Search

A set of generalised charts are presented in this article as a design aid for hydrologic sizing of grass filter strips. The charts express the volume of runoff and the peak flow rate from a grass strip and the residence time in terms of the size and surface and subsurface characteristics of the grass strip as well as the size and surface characteristics of the area draining to the filter strip. These charts are developed by using a mathematical model based on a kinematic-wave formulation of overland flow and Green-and-Ampt formulation for infiltration. The results are obtained in terms of dimensionless parameters and generalised through the principle of hydrologic similarity. An example is included to demonstrate the use of the charts in a practical design problem.

A simple method requiring only hand calculations is presented in this study that enables the use of the Green and Ampt infiltration model beyond the rain duration. The method takes into account that the runoff and infiltration processes continue for some period of time after the rain stops. Both the ground surface and subsurface characteristics are considered. A conjunctive overland flow-infiltration mathematical model is employed for this purpose. A kinematic-wave approach is used to model the overland flow, and the Green and Ampt equations are employed to calculate the infiltration rates. The governing equations are expressed and solved in terms of dimensionless parameters to enable the generalization of the results based on the principle of hydrologic similarity. A four-point finite difference scheme is used to solve the governing equations. The results are presented in chart form. An example application of the proposed method is included.

This technical note is an extension of a previously reported hydrologic study of vegetative filter strips to calculate sediment trap efficiencies. It presents a set of charts developed using predetermined numerical solutions to the governing equations for overland flow, infiltration, and mass balance of suspended sediments in overland flow. Kinematic-wave equations are used for overland flow, the Green and Ampt equations are employed for infiltration, and the Aberdeen equation is adopted for sediment removal. The governing equations are written and solved numerically in terms of a set of dimensionless variables. The solutions thus obtained are generalized using the principle of hydrologic similarity and presented in chart form. The results show that the trap efficiency is affected by the subsurface conditions, surface conditions, and sediment characteristics. The charts presented can be used to quantify the impact of each parameter. Among the typical hydrological design parameters, the flow length...

This paper presents a set of generalized charts that can be used as an aid for quick hydrologic evaluation of vegetative filter strips to determine the runoff residence time and reductions in storm runoff volume and peak discharge. These charts are developed by using the predetermined numerical solutions to the governing equations for the overland flow and infiltration processes. Kinematic wave equations are used for overland flow and the Green and Ampt equations are employed for infiltration calculations. An explicit finite-difference scheme is employed to couple and solve these equations. The basic mathematical model is verified by using a set of published experimental data. The model is extended to incorporate a design inflow and the governing equations are written and solved numerically in terms of a set of dimensionless variables. The solutions thus obtained are generalized by using the principle of hydrologic similarity and presented in chart form.

A physically based mathematical model is developed in this study for the hydrologic process taking place in a bioretention filter. The hydrologic storage equation is adopted to determine the variation of water depth in the ponding area. The Green and Ampt equations are used to model the movement of water in the underlying storage zone, or soil filter, taking into account the finite depth of the filter. The perforated drain pipes placed at the bottom of a soil filter are represented by atmospheric pressure at this location. The ponding area and the soil filter equations are coupled through the infiltration term. The governing equations are written in terms of a set of dimensionless parameters and are solved numerically by using an explicit finite-difference scheme. The solutions to the dimensionless governing equations are also in terms of dimensionless parameters, and they can be generalized on the basis of the principle of hydrologic similarity. A series of solutions is obtained for numerous and ...

This paper presents a set of pollutant removal efficiency charts that can be used as an aid for quick evaluation of existing, retrofitted or trial-designed dry detention basins. They can also be employed for preliminary sizing of new extended dry detention basins as well as their water quality outlets. These charts are developed using the predetermined numerical solutions to the flow routing and the suspended solids routing equations. The flow routing is based on the hydrologic storage equation, and the pollutant routing procedure is based on the complete-mixing concept and settling of suspended solids under turbulent conditions. A finite difference scheme is used to solve these equations. The basic mathematical model is verified by using a set of published experimental data. The equations are then written and solved numerically in terms of a set of dimensionless variables. The solutions thus obtained are generalized using the principle of hydraulic similarity and presented in chart form. Dry detention ba...

A simple method is presented to size infiltration structures like infiltration basins and trenches to control storm water runoff. The runoff hydrograph is assumed to be trapezoidal in shape with a peak runoff rate calculated using the rational formula. Given the watershed time of concentration and the allowable runoff rate, the method determines the required size of the infiltration structure. A practical application section is included to demonstrate the use of the method.Key words: rational method, infiltration basin, infiltration trench, capture volume, storage time.

A design aid is presented for sizing stormwater infiltration structures. The proposed procedure is based on the hydrological storage equation for an infiltration structure coupled with the Green and Ampt infiltration equation. For the filling process, the two equations are solved simultaneously using a numerical method, and the results are presented in chart form. These charts are useful to determine the maximum water depth in an infiltration structure. For the emptying process, the governing equations are integrated analytically resulting in an algebraic equation that can be solved for the emptying time explicitly. A practical application is included to demonstrate the ease of the suggested procedure.

Snowmelt runoff presents an enhanced threat of environmental damage. Soluble impurities which have accumulated in the snow during winter months are transported to the lower portion of the snow cover early in the melting season due to melt-freeze cycles. These contaminants are removed rapidly at very high concentrations within the first fractions of snowmelt runoff causing sudden bursts of enriched pollutants. This paper reports a physically-based mathematical model to simulate the enrichment process in a snow cover. The model is based on the liquid water flow, heat transport, and pollutant transport equations. These nonlinear partial differential equations are solved simultaneously using a six-point implicit finite difference scheme.

A simple design aid is presented for quick preliminary sizing of flood-control detention basins and outlet structures. The design objective is to control the postdevelopment flood volume rather than the peak discharge. Alternatively, the method can be used to control downstream channel erosion caused by postdevelopment flows. The detention basins considered have a single outlet, which can be of either orifice or weir type. The design aid is based on the predetermined solutions to the reservoir-routing equation. The hydrologic storage equation is used for this purpose. To evaluate the channel-erosion tendencies, a generic bed-load formula is employed. All the equations are written in dimensionless form, and the solutions are obtained in terms of a set of governing dimensionless parameters. The results are generalized using the concept of hydrologic similarity, and they are presented in chart form. These charts can be used to determine the required stage-storage relationship for a detention basin and the size of the outlet structure. Sample applications are included to illustrate the use of the charts.

The Manning formula and the tractive force equation are combined and written in terms of dimensionless parameters. Predetermined solutions to this equation have been obtained and presented in chart form. Also, a mathematical expression is obtained that approximates the chart to determine the channel width explicitly.Key words: open channel, design, tractive force, erodible, shear stress.

A design aid is presented to size detention basins and outlet facilities for removal of particulate pollutants from storm runoff. The single‐design‐event approach is employed. The basins that are sized using the proposed method detain the runoff for a specified period of time to achieve the desired level of treatment. At the same time, the basins empty within a specified time period before the next design runoff event occurs. The method is based on the reservoir‐routing technique, which couples the hydrologic storage equation with an expression describing the hydraulics of the outlet structure. Orifice‐ and weir‐type outlet structures are considered. The equations are written in dimensionless form and solved using a finite‐difference computer model. The numerical results obtained in terms of the governing dimensionless parameters represent predetermined solutions to the reservoir‐routing problem. The results are generalized based on the concept of hydrologic similarity, and presented in chart form. As ill...

A generalized chart is presented to determine the spread in composite gutters given the gutter discharge. The use of this chart eliminates the tedious trial-and-error calculations to determine the spread in routine pavement drainage problems. The chart is also different from those available in the literature in the sense that it is limited neither to a specific unit system nor to specific gutter dimensions. The use of the chart is demonstrated through a practical application.

A desktop method is presented to analyze or size detention ponds and outlet facilities. Different initial conditions are allowed. When used for design purposes, the method determines the size of the outlet facility for a given pond. However, if the pond is inadequate to meet the design criteria set, the method determines the required stage‐storage relationship. The method is based on the usual reservoir‐routing technique that couples the hydrologic‐storage equation with an expression describing the flow through the outlet structure. The equations are rearranged in terms of several dimensionless parameters. A computer model is used to solve the governing equation using a finite difference scheme. The numerical results obtained in terms of systematically chosen combinations of the governing dimensionless parameters are generalized based on the concept of similarity. The generalized results are presented in chart form. Sample applications of these charts are illustrated.

Örgütsel çatısma, isletmelerde bireyler ve grupların birlikte çalısma sorunlarındankaynaklanan ve normal faaliyetlerin durmasına veya karısmasına neden olan olaylardır.Tarih boyunca hem sosyal, hem de biçimsel yapılarda, kısacası bireylerin oldugu herortamda çatısma yasanmıstır. Bu çalısmada çatısma kavramı yönetim bilimi çerçevesindeele alınmakta ve isletme örgütleri düzeyinde incelenmektedir.Çatısma, örgütte farklı sorumluluk anlayısı, egitim ve bakıs açısına sahipçalısanların isbirligi içersinde çalısma zorunlulugunun kaçınılmaz sonucudur. Çatısmaseviyesinin optimal düzeyde olması, örgüt performansını arttırıcı etkide bulunmaktadır.nsanları yeni yaklasımlara yönlendirmek, bireylerin motivasyonunu arttırmak gibiolumlu etkilerinin yanında, çatısan tarafların zihinsel ve bedensel saglıgını olumsuzetkilemek, isletmeyi hedeflerinden uzaklastırmak gibi olumsuz etkileri de bulunmaktadır.Tez çalısması dört bölümden olusmaktadır; Birinci bölümde, çatısma kavramınınfarklı bakıs açılarına göre yapılan tanımlarına yer verilerek, çatısmanın kavramsal birçerçevesi olusturulmaya çalısılmaktadır. Bunun yanında örgütsel çatısmanın zamaniçinde nasıl kabul görüp degerlendirildigi, çatısmaya karsı yönetim tarzlarınınyaklasımlarına, çatısmanın hangi asamalardan geçerek olustuguna, çatısmanın türlerineve isletmelerde çatısmalara neden olan etkenlere yer verilmektedir. kinci bölümdeörgütsel çatısmanın nedenleri, türleri ve sonuçları ele alınmaktadır. Üçüncü bölümde iseörgütsel çatısma yönetimine ve çatısmayı çözümleme yaklasımlarına yer verilmektedir.Buna göre çatısma yönetiminin süreçleri, çatısmayı çözümleme teknikleri ve türleriayrıntılı olarak ele alınmaktadır. Dördüncü bölümde ise stanbul'daki KOB boyutundakitekstil isletmelerinde, yapılan anket çalısmasının degerlendirmesine yer verilmektedir.Bu kısımdaki uygulama çalısması ile isletmelerde çalısanların is yerlerindeki çatısmalarayaklasımlarını degerlendirerek, literatürde anlatılanlarla karsılastırılmasına yerverilmektedir. The conflict of organization emerges from indivudual?s and group?s problems that areabout working with together. This causes to become confused or stop normal activities.During the history; people faced with conflicts in which were both social structure and formalstructure. Shortly in every situation. For this reason ;conflict concerned about lots ofdiciplines. The concept of conflict was taken into consideration at science frame and wasexamined on level of industry organization.Conflict is a result from workers who have different responsibility comprehensiondifferent education and view point,have to study with together or have to do cooperatively. Ifthe conflict level is optimal level, performances of organization increase. Conflicts have gotsome positive effects on people such as increasing of motivation,orientating at new approach;on the other hand conflicts have some negative effects on people such as taking away aims ofindustry, affecting bady mentally or physically.Thesis occurs from four different part. At first section/part :A conceptual frame isbeing tried to occur by making description that depends o different view points. Furthermore;how the conflict of organization was received ?the approaches of administration according tothe conflict how the conflicts occured. Conflicts? species and which factors can causeconflicts between industry workers are brought about at the second part. At the third part ofthesis :organizational conflicts? approaches and approaches of solutions are made to present.According to this part, solution? tecnique, species and process of administration aredetermined with a detailed way. At the fourth part: investigations? assessments which aremade in textile industries are explained. The textile industries that are KOB dimension instanbul. At this part, workers? approaches to the conflicts and applications? studies areevaluated and also comparisons between literature and these are explained. 181

A physical experiment from the undergraduate thermo-fluids laboratory titled "Venturimeter as a flow measuring device" has been chosen for its mapping into the virtual domain, as a computer-based experiment. The virtual experiment described in the present study, combines three unique aspects simultaneously: use of computer generated (virtual) data to recreate the physical phenomenon, virtual experimentation and measurement on a computer screen, and coupling of the virtual experiment with the LabVIEW software to introduce students to digital data acquisition and analysis. The proposed multi-media module has three sub-modules namely, the physical sub-module, the experimental details sub-module, and the virtual experiment sub-module, for introducing students to physical system configuration, experimental procedure, and detailed instructions for conducting virtual experimentation, data acquisition and analysis. The proposed module is expected to impact the development of virtual engineering laboratories for Web-based distance learning undergraduate engineering programs.

The original Horton equation is valid only if the rate of rainfall is always higher than the infiltration capacity of the soil throughout a rainfall-infiltration process. This technical note presents a modified Horton equation that expresses the soil infiltration capacity as a function of the amount of water that has already infiltrated into the soil. The modified equation is derived mathematically by combining the original and the integrated forms of the Horton equation. Therefore, the original Horton parameters are maintained in the modified equation. The modified and the original equations will give the same results when the assumptions of the original equation are valid. The advantage of the modified equation is that it can be used regardless of whether the rate of rainfall is greater than or less than the infiltration capacity. The technical note also includes expressions for the ponding time, and the amount of infiltration until ponding occurs.

The Manning roughness factor varies with the hydraulic radius in grass-lined channels. The functional relationship between the roughness factor and the hydraulic radius is highly nonlinear. This necessitates a lengthy and tedious trial-and-error method to solve the Manning formula in the different stages of the traditional design procedures for grass-lined channels. Various charts are presented in this technical note that can be used in designing grass-lined channels without a need for trial-and-error. The charts were developed using predetermined solutions to the Manning formula. They are presented in terms of dimensionless parameters and can be employed with any consistent unit system. The use of the charts is demonstrated through an example.

A nonlinear diffusion-wave model is developed for routing of floods in dendritic open-channel networks. The model considers backwater effects from both upstream and downstream ends of a channel. An overlapping-segment technique is adopted to decompose the network. The nonlinear algebraic finite-difference equations are solved through a special formulation of tridiagonal banded matrices. Comparison of the results of the proposed model to those of the dynamic-wave and nonlinear kinematic wave models indicates that the proposed model is nearly as accurate as, and computationally much cheaper, than the dynamic-wave model. It is computationally as inexpensive but more accurate than the nonlinear kinematic-wave model.

A desk-top method is presented to size detention ponds and the outlet facilities for multiple return periods. The method is based on the usual reservoir routing technique, which couples the hydrologic storage equation with those describing flow through the outlet structures. The equations are rearranged in terms of several dimensionless parameters. A computer model is employed to solve the governing equations using a finite difference scheme. The results obtained for carefully chosen combinations of the dimensionless parameters are generalized based on the concept of similarity. They are presented in chart form. These charts can be used directly, i.e., without a lengthy trial-and-error routing procedure, to size a detention pond that satisfies a set of design criteria requiring the control of runoff for at least three return periods. The use of the design charts are illustrated through a sample application.

A new interpretation is given for the rational formula in view of a mathematical model founded on the kinematic overland flow and Green and Ampt infiltration equations. The potential variability of the runoff coefficient with various rainfall and basin characteristics is demonstrated. However, using the concept of hydrologic similarity, it is possible to predict the runoff coefficient in terms of several physically-based non dimensional parameters for homogeneous planar, rectangular basins.

Soil properties have profound effects on overland flows over porous media. These effects are investigated by using a surface-subsurface flow conjunctive simulation model which solves the Saint- Venant equations for the overland flow and Richards' equation for the two-dimensional unsaturated and saturated porous medium flow. Guided by a dimensional analysis, four soil properties are studied, namely, porosity, vertical and horizontal saturated hydraulic conductivities, and unsaturated soil hydraulic characteristics which is expressed in two pairs of parameters describing the relationships between the degree of saturation and suction pressure, and between the relative conductivity and suction pressure, respectively. The results confirm the common belief that overland flow increases for decreasing soil porosity or saturated conductivity while the infiltration into the soil decreases. The effect of the ratio between horizontal and vertical saturated conductivity is insignificant, indicating the soil anisotropi...

A desk-top method is presented to predict the maximum runoff from pavement-gutter systems produced by temporally nonuniform rainfalls. The method is founded on the kinematic-wave solutions of the pavement and gutter flows. The governing equations are written in terms of three physically based nondimensional parameters. For a specified time pattern of rainfall intensity, the constant values of these parameters imply hydraulic similarity of an infinite number of different pavement-flow-gutter-flow situations. An implicit finite-difference technique is employed to solve the governing equations. The mathematical model is verified using a set of existing experimental data. Based on the concept of hydraulic similarity, a group of charts is developed to predict peak gutter-flow rates that are produced by triangular and Huff first-quartile-point rainfalls. The use of these charts is shown by a practical applications section. Similar charts can be developed for other types of rainfall hyetographs.

The capacity of a storm sewer system with a submerged outlet is affected by the downstream boundary condition, i.e., by the water level submerging the system outlet. Thus, uncertainties resulting from the randomness of the downstream water level and the rainfall events exist in the design of storm sewer systems with submerged outlets. A dynamic risk model is proposed in this paper to estimate the composite risk involved in such a system considering both the hydrologic and hydraulic uncertainties. For a simple hypothetical situation, a comparison of the composite risk and the conventional hydrologic risk is presented for different service lifes of the system.

A physically based mathematical model is presented for the process of pollutant washoff by overland flow on impervious surfaces. The model is based on the kinematic overland flow and convective pollutant transport equations. The pollutant detachment rate at any point along a surface is assumed to be proportional to the overland flow bottom shear stress and the amount of the pollutant on the surface. The constant of proportionality depends only on the pollutant characteristics, and therefore it can be treated as a calibration parameter insensitive to changes in the hydrologic conditions of the basin. The governing equations are written in dimensionless form, and are solved using an implicit finite difference scheme. The mathematical model is verified with a set of published experimental data. Based on the concept of hydraulic similarity, the results of the model are generalized and presented in chart form.