• Title/Summary/Keyword: Spectrum Management

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Clinical Perspectives of Food Allergy in Infants and Young Children (영유아 식품알레르기의 임상적 조망)

  • Hwang, Jin-Bok
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.14 no.2
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    • pp.113-121
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    • 2011
  • Food allergies affect 7~8% of infants and young children, and their prevalence appears to have increased in recent years. Food allergy refers to an abnormal immunological reaction to a specific food. These reactions can be recurrent each time the food is ingested. Food allergy manifests itself with a wide spectrum of clinical characteristics including IgE-mediated diseases as immediate reactions, non-IgE-mediated disorders as delayed reactions, and mixed hypersensitivities. As a consequence, the clinical picture of a food allergy is pleomorphic. A well-designed oral food challenge is the most reliable diagnostic test for infants and young children whose clinical history and physical examination point towards a specific food allergy. Food specific IgE antibody tests (RAST, MAST, skin prick test, Uni-CAP, etc) are an alternative tool to determine oral food challenge for IgE-mediated disorders, but not for non-IgE-mediated allergies. Moreover, parents often impose their children on unnecessary diets without adequate medical supervision. These inappropriate dietary restrictions may cause nutritional deficiencies. This review aims to introduce clinical perspectives of food allergy in infants and young children and to orient clinicians towards different strains of diagnostic approaches, dietary management, and follow-up assessment of tolerance development.

Uncoordinated Dynamic Frequency Allocation Schemes based on Cognitive Radio in Mobile Cellular Networks (이동셀룰러망에서 무선 인지 기반 비협력 동적 주파수 자원 할당 기법)

  • Yu, Hyun;Jung, Jun-Woo;Lee, Jong-Kwan;Lim, Jae-Sung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.5
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    • pp.833-841
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    • 2011
  • In this paper, we propose uncoordinated dynamic frequency(channel) allocation schemes based on cognitive radio in mobile cellular networks(MCNs). Under the assumptions that mobile base stations are equipped with cognitive radio(CR) function and they construct uncoordinated network, the proposed scheme enables the MCNs by suppression of successive channel switching and management of channel allocation in a dynamic and distributed manner. The proposed scheme is composed of two phase processes. In the first phase, highly orthogonal sequences are generated and assigned to mobile base stations. In the second phase, each mobile base station is allocated a channel according to the pre-assigned orthogonal sequences. Simulation results show that the number of successive spectrum switching is reduced significantly compared with the random switching scheme.

Spatial Analysis on Marine Atmosphere Boundary Layer Features of SAR Imagery Using Empirical Mode Decomposition

  • Jo, Young-Heon;Oliveira, Gustavo Henrique;Yan, Xiao-Hai
    • Korean Journal of Remote Sensing
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    • v.33 no.4
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    • pp.351-358
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    • 2017
  • A new method to decompose the footprints of marine atmosphere boundary layer (MABL) on Synthetic Aperture Radar (SAR) imagery into characteristic spatial scales is proposed. Using two-dimensional Empirical Mode Decomposition (EMD) we obtain three Intrinsic Mode Functions (IMFs), which mainly present longitudinal rolls, three-dimensional cells and atmospheric gravity waves (AGW). The rolls and cells have spatial scales between 3.0 km and 3.8 km and between 5.3 km and 7.1 km, respectively. Based on previous observations and mixed-layer similarity theory, we estimated MABL's depths that vary from 0.95 km to 1.2 km over the rolls and from 3.0 km to 3.8 km over the cells. The AGW has maximum spectrum at 14.3 km wavelength. The method developed in this work can be used to decompose other satellite imageries into individual features through characteristic spatial scales.

Listeria Species in Broiler Poultry Farms: Potential Public Health Hazards

  • Dahshan, Hesham;Merwad, Abdallah Mohamed Amin;Mohamed, Taisir Saber
    • Journal of Microbiology and Biotechnology
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    • v.26 no.9
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    • pp.1551-1556
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    • 2016
  • Broiler meat production worldwide has been plagued by lethal food-poisoning bacteria diseases, including listeriosis. A fatality rate of 15.6% was recorded in human beings in the EU in 2015. During 2013, a total of 200 poultry farm samples, including litter, chicken breast, farm feed, and drinking water, were collected to generate baseline data for the characterization of the genus Listeria in broiler poultry farms. Listeria spp. were detected in a total of 95 (47.5%) poultry farm samples. The isolates of Listeria spp. included L. innocua (28.5%), L. ivanovii (12.5%), L. welshimeri (4.5%), and L. monocytogenes and L. seeligeri (1% each). Listeria spp. contamination rates were higher in farm feed (70%), followed by litter (52.5%), chicken breasts (42.2%), and drinking water (10%). Almost all Listeria spp. isolates were resistant to more than three classes of antibiotics (multidrug resistant). Besides this, we observed a significant resistance level to penicillin and fluoroquinolone drugs. However, lower resistance levels were recorded for broad-spectrum cephalosporins. The inlA, inlC, and inlJ virulence genes were detected in almost all of the L. monocytogenes isolates. Thus, food safety management approaches and interventions at all stages of the broiler rearing cycle were needed to control cross-contamination and the zoonotic potential of listeriosis.

Multi-Mode Precoding Scheme Based on Interference Channel in MIMO-Based Cognitive Radio Networks

  • Jung, Minchae;Hwang, Kyuho;Choi, Sooyong
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2011.07a
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    • pp.137-140
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    • 2011
  • A precoding strategy is one of the representative interference management techniques in cognitive radio (CR) network which is a typical interference-limited environment. The interference minimization approach to precoding is an appropriate scheme to mitigate the interference efficiently while it may cause the capacity loss of the desired channel. The precoding scheme for the maximal capacity of the desired channel improves the capacity of the desired channel while it increases the interference power and finally causes the capacity loss of the interfered users. Therefore, we propose a precoding scheme which satisfies these two conflicting goals and manages the interference signal in such an interference-limited environment. The proposed scheme consists of two steps. First, the precoder nulls out the largest singular value of the interference channel to mitigate the dominant interference signal based on the interference minimization approach. Second, the transmitter calculates the sum capacities per mode and selects a mode to maximize the sum capacity. In the second step, each mode consists of the right singular vectors corresponding to the singular values except the largest singular value eliminated in the first step. Simulation results show that the proposed precoding scheme not only efficiently mitigate the interference signal, but also has the best performance in terms of the sum capacity in a MIMO-based CR network.

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Interference Assessment between Radio-Navigation Satellite Service and Mobile Communication Service in Adjacent L-Band (L-대역 무선항행위성업무와 이동업무간 인접대역 간섭 평가)

  • Jeong, Namho;Oh, Dae-Sub;Ku, Bon-Jun
    • Journal of Satellite, Information and Communications
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    • v.8 no.4
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    • pp.58-63
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    • 2013
  • Since radio interference can degrade the performance of systems or limit the system operation, an accurate assessment of radio interference with the existing systems should be conducted prior to the operation of a new system. In this paper, we present an evaluation methodology for the radio interference between radio-navigation satellite service (RNSS) systems and mobile communication service (MS) system. Radio interferences from RNSS systems into MS system using minimum coupling loss (MCL) method are simulated and vice-versa, and the frequency sharing condition between two systems are derived in a same geographical area.

PERFORMANCE OF RAINBOW TROUT (Oncorhynchus mykiss) FED ON DIFFERENT DIETARY PROTEIN WITH FIXED ENERGY RATIO

  • Mahmud, S.;Chakraborty, S.C.;Das, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.9 no.1
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    • pp.31-35
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    • 1996
  • An experiment was conducted on rainbow trout(Oncorhynclus mykiss) for eight weeks to investigate the growth performance of the fish fed with different dietary protein with constant diet energy of $20kJg^{-1}$. Four diets containing 25, 30, 35 and 40% crude protein were used. The highest mean final weight was obtained for the fish fed with diet having 35% protein. Growth performance in terms of Specific Growth Rate (SGR), Food Conversion Ratio (FCR) and Protein Efficiency Ratio (PER) were calculated for each diet. There were no significant differences in SGR but the highest value was exhibited by fish fed with 35% protein diet. Significant differences were found among FCR of different diets. Diets with 35 and 40% crude protein gave better FCR value than that of 25 and 30% crude protein. Although significant differences were not found between PER of different diets but PER of diet with 35% protein was found to be better than PER of both high and low protein diets (diets of 40 and 30% crude protein). It is concluded that diet having 35% protein with protein energy ratio of $17.53mgkJ^{-1}$ was suitable for rainbow trout (O. mykiss) among the protein spectrum used.

An Efficient Code Assignment Algorithm in Wireless Mesh Networks (무선 메쉬 네트워크에서의 효율적인 코드할당 알고리즘에 대한 연구)

  • Yeo, Jae-Hyun
    • Journal of Information Technology Applications and Management
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    • v.15 no.1
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    • pp.261-270
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    • 2008
  • Wireless Mesh Networks (WMNs) have emerged as one of the new hot topics in wireless communications. WMNs have been suggested for use in situations in which some or all of the users are mobile or are located in inaccessible environments. Unconstrained transmission in a WMN may lead to the time overlap of two or more packet receptions, called collisions or interferences, resulting in damaged useless packets at the destination. There are two types of collisions; primary collision, due to the transmission of the stations which can hear each other, and hidden terminal collision, when stations outside the hearing range of each other transmit to the same receiving stations. For a WMN, direct collisions can be minimized by short propagation and carrier sense times. Thus, in this paper we only consider hidden terminal collision while neglecting direct collisions. To reduce or eliminate hidden terminal collision, code division multiple access (CDMA) protocols have been introduced. The collision-free property is guaranteed by the use of spread spectrum communication techniques and the proper assignment of orthogonal codes. Such codes share the fixed channel capacity allocated to the network in the design stage. Thus, it is very important to minimize the number of codes while achieving a proper transmission quality level in CDMA WMNs. In this paper, an efficient heuristic code assignment algorithm for eliminating hidden terminal collision in CDMA WMNs with general topology.

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Time-Frequency Feature Extraction of Broadband Echo Signals from Individual Live Fish for Species Identification (활어 개체어의 광대역 음향산란신호로부터 어종식별을 위한 시간-주파수 특징 추출)

  • Lee, Dae-Jae;Kang, Hee-Young;Pak, Yong-Ye
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.49 no.2
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    • pp.214-223
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    • 2016
  • Joint time-frequency images of the broadband acoustic echoes of six fish species were obtained using the smoothed pseudo-Wigner-Ville distribution (SPWVD). The acoustic features were extracted by changing the sliced window widths and dividing the time window by a 0.02-ms interval and the frequency window by a 20-kHz bandwidth. The 22 spectrum amplitudes obtained in the time and frequency domains of the SPWVD images were fed as input parameters into an artificial neural network (ANN) to verify the effectiveness for species-dependent features related to fish species identification. The results showed that the time-frequency approach improves the extraction of species-specific features for species identification from broadband echoes, compare with time-only or frequency-only features. The ANN classifier based on these acoustic feature components was correct in approximately 74.5% of the test cases. In the future, the identification rate will be improved using time-frequency images with reduced dimensions of the broadband acoustic echoes as input for the ANN classifier.

Apoptosis of Colorectal Cancer UTC116 Cells Induced by Cantharidinate

  • Liu, Bin;Gao, Hai-Cheng;Xu, Jing-Wei;Cao, Hong;Fang, Xue-Dong;Gao, Hai-Mei;Qiao, Shi-Xing
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.8
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    • pp.3705-3708
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    • 2012
  • Effects of Cantharidinate on apoptosis of human colorectal cancer UTC-116 cells were investigated by means of 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, H and E staining, flow cytometry, and Raman Spectra analysis. The results showed Cantharidinate to exert inhibitory action on proliferation of human colorectal cancer UTC-116 cells, inducing apoptosis, arresting cells in G1 phase, with decline of S and G2 phases. In addition, the results of Raman spectrum showed significant changes in the UTC-116 cells chemical structure with stretching after the application of Cantharidinate. Taken together, these results suggest that the treatment of human colorectal cancer with Cantharidinate may be associated with multiple molecular mechanisms for apoptosis. Furthermore, similar to fluorouracil, Cantharidinate should be considered as novel assistant drug for controlling the growth of human colorectal cancer UTC-116 cells.