Attitude determination, along with attitude control, is critical to functioning of every space mission. In this paper, we investigate and compare, through simulation, the application of two autonomous sequential attitude estimation algorithms, adopted from the literature, for attitude determination using attitude sensors (sun sensor and horizon sensors) and rate-integrating gyros. The two algor...

Attitude Determination System (ADS) is a process to determine the attitude of a satellite by using on board sensors and attitude estimation algorithms to determine the orientation of the satellite which is relative to inertial reference frame such as Earth reference frame. The ADS is consists of an attitude sensor which provides the attitude and orbital position of the satellite to the Attitude...

Implicit in many informal and formal principles of psychological change is the understudied assumption that change requires either an active approach or an inactive approach. This issue was systematically investigated by comparing the effects of general action goals and general inaction goals on attitude change. As prior attitudes facilitate preparation for an upcoming persuasive message, gener...

A prominent defence of a market in organs from living donors says that if we truly care about people in poverty, we should allow them to sell their organs. The argument is that if poor vendors would have voluntarily decided to sell their organs in a free market, then prohibiting them from selling makes them even worse off, at least from their own perspective, and that it would be unconscionably...

Most smokers become addicted to tobacco products before they are legally able to purchase these products. We systematically reviewed the literature on protocols to assess underage purchase and their ecological validity. We conducted a systematic search in May 2015 in PubMed and PsycINFO. We independently screened records for inclusion. We conducted a narrative review and examined implications o...

BACKGROUND Texas does not require health education or tobacco use prevention education (TUPE) in its middle schools. During planning for the Texas Tobacco Prevention Initiative, this baseline research was conducted to (1) describe tobacco prevention and control practices in middle schools prior to the pilot, (2) analyze implementation of a state law prohibiting tobacco use on campuses and at sc...

OBJECTIVE Radon and cigarette smoking have synergistic effects on lung cancer, even when radon concentrations are relatively low. Working through an electric utility company, we sought to reach smoking households with low radon concentrations and motivate smoking cessation or prohibiting smoking in the home. DESIGN Eligible homes (n = 714) were randomised to receive: (1) the Environmental Pro...

BACKGROUND The Synar Amendment was enacted by the US Congress in 1992 to require states and territories to establish and enforce laws prohibiting the sale of tobacco to minors. OBJECTIVE To describe state and federal efforts to comply with the Synar mandate. METHODS State and federal actions were examined for the eight years following enactment. DATA SOURCES Federal documents from 1992-20...

BACKGROUND In October, 2008, legislation was implemented in the city and county of San Francisco, California, prohibiting the sale of tobacco products in pharmacies. OBJECTIVE To characterise public awareness and perceptions of the ban on tobacco sales in San Francisco community pharmacies. METHODS A brief, anonymous survey was used to assess public awareness and perceptions of a ban on tob...

Many critics have suggested that international paid surrogacy is exploitative. Taking such concerns as its starting point, this article asks: (1) how defensible is the claim that international paid surrogacy is exploitative and what could be done to make it less exploitative? (2) In the light of the answer to (1), how strong is the case for prohibiting it? Exploitation could in principle be dea...