What is exfiltration and infiltration? Air infiltration is the movement of air into a building, whereas air exfiltration is the movement of air out of a building. Air flows into or out of a building because of pressure differences between the internal and external environments of the building.
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Air infiltration is the movement of air into a building, whereas air exfiltration is the movement of air out of a building. Air leakage into building interiors has a considerable impact on the energy demand of the building (see figure 1).
This data exfiltration method is a common form of accidental insider threat. The malicious actor accesses sensitive corporate information on their trusted device, then transfers the data onto an insecure device.
The act or process of infiltrating, as of water into a porous substance, or of a fluid into the cells of an organ or part of the body. The substance which has entered the pores or cavities of a body. The act of entering a physical location and/or organization secretly.
This model yields cumulative infiltration and the infiltration rate as an implicit function of time (i.e., given a value of time (t), values of the cumulative infiltration (I) and the infiltration rate (q) can be directly obtained. Thus, the model functions are q (t) and I (t), rather than of t (q) and t (I).)
Air infiltration and exfiltration in buildings is controlled by an air barrier system. This system includes interconnected materials, flexible sealed joints and building envelope components that create an airtight enclosure. In addition, the air barrier system will also separate conditioned and unconditioned spaces.
Materials suchs as fiberboard, perlite board or uncoated concrete blocks should not be used because air passes through them easily.
Diffuse flow: occurs when the envelope materials are ineffective in controlling flow. For example the building foundation may be porous. Diffuse flow occurs when the materials has cracks, holes, or they have a high permeability to air. Permeability is the ability of a material to allow liquids and gases to pass through it. Materials with a high permeability to air include fibrous insulation or uncoated concrete blocks. This is the yellow arrow in figure 2.
This means that controlling how air moves into and out of buildings is a big part of hose energy efficiency can be improved for buildings. Energy, typically in the form of heat, must be added to or removed from a building in order to maintain a comfortable interior climate for the occupants. Heating, ventilation and air conditioning ( HVAC) systems are used to add or remove heat from a building interior and the operation of these systems costs money. Consequently, air infiltration and exfiltration will impact a building’s energy costs. Infiltration also affects indoor air quality because it introduces pollutants, allergens, and microbes into the building. It can also result in moisture accumulation in the building envelope because airflow carries with it rainwater and water vapor (see moisture intrusion ). Of course all buildings must have sufficient ventilation to be comfortable as well, which is why air infiltration and exfiltration must be handled properly.
Differences in air pressure between the interior and exterior of a building will cause infiltration and exfiltration, see figure 3. These pressures include:
Air flows into or out of a building because of pressure differences between the internal and external environments of the building. These pressure differences can be caused by gusting winds or differences in internal and external temperatures. The air will flow through the various openings in the building envelope. These vary from from large openings such as doors and windows, to small cracks and crevices caused by improper installation of envelope components.
Stack pressure: sometimes called chimney effect or buoyancy, stack pressure is caused by a difference in atmospheric pressure at the top and bottom of a building due to differences in height and temperature.
If the assessment of the involved extremity is inconclusive, the application of pressure on the vein, about two inches above the insertion site (and above the tip of the cannula) with a finger or tourniquet, will decrease or stop the flow of fluid if the cannula is still in the vein. If an infiltration is present, the rate will remain unchanged. If the infusion continues despite the obstruction applied, an infiltration has occurred.
Check your institution’s policy regarding which type of compress (warm or cold) should be applied. Generally speaking, if the infiltration solution was isotonic, a warm compress is used to alleviate discomfort and help absorb the infiltration by increasing circulation to the affected area.
Extravasation can result in tissue sloughing, pain, loss of mobility in the extremity and infection. The treatment for extravasation will vary depending on the antidote for the infiltrated medication and your facility policy.
IV infiltration is one of the most common problems that can occur when fluid infuses into the tissues surrounding the venipuncture site. This sometimes happens when the tip of the catheter slips out of the vein, ...
This sometimes happens when the tip of the catheter slips out of the vein, the catheter passes through the wall of the vein, or the blood vessel wall allows part of the fluid to infuse into the surrounding tissue.
In certain situations, a cold compress is recommended. An extravasation occurs when there is accidental infiltration of a vesicant or chemotherapeutic drug into the surrounding IV site. Vesicants can cause tissue destruction and / or blistering. Irritants can result in pain at the IV site and along the vein and may or may not cause inflammation. ...
Inflow and infiltration is defined as groundwater and stormwater that enter a sewer system. Collection systems can be damaged when they are forced to transport more flow than they are designed to handle. Increased effluent also raises costs for wastewater treatment facilities, because harmless stormwater and groundwater mix with sewage. In many cases, inflow and infiltration (I&I) accounts for up to 45% of the annual flow to treatment plants.
Infiltration occurs when groundwater seeps into sewer pipes through cracks, leaky pipe joints and/or deteriorated manholes.
The financial impact of inflow and infiltration includes both treatment costs and regulatory penalties.
Inflow and infiltration robs valuable capacity from treatment plants. Such capacity shortfalls can lead to damaging and costly sanitary sewer overflows (SSOs). Thirty-five percent of water entering a water treatment plant is I&I, according to the Chalmers University of Technology’s Division of Water Environment Technology. Another 35% is stormwater, and the remaining 30% is sewage. In other words, 70% of total flow into a treatment facility is water that would not need treatment had it not entered a sewer line.
Exfiltration is defined as the leakage of wastewater out of a sanitary sewer system. Exfiltration seeps out of broken or damaged pipes and manholes. Wastewater that leaks from defective pipe joints and cracks may contaminate ground and surface water and nearby water bodies.
Groundwater seeps into sewer pipes through cracks, leaky pipe joints and deteriorated pipes. A CCTV inspection is the most thorough way to find and understand I&I in pipelines. Sewer inspection crawlers use a video camera mounted on a remote-controlled robotic crawler that is connected to a monitor. An operator watching the video can stop to study parts of the pipe to find the specific location and cause of infiltration.
Exceeding the capacity of the collection system can result in discharge of untreated wastewater into the environment. This discharge may come from collection system components or from a treatment system that doesn’t have the capacity to treat the water. Infiltration can also cause pipe structure failures due to erosion of soil support, and ground subsidence due to erosion of underground soil.
is that exfiltration is (military) the process of exiting an area (usually behind enemy lines or in enemy territory) while infiltration is the act or process of infiltrating, as of water into a porous substance, or of a fluid into the cells of an organ or part of the body.
The act or process of infiltrating, as of water into a porous substance, or of a fluid into the cells of an organ or part of the body.
The vertical movement of water in the soil profile from the surface to water table is a dynamic condition. It can be conceptualized as being composed of basically two predominant processes: infiltration and exfiltration. Exfiltration can be envisioned as the processes dominating during drying periods; water released during this period can be thought of as being released through evaporation to the atmosphere. The model (INFEXF) selected for this project is a formulation of the Philips model developed by Eagleson (1978) to account for water infiltration during the wetting season and exfiltration during the drying season. Infiltration and exfiltration as described in this application assumes the soil medium to be effectively semi-infinite and the internal soil water content at the beginning of each storm event and inter-storm period is assumed to be uniform at its long-term and space-time average. The exfiltration equation is modified for the presence of natural vegetation through the approximate introduction of a distributed sink representing the moisture extraction by plant roots. Two scenarios are presented in the accompanying worksheet applications: water infiltration during the rainy season and water exfiltration during the drying season. Infiltration/Exfiltration MathCad Code (ZIP) (4 K)
The initial Green Ampt model was the first physically based model/equation describing the infiltration of water into soil. It has been the subject of considerable development in soil physics and hydrology, owing to its simplicity and satisfactory performance for a great variety of water infiltration problems. This model yields cumulative infiltration and the infiltration rate as an implicit function of time (i.e., given a value of time (t), values of the cumulative infiltration (I) and the infiltration rate (q) can be directly obtained. Thus, the model functions are q (t) and I (t), rather than of t (q) and t (I).) The Explicit Green-Ampt model as defined and used for this project's application was developed by Salvucci and Entekhabi (1994). The application provides a straightforward and accurate estimation of infiltration for any given time. This formulation supposedly yields an error of less than 2 percent at all times when compared to the exact values resulting from the Implicit Green Ampt model. Explicit Green Ampt MathCad Code (ZIP) (4 K)
The SCS model is an empirically developed approach to the water infiltration process (Jury, et al. 1991). It has been developed by first finding a mathematical function whose shape as a function of time matches the observed features of the infiltration rate. This function is then provided a physical explanation of the process. In semi-empirical models, most physical processes are represented by commonly accepted and simplistic conceptual methods rather than by equations derived from fundamentally physical principles. The commonly used semi-empirical infiltration model in the fields of soil physics and hydrology is the SCS model. A scenario was chosen to simulate water infiltration into a soil for conditions with rainfall and surface runoff by using the SCS model. Input parameters and simulation results are discussed in Estimation of Infiltration Rate in the Vadose Zone: Compilation of Simple Mathematical Models, Volume II . SCS MathCad Code (ZIP) (2 K)
The Philip's Two-Term model (PHILIP2T) is a truncated power series solution developed by Philips (1957). During the initial stages of infiltration (when t is very small), the first term of the model/equation dominates the process. In this stage, the vertical infiltration proceeds at almost the same rate as absorption or horizontal infiltration. In this stage of infiltration, the gravity component, represented by the second term of the model/equation, is negligible. As infiltration continues, the second term becomes progressively more important until it dominates the infiltration process. Philips (1957) suggested the use of the two-term model in applied hydrology when t is not too large. A scenario was chosen to simulate the water infiltration into a sandy soil by using the PHILIP2T model. Input parameters and simulation results are discussed in Estimation of Infiltration Rate in the Vadose Zone: Compilation of Simple Mathematical Models, Volume II. Philip's Two-Term MathCad Code (ZIP) (4 K)
In semi-empirical models, most physical processes are represented by commonly accepted and simplistic conceptual methods rather than by equations derived from fundamentally physical principles. The commonly used semi-empirical infiltration model in the fields of soil physics and hydrology is the SCS model.
Phenomena of Water Infiltration in the Unsaturated Zone. Water applied to the soil surface through rainfall and irrigation events subsequently enters the soil through the process of infiltration. If the supply rate of water to the soil surface is greater than the soil's ability to allow the water to enter, excess water will either accumulate on ...
Wetting Front – This zone is characterized by a steep hydraulic gradient and forms a sharp boundary between the wet and dry soil. The hydraulic gradient is characterized primarily by metric potentials.
A common data exfiltration definition is the theft or unauthorized removal or movement of any data from a device. Data exfiltration typically involves a cyber criminal stealing data from personal or corporate devices, such as computers and mobile phones, through various cyberattack methods.
Other types of malware will lay dormant on a network to avoid detection by organizations’ security systems until data is exfiltrated subversively or information is gradually collected over a period of time.
These include anonymizing connections to servers, Domain Name System (DNS), Hypertext Transfer Protocol (HTTP), and Hypertext Transfer Protocol Secure (HTTPS) tunneling, direct Internet Protocol (IP) addresses, fileless attacks, and remote code execution.
The cloud provides users and businesses with a multitude of benefits, but along with it are significant data exfiltration risks. For example, when an authorized user accesses cloud services in an insecure manner, they enable a bad actor to make changes to virtual machines, deploy and install malicious code, and submit malicious requests to cloud services. Human error and procedural issues also play a role in data exfiltration, as the appropriate protection may no longer be in place.
Social engineering and phishing attacks are a popular network attack vector used to trick victims into downloading malware and giving up their account credentials.
Data exfiltration occurs in two ways, through outsider attacks and via insider threats. Both are major risks, and organizations must ensure their data is protected by detecting and preventing data exfiltration at all times.
Cyber criminals use email to exfiltrate any data that sits on organizations’ outbound email systems, such as calendars, databases, images, and planning documents. This data can be stolen from email systems as email and text messages or through file attachments.