• Journal of Sensor Science and Technology
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• v.31 no.4
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• pp.228-237
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• 2022

Two-dimensional (2D) nanomaterials have demonstrated the potential to replace silicon and compound semiconductors that are conventionally used in photodetectors. These materials are ultrathin and have superior electrical and optoelectronic properties as well as mechanical flexibility. Consequently, they are particularly advantageous for fabricating high-performance photodetectors that can be used for wearable device applications and Internet of Things technology. Although prototype photodetectors based on single microflakes of 2D materials have demonstrated excellent photoresponsivity across the entire optical spectrum, their practical applications are limited due to the difficulties in scaling up the synthesis process while maintaining the optoelectronic performance. In this review, we discuss facile methods to mass-produce 2D material-based photodetectors based on the exfoliation of van der Waals crystals into nanosheet dispersions. We first introduce the liquid-phase exfoliation process, which has been widely investigated for the scalable fabrication of photodetectors. Solution processing techniques to assemble 2D nanosheets into thin films and the optoelectronic performance of the fabricated devices are also presented. We conclude by discussing the limitations associated with liquid-phase exfoliation and the recent advances made due to the development of the electrochemical exfoliation process with molecular intercalants.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.17 no.1
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• pp.197-207
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• 1987

This study was undertaken to investigate the relationships between film and processing solution at different processing temperatures. Three kinds of periapical film were used for this study. They included EP-2l film, DF-58, and A film Each film was processed by automatic film processor with RD-Ⅲ X-dol 90, and A processing solutions at 68° 74° 80° 86° and 92°F. Film density was measured with the densitometer, and base plus fog density, film relative speed, film contrast, and subject contrast were evaluated. The following results were obtained; 1. As the processing temperature was increased, base plus density was increased. Inadequate base plus fog densities were obtained with three films in combination with three processing solutions at 92°F. 2. Lowest base plus fog densities were obtained with A film, followed in ascending order by EP-21, and DF-58 film in combination with A or RD-Ⅲ processing solutions. The sequence of base plus fog densities was in ascending order by EP-21, A, and DF-58 film in combination with X-dol 90 processing solution. 3. The sequence of film relative speed values was in ascending order of EP-21, A, and DF-58 film in combination with A and RD-Ⅲ processing solutions, respectively. 4. As the processing temperature was increased, film contrast values was increased. The sequence of film contrast values was in descending order solution. The sequence of film contrast values was in descending order of EP-2l, DF-58, and A film in combination with RD-Ⅲ, X-dol 90 processing solution at 80°F. 5. As the processing temperature was increased, subject contrast was increased. The sequence of subject contrast was in descending order of A, X-dol 90, and RD-Ⅲ processing solution in combination with three films at 80°F. The sequence of subject contrast was in descending order of EP-21, A, and DF-58 film in combination with A processing solution at different processing temperatures.

• Applied Chemistry for Engineering
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• v.35 no.1
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• pp.61-65
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• 2024

The effectiveness of CuSCN as a hole injection layer in large-area organic light-emitting diodes, organic solar cells, and thin-film transistors has been well demonstrated. Therefore, in this study, the surface, optical, and electrical analyses of CuSCN were carried out according to the solution process conditions in order to propose optimized film conditions. Various CuSCN solution concentrations were prepared to determine the film surface characteristics and to determine whether the film surface affects the electrical performance of the device. When the CuSCN solution concentration was low, the CuSCN film was not formed and coated in the form of islands, and when the solution concentration was increased, the CuSCN film was formed uniformly, which contributed to improving the conductivity of the device. In addition, a hole-only device was fabricated to demonstrate the role of CuSCN as a hole transport layer.

• Journal of Astronomy and Space Sciences
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• v.20 no.4
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• pp.403-416
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• 2003

There are common features, in both imaging surveys and image processing, between astronomical observations and remote sensing. Handling large amounts of data, in an easy and fast way, has become a common issue. Implementing pipeline software can be a solution to the problem, one which allows the processing of various kinds of data automatically. As a case study, the development of pipeline software for the EIS (European Southern Observatory Imaging Survey) is introduced. The EIS team has been conducting a sky survey to provide candidate targets to the 250 VLTs (Very Large Telescopes) observations. The survey data have been processed in a sequence of five major data corrections and reductions, i.e. preprocessing, flat fielding, photometric and astrometric corrections, source extraction, and coaddition. The processed data are eventually distributed to the users. In order to provide automatic processing of the vast volume of observed data, pipeline software has been developed. Because of the complexity of objects and different characteristic of each process, it was necessary to analyze the whole works of the EIS survey program. The overall tasks of the EIS are identified, and the scheme of the EIS pipeline software is defined. The system structure and the processes are presented, and in-depth flow charts are analyzed. During the analyses, it was revealed that handling the data flow and managing the database are important for the data processing. These analyses may also be applied to many other fields which require image processing.

• Textile Coloration and Finishing
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• v.26 no.4
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• pp.331-338
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• 2014

In this research, split-type complex yarn of 20:80, 40:60, 50:50 nylon6/polyester composition ratio was used in order to impose unique sense on split-type complex woven. After treating both split-type complex yarn of each ratio and its produced woven in alkali solution, we got the following results by checking physical properties based on alkali proportion and treatment time. Under the condition of NaOH 20% in this experiment, it took approximately double time 20% loss of weight. The loss of weight became high when polyester proportion of N/P(nylon6/polyester) composition ratio was low, in the same fineness yarn. Even though polyester proportion was low, the loss of weight was low when the fineness was high. N/P division was well processed at about 25% loss of weight under the condition of NaOH 20%, treatment temperature $50^{\circ}C$, and treatment time 60 minutes. The research provides that the loss of weight should be processed around treatment time 24 hours in the case of NaOH concentration 15%, and treatment time 15 hours in the case of NaOH concentration 18%, respectively, in order to achieve N/P woven division ratio of about 70%-80% in industrial fields.

• Computers and Concrete
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• v.22 no.2
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• pp.183-196
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• 2018

The rheological behaviour of high strength self compacting concrete (HS-SCC) studied through an experimental investigation is presented in this paper. The effect of variation in supplementary cementitious materials (SCM) $vis-{\grave{a}}-vis$ four different types of processed crushed sand as fine aggregates is studied. Apart from the ordinary Portland cement (OPC), the SCMs such as fly ash (FA), ground granulated blast furnace slag (GGBS) ultrafine slag (UFS) and micro-silica (MS) are used in different percentages keeping the mix -paste volume and flow of concrete, constant. The combinations of rheology, strength and durability are equally important for selection of mixes in respect of high-rise building constructions. These combinations are referred to as the rheo-strength and rheo-durability which is scientifically linked to performance based rating. The findings show that the fineness of the sands and types of SCM affects the rheo-strength and rheo-durability performance of HS-SCC. The high amount of fines often seen in fine aggregates contributes to the higher yield stress. Further, the mixes with processed sand is found to offer better rheology as compared to that of mixes made using unwashed crushed sand, washed plaster sand, washed fine natural sand. The micro silica and ultra-fine slag conjunction with washed crushed sand can be a good solution for high rise construction in terms of rheo-strength and rheo-durability performance.

• The Transactions of the Korea Information Processing Society
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• v.6 no.2
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• pp.459-466
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• 1999

I broadband ISDN every packet will show different result if it would be processed according to its usage by the server. That is, normal data won't show big differences if they would be processed at normal speed. But it will improve the quality of service to process some kinds of data - for example real time video or voice type data or some data for a bid to by something through the internet - more fast than the normal type data. solution for this problem was suggested - priority packets. But the analyses of them are under way. Son in this paper a switching system for an output queuing model in a single server was assumed and some packets were given priorities and analysed. And correlation, simulating real life situation, was given too. These packets were analysed through three cases, first packets having no correlation, second packets having only correlation and finally packets having priority three cases, first packets having no correlation, second packets having only correlation and finally packets having priority and correlation. The result showed that correlation doesn't affect the mean delay time and the high priority packets have improved mean delay time regardless of the arrival rate. Those packets were assumed to be fixed-sized like ATM fixed-sized cell and the contention strategy was assumed to be short bus contention method for the output queue, and the mean delay length and the maximum 버퍼 length not to lose any packets were analysed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.288-289
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• 2006

We studied the effect of sol-gel processing and sintering temperature on the microwave properties of $MgCo_2(VO_4)_2$ system(MCV) which is applicable to LTCC(low-temperature cofired ceramics). The MCV was synthesized by sol-gel process using solution that contains precursor molecules for Mg, Co, and V. SEM analysis shows that the average particle size is ${\sim}1{\mu}m$ and size distribution is very uniform compared to the one prepared by conventional solid-state reaction process. Highly dense samples were obtained at the sintering temperature range of $750^{\circ}C{\sim}930^{\circ}C$. The maximum $Q{\times}f_0$ value of 55,700GHz, dielectric constant(${\varepsilon}_r$) of 10.41 and temperature coefficient(${\tau}_f$) of $-85ppm/^{\circ}C$ was obtained at the sintering temperature of $930^{\circ}C$. The superior microwave properties of sol-gel processed MCV relative to conventional solid-state reaction processed one is remarkable especially at lower sintering temperatures such as $750^{\circ}C$ and $800^{\circ}C$.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.8
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• pp.4120-4132
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• 2017

In this research, we implement a deformable object simulation system using OpenGL's shader language, GLSL4.3. Deformable object simulation is implemented by using volumetric mass-spring system suitable for real-time simulation among the methods of deformable object simulation. The compute shader in GLSL 4.3 which helps to access the GPU resources, is used to parallelize the operations of existing deformable object simulation systems. The proposed system is implemented using a compute shader for parallel processing and it includes a bounding box-based collision detection solution. In general, the collision detection is one of severe computing bottlenecks in simulation of multiple deformable objects. In order to validate an efficiency of the system, we performed the experiments using the 3D volumetric objects. We compared the performance of multiple deformable object simulations between CPU and GPU to analyze the effectiveness of parallel processing using GLSL. Moreover, we measured the computation time of bounding box-based collision detection to show that collision detection can be processed in real-time. The experiments using 3D volumetric models with 10K faces showed the GPU-based parallel simulation improves performance by 98% over the CPU-based simulation, and the overall steps including collision detection and rendering could be processed in real-time frame rate of 218.11 FPS.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.7
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• pp.102-108
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• 2013

In manufacturing of solution-processed organic electronic devices, a spin coating method is frequently used, but which has a big problem. Solvent in a solution has a decisive effect such as physical and chemical damage for successive solution-based film deposition. Such a severe damage by solvent restricts for fabricating building blocks of multi-layered films from solutions. In this work, it will be shown that a proper combination of well-known solvents gives a chance to fabricate multi-layered film, also this new method was applied to make organic field effect transistor. Two types of bottom gate, bottom contact transistors were fabricated, one of which is fabricated by conventional single spin coating method, the other fabricated by double spin coating method. Compared with the electrical characteristics in a single spin coated transistor, the leakage current between source and gate electrode was decreased, ON state current was increased, and the extracted saturation mobility was multiplied more than 2.7 time for double spin coated transistors. It is suggested that the multiple coated gate dielectric structure is more desirable for high performance organic ferroelectric field effect transistors.