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Estimation of ecological flow and fish habitats for Andong Dam downstream reach using 1-D and 2-D physical habitat models (1차원 및 2차원 물리서식처 모형을 활용한 안동댐 하류 하천의 환경생태유량 및 어류서식처 추정)

  • Kim, Yongwon;Lee, Jiwan;Woo, Soyoung;Kim, Soohong;Lee, Jongjin;Kim, Seongjoon
    • Journal of Korea Water Resources Association
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    • v.55 no.12
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    • pp.1041-1052
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    • 2022
  • This study is to estimate the optimal ecological flow and analysis the spatial distribution of fish habitat for Andong dam downstream reach (4,565.7 km2) using PHABSIM (Physical Habiat Simulation System) and River2D. To establish habitat models, the cross-section informations and hydraulic input data were collected uisng the Nakdong river basic plan report. The establishment range of PHABSIM was set up about 410.0 m from Gudam streamflow gauging station (GD) and about 6.0 km including GD for River2D. To select representative fish species and construct HSI (Habitat Suitability Index), the fish survey was performed at Pungji bridge where showed well the physical characteristics of target stream located downstream of GD. As a result of the fish survey, Zacco platypus was showed highly relative abundance resulting in selecting as the representative fish species, and HSI was constructed using physical habitat characteristics of the Zacco platypus. The optimal range of HSI was 0.3~0.5 m/s at the velocity suitability index, 0.4~0.6 m at the depth suitability index, and the substrate was sand to fine gravel. As a result of estimating the optimal ecological flow by applying HSI to PHABSIM, the optimal ecological flow for target stream was 20.0 m3/sec. As a result of analysis two-dimensional spatial analysis of fish habitat using River2D, WUA (Weighted Usable Area) was estimated 107,392.0 m2/1000 m under the ecological flow condition and it showed the fish habitat was secured throughout the target stream compared with Q355 condition.

Forest Stand Structure, Site Characteristics and Carbon Budget of the Kwangneung Natural Forest in Korea (광릉 활엽수천연림의 산림식생구조, 입지환경 및 탄소저장량)

  • Jong-Hwan Lim;Joon Hwan Shin;Guang Ze Jin;Jung Hwa Chun;Jeong Soo Oh
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.5 no.2
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    • pp.101-109
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    • 2003
  • The study area, Kwangneung Experiment Forest (KEF) is located on the west-central portion of Korean peninsula and belongs to a cool-temperate broadleaved forest Bone. At the old-growth deciduous forest near Soribong-peak (533.1 m) in KEF, we have established a 1 ha permanent plot ($100m{\times}100m$) and a flux tower, and the site was registered as a KLTER(Korean long-term ecological research network) and DK site of KoFlux. In this site, we made a stemmap of trees and analyzed forest stand structure and physical and chemical soil characteristics, and estimated carbon budgets by forest components (tree biomass, soils, litter and so on). Dominant tree species were Quercus serrata and Carpinus laxiflora, and accompanied by Q. aliena, Carpinus cordata, and so on. As a result of a field survey of the plot, density of the trees larger than 2 cm in DBH was 1,473 trees per ha, total biomass 261.2 tons/ha, and basal area $28.0m^2$/ha. Parent rock type is granite gneiss. Soil type is brown forest soil (alfisols in USDA system), and the depth is from 38 to 66 cm. Soil texture is loam or sandy loam, and its pH was f개m 4.2 to 5.0 in the surface layer, and from 4.8 to 5.2 in the subsurface layer. Seasonal changes in LAI were measured by hemispherical photography at the 1.2 m height, and the maximum was 3.65. And the spatial distributions of volumetric soil moisture contents and LAIs of the plot were measured. The carbon pool in living tree biomass including below ground biomass was 136 tons C/ha, and 5.6 tons C/ha is stored in the litter layer, and about 92.0 tons C/ha in the soil to the 30 cm in depth. Totally more than about 233.6 tons C/ha was stored in DK site. These ground survey and monitoring data will give some important parameters and validation data for the forest dynamics models or biogeochemical dynamics models to predict or interpolate spatially the changes in forest ecosystem structure and function.

A Case Study of Spatial CAD Education in Blended Learning Environment (혼합형 학습(Blended Learning) 환경에서의 공간디자인 CAD 수업 사례연구)

  • Hwang, Ji Hyoun;Lim, Haewon
    • The Journal of the Korea Contents Association
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    • v.21 no.10
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    • pp.115-126
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    • 2021
  • The purpose of this study is to closely analyze the case of blended-learning in order to provide a diverse and flexible learning environment while maintaining the nature of face-to-face classes, and to identify the learning environment that supports blended-learning in each class step and the educational experience of students. The experience and satisfaction of blended learning were investigated in various ways: course evaluation, LMS activity evaluation, and questionnaire before and after the class. As a result, the blended-learning is better than the traditional face-to-face classes, in providing real-time feedback, opportunities for various interactions, and textual conversations, anytime and anywhere. In addition, as a result of the preliminary survey, as a measure to solve the opinion that concentration was reduced due to problems such as networks and felt uncomfortable in the communication part, the theory and lectures of the design practice class were conducted non-face-to-face. The individual Q&A and feedback were conducted face-to-face and non-face-to-face. As a result of the follow-up survey, it was found that concentration and efficiency could be improved. This opens up possibilities for active use of the online environment in design practice classes.

Sorption Efficiency of the Bamboo Charcoal to Remove the Cesium in the Contaminated Water System (오염수계 내 세슘 제거를 위한 대나무 활성탄의 흡착효율 규명)

  • Ahn, Joungpil;Lee, Minhee
    • Economic and Environmental Geology
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    • v.51 no.2
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    • pp.87-97
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    • 2018
  • The cesium (Cs) removal from the contaminated water system has been considered to be difficult because the cesium likes to exist as soluble phases such as ion and complexes than the solid in water system. Many researches have focused on developing the breakthrough adsorbent to increase the cesium removal efficiency in water. In this study, the laboratory scale experiments were performed to investigate the feasibility of the adsorption process using the bamboo charcoal for the Cs contaminated water system. The Cs removal efficiency of the bamboo charcoal were measured and the optimal adsorption conditions were determined by the adsorption batch experiments. Total 5 types of commercialized bamboo charcoals in Korea were used to identify their surface properties from SEM-EDS and XRD analyses and 3 types of bamboo charcoals having large specific surface areas were used for the adsorption batch experiment. The batch experiments to calculate the Cs removal efficiency were performed at conditions of various Cs concentration (0.01 - 10 mg/L), pH (3 - 11), temperature ($5-30^{\circ}C$), and adsorption time (10 - 120 min.). Experimental results were fitted to the Langmuir adsorption isotherm curve and their adsorption constants were determined to understand the adsorption properties of bamboo charcoal for Cs contaminated water system. From results of SEM-EDS analyses, the surfaces of bamboo charcoal particles were composed of typical fiber structures having various pores and dense lamella structures in supporting major adsorption spaces for Cs. From results of adsorption batch experiments, the Cs-133 removal efficiency of C type bamboo charcoal was the highest among those of 3 bamboo charcoal types and it was higher than 75 % (maximum of 82 %) even when the initial Cs concentration in water was lower than 1.0 mg/L, suggesting that the adsorption process using the bamboo charcoal has a great potential to remove Cs from the genuine Cs contaminated water, of which Cs concentration is low (< 1.0 mg/L) in general. The high Cs removal efficiency of bamboo charcoal was maintained in a relatively wide range of temperatures and pHs, supporting that the usage of the bamboo charcoal is feasible for various types of water. Experimental results were similar to the Langmuir adsorption model and the maximum amount of Cs adsorption (qm:mg/g) was 63.4 mg/g, which was higher than those of commercialized adsorbents used in previous studies. The surface coverage (${\theta}$) of bamboo charcoal was also maintained in low when the Cs concentration in water was < 1.0 mg/L, investigating that the Cs contaminated water can be remediated up with a small amount of bamboo charcoal.

How to Prepare Rehmanniae Radix Preparata Described in the 『Treasured Mirror of Eastern Medicine』 (『東醫寶鑑』의 熟地黃 제조방법)

  • Roh, Jong Seong;Yoon, Michung;Shin, Soon Shik
    • Herbal Formula Science
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    • v.24 no.1
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    • pp.17-30
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    • 2016
  • Objectives Rehmanniae Radix Preparata was prepared in the traditional Rehmanniae Radix Preparata preparation method set forth in the 『Treasured Mirror of Eastern Medicine(Donguibogam)』 with a view to measuring the contents of 5-Hydroxymethyl-2-furaldehyde(5-HMF) at individual stages of steaming and sundrying and identifying new chemical components.Methods Based on the traditional Rehmanniae Radix Preparata preparation method set forth in the 『Treasured Mirror of Eastern Medicine』, Rehmanniae Radix Preparata steamed and sundried once through nine times was prepared. Thereafter, 5-HMF contents were analyzed and new chemical components were identified in the Rehmanniae Radix Preparata using Waters HPLC e2695, 2640 detectors, a Waters Acquity UPLC system, and a Micromass Q-TOF Premier mass spectrometer.Results The Rehmanniae Radix Preparata preparation method set forth in the 『Treasured Mirror of Eastern Medicine』 is a unique preparation method in Republic of Korea different from that in China. In the first stage of the method, fresh Rehmanniae Radix Crudus was divided into high quality, medium quality, and low quality ones named Rehmanniae Radix Crudus (Caelum)(天黃), Rehmanniae Radix Crudus (Homo)(人黃), and Rehmanniae Radix Crudus (Terra)(地黃) respectively to use Rehmanniae Radix Crudus (Caelum) and Rehmanniae Radix Crudus (Homo) for preparation of juice while using Rehmanniae Radix Crudus (Terra) to make Rehmanniae Radix Preparata. In the second stage, Rehmanniae Radix Crudus (Caelum) and Rehmanniae Radix Crudus (Terra) were made into juice and Rehmanniae Radix Crudus (Terra) was soaked in the juice. In the third stage, among auxiliary materials, rice wine named Purum Vinum Oryzae(淸酒) brewed from sticky rice was sprinkled on Rehmanniae Radix Crudus (Terra) to the extent that Rehmanniae Radix Crudus (Terra) became wet. In the fourth stage, Rehmanniae Radix Preparata steamed in earthenware steamer was dried under natural sunlight. The contents of 5-HMF in Rehmanniae Radix Preparata steamed and sundried once through nine times were shown to be below 0.1% in all cases. Pomolic acid was identified as a new chemical component.Conclusions In conclusion, the Rehmanniae Radix Preparata preparation method set forth in the 『Treasured Mirror of Eastern Medicine』 is thought to be a unique preparation method in South Korea in which Rehmanniae Radix Preparata is completed through the first stage in which fresh Rehmanniae Radix Crudus collected from fields is divided into high, medium, and low quality ones and fresh Rehmanniae Radix Crudus juice is made, the second stage in which the high quality fresh Rehmanniae Radix Crudus is soaked in the fresh Rehmanniae Radix Crudus juice, the third stage in which the fresh Rehmanniae Radix Crudus is steamed, and the fourth stage in which the steamed Rehmanniae Radix Crudus is dried.

Stage specific transcriptome analysis of liver tissue from a crossbred Korean Native Pig (KNP × Yorkshire)

  • Kumar, Himansu;Srikanth, Krishnamoorthy;Park, Woncheol;Lee, Kyung-Tai;Choi, Bong-Hwan;Kim, Jun-Mo;Lim, Dajeong;Park, Jong-Eun
    • Journal of Biomedical and Translational Research
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    • v.19 no.4
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    • pp.116-124
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    • 2018
  • Korean Native Pig (KNP) has a uniform black coat color, excellent meat quality, white colored fat, solid fat structure and good marbling. However, its growth performance is low, while the western origin Yorkshire pig has high growth performance. To take advantage of the unique performance of the two pig breeds, we raised crossbreeds (KNP ${\times}$ Yorkshire to make use of the heterotic effect. We then analyzed the liver transcriptome as it plays an important role in fat metabolism. We sampled at two stages: 10 weeks and at 26 weeks. The stages were chosen to correspond to the change in feeding system. A total of 16 pigs (8 from each stage) were sampled and RNA sequencing was performed. The reads were mapped to the reference genome and differential expression analysis was performed with edgeR package. A total of 324 genes were found to be significantly differentially expressed (${\left|log2FC\right|}$ > 1 & q < 0.01), out of which 180 genes were up-regulated and 144 genes were down-regulated. Principal Component Analysis (PCA) showed that the samples clustered according to stages. Functional annotation of significant DEGs (differentially expressed genes) showed that GO terms such as DNA replication, cell division, protein phosphorylation, regulation of signal transduction by p53 class mediator, ribosome, focal adhesion, DNA helicase activity, protein kinase activity etc. were enriched. KEGG pathway analysis showed that the DEGs functioned in cell cycle, Ras signaling pathway, p53 signaling pathway, MAPK signaling pathway etc. Twenty-nine transcripts were also part of the DEGs, these were predominantly Cys2His2-like fold group (C2H2) family of zinc fingers. A protein-protein interaction (PPI) network analysis showed that there were three highly interconnected clusters, suggesting an enrichment of genes with similar biological function. This study presents the first report of liver tissue specific gene regulation in a cross-bred Korean pig.

Anatomical Studies on Root Formation in Hypocotyl and Epicotyl Cuttings of Woody Plants (임목(林木)의 배축(胚軸) 및 유경삽수발근(幼茎揷穗発根)의 해부학적(解剖学的) 연구(研究))

  • Choi, Man Bong
    • Journal of Korean Society of Forest Science
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    • v.52 no.1
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    • pp.1-30
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    • 1981
  • The origin and development of adventitious roots was studied using hypocotyl and epicotyl cuttings of 34 species, 24 genus of woody plants. These cuttings obtained from young seedlings cultured in vials containing distilled water only. The several characteristics of cuttings materials studied are shown in Table 1. The results are summerized as follows: 1. The circumference shapes of cross-sections of hypocotyl and epicotyl cuttings can be divided into six categories, namely, round, irregular round, ellipse, irregular ellipse, square, and triangle. Species differences within a genus did not show any difference of hypocotyl and epicotyl cross-sections shape, however, a noticeable variation among genus or higher taxa. 2. The arrangements of vascular bundles in the cross-sections of hypocotyls or epicotyls were almost all collateral types and generally showed generic characteristics differing one to the other. However, there were some variations between species within the genus. Six models of vascular bundle arrangement were proposed for all the above speices. 3. The rooting portions of hypocotyl and epicotyl cuttings in this experimental materials can be grouped as follows: (1) Interfascicular parenchyma; (Thuja orientalis. T. orientalis for. sieboldii, Acer microsieboldianum, A. palmatum, A. saccharinum, Cercis chinensis, Lespedeza bicolor, Magnolia obovata, M. sieboldii, Mallotus japonicus, Staphylea bumalda) (2) Cambial and phloem parenchyma: (Chamaecyparis obtusa, C. pisifera, Albizzia julibrissin, Buxus microphylla var. Koreana, Cereis chinensis, Euonymus japonica, Firmiana platanifolia, Lagerstroemia indica, Ligustrum salicinum, L. obtusifolium, Magnolia kobus, M. obovata, Mallotus japonicus, Morus alba, Poncirus trifoliata, Quercus myrsinaefolia, Rosa polyantha, Styrax japonica, Styrax obassia) (3) Primary ray tissues; (Euonymus japonica, Styrax japonica) (4) Leaf traces; (Quercus acutissima, Q. aliena) (5) Cortex parenchyma; (Ailanthus altissima) (6) Callus tissues; (Castanea crenata, Quercus aliena, Q. myrsinaefolia, Q. serrata) 4. As a general tendency throughout the species studied, in hypocotyl cuttings, the adventitious root primordia were originated from the interfascicular parenchyma tissue, however, leaf traces and callus tissues were contributed to the root primordia formation in epicotyl cuttings. The hypocotyl cuttings of Ailanthus altissima exhibited a special performance in the root primordia formation, this means that cortex parenchyma was participated to the origin tissue. And in Firmiana platanifolia, differening from the other most species, the root primordia were formed at the phloem parenchyma adjacent outwardly to xylem tissue of vascular bundle system as shown photo. 48. 5. All the easy-to, or difficult-to root species developed adventitious roots in vials filled with distilled water. In the difficult-to-root species, however, root formations seemed to be delayed because they almost all had selerenchyma or phloem fiber which gave some mechanical hindrance to protrusion of root primordia. On the other hand, in the easy-to-root species they seemed to form them more easily because they did not have the said tissues. The rooting portions between easy-to-root and difficult-to-root species have not clearly been distinguished, and they have multitudinous variations. 6. The species structured with the more vascular bundles in number compared with the less vascular bundles exhibited delayed rooting. In the cuttings preparation, the proximal end of cuttings was closer to root-to-stem transition region, the adventitious root formation showed easier. 7. A different case occured however with the mature stem cuttings, in both the needle-leaved and the broad-leaved species. In the hypocotyl cuttings, parenchymatous tissues sited near the vascular bundles become the most frequent root forming portions in general and relevant distinctions between both species were hardly recognizable. 8. In the epicotyl cuttings, root primordia originated mainly in leaf traces in connection with cambial and phloems or callus tissues itself. In the hypocotyl cuttings, interfascicular parenchyma was the most frequent portion of the root primordia formation. The portions of root primordia had more connection with vascular cambium system, as the tissues were continuing to be developed.

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키토산 분자량 변화에 따른 수중의 여러 중금속들의 제거에 관한 연구

  • 이승원;김동석
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2003.05a
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    • pp.292-296
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    • 2003
  • Autoclaving처리를 하지 않은 키토산과 autoclaving처리한 키토산과의 중금속 흡착실험을 해 본 결과 다음과 같은 결과를 도출 할 수 있었다. 1) 먼저 중금속간의 흡착능을 고찰하기 위하여 Langmuir와 Freundlich 흉착등온식에 적용시켜 본 결과 Freundlich 흡착등온식 보다는 Langmuir 흡착등온식이 보다 적합한 것으로 나타났다. 2) 시간에 따라서 autoclaving 처리한 키토산의 중금속 제거 가능성과 그 효율을 검토하기 위하여 각 중금속간의 Langmuir 흡착등온식을 이용하여 $q_{max}$를 나타냈다. 15 min > 60 min > 0 min 순으로 모든 중금속 제거 실험에서 15 min 동안 autoclaving 처리한 키토산의 중금속 흡착량이 가장 높은 것으로 나왔다. 그러므로 기존의 키토산 보다는 15 min동안 autoclaving 처리한 키토산이 중금속 제거에 더 좋은 흡착제로써 역할을 할 수 있을 것으로 판단된다. 3) 키토산을 이용한 중금속 제거에서는 $Pb^{2+}$ > $Cd^{2+}$ > $Cu^{2+}$ > $Cr^{3+}$순서로 제거가 되었다. 여러 연구자들의 실험 결과를 종합해 볼 때 Pb$^{2+}$가 중금속 중에 제거가 잘 된다는 연구 결과가 많이 발표 되었으며, $Cd^{2+}$, $Cu^{2+}$, $Cr^{3+}$의 경우에는 흡착제의 종류에 따라서 제거되는 순서가 다르다는 연구 결과들이 보고 되고 있다. 그러나 어떠한 이유로 중금속의 제거에 차이가 있는지에 대해서는 명확한 결론이 내려져 있지 않는 실정이다. 이러한 중금속간의 경쟁적인 관계에 대해 더 많은 세밀한 연구가 이루어져야 할 것 같다.는 0.52mg/$\ell$~0.99mg/$\ell$~의 범위이었다. 신천에 금호강물을 혼합한 이후에도 부유물질, 생화학적산소요구량, 암모니아태 질소, 총인 등의 농도가 개선되지 않았다. 즉 금호강물의 혼합은 신천수질환경사업소에서 배출되는 방류수에 함유되어 있을 2차 오염물질의 희석이라는 이점외의 수질개선효과는 확인되지 않았다.l years and a new type of transfer crane has been developed. Design concepts and control methods of a new crane will be introduced in this paper.and momentum balance was applied to the fluid field of bundle. while the movement of′ individual material was taken into account. The constitutive model relating the surface force and the deformation of bundle was introduced by considering a representative prodedure that stands for the bundle movement. Then a fundamental equations system could be simplified considering a steady state of the process. On the basis of the simplified model, the simulation was performed and the results could be confirmed by the experiments under various conditions.뢰, 결속 등 다차원의 개념에 대한 심도 깊은 연구와 최근 제기되고 있는 이론

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Descending Controls: The Self-Regulation of Chronic Pain (하행성 조절계 : 만성 통증에 대한 제어 작용)

  • Kim, Min-Jae;Kang, Soo-Kyung;Chun, Yang-Hyun;Hong, Jung-Pyo;Auh, Q-Schick
    • Journal of Oral Medicine and Pain
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    • v.38 no.2
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    • pp.215-219
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    • 2013
  • The descending control system is composed of a group of structures in the midbrain, medulla oblongata and pons that form a network of descending inhibitory projections. In the clinical setting, it has been shown that the application of a electrical counterirritant to these structures and diminishes the pain in patients. Thus, depression and anxiety have been shown to predict the development of chronic neuropathic pain state. These factors could influence pain might also involve descending controls. Interestingly, reduced descending controls are seen in patients with irritable bowel syndrome and theses patients had greater anxiety, depression compared to controls. And, the influence of anxiety on the chronicity of pain and on the descending control pathways should be tested in animal models, using modern techniques. Given this Knowledge, it is no wonder that pain is a highly personal experience that is susceptible to a variety of biologic, pharmacologic, and environmental influences.

A Compressed Sensing-Based Signal Detection Technique for Generalized Space Shift Keying Systems (일반화된 공간천이변조 시스템에서 압축센싱기술을 이용한 수신신호 복호 알고리즘)

  • Park, Jeonghong;Ban, Tae Won;Jung, Bang Chul
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.7
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    • pp.1557-1564
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    • 2014
  • In this paper, we propose a signal detection technique based on the parallel orthogonal matching pursuit (POMP) is proposed for generalized shift space keying (GSSK) systems, which is a modified version of the orthogonal matching pursuit (OMP) that is widely used as a greedy algorithm for sparse signal recovery. The signal recovery problem in the GSSK systems is similar to that in the compressed sensing (CS). In the proposed POMP technique, multiple indexes which have the maximum correlation between the received signal and the channel matrix are selected at the first iteration, while a single index is selected in the OMP algorithm. Finally, the index yielding the minimum residual between the received signal and the M recovered signals is selected as an estimate of the original transmitted signal. POMP with Quantization (POMP-Q) is also proposed, which combines the POMP technique with the signal quantization at each iteration. The proposed POMP technique induces the computational complexity M times, compared with the OMP, but the performance of the signal recovery significantly outperform the conventional OMP algorithm.