• Journal of the Korean Ceramic Society
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• v.44 no.9
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• pp.471-476
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• 2007

The hydration mechanism of the $3CaO{\cdot}Al_2O_3-CaSO_4{\cdot}2H_2O$ system in the presence of alkali sulfates has been investigated. The early hydration rate of $3CaO{\cdot}Al_2O_3$ was accelerated by the addition of $Na_2SO_4$ and $K_2SO_4$. This is closely related to the formation of syngenite $(CaSO_4{\cdot}K_2SO_4{\cdot}H_2O)$, and the U-phase added $K_2SO_4$ and $Na_SO_4$ in the $3CaO{\cdot}Al_2O_3-CaSO_4{\cdot}2H_2O$ system, respectively. The formation of the rigid syngenite and U-phase structure led to rapid setting and decreases the sulfate content in the liquid phase of the hydrating cement to the extent that it cannot adequately retard the hydration of $3CaO{\cdot}Al_2O_3$. In case of the alkali sulfate not added to the $3CaO{\cdot}Al_2O_3-CaSO_4{\cdot}2H_2O$ system, the ettringite was transformed to monosulfoaluminate immediately after the consumption of gypsum. However, when the alkali sulfates were added to this system, the ettringite did not transform to monosulfoaluminate immediately even though the gypsum was completely consumed. There was a stagnation period to transform to the monosufoaluminate after the consumption of gypsum because the syngenite and U-phase remained as the sulfate source.

• Journal of Pharmacopuncture
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• v.26 no.3
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• pp.247-256
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• 2023

Objectives: Enterococcus faecalis is a gram positive diplococci, highly versatile and a normal commensal of the gut microbiome. Resistance to vancomycin is a serious issue in various health-care setting exhibited by vancomycin resistant Enterococci (VRE) due to the alteration in the peptidoglycan synthesis pathway. This study is thus aimed to detect the VRE from the patients with root caries from the clinical isolates of E. faecalis and to evaluate the in-silico interactions between vanA and the Aegles marmelos bio-compounds. Methods: E. faecalis was phenotypically characterized from 20 root caries samples and the frequency of vanA and vanB genes was detected by polymerase chain reaction (PCR). Further crude methanolic extracts from the dried leaves of A. marmelos was assessed for its antimicrobial activity. This is followed by the selection of five A. marmelos bio-compounds for the computational approach towards the drug ligand interactions. Results: 12 strains (60%) of E. faecalis was identified from the root caries samples and vanA was detected from two strains (16%). Both the stains showed the presence of vanA and none of the strains possessed vanB. Crude extract of A. marmelos showed promising antibacterial activity against the VRE strains. In-silico analysis of the A. marmelos biocompounds revealed Imperatonin as the best compound with high docking energy (-8.11) and hydrogen bonds with < 140 TPSA (Topological polar surface area) and zero violations. Conclusion: The present study records the VRE strains among the root caries with imperatorin from A. marmelos as a promising drug candidate. However the study requires further experimentation and validation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.1
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• pp.111-122
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• 2014

The provided habitat of many services from natural capital is important. But because most ecosystem services tools qualitatively evaluated biodiversity or habitat quality, this study quantitatively analyzed those aspects using the species distribution model (MaxEnt). This study used location point data of the goat(Naemorhedus caudatus), marten(Martes flavigula), leopard cat(Prionailurus bengalensis), flying squirrel(Pteromys volans aluco) and otter(Lutra lutra) from the 3rd National Ecosystem Survey. Input data utilized DEM, landcover classification maps, Forest-types map and digital topographic maps. This study generated the MaxEnt model, randomly setting 70% of the presences as training data, with the remaining 30% used as test data, and ran five cross-validated replicates for each model. The threshold indicating maximum training sensitivity plus specificity was considered as a more robust approach, so this study used it to conduct the distribution into presence(1)-absence(0) predictions and totalled up a value of 5 times for uncertainty reduction. The test data's ROC curve of endangered mammals was as follows: growing down goat(0.896), otter(0.857), flying squirrel(0.738), marten(0.725), and leopard cat(0.629). This study was divided into two groups based on habitat: the first group consisted of the goat, marten, leopard cat and flying squirrel in the forest; and the second group consisted of the otter in the river. More than 60 percent of endangered mammals' distribution probability were 56.9% in the forest and 12.7% in the river. A future study is needed to conduct other species' distribution modeling exclusive of mammals and to develop a collection method of field survey data.

• Tuberculosis and Respiratory Diseases
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• v.82 no.1
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• pp.15-26
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• 2019

The pathogen Mycobacterium avium complex (MAC) is the most common cause of nontuberculous mycobacterial pulmonary disease worldwide. The decision to initiate long-term antibiotic treatment is difficult for the physician due to inconsistent disease progression and adverse effects associated with the antibiotic treatment. The prognostic factors for the progression of MAC pulmonary disease are low body mass index, poor nutritional status, presence of cavitary lesion(s), extensive disease, and a positive acid-fast bacilli smear. A regimen consisting of macrolides (clarithromycin or azithromycin) with rifampin and ethambutol has been recommended; this regimen significantly improves the treatment of MAC pulmonary disease and should be maintained for at least 12 months after negative sputum culture conversion. However, the rates of default and disease recurrence after treatment completion are still high. Moreover, treatment failure or macrolide resistance can occur, although in some refractory cases, surgical lung resection can improve treatment outcomes. However, surgical resection should be carefully performed in a well-equipped center and be based on a rigorous risk-benefit analysis in a multidisciplinary setting. New therapies, including clofazimine, inhaled amikacin, and bedaquiline, have shown promising results for the treatment of MAC pulmonary disease, especially in patients with treatment failure or macrolide-resistant MAC pulmonary disease. However, further evidence of the efficacy and safety of these new treatment regimens is needed. Also, a new consensus is needed for treatment outcome definitions as widespread use of these definitions could increase the quality of evidence for the treatment of MAC pulmonary disease.

• Journal of Digital Contents Society
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• v.14 no.4
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• pp.455-462
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• 2013

This paper proposes a detection system that, by determining whether a dangerous act is being carried out among other pedestrians in the images captured using CCTV, provides pre-warnings and establishes emergency measures. To determine the presence of a dangerous act, after setting zones of interest and danger zones within those zones of interest, the danger level is determined in accordance with the range of encroachment upon detecting an object. Especially, this research aims at detecting a suicide jump from the bridge and extends to detecting a dangerous act among pedestrians from detecting a dangerous act of only one person with no one in the previous research. This system classifies the status into 3 levels as safe, alert, and danger according to the amount of part being over the bridge railing. If a situation is deemed as warning-worthy and emergency, the integrated control center is immediately alerted to facilitate prevention in advance.

• Tuberculosis and Respiratory Diseases
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• v.66 no.1
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• pp.47-51
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• 2009

Hepatopulmonary syndrome (HPS) is characterized by a defect in arterial oxygenation that's induced by pulmonary vascular dilatation in the setting of liver disease. Some studies have shown the relationship between the presence of the HPS and the severity of liver disease, but there are only rare cases of HPS inpatient with Child-Pugh class A liver cirrhosis. We report here on a case of a 58 years-old male who suffered from progressive dyspnea for the previous few years. He was diagnosed with alcoholic liver cirrhosis 5 years previously. There was no significant abnormality on the chest radiograph and transthoracic echocardiography, but the arterial blood gas analysis revealed severe hypoxemia. Contrast-enhanced transesophageal echocardiograpy with agitated saline demonstrated a delayed appearance of microbubbles in the left cardiac chambers. Thus, he was finally diagnosed with HPS. This case suggests that we should consider HPS when a patient with compensated liver cirrhosis has unexplained dyspnea.

• The Korean Journal of Cytopathology
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• v.18 no.2
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• pp.165-169
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• 2007

The authors present the fine needle aspiration cytology (FNAC) cytologic findings of a case of extranodal marginal zone B cell lymphoma (MZBCL), which featured abundant plasma cells and eosinophilic histiocytes arising in both parotid glands. A 49-year-old female presented with palpable masses in both parotid glands. She had been suffering from systemic lupus erythematosus and rheumatoid arthritis. The lesions were evaluated by FNAC and smears showed a small number of clusters of oncocytic cells with abundant eosinophilic granular cytoplasm and small nuclei, intermixed with small to medium-sized lymphoid cells containing round to lobulated nuclei, which suggested Warthin's tumor. Some of lymphoid cells had a plasmacytoid appearance, and some scattered large cells contained a large amount of eosinophilic cytoplasm. Bilateral superficial parotidectomy was performed and a histopathologic study indicated MZBCL with abundant plasma cells, intermixed with eosinophilic histiocytes. The presence of oncocytic cells and a mixture of lymphoid and plasma cells indicates Warthin's tumor, but the cytologic features of a relatively monotonous small to medium-sized lymphoid infiltrate suggest the possibility of MZBCL in the clinical setting of an FNAC study performed on a patient suffering from a connective tissue disease.

• Journal of Biomedical Engineering Research
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• v.44 no.4
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• pp.255-263
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• 2023

Clinical ultrasound (US) is a widely used imaging modality with various clinical applications. However, capturing a large field of view often requires specialized transducers which have limitations for specific clinical scenarios. Panoramic imaging offers an alternative approach by sequentially aligning image sections acquired from freehand sweeps using a standard transducer. To reconstruct a 3D volume from these 2D sections, an external device can be employed to track the transducer's motion accurately. However, the presence of optical or electrical interferences in a clinical setting often leads to incorrect measurements from such sensors. In this paper, we propose a deep learning (DL) framework that enables the prediction of scan trajectories using only US data, eliminating the need for an external tracking device. Our approach incorporates diverse data types, including correlation volume, optical flow, B-mode images, and rawer data (IQ data). We develop a DL network capable of effectively handling these data types and introduce an attention technique to emphasize crucial local areas for precise trajectory prediction. Through extensive experimentation, we demonstrate the superiority of our proposed method over other DL-based approaches in terms of long trajectory prediction performance. Our findings highlight the potential of employing DL techniques for trajectory estimation in clinical ultrasound, offering a promising alternative for panoramic imaging.

• The Journal of the Acoustical Society of Korea
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• v.40 no.5
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• pp.401-407
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• 2021

The continuous active sonar technology is effective for detecting and tracking targets because of short target revisiting rate. Generalized Sinusoidal Frequency Modulation (GSFM) pulses suitable for continuous active sonar systems are known to be capable of obtaining high time-bandwidth product while maintaining the orthogonality between pulses. However, it is unknown how to calculate an appropriate length of time to correlate received GSFM pulses in the presence of a target with acceleration. In this paper, we propose a method to calculate the appropriate time length based on the correlation when matching the received signal in the continuous active sonar system using GSFM pulse. The proposed method calculates the correlation according to the acceleration of the target and calculates the signal processing length according to the correlation. It is shown that stable detection performance can be obtained when the signal processing length calculated by the proposed method through the level of the sidelobe is applied.

• The Journal of the Acoustical Society of Korea
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• v.26 no.8
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• pp.397-402
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• 2007

In this paper, we apply a support vector machine(SVM) that incorporates an optimized nonlinear decision rule over different sets of feature vectors to improve the performance of statistical model-based voice activity detection(VAD). Conventional method performs VAD through setting up statistical models for each case of speech absence and presence assumption and comparing the geometric mean of the likelihood ratio (LR) for the individual frequency band extracted from input signal with the given threshold. We propose a novel VAD technique based on SVM by treating the LRs computed in each frequency bin as the elements of feature vector to minimize classification error probability instead of the conventional decision rule using geometric mean. As a result of experiments, the performance of SVM-based VAD using the proposed feature has shown better results compared with those of reported VADs in various noise environments.