• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.2
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• pp.257-261
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• 2022

Additive manufacturing (AM, also known as 3D printing) applied to the construction industry is implemented and verified for various effects since advantages such as high design freedom, improving worker safety, and predictable construction period. However, due to the low maturity compared to the existing technology, studies are underway to solve new problems that occur in the overall of AM technology. In this paper, we confirm the effect of low construction surface flatness on the stacked features in the process of on-site AM construction. In particular, unstable AM features are determined through quantitative analysis by laser scanning, and a construction strategy is proposed for the surface flattening.

• Journal of Welding and Joining
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• v.31 no.3
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• pp.11-16
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• 2013

Through-silicon-via (TSV) is a major technology in microelectronics for three dimensional high density packaging. The 3-dimensional TSV technology is applied to CMOS sensors, MEMS, HB-LED modules, stacked memories, power and analog, SIP and so on which can be employed to car electronics. The copper electroplating is widely used in the TSV filling process. In this paper, the various Cu filling methods using the control of the plating process were described in detail including recent studies. Via filling behavior by each method was also introduced.

• Ocean and Polar Research
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• v.26 no.3
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• pp.385-400
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• 2004

The Lago Sofia Conglomerate encased in the 2km thick hemipelagic mudstones and thinbedded turbidites of the Cretaceous Cerro Toro Formation, southern Chile, is a deposit of a gigantic submarine channel developed along a foredeep trough. It is hundreds of meters thick kilometers wide, and extends for more than 120km from north to south, representing one of the largest ancient submarine channels in the world. The channel deposits consist of four major facies, including stratified conglomerates (Facies A), massive or graded conglomerates (Facies B), normally graded conglomerates with intraformational megaclasts (Facies C), and thick-bedded massive sandstones (Facies D). Conglomerates of Facies A and B show laterally inclined stratification, foreset stratification, and hollow-fill structures, reminiscent of terrestrial fluvial deposits and are suggestive of highly competent gravelly turbidity currents. Facies C conglomerates are interpreted as deposits of composite or multiphase debris flows associated with preceding hyperconcentrated flows. Facies D sandstones indicate rapidly dissipating, sand-rich turbidity currents. The Lago Sofia Conglomerate occurs as isolated channel-fill bodies in the northern part of the study area, generally less than 100m thick, composed mainly of Facies C conglomerates and intercalated between much thicker fine-grained deposits. Paleocurrent data indicate sediment transport to the east and southeast. They are interpreted to represent tributaries of a larger submarine channel system, which joined to form a trunk channel to the south. The conglomerate in the southern part is more than 300 m thick, composed of subequal proportions of Facies A, B, and C conglomerates, and overlain by hundreds of m-thick turbidite sandstones (Facies D) with scarce intervening fine-grained deposits. It is interpreted as vertically stacked and interconnected channel bodies formed by a trunk channel confined along the axis of the foredeep trough. The channel bodies in the southern part are classified into 5 architectural elements on the basis of large-scale bed geometry and sedimentary facies: (1) stacked sheets, indicative of bedload deposition by turbidity currents and typical of broad gravel bars in terrestrial gravelly braided rivers, (2) laterally-inclined strata, suggestive of lateral accretion with respect to paleocurrent direction and related to spiral flows in curved channel segments around bars, (3) foreset strata, interpreted as the deposits of targe gravel dunes that have migrated downstream under quasi-steady turbidity currents, (4) hollow fills, which are filling thalwegs, minor channels, and local scours, and (5) mass-flow deposits of Facies C. The stacked sheets, laterally inclined strata, and hollow fills are laterally transitional to one another, reflecting juxtaposed geomorphic units of deep-sea channel systems. It is noticeable that the channel bodies in the southern part are of feet stacked toward the east, indicating eastward migration of the channel thalwegs. The laterally inclined strata also dip dominantly to the east. These features suggest that the trunk channel of the Lago Sofia submarine channel system gradually migrated eastward. The eastward channel migration is Interpreted to be due to tectonic forcing imposed by the subduction of an oceanic plate beneath the Andean Cordillera just to the west of the Lago Sofia submarine channel.

• Korean Journal of Materials Research
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• v.13 no.12
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• pp.825-830
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• 2003

Structural changes during oxidation of anisotopic mesophase carbon fiber(AMCFs) have been observed with TEM and XRD. It was shown that the AMCFs are three dimensionally stacked structure of turbostratic layers, and are non-homogeneous structure which consist of the highly ordered areas and the random areas. The $d_{ 002}$, Lc, and La of AMCFs which were measured by XRD were 3.44, 146, and $135\AA$, respectively. It was observed that the oxidation initiated at the random areas, because the $d_{002}$ / decreased to the value of 3.41 $\AA$ during initial oxidation stage. It was also observed that the La of the oxidized AMCFs increased up to 182 $\AA$ during the whole oxidation process, and the $d_{002}$ of that increases up to 9.44 $\AA$ when the burn-off is over the degree of 20%. Therefore, it was suggested that the micro-crystalline grew up by heat treatment effects during the fibers were oxidized, In addition, it was shown that there was difference in the measured value of La by XRD and TEM, in case of 39% oxidized fibers for example, the measured La was $ 165\AA$ by XRD and in the range of 180∼220 $\AA$ by TEM.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1929_1930
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• 2009

Fully embedded tunable bandpass filter (BPF) with inductive coupling circuits is newly designed and demonstrated for UHF TV tuner ranged from 500MHz to 900MHz receivers. Conventional RF tuning circuit with an electromagnetic coupled tunable filter has several problems such as large size, high volume, and high cost, since the electromagnetic coupled filter is comprised of several passive components and air core inductors to be assembled and controlled manually. To address these obstacles, compact tunable filter with inductive coupling circuit was embedded into low cost organic package substrate. The embedded filter was optimally designed to have high performance by using high Q spiral stacked inductors, high dielectric $BaTiO_3$ composite MIM capacitors, varactor diodes. It exhibited low insertion loss of approximately -2dB, high return loss of below -10dB, and large tuning range of 56.3%. It has an extremely compact size of $3.4{\times}4.4{\times}0.5mm^3$.

• Journal of Animal Science and Technology
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• v.45 no.1
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• pp.79-86
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• 2003

To determine nutritive value and suitability of deep-stacked broiler litter for deer, the influence of supplementary levels of broiler litter on digestibility, dry matter intake, and nitrogen balance was investigated in male spotted deer (Cervus nippon) fed a commercial mixed(complete) ration. The deep-stacked and ground broiler litter was supplemented at the level of 0%(Control), 15%(T1) and 30%(T2) on the basis of fresh matter to the mixed ration. All treatments had similar palatability at about 3% body weight of dry matter intake. Dry matter digestibility was highest in Control and lowest in T2(P<0.05). Digestibility of crude protein was lowest(P<0.05) in T2. Dry matter and digestible dry matter intake was similar in all treatments. Daily body weight gain was not affected by treatments. Feeding 15 or 30% of broiler litter to male deer resulted in similar nitrogen intake, fecal nitrogen excretion and daily nitrogen retention(g/d), compared with feeding Control. These results suggest that up to 30% of broiler litter may be fed to male deer without deleterious effects on deer performance.

• Science of Emotion and Sensibility
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• v.16 no.1
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• pp.85-94
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• 2013

Recently, researches of piezoelectric energy harvesting were tried and in this study, a piezoelectric energy harvesting clothes was developed. First, piezoelectric energy harvesting zone on the extremities were drawn by 3D motion capturing and as a result, the hip, the elbow, and the knee were determined. A new structure of piezoelectric harvester was developed for appling to clothes. Because it needed to be flexible and sensitive for human body, the 2 layer stacked structure was proposed. A prototype of seamless garment was designed for a harvesting clothes because it needed to be body-tight and not to restrict the movement. High peak-to-peak voltages were acquired from the energy harvesting clothes.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.630-632
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• 2003

In this paper, we present the fabrication and performance of FBAR filters with ladder and stacked crystal filter (SCF) types. The structure of the unit resonator in our work is the solidly mounted resonator (SMR) with W/SiO$_2$ multi-layer reflectors, the return loss of of which show -24dB at resonant frequency of -2.0GHz. The $K^2$eff, Q$_{s}$, and Q$_{p}$, indicating the performance of resonator were 3.24%, 6,363 and 6,749 and were calculated for the resonator with the resonance area of 21200${\mu}{\textrm}{m}$$^2$. Based on this unit resonator, FBAR filters with ladder and SCF types were fabricated and compared. The sizes of filters were 800$\times$2000(${\mu}{\textrm}{m}$$^2$) for the ladder type and 600$\times$500(${\mu}{\textrm}{m}$$^2$) for the SCF type.e..

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.587-596
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• 2014

A new ${\pi}$-stacked donor-acceptor (D-A) system, [Ru(1-([2,2'-bipyridine]-6-yl-methyl)-3-(2-cyclohexa-2',5'-diene-1,4-dionyl)-1H-imidazole)(2,2':6',2"-terpyridine)]$[PF_6]_2$ (ImQ_T), has been synthesized and characterized. Similar to its precedent, [Ru(6-(2-cyclohexa-2',5'-diene-1,4-dione)-2,2':6',2"-terpyridine)(2,2':6',2"-terpyridine)]$[PF_6]_2$ (TQ_T), this system has a cofacial alignment of terpyridine (tpy) ligand and quinonyl (Q) group, which facilitates an electron transfer through ${\pi}$-stacked manifold. Despite the presence of lowest-energy charge transfer transition from the Ru-based-HOMO-to-Q-based-LUMO (MQCT) predicted by theoretical calculations by using time-dependent density functional theory (TD-DFT), the experimental steady-state absorption spectrum does not exhibit such a band. The selective excitation to the Ru-based occupied orbitals-to-tpy-based virtual orbital MLCT state was thus possible, from which charge separation (CS) reaction occurred. The photo-induced CS and thermal charge recombination (CR) reactions were probed by using ultrafast visible-pump/mid-IR-probe (TrIR) spectroscopic method. Analysis of decay kinetics of Q and $Q^-$ state CO stretching modes as well as aromatic C=C stretching mode of tpy ligand gave time constants of <1 ps for CS, 1-3 ps for CR, and 10-20 ps for vibrational cooling processes. The electron transfer pathway was revealed to be Ru-tpy-Q rather than Ru-bpy-imidazol-Q.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2005.11a
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• pp.221-224
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• 2005

In this paper, We have designed, fabricated and measured a stacked planar antenna for Ultra-Wideband communication. Radiation parts of the antenna have exponential curve and fed by strip feeding network. We have used the HFSS of Ansoft to simulate the antenna. It was designed to work on a substrate Teflon of thickness 1.575mm and relative permittivity 3.2. The proposed antenna covered the entire UWB band( 3.1GHz $\sim$ 10.6GHz ) for S11$\leq$l0dB. Also the proposed antenna show a good characteristics, linear phase, omni -directional pattern lot UWB applications. Besides the measured results have a reasonable agreement with the simulated results.