College of Engineering Project Reports
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Item type: Item , VSAT Data Network(Honolulu, Hawaii: PRIISM, Pacific Research Institute for Information Systems and Management, 1990) Abramson, NormanTwo general methods have been used to provide random access packet communications in Very Small Aperture (VSAT) data networks – Spread Spectrum (or CDMA) and ALOHA. In this paper we review the use of satellite channels for such networks and discuss certain basics aspects of the architecture of VSAT data networks. Although Spread Spectrum and ALOHA have different origins and are sometimes represented as competing technologies, they can in fact be characterized as different ways of viewing the same low dimensional signals in a high dimensional signal space. After a brief introduction to the architecture of VSAT networks we show how a simple linear transformation of conventional ALOHA packets leads to signals identical in all respects to the most common form of Spread Spectrum signals. We call the result of this transformation Spread ALOHA.
There are two practical consequences of this theoretical result. First, for the case of small earth stations it is not possible to find an access technique with a higher throughput than Spread ALOHA. Second, the use of different spreading sequences for different users in a packet network using Spread Spectrum is not necessary for user separation.
Item type: Item , Spread ALOHA for VSATs(Honolulu, Hawaii: PRIISM, Pacific Research Institute for Information Systems and Management, 1986) Abramson, NormanSpread ALOHA is a multiple access protocol using conventional ALOHA packets spread in time, so that the packet contention interval at the output of the packet receiver is not increased. Packets transmitted using a Spread ALOHA protocol can overlap in the physical channel with high probability, but still be separated at the output of a matched filter, so that the probability of overlap at the receiver output is low. Spread ALOHA operation of a data channel combines several characteristics of ALOHA channels and Spread Spectrum channels. The use of Spread ALOHA can achieve certain efficiencies and simplicities of operation which are not possible in conventional ALOHA channels or conventional Spread Spectrum channels. In particular, for the case of a large number of small earth stations accessing a single satellite transponder in a data network, no signaling technique is possible which can achieve a higher average data throughput for a given average power and a given bandwidth than Spread ALOHA.
This report is preliminary only. It contains an explanation of the basic elements of a Spread ALOHA channel together with some notational material which serves to emphasize the connection between Spread ALOHA, conventional Spread Spectrum and algebraic coding theory. A more detailed report will be provided at a later date.
Item type: Item , Research proposal to the Geothermal Division Energy Research and Development Administration(Hawaii Geothermal Project, University of Hawaii at Manoa, 1976-05-17) Shupe, JohnAddendum to proposal submitted May 17, 1976. The purpose of the funds requested in this proposal is to provide support with which to complete analysis and interpretation of the data and, through comparison with actual subsurface conditions, develop correlations on the reliability of the various methods of prediction. We also propose a limited number of field experiments designed to assist in the understanding of the reservoir dynamics. A synthesis of all pertinent data--from geosciences, from mathematical modeling, from drilling, from welltesting-- will contribute to a more complete understanding of the geothermal regime associated with this well.Item type: Item , Research proposal submitted to the National Science Foundation, Research Applied to National Needs (RANN), Advanced Energy Research and Technology(University of Hawaii at Manoa, College of Engineering, 1974) Shupe, JohnHawaii Geothermal Project - Phase II. The Hawaii Geothermal Project was established to focus the resources of the State and the University of Hawa-ii on a coordinated research effort leading to the development of geothermal power on the Big Island of Hawaii. Phase I of the Project was initiated in the summer of 1973 with a $252,000 grant from NSF-RANN, supplemented by $100,000 each from the State and the County of Hawaii. This $452,000 budget was organized into a multidisciplinary research effort in the following program areas: (1) Geophysical - exploratory surveys to define the most favorable areas for geothermal investigations; (2) Engineering - analytical models to assist in interpretation of geophysical results, and studies on energy recovery from hot brine; and (3) Socioeconomic- legal and regulatory aspects of ownership and administration of geothermal resources, and economic planning studies on the impact of geothermal power.Item type: Item , Research proposal submitted to the National Science Foundation, Research Applied to National Needs (RANN)(University of Hawaii at Manoa, 1973)Hawaii is generously endowed with many forms of natural energy--wind, wave, solar, and geothermal--all potentially low-pollution power sources. This proposal requests RANN funding to assist in developing that resource which appears to have the greatest potential for meeting the State's expanding power requirements--geothermal energy. In honor of Pele, the Hawaiian Goddess of Fire and resident of island volcanoes, the program is entitled Pele Energy Laboratory Experiments. The PELE Project involves an interdisciplinary team of fifty-four researchers from throughout the University of Hawaii System who, in collaboration with a distinguished group of advisors and consultants, will engage in thirty-eight separate research tasks related to geothermal power. These scientific investigations are grouped into three programs: a) Geophysical, b) Engineering, and c) Environmental and Socioeconomic; and include both short- and long-range research studies on the identification, generation, and utilization of geothermal energy. A secondary objective of the PELE Project is to provide the geophysical data and engineering technology to assist in the early development of geothermal power on the Big Island of Hawaii. Consequently, the drilling of deep test holes and planning for construction of a prototype geothermal power plant are included in this proposal. The prototype plant, in addition to providing essential data on the reservoir characteristics of the geothermal field, will serve as an observation and working laboratory for engineers and scientists from throughout the world. This project has the interest and support of both State and County governments, as well as the private utilities on the three major islands. The potential is excellent for involving education, private interests, and government at the local, state and federal levels in this significant research project for expanding the technology base on geothermal energy and for developing a low-pollution power source for Hawaii and the Nation.Item type: Item , Hawaii Natural Energy Institute daily drilling report from 11-02-90 to 02-27-91(Hawaii Natural Energy Institute, University of Hawaii at Manoa, 1991) Hawaii Natural Energy Institute, University of Hawaii at ManoaInformation includes hole number, date, depth, time, personnel involved, and additional information.Item type: Item , Reservoir assessment of the Puna Geothermal Field, Island of Hawaii(GeothermEx, Inc., 1989-07) GeothermEx, Inc.The first step in assessing a geothermal resource is to develop a hydrogeologic model which defines the three-dimensional distributions of temperature and pressure and relates these distributions to the geologic structures that control the flow of thermal fluid. An assessment of the available energy beneath the lease will be based on the temperature distribution, and the drilling plan will be based on the permeability distribution inferred from the hydrogeologic model. Surface geology, interpreted from aerial photographs, and subsurface geology, inferred from geophysical data, are described in Section 2 of this report. Subsurface temperature and pressure distributions are described in Sections 3.1 through 3.3, and section 3.4 summarizes the hydrogeological model developed from interpreting the temperature and pressure distribution patterns in relation to the geology described in Section 2. Section 4 summarizes the results of well tests, including the chemistry of the thermal fluid. Section 5 describes the volumetric estimate of reserves.Item type: Item , Performance matching and predicting of a geothermal reservoir(University of Hawaii at Manoa, 1976-08) Seki, Arthur S.The initial conditions (physical and chemical state) of a geothermal reservoir and its fluids are important information needed in geothermal reservoir engineering for determining the future productivity of the reservoir. An optimization scheme was employed to minimize the least squares function and determine the optimum initial conditions. Using the mass, energy, and volumetric balance equations, the initial param-Beters were obtained by matching the production data plot of average reservoir pressure versus cumulative mass produced for a compressed liquid, saturated liquid-steam, and superheated steam reservoir. Once a good curve match was attained, the performance projection of the geothermal reservoir was made at different production rates. A successful curve match was found to be highly dependent on the constraints chosen in the optimization scheme. Mass influx, as well as porosity also proved to be an influencing factor in the determination of the initial conditions.Item type: Item , Computer performance matching and prediction of geothermal reservoirs : technical report no. 22(University of Hawaii at Manoa, 1977-03-14) Seki, Arthur S.; Chen, Bill H.; Takahashi, Patrick K.The initial conditions (physical and chemical state) of a geothermal reservoir and its fluids are important information needed in geothermal reservoir engineering for determining the future productivity of the reservoir. An optimization scheme was employed to minimize the least squares function and determine the optimum initial conditions. Using the mass, energy, and volumetric balance equations, the initial parameters were obtained by matching the production data plot of average reservoir pressure versus cumulative mass produced for a compressed liquid, saturated liquid-steam, and superheated steam reservoir. Once a good curve match was attained, the performance projection of the geothermal reservoir was made at different production rates. A successful curve match was found to be highly dependent on the constraints chosen in the optimization scheme. Mass influx, as well as porosity also proved to be an influencing factor in the determination of the initial conditions. The computer prediction model is presently being used to assess reservoir conditions for the Hawaii Geothermal Project Well A, believed to be the hottest producing geothermal well in the world.Item type: Item , HNEI's documents for SOH-3(Hawaii Natural Energy Institute, University of Hawaii at Manoa, 1990-09) Hawaii Natural Energy Institute, University of Hawaii at ManoaFrom the cover letter: "The University of Hawaii formally requests your approval to initiate drilling activities for a Scientific Observation Hole (SOH 3) in the area (TMK) 1-2-10:03) under Conservation District Use Permit (HA 12/20/85-1830) issued to the Estate of James Campbell. SOH 3 is to be located on the True/Mid-Pacific alternate drill site No. 2, about 3,000 feet north-north-west of their present drilling operations. Access to this drill site will be by a new road starting from True/Mid-Pacific's drill site. Only a portion (approximately a quarter acre plus access road around the drill site) of the True/Mid-pacific alternate drillsite No. 2 will be grubbed and graded for our operations."Item type: Item , Chemistry, scale, and performance of the Hawaii Geothermal Project-A plant(Hawaii Electric Light Company, Inc., 1985-12) Baughman, E.C.; Uemura, Roy T.The objective of this study was to determine the effects of scale, corrosion, and erosion of the geothermal resource on HGP-A Geothermal Wellhead Power Plant. Analysis of the fluid chemistry was made to interpret the cause of corrosion and scale deposition in the brine and steam systems. It was found that metal sulfide scale formation occurred in the steam system and silica type scale formation in the brine system. The rate of scale deposition was strongly influenced by thechemical conditions in those systems. Although scale and corrosion did occur in the plant piping systems and equipment, they did not appreciably affect the performance of the plant. The results of this study will make the utilities more aware of the effects of geothermal fluid chemistry on scale deposition and corrosion which may increase plant efficiency and reduce maintenance of future plants.Item type: Item , An archaelogical reconnaissance survey in the geothermal resource subzone of Upper Kamaili, Kehena and Kikala, Puna, Hawaii(University of Hawaii at Hilo, 1989-09) Bonk, William J.In August of 1989, Mr. Art Seki from the Hawaii Natural Energy Institute, University of Hawaii at Manoa contacted the writer of this report with a request for an archaeological reconnaissance survey of a geothermal well site adjacent to land I had already surveyed in 1987 (Bonk. 1988). At the time of the request, I had just agreed to take on further investigation along the roadway and at the terminus and therefore was willing to examine this fairly small additional area, for I knew I would be in the region. As with the previously examined roadway, this plot is on property of the Estate of James Campbell in the Puna District, on the island of Hawaii. Specifically, the area investigated is on the north-east rift of Kilauea, south of Kaohe Homesteads (See map 1) and is in the uplands of Kamaili, Kehena, and Kikala, Puna. Through the office of Mr. Nobuchila Santo of Island Survey, Inc., I received pertinent information and copies of a plan showing the location of the project area. On September 9th I carried out the field work for this report with the able assistance of my son, Ken.Item type: Item , Item type: Item , A geothermal electric and nonelectric research facility utilizing the HGP-A well on the island of Hawaii : a proposal to Energy Research and Development Administration, Division of Geothermal Research(Research Corporation of the University of Hawaii, 1977-04-06)Technical. This proposal to the Geothermal Division of ERDA for a geothermal research station on the island of Hawaii (Figure 2-1) is directed toward the utilization of geothermal resources for research that will benefit the entire geothermal community. Project support, to date, has been ERDA, the State and County of Hawaii, the National Science Foundation, Water Resources International, Hawaiian Electric Company, and other public and private groups. ERDA has provided 60% of the resources required to drill and test a 6450-feet-deep geothermal well (designated HGP-A) that produces high quality steam at a rate, temperature, and pressure equivalent to approximately 4 megawatts of electrical power.Item type: Item , Geothermal guidebook : prepared for the Hawaii Legislature 1980 geothermal policy review(National Conference of State Legislatures (NCSL), Geothermal Project, 1980-06)The National Conference of State Legislatures (NCSL) Geothermal Project has been invited by the Hawaii Legislature to assist in a review of geothermal policy issues. This Geothermal Guidebook is a basic research document of the Project. It describes what geothermal resources are and how they may be developed. The appendices contain additional detailed background material including a glossary and bibliography. Specific sections on Hawaii's geothermal potential. statutes and regulations, were prepared for this document. The bulk of the Guidebook is a discussion of generic policy concerns relating to geothermal energy. This section provides the background analysis necessary to understand the particular issues of concern in Hawaii. These issues have been previously identified and policy recommendations have been made for the 1980 session. These recommendations are being reviewed for possible introduction in the 1981 session.Item type: Item , Hawaii Geothermal Project : Engineering program : quarterly report no. 1(Hawaii Geothermal Project, University of Hawaii at Manoa, 1973-09) Augustus, Joseph; Chai, Hi Chang; Chen, Bill H.; Cheng, Ping; Chou, James C.S.; Kihara, Deane H.; Lau, Kah Hie; Takahashi, Patrick K.; Yuen, Paul C.The objectives of the Engineering Program are (1) applied research in problem areas related to the extraction of energy from geothermal resources, and (2) planning, design, and specification of a research-oriented, environmentally acceptable geothermal power plant. Work is progressing currently on four of the tasks originally proposed: Task 3.1 Well Test Analysis Task 3.2 Ghyben-Herzberg Lens Dynamics Task 3.6.1 Heat Exchanqer and Binary-Fluid Cycle Design Task 3.6.2 Optimal Hot Brine Plant Design This report summarizes the timetable (A) for each task, the progress made to date (B), and the future work planned (C).Item type: Item , Geothermal energy in Hawaii : present and future(Hawaii Geothermal Project, University of Hawaii at Manoa, 1978) Shupe, John W.; Yuen, Paul C.Discussed the development of Hawaii Geothermal Project, from Phase I to Phase IV, including budget summary for HGP-A, and preliminary test results and analyses for HGP-A geothermal well and Kapoho geothermal reservoir. It also discussed the future of geothermal energy in Hawaii. This paper is presented to the Circum-Pacific Energy and Mineral Resources Conference in Honolulu, Hawaii, in August 2, 1978.Item type: Item , Hawaii Geothermal Project Engineering Program : phase I report January, 1975(Hawaii Geothermal Project, University of Hawaii at Manoa, 1975-01) Chai, Hi Chang; Chen, Bill H.; Cheng, Ping; Chou, James C.S.; Kihara, Deane H.; Lau, Kah Hie; Lau, L. Stephen; Takahashi, Patrick K.; Yuen, Paul C.The principal objectives of the Engineering Program are 1) to solve important problems related to the extraction of energy from geothermal resources (Task 3.1), and 2) to plan and design an environmentally acceptable geothermal power plant suitable for Hawaiian geothermal reservoirs (Task 3.6). Research during the past period has been devoted primarily to the theoretical and physical modelling of geothermal reservoirs, preparation for the engineering testing of wells to be drilled on the island of Hawaii, and studies of various methods of converting the heat energy in a geothermal reservoir to electrical energy. Results of the research effort have been reported in five quarterly progress reports and technical memorandums and reports.Item type: Item , Geothermal reservoir and well test analysis : a literature survey : technical memorandum no. 2(University of Hawaii at Hilo, 1974-09) Chen, Bill H.This report deals primarily with the analysis of the required parameters, focusing on the various pressure measurements and anayisis techniques. It also surveys the material - heat balance equations essential for the establishment of a reservoir model for performance matching prediction. This report also assumes that we have a geothermal reservoir with little or no net heat transfer. With this assumption one can regard the geothermal reservoir as a reservoir with isothermal fluid flow. This is the same assumption used in developing pressure analysis techniques in a petroleum reservoir. Therefore, petroleum well test analysis techniques, with very little modification, can be utilized for geothermal reservoir analysis.Item type: Item , Warm water wells on the Island of Hawaii : technical memorandum #1 January 1, 1974(College of Engineering, University of Hawaii at Manoa, 1974-01) Shito, SusanA literature search on the location and other characteristics of wells producing 79°F (26°C) water or hotter on the island of Hawaii turned up one pertinent publication, THE INVENTORY OF BASIC WATER RESOURCES DATA: ISLAND OF HAWAII. According to this publication, five drilled wells meeting this requirement are located in the Puna and South Kohala districts. They produce water with temperatures ranging from 790F to 129°F (26°C to 54°C) with chloride contents of 254 ppm to 6200 ppm from elevations of 274 feet to 982.4 feet and static water levels of .56 to 5.24 feet. The diameters of these wells range from 10 inches to 15 inches. Tables and maps follow. Included are a drilled well index, well location maps, and water quality tables.