At first appearence the psychrometric chart is quiteconfusing, however with some practice it becomes an extremely usefultool for rapidly evaluating air-conditioning processes. The mostpopular chart in common usage is that developed by ASHRAE(American Society of Heating, Refrigeration andAir-Conditioning Engineers), however we feel that the construction ofa simplified version of the chart based on approximations of thevarious equations can be a very useful tool for developing anunderstanding of it's usage. This approach was suggested by MagedEl-Shaarawi in his article "On thePsychrometric Chart" published in the ASHRAE Transactions (Paper#3736, Vol 100, Part 1, 1994) and inspired us to produce thefollowing simplified psychrometric chart:
The basic information used to construct the chart isthe water vapor saturation data (Tsat, Pg) which is obtained fromsteam tables over the range from Tsat = 0.01C through 50C. Thespecific humidity ω is then evaluated using the relative humidity φas a parameter to produce the various relative humidity curves (bluelines) as follows:
Gm Bagi Bagi Char 11
Download File: https://cinurl.com/2vImZF
The major simplifying assumption in the constructionof the chart is that the enthalpy of the mixture is assumed to beconstant throughout the adiabatic saturation process (described inSectiona). This implies that the evaporatingliquid added does not significantly affect the enthalpy of theair-vapor mixture, leading to the constant slope wet bulb temperature/ enthalpy (red)lines defined by:
The four equations highlighted above were programmedin MATLAB and used to plot the simplified psychrometric charts shownabove. Refer to the link: MATLABprogram for plotting a Simplified Psychrometric Chart
An excellent NebGuide (University of Nebraska-LincolnExtension Publication) describing Howto use a Simplified Psychrometric Chart hasbeen provided by David Shelton and Gerald Bodman. Another usefulguide provided by Mark Cartwright of the North Carolina ContractorTesting Institute (NCCTI) is the YouTube video: PsychrometricChart Simplified. Both guides reduce theconfusion by separately explaining 4 of the 6 sets of curves whichmake up a psychrometric chart. Definitely review both guides beforecontinuing.
Solved Problem 10.1 - Assumethat the outside air temperature is 32C with a relative humidity φ= 60%. Use the psychrometric chart to determine the specific humidityω [18 gm-moisture/kg-air],the enthalpy h [78kJ/kg-air], the wet-bulb temperature Twb[25.5C],the dew-point temperature Tdp[23C],and the specific volume of the dry air v [0.89m3/kg].Indicate all the values determined on the chart.
Solved Problem 10.2: Assumethat the outside air temperature is 8C. If the air in a room is at25C with a relative humidity φ = 40%, use the psychrometric chartto determine if the windows of that room which are in contact withthe outside will become foggy.
One of the major applications of the PsychrometricChart is in air conditioning, and we find that most humans feelcomfortable when the temperature is between 22C and 27C, and therelative humidity φ between 40% and 60%. This defines the "comfortzone" which is portrayed on the Psychrometric Chart as shownbelow. Thus with the aid of the chart we either heat or cool, addmoisture or dehumidify as required in order to bring the air into thecomfort zone.
Solved Problem 10.4:: Hotdry air at 40C and 10% relative humidity passes through anevaporative cooler. Water is added as the air passes through a seriesof wicks and the mixture exits at 27C. Using the psychrometricchart determine (a) the outlet relative humidity [45%],(b) the amount of water added [5.4g-H20/kg-dry-air],and (c) the lowest temperature that could be realized [18.5C].
A garde manger (pronounced [gaʁd mɑ̃ʒe]; French) is a cool, well-ventilated area where cold dishes (such as salads, hors d'œuvres, appetizers, canapés, pâtés, and terrines) are prepared and other foods are stored under refrigeration. The person in charge of this area is known as the "chef garde manger" or "pantry chef". Larger hotels and restaurants may have garde manger staff to perform additional duties, such as creating decorative elements of buffet presentation like ice carving and edible centerpieces.
Most merchants who worked outside noble manors at this time were associated with a guild, an association of persons of the same trade formed for their mutual aid and protection. Guilds would develop training programs for their members, thereby preserving their knowledge and skills. Charcuterie was the name of a guild that prepared and sold cooked items made from pigs. Through this organization, the methods of preparing hams, bacon, sausages, pâtés, and terrines were preserved. When the guild system was abolished in 1791 following the French Revolution of 1789, garde mangers took on the responsibility for tasks that had formerly been performed by charcutiers, who had difficulty competing with the versatile garde mangers due to the limited range of skills involved.
A role-playing game (sometimes spelled roleplaying game,[1][2] RPG) is a game in which players assume the roles of characters in a fictional setting. Players take responsibility for acting out these roles within a narrative, either through literal acting or through a process of structured decision-making regarding character development.[3] Actions taken within many games succeed or fail according to a formal system of rules and guidelines.[4]
There are several forms of role-playing games. The original form, sometimes called the tabletop role-playing game (TRPG or TTRPG), is conducted through discussion, whereas in live action role-playing (LARP), players physically perform their characters' actions.[5] In both of these forms, an arranger called a game master (GM) usually decides on the rules and setting to be used, while acting as the referee; each of the other players takes on the role of a single character.[6]
Several varieties of RPG also exist in electronic media, such as multiplayer text-based Multi-User Dungeons (MUDs) and their graphics-based successors, massively multiplayer online role-playing games (MMORPGs). Role-playing games also include single-player role-playing video games in which players control a character, or team of characters, who undertake(s) quests and may include player capabilities that advance using statistical mechanics. These electronic games sometimes share settings and rules with tabletop RPGs, but emphasize character advancement more than collaborative storytelling.[7][8]
Both authors and major publishers of tabletop role-playing games consider them to be a form of interactive and collaborative storytelling.[2][10][11] Events, characters, and narrative structure give a sense of a narrative experience, and the game need not have a strongly-defined storyline.[12] Interactivity is the crucial difference between role-playing games and traditional fiction. Whereas a viewer of a television show is a passive observer, a player in a role-playing game makes choices that affect the story.[13] Such role-playing games extend an older tradition of storytelling games where a small party of friends collaborate to create a story.
While simple forms of role-playing exist in traditional children's games of make believe, role-playing games add a level of sophistication and persistence to this basic idea with additions such as game facilitators and rules of interaction. Participants in a role-playing game will generate specific characters and an ongoing plot. A consistent system of rules and a more or less realistic campaign setting in games aids suspension of disbelief. The level of realism in games ranges from just enough internal consistency to set up a believable story or credible challenge up to full-blown simulations of real-world processes.
Role-playing games are played in a wide variety of formats, ranging from discussing character interaction in tabletop form, physically acting out characters in LARP to playing characters virtually in digital media.[17] There is also a great variety of systems of rules and game settings. Games that emphasize plot and character interaction over game mechanics and combat sometimes prefer the name storytelling game. These types of games tend to reduce or eliminate the use of dice and other randomizing elements. Some games are played with characters created before the game by the GM, rather than those created by the players. This type of game is typically played at gaming conventions, or in standalone games that do not form part of a campaign.
Tabletop and pen-and-paper (PnP) RPGs are conducted through discussion in a small social gathering. The GM describes the game world and its inhabitants. The other players describe the intended actions of their characters, and the GM describes the outcomes.[18] Some outcomes are determined by the game system, and some are chosen by the GM.[19]
A LARP is played more like improvisational theatre.[22] Participants act out their characters' actions instead of describing them, and the real environment is used to represent the imaginary setting of the game world.[5] Players are often costumed as their characters and use appropriate props, and the venue may be decorated to resemble the fictional setting.[23][24] Some live-action role-playing games use rock paper scissors or comparison of attributes to resolve conflicts symbolically, while other LARPs use physical combat with simulated arms such as airsoft guns or foam weapons.[25]
Single-player role-playing video games form a loosely defined genre of computer and console games with origins in role-playing games such as Dungeons & Dragons, on which they base much of their terminology, settings, and game mechanics.[21] This translation changes the experience of the game, providing a visual representation of the world but emphasizing statistical character development over collaborative, interactive storytelling.[7][8] 2ff7e9595c
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