• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.11 no.3
• /
• pp.115-120
• /
• 2011

This paper is concerned with the performance comparison of CR-CMA (Coordinate Reduction-CMA) and CM-CMA (Constellation Matching-Constant Modulus Algorithm) that is used for improving the convergence characteristic and residual intersymbol interference which are used as the performance index for an adaptive equalizer. The equalizer is used to reduce the distortion caused by the intersymbol interference on the wireless and the wired band-limited channel, and the blind method which does not need for extra bandwidth by the training sequence of digital code are researched. Recently, by using the merit of simple operation in the CMA, the performance improvement is obtained by the modifying the cost function of it. In this paper, the new algorithm, CR-CMA and CM-CMA, the performance analysis are performed and compared by computer simulation. The CR-CMA has a superior equalization characteristics in the recovered constellation, convergence speed and residual intersymbol interference than the CM-CMA by computer simulation.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.19 no.5
• /
• pp.47-54
• /
• 2019

In this paper, we consider a constant modulus (CM) based blind adaptive receiver design for downlink multi-carrier code-division multiple access (MC-CDMA) systems employing simple space-time block coding (STBC). In the paper, filter weight vectors used for the detection of the transmitted symbols are partitioned into its subvectors and then, special relations among the optimal subvectors minimizing the CM metric are derived. Using the special relations, we present a modified CM metric and propose a new blind adaptive stochastic-gradient CM algorithm (SG-CMA) by minimizing the modified CM metric. The proposed blind adaptive SG-CMA has faster convergence rate than the conventional SG-CMA because the filter weight vectors of the proposed scheme are updated in the region of satisfying the derived special relations. Computer simulation results are given to verify the superiority of the proposed SG-CMA.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.4C
• /
• pp.413-423
• /
• 2003

The CMA algorithmis most widely investigated blind algorithm and the most widely used one in practice. But, since nonlinear CM cost function have not closed form solution about the optimum weight. There have been difficultiesto analyze the CMA equalizer's theoretical performance. Recently, Zeng presents the notable theoretical resultabout the MSE of CM-minimizing estimators for the FIR linear channel in the presence of AWGN. Through this method, It wouldbe possible to campare the theoretical performance between CMA and Wiener equalizer in terms of MSE. In this paper, based on Zeng's method, we first calculate the theoretical MSE bound of CMA equalizer in partial response channel which is widely used in HDD, digital VCR such as high-density digital recording.playback systems. We confirmedthis result withthe computer simulation. Except this, we also performedthe theoretical and simulation analysis about the modified CMA equalizer, which was proposed to improve the performance of CMA equalizer in partial response channel. Finally, we compare and evaluate the performance analysis results between CMA and Modified CMA equalizer.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.10 no.1
• /
• pp.121-127
• /
• 2010

This paper relates with the improved CMA blind adaptive equalization algorithm which uses the constellation matching method that improve the inverse modelling efficiency of a communication channel compared to the present CMA blind adaptive equalizer. The amplitude distortion can be compensated in the present CMA blind adaptive equalizer which is used for the reduction of intersymbol interference by distortion that generate such as a band limited wireless mobile channel, but in the improved adaptive alogorithm operates with the minimize the amplitude phase distortion in the output of equalizer by applying the cost function that is composition of additional signal constellation matching error terms. In order to evaluation of the inverse modeling efficiency of improved algorithm, the residual intersymbol interference and recovered signal constellation were compared by computer simulation. As a result of comparion of computer simulation, the improved algorithm has a good stability in the residual intersymbol interference in the steady state, but it has a slow convergence rate in the adaptation state in initial state.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.5C
• /
• pp.601-610
• /
• 2004

In this paper, the performance of an adaptive array antenna using Constant Modulus Algorithm (CMA) based on the signal structure for the IMT-2000 3GPP specification reverse link of an asynchronous direct sequence code division multiple access (DS-CDMA) system are evaluated. In addition, the performance is compared with the array antenna using Least Mean Square (LMS) based on the training signal. The simulation parameters such as the number of multipath, mu10pa1h intensity profiles between path, spreading gain and multiuser etc., are considered in the Monte Carlo simulation. Simulation results demonstrate an adaptive array antenna using CMA may give more capacity gain than the amy antenna using LMS in the case of multipath fading channel.

• Research in Plant Disease
• /
• v.7 no.1
• /
• pp.16-19
• /
• 2001

The cultural caracteristics of Monosporascus cannonballus causing root rot of Cucurbitaceae plants were examined in vitro, and population density of the fungal ascospores were measured and compared aoming diferent host species and soil depths. Potato-dextrose agar(PDA) was the most appropriate medium for the mycelial growth and perithecial formation among the 5 media tested. Corn-meal agar(CMA), oat-meal agar (OMA) and V-8 juice agar were moderate media for the mycelial growth and perithecial formation, whereas water agar(WA) was poor medium. Perithecia were not formed on WA. Optimum temperature for the formation of perithecia was about 25 to 30$^{\circ}C$. distribution of ascospores in the infested fields was variable amount the curcubitaceae plants and within the same plant species, ranging from 1.7 to 14.6 ascospores in 20 g of soil, but no ascospore was detected in the uninfested field soils. Ascospores were distributed more at 20cm of soil depth than at 10cm or 30cm of soil depth.

• Asian Journal of Turfgrass Science
• /
• v.8 no.1
• /
• pp.13-18
• /
• 1994

$CO_2$와 질소동화작용에 있어서의 잎과 줄기간의 세포간 관계가 잔디군락의 자연 환경 상태하에서 자라는 Portulaca oleracea 에서 조사되었다. 기공이 줄기에서는 관찰되지 않는 반면 잎에서는 $1cm^2$당 3,275개가 나타났다. 어린 쇠비름 잎의 기공의 조헝운 범에누누 높고 낮에는 낮다. 최고 활성을 갖는 마디의 순서는 위에서 아래로 떨어짐에 따라 변화한다.P.oleracea 의 줄기조직은 CMA의 최고 활성을 나타내었으나 잎에서는 CMA의 활성이 나타나지 않았다. 빠른 산의 성화는 새벽에 원줄기에서 보여지나 줄기는 서서히 증가하는 것 밖에 관찰되지 않는다. RuPB carboxy-lase의 활성은 거의 관찰 되지 않는다. 특히 잎새에서의 PEP carboxylase의 활성은 이른 아침에 줄기에서는 낮고 잎에서는 매우 높음을 보여준다. 이런 결과는 새벽에 열려진 기공을 통과할$CO_2$가 PEP carboxylase에 의해 잎에서 동화되고 $C_4$생산물이 줄기로 이동함을 나타낸다. Nitrate 축적과 nitrate reductase, nitrite reductase, glutamine symithetase, gluamate symthase, glutamade dehydrogenase의 농도는 잎보다 줄기에서 더 높았고 밤보다 낮에 더 높다. 이것은 뿌리를 통해 흡수된 nitrate의 상당한 양이 줄기에서 동화되고 줄기 조직을 통해 잎으로 이동되어 거기에서 감소된다.

• Bulletin of the Korean Space Science Society
• /
• 2010.04a
• /
• pp.32.4-32.4
• /
• 2010

Evolution of the Cosmos (ARCSEC). We have presented the evolutionary status of seven detached double line spectroscopic eclipsing binaries which are CD Tau, CM Lac, CW CMa, HS Hya, IT Cas, KM Hya, and ZZ Boo because the component stars in the binary systems still act as a single star. We determined the absolute dimensions of the binary systems using photometric and spectroscopic solutions by analyzing of the light curves and radial velocity curves. We chose evolutionary tracks of these binary systems. Using the luminosities, effective temperatures and masses. Finally we obtained ages and metallicity of the stars.

• Journal of the Korean Society of Food Culture
• /
• v.23 no.5
• /
• pp.595-604
• /
• 2008

This study was conducted to evaluate the menu of a Japanese restaurant in a first class tourism hotel. The calculations used for the menu analysis were conducted using MS Excel 2003. Several previous studies have been conducted to analyze menus. For example, Pavesic used of the weighted contribution margins (WCM) and potential food cost (PFC%) to evaluate menus, while Kasavana & Smith used the mix margin (MM%) and unit contribution margin (CM) to evaluate menus. The menu engineering method focused on the customer's viewpoints, while the Cost/Margin analysis method considered the manager's viewpoints. The menus that need continuous keeping Kasavana & Smith (Star) and Pavesic (Standard) included 'Assorted sashimi with side dishes (big), 'Lunch box special', 'Tempura course', 'Broiled Spanish mackerel and side dishes', 'Shrimp tempura', 'Special sushi', 'Seafood Udong', 'Buckwheat noodles'. The results of this study should increase customer satisfaction and profits at the Japanese Restaurant.

• Atmosphere
• /
• v.24 no.1
• /
• pp.1-15
• /
• 2014

This study compared ensemble mean and probability forecasts of snow depth amount associated with winter storm over South Korea on 28 December 2012 at five operational forecast centers (CMA, ECMWF, NCEP, KMA, and UMKO). And cause of difference in predicted snow depth at each Ensemble Prediction System (EPS) was investigated by using THe Observing system Research and Predictability EXperiment (THORPEX) Interactive Grand Global Ensemble (TIGGE) data. This snowfall event occurred due to low pressure passing through South Sea of Korea. Amount of 6 hr accumulated snow depth was more than 10 cm over southern region of South Korea In this case study, ECMWF showed best prediction skill for the spatio-temporal distribution of snow depth. At first, ECMWF EPS has been consistently enhancing the indications present in ensemble mean snow depth forecasts from 7-day lead time. Secondly, its ensemble probabilities in excess of 2~5 cm/6 hour have been coincided with observation frequencies. And this snowfall case could be predicted from 5-day lead time by using 10-day lag ensemble mean 6 hr accumulated snow depth distribution. In addition, the cause of good performances at ECMWF EPS in predicted snow depth amounts was due to outstanding prediction ability of forming inversion layer with below $0^{\circ}C$ temperature in low level (below 850 hPa) according to $35^{\circ}N$ at 1-day lead time.