• Transactions on Electrical and Electronic Materials
• /
• v.13 no.5
• /
• pp.225-228
• /
• 2012

In order to synthesize LED phosphor materials, we have applied three novel synthesis techniques, "melt synthesis", "fluidized bed synthesis" and "vapor-solid hybrid synthesis", in contrast with the conventional solid state reaction technique. These synthesis techniques are also a general and powerful tool for rapid screening and improvements of new phosphor materials.

• Advances in nano research
• /
• v.13 no.5
• /
• pp.437-451
• /
• 2022

Synthesis approaches usually affect the physical and chemical properties of ferrites. This helps ferrite materials to design them for desired applications. Some of these methods are mechanical milling, ultrasonic method, micro-emulsion, co-precipitation, thermal decomposition, hydrothermal, microwave-assisted, sol-gel, etc. These methods are extensively reviewed by taking example of ZnFe₂O₄. These methods also affect the microstructure and local structure of ferrite which ultimately affect the physical and chemical properties of ferrites. Various spectroscopic techniques such as Raman spectroscopy, Fourier Transform Infrared spectroscopy, Ultra Violet-Visible spectroscopy, Mossbauer spectroscopy, extended x-ray absorption fine structure, and electron paramagnetic resonance are found helpful to reveal this information. Hence, the basic principle and the usefulness of these techniques to find out appropriate information in ZnFe₂O₄ nanoparticles is elaborated in this review.

• ETRI Journal
• /
• v.42 no.4
• /
• pp.527-533
• /
• 2020

High-level synthesis (HLS), which automatically synthesizes a register-transfer level (RTL) circuit from a behavioral description written in a high-level programming language such as C/C++, is becoming a more popular technique for improving design productivity. In general, HLS tools often generate a circuit with a larger area than those of hand-designed ones. One reason for this issue is that HLS tools often generate multiple instances of the same module from a function. To eliminate such a redundancy in circuit area in HLS, HLS tools are capable of sharing modules. Function-level module sharing at a behavioral description written in a high-level programming language may promote function reuse to increase effectiveness and reduce circuit area. In this paper, we present two HLS techniques for module sharing at the function level.

• Advances in nano research
• /
• v.2 no.2
• /
• pp.89-98
• /
• 2014

A novel and simple method for the synthesis of nano-magnetite particles is disclosed. In the novel procedure, $Fe^{2+}$ is the only source of metal cation. Carboxymethylcellulose (CMC) is used as the structure directing agent. The phase analysis of the nano-particles was performed using XRD and electron diffraction techniques. Size and morphology analysis was performed using light scattering and TEM techniques. The effect of $NH_4OH$ solution (32 wt. %) at different CMC concentrations on the size distribution of the final magnetite powders is studied. An optimal base concentration exists for each CMC concentration leading to minimal agglomeration. There exists a minimum CMC concentration (0.0016 wt. %), lower than that no magnetite forms. It is shown that using the new method, it is possible to immobilize a lipase enzyme (Candida Rugosa) with immobilization efficiency larger than 98 % with a loading more than 3 times the reported value in the literature. The latter phenomenon is explained based on the agglomerate state of the nano-particles in the liquid phase.

• The Journal of the Acoustical Society of Korea
• /
• v.18 no.1E
• /
• pp.32-36
• /
• 1999

In the area of the speech synthesis techniques, the waveform coding methods maintain the intelligibility and naturalness of synthetic speech. In order to apply the waveform coding techniques to synthesis by rule, we must be able to alter the pitches of synthetic speech. In this paper, we propose a new pitch altering method that compensates phase distortion of the cepstral pitch alteration method with time scaling method in the time domain. This method can remove some spectrum distortion which is occurred in conjunction point between the waveforms. For performance test the spectrum distortion rate was used as objective criterion and the MOS(Mean Opinion Score) was used as subjective criterion. As a result, the spectrum distortion and MOS are obtained by 0.66% and 3.9, respectively.

• Journal of the Korean Institute of Telematics and Electronics C
• /
• v.36C no.9
• /
• pp.20-27
• /
• 1999

In many synthesis applications, the structure of the synthesized circuit is derived from its BDD functional representation. When synthesizing incompletely specified functions, it is useful to minimize the size of these BDDs using don't cares. In this paper, we present two BDD minimization heuristics that target these synthesis applications. Experimental results show that new techniques yield significantly smaller BDDs compared to existing techniques with manageable run-times.

• Proceedings of the IEEK Conference
• /
• 1999.06a
• /
• pp.683-686
• /
• 1999

In this paper, we develop an active sonar signal synthesis model to analyze the detection performance of active sonar systems in a shallow water environment. Using this model, we synthesize the return signal of a bistatic sonar system at a typical operating frequency. This signal can be used to test proper active sonar signal processing techniques for real applications.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 1997.04a
• /
• pp.177-184
• /
• 1997

The Component Mode Synthesis Method for the -vibration analysis can be applied to the large-scaled structures, which have difficulty in modeling because of their intricate shapes and boundary conditions and need much time in computational calculations. This paper uses the Component Mode Synthesis Method to analyze the free vibration for the steel box bridge having the large number of D.O.F as an example of the large structural system. By comparing the CMS method to the other method (FEM), this paper proves the accuracy of the solution in techniques and the efficiency in time.

• Archives of Pharmacal Research
• /
• v.27 no.1
• /
• pp.25-30
• /
• 2004

Combinatorial homoserine lactone mixtures and individual products were obtained from the methionine-functionalized resin in solid-phase synthesis. The four-step process consisting of a coupling step of an N-Fmoc-L-methionine, deprotection of N-Fmoc group, N-coupling with a carboxylic acid, and cleavage reaction through a polymer supported strategy is described. Gas chromatography-mass selective detector (GC-MSD) techniques provide the most powerful methods for identifying both the combinatorial mixtures and individual products.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.10a
• /
• pp.464-466
• /
• 2014

The mechanism synthesis methods, graphical, analytical and computer-aided technique have been proposed for selecting and scaling mechanical system. According to developing computation tools, mechanism could be synthesized much faster and more correct than previous analytical ways by improved techniques. In this paper, the improved synthesis method is proposed to solve body guidance synthesis problem. To perform the mechanism synthesis for body guidance, a planar linkage is modeled as a set of free three bushings located in design space. The values of bushing stiffness and x, y position of bushings yielding a desired functional requirement related to input motion are found by using an optimization technique.