bluuebunny/crossref_metadata_2025 huggingface dataset:
A NEW APPRECIATION OF THE MEMOIR OF CARNOT
Authors: POTTER J. H.
Published: August 2010

In the English translations of the original memoir of Carnot the words “feu,” “chaleur” and “calorique” were each considered as equivalent to “heat.” Brønsted and La Mer claim that “calorique” may have been intended as the property we now identify as “entropy.” To date there has been no engineering study of the consequences of the new interpretation of Carnot's “calorique.” An analysis is offered to show the effects of this substitution in the memoir.
THE MAXIMUM PRESSURES AND TOTAL FORCE ON STRAIGHT‐SIDED WEDGES WITH SMALL DEADRISE
Authors: BORG S. F.
Published: August 2010

A new theory for solving wedge‐entry problems is utilized to give an approximate solution for the pressures and forces acting on blunt (small deadrise angle) straight sided wedges. Closed form analytical expressions are given for the maximum pressures, pressure at any point and total vertical force acting on a blunt symmetrical wedge entering an infinite ocean at constant vertical velocity.
Peripheral Versus Central Muscarinic Effects on Blood Pressure, Cardiac Contractility, Heart Rate, and Body Temperature in the Rat Monitored by Radiotelemetry
Authors: Smith Edward G. , Padnos Beth , Gordon Christopher J.
Published: August 2010

Abstract: Our laboratory has found that the organophosphate pesticide chlorpyrifos elicits an elevation in blood pressure that persists for ∼24 hr after exposure. Since organophosphate pesticides inhibit acetylcholinesterase activity and cause cholinergic stimulation in the central nervous system and peripheral tissues, we suspect that the hypertensive response from chlorpyrifos is elicited by activation of pressor areas in the brain stem, specifically muscarinic receptors which are known to mediate hypertensive responses. Oxotremorine, a muscarinic agonist, should elicit a blood pressure response similar to organophosphate pesticides. This study used radiotelemetry to assess the effects of oxotremorine on blood pressure, heart rate, core temperature, QA interval (a measure of cardiac contractility), and motor activity in the male, Long‐Evans rat. Subcutaneous co‐administration of 0.2 mg/kg oxotremorine with 1.0 mg/kg methyl scopolamine (i.e., to block oxotremorine’s peripheral effects) caused a marked elevation in blood pressure that developed concomitantly with a 2 ° decrease in core temperature, 60 beats/min. increase in heart rate, increase in cardiac contractility but no change in motor activity. Overall, blood pressure increased by 19 mmHg from baseline and the response persisted for ∼12 hr after injection. Methyl scopolamine alone increased heart rate but had no effect on blood pressure, core temperature, and motor activity. Oxotremorine injected without methyl scopolamine led to a relatively minor increase in blood pressure and hypothermia. Overall, central muscarinic stimulation with oxotremorine and methyl scopolamine leads to a vigorous hypertensive response that is associated with increased cardiac contractility, suggesting an increase in cardiac output. Combined central and peripheral cholinergic stimulation following oxotremorine without methyl scopolamine, as would also occur with exposure to chlorpyrifos and other organophosphate pesticides, did not elicit as much of a hypertensive response. This would suggest pathways other than those controlled directly with muscarinic receptors are operative in the development of chlorpyrifos‐induced hypertension.
Increased Plasma Endothelin‐1 and Cardiac Nitric Oxide during Doxorubicin‐Induced Cardiomyopathy
Authors: Sayed‐Ahmed Mohamed M. , Khattab Mahmoud M. , Gad Mohamed Z. , Osman Abdel‐Moneim M.
Published: August 2010

Abstract: The major limiting factor in long‐term administration of doxorubicin is the development of cumulative dose‐dependent cardiomyopathy and congestive heart failure. Although several mechanisms have been suggested to explain the exact cause of doxorubicin‐induced cardiomyopathy, the role of the vascular endothelium‐derived vasoactive mediators in the pathophysiology of this toxic effect is still unknown. Accordingly, the present study has been initiated to investigate whether the changes in plasma level of endothelin‐1 and nitric oxide along with cardiac nitric oxide are associated with the development of doxorubicin‐induced cardiomyopathy. Doxorubicin was injected with a single dose of 5 mg/kg and every other day with a dose of 5 mg/kg, intraperitoneally, to have four cumulative doses of, 10, 15, 20 and 25 mg/kg in five separate groups of male rats. An additional group receiving a single dose of 20 mg/kg and one receiving normal saline were also included in the study. Twenty‐four hr after the last dose, the animals were sacrificed and the plasma levels of endothelin‐1 and nitric oxide in addition to cardiac nitric oxide were determined. The results show that doxorubicin caused a statistically significant increase of 85%, 76% and 97% in plasma endothelin‐1 at a cumulative dose levels of 10, 15 and 20 mg/kg, respectively. However, the level of plasma nitric oxide remained unchanged. Furthermore, doxorubicin treatment resulted in a significant dose‐dependent increase in serum lactate dehydrogenase and creatine phosphokinase. In contrast, the increase in nitric oxide production in cardiac tissue by doxorubicin was not dose‐dependent with the maximum increase (81%) at a cumulative dose of 10 mg/kg. It is worth mentioning that plasma endothelin‐1 and cardiac nitric oxide were significantly increased at 24 hr after the single dose of 20 mg/kg doxorubicin. The increase of plasma endothelin‐1 and cardiac nitric oxide with the cardiomyopathy enzymatic indices, may point to the conclusion that both endothelin‐1 and cardiac nitric oxide are increased during the development of doxorubicin‐induced cardiomyopathy.
Rapid Functional Definition of Extended Spectrumβ‐Lactamase Activity in Bacterial CulturesviaCompetitive Inhibition of Fluorescent Substrate Cleavage
Authors: Sallum Ulysses W. , Zheng Xiang , Verma Sarika , Hasan Tayyaba
Published: August 2010

The functional definition of extended‐spectrumβ‐lactamase (ESBL) activity is a clinical challenge. Here we report a rapid and convenient assay ofβ‐lactamase activity through the competitive inhibition of fluorescent substrate hydrolysis that provides a read‐out nearly 40× more rapidly than conventional techniques for functional definition. A panel ofβ‐lactam antibiotics was used for competition againstβ‐lactamase enzyme‐activated photosensitizer (β‐LEAP) yielding a competitive index (Ci) in 30 min. Significant differences in the relativeCivalues of the panel ofβ‐lactams were determinedin vitroforBacillus cereuspenicillinase. Additionally, the relativeCivalues for whole bacterial cell suspensions ofB. cereus5/βwere compared with the relative minimal inhibitory concentration (MIC) values and a correlation coefficient of 0.899 was determined. We further demonstrated the ability ofβ‐LEAP to probe the capacity of ceftazidime to inhibit the enzyme activity of a panel of ESBL‐producingEscherichia coli. The bacteria were assayed for susceptibility to ceftazidime and the relative MIC values were compared with the relativeCivalues for ceftazidime yielding a correlation coefficient of 0.984. This work demonstrates for the first time the whole cell assay of the competitive inhibition ofβ‐lactamase enzyme activity and derivation of associated constants.
Perfectionism and Thoughts About Having Cosmetic Surgery Performed1
Authors: Sherry Simon B. , Hewitt Paul L. , Lee‐Baggley Dayna L. , Flett Gordon L. , Besser Avi
Published: August 2010

Trait perfectionism, perfectionistic self‐presentation, and thoughts about having cosmetic surgery performed (TAHCSP) were examined. In Study 1, perfectionistic self‐promotion (PSP) and nondisplay of imperfection (NDP) correlated with TAHCSP in 292 university women. Both Study 2 (N ‐ 527 university women and 209 university men) and Study 3 (N= 43 gym‐going women and 52 gym‐going men) replicated findings from Study 1. Studies 2 and 3 extended Study 1 by showing that (a) socially prescribed perfectionism (SPP) correlated with TAHCSP and (b) PSP, NDP, and SPP correlated with TAHCSP in women only. PSP and NDP mediated the relation between SPP and TAHCSP in studies 2 and 3. Results held after controlling for age and body mass index. Perfectionists' pursuit of appearance ideals, fault‐finding predilection, and concern over others' evaluations may generate and maintain TAHCSP.
Who Are We Without the I, or the O, or the P?
Authors: Knapp Deirdre J.
Published: August 2010

The first thing that struck me about the Ryan and Ford (2010) article was the irony of the title. Their choice to use the term “organizational” psychology instead of “industrial-organizational” (I-O) psychology was treated rather blithely in a footnote, but I am willing to bet that many readers were taken aback by the word choice. Although I am personally comfortable with calling myself an organizational psychologist, the most recent proposal to change the Society for Industrial and Organizational Psychology (SIOP) to the Society for Organizational Psychology was defeated. At least some of those who voted against the change viewed it as an ominous move to change our identity as a profession. I do not believe it was, but I do think the word choice in the context of this focal article is more substantive to the topic than the authors intended.
A Sense of Identity Does Matter in Achieving Relevance and Meaning in Our Work
Authors: Wright Thomas A.
Published: August 2010

There was a phrase among the Boston immigrant Irish in the latter part of the 19th century that went something like this, “I shook the hand that shook the hand that shook the hand … of the Great John L ….” This saying was in reference to the strong sense of identity that the Boston Irish shared with one of the first of their very own to gain international recognition and fame: the heavyweight champion of the world (1882–1892), John L. Sullivan. Undoubtedly the first national sports hero and best-known American of his generation, John L. Sullivan represented the hopes and aspirations of the millions of Americans who identified with him (Isenberg, 1988). His widely heralded success story is credited for acting as a “tipping point” for many youth to forsake a life of crime.
Let's Focus on Two-Stage Alignment Not Just on Overall Performance
Authors: Bartram Dave , Warr Peter , Brown Anna
Published: August 2010

Johnson et al. (2010) note the need for a vector defining the relationships between job components and overall job performance (OJP) in the job requirements matrix approach to synthetic validation. This need is also implicit in the job components validity approach that they discuss. In our view, relationships between job components and overall criteria such as OJP are central to synthetic validation, as the effectiveness of this approach depends on the generalizability of relationships between job and criterion components across jobs, organizations, and (of increasing importance) countries.
Better at What?
Authors: Russell Craig J.
Published: August 2010

In reading the title of Johnson et al.'s (2010) article on synthetic validity, I immediately asked myself “Better at what?” Motor oil serves three functions in internal combustion engines: lubricate, cool, and clean engine parts. There is little doubt that synthetic motor oil does all three of these better than nonsynthetic motor oil, although some might argue that it is not as cost effective. Johnson et al. described two approaches to synthetic validity and then argued why synthetic validity is “the best approach for many situations.” I strongly agree with their contention that synthetic validity is “practically useful” and with their less directly stated contention that it also holds value in developing theory. Hence, I will limit my comments exactly to how synthetic validity inferences might best contribute to the complimentary goals of advancing theory and practice, although these might cause Johnson et al. to rethink some of their observations.
Can Synthetic Validity Methods Achieve Discriminant Validity?
Authors: Schmidt Frank L. , Oh In-Sue
Published: August 2010

Our focus is on the difficulties that synthetic validity encounters in attempting to achieve discriminant validity and the implications of these difficulties. Johnson et al. (2010) acknowledge the potential problems involved in attaining discriminant validity in synthetic validity. For example, they report that Peterson et al. (2001), Johnson (2007), and other synthetic validity studies report failure to achieve discriminant validity. What this failure means is that a synthetic validity equation developed to predict validity for Job A does as well in predicting validity for Jobs B, C, D, and so forth as it does for Job A. Johnson et al. then go on to propose that this problem might be overcome by careful attention to both the criterion and predictor sides of synthetic validity. We question whether their proposals can be made to work.
Synthetic Oil Is Better for Whom?
Authors: Hollweg Lewis
Published: August 2010

After reviewing the article by Johnson et al. (2010), I began to ask myself and other industrial and organizational (I-O) psychologists what interest groups might be impacted by a Society for Industrial and Organizational Psychology (SIOP)-sponsored synthetic validity database and its resulting mechanical behavior and performance predictions. Who are the various stakeholders and what might be the positive or negative outcomes caused by this “disruptive technology” that could cause “creative destruction” in the I-O psychology profession? Among the consumers and producers of performance prediction, who might gain and who might be creatively destroyed? From these questions and the subsequent conversations, I identified the following categories and possibilities, but I am sure there are others that I have not anticipated.
SOME KEY ISSUES AND ACCESSES TO THE APPLICATION OF MAGNESIUM ALLOYS
Authors: HAO YUAN , CHEN TIJUN , MA YING , LI YUANDONG , YAN FENGYUN , HUANG XIAOFENG
Published: August 2010

The status of Mg alloy application, and then some key issues limiting their applications and the corresponding accesses were briefly discussed. It was supposed that development of new alloys with high performance and low cost, investigating advanced forming technology, and development of credible and effective surface modification technologies and related equipment were the urgent tasks in present. Correspondingly, three aspects of researches were carried out. (1) A new alloy with high strength and elongation, but low RE and Zn contents, named ZW21, was invented. (2) Semisolid ingots of AZ91D, AM60 and ZW21 alloys available for thixoforming were prepared. Thixoforming increased the ultimate tensile strength of AZ91D alloy by 20% compared with permanent mould casting. (3) A new kind of micro arc oxidation equipment with a capacity of treating 6m2 surface was developed and has been used to treating motorcycle hub of magnesium alloy.
THE FAILURE BEHAVIOR OF EXTRUDED Mg-12Gd-3Y-0.4Zr ALLOY SUBJECTED TO IMPACT LOADING
Authors: JI WEI , FAN YAFU
Published: August 2010

Dynamic failure behaviors of the extruded Mg -12 Gd -3 Y -0.4 Zr alloy were investigated by means of optical microscope and scanning electron microscope (SEM). The dynamic tensile and compressive tests were carried out at 423K~798K and strain rates of 102~103s-1 using a split Hopkinson pressure bar. Additionally, in order to study the failure characteristic of this alloy at higher strain rates, such as 107s-1, a series of ballistic tests were carried out. The results indicate that the failure mechanisms of both tensile and compressive specimens exhibit an obvious dependence on the temperature. As the testing temperatures increased from 423K to 798K, the fractographs of the tensile specimens varied from quasi-cleavage fracture to intergranular rupture, and the failure modes of the compressive specimens changed from shear cracks to dynamic recrystallization zone. Adiabatic shear bands with an average width 10µm were observed in the post-test magnesium targets penetrated by steel balls.
FORMATION OF La-Al-Ni-Cu-Fe BULK METALLIC GLASSES WITH HIGH GLASS-FORMING ABILITY
Authors: JI YUNFEI , PANG SHUJIE , MA CHAOLI , ZHANG TAO
Published: August 2010

The effect of alloy composition on improving glass-forming ability of La -based alloys is investigated in this work. Previous composition criteria demonstrated that the alloys with high glass-forming ability should have negative heats of mixing among the main constituent elements. In this study, the addition of Fe to a La -based La - Al - Ni - Cu alloy significantly improved the glass-forming ability, although the heat of mixing between Fe and the main element La is positive. La - Al - Ni - Cu - Fe bulk metallic glasses with diameters up to 15 mm were prepared by the method of pouring the molten alloys into a copper mold. These La - Al - Ni - Cu - Fe bulk metallic glasses exhibit relatively wide supercooled liquid region of about 50 k, and high T rg (T g /T l ) and γ(T x /(T g +T l )) values. It is found that the addition of Fe to the La - Al - Ni - Cu alloy lowers the Gibbs free energy difference between the liquid and crystalline phases in the supercooled liquid region and enhances the glass-forming ability of the alloy.
QUANTIFYING THE PERFORMANCE OF MULTIPLE-OUTPUT PIEZOELECTRIC OPTICAL SWITCHES
Authors: LENG M. , HAEMMERLE E. , CHEN W. , HODGSON M. , GAO W.
Published: August 2010

Optical switch prototypes are developed based on the new concept that the input fiber is directly moved by the deflection of a piezoelectric tube actuator. The piezoelectric tube actuators used in the switch prototypes are manufactured by an electrophoretic deposition process. The tubes are low cost and compact in size with an inner diameter of less than 1mm. They have a deflection of 65 µm which is adequate to actuate the input fiber for switching.

A number of multimode 1×2 fiber optical switch prototypes have previously been built. To develop the new 1×4 optical switch, a new output fiber alignment device was fabricated. The conductive coating on the piezoelectric tube actuator was sectored into four. Also, the power supply unit was redesigned in order to provide high voltage for the four-sectored tube. The success in the 1×4 prototype development proves that the new multiple-output piezoelectric switching concept is feasible. The concept demonstrates an advantage over some other opto-mechanical switches which need to be cascaded to achieve a multiple-output configuration.
RECENT PROGRESSES IN POLYMERIC SMART MATERIALS
Authors: LIU YAN-JU , LAN XIN , LU HAI-BAO , LENG JIN-SONG
Published: August 2010

Smart materials can be defined as materials that sense and react to environmental conditions or stimuli. In recent years, a wide range of novel smart materials have been developed in biomaterials, sensors, actuators, etc. Their applications cover aerospace, automobile, telecommunications, etc. This paper presents some recent progresses in polymeric smart materials. Special emphasis is laid upon electroactive polymer (EAP), shape memory polymer (SMP) and their composites. For the electroactive polymer, an analysis of stability of dielectric elastomer using strain energy function is derived, and one type of electroactive polymer actuator is presented. For the shape memory polymer, a new method is developed to use infrared laser to actuate the SMP through the optical fiber embedded within the SMP. Electrically conductive nanocarbon powders are utilized as the fillers to improve the electrical conductivity of polymer. A series of fundamental investigations of electroactive SMP are performed and the shape recovery is demonstrated.
THERMOMECHANICAL PROPERTY OF EPOXY SHAPE MEMORY POLYMERS
Authors: WU XUELIAN , ZHENG HUI , LIU YANJU , LENG JINSONG
Published: August 2010

Epoxy shape memory polymers (SMPs) were preparation and their mechanical properties are focused on. Full shape recovery is observed at 150 °C for each polymer, and the SMP with lower hardener content shows a quicker shape recovery speed. In addition to a good thermal stability, glass transition temperature of the polymers increases with increasing hardener content. Of particular attention of DMA test is that the epoxy SMPs show a high storage modulus not only in glass state but also in rubber state. The tension test indicates that both stress at break and corresponding elastic modulus vary with a peak value for the polymers.
STUDY OF COMPOSITE PLATE DAMAGES USING EMBEDDED PZT SENSORS WITH VARIOUS CENTER FREQUENCY
Authors: KANG KYOUNG-TAK , CHUN HEOUNG-JAE , SON JU-HYUN , BYUN JOON-HYUNG , UM MOON-KWANG , LEE SANG-KWAN
Published: August 2010

This study presents part of an experimental and analytical survey of candidate methods for damage detection of composite structural. Embedded piezoceramic (PZT) sensors were excited with the high power ultrasonic wave generator generating a propagation of stress wave along the composite plate. The same embedded piezoceramic (PZT) sensors are used as receivers for acquiring stress signals. The effects of center frequency of embedded sensor were evaluated for the damage identification capability with known localized defects. The study was carried out to assess damage in composite plate by fusing information from multiple sensing paths of the embedded network. It was based on the Hilbert transform, signal correlation and probabilistic searching. The obtained results show that satisfactory detection of defects could be achieved by proposed method.
SIZE EFFECT ON DEFORMATION MODE IN MICRON-SIZED Ti-5Al SINGLE CRYSTAL LOADED ALONG $[2\,\overline 1 \,\overline 1 \,0]$ AND [0001]
Authors: XIAO LIN , YU QIAN , SUN QIAOYAN , SUN JUN
Published: August 2010

Free-standing sub-micron Ti -5 Al single crystal square pillars were fabricated along [Formula: see text] double slip and [0001] twinning orientations using FIB fabrication processes. Samples in range of 0.4 to 2.0µm were compressed. The yield stress increases much higher than their bulk counterpart as the specimen width decreases. The tendency of "smaller is stronger" is displayed in Ti -5 Al single crystals loaded along [Formula: see text] and [0001] orientations. The number of slip systems is restricted by specimen physical size as it declines from 2µm to 0.5µm, when the specimens were subjected to double slip loading. Meanwhile, when sample size is less than 1.0µm, micro-pillars along twinning orientation have to compensate the incomplete twinning deformation via shearing due to geometrical restriction and dislocation starvation effects. This variation of deformation mode could be attributed to the starvation effect of dislocations.
CYCLIC DAMAGE IN STEEL EXPERIENCING SEISMIC LOADING
Authors: SEAL C. K. , HODGSON M. A. , FERGUSON W. G.
Published: August 2010

During the mid 1990s earthquakes in Northridge, California, and Kobe, Japan, illustrated a lack of understanding of the behaviour of structural steels exposed to seismic loads. Under this type of load regime, structural steel members are subjected to fully plastic load cycles and unexpectedly brittle failures may result.

A method for determining the accumulation of damage through cyclic pre-straining is proposed. Toughness, as defined by the area under the true stress strain curve, is used as an indicator of the level of damage that the steel has suffered and from this some idea of its remaining capacity to further deform can be determined.

Observations during the testing of these samples have indicated that there is a transition in the failure mode from a fatigue type failure, with a progressively growing crack, to an overload failure, in which the steel fails due to a lack of ability to further deform. Similar transitions have been noted by other researchers in the field. Analysis of the test results seems to show differences in the damage accumulation behaviour that may be used to identify when this transition in failure modes may occur.
DESIGN OF A 5-AXIS MACHINE TOOL CONSIDERING GEOMETRIC ERRORS
Authors: PARK SUNG-RYUNG , YANG SEUNG-HAN
Published: August 2010

Control over scale, dynamic, environment, and geometric errors in 5-axis machine tool are required to realize a high precision machine tool. Especially geometric errors such as translational, rotational, offset, and squareness errors are important factors which should be considered in the design stages of the machine tool. In this paper, geometric errors are evaluated for different configurations of 5-axis machine tool, namely, 1) table tilting, 2) head tilting, and 3) universal and their error synthesis models are derived. The proposed model is different from the conventional error synthesis model since it considers offset and offset errors. The volumetric error is estimated for every configuration with random geometric errors. Finally, the best configuration, the critical design parameter and error are suggested.
FATIGUE PROPERTIES OF TI-6AL-4V SUBJECTED TO 0.9% PHYSIOLOGICAL SALINE SOLUTION
Authors: CAO XIAOJIAN , MURAKAMI RI-ICHI , WANG QINGYUAN
Published: August 2010

Fatigue properties of Ti -6 Al -4 V (TC4) subjected to 0.9% physiological saline solutions were presented in this paper. The ultrasonic fatigue test method has been used to investigate the very high cycle fatigue properties of commercial titanium alloy TC4 with the microstructure of tramsformed lamellar dipped into 0.9% physiological saline solution prior to testing. Three estimated times have been decided for subjecting at 37 °C, such as 24 hours, 2 weeks and 4 weeks. The results show that physiological saline solution treatment makes a little influence on the ultrasonic fatigue life of TC4. The slope of S-N curve decreases as the dipping time increases. Dipping tests for three estimated times also have been performed. When TC4 has been dipped into physiological saline solution for 4 weeks, homogeneous white points have been observed on specular facet specimen. And in the fracture surface of which has been dipped for 4 weeks, new inclusion sized 5-10 µm in the crack initiation has been observed. The fractography pictures show the fracture to be transcrystalline plastic. Cracks are initiated because of the subsurface inclusion and the facet slip of α-phase.
RESIDUAL STRESS DEVELOPMENT IN CU THIN FILMS WITH AND WITHOUT AlN PASSIVATION BY CYCLIC PLANE BENDING
Authors: SHINOHARA MITSUHIKO , HANABUSA TAKAO , KUSAKA KAZUYA
Published: August 2010

Since the thin film technology is applied to micro-machines, MEMS (micro electro-mechanical system), optical devices and others, the evaluation of mechanical properties in thin films becomes to be important. On the other hand, there are differences in mechanical properties between bulk materials and thin films, but studies in this field have not yet been made enough. The present paper reports on the evaluation of the mechanical properties of Cu thin films with and without AlN passivation layer. Specimens with different thickness of Cu film were subjected to cyclic plane bending fatigue test. Residual stresses developed in the Cu films were measured in a sequence of bending cycles using X-ray diffraction method in order to understand the effect of film thickness and passivation layer on mechanical properties of Cu thin films.
ENHANCED TENSILE DUCTILITY IN AN ELECTRODEPOSITED CU WITH NANO-SIZED GROWTH TWINS
Authors: WANG GUOYONG , JIANG ZHONGHAO , LIAN JIANSHE
Published: August 2010

A fully dense electrodeposited microcrystalline copper with nano-scale twins was synthesized by electrodeposition. The microstructure of this copper was analyzed X-ray diffractometer (XRD) and by transmission electron microscopy (TEM). The grains of mean size about 2mm were divided by high density of growth twins with mean lamellar thickness of about 90 nm. Tensile tests at different strain rates and room temperature showed that the strength increased from 379 MPa to 458 MPa with strain rate increasing from 10-5 s-1 to 0.1 s-1. The elongations to fracture were in the range of 13.6~15.5%. So this Cu has good combination of strength and ductility. The strengths are much higher than that determined by Hall-Petch relation with the same grain size, which means that twin boundaries are effective in blocking dislocation motion. The strain rate sensitivity and activation volume estimated from the flow stress versus strain curves was 0.016 and 84 b3~69b3, respectively. Such a large activation volume indicates that the deformation of this copper was controlled by dislocation process.
A STUDY ON MECHANICAL PROPERTIES OF PVA FIBER REINFORCED SUPER-LIGHTWEIGHT MORTAR
Authors: DATE SHIGEYUKI , KASAI TETSURO
Published: August 2010

In this study, not only bending strength of Super-lightweight mortar (SLM) but also resistance to impact load of it, with several types of PVA fibers of different lengths and diameters, were investigated. It was shown that, when the diameter of the fiber decreased and fiber-volume fraction increased, bending strength and resistance to the impact load were generally improved. However, the effect of the performance improvement of the SLM showed the tendency to become small in mix proportion that has too large total surface area of fiber.
CHARACTERIZATION OF STAINLESS STEEL FIBER REINFORCED ALUMINUM COMPOSITE USING ULTRASONIC NONLINEARITY
Authors: KIM CHUNG SEOK , JHANG KYOUNG YOUNG , HYUN CHANG YOUNG
Published: August 2010

A 304 stainless steel short fiber reinforced aluminum composite was fabricated and investigated for matrix voids as well as interfacial reaction using ultrasound. The aluminum composite was made by a hot isostatic pressing technique at a temperature of 600°C and subsequent aging at 120°C. The tensile strength significantly increased with the addition of 5% stainless steel fiber. The interfacial reaction evolved and grew with aging time due to generation of intermetallic FeAl 2. The ultrasonic nonlinearity (β/β0) increased with the volume fraction of fiber and aging heat treatment because of the generation of microvoids resulted from localized fibers and matrix precipitation. This study demonstrates the potential for characterization of reinforced composite materials fabricated by the powder metallurgy technique.
EXPERIMENTAL STUDY ON BASIC PERFORMANCE OF ELECTROOSMOTIC PUMP WITH ION EXCHANGING POROUS GLASS SLIT
Authors: LEE HO , KIM GYU MAN , LEE CHOON YOUNG , PARK CHEOL WOO , KIM DAE JOONG
Published: August 2010

The basic concept and preliminary performance results of a miniaturized electroosmotic pump with diaphragms were included in the present study. The separation of an electroosmotic pumping liquid from a drug using diaphragms is mainly to have a freedom in choosing an electroosmotic pumping liquid and to achieve the optimal drug delivery with its preferable precise control. As a result, the maximum flow rate and current increased linearly according to the increment of applied voltage that is electric potential.
EXPERIMENTAL STUDIES ON DYNAMIC MECHANICAL BEHAVIORS AND ANTI-PROJECTILE CAPABILITIES OF EXTRUDED MAGNESIUM ALLOY
Authors: FAN YAFU , ZHAO BAORONG
Published: August 2010

Dynamic mechanical behaviors of Mg - Gd - Y series extruded magnesium alloy and its σ-εcurves are measured by using of Hopkinson pressure bar technique. According to the concept of efficiency of absorption energy, this thesis compares Mg - Gd - Y series extruded alloy with ZK60 extruded magnesium alloy. Being obtained similitude numbers by means of normalizing processing for governing equations of the continuum mechanics and according to the viewpoint of equal density of area, the comparative experiment of anti-projectile capabilities is elaborately designed between Mg - Gd - Y alloy and the 7A52 aluminum alloy. The result has validated that anti-projectile capability of Mg - Gd - Y alloy is better than those of 7A52 alloy under the condition of equal density of area. The relative technique approaches for improving anti-projectile capability of Mg - Gd - Y alloy are put forward making use of similitude numbers. Finally, the basic characters of effect of adiabatic shear are revealed by micro analysis.
FABRICATION OF MICRO PROBE-TYPE ELECTRODES FOR MICROELECTRO-CHEMICAL MACHINING USING MICROFABRICATION
Authors: PARK W. B. , CHOI J. H. , PARK C. W. , KIM G. M. , SHIN H. S. , CHU C. N. , KIM B. H.
Published: August 2010

In this study, the mass fabrication of microelectrode tools for microelectrochemical machining (MECM) was studied using microfabrication processes. The cantilever type geometry of microelectrodes was defined by photolithography processes, and metal patterns were made for electrical contacts. Various fabrication processes were studied for the fabrication of microelectrode tools, such as wet etching, lift-off, and electroforming for metal layer patterning. MECM test results showed feasibility of the fabricated electrode tools. The microfabricated electrodes can be used as micromachining tools for various electrical micromachining of steel mold and parts of microdevices.
FATIGUE CHARACTERISTICS OF SKD-61 BY ULTRASONIC NANOCRYSTAL SURFACE MODIFICATION TECHNOLOGY UNDER STATIC LOAD VARIATION
Authors: SUH CHANG-MIN , LEE MOON-HWAN , PYOUN YOUNG-SIK
Published: August 2010

At first, the specimens of SKD-61 are prepared and tested to verify the effects of ultrasonic nano-crystal surface modification (UNSM) technology on the variation of mechanical properties under static load variation. 20 kHz frequency was applied to the ball tip, and the applied static forces were changed three kinds of load level 40, 60, and 80 N, respectively. The grain size of SKD-61 surface treated by UNSM becomes very fine to nano-scale crystal and structure is observed till certain depth. The compressive residual stress becomes -810, -1200 and -1400 MPa to a 150 µm depth after the UNSM process according to three kinds of load level 40, 60, and 80 N, respectively. Fatigue limits of 107 cycles are increased by 8.3, 11.2, and 17.9% after UNSM at the smooth specimen according to three kinds of load level, respectively. Interior-originating fracture, fish-eye crack, occurs after UNSM because of a nano structured modification by a surface plastic deformation and compressive residual stress in the case of the smooth specimen. UNSM improves the mechanical properties effectively and is becoming a practical method to improve the service life of the trimming knives. Productivity and reliability of a cold rolling process have improved more than 2 times by the application of the UNSM trimming knives.
TEMPERATURE EFFECT OF LOW VELOCITY IMPACT RESISTANCE OF GLASS/EPOXY LAMINATES
Authors: KANG KI-WEON , KIM HEUNG-SEOB , CHUNG TAE-JIN , KOH SEUNG-KEE
Published: August 2010

This paper aims to evaluate the effect of temperature on impact damage resistance of glass/epoxy laminates. A series of impact tests were performed using an instrumented impact-testing machine at temperature ranging from -40°C to +80°C. The resulting impact damage was measured using back light method. The impact resistance parameters were employed to understand the damage resistance. It was observed that temperature has a little effect on the impact responses of composite laminates. The damage resistance of glass/epoxy laminates is somewhat deteriorated at two opposite extremes of the studied temperature range and this behavior is likely due to the property change of glass/epoxy laminates under extreme temperatures
THE EFFECT OF CYCLIC HYGROTHERMAL ENVIRONMENT ON INTERLAMINAR SHEAR STRENGTH (ILSS) OF CCF300/BMI COMPOSITE
Authors: ZHAO YAN , LUO YUN-FENG , DUAN YUE-XIN , DU SHAN-YI
Published: August 2010

An experimental study was conducted to examine the effect of cyclic hygrothermal environment on the interfacial property of CCF300/BMI composites. The moisture weight and interlaminar shear strength of CCF300/BMI composites specimen of each stage during three absorption-desorption cyclical stages was investigated. The results showed the ILSS of composites after water absorption dramatically decreased, but it could make a comeback on the whole after removal of water.
A DESIGN OF THE DRIVER AIRBAG MODULE WITH FLOATING HORN ASSEMBLY
Authors: SUH CHANG-MIN , LEE YOUNG-HOON , SUH DUCK-YOUNG
Published: August 2010

The driver airbag system is designed as a supplemental restraint system in addition to the seatbelt, and is designed to protect the driver's head and chest against severe injury by a device that is actuated in case of vehicle's fronted impact. Deployment of an airbag module with floating horn assembly is a highly dynamic process. The concept of driver airbag module with floating horn assembly and aluminum emblem is presented as a useful parameter when the airbag deploys and the energy is evaluated as performance factor in airbag module. Floating horn assembly is also one of the major factors for driver airbag module design to perform its horn function and check the package between driver airbag module and steering wheel.

This study on the design of driver airbag module with floating horn assembly proved the feasibility as a new safety device. However, the system level study is needed for decrease of passenger injury. This study can be used for the implementation of a prototype of DABM with floating horn device.
SITE PREFERENCE AND ELASTIC PROPERTIES OF A2-Ti3Al WITH OXYGEN IMPURITY: A FIRST-PRINCIPLES STUDY
Authors: WEI YE , ZHANG YING , LU GUANG-HONG , XU HUIBIN
Published: August 2010

We employed a first-principles method based on the density functional theory to investigate the effect of impurity O on the site preference and elastic properties of α2- Ti 3 Al . We found that the O atom prefers to occupy the Ti -rich octahedral interstitial site in α2- Ti 3 Al . We calculated the elastic constants of α2- Ti 3 Al with single O atom, which demonstrate that the O presence has no large effect on α2- Ti 3 Al according to the empirical criterions. Other factors such as O cluster should be taken into account to understand the deleterious effect of O on α2- Ti 3 Al . Our results provide a useful reference to further study the mechanical properties of TiAl alloys.
EXPERIMENTAL ANALYSIS ON FLOW AROUND A CIRCULAR AND AN ELLIPTIC HOOP-TYPED RING BY USING A PIV TECHNIQUE
Authors: PARK CHEOL WOO , KIM GYU MAN , LEE CHOON YOUNG , LEE HO , KIM HYUNG BUM
Published: August 2010

In the present study, we measured velocity vector fields around hoop rings at each divided sections by using a particle image velocimetry method. The ring model used in this study was made of brass with two different aspect ratios and the experiment is carried out in a circulating water channel. As a result, we can observe two counter-rotating vortical flow structures around each hoop regime that is attributed to the interaction between direct pass through flow of hoop center and the shear flow separated from sharp-edged end of ring hoop.
CUTTING FORCES ANALYSIS IN WHIRLING PROCESS
Authors: SON JAE HWAN , HAN CHANG WOO , KIM SUN IL , JUNG HEE CHUL , LEE YOUNG MOON
Published: August 2010

Whirling is a cutting process in which a series of cutting edges remove material by turning over the rotating workpiece. In this process, the whirling ring with a number of cutting teeth combined with the rotation and advancement of workpiece, produces pitches of worm. Mechanics of chip formation of the process, however, has not been fully estabilished. To estimate the cutting force during the process, the kinematics and the maximum undeformed chip thickness to be removed by each cutting edge should be thoroughly analyzed.

In this study, using the recently developed model of undeformed chip thickness and the DEFORM software, cutting forces of the whirling process are estimated. The effects of cutting forces on tool are analyzed using the ADAMS software. The validity of the simulations has been verified with a series of cutting experiments.
ANALYSIS OF RESIDUAL STRESS FOR NARROW GAP WELDING USING FINITE ELEMENT METHOD
Authors: LEE CHOON YEOL , HWANG JAE KEUN , BAE JOON WOO
Published: August 2010

Reactor coolant loop (RCL) pipes circulating the heat generated in a nuclear power plant consist of so large diameter pipes that the installation of these pipes is one of the major construction processes. Conventionally, a shield metal arc welding (SMAW) process has been mainly used in RCL piping installations, which sometimes caused severe deformations, dislocation of main equipments and various other complications due to excessive heat input in welding processes. Hence, automation of the work of welding is required and narrow-gap welding (NGW) process is being reviewed for new nuclear power plants as an alternative method of welding. In this study, transient heat transfer and thermo-elastic-plastic analyses have been performed for the residual stress distribution on the narrow gap weldment of RCL by finite element method under various conditions including surface heat flux and temperature dependent thermo-physical properties.
THE RELATION BETWEEN ROTATION DEFORMITY AND NERVE ROOT STRESS IN LUMBAR SCOLIOSIS
Authors: KIM HO-JOONG , LEE HWAN-MO , MOON SEONG-HWAN , CHUN HEOUNG-JAE , KANG KYOUNG-TAK
Published: August 2010

Even though several finite element models of lumbar spine were introduced, there has been no model including the neural structure. Therefore, the authors made the novel lumbar spine finite element model including neural structure. Using this model, we investigated the relation between the deformity pattern and nerve root stress. Two lumbar models with different types of curve pattern (lateral bending and lateral bending with rotation curve) were made. In the model of lateral bending curves without rotation, the principal compressive nerve root stress on the concave side was greater than the principal tensile stress on the convex side at the apex vertebra. Contrarily, in the lateral bending curve with rotational deformity, the nerve stress on the convex side was higher than that on the concave side. Therefore, this study elicit that deformity pattern could have significantly influence on the nerve root stress in the lumbar spine.
COMPARISON OF TRANSVERSE FLUX LINEAR MOTOR AND LONGITUDINAL FLUX LINEAR MOTOR FOR COOLER OF INFORMATION AND TELECOMMUNICATION
Authors: WOO BYUNG-CHUL , HONG DO-KWAN
Published: August 2010

This paper is associated with the manufacture of 60W Transverse Flux Linear Motor (TFLM), and the thrust force and the maximum displacement of TFLM is compared with Longitudinal Flux Linear Motor (LFLM). Thus, the force which follows in location of the electric motor is simulated with ANSYS, and the thrust force of the linear actuator with applied current is tested. And the experiment results by several cases of alternating current is reported.
FLEXURAL PROPERTIES OF INJECTION-MOLDED BAMBOO/PBS COMPOSITES
Authors: OHKITA KAZUYA , TAKAGI HITOSHI
Published: August 2010

In recent years, from an environmental perspective, there has been increasing interest in the change to a sustainable society. The use of natural-fiber-reinforced biodegradable composites has been proposed as one solution. Bamboo is an often used renewable bio-resource; it has an inherent advantage of rapid growth. Polybutylene succinate ( PBS ), used as matrix resin, has biodegradable characteristics. This paper describes flexural properties of bamboo/ PBS composites prepared by injection molding. The following results were obtained. The flexural modulus was improved with increasing bamboo powder contents when the cylinder temperature of the injection molder was 140°C. However, the flexural strength showed the opposite tendency to be decreased with increasing bamboo powder contents. An SEM photomicrograph of the fracture surface for bamboo/ PBS composites showed typical fracture behavior of pull-out fibers without fiber fracture. Furthermore, there was no adhesion of PBS resin on the bamboo fiber surface. Processing conditions affected mechanical properties of bamboo/ PBS composites, imparting higher flexural strength and flexural modulus at high cylinder temperatures such as 180°C and 200°C.
CRACK-HEALING BEHAVIOR AND BENDING STRENGTH PROPERTIES OF SiC CERAMICS BASED ON THE TYPE OF ADDITIVE SiO2 EMPLOYED
Authors: NAM KI WOO , KIM JONG SOON , PARK SEUNG WON
Published: August 2010

Silicon carbide ( SiC ) exhibits good strength at high temperatures and resistance to radioactivity. However, it has poor fracture toughness. The ability to heal cracks represents a very desirable means of overcoming this weakness. This study focuses on the crack-healing behavior and bending strength of SiC ceramics to which sintering additives have been added. Optimized crack-healing condition was found to be 1hr at an atmospheric level of 1100 °C. The maximum crack size that can be healed at the optimized condition was a semi-elliptical surface crack of 450 µm in diameter. Si oxide was revealed to be the principle material involved in crack-healing.
PHASE TRANSFORMATION IN SiO2-Si3N4 SYSTEM WITH Li2CO3 ADDITIVE
Authors: ZHANG FANFEI , ZHANG YUE , LI ANG , ZHANG DAHAI , LI ZONGPING
Published: August 2010

In the present work, a series of samples were prepared by pressureless sintering from the starting materials of Si 3 N 4 (α and/or β phases), SiO 2 and Li 2 CO 3. The phase transformation was studied with emphasis on the influence of sintering temperature and Li 2 CO 3 content. Related phase transformation was observed and analyzed by SEM and XRD and probable mechanisms were given, which will be helpful for the further explanation to the oxidation mechanism of Si 3 N 4 based ceramics at elevated temperature.
IMPROVEMENT OF AMBIENT DUCTILITY AND TOUGHNESS BY Γ PHASE PRECIPITATION IN NIAL-CR(MO)/NB ALLOYS
Authors: TANG LINZHI , LI SHUSUO , GONG SHENGKAI
Published: August 2010

Effects of different ratios of Ni to Al on the ductility and toughness of Ni 33+ x Al 28- x Cr 30 Mo 4 Nb 5 ( x =0, 6, 9, 12) alloys are investigated. High temperature compression test is also conducted. The results show that with ratio of Ni to Al up to 1.77, γ phase precipitation result in ductility and fracture toughness enhanced at room temperature. The reinforced Cr 2 Nb -type phase and γ phase benefit for the high temperature strength and room temperature ductility, respectively.
EFFECT OF POROSITY ON PARTICLE EROSION WEAR BEHAVIOR OF LAB. SCALE SICF/SIC COMPOSITES
Authors: SUH MIN-SOO , KOHYAMA AKIRA
Published: August 2010

The use of silicon-based ceramics and composites as combustor liners and turbine vanes provides the potential of improving next-generation turbine engine performance, through lower emissions and higher cycle efficiency, relative to today's use of super alloy hot-section components. As a series of research for FOD resistant, a particle erosion wear test was carried out for continuous Pre- SiC fiber-reinforced SiC matrix composites with a new concept of lab. scale fabrication by LPS process. The result shows that aperture (some form of porosity) between fiber and interface has a deleterious effect on erosion resistance. Aperture along the fiber interfaces consequently causes a severe wear in the form of fiber detachment. Wear rate increase proportional as contents of open porosity increases. For nearly full dense composite materials of about 0.5 % porosity, are about 200 % more wear-resistant than about 5 % porous composites. Grain growth and consolidate condition of matrix which directly affects to FOD resistant are also discussed.
EFFECT OF VACUUM INDUCTION MELTING TECHNOLOGY ON MECHANICAL PROPERTIES OF Nb-16Si-22Ti-2Al-2Hf-17Cr ALLOY
Authors: LI XIAOJIAN , ZHANG HU , SHA JIANGBO
Published: August 2010

This paper dealt with the effect of different induction melting technologies on mechanical properties of Nb -16 Si -22 Ti -2 Al -2 Hf -17 Cr alloy. The cast ingots were fabricated first by arc-melting, and then remolten in the vacuum induction furnace. The results showed that the ingot with refining process of 1800°C/15min and 0.1 at% C addition had finer microstructure and higher room-temperature fracture toughness. In addition, the compressive strength of the ingot with refining technology of 1700°C/10min was 315MPa at 1250°C. However, the arc melting ingot had the lowest fracture toughness and high-temperature compressive strength.