• Horticultural Science & Technology
• /
• v.30 no.5
• /
• pp.557-567
• /
• 2012

This study was conducted to achieve basal information for the development of tomato cultivars with disease resistances through marker-assisted backcross (MAB). Ten inbred lines with TYLCV, late blight, bacterial wilt, or powdery mildew resistance and four adapted inbred lines with superior horticultural traits were collected, which can be useful as the donor parents and recurrent parents in MAB, respectively. Inbred lines collected were evaluated by molecular markers and bioassay for confirming their disease resistances. To develop DNA markers for selecting recurrent parent genome (background selection) in MAB, a total of 108 simple sequence repeat (SSR) primer sets (nine per chromosome at average) were selected from the tomato reference genetic maps posted on SOL Genomics Network. Genetic similarity and relationships among the inbred lines were assessed using a total of 303 polymorphic SSR markers. Similarity coefficient ranged from 0.33 to 0.80; the highest similarity coefficient (0.80) was found between bacterial wilt-resistant donor lines '10BA333' and '10BA424', and the lowest (0.33) between a late blight resistant-wild species L3708 (S. pimpinelliforium L.) and '10BA424'. UPGMA analysis grouped the inbred lines into three clusters based on the similarity coefficient 0.58. Most of the donor lines of the same resistance were closely related, indicating the possibility that these lines were developed using a common resistance source. Parent combinations (donor parent ${\times}$ recurrent parent) showing appropriate levels of genetic distance and SSR marker polymorphism for MAB were selected based on the dendrogram. These combinations included 'TYR1' ${\times}$ 'RPL1' for TYLCV, '10BA333' or '10BA424' ${\times}$ 'RPL2' for bacterial wilt, and 'KNU12' ${\times}$ 'AV107-4' or 'RPL2' for powdery mildew. For late blight, the wild species resistant line 'L3708' was distantly related to all recurrent parental lines, and a suitable parent combination for MAB was 'L3708' ${\times}$ 'AV107-4', which showed a similarity coefficient of 0.41 and 45 polymorphic SSR markers.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.23 no.4
• /
• pp.247-255
• /
• 2018

This paper proposes a transformer design of a direct cell-to-cell active cell balancing circuit with a multi-winding transformer for battery management system (BMS) applications. The coupling coefficient of the multi-winding transformer and the output capacitance of MOSFETs significantly affect the balancing current transfer efficiency of the cell balancing operation. During the operation, the multi-winding transformer stores the energy charged in a specific source cell and subsequently transfers this energy to the target cell. However, the leakage inductance of the multi-winding transformer and the output capacitance of the MOSFET induce an abnormal energy transfer to the non-target cells, thereby degrading the transfer efficiency of the balancing current in each cell balancing operation. The impacts of the balancing current transfer efficiency deterioration are analyzed and a transformer design methodology that considers the coupling coefficient is proposed to enhance the transfer efficiency of the balancing current. The efficiency improvements resulting from the selection of an appropriate coupling coefficient are verified by conducting a simulation and experiment with a 1 W prototype cell balancing circuit.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2008.11a
• /
• pp.137-140
• /
• 2008

If the flexural member of concrete is designed using the FRP rebar, suddenly brittleness destruction resulted from the fracture of FRP rebar is generated in the extreme situation because of brittleness characteristics of FRP rebar and concrete when designed to be less than balanced reinforcement ratio, so it is recommended to design the flexural member of concrete to be more than balanced reinforcement ratio. In ACI 440.1R-06 proposes the different bending strength decrease coefficient according to destructive form of concrete flexural member using the FRP rebar. However, ACI 440.1R-06 applies the same strength decrease coeffient to all FRP rebars made of diverse materials. If the same strength decrease coefficient is applied to all FRP rebars, effect of increasing the reinforcement ratio and selection of FRP rebar will be considerably limited. In this regard, we are to propose the formula to calculate the bending strength decrease coefficient in consideration of change in characteristics of FRP rebar and L/D through the reliability analysis in this paper.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.17 no.5
• /
• pp.25-33
• /
• 2017

NOMA (Non-orthogonal multiple access) system becoming a strong candidate for 5G cellular system of its high spectral efficiency. This paper considers an optimal power allocation scheme to minimize the outage probability of a user relay based cooperative NOMA system. We first derive the outage probabilities of the relay user (RU) and the destination user (DU) with selection combining. Based on these probabilities, the outage probability of the cooperative NOMA system is obtained. The analytical results are verified by Monte Carlo simulation. It is noticed that the outage probability of cooperative NOMA system has a convex function, the optimum power allocation coefficient, which satisfied the minimum outage probability, is calculated. Numerical examples show that the optimal power allocation coefficient increases with the required capacity of DU. While the capacity of DU is fixed, we noticed that the increase of the required capacity of RU decreases the optimal power allocation coefficient.

• Journal of radiological science and technology
• /
• v.44 no.4
• /
• pp.389-397
• /
• 2021

The purpose of this study was to compare the demographic and job characteristics and job satisfaction of sonographers (SONO) and radiological technologists (RT). The subjects were a total of 148 people (69 SONO, 79 RT), who had been working in clinical and hospitals. The method was conducted using a questionnaire with a total of 54 questions consisting of demographic characteristics, job characteristics, and job satisfaction. Reliability was secured with Cronbach's alpha coefficient of 0.6 or higher for the response of the questionnaire. For statistical analysis, descriptive statistics, cross-analysis, independent sample T-test, and correlation analysis using Pearson's correlation coefficient and Spearman's correlation coefficient were performed for each occupation. As a result, first, the SONO had more female workers than RT. They are more than three times as many in graduate school and above. Second, the SONO had 4.5 times more morning shift than the RT and no form of weekend shift. Third, the average monthly salary of the SONO is higher than that of the RT, but when a certain portion of the salary goes up, the salary no longer goes up. Fourth, satisfaction with expectations, growth desire, positive mentality, growth opportunity, job importance, organizational attachment was higher SONO than the RT, but self-efficacy was higher in RT than SONO. Last, SONO had higher educational background than RT. It is hoped that the results of this study will be able to understand the job characteristics of SONO and RT and identify the factors of job satisfaction and provide them as fundamental materials for job selection.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.23 no.5
• /
• pp.103-108
• /
• 2023

In this paper, a performance enhancement study of an AESA antenna that can be applied to a seeker that serves as the eye of a missile was conducted, and the performance of the antenna was verified through actual measurement. When designing an AESA antenna, the optimization of the active reflection coefficient must be considered during transmission due to the mutual coupling between radiators that inevitably occurs, and the selection of a radiator that can overcome the space limitation of the seeker with a small size/light weight is an important design consideration. Accordingly, optimization in terms of electrical performance and low-profile structure is required through research on array antennas for application to the AESA structure. The radiator designed and measured in this paper was designed as an SFN that can satisfy the low-profile structure while enhancing the performance of a general vivaldi antenna. Through this paper, it was confirmed that SFN has the same broadband characteristics as general vivaldi antennas and has optimized characteristics required for AESA antennas. The structure optimized through simulation confirmed the pattern characteristics and active reflection coefficient characteristics through the fabrication of actual proto-type antennas.

• Journal of Korean Academy of Nursing
• /
• v.39 no.6
• /
• pp.818-828
• /
• 2009

Purpose: This study was done to develop a cell phone addiction scale for Korean adolescents. Methods: The process included construction of a conceptual framework, generation of initial items, verification of content validity, selection of secondary items, preliminary study, and extraction of final items. The participants were 577 adolescents in two middle schools and three high schools. Item analysis, factor analysis, criterion related validity, and internal consistency were used to analyze the data. Results: Twenty items were selected for the final scale, and categorized into 3 factors explaining 55.45% of total variance. The factors were labeled as withdrawal/tolerance (7 items), life dysfunction (6 items), and compulsion/persistence (7 items). The scores for the scale were significantly correlated with self-control, impulsiveness, and cell phone use. Cronbach's alpha coefficient for the 20 items was .92. Scale scores identified students as cell phone addicted, heavy users, or average users. Conclusion: The above findings indicate that the cell phone addiction scale has good validity and reliability when used with Korean adolescents.

• 유체기계공업학회:학술대회논문집
• /
• 2002.12a
• /
• pp.408-416
• /
• 2002

Hydraulic performance of the pump with an inducer was predicted by 3-D Navier-stokes calculation. The evaluated pump was the single-stage centrifugal pump with a separated inducer to pressurize fuel (LCH4) in Turbo-pump system with a specific speed (Ns) of approximately 0.3[rad/s, m3/s, J/kg] and a suction specific speed(s) of 15[rad/s, m3/s, J/kg]. That conventional pump was designed with the combination of 1-D theory and empirical correlation. In this study, preliminary design to select key parameters such as inlet flow coefficient was reviewed by investigating sets of the known design methods to achieve appropriate suction performance, and the performance of newly designed inducer and impeller was compared with the old one, using CFD method. The numerical results showed that the hydraulic efficiency of the new pump was predicted $5.5\%$ higher than that of the conventional one, through design parameter re-selection, configuration improvement and blade loading control

• Journal of Environmental Health Sciences
• /
• v.22 no.1
• /
• pp.99-106
• /
• 1996

The purpose of this study is to observe a specific removal efficiency of synthethetic wastewater which is managed by upflow submerged type at porous media which was sinteringed on a comparative low temperature 600$\circ$C, was annexed slag and humus soil with main material kaolinite. Observing removal efficiency quality of each media, a mixed media of kaolinite and humus soil by gravity percent 60, 40% respectively showed the most excellent removal utility, and applied predictive models for suspended culture kinetics without consideration diffusion limitation, and when analyzed kinetic which had been processed by this study the removal efficiency accompanied by carbon, nitrogen, phosphorous volumetric loading rate variation standed for a comparative large change rate 61~71%, it means the selection of the most proper load factor had a great effect on the highly removal efficiency, yield coefficient(Y) and specific microbial attach equation showed 1.53 mgVSS/mgCOD, $m_p=10039.4\times ((S_0)/(6.75+S_0))$ repectively.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.6
• /
• pp.1819-1826
• /
• 1996

This paper present the claculating method of optimum correction mass within permissible vibration linits for ratating machinery in two-plane field balancing. Basic technique of this method is based on influence coefficient method, and grphic vector composition that the resultant of two influence vectors obtained by trial mass have to be equilibrium with initial vibration vector in the each correction plane. Genetic algorithm which is a search algorithm based on the mechanism of natural selection and natural genetics is sued for vector composition, and SUMT method is used to objective function which seeks optimum correction mass for balancing a rotor.