• Journal of the Korean Chemical Society
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• v.67 no.4
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• pp.217-221
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• 2023

A series of hydrophobic dodecyl-terminated 6th-generation poly(amidoamine) dendrimer (H)-encapsulated cadmium sulfide ((CdS)_n@H) nanoparticles in a co-solvent (toluene: methanol = 6.8: 3.2 v/v) are synthesized. The diameters of CdS nanoparticles within the dendrimer were estimated by analyzing the positions of the first excitonic absorption peaks of CdS in UV-vis spectra. The size of the CdS nanoparticle within the dendrimer shows a saturation value as the CdS/H ratio (n) increases, which is believed to be due to the limited physical size of the void cavity within the dendrimer. This simple and convenient method of estimating the saturation of the size of CdS in dendrimers may be useful in determining the maximum void space within other dendrimers under various solvent conditions.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.599-601
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• 2022

Due to the increase in the use of smartphones after the 4th industrial revolution, the market size of mobile shopping is growing as mobile shopping using smartphones rather than internet shopping using PCs increases. With the rapid growth of the mobile shopping market, online social commerce and open markets have grown.

• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3866-3873
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• 2023

In 4th^-generation storage rings, whether to operate the beam as round or flat is a critical question. A round beam has equal horizontal and vertical emittances, and is an efficient solution to reduce strong intra-beam scattering effects and lengthen the Touschek lifetimes, but a flat beam produces a brighter photon beam than a round beam. To provide both beams concurrently rather than bifurcating the beam time, this paper presents the exploitation of beam dynamics and the cutting-edge fast pulser that supports concurrent operation of round beam and flat beam.

• ETRI Journal
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• v.36 no.2
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• pp.321-324
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• 2014

This letter describes a two-phase clock oxide thin-film transistor shift register that executes a robust operation over a wide threshold voltage range and clock coupling noises. The proposed circuit employs an additional Q generation block to avoid the clock coupling noise effects. A SMART-SPICE simulation shows that the stable shift register operation is established for the clock coupling noises and the threshold voltage variation from -4 V to 5 V at a line time of $5{\mu}s$. The magnitude of coupling noises on the Q(15) node and Qb(15) node of the 15th stage is respectively -12.6 dB and -26.1 dB at 100 kHz in the proposed circuit, compared to 6.8 dB and 10.9 dB in a conventional one. In addition, the estimated power consumption is 1.74 mW for the proposed 16-stage shift registers at $V_{TH}=-1.56V$, compared to 11.5 mW for the conventional circuits.

• Journal of the Korean Home Economics Association
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• v.41 no.8
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• pp.139-158
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• 2003

This study investigated the effects of Korean parents' family-of-origin experiences, marital conflict, open or dysfunctional communication with their children, children's coping behaviors on their behavior problems as a function of a child's sex. Theoretical models for both sexes were constructed based on the results. Two hundred and nine boys and one hundred and ninety six girls of 4th and 5th grades from two elementary schools filled out the questionnaires to assess their communication with the parents, their problem-focused coping behaviors, and their internalizing and externalizing behavior problems. Four hundred five parents of these children answered the questionnaires to assess differentiation for the family-of-origin and the marital conflict. The results were as follows. Boys' path pattern showed that the fathers' differentiation from the family-of-origin effected their sons' internalizing and externalizing behavior problems through parent-child dysfunctional communication. Girls' path exhibited two different patterns. One is that the mothers' differentiation from the family-of-origin effected their daughters' internalizing and externalizing behavior problems through parent-child dysfunctional communication. Another one is that the mothers' differentiation from the family-of-origin influenced children's internalizing behavior problems through daughters' problem-focused coping behaviors as well as parent-child dysfunctional communication.

• 한국전산유체공학회:학술대회논문집
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• 1995.10a
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• pp.55-63
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• 1995

The flow field around a high-speed train including cross-wind effects has been simulated. This study solves 3-D unsteady incompressible Navier-Stokes equations in the inertial frame using the iterative time marching scheme. The governing equations are differenced with 1st-order accurate backward difference scheme for the time derivatives, 3th-order accurate QUICK scheme for the convective terms and 2nd-order accurate central difference scheme for the viscous terms. The Marker-and-Cell concept was applied to efficiently solve continuity equation, which is differenced with 2nd-order accurate central difference scheme. The 4th-order artificial damping is added to the continuity equation for numerical stability. A C-H type of elliptic grid system is generated around a high-speed train including ground. The Baldwin-Lomax turbulent model was implemented to simulate the turbulent flows. To validate the present procedure, the flow around a high speed train at constant yaw angle of $45^{\circ}\;and\;90^{\circ}$ has been simulated. The simulation shows 3-D vortex generation in the lee corner. The flow separation is also observed around the rear of the train. It has concluded that the results of present study properly agree with physical flow phenomena.

• Journal of the Korean Society of Safety
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• v.29 no.3
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• pp.91-97
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• 2014

This study aims to suggest a measure to reduce industrial accident and secure adaptation to the industrial safety regulation policies by empirically establishing the effects of stress from adaptation to the industrial safety regulation on the human error, one of direct causes of industrial accident to the target groups of the industrial safety regulation policies. This study as for content range examines the stress from adaptation to the industrial safety regulation, job satisfaction, human error, and as for spatial range, this study performed an empirical research on the workers of 24 companies located within Chungcheong region centers district among 153 companies nationwide that uses 7 chemicals by introducing PSM (process safety management) system of the Ministry of Employment & Labor as of January 2012. Based on these results and suggestions there are five(5) necessities to reduce industrial safety regulations adaptation stress and human error generation, first(1st) is the necessity of understanding influential factors to stress, second(2nd) is the necessity to customized vocational training, third(3rd) is improving enhance system of job satisfaction, forth(4th) is preparing stress-reduction program, and fifth(5th) is introducing on-site restrictive action of advanced country as politics items.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.10
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• pp.3299-3312
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• 2022

Recently, South Korea preferentially allocated frequencies to build 5G networks as a core competitiveness of the 4th Industrial Revolution. Although the government recognize the importance of 5G construction and preoccupation, network operators have limited to some services, testing the possibility of practical use of 5G. They hesitated to actively build and to carry out the service of a complete 5G network. While 5G is being developed and standardized like this, no one is sure of this step exactly what 5G will be. Thus, following research questions are asked by various stakeholders of 5G market: What is an ideal service providing method for the practical use of 5th generation mobile network? And what are the critical elements to be considered when selecting the service providing method? Therefore, the study aims to investigate 5G service providing issues and elements to be considered and to provide most appropriate service providing method for the practical use of 5G. The results identify that 'Specialized Service' is most appropriate method at the aspects of benefit and opportunity as well as the aspect of risk. In addition, the outcomes imply that the experts replying to the survey not only expect the expansion of emerging market, but also concern the social risk and cost. Since the study dealt with economic, social and business issues in providing 5G service, it might contribute not only to practical research, but also to academic research regarding 5G service method.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.283-288
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• 2011

Occurrence of Scrobipalpa salinella (Zeller) was investigated on glasswort in Shinan, Jeonnam and Kimjae, Jeonbuk from 2010 to 2011. The occurrence of S. salinella observed four times in a year. Adult stages of S. salinella in two areas occurred from mid-April to late September. The peak times of 1st, 2nd and 3rd generation adults of S. salinella was observed on early May, mid-June, late July (in Kimjae) to early August (in Shinan) and early September, respectively. And larval stages of S. salinella occurred from late May to late August. The peak times of development of 1st, 2nd and 3rd generation larvae of S. salinella was observed on mid-June, mid-July and mid-August, respectively. However, the 4th generation larvae began to occur in mid-September but didn't damage in glasswort. Among the distances from the bank of glasswort field (3, 6, 9 m) and periods of damage (Jun. 16, Jul. 7, Aug. 12), larval density in 3 m distance from the bank in 1st damage season (Jun. 16) was high which resulted to severe damage. Damage of 2nd and 3rd generation larvae was progressed both density of larvae and levels of damage.

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.2
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• pp.81-86
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• 2005

The mode of transmission, effect on fecundity, hatching and tissues specificity of a microsporidian $(Lb_{ms})$ recovered from Lamerin breed of the silkworm Bombyx mori L. was studied and compared with standard strain Nosema bombycis. Peroral inoculation of $Lb_{ms}$ or N. bombycis to zeroday of $4^{th}$ instar larvae of silkworm was the most suitable method for producing information on development of stage specific mortality, pupation and obtaining infected adults for transovarial transmission studies. It was observed that pupal mortality, the percentage of moths emerged and the percentage of moths infected were significantly high in N. bombycis infected batches as compared $(Lb_{ms})$ in all the three tested breeds of the silkworm. However no significant difference was observed in larval mortality. The fecundity and hatchability was not affected significantly in $(Lb_{ms})$ infected adults, however significant reduction in egg production, fecundity, hatchability and increased egg retention was observed in mother moths infected with N. bombycis. The $(Lb_{ms})$ is transmitted both horizontally and vertically at lower rate due to its low rate of proliferation. The trans ovarial transmission of $(Lb_{ms})$ to the $F_1$ progeny generation through eggs averaged only $61.33\pm5.10\%$ whereas N. bombycis was transmitted at $100\%$. The $(Lb_{ms})$ had low oral infectivity and low transovarial transmission in silkworm B. mori.