Journal of the Korea Contents Association
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• v.12 no.3
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• pp.244-250
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• 2012

The results of analyzing the difference between performances of individual dosimeters on this research subjecting the PLD and TLD, which are the official personal dosimeters, through dosimetry are as follows. After scanning the integral dose using an automatic scanner, the values of two devices that went through dose adjustment process had a statistical difference in TLD and PLD measurements under each filming conditions which were 70kVp, 200mA, 0.012sec and 42kVp, 100mA, and 0.012sec (p<0.001 and p<0.001 respectively). As for the difference of measurement value between DAP and the two particles under 70kVp, 200mA, 0.012sec filming condition, TLD had a value lower than DAP average value by $44.2mGy{\cdot}cm^2$ and PLD had a value of $246.8mGy{\cdot}cm^2$ which was lower than DAP average value by $15.5mGy{\cdot}cm^2$, while under 42kVp, 100mA, 0.012sec filming condition, TLD had a value lower than DAP average value by $17.9mGy{\cdot}cm^2$ and PLD had a value of $82.6mGy{\cdot}cm^2$ which was lower than DAP average value by 7.6$mGy{\cdot}cm^2$. Also, compared to PLD, each of 10 devices measured dose value in TLD had a larger deviation between the particles, and for a reproducibility test which repeatedly measured one particle, PLD had ${\pm}1%$ which was lower than TLD's ${\pm}2%$. As such, PLD had a superior performance result in dose measurement capacities aspect compared to TLD, and therefore we could verify that PLD is more appropriate and advantageous in managing radiation-related task performing worker's personal radiation exposure management in the diagnostic radiation field.

• Tuberculosis and Respiratory Diseases
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• v.55 no.4
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• pp.378-387
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• 2003

Background : Promoter methylation of tumor suppressor genes is one of the key epigenetic changes in many human cancers. The aim of this study was to evaluate the promoter methylation status of the Death-associated protein(DAP) kinase gene, which played an important role in lung cancer, in the serum DNA of primary lung cancer patients. Methods : This study investigated the aberrant methylation of DAP kinase in the serum of 65 primary lung cancer patients by methylation-specific PCR (MSP). Results : Methylation in the serum was detected in 29 of 65(44.6%) for DAP kinase. There was no statistical association between methylation of DAP kinase and age, smoking history, histologic type, or stage. Methylation of DAP kinase was found more frequently in men (p=0.044). Conclusions : This study suggests that the aberrant methylation of the DAP kinase promoter is readily detectable in the serum DNA of lung cancer patients using MSP analysis.

• Tuberculosis and Respiratory Diseases
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• v.51 no.2
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• pp.108-121
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• 2001

Background : The $p16^{INK4a}$ (p16) twnor suppressor gene is frequently inactivated in hwnan non-small cell lung cancers (NSCLCs), predominantly through homozygous deletion or in association with aberrant promotor hypermethylation. Death-associated protein kinase (DAPK) gene influences interferon $\gamma$-induced apoptotic cell death and has important role in metastasis of lung cancer in animal model. Hypermethylation of promoter region of DAP kinase gene may suppress the expression of this gene. Methods : This study was performed to investigate the aberrant methylation of p16 or DAP kinase in 35 resected primary NSCLCs by methylation-specific PCR (MSP), and demonstrated frequency, diagnostic value and clinical implication of aberrant methylation of two genes. Results : Thirty-two cases were male patients, and 3 cases were female patients with an average age was 57. $8{\pm}10.5$ years. The histologic types of lung cancer were 22 of squamous cell carcinoma, 12 of adenocarcinoma, 1 of large cell carcinoma. Pathologic stages were 11 cases of stage I (1 IA, 10 IB), 13 cases of stage II (1 IIA, 12 IIB), and 11 cases of stage III (9 IIIA, 2 IIIB). Regarding for the cancer tissue, p16 aberrant methylation was noted in 13 case of 33 cases (39.4%), DAP kinase in 21 cases of 35 cases (60%). Age over 55 year was associated with p16 aberrant methylation significantly (p<0.05). Methylation status of two genes was not different by smoking history, histologic type, size of tumor, lymph node metastasis and disease progression of lung cancer. There was no correlation between p16 and DAP kinase hypermethylation. Conclusion: This investigation demonstrates that aberrant methylation of p16 tumor suppressor gene or DAP kinase showed relatively high frequency (74.3%) in NSCLCs, and that these genes could be a biologic marker for early detection of lung cancer.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.12
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• pp.147-151
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• 2016

Automatic exposure control (AEC) is frequently used in many hospitals for Standing Whole Spine examination which is able to control radiation dose with respect to the body type such as body mass index (BMI) and we can measure dose area product (DAP) based on respective patient information. However, few studies have been conducted organ absorbed dose evaluation based on location of patient organ. The purpose of this study was to evaluate the relationships between BMI and organ absorbed dose along with location of patient organ. For that purpose, we calculated absorbed dose with selected 5 patient organ (thyroid, breast, heart, kidney, and pancreas) using a PCXMC simulation tool with measured DAP. According to the results, measured DAP increases with BMI and organ absorbed dose decreases with BMI in anterior organs such as thyroid, breast, and heart. On the other hand, there is no correlation between organ absorbed dose and BMI in posterior organs such as kidney and pancreas. In conclusion, our results demonstrated that the radiation effects are different with respect to BMI and location of patient organ in Standing Whole Spine examination.

• Journal of radiological science and technology
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• v.39 no.3
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• pp.435-441
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• 2016

The importance of radiation dose display of medical X-ray equipment was emphasized, while third edition of IEC(International Electrotechnical Commission) 60601 started to apply. The existing medical X-ray equipment selected a method for attaching the DAP(Dose Area Product) meter when the dose display. However, because the DAP meter was dependent on all of the income, And it did not yet produced in Korea. So, we received the support of Seoul R&BD Program(Grants No. C1152055) to produce DAP meter prototype of the Domestically technology. In this study, the performance of this prototype was evaluated by comparing the German company's product Evaluation item was an electronic capture performance, radiation dose dependence, radiation quality dependence, energy transmittance, repeatability, light transmittance of 6 entries. And IEC 60580 was based on this evaluation. Evaluation results were electronic capture performance intrinsic error 9.5%, radiation dose dependence limits of variation 1%, repeatability coefficient of variation 2%, energy transmittance 91% each assessment was passed. However radiation quality dependence limits of variation 29%, light transmittance 55% was less than acceptance criteria.