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81.
The error probability of reduced-state sequence estimation (RSSE) for trellis-coded modulation (TCM) on intersymbol interference channels is evaluated. A method based on a stack algorithm is proposed to evaluate the union bound on the error probability for ideal RSSE, which is a good approximation to the error probability of real RSSE. The stack algorithm is employed because it provides a good tradeoff between computer memory and computing time 相似文献
82.
Broadband tapered microstrip leaky-wave antenna 总被引:1,自引:0,他引:1
Wanchu Hong Tai-Lee Chen Chi-Yang Chang Sheen J.-W. Yu-De Lin 《Antennas and Propagation, IEEE Transactions on》2003,51(8):1922-1928
This study proposes a novel scheme based on the characteristics of leaky-wave antennas for the empirical design of broadband tapered microstrip leaky-wave antennas. This scheme can explain and approximately model the radiation characteristics of a linearly tapered leaky-wave microstrip antenna. A broadband feeding structure that uses the balanced and the inverted balanced microstrip lines to form a pair of broadband baluns is also presented. The measured return loss of the inverted balanced microstrip lines has a VSWR/spl les/2 from dc to 18.6 GHz and that of the back-to-back feeding structures has a VSWR/spl les/2 from 2.2 to 18.6 GHz. This feeding structure can be used to feed a broadband planar leaky-wave antenna with a fixed mainbeam that uses the tapered microstrip structure. The measured bandwidth of the antenna for a VSWR/spl les/2 exceeds 2.3:1. 相似文献
83.
Quantitative assessment of estrogenic activity in the water environment of Korea by the E-SCREEN assay 总被引:2,自引:0,他引:2
In this study, the E-SCREEN assay was optimized and validated for the sensitive quantitative determination of the total estrogenicity in river samples. River water and sediment samples were collected and analyzed with the E-SCREEN. River water (10 l) was extracted using combined solid-phase extraction in static adsorption mode with Soxhlet extraction. Estrogenic pollutants adsorbed to the XAD-4 resin were recovered with 98.24 +/- 5.90% efficiency by elution with ethyl acetate and dichloromethane (1:9). The detection limit by 17beta-estradiol equivalent concentration (EEQ) of the E-SCREEN assay was 8.03 pg EEQ/l. Among the water samples, the estrogenic activity was observed to be higher downstream of the Kumho river (7.43 ng EEQ/l) and upstream of Kum river (2.05 ng EEQ/l) than in other samples. More than 3 mg of equivalent sediment samples from the Kumho river, Kum river and Miho stream showed partial agonistic effects, and the Mankyung river showed a partial agonistic effect with only 1.5 mg of sediment. The highest value of RPE was 83.34 downstream of the Kumho river, and the lowest value of RPE was 6.52 downstream of the Miho stream. Full estrogen agonistic activities were observed downstream of the Kumho river and upstream of the Kum river. The partial agonistic activity was observed in upstream of the Kumho river, downstream of the Mankyung river, and upstream of the Miho stream, and no agonistic action was observed downstream of the Kum river or Miho stream, or upstream of the Mankyung river. The total estrogenic activity in the river water and sediment samples was between 0.50 pg/L and 7.4 ng/L, 3.39 pg/g and 10.70 pg/g. 相似文献
84.
85.
We study the problem of dynamic pricing, promotion and replenishment for a deteriorating item subject to the supplier's trade credit and retailer's promotional effort. In this paper we adopt a price- and time-dependent demand function to model the finite time horizon inventory for deteriorating items. The objective of this paper is to determine the optimal retail price, the promotional effort and the replenishment quantity so that the net profit is maximized. We discuss the properties and develop an algorithm for solving the problem described. The numerical analyses show that an appropriate promotion policy can benefit the retailer and that the promotion policy is important, especially for deteriorating items. Furthermore dynamic decision-making is shown to be superior to fixed decision-making in terms of profit maximization. Some special cases, such as with no credit period and for non-deteriorating items, are discussed as is the influence of the time-varying demand, the rate of deterioration and the credit period on the retailer behavior. 相似文献
86.
Kuo-Shyang Jeng I-Shyan Sheen Shu-Sheng Lin Chuen-Miin Leu Chiung-Fang Chang 《International journal of molecular sciences》2021,22(6)
Endoglin (CD105) is a type-1 integral transmembrane glycoprotein and coreceptor for transforming growth factor-β (TGF-β) ligands. The endoglin/TGF-β signaling pathway regulates hemostasis, cell proliferation/migration, extracellular matrix (ECM) synthesis and angiogenesis. Angiogenesis contributes to early progression, invasion, postoperative recurrence, and metastasis in hepatocellular carcinoma (HCC), one of the most widespread malignancies globally. Endoglin is overexpressed in newly formed HCC microvessels. It increases microvessel density in cirrhotic and regenerative HCC nodules. In addition, circulating endoglin is present in HCC patients, suggesting potential for use as a diagnostic or prognostic factor. HCC angiogenesis is dynamic and endoglin expression varies by stage. TRC105 (carotuximab) is an antibody against endoglin, and three of its clinical trials were related to liver diseases. A partial response was achieved when combining TRC105 with sorafenib. Although antiangiogenic therapy still carries some risks, combination therapy with endoglin inhibitors or other targeted therapies holds promise. 相似文献
87.
Jih‐Hung Pan Yi‐Song Chen Lee‐Yen Sheen Been‐Huang Chiang 《Journal of the science of food and agriculture》2008,88(13):2223-2230
BACKGROUND: Submerged cultivation of Antrodia cinnamomea was carried out for manufacturing the fermentation product with anti‐hepatoma activity. The fermentation process was optimized for different parameters at shake flask level to obtain products with high inhibition potency against Hep G2 hepatoma cells. Scale‐up of the fermentation process was then achieved from 250 mL shake flask to 5 L, 500 L and 5‐ton fermenters. RESULTS: Glucose and malt extract were found to be the best carbon and nitrogen sources, respectively. The initial pH of 5.0 and an operating temperature of 22 °C were the best for a product with lowest IC50 value. A shorter cultivation time was required when the scale of fermentation increased from 5 L to 5 tons. The reducing sugar and solids contents of the broth filtrate were correlated exponentially with the IC50 of the ethanolic extract of mycelium for hepatoma cells, and the level of ergosterol in the mycelium extract follows the same profile as the increase in Hep G2 cells inhibition. CONCLUSION: When Antrodia cinnamomea is cultured in a 5‐ton fermenter, 4 weeks are required for the fermentation product to reach the highest anti‐hepatoma activity. The solid and reducing sugar contents of the broth filtrate as well as the ergosterol content in the ethanol extract of mycelium can serve as the marker during fermentation for manufacturing product with anti‐hepatoma activity. Copyright © 2008 Society of Chemical Industry 相似文献
88.
Yi-Chung Fu Binghuei B. Yang Chung-Jen Chen & Shiow-Shuh Sheen 《International Journal of Food Science & Technology》2005,40(7):743-757
A simple minimally perturbing method and an apparatus for on‐line measuring the electric field ( E ‐field) intensity at a particular small region, or a localized point in an electromagnetic field is described. The theoretical considerations and methodology for on‐line measuring electric field intensity are presented. They are based on measurement of the differential heating of the temperature rise using a fiberoptic temperature sensor at which a selected droplet of dielectric medium is dissipated in an electromagnetic field. The performance of the apparatus was examined and verified from power dissipation calculations of the water load. There was good agreement between the experimental and predicted value of average water temperature based on electric field on‐line measurement. 相似文献
89.
Jyh Sheen Chueh-Yu Li Liang-Wen Ji Wei-Lung Mao Weihsing Liu Chin-An Chen 《Journal of Materials Science: Materials in Electronics》2010,21(8):817-821
This research provides a simple method to measure the dielectric properties of thin films at microwave frequencies. The cavity
perturbation theory is applied to the measurement method. The measured frequency is in X-band (8.2–12.4 GHz). The titanium
dioxide thin films are deposited by the RF reactive magnetron sputtering method onto borosilicate glass substrates. The microwave
complex permittivity of films is then measured by the extended cavity perturbation technique. It was found the dielectric
constants of titanium dioxide thin films strongly depend on the partial pressure of oxygen. The dielectric constant maximized
at a value of 95 with 30% O2. This is the first report that confirms the high dielectric constant of TiO2 thin films at microwave frequencies which shows its potential for high-K related microwave devices. 相似文献
90.
CALUX, Chemically Activated LUciferase gene eXpression bioassay, has proven valuable for screening for and assessing toxic equivalents of dioxin-like compounds, because it detects all AhR (arylhydrocarbon receptor) ligands in a variety of sample matrices. In this study, we tried to validate DRE (dioxin-response elements)-CALUX bioassay, which has been developed by cloning mouse cyp1a1 gene in front of luciferase reporter gene. We compared DRE-CALUX bioassay with high resolution gas chromatography/mass spectrometry (HRGC/MS) for assessing environmental samples from Korea. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) dose response study showed high correlation (r2=0.89) between DRE-CALUX bioassay and EROD (ethoxyresorufin O-deethylase) bioassay, a commonly used bioassay method. The mean TEQ value of water samples was 0.57 pg-TEQ(HRGC/MS)/L and 4.97 pg-TEQ(CALUX)/L. For soil samples, HRGC/MS-TEQ values ranged from 0 to 47.18 pg-TEQ/g (dry) and correlated well (r2=0.98) with values obtained by CALUX-TEQ which ranged from 0.92 to 649.97 pg-TEQ/g (dry). The difference between the absolute TEQ values might be due to the presence of dioxin-like compounds without WHO-TEQ values rather than the difference between CALUX-REP and WHO-TEQ. Based on this study, we suggest that DRE-CALUX bioassay can serve as an alternative bioassay method for high-throughput analysis of large number of environmental samples. 相似文献