• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.1
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• pp.51-58
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• 2006

The objective of this research work is to investigate into heat transfer characteristics of the laser cutting of CSP 1N sheet using high power CW Nd:YAG laser. In order to investigate the heat transfer characteristics, three dimensional quasi stationary and steady-state heat transfer analysis has been carried out. The laser heat source is assumed as a volumetric heat source with a gaussian heat distribution in a plane. Through the comparison of the results of analyses with those of experiments, the proper finite element model has been obtained. In addition, characteristics of the three-dimensional heat transfer and temperature distribution have been estimated by the finite element model. Finally, the minimum temperature at the center for cutting of the material has been estimated.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.10
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• pp.510-514
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• 2004

In this paper, we analytically examine the voltage transfer function dependent on input conditions for an N-Input NAND Gate. The logic threshold voltage, defined as a voltage at which the input and the output voltage become equal, changes as the input condition changes for a static NAND Gate. The logic threshold voltage has the highest value when all the N-inputs undergo transitions and it has the lowest value when only the last input connected to the last NMOS to ground, makes a transition. This logic threshold voltage difference increases as the number of inputs increases. Therefore, in order to provide a near symmetric voltage transfer function, a multistage N-Input Gate consisting of 2-Input Logic Gates is desirable over a conventional N-Input Gate.

• ETRI Journal
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• v.27 no.5
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• pp.647-650
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• 2005

A new configuration to realize the most general n-th order voltage transfer function is proposed. It employs only one operational transresistance amplifier (OTRA) as the active element. In the synthesis of the transfer function, the RC:-RC decomposition technique is used. To the best of author's knowledge, this is the first topology to be used in the realization of n-th order transfer function employing single OTRA.

• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.22-25
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• 2005

In this research, a wafar-level transfer method of cantilever array on a conventional CMOS circuit has been developed for high density probe-based data storage. The transferred cantilevers were silicon nitride ($Si_3N_4$) cantilevers integrated with poly silicon heaters and piezoelectric sensors, called thermo-piezoelectric $Si_3N_4$ cantilevers. In this process, we did not use a SOI wafer but a conventional p-type wafer for the fabrication of the thermo-piezoelectric $Si_3N_4$ cantilever arrays. Furthermore, we have developed a very simple transfer process, requiring only one step of cantilever transfer process for the integration of the CMOS wafer and cantilevers. Using this process, we have fabricated a single thermo-piezoelectric $Si_3N_4$ cantilever, and recorded 65nm data bits on a PMMA film and confirmed a charge signal at 5nm of cantilever deflection. And we have successfully applied this method to transfer 34 by 34 thermo-piezoelectric $Si_3N_4$ cantilever arrays on a CMOS wafer. We obtained reading signals from one of the cantilevers.

• International Journal of Air-Conditioning and Refrigeration
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• v.6
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• pp.113-123
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• 1998

The present study is to investigate the effect of experimental parameters on the heat transfer characteristics of a spherical capsule storage system using paraffins. N-Tetradecane and mixture of n-Tetradecane 40% and n-Hexadecane 60% were used as paraffins. Water with inorganic material was also tested for the comparison. The experimental parameters were varied for the Reynolds number from 8 to 16 and for the inlet temperature from -7 to 2$^{\circ}C$. Measured local temperatures of spherical capsules in the storage tank were utilized to calculate charging and discharging times, dimensionless thermal storage amount, and the average heat transfer coefficients in the tank. Local charging and discharging times in the storage tank were significantly different. The effect of inlet temperature on charging time was larger than that on discharging time, but the effect of Reynolds number on charging time was smaller than that on discharging time. Charging time of paraffins was faster by 11~72% than that of water with inorganic material, but little difference of discharging time was found among them. The effect of Reynolds number on the dimensionless thermal storage was less during charging process and more during discharging process than the effect of inlet temperature. The effect of the inlet temperature and the Reynolds number on the average heat transfer coefficient of the storage tank was stronger during discharging process than during charging process. The average heat transfer coefficients of the spherical capsule system using paraffins were larger by 40% than those using water.

• Clean Technology
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• v.22 no.1
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• pp.45-52
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• 2016

This study reports on the modeling and simulation of heat transfer in packaging boxes used for vaccine shipping. Both water and n-tetradecane are used as primary insulation materials inside a multi-slab system. The one-dimensional model, which is a spherical model using a radius equivalent to the rectangular geometry of container, is applied in this study. N-tetradecane with low thermal diffusivity and proper phase transition temperature exhibits higher heat transfer resistance during both heating and cooling processes compared to water. Thus, n-tetradecane is a better candidate as an insulating material for packaging containers for vaccine shipping. Furthermore, the developed method can also become a rapid and economic tool for screening appropriate phase change materials used as insulation materials with suitable properties in logistics applications.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.2
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• pp.15-23
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• 2013

In this paper, we propose a session management and control architecture for N-Screen services, which enable users to change devices and transfer contents among user's devices during service by session transfer and split. In N-Screen services, users may have multiple devices with different attribute such as screen resolution, CPU capability and access network interfaces. Also, since users may change devices during service, or one user may use multiple stream, N-Screen services need to enable the user to share and transfer contents across N-Screen devices. We introduce the management and control servers to provide session split over user multiple devices and session continuity while changing device. Furthermore, the proposed architecture provides the device capabilities aware session continuity. In addition, the proposed scheme minimizes the session transfer delay and content server processing load. We present results that show the effectiveness and usefulness of proposed architecture.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.381-389
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• 2013

In order to study the effect of organic fertilizer on dry matter (DM) yield, nitrogen fixation and transfer from pea to barley, an experiment was carried out from May to June in 2008 in Incheon. A completely randomized block design with three replications was used for the experiment and one reference plot assigned each treatment for nitrogen fixation evaluation. Seeding mixture was 40kg barley and 80kg pea per ha. N rate of 40, 80 and 120kg/ha as organic fertilizer was applied at seeding. The equivalent of 1kg per ha as $(15NH_4)_2SO_4$ Solution at 99.8 atom N was applied to the plots ($30{\times}20cm$) at mid April. Forage was harvested from each plot in ripening stage at ground level and separated into barley and pea. Nitrogen fixation was 32.4%, 23.4% and 0% at three different organic N levels. Transfer rate were from 47.6% to 21.8% in difference method and 24.6% and 21.4% on $^{15}N$ dilution method. N Transfer amount were from 92.8kg/ha to 41.9kg/ha on difference method and 47.3kg in the 40kg N plots and 49.7kg in the 80kg N plots on $^{15}N$ dilution method but there was no N transfer in 120kg N organic fertilizer plots. Benefit from increased organic fertilizer was not clear in terms of nitrogen fixation and transfer from pea to barley in barley and pea mixtures.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.752-755
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• 2008

Mesoporous SBA-15 silica-supported TsCHDA and TsDPEN ligands have been prepared by reaction of SBA-15 silica with (1R,2R)-N-(trimethoxysilylpropyl-N-sulfonyl)-1,2-cyclohaxanediamine or (1R,2R)-N-(trimethoxysilylpropyl-N-sulfonyl)-1,2-diphenylethylenediamine-1,2-diphenylethylenediamine, respectively. The Ru complexes exhibited excellent catalytic activity and satisfactory enantioselectivity in the asymmetric hydrogen transfer of ketones under microwave conditions. The heterogeneous Ru catalyst was reusable as well as air-stable to allow easy use. Microwave-assisted efficient procedure has been developed for asymmetric hydrogen transfer.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.161-164
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• 2011

Nitrogen fixation by legumes can be valuable sources for organic farming. This study was to investigate the effect of different legume mixtures on nitrogen fixation and transfer to grasses on spring paddy field. Three different mixtures were used (rye+hairy vetch, Italian ryegrass+crimson clover, oat+pea) in a randomized complete block design with three replications and sowed in pots with different sowing rate (5:5 rye:hairy vetch,7:3=Italian:crimson, 6:4=oat:pea) on early March. $(^{15}NH_4)SO_4$ solution at. 99.8 atom%$^{15}N$ was applied to the each pot at the rate of 2kg N $ha^{-1}$ on $16^{th}$ April. Forage were harvested at ground level in heading stage and separated into legume and grass. Total N content and $^{15}N$ value were determined using a continuous flow stable isotope ratio mass spectrometry. DM yield of rye+vetch, Italian+crimson and oat+pea were 6,607, 3,213 and 4,312kg/ha, respectively. Proportion of N from fixation was 0.73(rye+vetch), 0.42(Italian+crimson) and 0.93(oat+pea). The percentages of N transfer from legume to grass were from 61% to 24% in different method by treatments and -35% to 21% in isotope dilution method.