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The purpose of this paper is to introduce flexible dye-sensitized solar cells (FDSSCs).

In the third generation solar cells, glass was used as a substrate, which due to its high weight and fragility, was not possible to produce continuously. However, in flexible solar cells, flexible substrates are used as new technology. The most important thing may choose a suitable substrate to produce a photovoltaic (PV) device with optimal efficiency.

Conductive plastics or metallic foils are the two main candidates for glass replacement, each with its advantages and disadvantages. As some high-temperature methods are used to prepare solar cells, metal substrates can be used to prepare PV devices without any problems. In contrast to the advantage of high thermal resistance in metals, metal substrates are dark and do not transmit enough light. In other words, metal substrates have a high loss of photon energy. Like all technologies, PV devices with polymer substrates have technical disadvantages.

In this study, the development of FDSSCs offers improved photovoltaic properties.

The most important challenge is the poor thermal stability of polymers compared to glass and metal, which requires special methods to prepare polymer solar cells. The second important point is choosing the suitable components and materials for this purpose.

Dependence of efficiency and performance of the device on the angle of sunlight, high-cost preparation devices components, limitations of functional materials such as organic-mineral sensitizers, lack of close connection between practical achievements and theoretical results and complicated fabrication process and high weight.

The purpose of this paper is to demonstrate the application of analytical decision making during the selection of engineering entities in an engineering design setting.

The paper develops a quantitative method for wire rope selection and uses handbook data to demonstrate the use of the method in selecting a suitable type and size of wire rope for the hoisting/hauling mechanism of a hypothetical manual winch.

Wire rope data can be processed into forms that are more readily useable in a quantitative selection method. Moreover, computer software such as Microsoft Excel may be used in the selection process, so long as the data are in suitable form.

The selection of engineering entities often occurs in engineering design processes. An information processing approach to wire rope selection has been developed and demonstrated. The method demonstrated in this paper should be applicable in other situations in which a need for the selection of engineering entities arises.

1. From the information given to the Committee by members of the trade the following conclusions were drawn : (i) Four main types of product are sold under a name commonly including the word “vinegar,” namely (a) the product of the alcoholic and acetous fermentation of a saccharine liquid, the sugars in which are derived entirely or mainly from the saccharification of starch by the diastase of malt; (b) the product obtained by the distillation of (a); (c) the product of the acetous fermentation of a distilled alcoholic fluid; (d) the product, with or without colouring and/or flavouring matter, obtained by diluting acetic acid to an appropriate strength. In addition, strong acetic acid is available in various strengths, with or without added colouring and/or flavouring matter, labelled in various ways to indicate relationship with vinegar, (ii) The commonly accepted minimum standard for the purposes of the Food and Drugs Act is 4 per cent. w/v of acetic acid. (iii) Malt Vinegar as obtained by the brewing process may contain up to 8 per cent. w/v of acetic acid. This is diluted to the required strength and three strengths are commonly recognised in the trade, being known respectively as Nos. 16, 20 and 24, which correspond approximately to acetic acid contents of 4, 5 and 6 per cent. w/v. (iv) Malt vinegar as generally sold from bulk is the No. 16 quality and contains from 4 to about 4·75 per cent. w/v of acetic acid. That sold in bottles is usually the No. 20 quality, but there is also a small sale to the public of No. 24 quality. (v) The colouring matter commonly used in vinegar is caramel, although one or two manufacturers, probably as a result of the present shortage of caramel, may use other colouring matters. (vi) The value of brewed vinegar as a condiment does not depend solely upon the acetic acid content. Other constituents add body and aroma while some have a buffering effect which makes the product less sharp to the taste than a dilution of acetic acid containing the same proportion of free acid. (vii) Dilute solutions of acetic acid, with or without added colour and/or flavour, are now commonly sold under the name “non‐brewed vinegar” and are sometimes preferred for pickling purposes and for use on fried fish. (viii) The acetic acid content of such solutions, as usually sold, falls within the range of 4 to 5 per cent. w/v. (ix) Concentrated products, often known as “vinegar essence,” frequently contain about 50 per cent. w/v of acetic acid and before use require dilution with eleven times their volume of water; products are also available which require to be diluted with as much as 17 or as little as 5 times their volume of water. (x) An excise licence is required by any person “who shall make, prepare, extract, distil, purify or sell any liquors prepared or capable of being used or applied to the purposes of vinegar or acetous acid made for sale, not being a dealer in or retailer or seller of such vinegar or acetous acid only.” An unlicensed person cannot lawfully produce artificial or non‐brewed vinegar by adding colouring matter to the liquid obtained by diluting strong acetic acid. 2. In normal times malt vinegar is prepared by the alcoholic and acetous fermentation of an infusion of malted barley with unmalted barley and with or without other cereals. The process of manufacture is characterised by the fact that the starch in the cereals is converted into sugars by the action of the diastase in the malt prior to the fermentation processes. An element of complication has, however, been introduced into the framing of a definition as a result of war‐time difficulties. In 1942, in order to secure an increased output of “malt vinegar,” the Ministry of Food approved the addition of sugar to the wort. The amount that may be added must not exceed 15 per cent. of the sugars present in the wort as a result of the action of diastase on the starch, but since the sugars in the infusion which undergoes fermentation are no longer derived entirely from the starch by the hydrolytic action of the diastase of malt, the product no longer conforms to what the Committee would regard as the appropriate peacetime definition of malt vinegar. It was stated by the manufacturers that the analytical characterisations of the vinegar obtained in this way arc within the range appropriate to genuine malt vinegar of peacetime quality, and that no difference is detectable by the ordinary user. The Committee desires, however, to record its view that this use of sugar should be regarded as a war‐time expedient and should be discontinued as soon as the requisite cereals are again in full supply. 3. Distilled vinegar is prepared, as the name implies, by distilling vinegar. It is understood that the only distilled vinegar now on the market in this country is that prepared by the distillation of malt vinegar, and the Committee recommends that the name “distilled vinegar” without any further qualification should be applied only to distilled malt vinegar. 4. Spirit vinegar is prepared by the acetous fermentation of a distilled alcoholic liquid. As thus prepared it contains about 10 per cent. weight in volume of acetic acid and for retail sale it is commonly diluted to a strength of 4 to 5 per cent. 5. The nomenclature of the products obtained by diluting acetic acid, with or without the addition of colour, has been a matter of controversy in the vinegar trade for many years, and the Committee received representations on the subject on behalf of the Malt Vinegar Brewers‘ Federation and the Association of Non‐Brewed Vinegar Manufacturers. 6. The Malt Vinegar Brewers' Federation, while advocating that these products should be known as “artificial” or “imitation” vinegar, raised particular objection to the current practice of describing them as “non‐brewed vinegar.” Their argument was that the term is misleading as to the source, nature, substance and quality of the article and that its use on a label is an offence under Section 6 of the Food and Drugs Act, 1938 (since replaced by Regulation 1 of the Defence (Sale of Food) Regulations, 1943). It was claimed that the term indicated merely that a mashtun had not been used in the manufacture of the product and that it might be applied with equal propriety to other kinds of vinegar, for example, wine vinegar, molasses vinegar, etc. The attention of the Committee was also directed to the fact that in the Dominions and other countries where the labelling of foods is more fully controlled than here, these products are required to be so labelled as clearly to distinguish them from products made by a method which includes a process of acetous fermentation, and reference was made to the statement issued by the Society of Public Analysts and Other Analytical Chemists in 1935, after consultation with the Malt Vinegar Brewers' Federation, recommending the use of the description “artificial” or “imitation.” 7. On behalf of the Association of Non‐Brewed Vinegar Manufacturers it was claimed that the Society of Public Analysts had not consulted them before issuing their statement and that the use of the description “artificial” or “imitation” would have a serious effect on sales since it would convey to the public the idea that the product was inferior to “vinegar.” It was pointed out that the term “vinegar” originally connoted sour wine, and it was suggested that malt vinegar was equally an “imitation” of the original article and also “artificial” in the sense that it is manufactured by a process which is controlled by artificial means. 6. The two trade organisations differed in their statements as to the period during which the term “non‐brewed” had been in use. Whereas the Federation suggested that it had only been used during the last five years, the Association claimed that it had been in use to a gradually increasing extent for at least 20 years and that for more than twelve years they had recommended its use whenever they had been asked to advise in regard to labels. The Association agreed that the general use of the name by manufacturers dated from the case of Sutton v. Tame which came before the County of London Sessions Appeals Committee in 1937 and which is generally regarded in the trade as a test case on the nomenclature of vinegar. The proceedings were originally instituted under Section 2 of the Food and Drugs (Adulteration) Act, 1928, as the result of a sale of coloured diluted acetic acid when “table vinegar” was demanded. After hearing much evidence from both sides the Appeals Committee decided that the sale of a substance as “vinegar” or “table vinegar” without any qualification or explanation as to its origin being given by the seller to the purchaser implied that the product had been produced by a process of fermentation. In announcing this decision, the Chairman of the Appeals Committee remarked that “the fact that a very large majority of manufacturers add such words as ‘wood,’ ‘non‐brewed’ or similar words of that description to the products shows, in the opinion of the Committee, that the words “table vinegar” are not considered by the custom of the trade sufficient to describe it.” (Analyst, 1937, 62, 607.) 9. The manufacturers of the products consisting of diluted acetic acid have regarded these remarks as justifying the use of the name “non‐brewed vinegar,” but the Committee was informed on behalf of the malt vinegar brewers that this interpretation was not accepted by them and that had it not been for the war they would have taken all possible steps to challenge the name under the provisions of Section 6 of the Food and Drugs Act, 1938. The present position, however, according to the evidence available to the Committee, is that practically all manufacturers of the product are using the description “non‐brewed” on labels, and that the quantity sold is nearly equal to that of malt vinegar. 10. In reviewing the various arguments put before it the Committee has primarily had regard to the protection of the consuming public. If “non‐brewed vinegar” was about to be marketed for the first time the Committee would have considered that the description “artificial vinegar” was more appropriate than “non‐brewed vinegar,” and better calculated to convey to the public the idea of a product which embodies some, but not all, of the properties of malt vinegar. On the other hand, the Committee feels bound to take cognisance of the fact that the description “non‐brewed” has been in use to a greater or lesser extent for several years; that the description did not attract any adverse comment from the Chairman of the London Sessions Appeals Committee in 1937; and that no instance of a successful prosecution under Section 30 (1) of the Food and Drugs (Adulteration) Act, 1928, or Section 6 of the Food and Drugs Act, 1938, has been brought to its notice. The description “non‐brewed” probably conveys no more to the general public than that the product is something different from malt vinegar, but the Committee would hesitate to say that the description is misleading. 11. In short, it appears to the Committee that the importance of the description attached to this product can easily be exaggerated, and that if, as it suspects, the term “non‐brewed” conveys little to the general public the proper remedy is better instruction. It is suggested that the publication of a simple and impartial statement of the facts would help them to appreciate the nature, substance and quality of the different types of vinegar on the market. For the purpose of this report, therefore, and in the absence of an authoritative ruling as to the appropriate designation of the product, the Committee has adopted the alternative descriptions “artificial vinegar” or “non‐brewed vinegar.” 12. In regard to the nomenclature of solutions of acetic acid of strengths in excess of that suitable, without further dilution, for use as vinegar, it was suggested to the Committee that for the protection of the public it was desirable that such preparations should not be described by any designation incorporating the word “vinegar,” however qualified. Names such as “edible acetic acid,” or “acetic acid of edible quality” were put forward as suitable alternatives, but they are open to the suggestion that only those with technical knowledge would appreciate their significance. To the majority of persons the adjective “edible” would convey the impression that preparations so labelled are suitable for use without further dilution, whereas, in fact, they have hitherto commonly contained 50 per cent. of acetic acid and sometimes considerably more. On the other hand, it was urged that the chief purchasers of those products are fish fryers, who are thoroughly familiar with their use and that it would be unreasonable to prohibit the inclusion of the word “vinegar” in the name of a product which on dilution gives a liquid identical with that frequently sold under the name “non‐brewed vinegar.” The essential requirement is that the user should appreciate that the product is not suitable for use in the form in which it is purchased, and that he should know exactly how to dilute it to the appropriate strength. 13. The Committee was informed that several of these products are at present sold without any indication on the label of the extent to which they should be diluted before use. Although the matter is not strictly within its terms of reference, the Committee wishes to record its opinion that such information should be required to appear on labels, particularly since there is considerable variation in the strengths of the products now on the market. In the opinion of the Committee, vague directions such as “Dilute to taste” are not a sufficient protection. 14. A further aspect of the sale of concentrated products to which the attention of the Committee was directed was the danger that may arise from distribution to the public in small bottles. Although, again, the matter may not be strictly within its terms of reference the Committee suggests that consideration might well be given to prohibiting such sales provided interference with the legitimate sale of the higher concentrations of acetic acid, labelled as such, can be avoided. It would also be a further safeguard if all these products were required to conform to a single standard of strength and it is suggested that a strength of from 50 to 60 per cent. weight in volume would be appropriate. 15. If on further examination it is found practicable to give effect to those suggestions, there will be less necessity to rely on the name given to the product to secure adequate protection. Among the names at present in use are “Vinegar Essence,” “Concentrated Vinegar Essence,” “Wood Vinegar Essence” and “Non‐Brewed Vinegar Essence”; there are also a number of products sold under proprietary names, most of which suggest some association with vinegar. The Committee is of the opinion that the statement made by the Chairman of the London Sessions Appeals Committee in the case referred to above, to the effect that the name “Vinegar” without qualification indicates a product obtained by fermentation, is equally applicable to the concentrated preparations. It therefore considers that the name “Vinegar Essence” is misleading. In this report the descriptions “concentrated artificial vinegar” or “concentrated non‐brewed vinegar” have been adopted corresponding to the descriptions adopted for dilute solutions. The Committee recommends that products sold under a proprietary trade name should be required to use one of those descriptions either in addition to or instead of the trade name. 16. The Committee accordingly recommends the following definitions for the various descriptions of vinegar : “Malt Vinegar” means the product containing not less than 4 per cent. weight in volume of acetic acid, CH3.COOH, made by the alcoholic and subsequent acetous fermentation without intermediate distillation of an infusion of malted barley with or without unmalted barley or other cereals, the starch of which has been saccharified by the diastase of malt; and includes the product obtained by fermentation of a cereal infusion as aforesaid to which infusion has been added sugar in amount not exceeding 15 per cent. of the sugars present in the infusion as a result of the saccharification by the diastase of malt. It may contain added colouring matter. “Artificial Vinegar” or “Non‐Brewed Vinegar” means a solution of acetic acid of edible quality, with or without added colouring and/or flavouring matter, containing not less than 4 per cent. weight in volume and not more than 8 per cent. weight in volume of acetic acid, CH3.COOH, the acid not being wholly produced by a process of acetous fermentation; but does not include such a solution containing neither colouring nor flavouring matter unless so sold or described as to lend an intending purchaser to believe that he is purchasing a description of vinegar. “Concentrated Artificial Vinegar” or “Concentrated Non‐Brewed Vinegar” means a solution of acetic acid of edible quality, with or without added colouring and/or flavouring matter, containing not less than 50 per cent. and not more than 60 per cent. weight in volume of acetic acid CH3.COOH, the acid not being wholly produced by a process of acetous fermentation; but does not include such a solution containing neither colouring nor flavouring matter unless so sold or described as to lead an intending purchaser to believe that he is purchasing a description of concentrated vinegar. “Spirit Vinegar” means the product, with or without added colouring matter and containing not less than 4 per cent. and not more than 15 per cent. weight in volume of acetic acid, CH3.COOH, obtained by the acetous fermentation of a distilled alcoholic liquid. “Distilled Vinegar” means the product, with or without added colouring matter and containing not less than 4 per cent. weight in volume of acetic acid, CH3.COOH, obtained by the distribution of malt vinegar.

TO say that the Twenty‐fourth S.B.A.C. Show was an unqualified success is perhaps to gild the lily. True there were disappointments— the delay which kept the TSR‐2 on the ground until well after the Show being one—but on the whole the British industry was well pleased with Farnborough week and if future sales could be related to the number of visitors then the order books would be full for many years to come. The total attendance at the Show was well over 400,000—this figure including just under 300,000 members of the public who paid to enter on the last three days of the Show. Those who argued in favour of allowing a two‐year interval between the 1962 Show and this one seem to be fully vindicated, for these attendance figures are an all‐time record. This augurs well for the future for it would appear that potential customers from overseas are still anxious to attend the Farnborough Show, while the public attendance figures indicate that Britain is still air‐minded to a very healthy degree. It is difficult to pick out any one feature or even one aircraft as being really outstanding at Farnborough, but certainly the range of rear‐engined civil jets (HS. 125, BAC One‐Eleven, Trident and VCIQ) served as a re‐minder that British aeronautical engineering prowess is without parallel, while the number of rotorcraft to be seen in the flying display empha‐sized the growing importance of the helicopter in both civil and military operations. As far as the value of Farnborough is concerned, it is certainly a most useful shop window for British aerospace products, and if few new orders are actually received at Farnborough, a very large number are announced— as our ’Orders and Contracts' column on page 332 bears witness. It is not possible to cover every exhibit displayed at the Farnborough Show but the following report describes a wide cross‐section beginning with the exhibits of the major airframe and engine companies.

This paper aims to evaluate the suitability and feasibility of the four most likely urban spaces for mixed use development – brownfields (contaminated lands); greenfields (open, undeveloped areas); greyfields (closed or dying shopping centers and empty parking lots); and redfields (underperforming, foreclosed commercial real estate).

Literature about and studies of mixed use development projects in America and Britain were reviewed, and so too were specific examples of the four candidate urban spaces. The authors then analyzed which spaces succeeded as mixite and which failed.

Brownfields are often not successfully transformed into usable mixite; nor are greenfields. The cost and regulatory complication of removing pollution from brownfields is too often prohibitive, and greenfields are too far away from urban core areas. By contrast, greyfields and redfields appear to be far more suitable spaces for mixed use development projects.

Most government policies urging redevelopment projects in America and Great Britain prefer brownfields as the space deemed most suitable for mixite. Contrary to this view, it appears that unpolluted spaces, such as redfields and greyfields, that do not need extensive environmental remediation, are typically better candidates for mixite.

Federal and State Governments began to explore more subtle alternatives for accessing private sector resources in the delivery and operation of public facilities. The purpose of this paper is to examine the types of infrastructural projects most suitable using public‐private partnership (PPP) for executions and identify the critical success factors in PPP on infrastructural projects with a view to strengthening the partnership between the public (government) and private sector. The overall goal is to enhance infrastructural projects delivery in Nigeria.

The primary data consists of survey questionnaires, drawn based on the identified factors on existing literature on critical success factors (CSFs). The structured questionnaires were administered on participants that were involved in the execution of PPP projects, either during the initial stage, construction stage or maintenance and operating stages in Lagos State.

The results of the mean score ranking indicate that transportation, which include roads, rails and airports construction ranked highest followed by provision of electricity and water. Real estate and educational construction projects ranked lowest in terms of suitability of execution using PPPs. However, the result of the one‐way analysis of variance (ANOVA) indicates that, there was no significant difference in the suitability of PPP for execution of the types of infrastructural projects delivery. The paper further identified nine CSFs in public‐private partnerships as follows: competitive procurement process, thorough and realistic assessment of the cost and benefits, favorable framework, appropriate risk allocation and risk sharing, government involvement by providing a guarantee, political support, stable macroeconomic condition, sound economic policy and availability of suitable financial market. The study, however, showed that well organized and committed public agency; social support; project technical feasibility and multi‐benefits objectives are the CFSs that are most important to the private investors. On the other hand, factors such as transparency in the procurement process; shared authority between public and private sector; thorough and realistic assessment of the cost and benefits; commitment and responsibility of public and private sector and strong and good private consortium are the CSFs that are most important to the public clients.

The results indicated that there was no significant difference in the suitability of PPP for execution of infrastructural projects delivery. This shows that PPP is suitable for all types of infrastructural projects. What needs to be done is to ensure that all the success factors responsible for successful implementations of PPPs are well structured in a way that its optimum performance can be guaranteed. Also, in identification of the critical factors in PPP it would help to develop a body of PPP knowledge. This knowledge would help in the establishment of relevant laws, regulations and guidelines and in the development of efficient frameworks for best PPP practices.

Because of its lower dielectric constant and loss tangent, and its greater surface smoothness, fused silica is very suitable for use in the KU band and above, but its cost is very high. The purpose of this paper is therefore to select a new substrate which competes with fused silica on the grounds of lower cost; to adapt the hybrid technology to this new substrate; to show ,comparing the measured performances of a filter realised on fused silica and on this new substrate, that the latter is suitable for MICs in the wide band, but not in the narrow band; and to describe an application of this substrate in the 22–24 GHz band. Thus, after an investigation of the electrical parameters and of the costs of different substrates, Duroid was selected and compared with silica. This substrate is composed of a non‐woven glass microfibre reinforced by polytetrafluorethylene; its microwave quality is theoretically almost similar to that of the fused silica one but its cost is much lower. The adaptation of hybrid technology on this substrate, notably in order to use beam lead and die semiconductor components with thermocompression bonding as a connection method, involved the use of a copper foil laminated on Duroid. This paper describes the process that has been perfected: selective electroplating of gold on copper, compatibility of etching solutions of gold and copper, attachment and connection methods of semiconductors, substrate attachment in a package, etc. A comparison of the performances of a filter realised on fused silica and on Duroid gives the following conclusion: Duroid is suitable for wide band circuits, but not for narrow band circuits because of its instability under stress test temperatures (−20 to 80°). In this last case, silica will be preferred. A transmitter‐receiver in the 22–24 GHz band for radio links is described.

Finding an appropriate place for temporary housing after an earthquake is one of the main challenges of disaster risk management, especially in developing countries. Therefore, it is necessary to create pre-disaster location plans for the homeless population. This study aims to systematically find safe places and select suitable sites according to influential factors.

The research methodology used is a descriptive–analytical method. A field survey with a quantitative–qualitative approach is applied to recognize physical vulnerabilities and select suitable sites for temporary settlements. Due to the occurrence of several earthquakes in recent decades around the city of Isfahan, Iran, this area has been studied. Fuzzy analytic hierarchy process, geographic information system and rapid visual screening have been used for data analysis.

According to the site selection and vulnerability criteria and their prioritization, the findings indicate that 60% of the study area is vulnerable. Moreover, vacant lots, stadiums and public green spaces that can be used as multi-purpose sites are the most appropriate options for the temporary settlement.

The research criteria are generalizable and can be used for decision-making, concerning urban fabric vulnerability and site selection of temporary housing in cities exposed to earthquake risk.

Cultural features, accessibility, land conditions, the slope and type of land, availability and construction materials were addressed in locating temporary settlements. In addition to vacant lots and open spaces, safe buildings were also identified for temporary housing, and religious minorities and similar communities were considered.

A substantial number of production assets in the offshore oil and gas industry are facing operation beyond their anticipated design life, thus necessitating a service life extension program in the future. Selection of the most suitable strategy among a wide range of potential options to extend the lifetime of equipment (e.g. re-using, reconditioning, remanufacturing, refurbishing and adding on safety/process control measures) remains a challenging task that involves several technical, economic and organizational complexities. In order to tackle this challenge, it is crucial to develop analytical tools and methods capable of evaluating and prioritizing end-of-life strategies with respect to their associated costs and quantifiable benefits. The paper aims to discuss these issues.

This paper presents a life-cycle cost-benefit analysis approach to identify the most suitable life extension strategy for ageing offshore assets by taking into account all the capital, installation, operational, maintenance and risk expenditures during the extended phase of operation. The potential of the proposed methodology is demonstrated through a case study involving a three-phase separator vessel which was constructed in the mid-1970s.

The results from the application case indicate that the capital expenditure (CapEx) accounts for the largest portion of life cycle cost for the replacement strategy, while risk expenditure (RiskEx) is the major contributor to costs associated with life extension. A sensitivity analysis is also conducted to identify factors having the greatest impact on the optimum life extension solution, including oil price, production rate and money interest rate.

In the past, the decisions about life extension or replacement of in-service equipment were often made in a qualitative way based on experience and judgment of engineers and inspectors. This study presents a “quantitative” framework to evaluate and compare the costs, benefits and risks associated with life extension strategies and subsequently to select the best strategy based on benefit/cost ratios.

To the best of authors’ knowledge, no studies before have applied life cycle assessment and cost-benefit analysis methods to prioritize the potential life extension strategies in the oil and gas industry sector. The proposed approach not only assists decision makers in selecting the most suitable life extension strategy but also helps duty holders reduce the costs corresponding to life extension execution.