• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.3
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• pp.213-232
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• 2009

This document was prepared to review and summarize the analytical methods for airborne and bulk asbestos. Basic principles, shortcomings and advantages for asbestos analytical instruments using phase contrast microscopy(PCM), polarized light microscopy(PLM), X-ray diffractometer (XRD), transmission electron microscopy(TEM), scanning electron microscopy(SEM) were reviewed. Both PCM and PLM are principal instrument for airborne and bulk asbestos analysis, respectively. If needed, analytical electron microscopy is employed to confirm asbestos identification. PCM is used originally for workplace airborne asbestos fiber and its application has been expanded to measure airborne fiber. Shortcoming of PCM is that it cannot differentiate true asbestos from non asbestos fiber form and its low resolution limit ($0.2{\sim}0.25{\mu}m$). The measurement of airborne asbestos fiber can be performed by EPA's Asbestos Hazard Emergency Response Act (AHERA) method, World Health Organization (WHO) method, International Standard Organization (ISO) 10312 method, Japan's Environmental Asbestos Monitoring method, and Standard method of Indoor Air Quality of Korea. The measurement of airborne asbestos fiber in workplace can be performed by National Institute for Occupational Safety and Health (NIOSH) 7400 method, NIOSH 7402 method, Occupational Safety and Health Administration (OSHA) ID-160 method, UK's Health and Safety Executive(HSE) Methods for the determination of hazardous substances (MDHS) 39/4 method and Korea Occupational Safety and Health Agency (KOSHA) CODE-A-1-2004 method of Korea. To analyze the bulk asbestos, stereo microscope (SM) and PLM is required by EPA -600/R-93/116 method. Most bulk asbestos can be identified by SM and PLM but one limitation of PLM is that it can not see very thin fiber (i.e., < $0.25{\mu}m$). Bulk asbestos analytical methods, including EPA-600/M4-82-020, EPA-600/R-93/116, OSHA ID-191, Laboratory approval program of New York were reviewed. Also, analytical methods for asbestos in soil, dust, water were briefly discussed. Analytical electron microscope, a transmission electron microscope equipped with selected area electron diffraction (SAED) and energy dispersive X-ray analyser(EDXA), has been known to be better to identify asbestiform than scanning electron microscope(SEM). Though there is no standard SEM procedures, SEM is known to be more suitable to analyze long, thin fiber and more cost-effective. Field emission scanning electron microscope (FE-SEM) imaging protocol was developed to identify asbestos fiber. Although many asbestos analytical methods are available, there is no method that can be applied to all type of samples. In order to detect asbestos with confidence, all advantages and disadvantages of each instrument and method for given sample should be considered.

• Journal of the Korean Society of Tobacco Science
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• v.21 no.2
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• pp.109-118
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• 1999

A model predicted describing the effect of cigarette making materials on the level of filter ventilation was developed and evaluated. The developed model was expressed in terms of a linear and quadratic relationship which was validated with experimental measurements for different porosity of plug wrap and tipping paper, unencapsulated pressure drop of filter plug and cigarette column and vent position. Forty-six experimental frequencies were determined as a result of using three levels with five factors Box-Behnken design and analyzed by the multiple regression analysis with backward stepwise in STATISTICA/PC under restricted conditions. The four factors, except filter pressure drop variable, were statistically significant at the level of 0.05 but most of all linear by linear interactions were comparatively lower significant. By the analysis of linear and quadratic regression coefficient, filter ventilation of the cigarette was affected by porosity of plugwrap (5.87, -4.25), porosity of tip paper (5.68, -1.00), vent position (-3.87, 3.08), tobacco column pressure drop (2.56, 0.66), and filter pressure drop (1.50, 0.58) in the decreasing order. It should be emphasized that the major conclusion of this study was not that any particular parameter was linear or quadratic on any limit scale, but that there were highly significant relationships among factors involving linear, quadratic and their interaction and perhaps even linearity between and within factors. While, there is also quite strong evidence that vent position from mouth end and cigarette making materials are reverse relationship on this experimental model. On the basis of the result, it can be concluded that the porosity of the plug wrap and tipping paper has a marked effect on degree of filter ventilation rate. The F-value of plug wrap and tipping paper porosity among five factors were 39.2 and 36.8 respectively with P-value of 0.000 indicating higher significant for both factors. According to the analysis of variance, the model fitted for filter ventilation was significant at 5% confidence level and the coefficient of determination ($R^2$=0.84) was the proportion to variability in the data well fitted for by the model.

• Korean Journal of Veterinary Research
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• v.44 no.1
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• pp.49-55
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• 2004

The present study was carried out to investigate the potential acute toxicity of CKD-602 by a single intravenous dose in Beagle dogs. The test chemical was administered intravenously to male and female Beagle dogs at dose levels of 0.3, 0.5, or 2.5 mg/kg. Mortalities, clinical findings, and body weight changes were monitored for the 14-day period following the administration. At the end of 14-day observation period, all animals were sacrificed and complete gross postmortem examinations were performed. All males and females of the 2.5 mg/kg dose group were found dead between the fourth and seventh day after the injection. Treatment related clinical signs, including vomiting, anorexia, mucous stool, diarrhea, and no stool were observed. Decrease or suppression of body weight was observed in a dose-dependent manner. In autopsy, dark red discoloration of the gastrointestinal tract, atrophy of the thymus, paleness of the spleen, sporadic dark red spots of the lung and petechia of the heart were observed in dead animals of the 2.5 mg/kg dose group. There were no specific adverse effects on males and females of the 0.3 and 0.5 mg/kg dose groups, except for the transient clinical signs such as anorexia, vomiting, and mucus/no stool. On the basis of the results, it was concluded that a single intravenous injection of CKD-602 to Beagle dogs resulted in increased incidence of abnormal clinical signs and death, decreased body weight, and increased incidence of abnormal gross findings. The absolute toxic dose of this chemical was 2.5 mg/kg for both genders. The $LD_{50}$ value was 1.1 mg/kg (95% confidence limit not specified) for both genders. The no-observed-effect level (NOEL) was considered to be below 0.3 mg/kg for both genders.

• Journal of Chest Surgery
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• v.53 no.3
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• pp.104-113
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• 2020

Background: Accurate intraoperative assessment of mediastinal lymph nodes is a critical aspect of lung cancer surgery. The efficacy and potential for upstaging implicit in these dissections must therefore be revisited in the current era of uniportal video-assisted thoracoscopic surgery (VATS). Methods: A retrospective study was conducted in which 544 patients with stage I (T1abc-T2a, N0, M0) primary lung cancer were analyzed. To assess risk factors for nodal upstaging and to limit any imbalance imposed by surgical choices, we constructed an inverse probability of treatment-weighted (IPTW) logistic regression model (in addition to non-weighted logistic models). We also evaluated risk factors for early locoregional recurrence using IPTW logistic regression analysis. Results: In the comparison of uniportal and multiportal VATS, the resected lymph node count (14.03±8.02 vs. 14.41±7.41, respectively; p=0.48) and rate of nodal upstaging (6.5% vs. 8.7%, respectively; p=0.51) appeared similar. Predictors of nodal upstaging included tumor size (odds ratio [OR], 1.74; 95% confidence interval [CI], 1.12-2.70), carcinoembryonic antigen level (OR, 1.11; 95% CI, 1.04-1.18), and histologically confirmed pleural invasion (OR, 3.97; 95% CI, 1.89-8.34). The risk factors for locoregional recurrence within 1 year were found to be number of resected N2 nodes, age, and nodal upstaging. Conclusion: Uniportal and multiportal VATS appear similar with regard to accuracy and thoroughness, showing no significant difference in the extent of nodal dissection.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.3
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• pp.75-83
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• 1984

The probability of failure is used to analyze the reliability of three dimensional slope failure, instead of conventional factor of safety. The strength parameters are assumed to be normal variated and beta variated. These are interval estimated under the specified confidence level and maximum likelihood estimation. The pseudonormal and beta random variables are generated using the uniform probability transformation method according to central limit theorem and rejection method. By means of a Monte-Carlo Simulation, the probability of failure is defined as; $P_f=M/N$ N: Total number of trials M: Total number of failures Some of the conclusions derived. from the case study include; 1. Three dimensional factors of safety are generally much higher than 2-D factors of safety. However situations appear to exist where the 3-D factor of safety can be lower than the 2-D factor of safety. 2. The $F_3/F_2$ ratio appears to be quite sensitive to c and ${\phi}$ and to the shape of the 3-D shear surface and the slope but not to be to the unit weight of soil. 3. From the two models (normal, beta) considered for the distribution of the factor of safety, the beta distribution generally provides lager than normal distribution. 4. Results obtained using the beta and normal models are presented in a nomgraph relating slope height and slop angle to probability of failure.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.8
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• pp.1197-1205
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• 2006

This experiment was conducted to compare the effects of feeding DL-2-hydroxy-4-(methylthio)butanoic acid (HMTBA) and DL-methionine (DLM) supplemented corn-soybean-cottonseed meal diets on growth performance, carcass composition, and muscle color of broilers. The trial was designed as a $2{\times}3{\times}2$ factorial experiment, including two methionine (Met) sources (HMTBA and DLM), three equimolar graded levels of Met supplementation (i.e., 0.08, 0.16, and 0.24% in the starter diet and 0.07, 0.14, and 0.21% in the grower and finisher diets, respectively), and two sexes (male and female). Additionally, one basal diet for each sex was formulated to be limiting in Met to test the dosage response of increasing supplemental Met levels. Four hundred and twenty 10-d-old broilers were randomly allotted to 14 treatments (seven each for males and females), with five replicate pens per treatment and six chicks per pen. There was no difference (p>0.05) between the two Met sources in growth performance and muscle deposition of broilers throughout the whole experimental period (d 10 to 49). With the increasing Met supplementation levels, average daily gain was increased (quadratic; p<0.01) during the starter, grower, and overall phases, average daily feed intake was increased (quadratic; p<0.01) during the starter phase, and feed:gain ratio was decreased (quadratic; p<0.05) during the grower and overall phases. At the end of finisher phase, Met supplementation increased breast muscle content (quadratic; p<0.01) and thigh muscle content (linear; p<0.05), and decreased abdominal fat content (quadratic; p<0.02). Compared to the broiler fed DLM, broilers fed HMTBA had superior breast and thigh muscle coloration (p<0.01). Male broilers had higher weight gain and feed intake and better feed conversion than female broilers (p<0.01). The fat content of thigh muscle in female broilers was higher than that of male broilers (p<0.03). The best fit comparison of HMTBA vs. DLM was determined by Schwarz Bayesian Criteria index, which indicated that the average relative bioefficacy of HMTBA vs. DLM was 120% with 95% confidence limit 67 to 172%. These results indicated that Met supplementation improved growth performance and carcass quality of broilers fed corn-soybean-cottonseed meal diets irrespective of Met sources. Compared to DLM, HMTBA has the same molar bioefficacy on improving the growth performance and carcass quality of broilers; however, HMTBA fed birds had superior meat color to DLM fed birds.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.1
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• pp.85-96
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• 2018

Objectives This study was performed to compare the electrical methods of motor points mapping using surface EMG and electric probe (Pointer Excel II). Methods 32 healthy adults (male 16, female 16) were selected. and classified into two groups; surface EMG group, electric probe (Pointer Excel II) group. In surface EMG group, motor points were searched by recoding the compound muscle potentials. In electric probe (Pointer Excel II) group, motor points were searched by scanning the skin with Pointer Excel II at low level stimulation. The locations of the motor points were expressed as X and Y values in relation to the reference line. The horizontal reference line was set as elbow crease and the vertical reference line was set as the line connecting coracoid process to the center of the horizontal reference line. The data was analyzed by 'Independent T-test' and 'equivalence test'. Results 1. The motor points of short head and long head of biceps brachii muscle were located at about 2/3 length of the vertical reference line from coracoid process and about 1/5~1/4 length of the half of the horizontal reference line from the vertical reference line in both group. 2. The motor points of the short head were located more distally and close to the vertical reference line (p<0.001). 3. In surface EMG group, the motor points of the long head were located more laterally in the female than male. And the motor points of the long head were located more distally in the left side than right side (p<0.05). In electric probe (Pointer Excel II) group, similar tendency was observed but there was no statistically significant difference (p>0.05). 4. As a result of the equivalence test between surface EMG group and electric probe (Pointer Excel II) group, the confidence intervals of the difference were within the equivalence limit. Therefore, the locations of the motor points searched by two ways are equa l (p>0.05, equivalence interval=3%). Conclusions The results indicate that electric probe (Pointer Excel II) can be used to search the motor points instead of surface EMG. This might improve the clinical efficiency when using the motor points to treat muscle dysfunction.

• Journal of Korea Water Resources Association
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• v.41 no.8
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• pp.807-823
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• 2008

This paper presents a technique for estimating discharge rating curve parameters. In typical practical applications, the original non-linear rating curve is transformed into a simple linear regression model by log-transforming the measurement without examining the effect of log transformation. The model of pseudo-likelihood estimation is developed in this study to deal with heteroscedasticity of residuals in the original non-linear model. The parameters of rating curves and variance functions of errors are simultaneously estimated by the pseudo-likelihood estimation(P-LE) method. Simulated annealing, a global optimization technique, is adapted to minimize the log likelihood of the weighted residuals. The P-LE model was then applied to a hypothetical site where stage-discharge data were generated by incorporating various errors. Results of the P-LE model show reduced error values and narrower confidence intervals than those of the common log-transform linear least squares(LT-LR) model. Also, the limit of water levels for segmentation of discharge rating curve is estimated in the process of P-LE using the Heaviside function. Finally, model performance of the conventional log-transformed linear regression and the developed model, P-LE are computed and compared. After statistical simulation, the developed method is then applied to the real data sets from 5 gauge stations in the Geum River basin. It can be suggested that this developed strategy is applied to real sites to successfully determine weights taking into account error distributions from the observed discharge data.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.132-138
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• 2012

Existing network layer firewall security support is one that does not support the higher layer, the application layer of a vulnerable web application security. Under these circumstances, the vulnerability of web applications to be able to defend a Web Application Firewall is positioned as a solver to solve the important security issues of businesses spotlighted in the next generation of security systems, and a very active market in the market other than domestic is expected to be formed. However, Firewall Web has not yet proposed a standard which can be used to test the performance of the Web Application Firewall Web Application Firewall and select the products of trust hardly Companies in BMT conduct their own individual problems and the cost of performance testing technologies, there is a limit. In this study, practically usable BMT model was developed to evaluate the firewall vendor. Product ratings ISO / IEC 9126, eight product characteristics meet the performance and characteristics of a web application firewall entries are derived. This can relieve the burden on the need to be evaluated in its performance testing of Web firewall, and can enhance the competitiveness of domestic-related sectors, by restoring confidence in the product can reduce the dependence on foreign products.

• Analytical Science and Technology
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• v.23 no.3
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• pp.240-246
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• 2010

A technique for the determination of trace Cu(II) in various real samples by FAAS after the column preconcentration onto p-dichlorobenzene-SA adsorbent, which is microcrystalline p-dichlorobenzene loaded with salicylaldoxime (SA) has been developed. Several experimental conditions such as pH of the sample solution, the amount of chelating agent salicylaldoxime, the amount of adsorbent p-dichlorobenzene-SA, and flow rate of sample solution were optimized. The interfering effects of various concomitant ions were investigated. $CN^-$ interfered more seriously than any other ions. However, the interference by $1\;{\mu}g\;mL^{-1}\;CN^-$ could be overcome completely by controlling the concentration of Ni(II) to $20\;{\mu}g\;mL^{-1}$. The linear range, correlation coefficient ($R^2$) and detection limit obtained by this technique were $3.0\sim100\;ng\;mL^{-1}$, 0.9901, and $3.1\;ng\;mL^{-1}$, respectively. For validating this technique, the aqueous samples (wastewater, reservoir water and stream water) and the food samples (orange juice, fresh egg and skim milk) were used. Recovery yields of 93~104% were obtained. These measured mean values were not differents from ICP-MS data at 95% confidence level. The good results were obtained from the experiments using the rice flour certified reference material (CRM) sample. Based on the experimental results, it was found that this technique could be applied to the preconcentration and determination of Cu(II) for various real samples.