LINKS for MECHANICS of VISION

Post 619 –by Gautam Shah

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MASKING of OPENINGS Part -III -Framing
https://interiordesignassist.wordpress.com/2016/01/25/masking-of-opening-part-iii-framing/

MASKING of OPENINGS Part -II
https://interiordesignassist.wordpress.com/2015/09/23/masking-of-openings-part-ii/

MASKING of OPENINGS Part -I
https://interiordesignassist.wordpress.com/2015/08/30/masking-of-openings-part-I/

FRAMING of OPENINGS
https://interiordesignassist.wordpress.com/2015/08/04/framing-of-openings/

ARCHITECTURAL WINDOWS and VISION in-out
https://interiordesignassist.wordpress.com/2014/11/17/architectural-windows-and-vision-in-out/

ARCHITECTURAL WINDOWS and the MEANING
https://interiordesignassist.wordpress.com/2014/11/16/architectural-windows-and-the-meaning/

ARCHITECTURAL WINDOWS and MECHANICS of VISION https://interiordesignassist.wordpress.com/2014/11/18/architectural-windows-and-mechanics-of-vision/

GLASS and PERCEPTION

https://interiordesignassist.wordpress.com/2014/08/31/glass-and-perception/

 

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CLIMATE and our BODY

Post 618 –by Gautam Shah

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A climate affects our body system very profoundly. The effects are warmth-cold, pressure and moisture, all sensed by the skin. Five types of sensations are involved with the skin such as, Touch-Pressure (mechanic-o receptors), Cold-Warmth feeling (thermo receptors), Pain and Itch. Cold is a consequence of contraction of blood vessels, and warmth is felt due to dilation of blood vessels, both felt by the same receptors.

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Cold Comforter > Wikipedia image ART by Henri de Toulouse-Lautrec (1864-1901)

Our body functions as a thermal equilibrium system. The thermal bearing capacity has upper and lower limits. The pain occurs at the upper limit of 52°C /126°F, and has a lower limit of 3°C/37°F. The optimum or the comfort level temperature depends on the level of acclimatization. In certain acute work conditions like mines, metal smelting plants, textile plants, cold storage, the efficiency or productivity depends on the endurance level and adaptability of the body. A body may endure or adopt to certain abnormal conditions for a period of time, but there may be side effects. The side effects may be realized in a different form and at a different time.

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Day time sleepers > Image on Wikipedia by Julio Rojas + Flickr as Day_Sleepers

Our body, gains heat from the atmosphere, and also dissipates excess heat to it, to maintain thermal equilibrium. The human body maintains itself at an average temperature of 98.4°F / 37°C. There are many minor variations in body temperature, which are considered normal. Body temperature is highest in the evening and lowest in the morning, within a range of 1.5°F / 1°C. Infants have a very imperfect mechanism for regulation of body temperature. A fit of crying may elevate and a cold wash may lower the body temperature. Aged persons have a low metabolism and so maintain a lower body temperature. It takes much longer for an aged person to gain or dissipate body heat. Female body temperature is slightly lower than male.

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Homeostasis temperature regulation > Wikipedia image

The type of food one takes affect the body temperature. High protein foods increase the body temperature. The act of ingestion and food digestion raise the body temperature. Exercise increases the body temperature, because only 25% of muscular energy is converted into mechanical work, rest comes out as body heat. Atmospheric conditions like, atmospheric temperature, humidity and movement of air, affect the efficiency of heat exchange from the body, and so the body temperature.

There are THREE types of heat generating processes in the human body. Conversion of food matter into useful energy is a continuous heat generating process. Muscular activities, like even sedentary work or sleeping, are heat generating processes. Lastly, certain infections and dysfunctions within the body, elevate or lower the body temperature by extra ordinary rate of heat generation, or weakened heat dissipation mechanisms. Of all the energy produced in the body only 20% is utilized, rest 80% is surplus heat.

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Hindu bathing ceremony > Wikipedia image by Balaram Mahalder

Normal skin temperature is between 31° and 34°C. As the air temperature approaches the skin temperature heat loss from the body gradually decreases, vasomotor regulation will increase the body temperature to 34°C to maintain the heat loss, but if air temperature is higher, the convective heat loss may not work.

As long as temperature of the opposite surface or object (sun, fire, radiator) is below skin temperature, the body can lose heat by radiation. But once it reaches the equilibrium occurs, body will rather gain heat by radiation.

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Hot arid climate Cooking > Wikipedia image by User: (WT-shared) Shivya at wts wikivoyage

When the convective process is inoperative and radiation heat gain is positive, the body can maintain the thermal balance by evaporation. Evaporation can occur if air has velocity and appropriate humidity (low). Even in case of very high humidity conditions a high velocity air can remove the humidity.

A person exposed to a constant high rate of sweating and permanent vaso-dilation can have a lot of physical strain with loss of work efficiency.

The body must not only release all the excess heat that is generated from within the body, but all the excess heat as gained from the environment. Heat is lost from the body by radiation (60%), evaporation (25%), by convection and conduction (15%).

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Beach Hammock > Wikipedia image > Photo taken by flickr user ReubenInStt

Heat is lost through radiation, if there is a difference in temperatures of opposing surfaces. Evaporation heat loss is controlled by the level of humidity in the air (dryer the air, faster the evaporation), temperature of the air, body and rate of air movement. Body dissipates heat through evaporation by perspiration, sweat and exhalation of air. Convection occurs when the air in the vicinity of skin becomes hot, expands, decreases in density, and elevates to allow cooler air in its place. Rate of heat convection from body depends on the difference in temperatures (skin & surrounding air) and rate of air movement. Conduction depends on the difference between the body temperature and the contact object.

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Working in very Hot conditions > Wikipedia image ART by Peder Severin Kroyer (1851-1909) from Fra Burnmeister og Wain’s Iron foundry

The body continues to accelerate or decelerate the heat loss till it reaches equilibrium. Heat loss is accelerated by several body functions like perspiration, high transfer of heat to the skin by increased blood circulation (vaso-dilatation). When these prove to be insufficient, sweating occurs. In hot climates the heat loss rate is lower due to unfavourable atmospheric conditions. But by lowering of the body heat generation (lower metabolic and muscular activity), the net amount of heat to be dissipated can be reduced. But this requires some time to take effect. On immediate basis when the heat loss is not balanced with heat gain, the `heat stroke’ occurs. In cold climates the heat loss is higher, so heat balance is achieved by conservation of heat and by appropriate heat gain. Heat production is raised by certain reflex secretions (adrenaline, thyroxine), higher intakes of food (increased metabolic activity) by reflex shivering (muscular exercise) and by sufficient insulative protection. The body may control the heat loss by vaso-constriction (lower blood supply), and depressed sweating.

Many physical, chemical and bacterial agents disturb the heat regulation mechanism and cause fever. These may be due to increased heat production or reduced heat loss, or both.

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Cold-Blood creatures or Reptiles > Wikipedia image Attribution: Postdlf from w

In a reptiles and amphibia heat regulation mechanism is absent. Their body temperature rises or falls with the atmospheric temperature. Hence they are called cold blood animals. In abnormal temperature conditions they regulate the body temperature by suitable habitat. In winter they go deep into burrows or in hibernation (minimize the metabolic heat generation). Mammals and birds are known as hot blood creatures, because the heat regulation mechanism is well developed, and they are able to maintain a level of body temperature.

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Hot blood animals > Wikipedia image derivative work: Mariomassone

Comfort of an occupant in an environment also depends on subjective variables or individual factors:

1 Acclimatization: exposed to new conditions a person shortly (approx. 30 days) acclimatizes own-self.

2 Age and sex of a person: Older persons take much longer to adjust to temperature change, and as a result slightly higher temperature. Women also have slower metabolic rate than men so prefer a little higher temperature.

3 States of health: Activity / heat output in watts

  • Sleeping   70
  • Sitting, typing    130/160
  • Standing, working at a bench   160/190
  • Walking   220/290
  • Digging   440/580
  • Sustained hard work   580/700

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SCALING the SPACES -Issues for design-9

Post 617 –by Gautam Shah

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Architectural spaces become relevant through scaling. Scaling creates an organization, where sub-elements are allied to form a holistic domain. The space when interpreted as Large-Small, Wide-Narrow, Tall-Shallow, deep-short, etc. relates to some adjacent reality, or some remembrance. But spaces are perceived in terms task accommodation (functional adequacy), anthropometric needs, sensorial reach capacities, social interactions vibes (privacy, intimacy), degree of objectivity and subjective involvements. Scaled space sizes bring forth proportions, modulation, analogy, sequencing, balance, incidental and regular occurrences, harmonics etc.

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Tashichhoe Dzong at Thimpu, Bhutan > Wikipedia image by Rainer Haebner

 Shape and Scale of a space have no relationship. Exterior or Interior shape of a space entity can mislead the perception of the scale. Similarly a very extensive space will need ‘stepping or connecting elements’ within the perceptible range. Spaces that have been substantively transgressed inward-outward, the shape may have been deformed, but the scale remains a relevant factor.

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Street scene at Ephesus at Anatolia Turkey Wikipedia image by Ad Meskens

Scale is a matter of sensorial experience. Scaling is predictable and manageable in spaces within the known range of perception (visual, aural, touch or proximity, etc.). The strangeness or alienation of a space is reduced by introducing scalable elements such as: repetitions, harmonics, rhythmic evolution, structured patterning, sensory gradations, acceleration deceleration, graduated changeovers, linkages, relationships through modulation and proportioning, etc.

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Turbine Hall, Tate Modern, London > Wikipedia image by Hans Peter Schaefer

A space is perceived to be small, adequate or large in terms of various tasks, and in terms of responses it offers such as echoes, reverberation, reflection, illumination, glares, depth and width of vision. With the same size and shape of space these elements offer varied experiences, some seeming related and some confounding. Within a space, the size changes (and thereby the proportions) to provide variegated settings for different activities. These changes in a space also cause marked shift in human behaviour. Designers, intentionally avoid as well as include such confirmations and contrasts, but even then surprises do occur. Such spatial manipulations and surprises are further exploited by the users for individualization.

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German Chancellery Berlin > Wikipedia image by Bruckels

Environment is a consistent space modulator. The environment changes the spatial scale on moment to moment basis. Since these both, seem to occur in conjunction, in design, we try to inculcate one with the other. An environment scales the space more effectively in the peripheral areas the core remains less dynamic. Again a design tool to shift the space. Scaling by environment becomes exciting because natural illumination, solar gains, etc., are directional.

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Environmental variations and space scale modulation > Sky Garden atop the ‘Walkie-Talkie > Wikipedia image by user: Colin / Wikimedia Commons / CC BY-SA 4.0

Our perception faculties are directional and nodal. Hearing and vision, are bi-nodal. Vision, smell and taste faculties are frontal, whereas touch is non-local. These variations in perception affect how elements scaling the space are perceived. Shapes like convex, concave or parabolic curvatures modify the movement. Planes that slope away or towards the user, mean opening or closing of the form. Right and left turns have culture specific relevance which may override presumed biological preferences.

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Sydney Opera House > Wikipedia image by Enoch Lau

Directional emphasis for scaling is also very important for orientation. Gravity offers a parallel to the ground plane, the horizontal, and a counter effect as the vertical. The horizontal and vertical make the scaling of space resolutely simpler, and every other scaling to be dynamic or unstable. The stability of gravity and stability of vertical allows forms to be wider at base, the inevitable force for space scaling.

At Absolute level the size is perceived as the difference between the Length and Width of a space. It is seen as a narrow or wide entity. The height confers its own scale of narrowness or broadness to the space. Height accentuates or de-emphasizes the character of the space nominally contributed by the relation between the Length and the Width. The equality of Length and Width of space marks a balance. The orientation of smaller or larger size gives a feel of a deep and shallow space.

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Street, Sana’a, Yemen > Wikipedia image by Rod Waddington from Kergunyah, Australia

Narrow spaces have length as the dominant scaling factor. Narrowness of the space could be a carryover of the past experiences or a psychological condition. Narrow spaces have domineering effect of the side barriers, more so if these are opaque, that is without any break or transgression. The scaling elements in such spaces are like, the doors, windows, columns, corners, benches, niches, public address systems, focussed illumination spots, air movement-delivery and ventilation nodes (fans, air conditioners, heaters), stair entrances, junctions (cross corridors, floor cutouts), signboards, parapets, ash trays, etc.

Scaling of narrow spaces can be experienced in art exhibition galleries, which tend to be linear spaces, but similar areas in museums show master pieces for distanced viewing. The hall of mirrors, Versailles is a classic example of long space; opaque on one side and fully windowed on the other side.

Size in a neighbourhood space is perceived in terms of the reach. Whatever is within reach (of touch, vision, hearing or smell) is considered the neighbourhood space. Here the recognition of reach also defines its functional adequacy for interpersonal relationships and related behaviour. Occupation of large public spaces is challenging. One needs points for anchorage, a direction for orientation, presence of other human being (or an animal like a dog) for confirmation, and a ready strategy for exit in any exigency, but all scaled to personal relevance.

A hazy or foggy atmosphere dulls as much as a bright sunny day highlights the spatial elements through enhanced light and shadow differentiation.

Past midnight in absence of nearby background noises, the far-off sounds are acutely heard, increasing the extent of the neighbourhood space.

Hospital wards seem very strange (large) to a patient, in comparison to domestic (small home) spaces, because the space size proportions are different and surfaces are harder and less absorbent (causing reverberation to be different), background noises are less passive, illumination levels are brighter during day and night, furniture and furnishings are unusual, in addition to sickness and weakened mental faculties.

Occupation of domains with unusual proportions (combinations of lengths, widths, and height) and sizes require extra efforts of accommodation.

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Old Roman Theater at Ephesus > Wikipedia image by Eoe gian at En Wikipedia 

Amphi theatre performances require large frill dresses, loud dialogue delivery, spaced out movements -theatrics, real or make-believe sub-zoning of the stage. Large space audiences can be reached through public address system, a large podium, stage setting, colour-light highlighting, etc. People in large spaces like airports and marriage halls reach out to others through wild gestures, shouting etc.

Shape configurations are closed or open ended, and show potential of scaling through distension, contraction, or attachments. The spatial scaling when include such edges formations, the subsets become very complex entities.

This is the 9 th article of 20 topics series on ISSUES for DESIGN

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SKY LIGHTS

Post 616 –by Gautam Shah

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Skylight in Rotunda of Centro Cultural Banco do Brasil, Rio de Janeiro > Wikipedia image by anna carol from Rio de Janeiro, Brasil 

Sky lights have been used in buildings for ages for sourcing natural light into deep set interiors of buildings. These are set atop a roof, as a clerestory between roofs, or high up in the wall. These openings are basically meant for illumination and ventilation, occasionally for observing stars and other celestial objects and for cultivating plants in protected spaces. Such openings are minuscule size holes to very large gaps, often covering the room’s entire surface. Skylights allow maximum sky-component (SC) compared to any other opening system.

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Roof light Complex of Sultan Qalawun (1284) as Mausoleum, Madrasa and Maristan, Cairo, Egypt > Wikipedia image by Ahmed Al. Badawy from Cairo, Egypt

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The Ras el-Tin Palace in 1931 Alexandria, Egypt > Wikipedia image Attribution: Bundesarchiv, Bild 102-12201 /  CC-BY-SA3.0

In early periods such gaps were open or covered with a fabric, lattice, wooden slats or louvres. It was with the use of glass that such gaps became fixed-transparent panes. Roof-light openings with wood frames required frequent repair-replacements, and were not weather tight. During Victorian Era, with metal construction, skylights became very popular. Virtually every urban row house of the late 19th and early 20th C relied on a metal-framed skylight to illuminate the enclosed stairwells.

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Large skylight Star Ferry Pier Hong Kong > Wikipedia image by VictoriaDFong

Skylights are were shaped as a pyramid because glass panes were flat. Very large skylights were designed with a structural geometry of curved half cylinders or domes, made from smaller units. These mainly bulged outward towards the sky for rain water drainage. Roof window or day lighting began to be flat or single-double curved structures with pre-formed toughened glass plates, plastics and fiber composites. Inverted daylights bulging inward into the interior volume are made from plastics and fiber constructions. Daylight tubes are inverse lights, as an inward projection of a reflective tube or a bottle.

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Argentina Industrial Shed Roof lights > Wikipedia image

 Roof Lanterns were once very popular as interior and exterior illumination systems. These were timber-framed structures, usually octagonal, polygonal or circular in shape, placed as a crown over a turret or dome of a building to admit light. The lanterns’ structures were initially filled with wood slats (louvres) but later covered with glass. These were tall and thin volume multi pane glass structures. Roof Lantern or steeple lights during the day brought in shadow less illumination into the interior space. The lantern structures over the topmost point or pinnacle of a roof, glowed at night with little illumination inside the buildings. The glowing lanterns marked the presence of the building in the dark night-scape.

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Roof Lantern over Dome of Florence Baptistry 1150 AD > Wikipedia image by Richardfabl

 Roof Lanterns have derived from Orangeries, structures first built in 16th C in France and Italy. An orangery is similar to a conservatory or greenhouse. It is generally located in the free ground of an estate or building. The name reflects the original use of the building as a place where citrus trees like orange were often wintered in tubs under cover, for surviving through harsh frosts, though not expected to flower and fruit.

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Mexican Hothouse, Jardin des Plantes 1834-36 Example of Glass+Metal Orangery architecture Wikipedia image

Orangeries originated from the Renaissance gardens of Italy. The orangeries became fashionable in ordinary residences of France, Germany and the Netherlands. Early orangeries had large windows but opaque roofs. Glazed roofs were developed in the early 19th C. Early orangeries, as existed in Great Britain and France in 16th C, were buildings that could be covered by planks and sacking and heated in the cold season by stoves.

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Pavilion of remaining part of Old Municipal Market 1903 of Rio de Janeiro, Brazil > Wikipedia image by Stella Dauer from Sao Bernardo Brasil

During the Georgian era, buildings with large footprints (floor area), the interiors were dim and dark even on sunny days, and in absence of electric or gaslight candle power was the only source of illumination. Roof lanterns were used to illuminate the stairwell landings and other areas of home. The key element of a lantern, the glass was hand made and very expensive, limiting the use of roof lanterns in the homes of elite.

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Surviving building on Princess street 18th C Wikipedia image by Kim Traynor

The Crystal Palace built for the Great Exhibition of 1851 inspired people for greater use of glass in roof structures of buildings, and the Industrial revolution provided the necessary affluence and technology. Modern Roof lanterns were used for illuminating domestic billiard rooms, reception rooms and kitchens, and in public buildings such as hotels, in places of education, town halls and public libraries.

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Royal Botanical Gardens, Kew, London, estb 1759 / Palm house built 1844-48 > Wikipedia image by DAVID ILLEF. Licence: CC-BY-SA 3.0

DORMER WINDOW: A dormer is an attic window located in the sloping gable roof, on the main face of the building. A dormer is an extension of the attic and provides accessible or functional height right to the front edge of the room, which is used for placing a bed or study unit. The roof over a dormer is slopped cross way from the slope of the main roof. The dormer windows are design-matched with the window of a lower floor, creating an impression of a taller window, both from outside as well as inside. Dormers add a visual interest to the nominally plain gable roof surface. In England when fire laws did not permit architectural projections such as eaves, etc., the front wall was extended as a parapet to cover up the roof end. The parapet was articulated with embattlements, crenels, embrasures and dormers. Wall dormers are lower floor windows extended up to roof, parapet top, or even higher, as a true or dummy window, with all features of an highly ornamental window surrounds. False or blind dormers were added to visually balance roof-leveled other appendages, like chimneys, lanterns etc. Dormer openings are also called a doghouse, because the form of the dormer resembles the pet-house. Attic level barn windows shaped like a dormer used for taking in or out hay are called hay-windows.

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Dormer Windows Dunstaffnage Castle. Argyll and Bute Scotland > Wikipedia image by Otter

Types of Dormer windows: A gable dormer, has sloped roofs on both sides. A hipped dormer has a roof sloping on three sides including front. An insert dormer is set back from the sloping edge of the roof so has some sloping roof on its front bottom side. A turret dormer has multi angled hipped roof. A French segmental dormer has lower floor window continuing above by breaking the line of roof eaves. A fanlight dormer and Eyebrow dormer has rounded top window. A shed or lean-to dormer has single slope roof. An extended shed dormer has roof line extending beyond the main roof line. An all glass contemporary dormer has all sides formed of fixed glass or jalousie.

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Dormer at Chateau d’Azay-le-Rideau > Wikipedia image by LonganimE

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Vimana Architecture (Lit. Aeroplane =light airy structure at top) > Wikipedia image by Onef9day

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DESIGN SPECIFICATIONS

Post 615 –by Gautam Shah

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Primary instinct for a human effort is to create a Recipe or Process. We tend to perceive an item by hypothetically enacting its process. First step is compilation of a list of physical inputs (ingredients). Second step is forming lists of things to do, how to do and not to do (human interventions). Third step is planning the sequences in time. Fourth step is readying tools required for various processes. A fair mix of all FOUR steps can offer an object, but not a desired entity. The end result is conjectural. In real design work intentions are additionally transmitted through drawing documents and other forms of surrogates.

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Oven Cooking > ART by Jean-Francois Miller (1814-1875)

Item or design specifications have been used for execution, manufacturing, fabricating, erecting, for procuring ready-made objects, and also for effecting various services. The term Design here means any scheme, as such orally conveyed, written, drawn, or otherwise implied.

A Design or Scheme specifies aspects like : constituents, processes of combining, synthesizing a coherent entity or system, method of care and handling the men, materials, tools, equipments and the entity itself as it is being created.

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Elevator Design by German Engineer Konrad Kyeser (1405) Wikipedia image

When a design (recipe) is specified for a product, and once readied (with reasonable sincerity), a client has to pay even if it fails on acceptability count. As a result, writing Item or Design Requirements is not an assuring process, unless the specifiers have had recent experience, at designing nearly Identical Items, and fully comprehends all aspects of the design problem.

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Design confusions > Image attribution: Wiki4des at English Wikipedia

Specifications for a Designed Object

A Designer prepares design specifications, (materials + procedures + conditions of origin), so that the contractor or vendor can provide the stated item. The contractor or vendor gets very exact data, but little freedom to use alternative materials or execute it differently. If there is an uncommon item, the contractor will invariably charge more for the extraordinary effort or customization. This process does not assure that in spite of a sincere execution and diligent supervision a functional product will be delivered. The Item specifications specify ‘physical adequacy of the item while seeking a hypothetical performance’.

A contractor or vendor is better aware of latest materials, processes, technologies and their costing as available in the market, In comparison to any specification formulator like a designer. A contractor or vendor, if allowed to provide, can offer an item that surpasses the one conceived in the ‘item or design specifications’. This cause was identified by US Air-force and made it mandatory to procure entities by PERFORMANCE SPECIFICATIONS, through the ITEM or DESIGN SPECIFICATIONS. A performance specification states the exact requirements of performance of an entity, and no materials + procedures + conditions of origin are given. This is an appreciable method but very difficult to implement. Performance of some of entities cannot be checked-validated over a longer time span (e.g. Operative suitability of a submarine beyond 20 years).

Performance specifications are partially used in many works with item specifications. For example, 6/7 decades back many builders were asked to refer to Standards for Cement, Sand, Aggregates, Water, Mixing procedures and testing methods for quality to be achieved. This is now replaced by pre-mix cement concretes of assured quality. This a way of relying on the performance, than Materials+Processes methods.

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Ready-mix Concrete > Wikipedia image by High Contrast

Specifications for acquiring some ready-made objects can be Performance specifications but tend to be even more restrictive. A specifier (buyer-acquirer) of a ready-made item of the market shelves has no way of verifying a product, so relies on average standards followed by the Industry, or match with some ‘super’ supplier’s (top product in the market) specifications. Failing either of the conditions, one, has to pay the extra cost of customizing a regular or standard item. In the later case the assurance nominally available for the regular or standard item are unlikely to be offered for the altered form.

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