• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1754-1758
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• 2014

The nucleophilic substitution reactions of bis(Y-aryl) chlorothiophosphates (1) with X-pyridines are investigated kinetically in acetonitrile at $35.0^{\circ}C$. The free energy relationships with both X and Y are biphasic concave upwards with a break point at X = 3-Ph and Y = H, respectively. The sign of cross-interaction constants (CICs; ${\rho}_{XY}$) is positive with all X and Y. Proposed mechanism is a stepwise process with a rate-limiting leaving group departure from the intermediate with all X and Y. The kinetic results of 1 are compared with those of Y-aryl phenyl chlorothiophosphates (2). In the case of Y = electron-withdrawing groups, the cross-interaction between Y and Y, due to additional substituent Y, is significant enough to change the sign of ${\rho}_{XY}$ from negative with 2 to positive with 1, indicative of the change of mechanism from a rate-limiting bond formation to bond breaking.

• 대한세포병리학회지
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• 제6권2호
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• pp.140-147
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• 1995

In a six-year period (1988. 5-1994. 4), fine needle aspiration cytology(FNAC) of 322 pulmonary lesions from 296 patients were performed at Soonchunhyang University Hospital. Of these 322, malignancy was diagnosed cytologically in 139(43.2%), suspicious malignancy in 7(2.2%), negative in 164(50.8%), and insufficient material in 12(3.8%). Malignant lesions consisted of 54 cases of adenocarcinoma, 50 cases of squamous cell carcinoma, 18 cases of small cell carcinoma. They were verified by histologic examination in 70 cases. There were 2(0.6%) false positive cases due to florid bronchoalveolar hyperplasia and atypical bronchial epithelial cells associated with granulomatous lesion. The overall accuracy rate was 90%, the sensitivity 84.3% and the specificity 94.7%.

• 대한수의학회지
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• 제34권4호
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• pp.815-819
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• 1994

Sixty eight wild rats, Rattus norvegicus, were caught from Seoul city, Kyonggi, Kangwon, Cholla, and Kyongsang-provinces. All sera collected from rats were examined by immunofluorescent test to find antibody against murine typhus. The antibody prevalance to murine typhus was 4.4%(3/68). Sero-positive rate was 12.5%(2/16) in Kyonggi province and 12.5%(1/8) in Cholla province. The sero-positive rate difference between sexes of rats was not recognized. Three Rattus norvegicus having antibody to murine typhus were morphologically classified as subadult with 8.3%(1/12), middle-aged adult with 5.9%(1/17), and old adult with 4.8%(1/21), respectively.

• 대한의용생체공학회:의공학회지
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• 제11권2호
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• pp.209-216
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• 1990

Pulmonary nodules in chest X-Ray images were detected using the symmetric property of human lung and its performance was evaluated. Thls algorithm reduced the effect of background components and enhanced the nodule signals relatively. The image was divided and processed separately, the half with matched filter only, and the other half with warping and matched filter. This algorithm increased the entire detection rate by reducing False-Positive error and improving True-Positive detectability. Result shows 10-25 % improvement in detection rate compared with the conventional alsorithm for nodules size of 10mm.

• Journal of Chest Surgery
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• 제26권11호
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• pp.871-873
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• 1993

Bronchiectasis is an irreversible dilatation that may require surgery for successful treatment. We compared High Resolutional Computed Tomography[HRCT]with Bronchography to access the utility of HRCT in diagnosis and determining the extent of Bronchiectasis. We performed a comparative study of HRCT and Bronchography in 10 consecutive patients who were clinically suspected Bronchiectasis were investigated prospectively during last year.A segment-by-segment analysis of the presence, extent, type of bronchiectasis by Amashita classification was done. In 26 segments, Results of HRCT and Bronchogram were both positve, and 119 segments were both negative.But 15 segments were discorded, in 11 segments in positive bronchogram were negative in HRCT and 4 segments in positive HRCT were negative in bronchogram. The diagnostic concordance rate between 2 modalities was 90.6%[145/160]. So, we will be tried to elevate of concordance rate between 2 modalties and applied HRCT in diagnotic tool for bronchiectasis.

• Journal of Information Processing Systems
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• 제15권6호
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• pp.1265-1276
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• 2019

Data deduplication is a common method to improve cloud storage efficiency and save network communication bandwidth, but it also brings a series of problems such as privacy disclosure and dictionary attacks. This paper proposes a secure deduplication scheme for cloud storage based on Bloom filter, and dynamically extends the standard Bloom filter. A public dynamic Bloom filter array (PDBFA) is constructed, which improves the efficiency of ownership proof, realizes the fast detection of duplicate data blocks and reduces the false positive rate of the system. In addition, in the process of file encryption and upload, the convergent key is encrypted twice, which can effectively prevent violent dictionary attacks. The experimental results show that the PDBFA scheme has the characteristics of low computational overhead and low false positive rate.

• Clinical and Experimental Reproductive Medicine
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• 제17권2호
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• pp.153-158
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• 1990

Sera from 95 infertile males males were assayed for antisperm antibodies using the Tray Agglutination Test(TAT) and indirect Immunobead Test(IBT). The correlation between antisperm antibodies and seminal analysis in infertile men was evaluated, and the TAT was compared with new indirect IBT. The results were obtained as follows. 1. Positive rate for antisperm antibodies was high in azoospermia, oligoasthenospermia, pyo-spermia, in order, Especially in obstructive azoospermia, the rate was the highest in both methods 2. Positive rates for antisperm antibodies in TAT was higher than indirect IBT. 3. Among the isotypes of the immunoglobulins, IgG were most prevalent. IgG and IgA were bound predominantly to the head and IgM predominantly to the tail up.

• 한국환경보건학회지
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• 제26권4호
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• pp.115-121
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• 2000

To evaluate the cytotoxicity of cadmium compounds, this study was conducted to measure the in vitro magnetometry, LDH release and cellular apoptosis using alveolar macrophages of hamsters. A series of magnetometric measurements in cadmium-added groups showed a significant dose-dependent decay of the relaxation curves. The LDH release rates showed a dose-dependently increasing tendency as the dose gradually increased. The positive rates of apoptosis were significantly higher in cadmium-added groups than the control groups. Conclusively, the cytotoxicity increased in a dose dependent way as the concentration of cadmium added increased, which reflected in the decay of relaxation curve in magnetometry, and increased LDH release rate and positive rate of apoptosis.

• Kyungpook Mathematical Journal
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• 제58권4호
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• pp.733-746
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• 2018

The concept of f-statistical convergence which is, in fact, a generalization of statistical convergence, has been introduced recently by Aizpuru et al. (Quaest. Math. 37: 525-530, 2014). The main object of this paper is to prove an f-statistical analog of the classical Korovkin type approximation theorem of Boyanov and Veselinov. It is shown that the f-statistical analog is intermediate between the classical theorem and its statistical analog. As an application, we estimate the rate of f-statistical convergence of the sequence of positive linear operators defined from $C^*[0,{\infty})$ into itself.

• 호남수학학술지
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• 제44권2호
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• pp.281-295
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• 2022

This paper deals with the long - time behavior of global bounded solutions for a non-autonomous dispersive-dissipative equation with time-dependent nonlinear damping terms under the null Dirichlet boundary condition. By a new Lyapunov functional and Łojasiewicz-Simon inequality, we show that any global bounded solution converges to a steady state and get the rate of convergence as well, which depends on the decay of the non-autonomous term g(x, t), when damping coefficients are integral positive and positive-negative, respectively.