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Urolithiasis is among the most common urologic disorders with high incidence and recurrence rates. High environmental temperatures, prevalence of the Western diet, obesity, age, gender, and race are among the common risk factors associated with this disease. The primary goal of evaluating these patients is to provide a simple, economic, and effective workup, which yields information that is directly applicable to providing relevant medical preventative measures. The management of urolithiasis requires a relevant history, targeted physical exam, appropriate chemistry, urinary and stone analyses results, radiological imaging to accurately identify number, location, and size of stones, as well as a metabolic evaluation. All stone formers whether single or recurrent should have a basic evaluation to identify any factors that may predispose to recurrent stone formation. Comprehensive metabolic evaluations are offered to patients at increased risk of recurrence or morbidity from stone disease, or have difficult to treat stones.

Urinothorax or presence of urine in pleural cavity is a highly unusual cause of pleural effusion. It is most commonly secondary to genitourinary trauma and obstructive uropathy. We here by present a case of urinothorax secondary to renal stone disease in a 5-year-old child with a solitary functioning kidney.

Objective To compare the non-contrast computed tomography (NCCT) scan-based parameters of ureteric stones affecting the outcome of extracorporeal shock wave lithotripsy (ESWL). Materials and methods We retrospectively evaluated the pre-procedure NCCT of 74 patients who had ESWL for solitary ureteric calculi of 5-20 mm in diameter. We assessed the age, sex, basal metabolic index (BMI), laterality, location, presence of double 'J' (DJ) stent, skin to stone distance (SSD), stone maximum diameter, Hounsfield unit (HU), Hounsfield density (HD), area, and volume. All those who had no stone on follow-up imaging within 30 days were declared successful while those who had residual stone were declared failures. Results The overall success rate was 78% (58/74). Sixty (81.1%) patients were male. The success of ESWL was correlated with lower SSD, Hounsfield units (HU) and Hounsfield density (HD). However, in multivariate analysis, SSD, Hounsfield unit, and stone area showed correlation with success of procedure but Hounsfield density failed to show correlation. The success rate in patients with stone HU 1000 were 93.9%, 69%, and 58.3%, respectively. Patients with lower BMI (30 kg/m2) and higher HD (>76 HU/mm). Conclusion BMI, SSD, stone Hounsfield units and Hounsfield unit density were strong predictors of outcome of ESWL for ureteric stone.

The potential of graphene for electronic applications originates owing to its exceptional room temperature carrier mobility. However, during the fabrication of electronic devices like field-effect transistors graphene is exposed to external environment that affects its carrier mobility. Also, the formation of dangling bonds at Si/SiO2 interface further degrades the mobility of graphene and hence influence the performance of graphene devices. In order to protect graphene from environmental conditions and preserve its fundamental electrical properties in such devices, here graphene is sandwiched between hBN layers (i.e. hBN/Graphene/hBN) and then the effect of e-beam irradiation on graphene structure is studied. To investigate structural disorder in graphene, Raman analysis was carried out which revealed no defects in graphene even for a high dose of e-beam irradiation. The electrical and magneto-transport measurements further confirmed the stability of these e-beam irradiated hBN-passivated graphene devices thereby demonstrating a mobility of 16,638 cm2/Vs and Quantum Hall plateaus at 9 T, respectively. Furthermore, different devices comprising Graphene/SiO2, Graphene/hBN and hBN/Graphene/hBN are studied for the interface analysis, which after e-beam irradiation revealed no defects and contaminations at the interfaces between hBN and graphene.

Modern supply chains are vulnerable to high impact, low probability disruption risks. A supply chain usually operates in such a network of entities where the resilience of one supplier is critical to overall supply chain resilience. Therefore, resilient planning is a key strategic requirement in supplier selection decisions for a competitive supply chain. The aim of this research is to develop quantitative resilient criteria for supplier selection and order allocation in a fuzzy environment. To serve the purpose, a possibilistic fuzzy multi-objective approach was proposed and an interactive fuzzy optimization solution methodology was developed. Using the proposed approach, organizations can tradeoff between cost and resilience in supply networks. The approach is illustrated using a supply chain case from a garments manufacturing company.

To form a smart production system, the effect of energy and machines&rsquo, failure rate plays an important role. The main issue is to make a smart production system for complex products that the system may produce several defective items during a long-run production process with an unusual amount of energy consumption. The aim of the model is to obtain the optimum amount of smart lot, the production rate, and the failure rate under the effect of energy. This study contains a multi-item economic imperfect production lot size energy model considering a failure rate as a system design variable under a budget and a space constraint. The model assumes an inspection cost to ensure product&rsquo, s quality under perfect energy consumption. Failure rate and smart production rate dependent development cost under energy consumption are considered, i.e., lower values of failure rate give higher values of development cost and vice versa under the effect of proper utilization of energy. The manufacturing system moves from in-control state to out-of-control state at a random time. The theory of nonlinear optimization (Kuhn&ndash, Tucker method) is employed to solve the model. There is a lemma to obtain the global optimal solution for the model. Two numerical examples, graphical representations, and sensitivity analysis of key parameters are given to illustrate the model.

The recovery of phosphates from biological wastewater treatment plants, through struvite crystallization, minimizes operational downtime and offers the potential for cost-effective recovery. The pilot-scale, fluidized bed reactor developed at the University of British Columbia (UBC) was found to be effective in recovering phosphate in the form of nearly pure struvite product, from an anaerobic digester centrate. The desired degree of phosphate removal was achieved by maintaining operating pH 8.0-8.2, and recycle ratio 5-9, to control the supersaturation conditions inside the reactor. The performance of the system was found to be optimal when the in-reactor supersaturation ratio was 2-6. In-reactor magnesium to phosphate molar ratio was found to be an important parameter to maintain system performance. In-reactor ammonium to phosphate molar ratio was also found to maintain a good correlation with phosphate removal. The influence of organic ligands on the struvite precipitation was investigated for a small molecular weight organic ligand, acetate, using a chemical equilibrium model PHREEQC. An acetate concentration below about 100 mg l(-1) was not found to affect the precipitation potential of struvite. Calcium and carbonate ion did not have any noticeable effect in struvite crystallization of struvite, under the operational concentrations utilized. Since the precipitation of calcium and carbonate compounds was controlled by kinetic factors, rather than thermodynamic solubility alone, the solid precipitates harvested were pure struvite, with undetectable impurities.

The two-dimensional (2D) layered electronic materials of transition metal dichalcogenides (TMDCs) have been recently proposed as an emerging canddiate for spintronic applications. Here, we report the exfoliated single layer WS2-intelayer based spin valve effect in NiFe/WS2/Co junction from room temperature to 4.2 K. The ratio of relative magnetoresistance in spin valve effect increases from 0.18% at room temperature to 0.47% at 4.2 K. We observed that the junction resistance decreases monotonically as temperature is lowered. These results revealed that semiconducting WS2 thin film works as a metallic conducting interlayer between NiFe and Co electrodes.

This paper develops a numerical model for simulating heat and moisture transfer through a porous insulation, with impermeable, adiabatic vertical boundaries, and with one horizontal boundary facing a warm humid ambient and the other facing a cold impermeable surface. The problem is modeled as one-dimensional, transient, multi phase flow with variable physical properties. The analysis has identified four phases of energy and moisture transport processes, and they are formulated by a system of transient intercoupled equations and several thermodynamic relations using the local volume averaging technique. The numerical model is validated by comparing with experimental data for different operating conditions and for times up to 600 h. The model predicts the temperature distribution, the heat transfer and the total moisture gain successfully. The predicted liquid distribution agrees with measured data for a period of up to 70 h. The interesting effects of pertinent parameters on the energy and moisture transfer in the porous insulation are investigated.

This article develops an analytical model for heat and water vapor transfer in flat-slab and round-pipe thermal insulations. The model is validated by comparing its predictions with available experimental data. The effective thermal conductivity of the insulation in the presence of condensation depends on seven design and operating variables. The effect of these variables is determined by a parametric study. The effective thermal conductivity increases with decreasing cold surface temperature until condensation begins to occur in the slab and then decreases gradually. For practical operating conditions, the effective thermal conductivity varies from about 1 5 to 15 times the dry-state value The computed data arc prc sented in the form of design curves which may be used to estimate the effective ther mal conductivity for flat-slab and round-pipe insulation systems

Broadband infrastructure is a key component of knowledge economy. Broadband service both on fixed and mobile networks are becoming an indicator of the knowledge economy. Globally it is viewed that countries with developed broadband infrastructures are working more efficiently and effectively towards social and economic growth. To achieve worldwide broadband connectivity level Government of Pakistan and industry must play a combine role for the betterment and improvement of the said industry. Government and market players must come up with innovative broadband packages that can capture the customer demand. This paper analysis market trends, customer expectation and socio-technical impact of broadband service in Baluchistan.

A simple empirical model to calculate solar spectral diffuse and global irradiance under cloudless skies is presented here. This formulation takes into account absorption of radiation by molecules such as O3, H2O and the uniformly-mixed gases. Attenuation by Rayleigh scattering and aerosol extinction are included. Aerosol attenuation is calculated through Angstrom's turbidity parameters α and β. The diffuse radiation is assumed to be composed of three parts: (1) Rayleigh-scattered diffuse irradiance; (2) aerosol-scattered diffuse irradiance; and (3) irradiance arising out of multiple reflections between the atmosphere and the ground. The global irradiance is the sum of these three components of diffuse irradiance plus the direct irradiance. The input parameters include an extraterrestrial spectrum, zenith angle, turbidity coefficient β, wavelength exponent α, ground albedo ϱg, water vapor content and ozone content. The model is shown to yield very good results up to air mass two when compared to accurate theoretical calculations. No comparisons with measured spectra are presented because of a lack of accurate specifications of input parameters. Results are presented to show the effect of variation of certain of the input parameters.

The spectral distribution of longwave atmospheric radiation arriving at the earth's surface is composed of contributions from atmospheric layers which absorb and re-emit longwave radiation. A procedure to estimate this radiation requires, as input, the temperature and pressure variations with altitude and the distribution of absorbing gases in the atmosphere. Such detailed information about the atmosphere at a given location and time is rarely known. However, local variation of the amount of water vapor is generally known, and ozone undergoes known seasonal variations. These two gases along with carbon dioxide are the main emitters of longwave radiation in the atmosphere. A rigorous technique to compute spectral atmospheric radiation is used together with atmospheric data from a Standard Atmosphere to examine the variation of spectral emissivity with the amount of absorbing gases in the atmosphere. A simple spectral correlation is thereby developed which is then applied to the other Standard Atmospheres utilizing their water vapor amount as the only input. Results obtained from this correlation are compared with those obtained from detailed computations for each Standard Atmosphere. Good agreement is observed at all the wavelengths considered except in a 1 μm region wherein the differences are somewhat larger. It is demonstrated that for any geographic latitude and season the spectral longwave atmospheric radiation can be computed from a simple correlation using precipitable water vapor amount as the only input parameter.

The correlation between diffuse and total horizontal radiation is reviewed and examined for data on the monthly average daily horizontal radiation collected at several Canadian stations. A regional correlation is developed based on Toronto-Montreal and Goose Bay data, which is valid for a large region. A solar building heat simulation study was performed using regional correlations. (SPH)

The objectives of this study are to compare statistically three models for estimating solar radiation on inclined surfaces and to recommend one that is general and accurate. The isotropic model, and Klucher's and Hay's anisotropic models are chosen for discussion. The hourly and daily formulations of these models are briefly described. Results show that they all produce large errors at steep slopes. The errors are minimum during the summer months. The isotropic model under-estimated consistently throughout the year resulting in the worst performance. Hay's model also under-estimated constantly but by a smaller amount. Klucher's model overestimated in the summer and under-estimated in the winter, but can be considered just as general and accurate as Hay's model for estimating insolation on inclined surfaces.

A statistical procedure has been employed to develop correlations between the hourly global horizontal radiation and its diffuse component. Several years', hourly radiation data from three Canadian stations and two French stations have been employed for this purpose. The relationships have been developed in dimensionless form which predict I d I o for particular solar altitudes when I I o is given. Under heavily cloudy conditions or when the sky is completely covered ( I I o ), diffuse radiation increases linearly with the global radiation. In this region, solar altitude has no bearing on the fraction of diffuse radiation. As I I o goes beyond 0.35, the effect of solar altitude begins to appear and the region immediately following this may be considered as partly-cloudy-skies conditions. In the beginning of this region, the diffuse component increases briefly with the increase in global radiation and then begins to decrease as the partly cloudy skies become clearer. At particular solar altitudes, a minimum value of the diffuse radiation is reached. The value of I I o where I d I o reaches its minimum value varies with solar altitude. The region beyond which a minimum value of I d I o is reached may be considered as mainly-clear-sky conditions. In this region, I d I o increases again with I I o , lower solar altitudes giving a higher percentage of diffuse radiation. Under partly cloudy skies and under clear skies, solar altitudes lower than 30° had a marked effect on the fraction of diffuse radiation. However, solar altitudes greater than 30° had minimal influence on the fraction of diffuse radiation.

A liquid-base active residential solar heating system employing flat-plate collectors was examined. The two particular objectives of this study were: (a) to determine the influence of the collector azimuth on the fraction of the total demand supplied by the solar system, and (b) to consider the effect of sky-diffuse radiation being non-isotropic and the hourly radiation being asymmetric around solar noon vs the symmetric-isotropic model. The study showed that the influence of the collector azimuth varied with the collector slope. For low-sloped collectors, the collector azimuth had minimal effect on the energy supplied by the solar system. The azimuthal orientation had maximum effect when the collectors were vertically sloped. The maximum amount of energy supplied by the solar system was always obtained from collectors facing the equator. The final results were obtained by using either the symmetric-isotropic model or the asymmetric-anisotropic radiation model. These results differed from each other only by about 5 per cent maximum. The former model produced conservative results. The above calculations were carried out using meteorological data from three Canadian locations with different climates. Yearly heating loads of 105, 106 and 107 MJ were employed at each location. Ratios of space-heating to service-hot-water loads were varied from 5 to 15.

Empirical equations have been developed which correlate the monthly average daily horizontal diffuse and beam radiation with the fraction of maximum possible number of bright sunshine hours. These correlations are based on measured data from three widely spread Canadian stations. Depending upon whether or not the total horizontal radiation is known, the two correlations for the diffuse radiation are: H d H =0.791−0.635 n N H d H o =0.163+0.478 n N −0.655 n N 2 . The correlation for beam radiation is: H d H o =0.176+1.45 n N −1.12 n N 2 , for n > 0 .

Insolation on south-facing inclined planes has been computed using hourly values of total and diffuse radiation, obtained from experimental data. Such a computation procedure is then compared with the widely used method by Liu and Jordan for obtaining daily insolation on surfaces tilted toward the equator. Very small differences are noted between the results obtained by the two methods. These differences are mainly due to three factors; (a) Liu and Jordan's formulation uses a theoretical day-length while the hourly method uses day-length as incicated by the radiation data; (b) hourly method takes into account the asymmetries of total and diffuse radiation around solar noon while the daily method implicitly assumes symmetry of the same; (c) the daily method assumes uniform atmospheric transmissivity to beam radiation throughout the day. On the other hand, the hourly method assumes constant atmospheric transmissivity for one hour only.

For most solar energy applications, it is necessary to predict the amount of global and diffuse radiation arriving on a horizontal surface at any specified location. Scientists have developed methods to achieve this using different input parameters. The purpose of this study is to compare statistically correlations for estimating the monthly average daily global/diffuse radiation incident on a horizontal surface and to recommend one in each catagory that best fits measured data from a number of locations chosen and is the simplest to use. The effects of using the new solar constant of 1367 W−2 in these correlations are also investigated. As a result, Rietveld's and Page's correlations are recommended for estimating monthly average daily global and diffuse radiation incident on a horizontal surface, respectively. In addition, these correlations seem to be just as accurate with the new solar constant.

This investigation presents experimental results of the effect of free convection upon forced convection. The case studied was a circular horizontal tube with uniform heat flux at the wall. Water was used as the working medium. Reynolds numbers ranged from 100 to 2000, Grashof numbers from 300 to 30,000 and Prandtl numbers from 4 to 9. The results indicated appreciable increase in the Nusselt number and a tentative correlation for the fully developed region is presented. The results are applicable to flat-plate solar collector design.

Optimum collector slope for a liquid base active solar heating system employing flat-plate collectors was investigated. The optimum collector slope was studied as a function of (a) collector area, (b) yearly total heating load and (c) the ratio of space heating load to service hot water load. Collectors facing equator only were considered. Such a system was studied in four different Canadian locations having widely different climates. Under the above conditions, optimum collector slope varied with the amount of collector area employed. The optimum collector slope was invariant with the yearly total load itself, or the space heating to hot water load ratio. Contrary to the widely held belief, for the four locations investigated, the optimum collector slope varied from lat. − 10° to lat. + 15°; depending upon fy, the fraction of load supplied by the solar system. When fy is in 10–20 per cent range, optimum collector slope is lat. − 10° and increases almost linearly to lat.+ 15° at fy in 80 per cent range. Consequently, when the fraction of load by the solar system is low, a flat roof may be profitably employed. On the other hand, when the fraction by the solar system is high, a south facing (for northern hemisphere) vertical wall may be profitably employed.

This chapter discusses the physics of the sun, the nature of the radiant energy emanating from its surface, spectral distribution, and the total quantity of that energy arriving just outside the earth's atmosphere. The sun is the star closest to the earth, and its radiant energy is practically the only source of energy that influences atmospheric motions and our climate. The sun is a completely gaseous body composed mainly of hydrogen. The spectral distribution of radiation arriving on the surface of the earth is indeed a function of its extraterrestrial distribution and the atmospheric constituents. The solar constant is the rate of total solar energy at all wavelengths incident on a unit area, exposed normally to rays of the sun at one astronomical unit. The temperature of the sun is calculated from two types of information: the solar constant and its spectral distribution. The chapter describes more recent values of the solar constant and its spectral distribution.

Publisher Summary Matter can emit electromagnetic radiation by molecular and atomic agitation. The spectrum of electromagnetic radiation encompasses γ rays, X rays, ultraviolet radiation, light, heat, radio waves, and radar waves. This chapter explores the thermal radiation portion of the spectrum of electromagnetic radiation. Thermal radiation, emitted by the agitation associated with the temperature of matter, is commonly called heat and light. Electromagnetic radiation is generally classified by wavelength, though frequency and wave number are also used. Frequency has the advantage over wavelength of not changing when radiation passes from one medium to another. The emissive power of a blackbody at any wavelength and temperature—called its spectral emissive power—is given by Planck's law. The chapter describes the radiant energy emanating from a blackbody. It focuses on evaluating solar radiation, arriving at a surface on the earth. The chapter explains the distinction between terms expressing quantity of energy and those denoting rate of energy.

Radiation over a certain bandwidth can be evaluated only by adding up the spectral values. On the other hand, the radiation over the entire solar spectrum can be computed either by integrating over the complete solar spectrum or by what may be called a broadband approach. This chapter discusses the parameterization method and the ASHRAE algorithm under the broadband approach. It also discusses parameterization models. When the atmosphere is clean, maximum energy is in ultraviolet and violet bands. However, with increase in turbidity, fraction in the infrared increases. The chapter presents separate expressions for direct, diffuse, and global irradiance. It also presents the clear-sky direct-insolation models.

The beam radiation is attenuated by the presence of clouds in its path and by the various elements of the cloudless atmosphere. The depletion of the direct beam by the clouds depends on the type of clouds, their thickness, and the number of layers. When the sky is completely covered by clouds, the number of bright sunshine hours recorded will be nil. Under such a condition, all radiation received on the earth will be of a diffuse nature. On the other hand, on a completely cloudless day, a certain number of bright sunshine hours will be recorded, and diffuse radiation will be quite minimal. The amount of diffuse radiation depends on both the solar altitude and the cloud cover. Under clear-sky conditions and for a given atmosphere, solar altitude is the governing parameter. The effect of cloud cover increases as the amount of sky covered by clouds increases, and it also depends on the geometric distribution of the clouds with respect to the solar beam.

This chapter discusses the integrated value of extraterrestrial solar radiation over all wavelengths. It illustrates mathematical formulations to determine irradiation at various surface orientations and for different time periods. The chapter further illustrates expressions for radiation on horizontal surfaces for different time periods—an hour, a day, a month, and so forth. It presents plots of the extraterrestrial hourly radiation on horizontal surfaces. Those plots demonstrate the effect of latitude and declination on the diurnal variation in insolation. Near the equator, the effect of declination is minimal. At high altitudes, the effect of declination is greater. The chapter further presents some examples of the diurnal variation of the extraterrestrial radiation on horizontal surfaces. The characteristic declinations for the hourly and daily irradiation remain the same. At the equator, the annual variation of the extraterrestrial radiation is minimal.

In order to assess the availability of solar energy arriving on the earth, the measurement of solar radiation at some locations is essential. This chapter discusses the instruments used to measure the various solar radiation fluxes, arriving on the earth. It further discusses the sources of errors and the methods of calibration. The chapter presents instruments for the measurement of broadband radiation. The chapter focuses on the three principal solar radiation fluxes: (1) direct, (2) global, and (3) diffuse. Detectors of the various instruments can be classified as calorimetric, thermomechanical, thermoelectric, or photoelectric. In many solar energy applications, it is necessary to measure insolation on inclined planes. Since pyranometers are calibrated in a horizontal upward direction, they may show a change in response when mounted in an inclined or downward direction. When global radiation is measured by a pyranometer and direct radiation is measured separately by a pyrheliometer, diffuse irradiance can be found by calculation. In meteorological applications, two types of optical filters are used: (1) absorption filters or (2) interference filters.

Publisher Summary This chapter discusses the motion of the earth around sun and around its polar axis, the angle between the earth's equator and the plane containing the sun–earth orbital system. It presents the trigonometric equations relating the position of the sun to a horizontal or an inclined surface. The chapter focuses on the relevant astronomical relationships that do not require a prior knowledge of solar radiation. The earth revolves around the sun in an elliptical orbit with the sun at one of the foci. The amount of solar radiation reaching the earth is inversely proportional to the square of its distance from the sun. Solar time is based on the rotation of the earth about its polar axis and on its revolution around the sun. A solar day is the interval of time as the sun appears to complete one cycle about a stationary observer on earth. The solar day varies in length through the year. The chapter presents an overview of the calculation of the sun–earth distance, declination, and the equation of time.

Publisher Summary This chapter presents the basic formulas related to the configuration factors. It explains a configuration factor relationship between the elementary surfaces dA1 and dA2 at a distance r from each other. The chapter describes the reciprocal nature of the configuration factors. Unit-sphere method is especially suitable for evaluating configuration factors between an inclined surface and the sky and between the inclined surface and the ground. The sky diffuse radiation is usually anisotropic. If the distribution of the sky diffuse radiation anisotropy is known, the sky dome could be divided into several parts in such a way that the radiation from each part might be assumed isotropic. The configuration factors from such parts of the sky and the collector, and hence the irradiation from such parts of the sky on the collectorcould be computed.

Solar radiation emanating from the sun is attenuated before reaching the ground by the earth's atmosphere; that can be classified into two broad types: (1) atmosphere without clouds and (2) atmosphere with clouds. This chapter describes the constituents of a cloudless atmosphere. Maximum radiation on the earth is received under cloudless and clear skies. Most solar devices operate when radiation is at a maximum or at least above a certain threshold level. The cloudless condition is important from both the utilization and the control point of view. The chapter explains the conditions under cloudless skies. It illustrates the computation of direct and diffuse radiation through turbidity parameter. When monochromatic radiation traverses a medium, each molecule attenuates energy. The number of molecules a solar ray strikes before reaching the ground is related to the distance traversed by the ray. The chapter presents a method of estimating atmospheric ozone that can be used in the absence of real data. It discusses a number of atmospheric aerosol models and their optical properties.

Publisher Summary When radiant energy is incident on a surface, it may be partly absorbed, partly reflected, and partly transmitted. The properties of a surface or a material associated with those three functions are called its absorptivity, reflectivity, and transmissivity. The fraction of the total incident energy associated with those properties is termed “absorptance,” “reflectance,” and “transmittance.” This chapter presents that determining an accurate value of albedo is very important in evaluating the total insolation on a building or on a solar energy collecting device. It discusses the albedo of a number of natural surfaces. Albedo is generally measured by two back-to-back pyranometers, mounted in a horizontal position, a few meters above the underlying surface. The pyranometer facing the sky measures the global incident solar radiation, and the one facing the earth measures the reflected energy.

This chapter explains measured or predicted global and diffuse radiation received on a horizontal surface and transposes these quantities onto an inclined plane. The total radiation incident on the plane is composed of three components—namely, direct radiation, radiation reflected from the ground, and sky diffuse radiation. Under realistic skies, the diffuse intensity is not uniform, and varies with the sky conditions. The chapter presents the results of calculations for the daily sky diffuse radiation incident on south-facing tilted surfaces. The total amount of radiation incident on an inclined plane is composed of beam, ground-reflected, and skydiffuse components. There is very little difference between the isotropic and the anisotropic ground-reflected irradiation. Anisotropy of the ground-reflected radiation is large when the sun is near the horizon. The chapter discusses elementary procedures to compute total irradiation on inclined planes.