• Analytical Science and Technology
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• 제25권5호
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• pp.292-299
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• 2012

GC/MS has been utilized for many applications due to great resolution and reproducibility, which made it possible to build up the database of mass spectrum, while HS-SPME has the advantage of solventfree extraction of volatile compounds. The combination of these two methods, HS-SPME GC/MS, enabled many scientific applications with various possibilities. In this study, the analysis of trail pheromone excreted from live Camponotus japonicus with the feature of solvent-free extraction was carried out and the optimization for this analysis was performed. The major compounds detected were n-decane, n-undecane, and n-tridecane. Optimization for the best detection of these hydrocarbons was processed in the point of SPME parameter (selection of fiber, extraction temperature, extraction time, etc.). The advantage of the analysis of live sample is to analyze phenomenon right after it is excreted by ants. But the experimental process has restriction of extraction temperature and time because of the analysis of live ants. Establishing the process of HS-SPME GC/MS applied to live samples shown in this study can be a breakthrough for the ecofriendly and ethical research of live things.

• Journal of Biomedical Engineering Research
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• 제19권3호
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• pp.251-260
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• 1998

The Holter monitoring system is a widely used noninvasive diagnostic tool for ambulatory patient who may be at risk from latent life-threatening cardiac abnormalities. In this paper, we design a high performance intelligent holter monitoring system which is characterized by the small-sized and the low-power consumption. The system hardware consists of one-chip microcontroller(68HC11E9), ECG preprocessing circuit, and flash memory card. ECG preprocessing circuit is made of ECG preamplifier with gain of 250, 500 and 1000, the bandpass filter with bandwidth of 0.05-100Hz, the auto-balancing circuit and the saturation-calibrating circuit to eliminate baseline wandering, ECG signal sampled at 240 samples/sec is converted to the digital signal. We use a linear recursive filter and preprocessing algorithm to detect the ECG parameters which are QRS complex, and Q-R-T points, ST-level, HR, QT interval. The long-term acquired ECG signals and diagnostic parameters are compressed by the MFan(Modified Fan) and the delta modulation method. To easily interface with the PC based analyzer program which is operated in DOS and Windows, the compressed data, that are compatible to FFS(flash file system) format, are stored at the flash memory card with SBF(symmetric block format).

• The Journal of Korean Institute of Communications and Information Sciences
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• 제40권4호
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• pp.700-708
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• 2015

A software birthmark is the set of characteristics of a program which can be used to identify the program. Many researchers have studied on detecting theft of java programs using some birthmarks. In case of Android apps, code obfuscation techniques are used to protect the apps against reverse-engineering and tampering. However, attackers can also use the obfuscation techniques in order to conceal a stolen program. A birthmark (feature) of an app can be alterable by code obfuscations. Therefore, it is necessary to detect Android app theft based on the birthmark which is resilient to code obfuscation. In this paper, we propose an effective Android app birthmark and app theft detection through the proposed birthmark. By analyzing some obfuscation tools, we have first selected parameter and the return types of methods as an adequate birthmark. Then, we have measured similarity of target apps using the birthmarks extracted from the apps, where some target apps are not obfuscated and the others obfuscated. The measurement results show that our proposed birthmark is effective for detecting Android app theft even though the apps are obfuscated.

• Journal of Chest Surgery
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• 제30권11호
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• pp.1055-1061
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• 1997

In the field of the experimental lung transplantation, we analyzed the CT findings of acute rejection, infection in the left single allotransplanted lung of adult mongrel dogs, and the CT findings were compared with the histological findings obtained by the lung biopsy Twenty two adult mongrel dogs were divided into two groups(Donor and recipient group). Donor lungs were flushed with LPDG(low pota,ilium dextral glucose) solution(n=4) or modified Euro-collins solution(n=7) and preserved over 20 hours with $10^{\circ}C(1$ case preservation for 4hours). After left single lung transplantation, the chest X-ray and sequential computed tomogram were performed with concomitant hemodynamic study and arterial blood gas analysis on immediate postoperative period, postoperative 3rd day and postoperative 7th day. Two of eleven transplanted lungs had acute rejection which was represented as moderate infiltration at immediate or 1st postoperative d y but became extensive infiltration at postoperative 3rd day on CT. There were showed one case of bronchopleural fistula, six cases of pneumonia and two cases of pulmonary infarction. In one rejection cases, the opacity of transplanted lung was improved by injection of methylprednisolone 500mg daily during 3 days. We concluded that CT was a useful noninvasive evaluation parameter after lung transplantation and the serial CT scan enabled early detection of acute rejection.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• 제24권9호
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• pp.944-950
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• 2013

This paper is a study of a rain sensor using an open-ended coaxial cavity resonator which senses the amount of rain drops linearly. It shows that it will be used as a sensor to sense the amount of rain dropped on the windshield of an automobile based on the principle of varied resonant frequency and the loss according to the amount and characteristics of an dielectric lied on the open side of a resonator. The input and output ports are built in the both sides of the resonator and the input and output coupling probes are formed like 'ㄱ' shape. The response of rain drops were simulated by the radius of inner conductor of 2 mm, 5 mm, and 10 mm respectively and it showed that the raindrop was sensed most linearly and sensitively when the radius of inner conductor is 5 mm, We have measured that the resonant frequency have varied from 3.55 GHz to 3 GHz and the Q value have varied from 42.38 to 24.3 according to the variation of rain drop amount on the fabricated resonator. Therefore, it shows that the designed resonator can be applied as a rain sensor that measures the amount of rain drops linearly by using the resonant frequency as a measurement parameter.

• Journal of the Korean Institute of Intelligent Systems
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• 제26권4호
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• pp.253-258
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• 2016

This paper proposes a method that utilizes optimization approach for localization of an indoor mobile robot. Bayesian filters which have been widely used for localization of a mobile robot use many control parameters to take the uncertainties in measurement and environment into account. The estimation performance depends on the selection of these parameter values. Also, the performance of the Bayesian filters deteriorate as the non-linearity of the motion and measurement increases. On the other hand, the optimization approach uses fewer control parameters and is less influenced by the non-linearity than the Bayesian methods. This paper compares the localization performance of the proposed method with the performance of the extended Kalman filter to verify the feasibility of the proposed method. Measurements of ranges from beacons of ultrasonic satellite to the robot are used for localization. Mahalanobis distance is used for detection and rejection of outlier in the measurements. The optimization method sets performance index as a function of the measured range values, and finds the optimized estimation of the location through iteration. The method can improve the localization performance and reduce the computation time in corporation with Bayesian filter which provides proper initial location for the iteration.

• KSCE Journal of Civil and Environmental Engineering Research
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• 제37권1호
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• pp.43-59
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• 2017

This study presents the prediction methodology of debris flow occurrence areas using the SINMAP model. Former studies used a single calibration region applying some of the soil test results to predict debris flow occurrence in SINMAP model, which couldn't subdivide the soil properties for the target areas. On the other hands, a multi-calibration region using a detailed soil map and soil strength parameters (c, ${\phi}$) for each soil series to make up for limitation of former studies is proposed. In this process, soils with soil erodibility factor (K) are classified into three types: 1) gravel and gravelly soil. 2) sand and sandy soil, and 3) silt and clay. In addition, T/R estimation method using mean elevation of target area instead of T/R method using actual occurrence time is suggested in this study. The suggested method is applied to Seobyeok-1 ri area, Bonghwa-gun where debris flow occurred. As a result of comparison between two T/R estimation method, both T/R estimations are almost equal. Therefore, the suggested methodologies in this study will contribute to set up the national-wide mitigation plan against debris flow occurrence.

• Tuberculosis and Respiratory Diseases
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• 제54권5호
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• pp.532-541
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• 2003

Background : Phospholipase $A_2$ ($PLA_2$) has been known to be involved in the pathogenesis of acute lung injury (ALI) including ARDS. Since doxycycline has the property of inhibiting secretory group II $PLA_2$, the therapeutic effect of doxycycline hyclate was investigated for gut ischemia/reperfusion (I/R)-induced ALI in Sprague-Dawley rats. Methods : ALI was induced in Sprague-Dawley rats by clamping of the superior mesenteric artery for 60 min, followed by 120 min of reperfusion. To confirm the pathogenetic mechanisms of this ALI associated with neutrophilic oxidative stress, we measured bronchoalveolar lavage (BAL) protein content and lung MPO, and performed cyto-chemical electron microscopy for detection of free radicals, assay of $PLA_2$ activity and cytochrome-c reduction assay. Results : In gut I/R-induced ALI rats, protein leakage, pulmonary neutrophil accumulation, free radical production and lung $PLA_2$ activity were all increased. These effects were reversed by doxycycline hyclate. Conclusion : Doxycycline appears to be effective in ameliorating the gut I/R-induced ALI by inhibiting $PLA_2$, thereby decreasing the production of free radicals from neutrophils.

• Journal of Biomedical Engineering Research
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• 제20권1호
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• pp.81-90
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• 1999

This paper describes an EEG(electroencephalogram) software for two-channel cerebral function monitoring system to detect the cerebral ischemia. In the software, two-channel bipolar analog EEG signals are digitized and from the signals various EEG parameters are extracted and displayed on a monitor in real-time. Digitized EEG signal is transformed by FFT(Fast Fourier transform) and represented as CSA(compressed spectral array) and DSA(density spectral array). Additional 5 parameters, such as alpha ratio, percent delta, spectral edge frequency, total power, and difference in total power, are estimated using the FFT spectra. All of these are effectively merged in a monitor and displayed in real-time. Through animal experiments and clinical trials on men, the software is modified and enhanced. Since the software provides raw EEG, CSA, DSA, simultaneously with additional 5 parameters in a monitor, it is possible to observe patients multilaterally. For easy comparison of patient's status, reference patterns of CSA, DSA can be captured and displayed on top of the monitor. And user can mark events of surgical operation and patient's conditions on the software, this allow him jump to the points of events directly, when reviewing the recorded EEG file afterwards. Other functions, such as forward/backward jump, gain control, file management are equipped and these are operated by simple mouse click. Clinical tests in a university hospital show that the software responds accurately according to the conditions of patients and medical doctors can use the software easily.

• Journal of Korean Neurosurgical Society
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• 제56권3호
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• pp.218-223
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• 2014

Objective : C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are often utilized to evaluate for postoperative infection. Abnormal values may be detected after surgery even in case of non-infection because of muscle injury, transfusion, which disturbed prompt perioperative management. The purpose of this study was to evaluate and compare the perioperative CRP, ESR, and white blood cell (WBC) counts after spine surgery, which was proved to be non-infection. Methods : Twenty patients of lumbar open discectomy (LOD) and 20 patients of posterior lumbar interbody fusion (PLIF) were enrolled in this study. Preoperative and postoperative prophylactic antibiotics were administered routinely for 7 days. Blood samples were obtained one day before surgery and postoperative day (POD) 1, POD3, and POD7. Using repeated measures ANOVA, changes in effect measures over time and between groups over time were assessed. All data analysis was conducted using SAS v.9.1. Results : Changes in CRP, within treatment groups over time and between treatment groups over time were both statistically significant F(3,120)=5.05, p=0.003 and F(1,39)=7.46, p=0.01, respectively. Most dramatic changes were decreases in the LOD group on POD3 and POD7. Changes in ESR, within treatment groups over time and between treatment groups over time were also found to be statistically significant, F(3,120)=6.67, p=0.0003 and F(1,39)=3.99, p=0.01, respectively. Changes in WBC values also were be statistically significant within groups over time, F(3,120)=40.52, p<0.001, however, no significant difference was found in between groups WBC levels over time, F(1,39)=0.02, p=0.89. Conclusion : We found that, dramatic decrease of CRP was detected on POD3 and POD7 in LOD group of non-infection and dramatic increase of ESR on POD3 and POD7 in PLIF group of non-infection. We also assumed that CRP would be more effective and sensitive parameter especially in LOD than PLIF for early detection of infectious complications. Awareness of the typical pattern of CRP, ESR, and WBC may help to evaluate the early postoperative course.