IMPORTANT NOTE REGARDING WORD LIMIT REQUIREMENTS:

Please note that each and every assignment has its own word limit.

Causation is the portion of epidemiology that identifies the causes of diseases and association is the observation of the association on the effect of the disease. There are four types of a causal relationship, they are necessary and sufficient, necessary but not sufficient, sufficient but not necessary, and neither sufficient nor necessary. Necessary and sufficient is when both factors will lead to the development of the diseases, but without the necessary factor, the development of the diseases will never occur, but with the sufficient factor, the diseases will always occur. An example of necessary and sufficient is the situation where a person who had chickenpox due to the varicella-zoster virus is at risk of getting the shingles virus, but not everyone who had the chickenpox will activate the shingles virus (Celentano& Szklo, 2019).

Necessary but not sufficient is when the condition is necessary but not sufficient to cause the disease. For example, someone getting the influenza shot, but not getting enough to produce the disease because of the strong immune system, whereas, some people with the weak immune systems getting the same dosage of the flu shot, which resulted in producing the disease. Sufficient but not necessary is when each factor alone can produce the disease, along with other cofactors. For example, factors such as drinking, smoking or obesity can cause diabetes, but some people do not develop diabetes from either, but other cofactors paired with a factor can produce diabetes. Neither sufficient nor necessary is when neither factors by itself can produce the disease, it needs other factors. For example, an individual can develop cardiovascular diseases if they are exposed to high blood pressure, diabetes, obesity, drinking, and smoking. However, each risk factors are neither sufficient or necessary, but if they are paired like diabetes and drinking, or smoking and obesity, or high blood pressure and diabetes, then they can produce a disease (Celentano& Szklo, 2019).

There are nine casual guidelines that depicts whether an observed association is causal. They are temporal relationship, the strength of the association, dose-response relationship, replication of the finding, biologic plausibility, consideration of alternate explanations, cessation of exposer, consistency with other knowledge, and specificity of association. The one I think is most difficult to establish is biological plausibility. This is because it requires an in-depth observation of the body depending on the subject of the research. These observations can have a long duration meaning the body they are observing and experimenting on can die before the result is achieved. Additionally, biological plausibility depends on the interpretation of existing knowledge. These interpretations use high-tech medical technology, such as screening assays to identify toxic agents and etc. However, using past data and comparing it to existing knowledge can cause interpretation issues depending on the time frame of the past data (Celentano& Szklo, 2019; Fedak et al., 2015).

Reference

Celentano, D. D., & Szklo, M. (2019). Gordis epidemiology (6th ed.). Philadelphia, PA: Elsevier. ISBN-13: 9780323552295

Research/summary of industry trends – You must conduct research on what the industry trends (internationally) are for the hospitality industry. These trends MUST include these areas: salary/benefits, availability of jobs/location of the jobs/employment trends, and experience/education needed. The trends must cover at least a one-year period and must be current trends. Submitting trends that were published three years ago is not going to assist you. Research must be properly cited using APA 7th edition guidelines (inclusive of a reference page) or NO credit will be given.

Ch 10 Advanced Development

Ch 12 Engineering Design

Please answer one of the question on the file attached below:

choose only 1 question from the file attached

I want a replay for the discussion post below .

(((( 6 type of external interfaces that will require critical attention in subway

1-Air monitoring and ventilation

The confined space occupied by the underground subway system can accumulate the pollutants entering from the outside in addition to those generated within the system. Therefore, it is likely that the subway system in an area contains different types of hazardous pollutants. All underground installation is classified as gassy and requires enough ventilation to prevent accumulation of gases to an explosion level. Normal ventilation fans shall, even be designed for continuous operation

2- flood control

In principle, there are many ways of mitigating flood risk in subway to reduce or avoid possible impact of flooding, such as building levees and tidal barriers. Several measures apply directly to underground transport systems. For example, cities can install backup power for pump systems to reduce or avoid the potential for infrastructure damage when power outages occur, and clear flooded tunnels more quickly. Similarly, flood gates and raised entrances at stations could allow the underground transport system to continue operations even during floods. Or by new technology includes subway “plugs”, which look and work like big balloons. They can inflate in just a few minutes to help prevent water from entering underground tunnels. When not in use, the plug packs down to a small storage space in the tunnel, ready for remote, immediate inflation in an emergency. But for all this useful engineering, we do have to realize that there is no feasible way to provide total flood prevention and there will always be some risk of flooding. That means we need to become more resilient to flooding when it does occur through prevention, preparation and planning.

3- Emergency protective, including evacuation plan

In Subway construction we should be consider an area called a( safe stations ), in case of any emergency detected ,one of these stations will be the safest place in the subway .( mentioned in exercise English France tunnel)

4- fire prevention and protection

Underground passenger station should be equipped with a fare collection system and a fare collection control system. Local station control and monitoring shall be at the station fare collection control unit, and remote monitoring/ patron registering shall be by a data transmission interface cabinet

5- Illumination

by providing an atmosphere of relative comfort, pleasantness and cleanliness of surroundings, and a sense of personal safety and security. Lighting for passenger stations should be bright and cheerful, so all artwork illumination shall be approved by the architect.

6- The ground settlement during subway station construction in populous city areas is the most important factor that needs to be controlled ))))))

Use this book only and i have the power point lecture recorded let me know if you need it.

A. Kossiakoff W. Sweet, S. Seymour, and S. Biemer. Systems Engineering Principles and Practice, Second Edition, Wiley, 2011. ISBN: 978-0-470-40548-2

Please note i want answer to the question and i want a replay to the discussion post between parenthesis above

separate the answer and the replay from each other .