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The Colebrook equation for determination of hydraulic resistances is implicit in fluid flow friction factor and hence it has to be approximately solved using iterative procedure or using some of the approximate explicit formulas developed by many authors. The purpose of this paper is to compare different Lambert W based solutions of the Colebrook equation and to make comparisons among them and identify some constraints in applicability of certain solutions.

Alternate mathematically equivalents to the implicit Colebrook equation in explicit form with no approximation involved actually exist.

These alternate equations were developed using Lambert W‐function. The paper compares various implementations of the Lambert W methodology and shows that some of these are less able than others to yield solutions using modern computer hardware. This is because the functions require the evaluation of terms with numerical values outside the ranges that can be expressed on most computers.

Some of existed transformations cannot be applied for high values of relative roughness of inner pipe surface and the Reynolds number. This limitation applied only for computer computations. Other presented transformations do not sufferer of this limitation.

Presented procedures can be easily implemented in a computer code. Recommended solution can be used in all cases that can occur in engineering practice.

The paper shows some possible practical procedures for solution of the transformed Colebrook equation. Accuracy analysis and comparisons of presented formulas are also performed and recommendation for use is shown.

[In view of the approaching Conference of the Library Association at Perth, the following note on the Leighton Library may not be inopportune. Dunblane is within an hour's railway journey from Perth and has a magnificent cathedral, founded in the twelfth century, which is well worthy of a visit.]

THE topics of the Library Association Conference and the election of the Council of the Association naturally absorb a great deal of attention this month. To deal with the second first: there were few novelties in the nominations, and most of the suggested new Councillors are good people; so that a fairly good Council should result. The unique thing, as we imagine, about the Library Association is the number of vice‐presidents, all of whom have Council privileges. These are not elected by the members but by the Council, and by the retiring Council; they occupy a position analagous to aldermen in town councils, and are not amenable to the choice or desires of the members at large. There are enough of them, too, if they care to be active, to dominate the Council. Fortunately, good men are usually elected, but recently there has been a tendency to elect comparatively young men to what are virtually perpetual seats on the Council, simply, if one may judge from the names, because these men occupy certain library positions. It, therefore; is all the more necessary that the electors see that men who really represent the profession get the seats that remain.

This paper aims to derive the conditions under which a financial services firm will want to hire a compliance services company and show how much money they should spend.

This paper uses a mathematical model to show the intuition behind many of the compliance decisions that cost financial services firms billions every year.

This paper finds that hiring compliance firms may save banks and brokerages money. However, their advice may lead to an embarrass de riches – whereby the lower compliance costs and higher profit advantages they confer may lead to more regulation. Regulators may furthermore tighten regulation – with the expectation that financial service firms will adapt somehow. This paper presents a fresh perspective on the Menon hypothesis, deriving conditions under which financial regulations help the competitiveness of an international financial centre.

The paper represents one of the first and only models of compliance spending by financial services firms.

This paper provides five potential policy responses for dealing with ever ratcheting financial regulations.

The paper hopefully launches literature on the compliance service industry – and the buy-or-do decision to engage in financial services compliance. This paper finds that efficient compliance can hurt firms, by encouraging regulation. This paper shows how firms can forestall the extra regulation that comes with easier internet and computerised monitoring.

This study aims to develop a compact analytical models for undoped symmetric double-gate MOSFET based on carrier approach. Double-Gate (DG) MOSFET is a newly emerging device that can potentially further scale down CMOS technology owing to its excellent control of short channel effects, ideal subthreshold slope and free dopant-associated fluctuation effects. DG MOSFET is of two types: the symmetric DG MOSFET with two gates of identical work functions and asymmetric DG MOSFET with two gates of different work functions. To fully exploit the benefits of DG MOSFETs, the body of DG MOSFETs is usually undoped because the undoped body greatly reduces source and drain junction capacitances, which enhances the switching speed. Highly accurate and compact models, which are at the same time computationally efficient, are required for proper modeling of DG MOSFETs.

This paper presents a carrier-based approach to develop a compact analytical model for the channel potential, threshold voltage and drain current of a long channel undoped symmetric DG MOSFETs. The formulation starts from a solution of the 2-D Poisson’s equation in which mobile charge term has been included. The 2-D Poisson’s equation in rectangular coordinate system has been solved by splitting the total potential into long-channel (1-D Poisson’s equation) and short-channel components (remnant 2-D differential equation) in accordance to the device physics. The analytical model of the channel potential has been derived using Boltzmann’s statistics and carrier-based approach.

It is shown that the metal gate suppresses the center potential more than the poly gate. The threshold voltage increases with increasing metal work function. The results of the proposed models have been validated against the Technology Computer Aided Design simulation results with close agreement.

Compact Analytical models for undoped symmetric double gate MOSFETs.

The purpose of this paper is to investigate the chemical, optical and photovoltaic properties of titanium dioxide/reduced graphene oxide (TiO₂/rGO) photoanodes immersed in natural Roselle and synthetic (N719) dyes for dye-sensitized solar cell (DSSC) application.

TiO₂ mixed with rGO were doctor-bladed on fluorine doped tin oxide (FTO) glass substrate. The chemical and optical properties of TiO₂/rGO photoanodes immersed in Roselle and N719 dyes were characterized using Fourier-transformed infrared (FTIR) and ultraviolet–visible (UV–vis) spectroscopies, respectively. The DSSC’s photovoltaic performances were tested using Visiontec Solar I-V tester at standard illumination of AM1.5 and irradiance level of 100 mW/cm².

The presence of anthocyanin dye from Roselle flower was detected at 604 nm and 718 nm. TiO₂/rGO+Roselle dye sample revealed the smallest energy gap of 0.17 eV for ease of electron movement from valence band to conduction band. The TiO₂/rGO-based DSSC fabricated with Roselle dye had a power conversion efficiency, ƞ of 0.743 per cent higher than TiO₂/rGO photoanode sensitized with N719 dye (0.334 per cent). The obtained J-V curves were analyzed by a single-diode model of Lambert W-function and manual optimization to determine the internal electrical parameters of the DSSC. The average and uncertainty values of J_sc and ƞ were evaluated at different R_sh range of 1362 Ω to 32 k Ω.

R_s values were kept constant during optimization work.

New ideality factor of TiO₂/rGO-based DSSC was re-determined around 0.9995.

The third Annual Meeting of the Library Association to be held in Manchester should prove to be as profitable as the former meetings there. The manifold interests of the great cotton city, its activities, commercial and intellectual, its intense artistic life—so curiously at variance with its apparently materialistic atmosphere—its many libraries, some of them with real traditions; these things should go to make the 1921 meeting memorable.

With this number the Library Review enters on its ninth year, and we send greetings to readers at home and abroad. Though the magazine was started just about the time when the depression struck the world, its success was immediate, and we are glad to say that its circulation has increased steadily every year. This is an eminently satisfactory claim to be able to make considering the times through which we have passed.

Routine general practice (GP) care is rarely comprehensively described in clinical trials. This paper examines routine GP care within the lifestyle approach to managing panic (LAMP) study. The aim of this paper is to describe/discuss routine GP care for panic disorder (PD) patients within both study arms in the LAMP study. An unblinded pragmatic randomised controlled trial in 15 East of England GP practices (2 primary care trusts). Participants met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for PD with/without agoraphobia. Follow-up measures recorded at 20 weeks/10 months following randomisation. Control arm, unrestricted routine GP care (practice appointments, referrals and prescriptions). Trial arm, occupational therapy-led lifestyle treatment comprising lifestyle review of fluid intake, diet pattern, exercise, caffeine, alcohol and nicotine. Primary outcome measure: beck anxiety inventory. At baseline, participants attended 2-3 times more GP appointments than population average, reducing at 10 months to 1.6 times population average for routine GP care and 0.97 population average for lifestyle arm. At 10 months, 33% fewer referrals (6 referrals; 0 mental health) than at baseline (9 referrals; 2 mental health) were made for lifestyle arm patients compared with 42% increase (from 12 referrals; 8 mental health at baseline to 17 referrals; 7 mental health) in GP care arm. Selective serotonin reuptake inhibitors were prescribed most often. Benzodiazepines and beta-blockers were prescribed more often than tricyclic against current clinical guidelines. In conclusion, we found that PD patients at baseline were high healthcare resource users. Treatment in both study arms reduced resource use. Routine GP care requires further review for this patient group.

Suggests that most managers (other than those in marketing) take the view that too much money is spent on marketing. Adumbrates that the accountant may be able to contribute to improved decision making in marketing with regard to expenditure as an investment outlay rather than current expenses. Stresses, herein, that the concern for accounting is with marketing assets and their intangibility. Discusses further assets, valuation and investment and portrays these with the aid of tables and figures. Sums up by saying that a strong case can be made for recognizing many examples of marketing outlay as investments in assets rather than current operating expenses, showing new light on attitudes towards marketing decision‐making and financial reporting.