bluuebunny/crossref_metadata_2025 huggingface dataset:
TURBULENT-FORCED CONVECTIVE HEAT TRANSFER AND PRESSURE DROP ANALYSIS OF FE3O4 MAGNETIC NANOFLUID IN A CIRCULAR MICROCHANNEL
Authors: Che Sidik Nor Azwadi , Yassin M.M. , Musa M.N.
Published: September 2015

A numerical simulation was accomplished in this study that investigated the turbulent force convective heat transfer and pressure drop in straight circular copper pipe with a hydraulic diameter of 0.0005m and 0.1m in length, as given by Lee and Mudawar [11]. The enhancement of heat transfer for water and nanofluids (Fe3O4) under 100 [W/m2] constant heat flux was applied around the wall of the pipe. In this study, standard k-ɛ turbulence model was employed and was performed at a steady state flow, incompressible turbulent flow, and three-dimensional structure. Various volume concentrations of nanoparticles were conducted in the range of 1% to 15% at constant nanoparticle diameter size, which was 32 nm. The heat transfer enhancement was obtained in the range of Reynolds number from 3000 to 10,000. The results displayed an increase in Reynolds number and volume concentrations, as well as an increase in the Nusselt number. The optimum Nusselt number gained was about 5% to 6% of volume concentration at each Reynolds number tested. Besides, with the increase of Reynolds number, the variation pressure saw a dropped for inlet, whereas an increase in the outlet section. Moreover, the  increase in volume concentration also caused a small increment in the pressure drop compared to pure water.
FRACTURE MODELING IN OIL AND GAS RESERVOIRS USING IMAGE LOGS DATA AND PETREL SOFTWARE
Authors: Alizadeh Mostafa , Movahed Zohreh , Junin Radzuan , Mohsin Rahmat , Alizadeh Mehdi , Alizadeh Mohsen
Published: September 2015

The purpose of modelling the fractures is to create simulation properties with the power to predict the reservoir behaviour. Petrel software is one of the best softwares in the market that can do this task very well, but there is no available educational paper for every researcher. Therefore, in this work, a fracture modelling job was done in one of the most important Iranian fields using Petrel software and image log data. The purpose of this work was  to determine the new information of the fractures in Gachsaran field and also to prepare a valuable educational paper for other researchers who are interested to learn about the fracture modelling. This work revealed that in this field, the longitudinal fractures had been parallel to minimum stress (Zagros trend), fracture intensity was the nearest to the major fault and northern flank, fracture porosity was 0-7%, fracture permeability was 0-6000 MD, and more valuable information is provided in this paper.
NATURAL CONVECTION OF ALUMINIUM OXIDE-WATER NANOFLUID
Authors: Afifah A.N. , Syahrullail S. , Nor Azwadi C.S.
Published: September 2015

As suspending nanoparticles in fluid-based give tremendous promise in heat transfer application, an understanding on the mechanism of heat transfer is indispensable. The present study dealt with natural convection of nanofluid inside a square cavity heated at the bottom, while the upper part was exposed to the atmosphere. Experimental studies have been performed for various physical conditions, such as volume fractions of nanoparticles varying from 0% to 2.0%, different dispersion techniques of nanoparticles in fluid-based, and heating time from 0 to 35 minutes. In general, dynamic viscosity of nanofluid clearly increased with volume fraction, but decreased with the increasing temperature. It was found that improper dispersion technique resulted in viscous solution. On top of that, transport mechanism of thermophoresis and Brownian diffusion were considered in analysing heat transfer across the cavity.
TOWARDS A FRAMEWORK FOR PROMOTING SUSTAINABLE CONSTRUCTION IN MALAYSIA
Authors: Idris Nur Hidayah , Ismail Zulhabri , Hashim Harwati
Published: September 2015

This research aims to propose a framework for promoting sustainable construction in Malaysia. Issues that related with environmental destruction in Malaysia have been heard regularly due to negative impacts from human development especially construction activities. This growing concern makes the government and private sectors in Malaysia to be more proactive in minimising this problem without restraining the need for development. In this research, mixed methods of quantitative and qualitative research were adopted prior to developing a framework for promoting sustainable construction in Malaysia. A list of 11 impediments was preliminarily identified through extensive literature review. This was followed by questionnaire survey to collect the developers opinion on the relative importance of these factors. Using relative importance index (RII) analysis, the 11 impediments were listed according to their most importance factors. Further, the qualitative research was conducted in order to further confirm the most important impediments and the strategies to promote sustainable construction in Malaysia. Findings indicated four impediments: cost, government roles, lack of awareness, and insufficient green product supplier. The framework suggests that the government should play an important role to increase demand on sustainable project by providing supports in terms of cost and promulgate green product supplier to construction practitioner for more sustainable projects.
ASSESSMENT OF RIVER PLAN CHANGE USING RS AND GIS TECHNIQUE
Authors: Kamarudin M. K. A. , Toriman M. E. , Juahir H. , Azid A. , Gasim M. B. , Saudi A. S. M. , Umar R. , Sulaiman N. H. , Ata F. M. , Mustafa A. D. M , Amran M. A. , Yusoff W. A. , Azaman F.
Published: September 2015

Rivers is one of the complex natural systems. Classification of the river plan change is very important to know the river problems in early stage, where the classification database can help to understand the behavior of the river in each part. This article discusses about the classification of river plan change at the mainstream of Pahang River, Malaysia. Based on Geographical Information System (GIS) and Remote Sensing (RS) database, analysis of Types Of Lateral Activity (TYLAT) method and Modes of Meander Movement (MOME) method have been used to identify the evolution of the river plan change. The study results indicated, methods of TYLAT are more suitable to use for examining the evolution of river plan change for large and width rivers. While, method of analysis MOME index is more suitable for smaller types of rivers as the upper and middle reaches of the river. From this result, this study can be produced the basic information or database to understanding the characteristics or behavior parts in parts of the main Pahang River. This result also is very important to local authorities to know the early river problems in this area.
AN APPLICATION OF THE LEAN PRODUCTION TOOL STANDARD WORK
Authors: Bragança Sara , Costa Eric
Published: September 2015

Standard Work is a very useful tool of the Lean Production paradigm to specify standards and to establish the best methods and sequences for each process and for each worker, helping to reduce wastes. Despite its usefulness, this tool is often underused, neglected and misunderstood. Apart from that, there is a lack of literature about Standard Work. It is possible to find many papers on Lean Production in general and on some Lean tools, but there are few that focus on or describe in detail this particular tool. The main purpose of this paper is to prove the validity and show the importance and the applicability of Standard Work. The main aspects and ideas to understand this tool are described, as well as the benefits of applying it in a real world manufacturing environment. In this paper, an application example is given on a production unit of an elevators company, following the Action-Research methodology. The main findings are that Standard Work is effectively a good tool to normalize work procedures, allowing increased flexibility and production, and decreased wastes and assembly errors.
SYNTHESIS AND CHARACTERIZATION OF SELF-HEALING MORTAR WITH MODIFIED STRENGTH
Authors: Huseien Gassan Fahim , Mirza Jahangir , Ariffin Nur Farhayu , Hussin Mohd Warid
Published: September 2015

Cementitious materials being the most prospective building blocks achieving their absolute strength to avoid the deterioration in the early stage of service life is ever-demanding. Minimizing the labor and capital-intensive maintenance and repair cost is a critical challenge. Thus, self-healing mortars with modified strength are proposed. Lately, self-healing of micro-cracks by introducing bacteria during the formation of mortar or concrete became attractive. Self-healing with polymeric admixtures is considered to be relatively more durable and faster process. Certainly, the self-healing of synthetic polymeric materials is inspired by biological systems, where the damage triggers an autonomic healing response. This emerging and fascinating research initiative may significantly improve the durability and the safety limit of the polymeric components potential for assorted applications. In this work, using epoxy resin (diglycidyl ether of bisphenol A) without any hardener as admixture polymeric-cementitious materials is prepared. These epoxy-modified mortars are synthesized with various polymer-cement ratios subjected to initial wet/dry curing (WDC) together with long term dry curing (DC). Their self-healing function and hardening effects are evaluated via preloading and drying of the specimens, chemical analysis, and ultrasonic pulse velocity testing. It is demonstrated that 10% of polymer is the best proportion for polymer-cement ratio. Furthermore, the wet/dry curing is established to be superior process for healing hairline cracks present in the mortar. The excellent features of the results suggest that our novel method may constitute a basis for improving the compressive strength and self-healing features of mortars.
STAGNATION LAMINAR PREMIXED CH4/AIR FLAME SUBJECTED TO THE EQUIVALENCE RATIO OSCILLATIONS
Authors: Abdul Rahman Mohd Rosdzimin , Tomita Hishashi , Yokomori Takeshi , Ueda Toshihisa
Published: September 2015

The effect of the equivalence ratio oscillation on a premixed laminar CH4/air flame motion was studied experimentally with equivalence ratio oscillation frequencies of 2 to 15 Hz at lean equivalence ratio using stagnation flow field burner. Novel oscillator does the oscillation conditions and turbulence reduction method is used to suppress the velocity perturbation. The flame position variations at 2, 5, 10 and 15 Hz oscillation frequencies were significantly small when the amplitude of the equivalence ratio oscillation was zero. On the other hand, increase in amplitudes of the equivalence ratio oscillation increased the flame position variation significantly. The flame moved in sinusoidal shape and it can be clearly seen that the flame movement’s amplitude was proportional to the amplitudes of the equivalence ratio variations. This result showed that the velocity perturbation is significantly suppressed by turbulence reduction method in the examination range.
PENGGUNAAN CAMPURAN PLASTIK DAN KACA KITAR SEMULA SEBAGAI AGREGAT GANTIAN DALAM CAMPURAN BERASFALT
Authors: Zakaria Nur Mustakiza , Nong Radzif Derma Nur Ashikin , Hassan Mohammad Kamal , Hamim Asmah , Md. Yusoff Nur Izzi
Published: September 2015

The major problem in landfill is the large amount of solid wastes dumped in landfill. Waste plastics and glass contribute greatly to the problem and this needs to be managed in order to extend the life of landfill sites. Hence, this study was conducted to investigate the feasibility of using these waste materials in asphalt mixtures for pavement applications. The mixtures were designed by means of the Superior Performing Asphalt Pavements (Superpave) method. Various types of recycled waste plastics and glasses; namely bottle glass, LCD glass and sheet glass were selected in this study. Approximately 5% of recycled materials (by the total weight of asphalt mixtures) were used as an aggregate replacement. In this study, asphalt mixtures were aged in the laboratory to simulate the in-situ conditions of short-term and long-term ageing. After completion, samples were tested for resilient modulus, dynamic creep and static creep tests. It was found that replacements of 1% recycled plastics and 4% recycled glass show almost similar and satisfactory result compared to control sample for all tests. Consequently, recycled plastics and recycled glass, at their optimum blending, can be considered feasible to be used as an aggregate replacement in asphalt mixtures for road surfacing.
SIMULATION STUDY ON THE ELECTRICAL PERFORMANCE OF EQUILIBRIUM THIN-BODY DOUBLE-GATE NANO-MOSFET
Authors: Ooi Chek Yee , Soo King Lim
Published: September 2015

This paper presents a numerical simulation study for electrical characteristics of double-gate (DG) nano-MOSFET at equilibrium thin-body condition. The electrical characteristics which are studied include subband energy (including unprimed and primed subbands), 2D electron density at 77K and 300K ambient temperatures, transmission coefficient, average electron velocity and ballistic current. The ranges of silicon body thickness TSi are 1.0 nm, 1.5 nm and 2.0 nm. The electron transport models used in simulation tool covered quantum model and classical model. Simulation output data are also compared with theoretical discussion.
MODELING OF VIOLENT CRIME RATES WITH ECONOMIC INDICATORS USING HYBRIDIZATION OF GREY RELATIONAL ANALYSIS AND SUPPORT VECTOR REGRESSION
Authors: Alwee Razana , Shamsuddin Siti Mariyam , Sallehuddin Roselina
Published: September 2015

Regression and econometric models are commonly applied in modeling of violent crime rates. However, these models are mainly linear and only capable in modeling linear relationships. Moreover, the econometric models are quite complex to develop. Although time series model is a promising alternative tool, limited historical data of crime rates makes the standard time series models less suitable for modeling the violent crime rates. Thus, in this study, a hybrid model that can handle limited historical data is proposed for modeling the violent crime rates. The proposed hybrid model combines grey relational analysis and support vector regression. Since inaccurate parameters setting leads to inaccuracy of support vector regression model, particle swarm optimization is used to increase the accuracy of the model. The proposed hybrid model is used to model the violent crime rates of United State based on economic indicators. The proposed model also has additional features such as able to choose the data series for economic indicators and significant economic indicators for the violent crime rates. The experimental results showed that the proposed model produces more accurate forecast as compared to multiple linear regression in forecasting the violent crime rates.
A PRELIMINARY STUDY ON MOSQUITO LARVICIDAL EFFICACY OF ROTENONE EXTRACTED FROM MALAYSIA Derris sp.
Authors: Zubairi Saiful Irwan , Sarmidi Mohamad Roji , Aziz Ramlan Abd.
Published: September 2015

Rotenone is a bio-active compound extracted from Derris elliptica (locally known as ‘Tuba’ plant). It has long been used as bio-pesticide, which is more environmental friendly than the commercially available pesticides and has the potential to be used in eliminating mosquito larvae. Therefore, the objective of this study is to determine the mosquito larvicidal activity (LC50) through the usage of liquid crude extract of Derris plant root. The rotenone liquid crude extract was extracted using normal soaking extraction (NSE) method. Two different solvent ratios were used to extract rotenone namely: (A) methyl chloride: methanol (1:1) and (B) methyl chloride: methanol (1:9). The extracts were concentrated using rotary evaporator at 40 oC with vacuum pressure of 800 mbar prior to the reverse-phase high performance liquid chromatography analysis (RP-HPLC) and biological activity (LC50) study. Next, the diluted extracts were subjected to the biological activity treatment for 6 hrs. The results showed that the concentrated liquid crude extracts of methyl chloride: methanol (1:1) which contained the highest rotenone content produced the lowest treatment concentration of 0.024 mg/ml to achieve 50% mortality within 3 hrs of treatment (p<0.05). The rapid mortality (as indicated by the LC50 value) of the mosquitoes’ larvae against rotenone extracted from Derris plant roots has proven that it has the potential to be used as larvicide to control vector-borne diseases especially from mosquitoes.
FIBER GLASS COMPOSITE LAMINATES (FGCL) MEASUREMENT USING 3 AXIS PULSE ECHO SCANNING UNIT
Authors: Mahmod Muhammad Faisal , Abu Bakar Elmi , Othman A. R. , Ramzi A. R. , Goh CY
Published: September 2015

Ultrasonic is a common non-destructive testing for composite laminates inspection. However, high cost caused limited budget organization to own this equipment for their research activities. Our work seeks to develop an automated and reliable ultrasonic scanning unit with affordable cost. The validation of scanning speed using Arduino UNO Microcontroller has successfully achieved by determined the stepping mode. This prototype is suggested to inspect surface defect on glass fiber composite laminates up to 6 mm in thickness as the probe limitation for optimum scanning performance. The optimum scanning speed for this prototype was 12 mm/sec using micro step setup while the average percentage of different against ten times inspection are as low as five percent.
GRAPHICAL USER INTERFACE FOR ASSESSING SUSTAINABILITY BY USING FUZZY LOGIC: A CASE STUDY ON HOLLOW FIBER MEMBRANE MODULE
Authors: Mahmood Salwa , Hemdi Abdul Rahman , Mat Saman Muhamad Zameri , Mohd Yusof Noordin
Published: September 2015

An important consideration during product development is the sustainability level of a product. Thus, several tools and methods have been developed to assess product sustainability. However, most of current tools focus only on the environmental element without considering two important sustainability elements such economic and social elements. Other tools are limited to the cradle-to-gate system boundary, which covers two phases of the product life cycle from raw material extraction to the end of the manufacturing stage. Users need to understand the mathematical calculations and tools needed to achieve this purpose. Hence, this paper developed a comprehensive method for assessing the sustainability of product development considering all sustainability elements from cradle-to-grave. A graphical user interface (GUI) was developed for ease of use from the structured methodology. The developed GUI was embedded with the fuzzy logic calculation under the Matlab GUI platform with codes and callback functions by using fuzzy linguistics. The GUI presented is a user friendly assessment since users no need to understand the mathematical equation embedded. A product was selected as a case study to demonstrate the use of the GUI. The sustainability level of a product can be monitored via the GUI to enable further product sustainability improvement.
VHF-PECVD FABRICATION PARAMETERS DEPENDENT MORPHOLOGYVARIATION OF GOLD CATALYST ASSISTED SILICON THIN FILM GROWTH
Authors: Hamzah Khaidzir , Abdullah Izat Mohd Yassin M. , Krishna Ghoshal Sib , Hasanudin M. Akmal , Ismail Abdul Khamim
Published: September 2015

Achieving two dimensional quantum structure of silicon with well-defined tunable morphology is an outstanding issue. We present the preliminary results on fabrication parameters dependent silicon thin film production using VHF-PECVD method. Five samples are prepared on Si(100) substrate with gold (Au) catalyst by adjusting different parameters such as deposition time, temperature and the flow of precursor gas. The samples morphology are analyzed using FESEM. The results reveal that the silicon thin film appear to be smooth and more uniform after an enormous amount of hydrogen is inserted together with the precursor gas (silane) during the deposition process. More interestingly, the films exhibit silicon nanowires as the deposition time is increased up to 1 hour. This morphological transformation is attributed to the vapor-liquid-solid (VLS) mechanism related to the deposition process.
SPECTRAL CLUSTERING ON GENE EXPRESSION PROFILE TO IDENTIFY CANCER TYPES OR SUBTYPES
Authors: Jun Chin Ang , Mirzal Andri , Haron Habibollah
Published: September 2015

Gene expression profile is eminent for its broad applications and achievements in disease discovery and analysis, especially in cancer research. Spectral clustering is robust to irrelevant features which are appropriated for gene expression analysis. However, previous works show that performance comparison with other clustering methods is limited and only a few microarray data sets were analyzed in each study. In this study, we demonstrate the use of spectral clustering in identifying cancer types or subtypes from microarray gene expression profiling. Spectral clustering was applied to eleven microarray data sets and its clustering performances were compared with the results in the literature. Based on the result, overall the spectral clustering slightly outperformed the corresponding results in the literature. The spectral clustering can also offer more stable clustering performances as it has smaller standard deviation value. Moreover, out of eleven data sets the spectral clustering outperformed the corresponding methods in the literature for six data sets. So, it can be stated that the spectral clustering is a promising method in identifying the cancer types or subtypes for microarray gene expression data sets.
PREDICTION OF PADDY IRRIGATION REQUIREMENTS BY USING STATISTICAL DOWNSCALING AND CROPWAT MODELS: A CASE STUDY FROM THE KERIAN IRRIGATION SCHEME IN MALAYSIA
Authors: Hamidon Nuramidah , Harun Sobri , Malek M. A , Ismail Tarmizi , Alias Noraliani
Published: September 2015

With an average rainfall of 2500mm per year, Malaysia has abundant water resources but climate change coupled with drought, urbanisation and pollution sometimes causes water stress. Global warming has changed the local climate, threatening agricultural activities with particular impact on paddy production systems. To ensure availability of sufficient irrigation water for growing crops, there is a need to estimate future irrigation water requirements in the face of the complex dynamic resulting from global warming. The current study was therefore carried out to estimate paddy irrigation water requirements based on future climate trends by using SDSM and CROPWAT Models at the Kerian Irrigation Scheme, Perak, Malaysia. The application of the SDSM model revealed that both temperature and rainfall will increase in the future. Meanwhile the CROPWAT model predicted that the annual irrigation requirement will slightly decrease for period between 2010-2069 and increase for years 2070-2099 even though crop evapotranspiration (ETcrop) is predicted to increase in future for rise in temperature for year 2010 to 2099. This integration of SDSM and CROPWAT models produced better simulations of crop water requirement and irrigation requirement. Therefore, it can assist the reservoir’s operating management team in giving effective and proficient response to climate changes in the future.
A SURVEY ON SELF-ORGANIZED CLUSTER-BASED WIRELESS SENSOR NETWORK
Authors: Zeb Asim , Islam A. K. M. Muzahidul , Baharun Sabariah , Mansoor Nafees , Katayama Yoshiaki
Published: September 2015

Study on Wireless Sensor Network (WSN) has been expended enormously in recent years. Sensor nodes are deployed in harsh environment which is operated autonomously. Network formation of WSNs are of two types, namely flat network and cluster-based network. Cluster-based network has various advantages as compare to flat network such as, efficient topology management, energy efficiency, minimized delay, better network communication, etc. Another important feature of cluster-based network is self-organized network. Self-organized enables new nodes joining to increase the coverage of the network and existing nodes leaving the network as node have limited energy. In recent years the demand of self-organized network is tremendously increasing to overcome the problem of node joining and leaving which maintain the smooth data communication. Thus, this survey addresses latest research works regarding self-organized cluster-based network. Moreover, a unique performance matrix is also investigated in this article to measure the algorithms. Finally, open research issues are highlighted for self-organized clustering schemes that might be future line of action.
INVESTIGATION OF TORSIONAL DEFLECTION AS AN UNDESIRED MOTION IN ATOMIC FORCE MICROSCOPY WITH SIDEWALL PROBE
Authors: Mokhtarinezhad Farzad , Rahman Roslan Abd. , Eftekhar Sina , Sadegh Hassani Sedigheh
Published: September 2015

In this paper an analytical model is presented for the Micro-Cantilever (MC) of Atomic Force Microscopy with Side Wall probe (AFM-SW) in the tapping excitation mode. In this model the couple motion of the MC is taken into account while the torsional motion is considered as an undesirable motion which is coupled with the vertical motion. To this end, the effect of several parameters, namely; probe mass, probe dislocation, sidewall extension length, and tip sample interaction force is investigated on the occurrence probability of torsional and vertical motions. It is found that the probe dislocation is the prerequisite factor of the undesired motion happening. For sake of validation, the analytical results are compared against the previously published results, and an excellent agreement is observed.
PENENTUAN SIFAT KEKUKUHAN DAN KETEBALAN LAPISAN PERMUKAAN BERASFALT MENGGUNAKAN KAEDAH PENCARIAN RESONAN TAMBAHAN (ERS)
Authors: Zakaria Nur Mustakiza , Md. Jaffary Muhammad Fakhry , Hassan Muhammad Kamal , Hamim Asmah , Md. Yusoff Nur Izzi , Mohd Nayan Khairul Anuar
Published: September 2015

This study was conducted to investigate the stiffness and thicknesses of asphalt surface layer using the Enhance Resonance Search (ERS) technique. A total of fifteen locations in the Universiti Kebangsaan Malaysia (UKM) Campus have been identified to carry out this experiment. The results were then compared with standards provided by the Malaysian Public Works Department (PWD), Jabatan Pembangunan dan Penyelenggaraan (JPP) UKM and Kumpulan IKRAM Sdn. Bhd. The computation found that the range of elastic moduli values of asphalt layer is between 3928.877 and 17726.012 MPa. A comparison between the experiment results and JPP UKM standard on pavement thickness showed that the different is between 20% to 60%, with the average thickness of 44.13 mm.  However, the average value of thickness is still in good agreement with the JKR and JPP UKM standards. Some stiffness values obtained are higher than the standard, probably due to the quality of materials used, the influence of the traffic load and the age of the pavement construction.
ENHANCEMENT OF CONTROL’S PARAMETER OF DECOUPLED HVAC SYSTEM VIA ADAPTIVE CONTROLLER THROUGH THE SYSTEM IDENTIFICATION TOOL BOX
Authors: Attaran Seyed Mohammad , Yusof Rubiyah
Published: September 2015

Heating, Ventilating and Air Conditioning (HVAC) systems have nonlinear character and nature. Current models for control components and the optimization of HVAC system parameters can be linear approximations based on an operating or activation point, or alternatively, highly complex nonlinear estimations. This duality creates problems when the systems are used with real time applications. The two parameters temperature and relative humidity (RH) have a more direct effect in most applications of HVAC systems than the execution. This study’s objective is to implement and simulate an adaptive controller for decoupled bi-linear HVAC systems for the purpose of controlling the temperature and RH in a thermal zone. The contribution of this study is to apply the adaptive controller for the decoupled bi linear HVAC system via relative gain array (RGA). To achieve this objective, we used a system identification toolbox to increase the speed and accuracy of the identification of system dynamics, as was required for simplification and decoupled HVAC systems. The method of decoupling is relative gain array. The results of the simulation show that when compared with a classical PID controller, the adaptive controller performance is superior, owing to the high efficiency with which the steady state set points for temperature and RH are reached.
Étude on Gas Turbine Combined Cycle Power Plant—Next 20 Years
Authors: Can Gülen S.
Published: September 2015

In 1992, United States Department of Energy's (DOE) Advanced Turbine Systems (ATS) program established a target of 60% efficiency for utility scale gas turbine (GT) power plants to be achieved by the year 2000. Although the program led to numerous technology breakthroughs, it took another decade for an actual combined cycle (CC) power plant with an H class GT to reach (and surpass) the target efficiency. Today, another target benchmark, 65% efficiency, circulates frequently in trade publications and engineering journals with scant support from existing technology, its development path as well as material limits, and almost no regard to theoretical (e.g., underlying physics) and practical (e.g., cost, complexity, reliability, and constructability) concerns. This paper attempts to put such claims to test and establish the room left for gas turbine combined cycle (GTCC) growth in the next two decades. The analysis and conclusions are firmly based on fundamental thermodynamic principles with carefully and precisely laid out assumptions and supported by rigorous calculations. The goal is to arm the practicing engineer with a consistent, coherent, and self-standing reference to critically evaluate claims, predictions, and other futuristic information pertaining to GTCC technology.
Impact of Delays for Electric Vehicles With Direct Yaw Moment Control
Authors: Li Yanjun , Yin Guodong , Jin XianJian , Bian Chentong , Li Jianqiu
Published: September 2015

This paper investigates the impact of time delay factors on the lateral motion of electric vehicles with direct yaw moment control (DYC). The existence of internal time delay factors is inescapable in electric vehicle (EV) systems, which might affect the effectiveness of DYC. Computer simulation shows that DYC works well at small time delays, while significant oscillation or even loss of stability occurs when the delays are large enough. A frequency-domain method is used to determine the stability limit of the time-delayed system.
Interaction-Induced Morphological Transitions of Lipid Membranes in Contact With an Elliptical Cross Section of a Rigid Substrate
Authors: Belay T. , Kim C. I. , Schiavone P.
Published: September 2015

We present a complete analysis for the deformation profiles of lipid membranes induced by their interactions with solid elliptical cylinder substrates (e.g., proteins). The theoretical framework for the mechanics of lipid membranes is described in terms of the classical Helfrich model, and the resulting shape equation is formulated in general curvilinear coordinates to accommodate the elliptical shape of the contour surrounding the contact area. Admissible boundary conditions for the contact region are taken from the existing literature but reformulated and adapted to the current framework. A complete semi-analytic solution (in terms of Mathieu functions) is obtained within the limitation of superposed incremental deformations and the Monge representation in the deformed configuration functions. The results predict smooth morphological transitions over the domain of interest when a lipid membrane interacts with a rigid substrate through an elliptical contact region.
A New Efficient System Identification Method for Nonlinear Multiple Degree-of-Freedom Structural Dynamic Systems
Authors: Guo Yuzhu , Guo L. Z. , Billings S. A. , Lang Z. Q.
Published: September 2015

A new efficient system identification method is introduced to determine the model structure and parameter estimates of an unknown structural system to produce a multi-input multi-output (MIMO) model. No a priori knowledge is assumed regarding the nonlinearities. When the system involves lumped masses, all the information about the locations, types, and coefficients of both linear and nonlinear links which connect the lumped masses in the system can be determined in one efficient procedure. The new algorithm yields a parsimonious continuous time model which is useful for the interpretation of the system in practical applications. An illustrative example demonstrates the efficiency of the new method.
Ferromagnetic, spin glass, and antiferromagnetic behaviors in Cd1−xMnxTe nanowires
Authors: Sapkota Keshab R. , Dulal Rajendra , Dahal Bishnu R. , Pegg Ian L. , Philip John
Published: September 2015

The Cd1−xMnxTe (x = 0–0.18) nanowires were grown using a wet-chemical synthesis. The synthesized Cd1−xMnxTe nanowires have diameters in the range of 50–100 nm and display zinc-blend crystal structure. In bulk, Cd1−xMnxTe is extensively studied, but the difficulty in doping Mn in CdTe nanowires delayed the understanding of the properties at the nanoscale. The authors have used a cation exchange method to incorporate Mn in CdTe nanowires. Their magnetic behavior can be tuned by varying the concentration of Mn ions. The CdTe nanowires were paramagnetic while doping small amount of Mn ions introduces ferromagnetic behavior at low temperatures. As the manganese concentration is increased in CdTe, both spin glass and antiferromagnetic behaviors are observed. This is in contrast to what is observed in bulk, where only paramagnetic behavior is observed for x < 0.17.
Objective assessment in digital images of skin erythema caused by radiotherapy
Authors: Matsubara H. , Matsufuji N. , Tsuji H. , Yamamoto N. , Karasawa K. , Nakajima M. , Takahashi W. , Karube M.
Published: September 2015

Purpose:

Skin toxicity caused by radiotherapy has been visually classified into discrete grades. The present study proposes an objective and continuous assessment method of skin erythema in digital images taken under arbitrary lighting conditions, which is the case for most clinical environments. The purpose of this paper is to show the feasibility of the proposed method.

Methods:

Clinical data were gathered from six patients who received carbon beam therapy for lung cancer. Skin condition was recorded using an ordinary compact digital camera under unfixed lighting conditions; a laser Doppler flowmeter was used to measure blood flow in the skin. The photos and measurements were taken at 3 h, 30, and 90 days after irradiation. Images were decomposed into hemoglobin and melanin colors using independent component analysis. Pixel values in hemoglobin color images were compared with skin dose and skin blood flow. The uncertainty of the practical photographic method was also studied in nonclinical experiments.

Results:

The clinical data showed good linearity between skin dose, skin blood flow, and pixel value in the hemoglobin color images; their correlation coefficients were larger than 0.7. It was deduced from the nonclinical that the uncertainty due to the proposed method with photography was 15%; such an uncertainty was not critical for assessment of skin erythema in practical use.

Conclusions:

Feasibility of the proposed method for assessment of skin erythema using digital images was demonstrated. The numerical relationship obtained helped to predict skin erythema by artificial processing of skin images. Although the proposed method using photographs taken under unfixed lighting conditions increased the uncertainty of skin information in the images, it was shown to be powerful for the assessment of skin conditions because of its flexibility and adaptability.
Modeling of thermoacoustic systems using the nonlinear frequency domain method
Authors: de Jong J. A. , Wijnant Y. H. , Wilcox D. , de Boer A.
Published: September 2015

When modeling thermoacoustic (TA) devices at high amplitude, nonlinear effects such as time-average mass flows, and the generation of higher harmonics can no longer be neglected. Thus far, modeling these effects in TA devices required a generally computationally costly time integration of the nonlinear governing equations. In this paper, a fast one-dimensional nonlinear model for TA devices is presented, which omits this costly time integration by directly solving the periodic steady state. The model is defined in the frequency domain, which eases the implementation of phase delays due to viscous resistance and thermoacoustic heat exchange. As a demonstration, the model is used to solve an experimental standing wave thermoacoustic engine. The obtained results agree with experimental results, as well as with results from a nonlinear time domain model from the literature. The low computational cost of this model opens the possibility to do optimization studies using a nonlinear TA model.
The E3 ligase APC/C
Cdh1
promotes ubiquitylation-mediated proteolysis of PAX3 to suppress melanocyte proliferation and melanoma growth
Authors: Cao Juxiang , Dai Xiangpeng , Wan Lixin , Wang Hongshen , Zhang Jinfang , Goff Philip S. , Sviderskaya Elena V. , Xuan Zhenyu , Xu Zhixiang , Xu Xiaowei , Hinds Philip , Flaherty Keith T. , Faller Douglas V. , Goding Colin R. , Wang Yongjun , Wei Wenyi , Cui Rutao
Published: September 2015

Loss of a ubiquitin ligase promotes melanoma growth.
GS-5806 Inhibits Pre- to Postfusion Conformational Changes of the Respiratory Syncytial Virus Fusion Protein
Authors: Samuel Dharmaraj , Xing Weimei , Niedziela-Majka Anita , Wong Jinny S. , Hung Magdeleine , Brendza Katherine M. , Perron Michel , Jordan Robert , Sperandio David , Liu Xiaohong , Mackman Richard , Sakowicz Roman
Published: September 2015

GS-5806 is a small-molecule inhibitor of human respiratory syncytial virus fusion protein-mediated viral entry. During viral entry, the fusion protein undergoes major conformational changes, resulting in fusion of the viral envelope with the host cell membrane. This process is reproduced
in vitro
using a purified, truncated respiratory syncytial virus (RSV) fusion protein. GS-5806 blocked these conformational changes, suggesting a possible mechanism for antiviral activity.
Artemisinin Resistance at the China-Myanmar Border and Association with Mutations in the K13 Propeller Gene
Authors: Wang Zenglei , Wang Yingna , Cabrera Mynthia , Zhang Yanmei , Gupta Bhavna , Wu Yanrui , Kemirembe Karen , Hu Yue , Liang Xiaoying , Brashear Awtum , Shrestha Sony , Li Xiaolian , Miao Jun , Sun Xiaodong , Yang Zhaoqing , Cui Liwang
Published: September 2015

Artemisinin resistance in
Plasmodium falciparum
parasites in Southeast Asia is a major concern for malaria control. Its emergence at the China-Myanmar border, where there have been more than 3 decades of artemisinin use, has yet to be investigated. Here, we comprehensively evaluated the potential emergence of artemisinin resistance and antimalarial drug resistance status in
P. falciparum
using data and parasites from three previous efficacy studies in this region. These efficacy studies of dihydroartemisinin-piperaquine combination and artesunate monotherapy of uncomplicated falciparum malaria in 248
P. falciparum
patients showed an overall 28-day adequate clinical and parasitological response of >95% and day 3 parasite-positive rates of 6.3 to 23.1%. Comparison of the 57 K13 sequences (24 and 33 from day 3 parasite-positive and -negative cases, respectively) identified nine point mutations in 38 (66.7%) samples, of which F446I (49.1%) and an N-terminal NN insertion (86.0%) were predominant. K13 propeller mutations collectively, the F446I mutation alone, and the NN insertion all were significantly associated with day 3 parasite positivity. Increased ring-stage survival determined using the ring-stage survival assay (RSA) was highly associated with the K13 mutant genotype. Day 3 parasite-positive isolates had ∼10 times higher ring survival rates than day 3 parasite-negative isolates. Divergent K13 mutations suggested independent evolution of artemisinin resistance. Taken together, this study confirmed multidrug resistance and emergence of artemisinin resistance in
P. falciparum
at the China-Myanmar border. RSA and K13 mutations are useful phenotypic and molecular markers for monitoring artemisinin resistance.
Greater Ciprofloxacin Tolerance as a Possible Selectable Phenotype Underlying the Pandemic Spread of the
H
30 Subclone of Escherichia coli Sequence Type 131
Authors: Johnson James R. , Porter Stephen B. , Thuras Paul , Johnson Timothy J. , Price Lance B. , Tchesnokova Veronika , Sokurenko Evgeni V.
Published: September 2015

Minimum bactericidal concentrations (MBCs) for ciprofloxacin were significantly higher among 41 members of the
H
30 subclone within
Escherichia coli
sequence type 131 than among 48 other fluoroquinolone-resistant
E. coli
isolates. This MBC difference, which was not explained by ciprofloxacin MICs,
gyrA
,
parC
, and
parE
mutations, the presence of
aac
(
6
′)-
Ib-cr
, or organic solvent tolerance (a surrogate for efflux pump activity), conceivably could have promoted the pandemic emergence of the
H
30 sequence type 131 subclone.
Functions of a GyrBA Fusion Protein and Its Interaction with QnrB and Quinolones
Authors: Chen Chunhui , Villet Regis , Jacoby George A. , Hooper David C.
Published: September 2015

In order to study the interactions between
Escherichia coli
DNA gyrase and the gyrase interacting protein QnrB
in vivo
, we constructed a
gyrB-gyrA
fusion and validated its ability to correct the temperature-sensitive growth of
gyrA
and
gyrB
mutants. Like wild-type
gyrA
, the
gyrB-gyrA
fusion complemented a quinolone-resistant
gyrA
mutant to increase susceptibility. It functioned as an active type II topoisomerase, catalyzed negative supercoiling of DNA, was inhibited by quinolone, and was protected by QnrB.
In Vivo
Curative and Protective Potential of Orally Administered 5-Aminolevulinic Acid plus Ferrous Ion against Malaria
Authors: Suzuki Shigeo , Hikosaka Kenji , Balogun Emmanuel O. , Komatsuya Keisuke , Niikura Mamoru , Kobayashi Fumie , Takahashi Kiwamu , Tanaka Tohru , Nakajima Motowo , Kita Kiyoshi
Published: September 2015

5-Aminolevulinic acid (ALA) is a naturally occurring amino acid present in diverse organisms and a precursor of heme biosynthesis. ALA is commercially available as a component of cosmetics, dietary supplements, and pharmaceuticals for cancer diagnosis and therapy. Recent reports demonstrated that the combination of ALA and ferrous ion (Fe
2+
) inhibits the
in vitro
growth of the human malaria parasite
Plasmodium falciparum
. To further explore the potential application of ALA and ferrous ion as a combined antimalarial drug for treatment of human malaria, we conducted an
in vivo
efficacy evaluation. Female C57BL/6J mice were infected with the lethal strain of rodent malaria parasite
Plasmodium yoelii
17XL and orally administered ALA plus sodium ferrous citrate (ALA/SFC) as a once-daily treatment. Parasitemia was monitored in the infected mice, and elimination of the parasites was confirmed using diagnostic PCR. Treatment of
P. yoelii
17XL-infected mice with ALA/SFC provided curative efficacy in 60% of the mice treated with ALA/SFC at 600/300 mg/kg of body weight; no mice survived when treated with vehicle alone. Interestingly, the cured mice were protected from homologous rechallenge, even when reinfection was attempted more than 230 days after the initial recovery, indicating long-lasting resistance to reinfection with the same parasite. Moreover, parasite-specific antibodies against reported vaccine candidate antigens were found and persisted in the sera of the cured mice. These findings provide clear evidence that ALA/SFC is effective in an experimental animal model of malaria and may facilitate the development of a new class of antimalarial drug.
Arsenic Trioxide Negatively Affects Echinococcus granulosus
Authors: Wang Bo , Jiang Yufeng , Wang Zhuo , Li Fangfang , Xing Guoqiang , Peng Xinyu , Zhang Shijie , Lv Hailong
Published: September 2015

Spillage of cyst contents during surgery is the major cause of recurrences of hydatidosis, also called cystic echinococcosis (CE). Currently, many scolicidal agents are used for inactivation of the cyst contents. However, due to complications in the use of those agents, new and more-effective treatment options are urgently needed. The aim of this study was to investigate the
in vitro
efficacy of arsenic trioxide (ATO) against
Echinococcus granulosus
protoscolices. Protoscolices of
E. granulosus
were incubated
in vitro
with 2, 4, 6, and 8 μmol/liter ATO; viability of protoscolices was assessed daily by microscopic observation of movements and 0.1% eosin staining. A small sample from each culture was processed for scanning and transmission electron microscopy. ATO demonstrated a potent ability to kill protoscolices, suggesting that ATO may represent a new strategy in treating hydatid cyst echinococcosis. However, the
in vivo
efficacy and possible side effects of ATO need to be explored.
EepR Mediates Secreted-Protein Production, Desiccation Survival, and Proliferation in a Corneal Infection Model
Authors: Brothers Kimberly M. , Stella Nicholas A. , Romanowski Eric G. , Kowalski Regis P. , Shanks Robert M. Q.
Published: September 2015

Serratia marcescens
is a soil- and water-derived bacterium that secretes several host-directed factors and causes hospital infections and community-acquired ocular infections. The putative two-component regulatory system composed of EepR and EepS regulates hemolysis and swarming motility through transcriptional control of the
swrW
gene and pigment production through control of the
pigA
-
pigN
operon. Here, we identify and characterize a role for EepR in regulation of exoenzyme production, stress survival, cytotoxicity to human epithelial cells, and virulence. Genetic analysis supports the model that EepR is in a common pathway with the widely conserved cyclic-AMP receptor protein that regulates protease production. Together, these data introduce a novel regulator of host-pathogen interactions and secreted-protein production.
Role of the Tet38 Efflux Pump in Staphylococcus aureus Internalization and Survival in Epithelial Cells
Authors: Truong-Bolduc Q. C. , Bolduc G. R. , Medeiros H. , Vyas J. M. , Wang Y. , Hooper D. C.
Published: September 2015

We previously identified the protein Tet38 as a chromosomally encoded efflux pump of
Staphylococcus aureus
that confers resistance to tetracycline and certain unsaturated fatty acids. Tet38 also contributes to mouse skin colonization. In this study, we discovered a novel regulator of
tet38
, named tetracycline regulator 21 (TetR21), that bound specifically to the
tet38
promoter and repressed pump expression. A Δ
tetR21
mutant showed a 5-fold increase in
tet38
transcripts and an 8-fold increase in resistance to tetracycline and fatty acids. The global regulator MgrA bound to the
tetR21
promoter and indirectly repressed the expression of
tet38
. To further assess the full role of Tet38 in
S. aureus
adaptability, we tested its effect on host cell invasion using A549 (lung) and HMEC-1 (heart) cell lines. We used
S. aureus
RN6390, its Δ
tet38
, Δ
tetR21
, and Δ
mgrA
mutants, and a Δ
tet38 ΔtetR21
double mutant. After 2 h of contact, the Δ
tet38
mutant was internalized in 6-fold-lower numbers than RN6390 in A549 and HMEC-1 cells, and the Δ
tetR21
mutant was internalized in 2-fold-higher numbers than RN6390. A slight increase of 1.5-fold in internalization was found for the Δ
mgrA
mutant. The growth patterns of RN6390 and the Δ
mgrA
and Δ
tetR21
mutants within A549 cells were similar, while no growth was observed for the Δ
tet38
mutant. These data indicate that the Tet38 efflux pump is regulated by TetR21 and contributes to the ability of
S. aureus
to internalize and replicate within epithelial cells.