Duplex surface process was developed to deposite thin ceramic film coating on commonly manufacturing used low alloy steels. Low alloy steel having low strength by this process was first plasma nitrided with purpose enhancing load bearing capacity and then deposited with such ceramic coating. In this study, the duplex surface treatment was deal with main lines and informed about advantage and disadvantage.

Mechanical properties of some aluminum alloys can be changed with precipitation hardening. This intermetallic precipitates are incoherent with the main structure and increased mechanical properties. Cooling rates after solid solution process effects properties after precipitation. In applications, however this is not taken into consideration. In this study, AA 2014 and AA 2024 Aluminium Alloy specimens were hold for one hour at 495±3 0C and formed a solid solution. Specimens were quenched at this temperature with different cooling rtes . later artificial aging was applied at 150 0C and 180 0C. The hardness and microstructure variations of the specimens were investigated depending on the cooling rates and artificial aging temperatures.

This study presents the heat transfer enhancement in the thermal energy storage system by using radially finned tube. The solution of the system consists of the solving the equations of the heat transfer fluid (HTF), the pipe wall and fin, and the phase change material (PCM) as one domain. The control volume finite difference approach and the semi implicit solver (SIS) are used to solve the equations. Fully developed velocity distribution is taken in the HTF. Flow parameters (Re number and inlet temperature of coolant) and fin parameters (the number of fins, fin length, fin thickness) are found to influence solidification fronts and the total stored energy.

In this study, the various thermal comfort parameters including temperature, relative humidity, air velocity, metabolic activity and clothing resistance and their effect to each other are examined. The heat transfer equations given for steady state energy balance between body and environment and the empirical equations which give thermal comfort and physiological control mechanisms of body are used. According to the ASHRAE Standard 55-1992, an environment can be assumed comfortable while Predicted Percentage of Dissatisfied (PPD) is less than % 10. Considering this, thermal comfort zones in various conditions are studied and results are presented and discussed

In this paper; spur gears made from graphite epoxy normal and shear stresses are examined. The stresses of super gears are calculated from outer to interior defines in tree zones for different fibers reinforcement angles. Three dimensionel finite element model (FEM) used in this study. Eight noded three dimensionel izoparemetric elements are chosen as finite element method. Normal and shear stresses are calculated in differrent fiber orientatýons and ploted in graphs. The results of plotted graphies are examinated.

Recently, there is a high interest in using lightweight materials for automotive applications where weight reduction and improvement in comfort are needed. Magnesium alloys with excellent specific strength and stiffness properties can be comparable with steel and aluminum alloys for applications in the automotive industry. For this reason, the properties of magnesium alloys are in the focus of research. This study aims at reviewing and evaluating the prospects of magnesium alloys use and applications in the automotive industry.

In a very near future, as a result of the continious growth of Internet and advances in networking technologies, Internet will become the common software repository for people and organizations who employ component based reuse approach in their software development life cycles. In order to use the reusable components such as source codes, analysis, designs, design patterns during new software development processes, environments that support the identification of the components over Internet are needed. Basic elements of such an environment are the coordinator programs which deliver user requests to appropriate component libraries, user interfaces for querying, and programs that wrap the component libraries. First, a CORBA based architecture is proposed for such an environment. Then, an alternative architecture that is based on the Java 2 platform technologies is given for the same environment. Finally, the two architectures are compared.

In this paper, Application Programming Interfaces (API) which are used for graphics software development are classified and introduced briefly. Properties of 2D and 3D API’s are specified. Programs which are implemented in this study (Kup3B Java2D version, Kup3B Java3D version) are compared by number of lines of code written. Charts are constructed by using values obtained and interpreted.

In this paper, the moment resisting frames which are commonly used on the steel structures are summerized. The moment resisting steel frames which are constructed with different shapes are classified according to the configuration of moment frame, the type of connectors used, the ductility of connection, the relative rotational stiffness of the connection and members and the relative moment capacity of the connection and members

In the aftermath of massive earthquakes in 1999, the use of sea sand in the construction material as a substance has been widely questioned as it may have negative side effects on endurance strength of buildings in coastal cities. In this study, the change in the endurance of the concrete has been tested by the use of sea and river sand types from Zonguldak-Alapli region. Some experiments concerning unit weights, absolute weights, and ratio of fine material and organic material ratio of sand types were also executed. As a result of experiment made about special features of the sand types, it is well understood that the endurance strength of concrete consisting of sea sand is 34% less than that of the normal sand due to the changes in ingredients of sand types.

Flavour is the main factor determining the purchase of food and it also effects to consumer preferences. Therefore, flavour problems usually come to light as a result of consumers’ complaints, and flavour defects in food are a major cause of consumer rejection of the food product including milk and milk products. Flavour and off-flavour in milk and milk products have been the subject of active research in the last decade; there have been developments in the analytical techniques used to monitor flavour development, flavour and off-flavour compounds in many dairy product have now been investigated. The chemicals responsible for unacceptable flavours in milk and milk products can originate incidental contamination from environmental sources, from animal feeding, from chemical reactions occuring within the food material itself and from other sources. The objectives of this paper comprise, after definitions, summarizing the possible sources and specific compounds of off-flavours, and discussing different approaches for off-flavour concept in milk and dairy products.

Polyethylene terephthalate (PET) is one of the most used thermo-plastic polymers. The total consumption of PET has been about 30 million tons in the year 2000. Polyester fibers constitute about 60 % of total synthetic fibers consumption. During extrusion, PET polymer is faced to thermal, thermo-oxidative and hydrolytic degradation, which result in severe reduction in its molecular weight, thereby adversely affecting its subsequent melt processability. Therefore, it is essential to understand degradation processes of PET during melt extrusion.

On this paper, the analysis of working system of doffer used on OE spinning and packaging machines are studied. In addition, the mathematics model of relation between working parameters of the doffer and technological parameters of machines were obtained. The evaluating “useful time coefficient” of performance on doffer is determined. During the research, the two working systems obtained saving of electrical energy as improving the performance of doffer such as “waiting-working” and “working by signals” was suggested.

The project “High Speed Dobby Design for Weaving Machines” with the number of MÝSAG-139, which wascarried out the Textile Department of Engineering Faculty at Pamukkale University between the dates 10.08.1999 – 01.08.2001, was successfully completed and approved by TÜBÝTAK (The Scientific and Technical Research Council of Turkey). The first part of the paper includes a classification and analysis of dobby machines; besides the information obtained from patent application is included.

Investigations to develop data for this study were made using a pilot scale glass column of 9 cm inside diameter randomly filled to a depth of 1.90 cm with a Raschig type ring at a slightly modified geometry. The geometrical characteristics of packing are: the total area of a single particle ad = 2.3 cm2; specific area ap = 10.37 cm2/cm3; voidage ? = 0.545 m3/m3. The efficiency tests were run using trichloroethylene/n-heptane system under total reflux conditions. Using the modified versions of the Eckert flooding model and the Bravo effective area (ae) approach, as well as the Onda wetted area (aw) and individual mass transfer coefficient models, it has been attempted to estimate the packing efficiency theoretically. This article also deals with the design strategies attributed to a randomly packed column. Emphasis is mainly placed on the way to formulate an algorithm of designing a pilot scale column through the models being attributed to the film theory. Using the column dry pressure drop properties based on the air flowing it has been achieved a generalized flow rate approach for calibrating of an orifice through which the air passes.

The liquid-liquid equilibria of Water-Propionic Acid-Benzyl Alcohol, Water-Propionic Acid-Benzyl Acetate and Water-Propionic Acid-Dibenzyl Ether ternary systems were predicted by means of UNIFAC Model. For this purpose, multivariable Newton-Raphson convergence procedure was used. Experimental and model results were compared.

This paper deals with the stability of the boundary element method. The effects of various element sizes and time increments on the internal solution are analyzed. To this end, a time domain boundary element method is used. To achieve this, an existing BEM code for the boundary nodes is modified to optional internal nodes. Using appropriate time and spatial variations for the field variables, some observations on the numerical stability are reported. The internal solutions are presented for different ß values and discussed the reasons of unstable cases appeared.

The main factor for furniture manufacturing with box construction is diagonal compression or diagonal tensile strength on joint points. This strength differences according to type of wooden board joining style an glue type.In this study, the effects of lathly joining with different glue type on the different wooden board in box construction manufacturing was experimentally tested by diagonal compression and tensile test methods. Finally, it was determined that the diagonal compression and tensile strengths were lower in all lathly joining wooden board with used polyviniyl acetat glue and those were higer with used desmodur-vtka glue.