• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.11
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• pp.226-233
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• 2013

In this study, In Laver's automatic drying device, laver thickness measurement and control devices that are associated with. Disconnect the water and steam, after put a certain amount of the mixture(water and laver) in the mold. In process, Laver of the size and thickness (weight) to determine, constant light source to detect and image LED Lamp occur Vision Sensor (Camera) prepare, then the values of these state of the image is transmitted in real time embedded computers. Built-in measurement and control with the purpose of the application of each of the channels separately provided measurements are displayed on a monitor, And servo signals sent to each of the channels and it become so set function should be. In this paper, the laver drying device, prior to the laver thickness measurement and control devices that rely on the experience of existing workers directly laver manually adjust the thickness of the lever, but the lever by each channel relative to the actuator by installing was to improve the quality. In addition, The effect of productivity gains and labor savings are.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.5C
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• pp.532-538
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• 2003

In this paper we have investigated a novel approach applying low-density parity-check coding to a COFDM-CDMA system, which operates in a multi-path fading mobile channel. Developed as a linear-block channel coder, the LDPC code is known for a superior signal reception capability in AWGN and/or flat fading channels with respect to increased encoding rates, however, its performance degrades when the communication channel becomes multi-path fading. For a typical multi-path fading mobile channel with a SNR of 16㏈ or lower. in order to obtain a BER lower than 1 out of 10000, the LDPC code with encoding rates below 1:3 requires not only the inherent parity check information but also the piloting information for refreshing front-end equalizer taps of COFDM-CDMA, periodically. For instance, while the 1:3-rate LDPC coded transmission symbol is consisted of data bits and parity-check bits in 1 to 3 proportion, on the other hand, in the proposed method the same rate LDPC transmission symbol contains data bits, parity check bits, and pilot bits in 1 to 2 to 1 proportion, respectively. The included pilot bits are effective not only for channel estimation and channel equalization but for symbol decoding by assisting the parity-check bits, hence, improving SNR vs BER performance over the conventional 1:3-rate LDPC code. The proposed system performance has been verified using computer simulations in multi-path, Rayleigh fading channels, and the results show us that the proposed method out-performs the general LDPC channel coding methods in terms of SNR vs BER measurements.

• Food Science and Preservation
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• v.23 no.5
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• pp.631-637
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• 2016

Quality characteristics of Yanggaeng prepared with water extract (CRE) and powder (CRP) of roasted coffee ground (CR) were investigated. Total polyphenol content and DPPH raidcal scavenging ability of water extract of CRE were 13.52 g/mL and 78.75%, respectively. The pH ranges of Yanggaeng prepared with CRE (CREY) and CRP (CRPY) were 7.10~7.29 and 6.95~7.15, respectively. The DPPH radical scavenging activities of CREY containing 0.1~1.0% CRE showed 8.77~43.10% and CRPY containing 0.1~1.0% CRP showed 5.28~14.92%. The total polyphenol contents and DPPH radical scavenging activity of CREY and CRPY increased significantly with increasing CRE and CRP concentrations (p<0.05). Sensory evaluation which includes taste, flavor, texture, and overall acceptability of CREY and CRPY were higher than that of control. The overall acceptability showed the highest levels in Yanggaeng containing 0.5% CRE and containing 0.3% CRP. These results indicate the potential use of roasted coffee ground residue as a valuable resource for development of side menu in coffee restaurants.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.12
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• pp.127-134
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• 2005

Lost packet robustness is an most important quality measure for voice over IP networks(VoIP). Recovery of the lost packet from the received information is crucial to realize this robustness. So, this paper proposes the lost packet recovery method from the received information for real-time communication for CELP coder. The proposed BS-PLC (Both Side Packet Loss Concealment) based WSOLA(Waveform Shift OverLab Add) allow the lost packet to be recovered from both the 'previous' and 'next' good packet as the LP parameter and the excitation signal are respectively recovered. The burst of packet loss is modeled by Gilbert model. The proposed scheme is applied to G.729 most used in VoIP and is evaluated through the SNR(signal to noise) and the MOS(Mean Opinion Score) test. As a simulation result, The proposed scheme provide 0.3 higher in Mean Opinion Score and 2 dB higher in terms of SNR than an error concealment procedure in the decoder of G.729 at $20\%$ average packet loss rate.

• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.140-147
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• 1988

The pysicochemical and bacteriological properties of yogurts made by single or mixed cultures of L. bulgaricus FRI025 and S. thermophilus CHI were investigated. L. bulgaricus FRI025 which was isolated from raw milk was selected as starter culture among 22 strains of lactic culture by measuring viscosity, flavor, growth and acid production ability. The acid production and number of viable cell were increased by using L. bulgaricus FRI025 and S. thermophilus CHI together in ratio of apporximately 1:1. The pH, titratable acidity, viable cell number and viscosity of yogurt were 4.08, 1.14%, $2.5{\times}10^{10}/ml$ and 2100 cp after 9 hours incubation at $40^{\circ}C$, respectively. The pH and viable cell number were decreased on the other hand titratable acidity and viscosity were increased after 7 days of storage at $4^{\circ}C$. The changes of quality did not show significantly after storage. The selected starter was much higher than commercial yogurt starter in the acid production and growth of starter. The yogurt nanufactured with selected starter was better than with commercial yogurt in sensory evalution such as taste, texture, flavor and overall acceptability.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.4
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• pp.211-217
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• 2004

The instrument used in this study consists of a lkg capacity loadcell and a Imm tipping bucket rain gauge. There are two signals: one is the weight of the water in the tipping bucket and the other is the pulse from the reversing mechanism of the tipping bucket. The loadcell measures the weight of water with a 0.0lmm resolution up to 1mm rainfall and the bucket reverses beyond 1mm. From this point, a pulse signal generates and the loadcell starts measuring the weight again. A field test was carried out with the range of rainfall intensity from 42mm/h to 250mm/h. The result shows an error range from -2.2% to + 2.6% in 12 measurement cases with a rainfall of l00mm or more. This result satisfies the WMO recommendation for rainfall intensity instrumentation which allows a 5% range. In a field experiment during 17 to 19 August, 2004, more than 100mm/h rainfall intensity was observed by this instrument, confirming that our instrument has a sufficient capacity of rainfall intensity measurement under extreme conditions like Jangma (Bai-u season). Compared with existing commercial models which employ a water drop measurement method, our method can give a practical solution for diagnostic check of remote rain gauges using two independent signals.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.173-173
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• 2013

최근에 고효율의 형광체를 개발하고자 무기물 모체에 주입된 희토류 이온의 발광에 대한 연구가 급부상하고 있다. 형광체는 고휘도, 넓은 시청 각도와 저 비용으로 인하여 대형 평판 디스플레이 분야로 그 응용성을 확장하는 플라즈마 디스플레이 패널 제작에 있어서 매우 중요한 물질이다. 현재 적색 형광체로 널리 사용되고 있는 발광 물질은 YBO3:Eu3+ 혹은 (Y,Gd)BO3:Eu3+ 형광체이지만, Eu3+ 이온이 중심대칭의 자리에 위치하기 때문에, Eu3+ 이온의 5D07F1 전이에 의한 주황색의 발광 세기가 5D07F2 전이에 의한 적색의 세기보다 강하여 고품질의 색상을 구현하는데 상당한 어려움이 있다. 이러한 문제점을 해결하기 위하여 새로운 모체 격자를 갖는 적색, 녹색, 청색 형광체 개발에 많은 노력이 집중되고 있다. 본 연구에서는 형광체 합성시 중요한 변수의 하나인 소결 온도가 새로운 다양한 색을 방출하는 형광체 분말 CaSiO4:RE3+ (RE=Eu, Sm, Tb, Dy, Ce)의 특성에 미치는 영향을 조사하였다. CaSiO4:RE3+ (RE=Eu, Sm, Tb, Dy, Ce) 형광체 분말 시료는 초기 물질 CaO (99.99%), SiO2 (99.99%), Eu2O3 (99.99%), Sm2O3 (99.9%), Tb4O7 (99.9%), Dy2O3 (99.9%), CeO2 (99.9%)을 화학적량으로 준비하였다. 볼밀, 건조 작업을 한 후에, 시료를 막자사발에 넣고 분쇄하여 3시간의 하소 공정과 5시간의 소결 공정을 수행하였다. 이때 소결 온도를 변수로 선택하여 각각 $800^{\circ}C$, $900^{\circ}C$, $1,000^{\circ}C$, $1,100^{\circ}C$에서 소결 작업을 수행하여 합성 분말의 구조, 표면, 광학적 특성을 측정하여 소결 온도가 미치는 영향을 조사하였다. Eu3+가 도핑된 CaSiO4 형광체 분말의 경우에, 발광 스펙트럼은 597, 618, 655, 707 nm에서 관측되었으며, 소결 온도가 $800^{\circ}C$에서 $1,100^{\circ}C$로 증가함에 따라 모든 발광 스펙트럼의 세기는 순차적으로 증가함을 나타내었다. Tb3+가 도핑된 CaSiO4 형광체 분말의 경우에 관측된 발광 스펙트럼은 주 피크인 549 nm를 중심으로 하여 세기가 상대적으로 작은 493, 592, 626 nm의 피크들이 관측되었으며, 소결 온도가 증가함에 따라 전반적으로 발광 세기들이 증가하는 경향을 나타내었다. Sm3+가 도핑된 CaSiO4 형광체의 경우에, 발광 스펙트럼은 전형적인 Sm3+이온에 의한 전이 신호들이 605, 570, 653 nm에서 나타났다. 발광 스펙트럼의 세기는 소결 온도에 비례하여 증가하였다. Ce3+가 도핑된 경우에 발광 스펙트럼은 소결 온도에 관계없이 401 nm에서 관측되었으며, 소결 온도에 따라 발광 세기의 변화가 나타났다. 이 실험 결과로 부터, 합성시 적절한 소결 온도의 선택이 고발광 효율의 형광체를 제작하는데 있어서 매우 중요한 요소가 됨을 확인할 수 있었다.

• Korean Journal of Remote Sensing
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• v.15 no.2
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• pp.131-146
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• 1999

The satellite visible data have been successfully applied to study the ocean color. Another ocean color sensor, the Ocean Scanning Multi-spectral Imager (OSMI) on the Korea Multi-Purpose Satellite (KOMPSAT) will be launched in 1999. In order to understand the characteristics of future OSMI images, we have first discussed the simulation models and procedures in detail, and produced typical patterns of radiances at visible bands by using radiative transfer models. The various simulated images of full satellite passes and Korean local areas for different seasons, water types, and the satellite crossing equator time (CET) are presented to illustrate the distribution of each component of radiance (i.e., aerosol scattering, Rayleigh scattering, sun glitter, water-leaving radiance, and total radiance). A method to evaluate the image quality and availability is then developed by using the characteristics of image defined as the Complex Signal Noise Ratio (CSNR). Meanwhile, a series of CSNR images are generated from the simulated radiance components for different cases, which can be used to evaluate the quality and availability of OSMI images before the KOMPSAT will be placed in orbit. Finally, the quality and availability of OSMI images are quantitatively analyzed by the simulated CSNR image. It is hoped that the results would be useful to all scientists who are in charge of OSMI mission and to those who plan to use the data from OSMI.

• Food Science and Preservation
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• v.15 no.5
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• pp.669-674
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• 2008

Mul-kimchi is more watery than traditional kimchi and is prepared using large amounts of salted water, Chinese cabbage, radishes, and carrots. The quality characteristics of Mul-kimchi prepared with Chaenomelis Fructus water extract (1, 3, or 5%, w/v) (CF Mul-kimchi) or water (control) were investigated during fermentation for 21 days at $10^{\circ}C$. The initial pH values were 6.53 (control), 4.14 (1% CF Mul-kimchi), 3.61 (3% CF Mul-kimchi), and 3.54 (5% CF Mul-kimchi). The pH did not change significantly in CF Mul-kimchi but gradually decreased in the control during fermentation. Changes in titratable acidity were reflected in pH movements. Viable lactic acid bacteria in CF Mul-kimchi were at lower levels than in the control. Viable bacterial levels in Mul-kimchi decreased with increasing concentration of CF water extract. Textural features, such as hardness, cohesiveness, chewiness, and springiness, were higher in CF Mul-kimchi than in control. Anti-oxidative activity, measured by DPPH radical scavenging and nitrite scavenging, of CF Mul-kimchi, were higher than in control, and the activities rose with increasing levels of CF water extract. The sensory qualities of 1% CF Mul-kimchi showed the highest values in taste and overall acceptability among the Mul-kimchi preparations tested.

• Food Science and Preservation
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• v.17 no.5
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• pp.637-643
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• 2010

We investigated the characteristics of breads containing Schizandra chinensis Baillon (SCB) added as whole powder, as a powder prepared from juice, and as a concentrate prepared from a 95% (v/v) ethanolic fruit extract, added to wheat flour at 0.5% (w/w). Addition of any form of SCB lowered the pH and increased the titratable acidity in both doughs and breads compared with control values, and the whole and juice powders were more effective in this respect than was the concentrated ethanolic extract. Dough volume during fermentation was increased by addition of whole powder and concentrated ethanolic extract, but no baking loss was evident upon addition of any form of SCB. Regarding the bread surface, the lightness (L) value was increased by addition of juice powder and concentrated ethanolic extract, but neither the redness(a) and nor the yellowness (b) values showed such increases. Internal color measurements showed increased '-a-' value upon addition of any form of SCB, and increased '-b-' value when concentrated ethanolic extract was used, however, there were no significant changes in L value. Sensory evaluation of taste, flavor, color, and overall acceptability showed that bread prepared using whole powder was more acceptable than were the other forms.