Energy Conservation Method Research Articles

응용프로그램의 작업량을 고려한 임베디드 프로세서의 동적 전압 조절

휴대용 기기의 다양한 기능으로 인해 에너지 절약은 더욱 중요한 문제가 되고 있다. Dynamic Voltage Scaling(DVS)는 임베디드 기기에서 대표적으로 사용되는 에너지 절약 방법이다. 본 논문에서는 응용프로그램의 작업량 변화에 따라 프로세서의 동작 전압과 속도를 조절할 수 있는 DVS 알고리즘을 제안한다. 제안된 DVS 알고리즘은 커널의 DVS 모듈과 응용프로그램의 작업량 변화를 관찰하는 함수로 구성되어 있으며 작업량이 급격히 증가하거나 감소하는 경우 이에 알맞은 프로세서의 동작 수준을 결정함으로서 작업의 데드라인을 넘기지 않으면서도 전력 소비를 줄일 수 있도록 하였다. 제안된 DVS 알고리즘은 Linux 2.6 커널과 PXA270프로세서를 이용한 임베디드 시스템에서 구현되었다.

An atomistic-to-continuum coupling method for heat transfer in solids

In this work, we present a seamless, energy-conserving method to couple atomistic and continuum representations of a temperature field in a material. This technique allows a molecular dynamics simulation to be used in localized regions of the computational domain, surrounded and overlaid by a continuum finite element representation. Thermal energy can pass between the two regions in either direction, making larger simulations of nano-scale thermal processes possible. We discuss theoretical developments and numerical implementation details. In addition, we present and analyze a set of representative simulations.

An Approach to Energy Conscious Renovation of Residential Buildings by a Trombe Wall System

Turkey has a great potential for solar energy, the primary source of renewable energy. Heating uses 36% of the total energy consumed in buildings in Turkey. Heating energy consumption and energy conservation methods become necessary due to the lack of regulations for encouraging the utilization of solar energy. In this study, the south facade of a flat in existing buildings in Istanbul and Erzurum (representative cities in Turkey for mild-humid and cold regions) are renovated by the application of the Trombe wall principle, a well-known indirect passive solar gain system. An approach is proposed for this application and the comparison of the existing facades with the renovated facades was done according to thermal performance and hourly variations of interior wall temperatures. Since most energy efficient renovation standards in the world recommend increasing the thickness of insulation, the results are compared with highly insulated walls. In this study, it has been shown that insulation only helps to decrease heat loss through the envelope if you have an internal heating system, but a Trombe wall transfers solar heat gain, thus saving on the use of mechanical heating systems for some climatic regions of the world.

A multi-phase AC arc discharge and its application in in-flight thermal treatment of raw glass powders

The in-flight melting technology with multi-phase alternating current (AC) arc was developed for the purpose of saving energy and shortening production cycle for glass industry. The 6-phase arc and 12-phase arc were used to investigate the in-flight melting behavior of soda-lime and alkali-free glass powders. Results showed that the vitrification degree of raw materials and the shrinkage of particle diameter increased with the increase of input power. The higher melting temperature and viscosity were responsible for the lower vitrification degree of alkali-free glass powders. Compared with 6-phase arc, 12-phase arc improved the vitrification degree of raw material for the longer residence time and higher plasma temperature under the same transformer current. The high vitrification degree achieved in short time indicated that the new in-flight melting technology with multi-phase ac arc would be a promising method for energy conservation in glass industry.

An approach for energy conscious renovation of residential buildings in Istanbul by Trombe wall system

Turkey has a great potential of solar energy, which is the primary source of renewable energy; however, sufficient benefit cannot be obtained from this clean energy source. In Turkey, 36% of the total energy consumed in buildings is used for heating. Due to the lack of regulations in encouraging the solar energy utilization in buildings, the heating energy consumption plays an important role in the energy economy of our country. Therefore, energy conservation methods become necessary. Energy conservation is important for the existing buildings as for the new buildings. In this study, the south facade of a flat in an existing building in Istanbul in Turkey is recommended to be renovated by the application of Trombe wall principle, which is a well-known indirect passive solar gain system. An approach is proposed for this application and the comparison of the existinsg facade with the renovated facades has been made according to thermal performances and hourly variations of wall interior temperatures. The results of this theoretical application study are given in this paper.

Why Music Majors Pursue Music Despite the Risk of Playing-related Injuries

Music is an occupation that has existed across cultures and societies for millennia. What music means and how it is used differ depending on the context of an individual's life. University music majors often pursue music as a future career goal, despite the fact that playing-related injuries are a significant risk for this population and could end their careers. The purpose of this study was to investigate why university music majors pursue music despite the risk of playing-related injuries. This qualitative study used a naturalistic approach and focus groups to collect data. Nine students participated in two focus group sessions. The data were transcribed verbatim and analyzed for themes. The results of the study indicate that both personal and environmental factors influence the participants' decision to continue to participate in music. Some students also were willing to play through pain, which is contrary to Maslow's theory of human needs, and many students experienced difficulties accessing desirable health care. Although an injury could terminate a student's ability to participate in music, the occupation of music itself transcended this danger. For several musicians, quitting was not a desirable option. These findings have clinical implications for health care workers with respect to modifying treatment to address musicians' specialized needs. Occupational therapists use a holistic and client-centered approach to care and offer interventions such as compensatory techniques, assistive devices, and methods of energy conservation that may facilitate continuing with this valued occupation.

Prediction of height effect, plastic deformation and fracture energy for high-strength concrete by linear shear softening constitutive relation based on energy conservation method

Based on the energy conservation method, the slopes of post-peak stress–deformation curves undergoing class I behaviour and class II behaviour are presented for a high-strength concrete specimen subjected to shear failure in the form of shear band exhibiting linear strain softening beyond peak shear stress. The predicted height effect coincides well with the previous experiments. The transition occurs from class I behaviour to class II behaviour as specimen height increases. The slope of the relative stress–plastic deformation curve is derived. The horsetail-like profile of the measured curves for different heights cannot be explained if shear band inclination is only related to friction or/and dilation angles. The deduction that shear band inclination depends on specimen height is verified by previous experiments and numerical prediction using fast Lagrangian analysis of continua. If the dependence of strength and shear band inclination on geometrical size is neglected, then post-peak shear fracture energy is a material parameter. The linear regression on scattered experimental data shows that post-peak fracture energy is independent of specimen height, as is consistent with the present analysis regardless of the size effects of strength and shear band inclination. The size-dependent strength and shear band inclination as well as the sensitivity of shear band inclination and pattern to boundary condition and position of material imperfections are responsible for the scattered post-peak shear fracture energy.

ENERGY AUDIT – METHOD FOR ENERGY CONSERVATION IN HOTELS

: In the very near future, energy efficient hotels will cease to be the exception but will be the rule. Energy conservation and the intelligent utilization of renewable energy sources are prerequisite for sustainable development of tourism. Due to global warming and increased standards in hotel industry, there is an increasing demand for energy for cooling in general, although this is especially reflected in hotel industry peaking in summer period. Furthermore, energy demand for hot water and food and beverages preparation in a hotel increases proportionally with the number of tourists. All these energy issues are overburdening the ever competing hotel industry. Hotels, in order to optimize their energy costs and implementation of renewable energy sources utilization, have to perform energy audit - an analysis of thermal performance and energy systems of building with the purpose to determent its energy efficiency or non-efficiency. This paper combines energy audit methodology with properties of energy consumption in hotel industry with an aim to provide guidelines for modern hotel energy management.

Accuracy analysis of geopotential coefficients recovered from in-situ disturbing potential by energy conservation method

The characteristics of the normal equation created in recovering the Earth gravity model (EGM) by least-squares (LS) adjustment from the in-situ disturbing potential is discussed in detail. It can be concluded that the normal equation only depends on the orbit, and the choice of a priori gravity model has no effect on the LS solution. Therefore, the accuracy of the recovered gravity model can be accurately simulated. Starting from this point, four sets of disturbing potential along the orbit with different level of noise were simulated and were used to recover the EGM. The results show that on the current accuracy level of the accelerometer calibration, the accuracy of the EGM is not sufficient to reflect the time variability of the Earth’s gravity field, as the dynamic method revealed.

Application of Ultraviolet Treatment in the Synthesis of Pure-silica Zeolite Thin Films with Low Dielectric Constant

Transparent pure-silica zeolite (PSZ) films were synthesized on silicon wafers through hydrothermal reaction, in which tetraethyl orthosilicate (TEOS) was used as silica source, tetrapropyl ammonium hydroxide (TPAOH) as template and alkaline source. An ultraviolet treatment was subsequently applied to remove the organic templates within the pores/channels of zeolite films. The thin films were characterized by using FTIR, XRD, and SEM techniques before and after the ultraviolet treatment. FTIR results showed that the organic templates were effectively removed via ultraviolet treatment, which was the same as the results from the calcinations treatment. In comparison with the calcined films, XRD and SEM results indicated that the crystallinity and the surface as well as the thickness of the films had no significant changes after ultraviolet treatment. Dielectric constant (e) values of the thin films were measured by means of impedance analyzer. Elastic modulus and hardness of the thin films were measured by the nano-indentation technique. All results showed that the films after ultraviolet treatment had a lower e value and higher mechanical strength. Therefore, it could be concluded that ultraviolet treatment was a faster, more energy-conservative method to remove template from zeolite films, in comparison with conventional calcination.

Building Design Strategies and Their Contribution to Energy Performance for LEED Certification

Leadership in Energy and Environmental Design (LEED) is a national set of standards put forth by the U. S. Green Building Council in 1994 that was intended to inspire building designers to plan greener, more sustainable buildings. LEED offers up to ten points for improved energy optimization performance. It should be noted that achieving these ten points is time consuming, complex, and expensive. This research is a case study that details the process of using a computer simulation study as a building energy optimizing tool in order to achieve these optional points. Determination is made as to how many LEED points can be obtained when basic strategies such as window performance and day-lighting are integrated into one energy optimized building design. The results show that well-established energy conservation methods achieve as few as two or three LEED energy points, thereby possibly offering a disincentive for designers to attempt this difficult challenge. These fundamental efforts to achieve energy optimized building design are the first steps toward high performance building design and offer a fundamental solution to the substantial, negative environmental impacts caused by buildings today.

Educating patients suffering from re-acutisation of chronic bronchitis. A pilot support project within Intermediate Care

Background: Chronic Obstructive Pulmonary Disease (COPD) represents one of the main causes ofhospitalization, disability and mortality worldwide; it is predicted that by the year 2020 it will become thethird leading cause of death and the fifth leading cause of disability in industrialized countries.An educational programme has been proposed to allow the COPD patient to prevent or to deal with a re-acutisation.Methods: The project involved 50 patients with a diagnosis of moderate or severe COPD. The educationprogram included information relating to disease process, proper use of medication, energy conservationmethods, and the filling in of the Saint George’s Respiratory Questionnaire (SGRQ), the Zung Self-RatingDepression Scale (ZSDS) and the State Trait Anxiety Inventory (STAI). Sociodemographic factors,assessment of living arrangements, social and family conditions were also collected. One year later the samequestionnaires and learning assessment tests were re-administered.Results: The mean age of the participants was 69.7±10.4 years with a mean low income and a limited degreeof education. Following the educational program, an improvement of quality of life emerged consequent tothe awareness of all of the forms of support provided for the pathology and socio-economic conditions. Theability to manage their therapy and their activities of daily living have improved. The mean total score onSGRQ was 78.07±7.2 pre-program and 73.12±7.2 post-program; 52% of the patients are now within normalparameters compared to the initial 30% suffering from depression syndrome, furthermore the mean anxietyvalue decreased from 59.54 ± 8.6 to 54.54±7.8. The number of hospital admissions and the number ofsmokers were also halved.Conclusion: The improvements obtained after conducting all of the educational sessions are significant. Thehigh value of the mean total score on SGRQ suggests overall poor health among patients affected bymoderate/ severe COPD and according to other studies this population is inclined to anxiety and depression.The role of the social worker was very important because the explanation of the appropriate laws has leadto the recognition of their disability status and therefore access to established benefits. The decrease inhospitalization has brought about an economic benefit for the educational program but further studiesshould be carried out on more patients over longer periods of time

Calibration for CHAMP accelerometer data based on crossover points of the satellite

The German CHAlleging Minisatellite Payload (CHAMP) was launched in July 2000. It is the first satellite that provides us with position and accelerometer measurements, with which the gravity field model can be determined. One of the most popular methods for geopotential recovery using the position and accelerometer measurements of CHAMP is the energy conservation method. The main aim of this paper is to determine the scale and bias parameters of CHAMP accelerometer data using the energy conservation method. The basic principle and mathematical model using the crossover points of CHAMP orbit to calibrate the accelerometer data are given based on the energy balance method. The rigorous integral formula as well as its discete form of the observational equation is presented. This method can be used to estimate only one of the scale and bias parameters or both of them. In order to control the influence of outliers, the robust estimator for the calibration parameters is given. The results of the numerical computations and comparisons using the CHAMP accelerometer data show the validity of the method.

Don't Even Say Energy Conservation–It's “Energy Productivity”

ABSTRACT The strategic energy related opportunities in manufacturing which sharply reduce production costs are often never identified. Even when identified, these low-risk investments, which provide very compelling financial returns, are often rejected when non-energy related investments, which have a higher risk and less compelling financial results, are implemented. In part one of this article, we explained why the energy opportunities which will radically improve business results must be built upon manufacturing initiatives, not conservation. Energy productivity is the focus. It's not about energy savings. It is about optimizing energy as a factor of production, leading to an energy epiphany. The best opportunities will improve the production rate, which may increase or decrease energy use. With the conventional, less effective, energy conservation methods, the “energy auditor” (a word we shouldn't use) looks for which of the usual energy saving technologies “fit” at a plant. This is like a solution se...

Adaptive traffic-based control method for energy conservation in wireless devices

Mobile units have many constraints for reliable communication in today’s mobile environments. Unlike wired networks in mobile networks, mobility induces frequent route changes. Energy conservation is an important issue that has to be taken into account for mobile devices. Every infrastructureless network must be adaptively self-configured particularly in terms of energy, connectivity, resource allocation and memory. Efficient utilization of battery power is important for wireless users because due to their movements their energy is fluctuating at different levels during operation mode. Traffic plays a major role for energy consumption because of the unpredictable incoming flow nature. Generally, the minimum transmission power required to keep the network connected achieves the optimal throughput performance in a dynamically changing topology network. In this paper an adaptive traffic-based control method for energy conservation is described and examined, which bounds an asynchronous operation where each node evaluates dissimilar sleep-wake schedules/states based on each node’s incoming sleep-history traffic. Simulation study is carried out for throughput, traffic characterization against performance and energy conservation evaluation of the proposed model taking into account a number of metrics and estimation of the effects of incrementing the sleep time duration to conserve energy. The proposed method could be applied to infrastructureless networks with any underlying routing protocol to provide independency, portability, as well as “fair” collaboration among energy conservation mechanism and routing protocol.

A study on the energy consumption unit of subway stations in Korea

As the Korean economy and society continues to develop, the number of subways are expected to increase. This increase will demand greater heating and cooling energy as well as convey a sharp rise in the overall energy consumption. This study aims to develop energy conservation and analysis for subways. This study shows the information, that is, tables, graphs, and charts concerning the trend in energy efficiency in subways between 1999 and 2001. We suggest a practical application for energy conservation methods and efficient energy use based on the investigations and analyses.

A novel energy conservation method—optimal chiller loading

This paper presents an approach using Lagrangian method to solve the optimal chiller loading (OCL) problem and to improve the deficiencies of conventional methods. The coefficient of performance (COP) of a chiller is chosen as the objective function for the reason of being a concave function. The potential performance of the proposed method is demonstrated by mean of two example systems. Compared with the conventional methods, the proposed method has much less power consumption and good accuracy, and is very suitable for application in air-condition system operation.

Analysis of one month of CHAMP state vector and accelerometer data for the recovery of the gravity potential

Abstract. The energy conservation method is based on knowledge of the state vector and measurements of nonconservative forces. This is or will be provided by CHAMP, GRACE and GOCE. Here the analysis of one month of CHAMP state vector and accelerometer data is described. The energy conservation method is used to estimate the gravity potential at satellite altitude. When doing so we consider the tidal potential from the sun and the moon, the explicit time variation of the gravity potential in inertial space and loss of energy due to external forces. Fast Spherical Collocation have been used to estimate a gravity field model to degree and order 90, UCPH2002 04. This gravity field model is compared to EGM96 and EIGEN-2. The largest differences with respect to EGM96 are found at those places where the gravity data used to determine EGM96 had the largest uncertainty. EIGEN-2 and UCPH2002 04 are similar, though there are some differences in Antarctica and Central Asia.

Laboratory chemical hoods: a historical perspective.

A historical review of laboratory fume hoods leads to a consideration of the current status of structural design, operating characteristics (with special reference to face velocity), safety (relative to standardized test results), energy conservation, and certification methods. Noteworthy are (1) the increasing complexity of instrumentation designed to assure full safety function plus airflow modulation to minimize energy consumption; (2) the extreme plasticity of accepted and recommended face velocity values; (3) the insensitivity of standardized hood test protocols to variations in face velocity; and (4) a serious lack of correlation between operator risk, face velocity, and standard hood test results. Safety considerations lead to the selection of laboratory fume hoods having the highest demonstrated containment capability. This is in spite of the fact that most hood operations have a low hazard rating. Energy savings could be realized if the face velocity of each hood could be modulated to match the risk associated with the work being conducted.

Analysis and Modeling of Electro-Mechanical Coupling in an Electroactive Polymer-Based Actuator

ABSTRACTA non-linear constitutive model was formulated for ionic electroactive polymers (EAP) to describe the energetic coupling between electrical and mechanical domains. The polymer was modeled as a multi-port energy storage element with inputs from the electrical and mechanical domain. Using energy conservation methods, general relationships between stress, strain, voltage, and charge were determined. A solution to the uniaxial loading boundary condition was developed fully and compared to a linear model published by Madden and an electrochemical model published by Mazzoldi et al. Experimental results from a conducting polymer actuator composed of polypyrrole were used to validate the electro-mechanical coupling model. It was found that the correlation between the model and experimental data was very good for strains up to 3% and applied voltages up to 1 Volt; these are within the typical operating range of polypyrrole. The model is sufficiently simply to allow real-time control while also exceeding the linear coupling models in its ability to predict polymer behavior in normal operating ranges.