• Journal of Korea Society of Industrial Information Systems
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• v.6 no.4
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• pp.54-60
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• 2001

In this thesis, We analyze performance evaluation of one channel B-WLL IF receiver system. Among the item of receiver performance, inter-modulation interference and yield analysis is especially focused. Since inter-modulation interference cause bad influence on system performance due to unwanted third order harmonic located in desired frequency band, third order harmonic causing inter-modulation interference should be efficiently removed. Yield analysis is observing influence on system performance when system element parameter is statistically varied, and in this thesis, system output is observed for LNA parameters. Additionally, Scheme for LNA gain adjustment to reduce inter-modulation interference is proposed by observing variation of third order harmonic output for LNA gain variation.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3755-3760
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• 2012

Single crystals of lithium potassium phthalate (LiKP) were successfully grown from aqueous solution by solvent evaporation technique. The grown crystals were characterized by single crystal X-ray diffraction. The lithium potassium phthalate $C_{16}\;H_{12}\;K\;Li_3\;O_{11}$ belongs to triclinic system with the following unit-cell dimensions at 298(2) K;$a=7.405(5){\AA}$;$b=9.878(5){\AA}$;$c=13.396(5){\AA}$;${\alpha}=71.778(5)^{\circ}$;${\beta}=87.300(5)^{\circ}$;${\gamma}=85.405(5)^{\circ}$; having a space group P1. Mass spectrometric analysis provides the molecular weight of the compound and possible ways of fragmentations occurs in the compound. Thermal stability of the crystal was also studied by both simultaneous TGA/DTA analyses. The UV-Vis-NIR spectrum shows a good transparency in the whole of Visible and as well as in the near IR range. Third order nonlinear optical studies have also been studied by Z-scan technique. Nonlinear absorption and nonlinear refractive index were found out and the third order bulk susceptibility of compound was also estimated. The results have been discussed in detail.

• Korean Journal of Remote Sensing
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• v.19 no.2
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• pp.149-157
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• 2003

In this study, for efficient replacement of sensor modelling of high-resolution satellite imagery, image segmentation method is applied to the test area of the SPOT-3 satellite imagery. After that, a third-order polynomial model in the sectioned area is compared with the RFM which Is to the entire in the test area. As results, plane error of the third-order polynomial model is lower(approximately 0.8m) than that of RFM. On the other hand, height error of RFM is lower(approximately 1.0m).

• Steel and Composite Structures
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• v.39 no.1
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• pp.1-20
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• 2021

An exact solution based on refined third-order theory (TOT) has been presented for functionally graded porous curved beams having deep curvature. The displacement field of the refined TOT is derived by imposing the shear free conditions at the outer and inner surfaces of curved beams. The properties of the two phase composite are tailored according the power law rule and the effective properties are computed using Mori-Tanaka homogenization scheme. The equations of motion as well as consistent boundary conditions are derived using the Hamilton's principle. The curved beam stiffness coefficients (A, B, D) are obtained numerically using six-point Gauss integration scheme without compromising the accuracy due to deepness (1 + z/R) terms. The porosity has been modeled assuming symmetric (even) as well as asymmetric (uneven) distributions across the cross section of curved beam. The programming has been performed in MATLAB and is validated with the results available in the literature as well as 2D finite element model developed in ABAQUS. The effect of inclusion of 1 + z/R terms is studied for deflection, stresses and natural frequencies for FG curved beams of different radii of curvature. Results presented in this work will be useful for comparison of future studies.

• Steel and Composite Structures
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• v.49 no.6
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• pp.633-643
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• 2023

In this study, the natural frequencies of Functional Graded Materials (FGM) plates are predicted using Artificial Neural Network (ANN). A model based on Third-order Shear Deformation Theory (TSDT) and FEM is used to train the ANN model. Different training methods are tested to simulate input and output dependency. As this is a parametric model, several architectures and optimization algorithms were tested. The proposed model allows us to minimize the CPU time to evaluate candidate material properties for FGM plate material selection and demonstrate their influence on dynamic behavior. Consequently, the time required for the FGM design process (candidate materials for material selection) and the geometric optimization of the FGM structure would remain reasonable. The ANN model can help industries to produce FGM plates with good mechanical properties of the selected materials. I addition, this model can be used to directly predict vibration behavior by testing a large number of FGM plates, representing all possible combinations of metals and ceramics in today's industry, without having to solve any eigenvalue problems.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.4
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• pp.912-923
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• 2015

In the results of analyzing Korean corrective action for what are required to be improved according to EU listing Korea as yellow-card non-cooperating third countries against IUU fishing, in order to establish advanced fishery order, it is thought that the following additional improvements are required. (1) The introduction of integrated management system of fishing vessel sailing route, fishing activity, fish catch, and inshore fishing vessel must be considered. (2) It is necessary to establish a system to cross check catch transaction, catch landing, and fish catch report submitted by fishing vessel. (3) Catch transshipment approval system shall be introduced. And a system of reporting and checking catch transshipment at sea shall be reinforced. (4) Punishment shall be strengthened to the extent of making people to perceive that loss due to punishment is larger than profit made from illegal fishing. (5) It shall be so improved that more than a certain percentage of all vessels with fish and fish products caught in waters outside Korea's judicial waters shall be arbitrarily chosen and searched besides a case of being suspected to be IUU fishing. In conclusion, on being listed by EU as yellow-card non-cooperating third countries against IUU fishing, Korean fishery management system shall be generally reexamined, and it shall serve as an occasion to exterminate IUU fishing and to advance fishery management system.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.4
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• pp.323-330
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• 2005

In order to increase reliability and reduce system cost, this paper studies particularly applicable method for sensorless PM BLDCM drive system. The waveform of the motor internal voltages(or back emf) contains a fundamental and higher order frequency harmonics. Therefore the third harmonic component is extracted from the stator phase voltage. The resulting third harmonic signal keeps a constant phase relationship with the rotor flux for any motor speed and load condition, and is practically free of noise that can be introduced by the inverter switching, making this a robust sensing method. In addition, a simple starting method and a speed estimation approach are also proposed. Some experimental results are Provided to demonstrate the validity of the proposed control method.

• Food Science of Animal Resources
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• v.39 no.2
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• pp.222-228
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• 2019

This research was motivated by our encounter with the situation where an optimization was done based on statistically non-significant models having poor fits. Such a situation took place in a research to optimize manufacturing conditions for improving storage stability of coffee-supplemented milk beverage by using response surface methodology, where two responses are $Y_1$=particle size and $Y_2$=zeta-potential, two factors are $F_1$=speed of primary homogenization (rpm) and $F_2$=concentration of emulsifier (%), and the optimization objective is to simultaneously minimize $Y_1$ and maximize $Y_2$. For response surface analysis, practically, the second-order polynomial model is almost solely used. But, there exists the cases in which the second-order model fails to provide a good fit, to which remedies are seldom known to researchers. Thus, as an alternative to a failed second-order model, we present the heterogeneous third-order model, which can be used when the experimental plan is a two-factor central composite design having -1, 0, and 1 as the coded levels of factors. And, for multi-response optimization, we suggest a modified desirability function technique. Using these two methods, we have obtained statistical models with improved fits and multi-response optimization results with the predictions better than those in the previous research. Our predicted optimum combination of conditions is ($F_1$, $F_2$)=(5,000, 0.295), which is different from the previous combination. This research is expected to help improve the quality of response surface analysis in experimental sciences including food science of animal resources.

• International Commerce and Information Review
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• v.11 no.1
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• pp.117-137
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• 2009

Although the third-party logistics are activated and researched in many ways in the advanced countries, China is still on the beginning phase of the third-party logistics and has announced few studies on them. Especially, the study on factors affecting formation for partnership between shippers and third-party logistics providers has never been announced in China, and few empirical studies on them have been done. In order to verify established hypothesis, the empirical analysis is conducted as follows. Totally 500 copies of questionnaire were drawn up and distributed. Amid them 160 copies were collected, finally 155 copies were used for this study as valid samples. The questionnaire used nominal scale and 5 Likert scale. Statistics of collected data were under the data coding process, and analyzed by applying SEM program.

• Journal of Society of Preventive Korean Medicine
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• v.5 no.1
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• pp.10-30
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• 2001

Oriental medicine needs to be armed with theories on health-improvement concept under it and basic data matching its views, in order to participate in the health-improvement service in industrial work places. The Orient medicine health-improvement program defines factors that determine individuals' lifestyle, and provides information and technologies for workers to practice in life. To that end, this research compares and analyzes health-improvement concept and health care, defines relations between individuals' health state and their lifestyle as the basic data needed to perform health-improvement business for workers. 1. The subjects employed for this research is categorized into; by gender, males 52.1% and females 47.9% with no big difference between them; and by age, 20s, 6.1%, 30s. 33.9%, 40s, 34.1%, and 50s, 24.8% with 30-50 accounting for most of it. By marriage status, unmarried represents 7.1%, and married 79.1% with most of them married; by revenue, under one million won represents 3.0%, 1-2 million won 26.4%, 2-2.49 million won 11.2%, above 2.5 million won 11.2%, and 1-2.5 million won a majority. By living location, owned houses represents 65.4%, rented houses 14.7%, monthly-rented 9.5%; and by education, elementary and middle school represent 16.9%, high school and its dropouts 22.6%, and junior college and higher 51.6%, with high school and higher occupying most of the group. 2. By job, office workers and managerial workers represent 12.3%, part-timers 21.0%, manual workers 11.4%, jobless 0.6%, professionals 35.6%, service 0.6%, housewives 8.4%, and equipment/machinery operation/assemblers 10.1%. Of this, jobless and part-timers, totaling three, are dropped from this research. By years worked, 0-3.9 years represents 9.7%, 4-7.9 years 6.7%, 8-14.9 years 18.4%, above 15 years 28.7%, and no respondents 36.5%. 3. The degree of the subjects practicing life-improvement lifestyle, on a scale of 1 to 4, is an average of 2.69, personal relations 3.04, self-realization 2.92, stress management 2.76, nutritional state 2.73, responsibility for health 2.47, and athletic activities 2.18, with personal relations earning the highest points and athletic activities the lowest. As for factors influencing health-improvement lifestyle, there is no significant difference between gender, age, and marriage status. Meanwhile, there is significant difference between revenue, dwelling pattern, education level, etc. That is, higher income-bracket, owned houses, rented houses, monthly-rented houses, and higher-educated, in this order, show higher average in health-enhancement lifestyle. By job, housewives, manual workers, office workers, professionals, equipment/ machinery operation/ assemblers, and part-timers, in this order show higher points, while there is no difference with significance by years worked. 4. Factors that affect health-improvement lifestyle are shown below. Self-realization is influenced by age, marriage status, type of dwellings, and level of education; responsibility for health by type of dwellings; athletic activities by gender and age; nutrition by age, marriage status and type of dwellings; personal relations by marriage status; and stress management by type of dwellings. 5. Areas with high points by job show this: in self-realization, office workers, manual workers, housewives, professionals, equipment/ machinery operation/ assemblers, in this order, show difference with significance; in the area of responsibility for health, manual workers, housewives, equipment/ machinery operation/ assemblers, professionals, office workers and part-timers, in this order, do. In athletic activities, manual workers, housewives, office workers, professionals, equipment/ machinery operation/ assemblers, and part-timers, in this order, show difference with significance; in nutrition, housewives, office workers, manual workers, professionals, equipment/ machinery operation/ assemblers, and part-timers, in this order do; and in stress, housewives, office workers, manual workers, professionals, equipment/ machinery operation/ assemblers, part-timers, in this order do. By years worked, more years showed higher points in the area of responsibility for health and nutrition; in the area of athletic activities, above 15 years, 4-8 years, below 4 years and 8-14 years, in this order, show higher points; and no difference shows in realization, personal relation, and stress area. 6. To look at correlation between overall and divisional health-improvement practice degree, this researcher has analyzed it using Person's correlation coefficient. Self-realization, responsibility for health, athletic activities, nutrition, support for personal relations, and stress management show significant correlation with the sub-divisions, while all health-improvement lifestyle shows significant correlation with the six sub-divisions.