High Speed Packet Access Broadband Mobile Communications

2009 ◽  
pp. 595-604
Author(s):  
Athanassios C. Iossifides ◽  
Spiros Louvros
Keyword(s):  
Mobile Communications ◽  
Rural Areas ◽  
High Speed ◽  
Data Transfer ◽  
Mobile Wimax ◽  
Major Step ◽  
Transfer Rates ◽  
Mobile Broadband ◽  
History Of ◽  
Broadband Market

Mobile broadband communications systems have already become a fact during the last few years. The evolution of 3G Universal Mobile Telecommunications Systems (UMTS) towards HSDPA/HSUPA systems have already posed a forceful solution for mobile broadband and multimedia services in the market, making a major step ahead of the main competitive technology, that is, WiMax systems based on IEEE 802.16 standard. According to the latest analyses (GSM Association, 2007; Little, 2007), while WiMax has gained considerable attention the last few years, HSPA is expected to dominate the mobile broadband market. The main reasons behind this forecast are: • HSPA is already active in a significant number of operators and is going to be established for the majority of mobile broadband networks worldwide over the next five years, while commercial WiMax systems are only making their first steps. • Mobile WiMax is a competitive technology for selection by operators in only a limited number of circumstances where conditions are favourable. Future mobile WiMax systems may potentially achieve higher data transfer rates than HSPA, though cell coverage for these rates is expected to be substantially smaller. In addition, WiMax technology is less capable in terms of voice traffic capacity, thus limiting market size and corresponding revenues. • In order to overcome the aforementioned disadvantages, WiMax commercial launches are expected to introduce a relative CAPEX disadvantage of at least 20–50% comparing to HSPA, in favorable cases, while there are indications of an increase by up to 5–10 times when accounting for rural areas deployments. The short commercial history of HSDPA (based on Rel.5 specifications of 3GPP) started in December of 2005 (first wide scale launch by Cingular Wireless, closely followed by Manx Telecom and Telekom Austria). Bite Lietuva (Lithuania) was the first operator that launched 3.6 Mbps. HSUPA was first demonstrated by Mobilkom Austria in November 2006 and soon launched commercially in Italia by 3 in December 2006. Mobilkom Austria launched the combination of HSDPA at 7.2 Mbps and HSUPA in February 2007. By September of 2007, less than two years after the first commercial launch, 141 operators in 65 countries (24 out of 27 in EU) have already gone commercial with HSDPA with 38 operators among them supporting a 3.6 Mbps downlink. In addition, devices supporting HSDPA/HSUPA services are rapidly enriched. 311 devices from 79 suppliers have already been available by September 2007, including handsets, data cards, USB modems, notebooks, wireless routers, and embedded modules (http://hspa.gsmworld.com).

scholarly journals Smart Health Monitoring System for Pregnant Women

2020 ◽  
Vol 9 (4) ◽  
pp. 923-926
Keyword(s):  
Blood Pressure ◽  
Blood Glucose ◽  
Blood Glucose Level ◽  
Pregnant Women ◽  
Glucose Level ◽  
Health Monitoring ◽  
Rural Areas ◽  
High Speed ◽  
Data Transfer ◽  
Critical Issues

For pregnant ladies, various health parameters like ECG, blood pressure, SPO2 (stamina), respiration rate, blood glucose level, body temperature, etc. need to be monitored regularly and must be in a normal level. If the mother’ health become critical then definitely it will affect the baby. Hence it is recommended by physicians to do routine checkups at primary stages of pregnancy. But in rural areas, due to unavailability of well-equipped hospital facilities and also people don’t have awareness about their health which yields in abnormalities or creates critical issues. The presented paper summarizes, the available system and their strength and weakness and challenges in health monitoring of pregnant women. The proposed system is used to analyze various pregnancy biological factors like heart rate of pregnant women & Fetus, changes in blood pressure, blood glucose level, temperature, and weight. The proposed system will help for the rapid decision making and treatment through the high speed medical data transfer to the physicians over mobile for consulting and remote medical examinations. These values are transferred to database, to upload on server which can be monitored from any corner of the world.

Experimental Observations of the Microlayer in Vapor Bubble Growth on a Heated Solid

1983 ◽  
Vol 105 (3) ◽  
pp. 625-632 ◽  
Author(s):  
L. D. Koffman ◽  
M. S. Plesset
Keyword(s):  
High Speed ◽  
Time History ◽  
Laser Interferometry ◽  
Nucleate Boiling ◽  
Thickness Change ◽  
Transfer Rates ◽  
High Speed Cinematography ◽  
History Of ◽  
Microlayer Evaporation ◽  
Fringe Patterns

Experimental measurements of microlayer formation and of the time history of microlayer thickness change have been obtained for nucleate boiling of water and ethanol. These detailed measurements were obtained using laser interferometry combined with high-speed cinematography. The measurement technique is discussed in detail with emphasis on the difficulties encountered in interpretation of the fringe patterns. The measurements for water can be reasonably applied to the data of Gunther and Kreith, in which case it is concluded that microlayer evaporation alone cannot account for the increased heat transfer rates observed in highly subcooled nucleate boiling. It appears that microconvection must play at least an equal role.

Multiple phase transitions investigated by high-speed TEM

1990 ◽  
Vol 48 (4) ◽  
pp. 550-551
Author(s):  
Oleg Bostanjoglo ◽  
Peter Thomsen-Schmidt
Keyword(s):  
Phase Transitions ◽  
High Speed ◽  
Short Exposure ◽  
Semiconductor Film ◽  
Time Resolved ◽  
Short Exposure Time ◽  
Multiple Phase ◽  
Model Substance ◽  
History Of ◽  
Electron Image

Thin GexTe1-x (x = 0.15-0.8) were studied as a model substance of a composite semiconductor film, in addition being of interest for optical storage material. Two complementary modes of time-resolved TEM were used to trace the phase transitions, induced by an attached Q-switched (50 ns FWHM) and frequency doubled (532 nm) Nd:YAG laser. The laser radiation was focused onto the specimen within the TEM to a 20 μm spot (FWHM). Discrete intermediate states were visualized by short-exposure time doubleframe imaging /1,2/. The full history of a transformation was gained by tracking the electron image intensity with photomultiplier and storage oscilloscopes (space/time resolution 100 nm/3 ns) /3/. In order to avoid radiation damage by the probing electron beam to detector and specimen, the beam is pulsed in this continuous mode of time-resolved TEM,too.Short events ( <2 μs) are followed by illuminating with an extended single electron pulse (fig. 1c)

Keeping Military Discipline

2013 ◽  
pp. 311-329
Author(s):  
Stefan G. Chrissanthos
Keyword(s):  
Roman Empire ◽  
Major Step ◽  
Roman Army ◽  
Modern System ◽  
History Of ◽  
Military Discipline

This chapter offers a brief history of military discipline in ancient armies, and also investigates how and to what degree societies inflicted discipline on their soldiers, and how, in various ways, soldiers imposed discipline on themselves. Then, it addresses the evolution of military discipline from Greece until eventually something similar to a modern system developed in the early Roman Empire. The death of Alexander had precipitated almost fifty years of continuous warfare that ultimately resulted in the development of the Hellenistic monarchies. The Roman army represented something completely new in ancient Mediterranean warfare. It is observed that the Principate represented a major step in the evolution of ancient military discipline.

scholarly journals COVID-19 Vaccine Acceptance in Azuay Province, Ecuador: A Cross-Sectional Online Survey

Vaccines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 678
Author(s):  
Julio Jaramillo-Monge ◽  
Michael Obimpeh ◽  
Bernardo Vega ◽  
David Acurio ◽  
Annelies Boven ◽  
...  
Keyword(s):  
Rural Areas ◽  
Online Survey ◽  
Vaccination Campaign ◽  
Postgraduate Education ◽  
Effective Vaccine ◽  
Cross Sectional ◽  
Lower Education Level ◽  
Vaccination Acceptance ◽  
History Of ◽  
High Level

We investigated the COVID-19 vaccination acceptance level in Azuay province, Ecuador through an online survey from 12th to 26th February (before the start of the COVID-19 vaccination campaign in Ecuador). Overall, 1219 respondents participated in the survey. The mean age was 32 ± 13 years; 693 participants (57%) were female. In total, 1109 (91%) of the participants indicated they were willing to be vaccinated with a COVID-19 vaccine, if the vaccine is at least 95% effective; 835 (68.5%) if it is 90% effective and 493 (40.5%) if it is 70% effective; 676 (55.5%) participants indicated they feared side effects and 237 (19.4%) thought the vaccine was not effective. Older age, having had a postgraduate education, a history of a negative COVID-19 test, a high level of worry of contracting COVID-19, believing that COVID-19 infection can be prevented with a vaccine and understanding there is currently an effective vaccine against COVID-19 were associated with higher vaccination acceptance. A vaccination education campaign will be needed to increase the knowledge of Ecuadorians about the COVID-19 vaccine and to increase their trust in the vaccine. People with a lower education level and living in rural areas may need to be targeted during such a campaign.

scholarly journals Dual-shot dynamics and ultimate frequency of all-optical magnetic recording on GdFeCo

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Sicong Wang ◽  
Chen Wei ◽  
Yuanhua Feng ◽  
Hongkun Cao ◽  
Wenzhe Li ◽  
...  
Keyword(s):  
Magnetization Reversal ◽  
Energy Efficient ◽  
High Speed ◽  
Data Transfer ◽  
Laser Pulses ◽  
Time Resolved ◽  
All Optical ◽  
Fs Laser ◽  
High Speed Data ◽  
Natural Way

AbstractAlthough photonics presents the fastest and most energy-efficient method of data transfer, magnetism still offers the cheapest and most natural way to store data. The ultrafast and energy-efficient optical control of magnetism is presently a missing technological link that prevents us from reaching the next evolution in information processing. The discovery of all-optical magnetization reversal in GdFeCo with the help of 100 fs laser pulses has further aroused intense interest in this compelling problem. Although the applicability of this approach to high-speed data processing depends vitally on the maximum repetition rate of the switching, the latter remains virtually unknown. Here we experimentally unveil the ultimate frequency of repetitive all-optical magnetization reversal through time-resolved studies of the dual-shot magnetization dynamics in Gd27Fe63.87Co9.13. Varying the intensities of the shots and the shot-to-shot separation, we reveal the conditions for ultrafast writing and the fastest possible restoration of magnetic bits. It is shown that although magnetic writing launched by the first shot is completed after 100 ps, a reliable rewriting of the bit by the second shot requires separating the shots by at least 300 ps. Using two shots partially overlapping in space and minimally separated by 300 ps, we demonstrate an approach for GHz magnetic writing that can be scaled down to sizes below the diffraction limit.

scholarly journals Association between self-care agency and depression and anxiety in patients with diabetic retinopathy

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bo Zhang ◽  
Qin Wang ◽  
Xuancan Zhang ◽  
Li Jiang ◽  
Lezhi Li ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Rural Areas ◽  
Self Care ◽  
Depression Scale ◽  
Anxiety Symptoms ◽  
Depression And Anxiety ◽  
Clinical Factors ◽  
Cross Sectional ◽  
History Of ◽  
Care Agency

Abstract Background This study aimed at investigating: 1) the relationship between self-care agency and depression and anxiety; 2) the sociodemographic and clinical factors associated with depression and anxiety in patients with diabetic retinopathy (DR) in China. Methods A cross-sectional study was conducted. One-hundred and five patients with DR were recruited. Self-care agency was assessed by the exercise of self-care agency (ESCA) scale. Depression and anxiety were assessed by the hospital anxiety and depression scale (HADS-D and HADS-A). Pearson or Spearman correlations were performed to assess the association between self-care agency and depression and anxiety. Stepwise multivariate linear regression analyses were conducted to assess the contribution of the sociodemographic and clinical factors to depression and anxiety. Results Thirty-six (34.3%) and 43 (41.1%) patients exhibited depressive and anxiety symptoms, respectively. Only 24 (22.9%) patients showed a high self-care agency. The ESCA total and subscale scores were negatively correlated depressive symptoms (P < 0.05). Self-care skills were negatively correlated with anxiety symptoms (P < 0.05). ESCA total score, rural residence, history of hypertension and visual acuity were associated with depression; self-care skills and diastolic blood pressure were associated with anxiety. Conclusions Self-care agency negatively correlates with depression and anxiety in patients with DR. Special attention should be paid to patients living in rural areas and/or those having a history of hypertension when assessing depression and anxiety in patients with DR. Future studies are needed to clarify the causal relationship between self-care agency and depression and anxiety.

Sign in / Sign up

Export Citation Format

Share Document