Digital Commons Network^™

Collaboration Among Municipal Water Providers: Meeting Metro Denver Water Demand, Lee Rozaklis

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

11 pages (includes color illustrations).

An Environmental Perspective On Collaboration In Large Ecosystem Restoration Processes, Daniel F. Luecke

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

13 pages (includes illustration).

Contains 3 pages of references.

A Western Slope Perspective: Endangered Species And Municipal Water, David C. Hallford

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

13 pages (includes 1 map).

Contains footnotes and 1 page of references.

Mathematical Description Of Air Cooling Using A Mining Diaphragm Cooler Taking Into Consideration The Condensation Of Water Vapour, Waclaw Dziunyński, Stanislaw Nawrat, Bernard Nowak, Janusz Roszkowski

U.S. Mine Ventilation Symposium

Taking into consideration the possibility of condensation of water vapour contained in air which flows through a diaphragm cooler, a mathematical model of space-time changes in air temperature, humidity, and also in the temperature of the heat exchanger and the cooling water in the cooler in question was created. In the mathematical description of air-cooling using the above-mentioned cooler two zones was identified. The first concerns the dry cooling of air, while within the second, the process of outdropping of water contained in the cooled air. Each of these zones has been described by applying a system of three partial …

Rapid Extinguishing Of Sponcom Fires In Underground Mines, Zygmunt Kajdasz, George Zieba

U.S. Mine Ventilation Symposium

The main purpose presented in this paper is to present active and passive methods to fight a sponcom fire. The active method uses an inert gas generator called the GAG while the passive method is through the use of ventilation software. In most sponcom situations a combination of these two methods results in rapid extinguishing of the overheated areas. The presented software allows for accurate and "real time" analysis of the ventilation network. Application of the GAG has been proven on many occasions as an effective means of large volumes of mine atmosphere.

Gob Spontaneous Combustion In A Fully Mechanized Long-Wall Top-Coal Caving Face, Jingcai Xu, Jun Deng, Xinghai Zhang, Xingming Guo, Fu Wen

U.S. Mine Ventilation Symposium

Geological conditions allow, underground coal mines in China tend to use comprehensively mechanized roof-coal caving technique in an effort to gain a higher degree of mechanization at coal faces as well as higher coal production rates. As a face advances, a large amount of coal will be left behind in its gob area which may experience a self-enhancing process of coal oxidation and heat accumulation, ultimately leading to open fire. Such a self-enhancing coal spontaneous combustion process is a significantly impeding mine safety and productivity. A sound mathematical model is an important step to predict the probability of spontaneous combustion …

A Comparison Of Air Leakage Prediction Techniques For Auxiliary Ventilation Ducting Systems, A. D. Stewart Gillies, Hsin Wei Wu

U.S. Mine Ventilation Symposium

This paper briefly reviews prediction techniques for determination of leakage and friction along auxiliary ventilation ducting systems. In order to compare various prediction techniques that have been developed over the past, a macroscopic investigation of air leakage and friction resistance of auxiliary ventilation ducting systems has been undertaken. Measurements were conducted on 450 and 915 mm diameter fabric ducting over 100 m duct length to determine frictional resistances and the extent of leakage. Due to the high degree of accuracy required and the large volume of data that needed to be collected, electronic pressure transducers were used with computer for …

Direct And Inverse Problem Of Diffusion With Simultaneous Linear Accumulation, Petko Ivanov Lalov

U.S. Mine Ventilation Symposium

Mine working contamination occurs when diffusion in a constant velocity medium is accompanied by a process of absorption and accumulation of the diffunding medium, as described by the generalized convective diffusion equation proposed by J.L. Litwiniszyn. The first part of this article discusses the problem of finding a solution to the integro-differential equation under study for defined initial and boundary conditions corresponding to working with a finite length (direct problem). The second part solves the problem of determining the coefficients of this equation by using the results of measurements of the contaminant concentration by sensors positioned along the working (inverse …

Method For Operative Prediction Of Sponcom Hazard In Gob Area, Michael Michaylov

U.S. Mine Ventilation Symposium

Expert systems for SPONCOM risk assessment ·are used for choosing suitable fire-proof mining systems and ventilation schemes. Some of them can even estimate the effectiveness of planned ventilation and specific anti-fire measures for SPONCON risk reduction as early as at the design phase. The method proposed herewith is appropriate for operative evaluation of SPONCM risk in gob areas for the following three phases during longwall development: design stope, the commencement of production, and during production. Data from mine and model experiments and statistical data for the actual coal seams serve as a basis for defining index of relative SPONCOM risk …

Table Of Contents, Multiple Authors

U.S. Mine Ventilation Symposium

No abstract provided.

Soul Of The Firm: Business As A Christian Calling, C. William Pollard

C. William Pollard Papers

Pollard delievered this speech at Business '99: An Outstanding Christian Calling, a symposium held by Calvin College (Grand Rapids, MI). In it he speaks of how a holistic focus on people is the bedrock of transforming work into a holy vocation.

Eastern Washington University Commencement Program, 1999, Eastern Washington University

Commencement Programs

Program for Eastern Washington University's spring commencement in 1999

Computer Simulation Of Climatic Conditions For Underground Automated Mines For Standard And Reduced Airflow Requirements, Julian Partyka, Stephen Hardcastle, Charles Kocsis

U.S. Mine Ventilation Symposium

This study demonstrates the importance of ventilation in an automated mine through climatic simulations. These have been performed on workings located at depths of 1000 m to 3000 m below surface in an underground metal mine. Each active working area employs either an electric or a diesel piece of equipment that has a full load power output of 100 kW to 200 kW. The airflows considered in the mining areas were standard full-flow conditions, i.e. 100% (6.5 m3/100 kW), and 125%, 75%, and 50% of full-flow. The analyses show, for instance, that a 100 kW electric machine can increase the …

A Mathematical Model Of Heat Transfer In Partially Insulated Airways In Deep, Frozen Ground Placer Mines, Sukumar Bandopadhyay, Hanguang Wu, Michael G. Nelson

U.S. Mine Ventilation Symposium

Large seasonal variations in the temperature of the ventilating air in mines in the arctic cause changes in the original thermal field through heat and mass exchanges between the air and the surrounding medium. These thermal interactions have major influence on climatic quality as well as on the stability of the mine openings. Thawing of walls and roof in mine airways can be reduced by various types of thermal-insulation. Application of thermal-insulation prevents deep thawing of the rockmass surrounding an airway. In this case, the mechanism of heat transfer around a frozen, underground airway would be much different. A model …

Modelling Of Gob Inertization With Nitrogen, Michael Michaylov, Elena Vlasseva

U.S. Mine Ventilation Symposium

The paper deals with a modelling of nitrogen distribution throughout gob so that the effect of inertization could be measured. The model takes into account flow transient character, methane liberation and different locations for nitrogen injection. Computer modelling, reflecting mathematical models is done by a specially created computer programme NITRO_ GOB, which allows dealing with different parameters of air leakage, of coal waste distribution as well as of gas picture in the gob before inertization. Effective evaluation of the most important parameters - injection place and nitrogen volume- on gob gas picture is illustrated under typical cross-section profiles of gas …

Genetic Algorithm Optimization Of A Large U.K. Coal Mine Ventilation Network, Zhi-Yuan Yang, I. S. Lowndes, B. Denby

U.S. Mine Ventilation Symposium

This paper reports on results of an application of a genetic algorithm to the optimisation of a large UK Coal Mine Ventilation Network. The genetic algorithm technique has been developed into a computer program for minimising the total network operating fan power costs. The application of booster fans may become an attractive alternative for ventilation engineers to provide an adequate supply of fresh air around the working areas in some deep and/or extensive mines. The objective of this research is to minimize the total power consumption of a ventilation system by determining the optimum combinations of (1) main fan and …

Characteristics Of Airborne Dust In The Return Airways Of The Mechanized Longwall Face, Tevfik Güyagüler, Sinan Keskin

U.S. Mine Ventilation Symposium

In this paper the results of a research study on the characterisation of airborne dust in the return airway of the mechanized longwall face at Middle Anatolian Lignite Mine, OAL are presented. Dust, temperature, moisture and air velocity measurements were carried out in the return airways of the fully mechanized longwalls. Then the analyses of results on real-time concentration data, mass concentration data, effect of moisture, heat and air velocity on dust concentration are made. It has been found that amount of dust in return airway is directly related to the face activities and to the amount of settled dust …

On-Off Intermittency In Stochastically Driven Electrohydrodynamic Convection In Nematics, Thomas John, Ralf Stannarius, Ulrich Behn

Mathematics - All Scholarship

We report on-off intermittency in electroconvection of nematic liquid crystals driven by a dichotomous stochastic electric voltage. With increasing voltage amplitude we observe laminar phases of undistorted director state interrupted by shorter bursts of spatially regular stripes. Near a critical value of the amplitude the distribution of the duration of laminar phases is governed over several decades by a power law with exponent -3/2. The experimental findings agree with simulations of the linearized electrohydrodynamic equations near the sample stability threshold.

Indian Water Rights And The Snake River Basin Adjudication, Peter C. Monson

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

19 pages (includes map).

Tmdl Implementation Under The Clean Water Act, Bruce Zander

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

17 pages (includes illustrations and maps).

Contains references.

Idaho's Snake River Basin Adjudication: A Window On Western Water Law, Jeffrey C. Fereday

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

34 pages.

Contains footnotes.

Priorities Of The States For Clean Water Act Reauthorization, J. David Holm

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

16 pages.

The Esa: Oil And Water?, Joseph L. Sax

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

4 pages.

Federal Water Rights In The Snake River Basin Adjudication, Michael A. Gheleta

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

34 pages (includes maps).

The Clean Water Action Plan, Sylvia V. Baca

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

3 pages.

Federal Facilitation Of Water Rights Negotiations In The West, Mike Connor

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

11 pages.

Wsu Board Of Trustees Meeting Minutes, June 10-11, 1999

Board of Trustees Minutes

Minutes from the Wright State University Board of Trustees Meeting held on June 10-11, 1999.

June 9, 1999 Cal Poly Report, Public Affairs Office

Cal Poly Report

No abstract provided.

Basin-Wide Adjudications In The West: What Works, What Doesn’T?, Ramsey L. Kropf

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

18 pages.

Contains 2 pages of references.

Do Basin-Wide Adjudications Work, For Tribes Or Anyone Else?, Reid Peyton Chambers

Strategies in Western Water Law and Policy: Courts, Coercion and Collaboration (Summer Conference, June 8-11)

3 pages.