37 research outputs found

    AMC with predicted CQI in packet-based wireless systems

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    In a packet based wireless system, an adaptive modulation and coding (AMC) scheme is often employed with the use of channel quality information (CQI). However, the AMC can be operated improperly due to delayed CQI, causing performance degradation. In this paper, we consider the use of predicted CQI for the AMC considering the feedback delay and channel characteristics. We also consider the use of a hybrid automatic repeat request scheme with the proposed AMC for further improvement in high mobility environments.the Ministry of Information & Communications, Korea, under the Information Technology Research Center (ITRC) Progra

    Effective SNR Based MIMO Switching in Mobile WiMAX Systems

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    The mobile WiMAX system considers the use of (2×2) multiple-input multiple-output (MIMO) schemes for performance improvement. It is required for mobile stations to appropriately switch the MIMO mode; space– time block code (STBC) or vertical spatial multiplexing (VSM). In this paper we consider a novel switching scheme for the MIMO mode based on effective signal-tonoise ratio. Assuming the use of a minimum mean square error (MMSE) receiver for the VSM and a maximum ratio combining receiver for the STBC, the threshold for the mode switching is analytically derived in a closed form. Simulation results show that the proposed switching scheme outperforms conventional switching schemes in terms of the capacity and outage probability

    Introduction of Transmembrane Inner Ear (tmie) Gene Can Recover the Hearing Impairment and Abnormal Behavior in the Circling Mouse

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    The spontaneous mutant circling mouse (cir/cir) shows a circling behavior and hearing loss. We produced transgenic mice overexpressing the causative gene, transmembrane inner ear (tmie), for the phenotypic rescue of the circling mouse. Through the continuous breeding with circling mice, the cir/cir homozygous mice carrying the transgene (cir/cir-tg) were produced. The rescued cir/cir -tg mice were able to swim in the water with proper orientation and did not show any circling behavior like wild type mice. Western blot and immunohistochemical analysis exhibited that the transgenic tmie was expressed in the inner ear. Inner and outer hair cells were recovered in the cochlea and spiral ganglion neurons were also recovered in the rescued mice. Auditory brainstem response (ABR) test demonstrated that the cir/cir -tg mice are able to respond to sound. This study demonstrates that tmie transgene can recover the hearing impairment and abnormal behavior in the circling mouse

    Interferometric Fiber Optic Sensors

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    Fiber optic interferometers to sense various physical parameters including temperature, strain, pressure, and refractive index have been widely investigated. They can be categorized into four types: Fabry-Perot, Mach-Zehnder, Michelson, and Sagnac. In this paper, each type of interferometric sensor is reviewed in terms of operating principles, fabrication methods, and application fields. Some specific examples of recently reported interferometeric sensor technologies are presented in detail to show their large potential in practical applications. Some of the simple to fabricate but exceedingly effective Fabry-Perot interferometers, implemented in both extrinsic and intrinsic structures, are discussed. Also, a wide variety of Mach-Zehnder and Michelson interferometric sensors based on photonic crystal fibers are introduced along with their remarkable sensing performances. Finally, the simultaneous multi-parameter sensing capability of a pair of long period fiber grating (LPG) is presented in two types of structures; one is the Mach-Zehnder interferometer formed in a double cladding fiber and the other is the highly sensitive Sagnac interferometer cascaded with an LPG pair

    Intralymphatic immunotherapy with tyrosine-adsorbed allergens: a double-blind, placebo-controlled trial

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    Background Most previous studies used aluminum hydroxide-absorbed allergen extracts in evaluating the potential therapeutic roles of intralymphatic allergen-specific immunotherapy (ILAIT). In this study, we evaluated the therapeutic efficacy and safety of ILAIT with L-tyrosine-adsorbed allergen extracts of Dermatophagoides farinae, D. pteronyssinus, cat, dog, or mixtures thereof, in patients with allergic rhinitis induced by these allergens. Methods In this randomized, double-blind, placebo-controlled trial, study subjects received three intralymphatic injections of L-tyrosine-adsorbed allergen extracts (active group) or saline (placebo group) at 4-week intervals. Results Although ILAIT reduced daily medication use and skin reactivity to HDM and cat allergens at 4 months after treatment, overall symptom score on a visual analog scale (VAS), sinonasal outcome test-20 (SNOT-20), rhinoconjunctivitis quality of life questionnaire (RQLQ), daily symptom score (dSS), daily medication score (dMS), daily symptom medication score (dSMS), nasal reactivity to HDM allergen, and basophil activity to HDM, cat, and dog allergens at 4 months and 1 year after treatment were similar between the treatment and control groups. Intralymphatic injection was more painful than a venous puncture, and pain at the injection site was the most frequent local adverse event (12.8%); dyspnea and wheezing were the most common systemic adverse events (5.3%). Conclusions ILAIT with L-tyrosine-adsorbed allergen extracts does not exhibit profound therapeutic efficacy in allergic rhinitis and can provoke moderate-to-severe systemic reactions and cause pain at the injection site. Trial registration: clinicaltrials.gov: NCT02665754; date of registration: 28 January 2016This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (NRF-2015R1D1A1A02061943). The funders had no role in the design of the study and collection, analysis, and interpreta‑tion of data and in writing the manuscript. The authors have no other fnancial relationships relevant to this article to disclose

    Transport Performance Simulation of Separating System for Self–propelled Peanut Harvester using EDEM Software

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    This study evaluated a DEM (Discrete Element Method) model through test results and analysis results for the simulation of the conveying performance of the separating system in a peanut harvester. With the validated DEM model, analysis under three conditions of slope angle of separating system compare with horizon (–7°, 0°, and 7°) was also conducted to examine the conveying performance. From the comparison between the test results and simulation results, the conveying performances of 0° and 7° were observed to be the same at the initial period and completion period; however, the gradient of 0° and 7° from the simulation were higher than the ones from the test by 8.9% (0°) and 9.2% (7°). The higher gradient means that the transport performance is better. The gradient of –7° from the simulation was higher than the one from the test by 3.6%, and the amount of the peanuts from the simulation was larger than the test by 500 g at the initial period of 5 seconds. The higher gradient of the simulation was due to the losses at the collecting part as 3.4% (0°), 3.1% (7°), and 2.0% (–7°). The error in the amount of the peanuts (500 g) at the initial period of 5 seconds with –7° was due to the initial input difference between the test and simulation
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