• The Korean Journal of Nuclear Medicine
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• v.32 no.4
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• pp.332-343
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• 1998

Purpose: The purpose of this study was to assess the diagnostic accuracy of various quantitation methods using F-18-fluorodeoxyglucose (FDG) in patients with malignant or benign lung lesion. Materials and Methods: 22 patients (13 malignant including 5 bronchoalverolar cell cancer; 9 benign lesions including 1 hamartoma and 8 active inflammation) were studied after overnight fasting. We performed dynamic PET imaging for 56 min after injection of 370 MBq (10 mCi) of FDG. Standardized uptake values normalized to patient's body weight and plasma glucose concentration (SUVglu) were calculated. The uptake rate constant of FDG and glucose metabolic rate were quantified using Patlak graphical analysis (Kpat and MRpat), three compartment-five parameter model (K5p, MR5p), and six parameter model taking into account heterogeneity of tumor tissue (K6p, MR6p). Areas under receiver operating characteristic curves (ROC) were calculated for each method. Results: There was no significant difference of rate constant or glucose metabolic rate measured by various quantitation methods between malignant and benign lesions. The area under ROC curve were 0.73 for SUVglu, 0.66 for Kpat, 0.77 for MRpat, 0.71 for K5p, 0.73 for MR5p, 0.70 for K6p, and 0.78 for MR6p. No significant difference of area under the ROC curve between these methods was observed except the area between Kpat vs. MRpat (p<0.05). Conclusion: Quantitative methods did not improve diagnostic accuracy in comparison with nonkinetic methods. However, the clinical utility of these methods needs to be evaluated further in patients with low pretest likelihood of active inflammation or bronchoalveolar cell carcinoma.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.3
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• pp.64-70
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• 2016

The recent development of modern weapon system by SOS (System of System) has required users to have more exact decision making. It is possible to achieve the control of complex weapon system more efficiently and effectively by increasing usability. Accordingly, many studies on graphical display have been conducted for several years in the field of HCI (Human Computer Interaction) and GUI (Graphic User Interface), starting from its design stage. Therefore, this paper focuses on evaluating the system GUI usability and analyzing several important points based on performance model, which is a tool for the evaluation and the improvement of service quality. Performance Model, the main focus of this study, reflects user expectations (which is defined as user importance in this paper). The study consists of four steps. First, 34 checklists are drawn from the existing studies related to GUI usability evaluation by using a heuristic method, and then the checklists are matched with 11 weapon system design factors. Next, the study evaluates the importance of GUI element and the usability of weapon system "A" with the checklists twice respectively. Third, the performance of user importance ($P_i$) and the performance of usability ($P_u$) are calculated by modifying a numerical formula for normalization in this step. Finally, the study compares the approach it takes and the existing usability evaluation method, demonstrating that there is a significant difference between the two methods as a result. In addition, 4 improvement factors are suggested for weapon system "A" as "Shortcut" and "Description of Abbreviation," and so on. Although it is necessary to conduct more studies for higher reliability and validity of the results, this study is meaningful considering it takes a new point of view.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1364-1373
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• 2015

The purpose of this study was to determine the optimum sodium concentration (0~8%), soaking time (4~20 min) and storage time (0~60 day) for preparation of persimmon jangachi with kochujang sauce using response surface methodology. Physicochemical properties (salinity, pH, Hunter's color value, cutting force, and sensory evaluation) of persimmon kochujang jangachi were analyzed during storage at $20^{\circ}C$ for 60 days. When the proximate composition of persimmon was analyzed, moisture content, crude protein content, crude lipid content, and crude ash content were 85.41%, 0.51%, 0.22%, and 0.20%, respectively. For persimmon kochujang jangachi manufactured with different sodium concentrations, soaking times, and storage times, salinity, pH, Hunter's color value of L, a, and b, color, flavor, taste, texture, and overall preference were represented by a quadratic model. Cutting force was represented by a linear model pattern. In conclusion, the optimal formulation for persimmon kochujang jangachi, as assessed by numerical and graphical optimization methods, was a sodium concentration of 6.91%, soaking time of 11.36 minutes, and storage time of 25.18 days.

• The Korean Journal of Pesticide Science
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• v.12 no.2
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• pp.111-117
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• 2008

The comparative molecular field analysis (CoMFA) for the fungicidal activity with N-phenylbenzenesulfonamide analogues (1-45) against gray mold (Botriyts cinerea) were studied quantitatively. The statistical values of CoMFA models had much better predictability and fitness than those of comparative molecular similarity indices analysis (CoMSIA) models. The statistical values of the optimized CoMFA I model were predictablity, $r^2_{cv.}(or\;q^2)=0.457$ and correlation coefficient, $r^2_{ncv.}=0.959$, and their fungicidal activity was dependent on the steric field (52%) and electrostatic field (35.6%) of the substrate molecules. And also, it was found that the optimized CoMFA I model with the sensitivity to perturbation ($d_q^{2'}/dr^2_{yy'}=0.898$) and prediction ($q^2=0.346$ & SDEP=0.614) produced by a progressive scrambling analysis was not dependent on chance correlation. From the results of graphical analyses on the contour maps with the optimized CoMFA I model, it is expected that the $R_3$ and $R_4$-substituents on the N-phenyl ring as steric favor group and para-substituents ($R_1$) on the S-phenyl ring as steric disfavor group will contribute to the fungicidal activity. Therefore, the optimized CoMFA I model should be applicable to the prediction of the fungicidal activities against gray mold.

• The Transactions of the Korea Information Processing Society
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• v.2 no.4
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• pp.567-580
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• 1995

A transition-based Objet-oriented programming system(TOPS) is a transition-based object-oriented system suitable for development of various concurrent systems.A TOPS consists of a collection of interacting structural active objects(SAOs),and their behaviors are determined by the transition statements provided in their class definitions.Furthermore,SAOs can be structurally and hierarchcally composed from their component SAOs like hardware commponents. These features allow SAOs to model components for circuit simulation more naturally than passive objects used in ordinary object-oriented programming. Also,we can easily add new kinds of components by using the inheritance mechanism.Executions of transition statements may be eventand/or time-driven, and hence digital,and mixed-mode simulation is possible.Prototype simulation programs with graphical user interfaces have been developed as TOPS progrms for digital,analog,and mixed-mode circuit simulation.

• Journal of Families and Better Life
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• v.27 no.3
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• pp.93-114
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• 2009

The purposes of the study were to find the characteristics of spousal conflict, the characteristics of the origin of family in couple, the intervention techniques of the family therapist, and the processes of change in couple through family therapy. The total family counseling was 9 sessions, which included individual and couple therapy. The study used constant comparative analysis by using open coding method to find the factors. The study suggested the whole model for the study, which could be shown the processes of family therapy in this case study, by using graphical network display. The results of study showed the personal characteristics of husband and wife, the characteristics of the origin of family in couple, the intervention techniques of the family therapist, and the processes of change in husband through family therapy by using matrix. The results revealed that there were many differences in characteristics to cause spousal conflicts and characteriscts in family of origin to influence the crisis of divorce. The therapeutic intervention to treat the couples in the crisis of divorce were facilitation of communication between husband and wife, husband's differentiation of self from family of origin, and understanding about the perspectives of family members. As results of therapeutic intervention, there were showed the spousal change of recognition to each other, husband's differentiation of self, wife's growth of self, and improvement of communication.

• Communications for Statistical Applications and Methods
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• v.19 no.3
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• pp.433-450
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• 2012

As a worker performs a certain operation repeatedly, he tends to become familiar with the job and complete it in a very short time. That means that the efficiency is improved due to his accumulated knowledge, experience and skill in regards to the operation. Investing time in an output is reduced by repeating any operation. This phenomenon is referred to as the learning curve effect. A learning curve is a graphical representation of the changing rate of learning. According to previous literature, learning curve effects are determined by subjective pre-assigned factors. In this study, we propose a new statistical model to clarify the learning curve effect by means of a basic cumulative distribution function. This work mainly focuses on the statistical modeling of binary data. We employ the Newton-Raphson method for the estimation and Delta method for the construction of confidence intervals. We also perform a real data analysis.

• Fire Science and Engineering
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• v.33 no.6
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• pp.20-27
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• 2019

In this study, a new function with higher accuracy for fire heat release rate prediction was developed. The 'αt²' curve, which is the major exponential function currently used for fire engineering calculations, must be improved to minimize the prediction gap that causes fire system engineering inefficiency and lower cost-effectiveness. The newly developed prediction function was designed to cover the initial fire stage that features rapid growth based on logistic function theory, which has a more logical background and graphical similarity compared to conventional exponential function methods for 'αt²'. The new function developed in this study showed apparently higher prediction accuracy over wider range of fire growth durations. With the progress of fire growth pattern studies, the results presented herein will contribute towards more effective fire protection engineering.

• Journal of Digital Convergence
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• v.13 no.11
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• pp.331-336
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• 2015

The texture mapping used for the low-polygon models is one of the important workflows in the graphical representation of the 3D game. Only one hand painted texture is mapped on the surface of the 3D model and represents the color of the material and visual sense of touching by itself in that process. In the 3D game graphics, it is very important to visualize the textile sensation such as protruding and denting. It can be interpreted by the Gestalt Law to recognize a plane as a 3D sense of volume. Moreover, the concept of Affordance is necessary to recognize and perceive the textile sensation. It means visual recognizing of that relationship in the learning process. In this paper, The questionnaire survey targeting 3D game graphic designers is carried out. By analyzing the survey results, we suggest the important characteristic in the process of making hand painted texture.

• The Journal of the Acoustical Society of Korea
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• v.23 no.1
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• pp.17-23
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• 2004

The mobile radio channel can be simulated as a complex-valued random process with narrow-band spectrum. This paper describes a real-time implementation of that process using a INS320C6414 digital signal processor and XC2VP30 Virtex FPGA. The simulator presented here is not only a comprehensive model of the flat fading but also frequency selective fading mobile channel conditions. To replicate the statistical characteristics of the multipath fading environment with the minimum computational burden, multi-rate techniques are employed to resolve practical problems such as variable sampling rate. The simulator produces accurate and consistent results due to digital implementation. It is very flexible and simple to program for various field conditions in mobile communications with a graphical user interface.