Optical Image Encryption and Decryption Considering Wireless Communication Channels

( Myungjin Cho ),( In Ho Lee ) 한국정보처리학회 2014 Journal of information processing systems Vol.10 No.2

In this paper, we discuss optical encryption and decryption considering wireless communication channels. In wireless communication systems, the wireless channel causes noise and fading effects of the transmitted information. Optical encryption technique such as double-random-phase encryption (DRPE) is used for encrypting transmitted data. When the encrypted data is transmitted, the information may be lost or distorted because there are a lot of factors such as channel noise, propagation fading, etc. Thus, using digital modulation and maximum likelihood (ML) detection, the noise and fading effects are mitigated, and the encrypted data is estimated well at the receiver. To the best of our knowledge, this is the first report that considers the wireless channel characteristics of the optical encryption technique.

Bench-scale ex situ diesel removal process using a biobarrier and surfactant flushing

Myungjin Lee,이영철,우성근,Eun-Sil Choi,안영희,박준홍,양지원 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.3

Ex situ diesel removal was demonstrated using a biobarrier with immobilized cells and surfactant flushing in a bench-scale system. Four strains (two Acinetobacter sp., one Gordonia sp., and one Rhodococcus sp.) isolated from a diesel-contaminated site were immobilized onto a matrix to act as a biofiller. Peat moss, bentonite, and alginate were used as a hybrid support, and a procedure for the use of a bench-scale biobarrier was also employed. According to a microbial counting assay used for the biobarrier, the total amount of bacterial cells increased from approximately 2 109 to 8 109 (colony forming unit (CFU)/g) and the amount of inoculated diesel-degrading bacteria slightly increased from 2 106 to 5 106 (CFU/g) in the same period (over 30 days). This increase resulted in the reduction of diesel from 6000 45 mg/kg to below 5 mg/kg. While 99.9%, i.e. up to below 5 mg/L of the diesel in soil was treated during 30 days of operation, diesel biodegradation accounted for 24.3% of the reduction of diesel.

Design and Fabrication of Magnetophoretic Multilayer Microfluidic Chip with Polyurethane Acrylate Mesh

Myungjin Chung(정명진),Yong-Kweon Kim(김용권) 대한전기학회 2019 대한전기학회 학술대회 논문집 Vol.2019 No.7

Xanthine-derived Metabolites Enhance Chlorophyll Degradation in Cotyledons and Seedling Growth during Nitrogen Deficient Condition in Brassica rapa

Myungjin Lee,So Young Yi,Jana Jeevan Rameneni,Lu Lu,Chetan Kaur,Yong Pyo Lim 한국원예학회 2021 한국원예학회 학술발표요지 Vol.2021 No.10

Nitrogen (N) deficiency is a main environmental factor that induces early senescence. Cotyledons provide an important N source during germination and early seedling development. In this study, we observed that N deficient condition enhanced gene expression involved in purine catabolism in cotyledons of Chinese cabbage (Brassica rapa ssp. Pekinensis). Seedlings grown with added allopurinol, an inhibitor of xanthine dehydrogenase, in the growth medium showed reduced chlorophyll degradation in cotyledons and lower fresh weight, compared with seedlings grown on normal medium. On the basis of these results, we speculated that xanthine-derived metabolites might affect both seedling growth and early senescence in cotyledons. To confirm this, seedlings were grown with exogenous xanthine to analyze the role of xanthine-derived metabolites under N deficient condition. Seedlings with xanthine as the sole N-source grew faster, and more cotyledon chlorophyll was broken down, compared with seedlings grown without xanthine. The expression levels of senescence- and purine metabolism-related genes in cotyledons were higher than those in seedlings grown without xanthine. These results indicate the possibility that xanthine plays a role as an activator in both purine catabolism and chlorophyll degradation in cotyledons under N deficient condition.

Structural Identification using Stochastic Filtering Techniques Based on Measurements from Wireless Data Acquisition System

Myungjin Chung,Tadanobu Sato 한국강구조학회 2006 International Journal of Steel Structures Vol.6 No.5

identification using stochastic filtering techniques. The wireless data acquisition system is possible to transmit the digital signalsof the observed structural responses. The validity of the developed structural identification instrument is verified by conductingshaking table test of a model structure. The wireles data acquisition system is set up to a five stories model building and theabsolute acceleration at each story is measured. The Kalman filter and Monte Carlo filter techniques are applied to identifyidentifications of system parameters obtained from both techniques for the model structure, the convergences of identificationresults from Monte Carlo filter are beter than those from Kalman filter.

EXPANSIVE WAVELET-BASED APPROACHES FOR SATELLITE IMAGE FUSION

Myungjin CHOI 한국산업응용수학회 2005 한국산업응용수학회 학술대회 논문집 Vol.- No.-

A useful technique in various applications of remote sensing involves the fusion of panchromatic and multispectral satellite images. Recently, some studies showed that a wavelet-based image fusion method provides high quality spectral content in fused images. However, most decimated wavelet-based methods yield fused results with spatial resolution that is less than that obtained via the intensity-hue-saturation (IHS) fusion technique. In this paper, we introduce three types of the expansive wavelet-based image fusion - the undecimated wavelet-based image fusion, the dual-tree complex wavelet-based image fusion, and the framelet-based image fusion - to increase the spatial resolution of fused result. These methods provide a fused result with both high spatial and spectral resolution. I have been used to merge IKONOS and Landsat ETM+ panchromatic and multispectral images.

User-Interfaced Guidance Scheme for Steering Swarm of magnetic nanoparticles

Myungjin Park,Jungwon Yoon 제어로봇시스템학회 2021 제어로봇시스템학회 국제학술대회 논문집 Vol.2021 No.10

Magnetic Targeted Drug Delivery (MTDD) is a method to steer and concentrate magnetic nanoparticles (MNPs) at a desired location in body. Despite recent developments in magnetic navigation, only few comprehensive strategies for swarm of nanoparticles steering under dynamic fluid exists. This paper introduces a strategy for swarm of MNPs steering in a vascular network under dynamic fluid. In the proposed scheme, user steer aggregated particles to desired location in the MTDD simulator. The properties of aggregated particles are determined by experiment study. After, guidance process is done, guidance scheme which is generated by user is downloaded directly to real system. Effectiveness and feasibility of guidance scheme is demonstrated via simulation and experiment using 1μm diameter MNPs (SiMAG-Silanol 1101 of Chemicell Company) in a 1mm co-diameter Y-shaped channel. We have performed simulation studies with different fluid velocity (1mm/s, 5mm/s, 20mm/s and 100mm/s) and in-vitro studies at 5mm/s. Through both studies, we can demonstrate the potential of swarm of nanoparticles steering under the dynamic fluid. The proposed guidance method enables us to more accurately steer aggregated nanoparticles, improve targeting performance and can easily be extended to complex vessel model.

Binocular Visual Rehabilitation in Paralytic Strabismus by Botulinum A Toxin Chemodenervation

Myungjin Kim,Helen Lew 대한안과학회 2022 Korean Journal of Ophthalmology Vol.36 No.1

Purpose: To investigate the effect of botulinum A toxin (BTXA) chemodenervation in paralytic strabismus patients withoutsurgical correction. Methods: A retrospective chart review of 51 patients who were diagnosed as paralytic strabismus and underwent BTXA chemodenervationwas performed. The patients were divided into four groups according to the cause of paralytic strabismus ofvasculopathy, neoplasm, trauma, and idiopathic. They were also divided into two groups of early and late treatment accordingto the initiation time of BTXA chemodenervation after the onset of strabismus (3 months), and of the initial strabismustype of exotropia and esotropia. We investigated the changes of angle of deviation and diplopia after BTXA chemodenervation. Results: The average deviation of angles decreased by 25.2 prism diopter (PD) (35.1 to 9.9 PD) in total patients, and the overallsuccess rate was 64.7% (33 by 51), and the there was no statistically significant difference in success rate between eachgroup divided by the cause of paralytic strabismus. According to the treatment timing, the deviation of the angle decreasedby 28.0 PD (36.8 to 8.8 PD) in the early treatment group, and 21.3 PD (33.5 to 12.2 PD) in late treatment group at the time ofthe last postinjective follow-up. According to the initial strabismus type, the average angle of deviation decreased by 20.3 PD(35.6 to 15.3 PD) in exotropia group by cranial nerve 3 palsy, and 24.4 PD (32.5 to 8.1 PD) in esotropia by cranial nerve 6 palsy. Conclusions: BTXA chemodenervation reduced the angle of deviation and the number of patients with diplopia regardless ofthe cause of paralytic strabismus. Early BTXA chemodenervation can be considered as the first treatment of choice in paralyticstrabismus, especially in esotropia patients.

S-192 Prevalence and predictors of mortality with Stress induced Cardiomyopathy in critically ill patients

( Myungjin Song ),( Jisoo Choi ),( Bora Yoon ),( Ah Young Leem ),( Joo Han Song ),( Song Yee Kim ),( Eun Young Kim ),( Ji Ye Jung ),( Young Sam Kim ),( Se Kyu Kim ),( Joon Chang ),( Moo Suk Park ) 대한내과학회 2016 대한내과학회 추계학술대회 Vol.2016 No.1

Purpose:?The aims of this study were to assess frequency of stress induced cardiomyopathy (SCMP) and predictors for incidence of SCMP in patients who admitted to medical ICU. We also explored the predictors of in-hospital mortality in patients with SCMP.?Method:?It is a retrospective cohort study. A total of 338 patients admitted to medical ICU and underwent transthoracic echocardiography (TTE) between January 2015 and December 2015 were enrolled. Definition of SCMP was defines as follows: 1) transient hypokinesis, akinesis of the left ventricular mid segments with or without apical involvement or the regional wall motion abnormalities extend beyond a single epicardial vascular distribution; 2) absence of obstructive coronary disease; 3) new EKG abnormalities or modest elevation in cardiac troponin; 4) absence of pheochromocytoma, myocarditis. Logistic regression model was used to analysis predictors for incidence of SCMP and predictors of in-hospital mortality in SCMP respectively. Cox regression model was used to analysis the influence of SCMP to mortality.?Results:?Of the 338 patients, SCMP was observed in 42 patients (12.4%). Compared to 296 patients without SCMP, patients with SCMP had lower frequency of DM (19% vs 29.2%, p=0.01), COPD (4.8% vs 16.9%, p=0.04) and higher prevalence of using mechanical ventilator (MV, 90.5% vs 71.9%, p=0.03), and lower ejection fraction (EF, 38.0±15.6 vs 61.7±11.8, p<0.001). In multivariate analysis, lower BMI (odd ratio, 0.88; 95% CI, 0.78 to 0.99; p=0.04) and lower EF (odd ratio, 0.90; 95% CI, 0.87 to 0.92; p<0.01) were associated with development of SCMP. In a Cox regression model adjusted with several confounders (age, DM, malignancy, liver cirrhosis, shock, acute kidney injury, use of MV) SCMP showed trend to increase of 60-day mortality (p=0.052). Among 42 patients with SCMP, acute kidney injury(AKI) was the only risk factor for predicting in-hospital mortality (odd ratio, 8.19; 95% CI, 1.35 to 47.75; p=0.02).?Conclusions:?Our study showed that prevalence of SCMP was 12.4% and trend to increase of 60-day mortality of critically ill patients. In patients with SCMP, AKI was the only risk factor for predicting in-hospital mortality.

VISUAL CURVATURE FOR SPACE CURVES

( Myungjin Jeon ) 호남수학회 2015 호남수학학술지 Vol.37 No.4

For a smooth plane curve, the curvature can be characterized by the rate of change of the angle between the tangent vector and a fixed vector. In this article we prove that the curvature of a space curve can also be given by the rate of change of the locally defined angle between the tangent vector at a point and the nearby point. By using height functions, we introduce turning angle of a space curve and characterize the curvature by the rate of change of the turning angle. The main advantage of the turning angle is that it can be used to characterize the curvature of discrete curves. For this purpose, we introduce a discrete turning angle and a discrete curvature called visual curvature for space curves. We can show that the visual curvature is an approximation of curvature for smooth curves.