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2012

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Articles 541 - 570 of 1093

Full-Text Articles in Civil and Environmental Engineering

Use Of Mill Certficates To Establish Material Properties In Testing Of Colf-Formed Steel Compoenents, Tim Stauffer, Paul Mcentee Apr 2012

Use Of Mill Certficates To Establish Material Properties In Testing Of Colf-Formed Steel Compoenents, Tim Stauffer, Paul Mcentee

CCFSS Library (1939 - present)

Testing is often used to establish the available strength of cold-formed steel components. The evaluation of this test data requires adjustment based on the material properties of the tested components to account for values that exceed the minimum specified values. Currently, it is required that this adjustment be based on samples taken from the tested specimen or the flat sheet used to form the test specimen. However, in many cases it is not practical to obtain these samples. Instead, it is desired to permit an alternate that allows the use of mechanical properties reported by the steel supplier. The purpose …


Science And Society: The Role Of Long-Term Studies In Environmental Stewardship, Charles T. Driscoll, Kathleen F. Lambert, F. Stuart Chapin, David J. Nowake, Thomas A. Spies, Frederick J. Swanson, David B. Kittredge, Clarisse M. Hart Apr 2012

Science And Society: The Role Of Long-Term Studies In Environmental Stewardship, Charles T. Driscoll, Kathleen F. Lambert, F. Stuart Chapin, David J. Nowake, Thomas A. Spies, Frederick J. Swanson, David B. Kittredge, Clarisse M. Hart

Civil and Environmental Engineering - All Scholarship

Long-term research should play a crucial role in addressing grand challenges in environmental stewardship. We examine the efforts of five Long Term Ecological Research Network sites to enhance policy, management, and conservation decisions for forest ecosystems. In these case studies, we explore the approaches used to inform policy on atmospheric deposition, public land management, land conservation, and urban forestry, including decisionmaker engagement and integration of local knowledge, application of models to analyze the potential consequences of policy and management decisions, and adaptive management to generate new knowledge and incorporate it into decisionmaking. Efforts to enhance the role of long-term research …


Watershed-Level Responses To Calcium Silicate Treatment In A Northern Hardwood Forest, Youngil Cho, Charles T. Driscoll, Chris E. Johnson, Joel D. Blum, Timothy J. Fahey Apr 2012

Watershed-Level Responses To Calcium Silicate Treatment In A Northern Hardwood Forest, Youngil Cho, Charles T. Driscoll, Chris E. Johnson, Joel D. Blum, Timothy J. Fahey

Civil and Environmental Engineering - All Scholarship

Watershed 1 (W1) at the Hubbard Brook Experimental Forest in New Hampshire, with chronically low pH and acid neutralizing capacity (ANC) in surface water, was experimentally treated with calcium silicate (CaSiO3; wollastonite) in October 1999 to assess the role of calcium (Ca) supply in the structure and function of base-poor forest ecosystems. Wollastonite addition significantly increased the concentrations and fluxes of Ca, dissolved silica (Si), and ANC and decreased the concentrations and fluxes of inorganic monomeric Al (Ali) and hydrogen ion (H+) in both soil solution and stream water in all sub-watersheds of W1. …


Assessing Impermeable Surface Area Impacts On Modeling: Implications For The Combined Sewer Overflow Long Term Control Plan In Omaha, Nebraska, Andrew D. Szatko Apr 2012

Assessing Impermeable Surface Area Impacts On Modeling: Implications For The Combined Sewer Overflow Long Term Control Plan In Omaha, Nebraska, Andrew D. Szatko

Community and Regional Planning Program: Professional Projects

The report looks at assessing the accuracy of estimating impervious surface areas (ISAs) by zoning code, the method utilized by the City of Omaha, Nebraska. A 101 acre subcatchment had all ISAs manually digitized and compared the actual with the estimated value. The subcatchment was then modeled with 10 percent decreases of ISAs to establish the relationship with peak flow rates and total volume in the combined sewer service area. The results show a significant relationship between the two that may provide insights into a new approach to manage CSO events with the integration of green infrastructure.


Mathematical Modeling Of Pipeline Features For Robotic Inspection, Yang Gao Apr 2012

Mathematical Modeling Of Pipeline Features For Robotic Inspection, Yang Gao

Doctoral Dissertations

Underground pipeline systems play an indispensable role in transporting liquids in both developed and developing countries. The associated social and economic cost to repair a pipe upon abrupt failure is often unacceptable. Regular inspection is a preventative action that aims to monitor pipe conditions, catch abnormalities and reduce the chance of undesirable surprises. Robots with CCTV video cameras have been used for decades to inspect pipelines, yielding only qualitative information. It is becoming necessary and preferable for municipalities, project managers and engineers to also quantify the 3-D geometry of underground pipe networks. Existing robots equipped specialized hardware and software algorithms …


Fertilization Effects On The Ecohydrology Of A Southern California Annual Grassland, Anthony J. Parolari, Michael L. Goulden, Rafael L. Bras Apr 2012

Fertilization Effects On The Ecohydrology Of A Southern California Annual Grassland, Anthony J. Parolari, Michael L. Goulden, Rafael L. Bras

Civil and Environmental Engineering Faculty Research and Publications

Nitrogen limits leaf gas exchange, canopy development, and evapotranspiration in many ecosystems. In dryland ecosystems, it is unclear whether increased anthropogenic nitrogen inputs alter the widely recognized dominance of water and energy constraints on ecohydrology. We use observations from a factorial irrigation and fertilization experiment in a nitrogen-limited southern California annual grassland to explore this hypothesis. Our analysis shows growing season soil moisture and canopy-scale water vapor conductance are equivalent in control and fertilized plots. This consistency arises as fertilization-induced increases in leaf area index (LAI) are offset by reduced leaf area-based stomatal conductance, gs. We interpret this as evidence …


Estimating Connecticut Stream Temperatures Using Predictive Models, Erik Carlson Apr 2012

Estimating Connecticut Stream Temperatures Using Predictive Models, Erik Carlson

Honors Theses and Capstones

The Connecticut Department of Energy and Environmental Protection (CT DEEP) seeks to better classify their streams into thermal regimes (cold, cold transitional, warm transitional, and warm water). A prediction model was created based upon physical characteristics such that CT DEEP could classify streams into thermal regimes based upon the parameters described in Lyons et al. 2009 and compare them to their own classification system. Accurately classifying these thermal regimes determines the environmental protection provided to a stream as well as the potential for establishing fisheries.


Arched Bridges, Lily Beyer Apr 2012

Arched Bridges, Lily Beyer

Honors Theses and Capstones

An exploration of arched bridges through history. Influence lines for three-pinned and two-pinned arches for moment and axial load are developed. An analysis of the Chesterfield Brattleboro Bridge is included


Corrosion Rate Of Carbon Steel For Flowline And Pipeline As Transmission Pipe In Natural Gas Production With Co2 Content, Andi Rustandi, Muhammad Adyutatama, Enriko Fadly, Norman Subekti Apr 2012

Corrosion Rate Of Carbon Steel For Flowline And Pipeline As Transmission Pipe In Natural Gas Production With Co2 Content, Andi Rustandi, Muhammad Adyutatama, Enriko Fadly, Norman Subekti

Makara Journal of Technology

The purpose of this research is to investigate the corrosion rate of carbon steel as flowline and pipeline in natural gas production with CO2 content. The influence of variety of conditions that represent the actual conditions in practice such as CO2 partial pressure and solution composition, particularly NaCl percentage were performed. Research conducted by polarization test and simulation methods using PREDICTTM software. The result of this research is used to illustrate the level of corrosion rate of typical carbon steel i.e. API 5L X-52 occurred in natural gas pipelines due to the effect of dissolved CO2. From the experiments obtained …


Speed Limit Recommendation In Vicinity Of Signalized High-Speed Intersection, Anuj Sharma, Laurence Rilett, Zifeng Wu, Shefang Wang Apr 2012

Speed Limit Recommendation In Vicinity Of Signalized High-Speed Intersection, Anuj Sharma, Laurence Rilett, Zifeng Wu, Shefang Wang

Nebraska Department of Transportation: Research Reports

No abstract provided.


Anaerobic Co-Digestion For Enhanced Renewable Energy And Green House Gas Emission Reduction, Navaneethan Navaratnam Apr 2012

Anaerobic Co-Digestion For Enhanced Renewable Energy And Green House Gas Emission Reduction, Navaneethan Navaratnam

Dissertations (1934 -)

The need to develop renewable energy is important for replacing fossil fuel, which is limited in quantity and also tends to increase in price over time. The addition of high strength organic wastes in municipal anaerobic digesters is growing and tends to increase renewable energy production. In addition, conversion of wastes to energy significantly reduces uncontrolled greenhouse gas emissions. Co-digestion of municipal sludge with any combination of wastes can result in synergistic, antagonistic or neutral outcomes. The objectives of this study were to identify potential co-digestates, determine synergistic, antagonistic and neutral effects, determine economic benefits, quantify performance of bench scale …


Concurrent Engineering Of Tolerance Synthesis And Process Selection For Products With Multiple Quality Characteristcs Considering Process Capability, Mohamad Imron Mustajib Apr 2012

Concurrent Engineering Of Tolerance Synthesis And Process Selection For Products With Multiple Quality Characteristcs Considering Process Capability, Mohamad Imron Mustajib

Makara Journal of Technology

The existences of variances that are very difficult to be removed from manufacturing processes provide significance of tolerance to the product quality characteristics target of customer functional requirement. Furthermore, quality loss incurred due to deviation of quality characteristics of the target with a specified tolerance. This article discusses the development of concurrent engineering optimization model of tolerance design and manufacturing process selection on product with multiple quality characteristics by minimizing total costs in the system, namely total manufacturing cost and quality loss cost as functions of tolerance, also rework and scrap costs. The considered multiple quality characteristics have interrelated tolerance …


Modification Of Flow Structure Over A Van Model By Suction Flow Control To Reduce Aerodynamics Drag, Harinaldi Harinaldi, Budiarso Budiarso, Warjito Warjito, Engkos Achmad Kosasih, Rustan Tarakka, Sabar Pangihutan Simanungkalit, I Gusti Made Fredy Lay Teryanto Apr 2012

Modification Of Flow Structure Over A Van Model By Suction Flow Control To Reduce Aerodynamics Drag, Harinaldi Harinaldi, Budiarso Budiarso, Warjito Warjito, Engkos Achmad Kosasih, Rustan Tarakka, Sabar Pangihutan Simanungkalit, I Gusti Made Fredy Lay Teryanto

Makara Journal of Technology

Automobile aerodynamic studies are typically undertaken to improve safety and increase fuel efficiency as well as to find new innovation in automobile technology to deal with the problem of energy crisis and global warming. Some car companies have the objective to develop control solutions that enable to reduce the aerodynamic drag of vehicle and significant modification progress is still possible by reducing the mass, rolling friction or aerodynamic drag. Some flow control method provides the possibility to modify the flow separation to reduce the development of the swirling structures around the vehicle. In this study, a family van is modeled …


Optimizing Fermentation Medium To Produce Cyclosporin A Using Response Surface Methodology, Rofiq Sunaryanto Apr 2012

Optimizing Fermentation Medium To Produce Cyclosporin A Using Response Surface Methodology, Rofiq Sunaryanto

Makara Journal of Technology

Response surface methodology (RSM) is a three factorial model which illustrates the relationship between one or more independent variables. RSM can be used to optimize the fermentation medium for the production of Cyclosporin A from the isolate Tolypocladium inflatum. The optimal point of the response surface area is predicted by using a seconddegree polynomial model and applying the statistic model obtained from the central composite design (CCD). The results of optimizing the fermentation medium for Cyclopsorin using the three independent variables of glucose, casein, and KH2PO4 show that all three of the independent variables affect the production of Cyclosporin A. …


Soil Greenhouse Gas Emissions In The Life Cycle Assessment Of Cellulosic Ethanol From Crop Residue, Xiao Xue Fang Apr 2012

Soil Greenhouse Gas Emissions In The Life Cycle Assessment Of Cellulosic Ethanol From Crop Residue, Xiao Xue Fang

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Concerns about climate change and the increasing cost of fossil fuels have led to interest in the development of renewable biofuel pathways for reducing greenhouse gas (GHG) emissions. The use of corn residue as a potential source of biomass feedstock for cellulosic ethanol production has been favored as cost effective. Previous research has shown that crop residue removal can cause a loss of soil organic carbon (SOC), which potentially is a source of GHG emissions in the form of CO2. Using a life cycle assessment (LCA) approach, this study investigated the impact of corn residue removal on total …


Detection And Analysis Of Sludge Bulking Events Using Data Mining And Machine Learning Approach, Yuanhao Zhao Apr 2012

Detection And Analysis Of Sludge Bulking Events Using Data Mining And Machine Learning Approach, Yuanhao Zhao

Master's Theses (2009 -)

Sludge bulking is the most notable cause of activated sludge plant failure (i.e. exceeding discharge permit quality limits) worldwide. Numerous mathematical methods have been applied to detect and provide warning for the prevention of sludge bulking. However, these models often fail to reliably forecast sludge bulking events because they focus on the point-by-point "curve-fitting" strategy, while the number of bulking event data points is relatively small in comparison with the large amount of data in the time series. Therefore, three machine learning approaches which focus on detecting the temporal pattern data before the sludge bulking events are considered in this …


Evaluation Of The Bank Stability And Toe Erosion Model (Bstem) For Predicting Lateral Retreat On Composite Streambanks, Taber L. Midgley, Garey A. Fox, Derek M. Heeren Apr 2012

Evaluation Of The Bank Stability And Toe Erosion Model (Bstem) For Predicting Lateral Retreat On Composite Streambanks, Taber L. Midgley, Garey A. Fox, Derek M. Heeren

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Streambank erosion is known to be a major source of sediment in streams and rivers. The Bank Stability and Toe Erosion Model (BSTEM) was developed in order to predict streambank retreat due to both fluvial erosion and geotechnical failure. However, few, if any, model evaluations using long-term streambank retreat data have been performed. The objectives of this research were to (1) monitor long-term composite streambank retreat during a hydraulically active period on a rapidly migrating stream, (2) evaluate BSTEM’s ability to predict the measured streambank retreat, and (3) assess the importance of accurate geotechnical, fluvial erosion, and near-bank pore-water pressure …


Impact Of Signal Timing Information On Safety And Efficiency Of Signalized Intersections, Anuj Sharma, Lelitha Vanajakshi, V. Girish, M. S. Harshitha Apr 2012

Impact Of Signal Timing Information On Safety And Efficiency Of Signalized Intersections, Anuj Sharma, Lelitha Vanajakshi, V. Girish, M. S. Harshitha

Department of Civil and Environmental Engineering: Faculty Publications

Signalized intersections are provided in traffic networks to improve the safety and efficiency of vehicular and pedestrian movement. There are various measures under education, enforcement and engineering headings that are being attempted to improve safety and efficiency of operations at a signalized intersection. Provision of signal countdown timer, a timer showing the remaining red and green time in a phase, is one such measure and is commonly adopted in India. However, studies on effects of countdown timer under Indian traffic conditions are very scarce. Traffic heterogeneity and lack of lane discipline makes transferability of models developed in other countries (with …


Examining The Effectiveness And Robustness Of Sequential Data Assimilation Methods For Quantification Of Uncertainty In Hydrologic Forecasting, Caleb Matthew Dechant, Hamid Moradkhani Apr 2012

Examining The Effectiveness And Robustness Of Sequential Data Assimilation Methods For Quantification Of Uncertainty In Hydrologic Forecasting, Caleb Matthew Dechant, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

In hydrologic modeling, state-parameter estimation using data assimilation techniques is increasing in popularity. Several studies, using both the ensemble Kalman filter (EnKF) and the particle filter (PF) to estimate both model states and parameters have been published in recent years. Though there is increasing interest and a growing literature in this area, relatively little research has been presented to examine the effectiveness and robustness of these methods to estimate uncertainty. This study suggests that state-parameter estimation studies need to provide a more rigorous testing of these techniques than has previously been presented. With this in mind, this paper presents a …


Age, Gender, And Muscle Strength: A Study Based On Indonesian Samples, Henny Henny, Hardianto Iridiastadi, Iftikar Zahedi Sutalaksana Apr 2012

Age, Gender, And Muscle Strength: A Study Based On Indonesian Samples, Henny Henny, Hardianto Iridiastadi, Iftikar Zahedi Sutalaksana

Makara Journal of Technology

Age and gender have been commonly used as a main criterion in accepting a job aplicant, but it is usually not clear how these affect job performance. While a number of recent studies have been done that describe the relationships between age, gender, and participants capacity (e.g., muscle strength), the results have been inconclusive. In Indonesia, in particular, such issues have been rarely investigated, and it is still important to study the issue since the relationships between these factors are population-specific. This study aimed at describing the relationships between age and muscle strength among workers for both genders. Ninety-six male …


Circularly Polarized Microstrip Array Antenna For Ground Segment In Quasi-Zenith Satellite System, Fitri Yuli Zulkifli, Eko Tjipto Rahardjo Apr 2012

Circularly Polarized Microstrip Array Antenna For Ground Segment In Quasi-Zenith Satellite System, Fitri Yuli Zulkifli, Eko Tjipto Rahardjo

Makara Journal of Technology

In satellite communication system, antenna plays an important role. Therefore, the antenna must meet some requirements, such as high gain, circular polarization, and good directivity. In this paper, a four element linear array triangular patch microstrip antenna with cross slot is designed to be used for Quasi-Zenith satellite system. A simulation study as well as experimental study was carried out. The simulation showed that the 3 dB axial ratio bandwidth of 87 MHz (2.569-2.656 GHz) is achieved while the measured results showed 96 MHz (2.556-2.652 GHz). The linear array of 4 element antenna has a gain of 13.73 dB and …


Tolerance Limit For Trucks With Excess Load In Transport Regulation In Indonesia, Sigit Pranowo Hadiwardoyo, Raden Jachrizal Sumabrata, Mohammed Ali Berawi Apr 2012

Tolerance Limit For Trucks With Excess Load In Transport Regulation In Indonesia, Sigit Pranowo Hadiwardoyo, Raden Jachrizal Sumabrata, Mohammed Ali Berawi

Makara Journal of Technology

Reliability of a road is mandatory since damaged will impede the traffic. Destruction is caused by various factors; one of the most important factors is excess load. Overload may give the load of each axle of a vehicle exceeds the determined standard. This condition occurs in trucks exceeding the load limit. In designing the structure of a road based on the method of Directorate General of Highways Ministry of Public Works of the Republic of Indonesia, axle load calculated in equivalent-number, or known as equivalent axle load (EAL), of 8.16 tons of standard axle. Total equivalent-number over the service life …


Earthquake Damage Intensity Relationship For Residential Houses In West Sumatra, Febrin Anas Ismail, Abdul Hakam, Fauzan Fauzan Apr 2012

Earthquake Damage Intensity Relationship For Residential Houses In West Sumatra, Febrin Anas Ismail, Abdul Hakam, Fauzan Fauzan

Makara Journal of Technology

The Sumatra 30 September 2009 earthquake has damaged hundred thousand buildings in West Sumatra Province. The earthquake is located in 100 km offshore of Padang City, the Capital City of the province. Survey has been conducted to assess the damage of the building in few days after the earthquake. In this survey, the damage of buildings are categorised into 3 level that are heavily, moderate and slightly damages. This paper explores the level damage of building and then the intensity of the shaking in the affected area. Then based on the coordinate of every building location, the buildings are scattered …


Evaluation Of Universitas Indonesia’S Recharge Pond Performance And Potential Utilization For Raw Water Source, Nyoman Suwartha, Resky Agaslian Pramadin Apr 2012

Evaluation Of Universitas Indonesia’S Recharge Pond Performance And Potential Utilization For Raw Water Source, Nyoman Suwartha, Resky Agaslian Pramadin

Makara Journal of Technology

Evaluasi Kinerja Waduk Resapan UI dan Potensi Pemanfaatannya sebagai Sumber Air Baku. Waduk resapan Universitas Indonesia (UI) telah dibangun sejak 5 tahun yang lalu. Namun kegiatan monitoring dan evaluasinya sangat minim dilakukan. Tujuan dari studi ini adalah untuk mengetahui laju resapan, dan untuk mengevaluasi kondisi kuantitas dan kualitas air waduk resapan selama musim kemarau dan penghujan. Pengukuran kedalaman muka air, intensitas curah hujan dan penguapan dilakukan untuk menentukan ketersediaan air, laju resapan, dan imbangan air waduk. Sejumlah air permukaan diambil dari waduk resapan dan sungai di tiga titik sampling untuk mengetahui kondisi kualitas air eksisting. Hasil studi menunjukkan tidak ada …


Effect Of Methanol Induction And Incubation Time On Expression Of Human Erythropoietin In Methylotropic Yeast Pichia Pastoris, Adi Santoso, Neng Herawati, Yana Rubiana Apr 2012

Effect Of Methanol Induction And Incubation Time On Expression Of Human Erythropoietin In Methylotropic Yeast Pichia Pastoris, Adi Santoso, Neng Herawati, Yana Rubiana

Makara Journal of Technology

Erythropoietin (EPO) is a glycoprotein hormone consists of 165 amino acids and has molecular mass of 30,400 Daltons. The large quantities of these hormone required to satisfy clinical demand are currently met by recombinant expression in mammalian cell, namely chinese hamster ovary (CHO). Pichia pastoris has become popular yeast based protein production systems to substitute mammalian expression systems. P. pastoris is capable to use methanol as sole carbon and energy source. In this study, recombinant human EPO (rhEPO) protein obtained by expressing the hEPO gene in methylotropic yeast P. pastoris, strain X33. The present work was carried out to study …


Fuel Saving Strategy In Spark Ignition Engine Using Fuzzy Logic Engine Torque Control, Aris Triwiyatno, Sumardi Sumardi Apr 2012

Fuel Saving Strategy In Spark Ignition Engine Using Fuzzy Logic Engine Torque Control, Aris Triwiyatno, Sumardi Sumardi

Makara Journal of Technology

In the case of injection gasoline engine, or better known as spark ignition engines, an effort to improve engine performance as well as to reduce fuel consumption is a fairly complex problem. Generally, engine performance improvement efforts will lead to increase in fuel consumption. However, this problem can be solved by implementing engine torque control based on intelligent regulation such as the fuzzy logic inference system. In this study, fuzzy logic engine torque regulation is used to control the throttle position entered by the driver to achieve optimal engine torque. An engine torque vs. throttle position and engine speed mapping …


An Agri-Food Supply Chain Model To Enhance The Business Skills Of Small-Scale Farmers Using Corporate Social Responsibility, Wahyudi Sutopo, Muh. Hisjam, Yuniaristanto Yuniaristanto Apr 2012

An Agri-Food Supply Chain Model To Enhance The Business Skills Of Small-Scale Farmers Using Corporate Social Responsibility, Wahyudi Sutopo, Muh. Hisjam, Yuniaristanto Yuniaristanto

Makara Journal of Technology

In general, small-scale vegetable farmers experience problems in improving the safety and quality of vegetables for supplying high-class consumers in modern retailers. Farmer Group and/or Cooperative (FGC) should be able to assist its members to meet the relevant provisions of modern retail on product specifications, delivery terms, and internal business requirements. This study proposed an agri-food supply chain (ASC) model that involves the corporate social responsibility (CSR) activities to enhance the business skills of the FGC as supplier of modern retailer. Multi-objective optimization programming is developed to determine the amount and timing of supply, level of farmers training skills, quality …


Pineapple Liquid Waste As Nata De Pina Raw Material, Agus Sutanto Apr 2012

Pineapple Liquid Waste As Nata De Pina Raw Material, Agus Sutanto

Makara Journal of Technology

This research aims to study the quantity, quality, ecological and economic feasibility of nata de pina production (NP) from pineapple liquid waste (PLW). The design of the study employs complete random design (CRD) with three treatments: PLW without nutrients addition (A), PLW nutrients addition (B), and PLW stored for six months with nutrients addition (C). The nata de pina’s production factors measured were weight, thickness, fiber content, color, brightness, and residual waste. The highest weight was reached in treatment B (899 grams), followed by treatment A (616.4 grams), and C (477.8 grams). The thickness of NP of the height and …


Modeling Of A New Structure Of Precision Air Conditioning System Using Secondary Condenser For Rh Regulation, Aries Subiantoro, Nasruddin Nasruddin, Feri Yusivar, Muhammad Idrus Al-Hamid, Bagio Budiardjo Apr 2012

Modeling Of A New Structure Of Precision Air Conditioning System Using Secondary Condenser For Rh Regulation, Aries Subiantoro, Nasruddin Nasruddin, Feri Yusivar, Muhammad Idrus Al-Hamid, Bagio Budiardjo

Makara Journal of Technology

A dynamic mathematical model for a new structure of precision air conditioning (PAC) has been developed. The proposed PAC uses an additional secondary condenser for relative humidity regulation compared to a basic refrigeration system. The work mechanism for this system and a vapour-compression cycle process of the system are illustrated using psychrometric chart and pressure-enthalpy diagram. A non-linear system model is derived based on the conservation of mass and energy balance principles and then linearized at steady state operating point for developing a 8th-order state space model suited for multivariable controller design. The quality of linearized model is analyzed in …


Measuring Bridge Construction Efficiency Using The Wireless Real-Time Video Monitoring System, Yong Bai, Jun Huan, Seonghoon Kim Apr 2012

Measuring Bridge Construction Efficiency Using The Wireless Real-Time Video Monitoring System, Yong Bai, Jun Huan, Seonghoon Kim

Civil and Environmental Engineering Faculty Research and Publications

To enhance the efficiency of bridge construction, the wireless real-time video monitoring system (WRITE) was developed. Utilizing the advanced technologies of computer vision and artificial neural networks, the developed system first wirelessly acquired a sequence of images of work-face operations. Then human pose analyzing algorithms processed these images in real time to generate human poses associated with construction workers who performed the operations. Next, a portion of the human poses were manually classified into three categories as effective work, contributory work, and ineffective work and were used to train the built-in artificial neural networks (ANN). Finally, the trained neural networks …