• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.660-663
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• 2004

Recently in the automotive industries, light and high quality material is strongly required because of emissions regulation issues. In the electromagnetic stirring process, it has many merits that are the exact control ability about material processing and a good point of the protection of environment. In this paper, the morphology of the change of primary Al phase in A356 alloy by electro magnetic stirrer was investigated to obtain the globular structure. The parameters are the current, stirring time, pouring temperature and cooling rate of different wall thickness; 5mm, 15mm, 25mm respectively. By proper selection of the processing parameters, globular primary particles can be obtained by electromagnetic stirrer.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.3
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• pp.514-518
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• 2007

It is necessary to modify the state-of-the-art of speed control theory because of the phase asymmetry in the Linear Induction Motor (LIM)and for the constant speed control of mover using single vector control inverter system, it is important that primary stack is located in appropriated intervals in the 3D conveyer system using LIM. The dynamic characteristic analysis method of the vector controlled LIM using coupled FEM and control algorithm taking into account the movement is proposed. The focus of this paper is the analysis relative to selecting primary stack intervals in order to constant speed control in the 3D conveyer system using LIM.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.3
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• pp.250-257
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• 1991

In the analysis of the electric machine by finite element method, the primary current has been selected as a driving source. But the voltage is constant and the primary current varies according to the load condition in the pracdtical system. Therefore, in this paper, magnetic flux distribution, primary current, input effective power, power factor, efficiency and propulsion force of S.L.I.M. were calculated by the finite element method cnsidering the voltage as a driving source. Because the driving characteristics could not be measured in the S.L.I.M., voltage-current curve, 3-phase current curve, and propulsion force were measured at the starting and they were compared with theoretical values.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.4
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• pp.1064-1071
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• 1994

There are three active radicals which become to the scale of flame diagnostics at the flame front. They are OH, CH and $C_2$ radical. For this, optical measurement system which could monitor simultaneously the luminous waves of three radicals, was constructed. These were analyzed statistically into the cross correlation, coherence and phase. Through such an statistical treatment, combustion characteristics was investigated at the primary zone of gas turbine combustor. The local equivalence ratio was predicted with the ratio of luminuous intensity between CH and $C_2$ radical. This result was matched up to the equivalence ratio calculated from gas composition within 5% error. In general, equivalence ratio was said to be 1.0 at flame front, but it could be increased up to about 1.2 depending on the degree of swirl intensity in case of changing properly the air amount of primary zone.

• Transactions on Electrical and Electronic Materials
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• v.16 no.1
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• pp.20-24
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• 2015

We studied the relationship between the surface smoothness of the internal Cu ribbon and the morphology of the Sn-Pb plating layer for solar cell modules. A bumpy surface was observed on the surface of the solar ribbon, which caused irregular reflection of light. Large, Pb-rich, primary ${\alpha}$-phases were found below the convex surface of the solar ribbon, passing from the surface of the internal Cu ribbon to the surface of the plating layer. The primary ${\alpha}$-phases heterogeneously nucleated on the convex surface of the Cu ribbon, and then largely grew to the convex surface of the plating layer. The restriction of the primary ${\alpha}$-phase's formation was enabled by enhancing the smoothness of the Cu ribbon's surface; it was also possible to increase the adhesive strength and decrease contact resistance. We confirmed that the solar ribbon's surface smoothness depends on the internal Cu ribbon's surface smoothness.

• Proceedings of the KIEE Conference
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• 1998.07b
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• pp.728-730
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• 1998

The control valve positioner is a high gain plain proportional controller which measures the valve stem position and compares it to its setpoint which is the primary controller output. The positioner in effect is the cascade slave of the primary controller. In order for a cascade slave to be effecttive, it must be fast enough compared to the speed of its set point change. This paper describes the positioner transfer function and its effect on the entire control loop characteristic based on the simulation results. The result showed that the control valve and positioner determined the gain and phase angle in the high frequency range, while the primary controller and process determined those of the low frequency range. We can also anticipate the combined characteristics in the whole frequency range when each element's frequency response is known.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.144-145
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• 2013

With the increasing public concerns on sustainability in construction industry around the world, a variety of standards for sustainable construction have been developed and implemented. However, most of the them focuses operation and maintenance phases and do not have been approached integrally in terms of all construction phases. Especially, considering the quantities of environmental loads occurred intensively at the construction phases, it should not be overlooked. Therefore, the purpose of this study is to deduct primary management works for reduction of the potential environmental loads at the construction phases. In order to assess them quantitatively, we conduct a survey from professionals who are in the relevant fields and analyze these data using Fuzzy-AHP.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.299-302
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• 2005

Semisolid A356 slurries were prepared by electromagnetic stirring casting and by inoculation of Al-5Ti-B master alloy. As stirring time and addition of Al-5Ti-B are different, the grain size of the primary phase is different. Through the experiment of rheocast in a Buhler horizontal die casting machine, it was found that the finer the equiaxed primary dendrites, the smoother the die filling and better cast quality. Small equiaxed primary dendrite also results in less liquid segregation on the surface.

• Journal of Integrative Natural Science
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• v.9 no.1
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• pp.28-34
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• 2016

A number of chiral selectors have been developed and applied for enantiomer separation of a variety of chiral compounds. Among these chiral selectors are chiral crown ethers, a class of synthetic host polyether molecules that bind protonated chiral primary amines with high selectivity and affinity. In this paper, two important chiral crown ethers as chiral selectors of bis-(1,1'-binaphthyl)-22-crown-6 and (18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) are focused. They have been widely used to resolve the enantiomers of chiral compounds containing a primary amino moiety using chiral stationary phases (CSPs) or chiral selectors by high-performance liquid chromatography (HPLC), capillary electrophoresis (CE) and so on in chirotechnology. Also, it was described that the commercially available covalent type HPLC CSPs derived from (+)- and (-)-18-C-6-TA have been developed and successfully applied for the resolution of various primary amino compounds including amino acids.

• Radiation Oncology Journal
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• v.37 no.3
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• pp.149-155
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• 2019

In metastatic non-small cell lung cancer (NSCLC), the role of radiotherapy (RT) has been limited to palliation to alleviate the symptoms. However, with the development of advanced RT techniques, recent advances in immuno-oncology therapy targeting programmed death 1 (PD-1) and programmed death ligand 1 (PD-L1) and targeted agents for epidermal growth factor receptor (EGFR) mutation or anaplastic lymphoma kinase (ALK) translocation allowed new roles of RT in these patients. Within this metastatic population, there is a subset of patients with a limited number of sites of metastatic disease, termed as oligometastasis that can achieve long-term survival from aggressive local management. There is no consensus on the definition of oligometastasis; however, most clinical trials define oligometastasis as having 3 to 5 metastatic lesions. Recent phase II randomized clinical trials have shown that ablative RT, including stereotactic ablative body radiotherapy (SABR) and hypofractionated RT, to primary and metastatic sites improved progression-free survival (PFS) and overall survival (OS) in patients with oligometastatic NSCLC. The PEMBRO-RT study, a randomized phase II study comparing SABR prior to pembrolizumab therapy and pembrolizumab therapy alone, revealed that the addition of SABR improved the overall response, PFS, and OS in patients with advanced NSCLC. The efficacy of RT in oligometastatic lung cancer has only been studied in phase II studies; therefore, large-scale phase III studies are needed to confirm the benefit of local ablative RT in patients with oligometastatic NSCLC. Local intensified RT to primary and metastatic lesions is expected to become an important treatment paradigm in the near future in patients with metastatic lung cancer.