• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.897-900
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• 2008

Some substances of cement could make underestimate concentration of hexavalent chromium(Cr(VI)) as they reduce Cr(VI) to Cr(III) in acidic condition during the determination of Cr(VI) content in cement. The reduction of Cr(VI) increased with elapsed time after acidification in this study. The reduction rate varied with various cements. From our result, we can conclude that simultaneous additions of acid and DPC were required for the accurate measurement of Cr(VI) in cement. The high recovery rate of 94.3 to 106.7% with the simultaneous acid-DPC addition method can also support our conclusion.

• The Transactions of the Korean Institute of Power Electronics
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• v.21 no.3
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• pp.238-248
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• 2016

In this study, an automatic command mode transition strategy of direct power control (DPC) is proposed for permanent magnet synchronous generators (PMSGs) medium-voltage (MV) offshore wind turbines (WTs). Benchmarking against the control methods are performed based on a three-level neutral-point-clamped (NPC) back-to-back type voltage source converter (VSC). The ramping rate criterion of complex power is utilized to select the switching vector in DPC for a three-level NPC converter. With a grid command and an MPPT mode transition strategy, the proposed control method automatically controls the generated output power to satisfy a grid requirement from the hierarchical wind farm controller. The automatic command mode transition strategy of DPC is confirmed through PLECS simulations based on Matlab. The simulation result of the automatic mode transition strategy shows that the proposed control method of VOC and DPC achieves a much shorter transient time of generated output power than the conventional control methods of MPPT and VOC under a step response. The proposed control method helps provide a good dynamic performance for PMSGs MV offshore WTs, thereby generating high quality output power.

• Journal of the Korean Chemical Society
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• v.19 no.6
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• pp.398-402
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• 1975

The light scattering studies of the aqueous solution of dodecyl pyridinium chloride (DPC) and tetradecyl pyridinium chloride (TPC) over the concentration range of 0~70 mM revealed that there exists a so-called 2nd critical micelle concentration (cmc) at about 43 mM and 8 mM respectively in addition to their 1st cmc at 17 mM and 3.5 mM. The 2nd cmc was greatly influenced by additives KCl, which lowered the 2nd cmc. The micelle molecular weight of DPC and TPC solutions at 1st cmc were 20800 and 15600 and the degree of ionization of their micelles at 1st cmc were 0.092 and 0.226 respectively.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.1
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• pp.40-51
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• 2009

A paired many-to-many k-disjoint path cover (paired k-DPC) of a graph G is a set of k disjoint paths joining k distinct source-sink pairs in which each vertex of G is covered by a path. In this paper, we investigate disjoint path covers in recursive circulants G($cd^m$,d) with $d{\geq}3$ and tori, and show that provided the number of faulty elements (vertices and/or edges) is f or less, every nonbipartite recursive circulant and torus of degree $\delta$ has a paired k-DPC for any f and $k{\geq}1$ with $f+2k{\leq}{\delta}-1$.

• Journal of Communications and Networks
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• v.13 no.3
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• pp.232-239
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• 2011

This paper investigates the user selection problem of successive zero-forcing precoded multiuser multiple-input multiple-output (MU-MIMO) downlink systems, in which the base station and mobile receivers are equipped with multiple antennas. Assuming full knowledge of the channel state information at the transmitter, dirty paper coding (DPC) is an optimal precoding strategy, but practical implementation is difficult because of its excessive complexity. As a suboptimal DPC solution, successive zero-forcing DPC (SZF-DPC) was recently proposed; it employs partial interference cancellation at the transmitter with dirty paper encoding. Because of a dimensionality constraint, the base station may select a subset of users to serve in order to maximize the total throughput. The exhaustive search algorithm is optimal; however, its computational complexity is prohibitive. In this paper, we develop two low-complexity user scheduling algorithms to maximize the sum rate capacity of MU-MIMO systems with SZF-DPC. Both algorithms add one user at a time. The first algorithm selects the user with the maximum product of the maximum column norm and maximum eigenvalue. The second algorithm selects the user with the maximum product of the minimum column norm and minimum eigenvalue. Simulation results demonstrate that the second algorithm achieves a performance similar to that of a previously proposed capacity-based selection algorithm at a high signal-to-noise (SNR), and the first algorithm achieves performance very similar to that of a capacity-based algorithm at a low SNR, but both do so with much lower complexity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.323-329
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• 1995

For the effective utilization of dark meat separated as by-product from skip-jack canning, the dark meat concentrate(DPC) was prepared by removal of extractable materials with ethanol from dried dark meat. Dark meat protein hydrolysate(DPH) was prepared by the hydrolysis of DPC with ${\alpha}-chymotrypsin$. ${\alpha}-Chymotrypsin$ hydrolysed DPC to the extend of 79% during 10hr. The solubility over a pH range 1~12 showed similar trend on the both of DPH and DPC. The highest solubility was 81% on the DPH and was 36% on the DPC at pH 3. The lowest solubility was 65% on the DPH and was 22% on the DPC at pH 7. The content of total free amino acid was higher in the DPC than in the DPH, but the content of total essential free amino acid was higher in the DPH. Especially, the contents of taurine in the DPC and DPH were much higher than those of other amino acids. The result of sensory evaluation on the fish sauce analogue showed good taste, color and odor at the supplemented level of 8g DPH per 100ml of raw solution of fish sauce analogue and didn't show signifcaint difference compared with market fish sauce(p<0.05). On the preparation of surimi gel, 2% substitution of DPH for the supplemented starch was the most appropriate level.

• Journal of the Korean Chemical Society
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• v.25 no.4
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• pp.275-282
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• 1981

A simple semiquantitative procedure was developed for the determination of sub-ppm level of chromium(VI) in aquatic samples by using an analytical micro-column packed with diphenylcarbazide(DPC) gel beads. DPC gel beads were prepared by swelling XAD-2 resin(115∼150 mesh in dry condition) in ethanol for 10min, packing into a glass column(1.5 mm bore, 65nm length) and adsorbing 1ml of ethanol solution of $2{\times}10^{-3}M$ DPC for 20min at room temperature. When 0.5ml of ethanol solution containing chromium(VI) was passed through the DPC gel column for 40min, the original white color of the reagent gel turned to red-violet from the up-stream of the column. As the length of colored band was proportional to the total amount of chromium(VI) in the sample solution passed through the column, the concentration of chromium(VI) could be determined from the calibration line which had been prepared by using the standard solution. Chromium(VI) ion as small as from 0.1 to 0.8 ppm could be determined with ${\pm}5{\sim}{\pm}15{\%}$ relative errors. Since other interfering cations were few, 100-fold excess of Fe(III), 50-fold excess of Cu(II) could be masked with EDTA. This method was successfully applied to the analysis of chromium(VI) in industrial effluents.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.3
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• pp.93-98
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• 2003

With the improvement of digital signal processors, digital pulse compressor(DPC) is widely used in radar systems. The DPC can be implemented by using FIR filter algorithm in time domain or FFT algorithm in frequency domain. This paper designs an expansible DPC using multiple DSPs. With ADSP-21060 of Analog Devices Inc., the computation time as a function of the number of received range cells and FIR filter tap is compared and analyzed in time domain using C-language and assembly language. therefore, when radar system parameters are determined, the number of DSP's required to implement DPC can be easily estimated.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.4
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• pp.16-41
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• 2020

Geospatial input setting to represent the reality of spatial distribution or quantitative property within model has become a major interest in earth system simulation. Many studies showed the variation of grid resolution could lead to drastic changes of spatial model results because of insufficient surface property estimations. Hence, in this paper, the authors proposed Monte Carlo Integration (MCI) to apply spatial probability (SP) in a spatial-sampling framework using a three-dimensional point cloud (3DPC) to keep the optimized spatial distribution and area/volume property of buildings in urban area. Three different decision rule based building identification results were compared : SP threshold, cell size, and 3DPC density. Results shows the identified building area property tend to increase according to the spatial sampling grid area enlargement. Hence, areal building property manipulation in the sampling frameworks by using decision rules is strongly recommended to increase reliability of geospatial modeling and analysis results. Proposed method will support the modeling needs to keep quantitative building properties in both finer and coarser grids.

• Physical Therapy Rehabilitation Science
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• v.10 no.4
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• pp.430-437
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• 2021

Objective: The purpose of this study was to investigate the effect of 3-dimensional posture correction(3DPC) exercise program incorporating PNF respiratory muscle strengthening(RMS) exercise on spinal alignment and trunk expansion in patients with idiopathic scoliosis and the difference in intervention effect by type of idiopathic scoliosis. Design: Comparative study using paired t-test and analysis of variance measures. Methods: The subjects of this study were 5 men and 24 women diagnosed with idiopathic scoliosis with a Cobb angle greater than 10 degrees and less than 45 degrees. A 3DPC exercise program incorporating PNF RMS exercise was conducted twice a week for 1 hour per session for 6 weeks, and Cobb angle, Angle of trunk rotation, and trunk expansion were measured before and after the intervention. Results: After the intervention, Cobb angle and trunk rotation angle showed a statistically significant decrease, and trunk expansion showed a statistically significant increase. In the effect difference by type, there was a statistically significant difference in the angle of trunk rotation of the thoracic in 3C and Single Lumbar. Conclusions: In conclusion, it is thought that a 3DPC exercise program incorporating PNF RMS exercise can be effectively used in clinical practice to improve spinal alignment and trunk expansion in patients with idiopathic scoliosis.