Noise (AWGN) Avoidance in CDMA Systems Using the Mechanism of Spread Spectrum

In today communication systems the most probable problems are that of channel capacity, jamming and interference or noise. The channel capacity can be maximized by multiplexing the channel. While the jamming problem and for noise reduction the most important technique that we can apply is spread spectrum. That by spreading the spectrum of the original message signal, the impact of noise upon the message signal can be reduced. For that purpose, two different techniques that is DSSS(Direct Sequence Spread Spectrum) and FHSS (Frequency Hoping Spread Spectrum) can be applied. Since the two approaches are core ideas upon which CDMA system is based, so in this paper we have analyzed both the techniques to observe that h up to what extent they are efficacious in removing AWGN in CDMA systems communication. IndexTerms:DSSS, FHSS, Code Division Multiple Access (CDMA), Additive White Gaussian Noise (AWGN), spread spectrum

Feeling old on Facebook: an autoethnographic analysis of ageism among younger people towards their peers

Population aging and the proliferation of numerous social networking sites such as Facebook (FB) have necessitated different approaches to investigating age-based discrimination called ageism. Although the current evidence provided information on younger adults’ attitudes towards older adults, little is known about the younger individuals’ attitudes towards their peers in a digital sphere. This autoethnographic study, conducted in November 2020, aimed at understanding younger FB user’s (n = 37) attitudes towards their peers, and the manifestation of plausible digital facets of ageism. I posted a public status using a specific FB feature called feeling old on my FB Wall and analyzed the comments (both emoticons and textual) by others in relation to the post/status. The study is guided by the theoretical lens of symbolic and interpretive anthropology. Results showed (a) younger FB users have age stereotyped negative attitudes towards their peers considering the FB status, and (b) emoticons used in comments expressed more negative attitudes towards old age compared to the textual comments. Both findings indicated potential connection to an internalized sense of ‘young’ and ‘old’ that embedded in socially grounded age stereotypes. Future and more research on digital platforms can be carried out targeting younger adults’ attitudes towards their own age group in order to understand the risk of emergence of ‘digital ageism’

Integration of surfactants and time release nutrients with pneumatic fracturing process

The objective of this laboratory study was the development of two novel improvements to the pneumatic fracturing process which would extend its present application. The first involved use of surfactant during pneumatic injection, and the second was subsurface injection of time-release dry nutrient pellets for enhancement of in situ biodegradation. Bench scale tests demonstrated that pneumatic fracturing can be successfully performed with air containing a surfactant solution (foam fracturing). The results showed that foam fracturing followed by increased the rate of surrogate contaminant removal from 8% to 10% compared with regular pneumatic fracturing. These increases were attributed to enlarged fracture networks and increased airflow. Commercially available anionic surfactants, which are biodegradable, were used for the process. Recommendations for field scale applications were also developed. It was also shown that injection of time release nutrient pellets into subsoil during pneumatic fracturing is feasible. Bench scale equipment for this process was developed and tested. Mechanical damage of the nutrient pellets during pneumatic injection was evaluated by different methods, and it was determined that serious damage was sustained above 75 psi. These results suggest pellets with higher mechanical strength characteristics are necessary for successful field integration with pneumatic fracturing process

COVID-19:A case report from Bangladesh perspective

A 34-year-old man without any significant medical history or comorbidities, suddenly developed fever, and shortness of breath, thereby admitted to the emergency department of a tertiary care hospital, Dhaka, Bangladesh. He had neither a history of traveling to Coronavirus disease (COVID) prone areas nor a direct contact of COVID positive patients. His chest X-ray revealed ground-glass opacity in the right middle and lower zone of the lung. The first polymerase chain reaction (PCR) test on throat and nasal swabs for the COVID upon admission was negative. Based on the chest X-ray result, RT-PCR was done again resulted positive. The patient was primarily treated with chloroquine and azithromycin. On full recovery, he was discharged from the hospital on day 12, after two subsequent throat swab samples tested negative by PCR (24 hours apart). He was encouraged to maintain home quarantine for at least the next 14 days. SARS-CoV-2 RNA by swab remained negative and the blood sample shows the presence of antibody (both IgM and IgG) in his follow-up visit (after 7 days of hospital discharge).</p

Occupational Health and Safety (OHAS) crisis in tanneries of Bangladesh: Is this the violation of labor rights?

Tannery business in Bangladesh is one of the oldest manufacturing sub-sectors and it has huge growth potential. It has been remained profitable venture since its inception. However, this sector has got adverse affect both in human life and environment. Employees who work for tanneries face severe health hazards and people live in neighborhood are also affected by environmental pollutions. Toxic exposure of chemicals in tanneries of Bangladesh violates health and safety compliances. Both workers and neighborhood people of tanneries suffer from gastrointestinal, respiratory, jaundice, hypertension and skin diseases due to inefficient and improper waste management system. Tanneries in Bangladesh have failed to maintain Occupational Health and Safety (OHAS) which is also the violation of labor right. This may lead to labor unrest in near future like RMG sector in Bangladesh. This study explores the current health and safety practices at tanneries in Bangladesh. Health problems and challenges of tannery workers are also reported in this research, and some recommendations are made at the end as possible remedy. Key Words: Tannery, Occupational Health and Safety (OHAS), Labor Right &amp; Unrest