bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationships between core factors of knowledge management in hospital nursing organisations and outcomes of nursing performance
Authors: Lee Eun Ju , Kim Hong Soon , Kim Hye Young
Published: April 2014

Aims and objectives

The study was conducted to investigate the levels of implementation of knowledge management and outcomes of nursing performance, to examine the relationships between core knowledge management factors and nursing performance outcomes and to identify core knowledge management factors affecting these outcomes.

Background

Effective knowledge management is very important to achieve strong organisational performance. The success or failure of knowledge management depends on how effectively an organisation's members share and use their knowledge. Because knowledge management plays a key role in enhancing nursing performance, identifying the core factors and investigating the level of knowledge management in a given hospital are priorities to ensure a high quality of nursing for patients.

Design

The study employed a descriptive research procedure.

Participants

The study sample consisted of 192 nurses registered in three large healthcare organisations in South Korea.

Method

The variables demographic characteristics, implementation of core knowledge management factors and outcomes of nursing performance were examined and analysed in this study.

Results

The relationships between the core knowledge management factors and outcomes of nursing performance as well as the factors affecting the performance outcomes were investigated. A knowledge‐sharing culture and organisational learning were found to be core factors affecting nursing performance.

Conclusion

The study results provide basic data that can be used to formulate effective knowledge management strategies for enhancing nursing performance in hospital nursing organisations. In particular, prioritising the adoption of a knowledge‐sharing culture and organisational learning in knowledge management systems might be one method for organisations to more effectively manage their knowledge resources and thus to enhance the outcomes of nursing performance and achieve greater business competitiveness.

Relevance to clinical practice

The study results can contribute to the development of effective and efficient knowledge management systems and strategies for enhancing knowledge‐sharing culture and organisational learning that can improve both the productivity and competitiveness of healthcare organisations.
Contextual Innovation Management Using a Stage‐Gate Platform: The Case of Philips Shaving and Beauty
Authors: van der Duin Patrick A. , Ortt J. Roland , Aarts Wieger T. M.
Published: April 2014

To improve its innovation process, Philips Shaving and Beauty (S&B) designed a blueprint for its innovation process. Although it has proved to be quite effective, it has experienced a lack of efficiency, in terms of frequent cost and time overruns, in the fuzzy front end of this process. We suggest a contextual innovation management approach to set up a stage‐gate‐based innovation process platform and thus improve the efficiency in the fuzzy front end, which means that, for different contexts, stage‐gate process variants will be designed from which unnecessary activities are removed and important activities are emphasized. The design is based on the identification of relevant contextual factors to develop variations of the common innovation process within Philips S&B. We distinguished different variants of the innovation processes within Philips S&B that can increase the efficiency in the fuzzy front end. Based on interviews within and outside Philips S&B, we identified problems and potential solutions with regard to efficiency in eight recently finished innovation processes. The results indicate that the most important contextual factors are the distinction between incremental and radical innovations, and between market and technology‐based innovations. We used these factors to design three variants on the basic platform of the stage‐gate process.
Intranasal epidermoid cyst causing upper airway obstruction in three brachycephalic dogs
Authors: Murgia D. , Pivetta M. , Bowlt K. , Volmer C. , Holloway A. , Dennis R.
Published: April 2014

This case report describes three brachycephalic dogs with intranasal epidermoid cysts that were causing additional upper airway obstruction. Although epidermoid cysts have been described in several locations in dogs, to the authors’ knowledge intranasal epidermoid cysts have not been previously reported. All dogs had mucopurulent to haemorrhagic nasal discharge. Magnetic resonance imaging of the head revealed the presence of unilateral or bilateral intranasal cystic lesions obstructing the nasal cavities partially or completely, with atrophy of the ipsilateral nasal turbinates. The cystic lesions were surgically excised in all dogs using a modified lateral alveolar mucosal approach to the affected nasal cavity. Aerobic, anaerobic and fungal culture of the cystic contents were negative and histology of the excised tissue was consistent with a benign intranasal epidermoid cyst in each dog. Upper airway obstruction was clinically improved in two dogs.
Phreatophytic vegetation responses to groundwater depth in a drying mediterranean‐type landscape
Authors: Sommer B. , Froend R.
Published: April 2014

Questions

Does the plant hydrotype composition of phreatophytic vegetation alter with drawdown of the water table? Can alternative states of phreatophytic vegetation be identified, and do they persist despite a multi‐decadal drying of a mediterranean‐type landscape?

Location

Field study, coastal sandy plain, Gnangara Groundwater System, south‐western Australia.

Methods

We used a data set spanning 35 yr to determine alternative states of phreatophytic vegetation and how they relate to spatial variation and temporal change in hydrological habitat. Multivariate regression trees (MRT) were used to identify the range in depth to groundwater associated with vegetation states (characteristic hydrotype compositions). Logistic regression analyses were conducted to predict the proportional representation of each hydrotype. Hydrotype compositions of recent observations were correlated against modelled values derived from historic observations to test whether the relationship between vegetation states and supporting hydrological habitats remains valid after significant decline in the water table.

Results

The MRT analyses for the historic and recent observations produced a main split criterion at 2.0 and 2.9 m groundwater depth, respectively, essentially dividing records into those dominated by hydrophytes or xerophytes. No hydrophytes were present at groundwater depths >10.5 m (>8.5 m for recent observations), where xerophytes and generalists were dominant. Only extreme groundwater depths were dominated by a single hydrotype class (hydrophytes or xerophytes), while intermediate clusters represented a transition across the hydrotype classes. The logistic regressions of the proportion of hydrotypes as a function of groundwater depth resulted in good fits for hydrophytes and xerophytes only.

Conclusions

Vegetation states were consistent over 35 yr of progressive increase in depth to water table. Distribution of alternative states along a gradient in groundwater depths was exponential and was reflected in the distribution of hydrophytes and mesophytes. The ranges of groundwater depths at which individual states occur suggest that as groundwater depth increases, the degree of habitat specificity decreases. The narrow range of groundwater depths within which hydrophytes and mesophytes are dominant suggests that small changes in depth could lead to transitions between states. With ongoing drying of the landscape, persistence of these vegetation states can be expected to diminish.
Fatigue and pruritus at onset identify a more aggressive subset of primary biliary cirrhosis
Authors: Quarneti Chiara , Muratori Paolo , Lalanne Claudine , Fabbri Angela , Menichella Rita , Granito Alessandro , Masi Chiara , Lenzi Marco , Cassani Fabio , Pappas Georgios , Muratori Luigi
Published: April 2014

Background & Aims

In recent years, primary biliary cirrhosis is mostly diagnosed in patients who are asymptomatic; however, a proportion of cases still present with typical complaints such as fatigue and/or pruritus. We compared biochemical, histological and immunological features of patients with or without fatigue and/or pruritus at onset to see whether the different clinical presentation may eventually impact on disease progression.

Methods

We analysed the Bologna cohort of 216 patients with primary biliary cirrhosis referred to our Centre between 1997 and 2007, according to symptomatic (fatigue and/or pruritus) or asymptomatic presentation. Clinical, biochemical, histological and immunological feature at diagnosis, response to ursodeoxycholic acid and progression of the disorder were compared after a mean follow‐up of 81 ± 75 months.

Results

At diagnosis, symptomatic patients were significantly more often women (98.6% vs. 87.2%, P = 0.004), younger (mean age 49 ± 12 vs. 55 ± 12 years, P = 0.003) and with more pronounced biochemical activity, as indicated by higher alkaline phosphatase (mean 2.93 ± 2 vs. 2.12, P = 0.002) and aminotransferase (mean 1.92 ± 1 vs. 1.47 ± 1.27, P = 0.014) levels, whereas histological stage and autoantibody profile were similar. Symptomatic patients were less likely to respond to ursodeoxycholic acid therapy (63% vs. 81%, P = 0.006) and developed more often cirrhosis and its complications (31% vs. 13%, P = 0.004).

Conclusions

Fatigue and/or pruritus at onset identify a subset of patients with primary biliary cirrhosis who preferentially are women, younger, with a particularly active disease, less responsive to ursodeoxycholic acid treatment, and more inclined to evolve to cirrhosis and its complications.
Prospects for Moral Epistemic Infinitism
Authors: Aikin Scott F.
Published: April 2014

This article poses two regresses for justification of moral knowledge and discusses three models for moral epistemic infinitism that arise. There are moral infinitisms dependent on empirical infinitism, what are called “piggyback” moral infinitisms. There are substantive empiricist moral infinitisms, requiring infinite chains of descriptive facts to justify normative rules. These empiricist infinitisms are developed either as infinitist egoisms or as infinitist sentimentalisms. And, finally, there are substantive rationalist moral infinitisms, requiring infinite chains of normative reasons to justify moral rules. Rationalist moral infinitism is posed as a mixed view integrating moral intuitions with the demand for justifying reasons.
Positism: The Unexplored Solution to the Epistemic Regress Problem
Authors: Engel Mylan
Published: April 2014

As we trace a chain of reasoning backward, it must ultimately do one of four things: (i) end in an unjustified belief, (ii) continue infinitely, (iii) form a circle, or (iv) end in an immediately justified basic belief. This article defends positism—the view that, in certain circumstances, type‐(i) chains can justify us in holding their target beliefs. One of the assumptions that generates the epistemic regress problem is: (A) Person S is mediately justified in believing p iff (1) S has a doxastic reason q for p and (2) S is justified in believing q. Assumption (A) presupposes that reasoning is only justification transmitting, not justification generating. The article rejects (A) and argues that, in certain circumstances, reasoning itself is justification generating, even if that from which one is reasoning is not itself justified. It concludes by comparing positism with its infinitist, coherentist, and foundationalist rivals, acknowledging what is right about these other views.
Finite Reasons Without Foundations
Authors: Poston Ted
Published: April 2014

This article develops a theory of reasons that has strong similarities to Peter Klein's infinitism. The view it develops, Framework Reasons, upholds Klein's principles of avoiding arbitrariness (PAA) and avoiding circularity (PAC) without requiring an infinite regress of reasons. A view of reasons that holds that the “reason for” relation is constrained by PAA and that PAC can avoid an infinite regress if the “reason for” relation is contextual. Moreover, such a view of reasons can maintain that skepticism is false by the maintaining that there is more to epistemic justification than can be expressed in any reasoning session. One crucial argument for Framework Reasons is that justification depends on a background of plausibility considerations. The final section of the article applies this view of reasons to Michael Bergmann's argument that any nonskeptical epistemology must embrace epistemic circularity.
Metaphysical Infinitism and the Regress of Being
Authors: Morganti Matteo
Published: April 2014

This article offers a limited defense of metaphysical “infinitism,” the view that there are, or might be, infinite chains of ontological dependence. According to a widespread presupposition, there must be an ultimate ground of being—most likely, a plurality of fundamental atoms. Contrary to this view, this article shows that metaphysical infinitism is internally coherent. In particular, a parallel with the debate concerning infinitism about epistemic justification is suggested, and an “emergence model” of being is put forward. According to the emergence model, the being of any given entity gradually arises out of an infinite series of progressively less dependent entities—it is not wholly transmitted, as it were, from a basic, ungrounded level to all the dependent ones in a step‐by‐step fashion. Some objections are considered and rebutted.
PUBLIC SERVICE MOTIVATION IN THE POST‐COMMUNIST STATE
Authors: HOUSTON DAVID J.
Published: April 2014

How well does public service motivation apply to occupational locus and focus in the post‐communist state? Survey data from theISSP2005 Work Orientations module gathered in five post‐communist Central and Eastern European countries and Russia are examined using multilevel binary logistic regression analysis. It is found that occupational focus is a more important correlate of public service motivation than is occupational locus in these post‐communist countries. Because the relative importance of work motives varies across countries, it is important to account for national context when developing a theory of public service motivation.
Are Bald‐Faced Lies Deceptive after All?
Authors: Fallis Don
Published: April 2014

According to the traditional philosophical definition, you lie if and only if you say something that you believe to be false and you intend to deceive someone into believing what you say. However, philosophers have recently noted the existence of bald‐faced lies, lies which are not intended to deceive anyone into believing what is said. As a result, many philosophers have removed deception from their definitions of lying. According to Jennifer Lackey, this is ‘an unhappy divorce’ because it precludes an obvious explanation of the prima facie wrongness of lying. Moreover, Lackey claims that there is a sense of deception in which all lies are deceptive. In this paper, I argue that bald‐faced lies are not deceptive on any plausible notion of deception. In addition, I argue that divorcing deception from lying may not be as unhappy a result as Lackey suggests.
Haemodynamic changes in pulmonary hypertension in patients with interstitial lung disease treated with PDE‐5 inhibitors
Authors: Zimmermann Gregor S. , von Wulffen Werner , Huppmann Patrick , Meis Tobias , Ihle Franziska , Geiseler Jens , Leuchte Hanno H. , Tufman Amanda , Behr Juergen , Neurohr Claus
Published: April 2014

Background and objective

Interstitial lung diseases (ILD) are often associated with pulmonary hypertension (PH). This study aimed to evaluate the therapeutic benefit of phosphodiesterase‐5 (PDE‐5) inhibitors in pulmonary hypertension secondary to ILD.

Methods

Patients with ILD and PH were treated with sildenafil or tadalafil. Right heart catheterization was performed before and after a minimum of 3‐month treatment. In addition, lung function, 6‐min walk distance (6MWD) and plasma brain natriuretic peptide (BNP) concentration were assessed.

Results

Ten ILD patients (three female, mean age 64.4 ± 9.0 years, six with idiopathic pulmonary fibrosis (IPF), four with hypersensitivity pneumonitis, (HP)) with significant precapillary PH (mean pulmonary artery pressure (PAPm) ≥ 25 mmHg, pulmonary vascular resistance (PVR) > 280 dyn*s*cm−5; pulmonary artery wedge pressure (PAWPm) ≤ 15 mmHg) were treated with either sildenafil (n = 5) or tadalafil (n = 5). Pulmonary haemodynamics were severely impaired at baseline (PAPm 42.9 ± 5.4 mmHg; cardiac index (CI) 2.7 ± 0.6 L/min/m2; PVR 519 ± 131 dyn × sec × cm−5). After mean follow‐up of 6.9 ± 5.8 months an increase in CI (2.9 ± 0.7 L/min/m2, P = 0.04) and a decrease in PVR (403 ± 190 dyn × sec × cm−5, P = 0.03) were observed. 6MWD and BNP did not change significantly.

Conclusions

Our data suggest that treatment with PDE‐5 inhibitors improves pulmonary haemodynamic patients with PH secondary to ILD.
Cytokine concentration in stored canine erythrocyte concentrates
Authors: Corsi Raffaella , McMichael Maureen A. , Smith Stephanie A. , O'Brien Mauria , Herring Jennifer , Ngwenyama Thandeka R. , Galligan Alyssa , Beloshapka Alison N. , Deng Ping , Swanson Kelly S.
Published: April 2014

Objective

To evaluate the effect of leukoreduction (LR) as compared to standard nonleukoreduced (NLR) units on cytokine concentrations in canine erythrocyte concentrates during regular storage time.

Design

Randomized, experimental study.

Setting

University teaching hospital.

Animals

Ten random‐source research dogs.

Interventions

One unit of whole blood was collected from each dog and randomized to standard processing (NLR, n = 5) or prestorage LR (n = 5). All units were stored at 4°C. Samples were aseptically collected from each unit weekly for 5 weeks. On day 35, 1 mL of blood was collected from each unit and submitted for aerobic culture.

Measurement and Main Results

An ELISA assay was used to analyze the concentrations of IL‐1β, IL‐8, TNF‐α, and IL‐10. There were no significant effects of either group or storage time for IL‐1β, IL‐10, or TNF‐α. IL‐8 concentration was significantly increased over the storage period in NLR units, and was significantly higher compared to LR units on days 28 and 35. Aerobic culture was negative on all units.

Conclusions

This study demonstrated a marked, storage time‐dependent accumulation of IL‐8 in canine erythrocyte concentrates. Prestorage LR attenuated the accumulation of IL‐8. This chemokine may contribute to the proinflammatory effects of transfusion of stored erythrocyte concentrates.
Reference intervals and age‐related changes for venous biochemical, hematological, electrolytic, and blood gas variables using a point of care analyzer in 68 puppies
Authors: O'Brien Mauria A. , McMichael Maureen A. , Le Boedec Kevin , Lees George
Published: April 2014

Objective

To determine the reference interval for various venous analyte concentrations using a point‐of‐care (POC) analyzer in healthy, 4–84‐day‐old puppies and identify any age‐specific variations in the values as compared with adults.

Design

A prospective cohort study.

Setting

University teaching hospital.

Animals

Clinically healthy dogs; 68 puppies and 30 adults.

Measurements and Main Results

Samples were collected by jugular venipuncture from 68 clinically healthy puppies at 4, 10, 12, 16, 28, 70, 77, and 84 days of age and once each from 30 clinically healthy adult dogs. Blood samples (n= 287) were analyzed within 5 minutes of collection using an automated POC analyzer.Reference intervals for puppies at various ages were estimated using a bootstrap sampling approach.

The analytes that were closest to the adult values were pH and bicarbonate. On days 4 and 10 the pH for puppies was higher than the adults while the HCO3was higher than the adults only on day 4. HCT on day 4 approximated adult values but fell to a nadir on day 28 before rising toward adult levels. At all time points, sodium, chloride, and ionized magnesium concentrations were lower than adult values, and potassium and ionized calcium were higher than adult values. Glucose was similar to adult values on day 4 but was above adult values at all other time points. Blood urea nitrogen (BUN) was higher in puppies until day 28 when it became lower than in adults. BUN levels remained lower than adults through day 84.

Conclusions

Variations exist between puppies and adults for venous POC analyzer results. Adult reference intervals should not be used for puppies as this might cause misinterpretation of the results.
A generalization of Ohkawa’s theorem
Authors: Casacuberta Carles , Gutiérrez Javier J. , Rosický Jiří
Published: April 2014

A theorem due to Ohkawa states that the collection of Bousfield equivalence classes of spectra is a set. We extend this result to arbitrary combinatorial model categories.
Investigations on the Effect of Coating Material and Method on Die Wear in Stamping of Advanced High Strength Steels
Authors: Cora Ömer Necati , Koç Muammer , Blau Peter J. , Namiki Kunio
Published: April 2014

Despite the advantages of advanced high strength steels (AHSS), their stamping into functional lightweight parts demands prolonged die life, which necessitates the use of alternative substrates, coating materials, and/or surface conditioning to minimize and delay the die wear. In order to avoid frequent die replacement and surface quality problems on the stamped parts, the metalworking industry has been investigating various approaches such as reducing/refining the carbide particles, adding alloying elements, and elevating the hardness and toughness values for both substrate materials and coatings.

The objective of this work was to investigate the effects of different coatings on the wear behavior of a some selected tool steel materials (die sample of interest) against two different AHSS sheet blanks through a cylinder-on-flat type reciprocating test method. After wear tests, both die sample and sheet blank surface were microscopically examined. Wear resistance of the slider was quantified from wear scar width measurements. Results showed that TD and CVD coated die samples performed better than the two other PVD coated samples.
Arithmetic and Experimental Study of Fix-Length Compensation Based on Conical Bottom Shape of Electrode in Micro-EDM
Authors: Pei Jingyu , Zheng Bowen , He Lei , Jin Fangjin
Published: April 2014

Micro-electrical discharge machining (EDM) milling with a simple-shaped electrode is an effective machining method to fabricate three-dimensional micro parts and micro structures. However, the serious electrode wear occurring in the machining process significantly deteriorates the geometrical accuracy of the products. Fix-length compensation method is a real-time and effective electrode compensation method. During the EDM process with fix-length compensation, the bottom of cylindrical electrode trends to be conical shape. The formation process of conical electrode is illustrated by experiments and analysis. Once the cone angle of the electrode is formed, the angle of conical electrode keeps stable. Further experiments reveal the relationship between the cone angle and the layer thickness. The experiment results are in accordance with theoretical results, which provide theoretical reference for ED-milling compensation. The wear model based on fix-length compensation method with conical electrode is established and the corresponding arithmetic of compensation length is derived. Experiments show that the arithmetic equation about compensation length has high accuracy. A demonstration cavity is machined with this compensation method. The effectiveness of this compensation method is verified.
Optimization of Cutting Parameters in Turning of AISI 1018 Steel With Constant Material Removal Rate Using Robust Design for Minimizing Cutting Power
Authors: Camposeco-Negrete C. , Calderón-Nájera J. , Miranda-Valenzuela J. C.
Published: April 2014

Environmental and energy efficiency awareness of manufacturers and customers along with high electricity costs have promoted the development of strategies to reduce energy consumption in manufacturing processes. Machine tools are one of the main contributors to energy consumption in the industrial sector. Several studies have been undertaken to optimize the cutting parameters in order to minimize the power consumed in the removal of material. However, these studies do not consider the influence that different combinations of cutting parameters can have on power consumption at a constant material removal rate, quantity that has a direct influence in production rates. This paper describes an experimental study of AISI 1018 steel turning under roughing conditions and constant material removal rate, in order to obtain the cutting parameters that minimize power consumption. Robust design is used to analyze the effects of the depth of cut, feed rate and cutting speed on electric power consumed.
Formability Prediction for Thermal Stamping of Magnesium Alloy Sheet Based on M-K Model
Authors: Chen Z. H. , Wen Y. , Sun C. H.
Published: April 2014

Sheet metal stamping processes play an important role among the mechanical manufacturing operation, since they are characterized by high productivity and reliability at low cost, low material waste and almost net shapes from design. In this study, based on the Marciniak and Kuczynski (M-K) model and the forming limit diagrams (FLD), the formability prediction for thermal stamping of magnesium alloy sheet has been carried out by means of the commercial finite element analysis software ABAQUS. Moreover, related experiments of thermal stamping were also performed to validate the model. The comparison between the numerical result and experimental observation shows a good agreement. Therefore, it may indicate that the presented approach can be employed in formability prediction of thermal sheet metal forming process.
Application of Optical Scanning and Photogrammetry for Evaluation of Geometrical Tolerance Values
Authors: Gessner Andrzej , Staniek Roman , Michałek Jakub
Published: April 2014

The hereby presented research, funded by the restricted grant LIDER, NCBiR, deals, in part, with the identification of the full implementation potential of the proposed optical measurement techniques in determination of surface flatness parameters, and their comparative assessment. The test methods included the photogrammetric measurement technique (TRITOP, GOM) and the structural light scanning approach (scanner ATOS, GOM), while the CMM measurement (DEA Global Image Clima) was the reference method. The accordingly designed and assembled experimental test stand comprised 2 steel plates. The test surfaces of the plates were appropriately ground; subsequently, the entire test stand was blackened to ascertain efficient optical scanning. Furthermore, the plates were connected by means of 8 screws, thus introducing considerable distortion. A measurement area of 140 × 240 mm was defined on the plate test surface, as determined by CMM, denoting 15 measurement paths of 240 mm in length, distributed every 10 mm, and characterized by measurement point densities of 1, 5, and 20 pt/mm. The reference CMM measurements were conducted on 3 consecutive days at different times (22 measurements in total) to exclude any possible surface modifications. Subsequently, optical scanning was applied and the measurement points lying at the cross-sections of the CMM measurement paths were isolated from the obtained polygon mesh. To further apply the photogrammetric method, the test surface was labeled with markers distributed every 10 mm and coinciding with the CMM measurement paths.

Comparative analysis of the flatness parameter for the selected CMM measurement and the measurement values obtained by means of the tested optical methods included:

- the entire measurement area,

- the sections comprising 80, 60, 50, 45, 40, 30, 20, 15, and 10 % of the entire measurement area, decreasing centrically,

- the measurement sub-areas of 30 × 50 mm allotted in the corners and in the center of the test plate.

The photogrammetric error of the tested parameter was established at 1.26–19.82 %, depending on the size of the measurement area. The corresponding error value, as determined by the structural light scanning technique, amounted to 0.03–4.31 %.
A Control System Design for Efficiently Operating Free-Motion of Servo Mechanical Press
Authors: Chen Pin-Jyun , Cheng Pi-Ying , Lin Yu-Ting , Cheng Tseng-Jen
Published: April 2014

Servo press has the ability to improve the formability, quality, and productivity of metal products by working with various forming curves of slide. However, the operations of free-motion function are not very intuitional and efficient for most of servo presses so that it is difficult for operator to construct self-design forming curves. This article proposed a control system design of servo mechanical press which consists of an open-system controller and a real-time operating system to provide a convenient and efficient approach for operating free-motion function. In the proposed control system, operators determine the motion of slide by adjusting several control points of forming curve in a friendly and graphical interface. Then a calculating process based on the B-spline and curve fitting theories is applied in the controller to transform settings of operator into speed commands of servo motor automatically. Through this process, the controller is capable of driving servo motor smoothly and generating an expectant forming curve. In the latter section, some compare and analyses of setting of operator and actual results are demonstrated to verify the performance of proposed control system. By applying the proposed control system design to servo mechanical press, operators are able to create practical and satisfying forming curves more easily.
Finite Element Simulation of Cutting Forces in Turning Ti6Al4V Using DEFORM 3D
Authors: Satyanarayana Kosaraju , Venu Gopal Anne , Bangaru Babu Popuri
Published: April 2014

Titanium alloys are widely used in aerospace industry due to their excellent mechanical properties though they are classified as difficult to machine materials. As the experimental tests are costly and time demanding, metal cutting modeling provides an alternative way for better understanding of machining processes under different cutting conditions. In the present work, a finite element modeling software, DEFORM 3D has been used to simulate the machining of titanium alloy Ti6Al4V to predict the cutting forces. Experiments were conducted on a precision lathe machine using Ti6Al4V as workpiece material and TiAlN coated inserts as cutting tool. L9 orthogonal array based on design of experiments was used to evaluate the effect of process parameters such as cutting speed and feed with a constant depth of cut 0.25 mm and also the tool geometry such as rake angle on cutting force and temperature. These results were then used for estimation of heat transfer coefficient and shear friction factor constant, which are used as boundary conditions in the process of simulation. Upon simulations a relative error of maximum 9.07% was observed when compared with experimental results. A methodology was adopted to standardize these constants for a given process by taking average values of shear friction factor and heat transfer coefficient, which are used for further simulations within the range of parameters used during experimentation. A maximum error of 9.94% was observed when these simulation results are compared with that of experimental results.
Fracture Mechanics Analysis of Aero-Engine Compressor Disc
Authors: Kumar K. M. Sathish , Prakash G. V. Naveen , Kumar K. K. Pavan , Lakshminarayana H. V.
Published: April 2014

Fracture is a natural reaction of solids to relieve stress and shed excess energy. The design philosophy envisions sufficient strength and structural integrity of the aircraft to sustain major damage and to avoid catastrophic failure. However there are inherent limitations in the methodology, resulting in significant under utilization of component lives and an inability to account for non-representative factors. Ductile materials used in aircraft engine are likely to experience fatigue and stable crack growth before the occurrence of fast fracture and final failure. Fatigue crack propagation can be characterized by a crack growth-rate model that predicts the number of loading cycles required to propagate a fatigue crack to a critical size. Stress Intensity Factors under fatigue loading are below the critical value for quasi-static or unstable crack propagation. Under these circumstances, Linear Elastic Fracture Mechanics helps to characterize the crack growth-rate model. Stable crack growth and final failure generally occur at the very last loading cycle of the life of aircraft. Crack propagation at this stage involves elastic-plastic stable tearing followed by fast-fracture. Since crack growth is no longer under small-scale yielding conditions, Elastic-Plastic Fracture Mechanics is needed to characterize the fracture behavior and to predict the residual strength. The most likely places for crack initiating and development are bolt holes in a compressor disk. Such cracks may grow in time leading to a loss of strength and reduction of the life time of the disc. The objective of this work is to determine Stress Intensity Factor for a crack emanating from a bolt hole in a disk and approaching shaft hole. The objective is achieved by developing a 2D finite element model of a disk with bolt holes subjected to a centrifugal loading. It was observed that stress concentration at the holes has a strong influence on the value of Stress Intensity Factor. Also, fatigue life prediction was carried out using AFGROW software. Different fatigue crack growth laws were compared. This provides necessary information for subsequent studies, especially for fatigue loads, where stress intensity factor is necessary for the crack growth rate determination and prediction of residual strength.
Bending Effect in Concentric Bolted Joints Under Transverse Load
Authors: Amir Yosef , Iyyanar Saravanakumar , Devali Aravind , Kumar Muniratnam
Published: April 2014

Bending stress calculation in eccentric bolted joints is a well-known process in the design of bolted joints. However, in a concentric bolted joint with transverse load, the existence of bending stress is generally not considered as critical. But in reality, there is a possibility of catastrophic failure of the bolt occurring in a concentric bolted joint as a result of the bending stress even before the joint looseness or before the bolt fracture under tension. The aim of this paper is to propose a closed form solution to predict the potential risk of this failure that could be developed particularly at moderate preload of the bolt. Three concentric bolted joint cases with M12, M10 and M8 with transverse load and external tension load were investigated; FEA and experimental results validated the closed form calculation.
Using Pyramidal Three-Roll Bending Process to Improve the Quality of Seamed Cylinders
Authors: Feng Zhengkun , Champliaud Henri
Published: April 2014

Mecano-welding can efficiently produce cylinders used in various industries. The pyramidal three-roll bending process is commonly used to produce a cylinder with non-seamed gap. However, there is a planar zone near the front and rear ends. This planar zone can be seamed with a welding process. In this paper, a numerical model is proposed to simulate the roll bending process and the welding process so that the geometrical quality of the bent cylinders can be improved. Explicit and implicit solvers are applied to the numerical modeling by using ANSYS/LS-DYNA software. The numerical model can provide a useful tool for design and optimization of the Mecano-welding process.
Machining of Non-Axisymmetric Curved Surface by Lathe Turning
Authors: Morimoto Yoshitaka , Nakagaki Katsuhiro , Kato Hideharu
Published: April 2014

A new CNC lathe driven by a linear motor has been developed to realize the machining of complex non-axisymmetric curved surfaces with rotational axis such as eccentric and spiral cylindrical volume, conical cams and artificial femoral stem. These have been realized by milling and/or grinding machines. In this case, there is a serious problem. It takes a long time to machine by milling or grinding. Furthermore, the machining point between a curved surface and a milling tool or a grinding wheel can be regarded as a single point contact just as same as lathe turning. We propose a new turning method that improves the productivity remarkably by using a driven rotary tool with its unique tool layout. In this report, the machining result of the curved surface by the proposed turning method and the feasibility are also reported.
Chip Breaking Parameter Selection for Constant Surface Speed Machining
Authors: Berglind Luke , Ziegert John
Published: April 2014

Modulated tool path (MTP) chip breaking is a lathe machining technique which produces chips of a predetermined length to reduce the risk of damage to the tool or the work piece caused by chip entanglement. Individual chips are formed by repeatedly interrupting chip formation through CNC commanded tool oscillations superimposed in the tool feed direction. Previous work has shown that the chip length and part surface finish quality are dependent on the tool oscillation frequency relative to the spindle speed (OPR), and the oscillation amplitude relative to the global feed per revolution (Raf).

Apart from chip length and surface quality, the dynamic capabilities of the machine must be considered when selecting MTP parameters, OPR and Raf. The dynamic limitations of the machine will limit the available range of tool oscillation frequencies and amplitudes. In this paper, the factors which affect the MTP parameter selection process are discussed, and a process for selecting these parameters automatically based on multiple constraints and criteria is presented for constant surface speed MTP machining.
Toward the Ideal of Automating Production Optimization
Authors: Michaloski J. , Proctor F. , Arinez J. , Berglund J.
Published: April 2014

The advent of improved factory data collection offers a prime opportunity to continuously study and optimize factory operations. Although manufacturing optimization tools can be considered mainstream technology, most U.S. manufacturers do not take full advantage of such technology because of the time-intensive procedures required to manually develop models, deal with factory data acquisition problems, and resolve the incompatibility of factory and optimization data representations. Therefore, automated data acquisition, automated generation of production models, and the automated integration of data into the production models are required for any optimization analysis to be timely and cost effective. In this paper, we develop a system methodology and software framework for the optimization of production systems in a more efficient manner towards the goal of fully automated optimization. The case study of an automotive casting operation shows that a highly integrated approach enables the modeling and simulation of the complex casting operation in a responsive, cost-effective and exacting nature. Technology gaps and interim strategies will be discussed.
Effect of Laser Peening on Steel and Titanium Alloy for Power Applications
Authors: Pant Bharat K. , Prakash Raghu V. , Kamaraj M.
Published: April 2014

Low pressure steam turbine (LPST) blades are made of martensitic stainless steel and Ti6Al4V alloy for the different ratings of steam turbines due to their high strength and toughness. These blade roots have a fir tree profile and experience severe stress concentrations all along their notched sections during turbine operation. The fatigue life of these blades can be increased by introducing compressive stresses either by shot peening or by laser peening. The present work deals with laser peening of these two materials to understand its effect on their fatigue properties, surface roughness and hardness. It is observed that laser peening has significantly enhanced fatigue life of Ti6Al4V alloy at 550 MPa stress as compared to the shot peened sample. The penetration depth of residual stress due to laser peening in the Ti6Al4V alloy was twice that due to shot peening. However, the fatigue life of steel was found to be similar for both the shot peened as well as laser peened samples. Similar response was observed from testing at lower stresses (400 MPa). Since the depth of penetration of compressive residual stresses for both the laser peened as well as the shot peened samples were similar for steels, it can be concluded that the fatigue life is a strong function of the penetration depth.
Magnetic Non-Contact Harmonic Drive
Authors: Perez-Diaz J. L. , Diez-Jimenez E. , Cristache C. , Valiente-Blanco I. , Alvarez-Valenzuela M. A. , Castro V. , Ruiz-Navas E. M. , Sanchez-Garcia-Casarrubios J. , Ferdeghini C. , Canepa F. , Hornig W. , Carbone G. , Plechacek J. , Amorin A. , Serrano J. , Sanz V.
Published: April 2014

The MAGDRIVE project, granted by the Space program of the EU-FP7, is developing a gear able to produce reduction ratios from 1 to several hundreds by means of magnetic teeth. The teeth, unlike the conventional gears, do not touch one to other. This makes that this gear does not need any kind of lubrication.

In case that the maximum torque is passed over the axle simply clutches, but nothing breaks down. Therefore, it has an intrinsic antijamming characteristic. It is also reversible: it can reduce but also multiply the velocity. It can also go clockwise or anticlockwise. Ratio, maximum torque, stiffness and damping can be customized. Even more it can also be customized to be direct or inverted (inverting the sense of the rotation). A low noise level is also a remarkable feature of this kind of device.

These characteristics make this technology very attractive for a number of different fields like aerospace, automation, automotive and others.

Two different prototypes have been developed: the first one is a “room-temperature prototype” for working temperature from −40°C to 100°C, while the second one is a “cryogenic prototype” that can work at temperature as low as 70 K.

The results of the tests for the first prototype are shown in this work.
The Blade Releasing Method for Test of Engine Casing Containment
Authors: Lepeshkin Alexander , Bychkov Nikolai , Vaganov Peter , Nozhnitsky Yuri , Baluev Boris
Published: April 2014

When designing aviation gas turbine engines, check for fan casing penetrability is envisaged by normative documents. Modern calculated methods of forecasting casing containment capabilities use a set of a priori limitations, and these methods can not give a reliable assessment of this event. Experimental checkup of casing containment capability of aero engines is one of the most important tasks with respect to ensuring flight safety. When the engine blade is released in the aircraft, serious damages of the frame may occur, as well as engine mount release, fire, e.t.c., which cause catastrophic effects. To decrease expenses for the engine operational development and to solve the mentioned problems it is purposeful to carry out stage-by-stage tests of the engine components on a spin rig. One of these problems, namely, localization of blade rupture inside the engine casing, is solved by carrying out fan casing containment test on the spin rig.

The blade releasing method is proposed for casing containment test on the spin rig. It’s necessary to make calculations to determine conditions of the controlled blade-off under effect from centrifugal loads at a specified speed.

The developed blade releasing method at tests has the following stages:

1. The computational modelling performed to determine the parameters of the cropped section of the blade: the dimensions of the edges and central part of the blade for achieving of the minimal safety factor.

2. Cutting of the blade.

3. Balancing of a rotor with the undercut blade.

4. The casing with the working wheel is set on the spin rig.

5. Testing:

5.1. The specified speed of rotation of a rotor achieved.

5.2. The central part of the undercut blade section heated up. The safety factor of the blade decreases when the temperature rises. The central part of the undercut blade section extended at the rise of the temperature and centrifugal force transferred to the edges of the blade. The blade edges broke. Then centrifugal force transferred to the central part of the blade and the blade released on the specified speed.

5.3. The analysis of the test results.

The results of calculations of the rotor blade release conditions using finite element analysis and fan casing containment test are presented in this paper.
Evaluation of Forces, Tool Wear and Surface Finish During Orthogonal Machining AISI 1020 Steel in Three Cutting Environments
Authors: Chandrasekaran Vishnu Vardhan , Payton Lewis N.
Published: April 2014

A large statistically designed orthogonal tube turning experiment measuring the forces, tool wear and surface finish involved in machining of AISI 1020 steel under four different cutting environments. The environments studied were nitrogen and cold compressed air against dry machining. Each data run consisted of one minute cutting time at two different feeds of 0.002″/rev. and 0.004″/rev. at a constant depth of cut of 0.125″ width of cut using High speed steel tool material inserts. Post-mortem analysis was carried out under a Keyance microscope to evaluate the wear on the rake face. The cutting force and the thrust force are collected during the machining process with a dynamometer and the data is further processed using Labview software. The surface finish on the work piece after the cutting process is also evaluated based on the average roughness measurement taken from a contact type profilometer. The advantages of using such gaseous cutting fluids are discussed.
Modeling Multi Operator-Multi-UAV (MOMU) Operator Attention Allocation Problem
Authors: Verma Anoop , Rai Rahul
Published: April 2014

This paper addresses the operator-task attention allocation problem in multiple operators managing multiple unmanned aerial vehicles (MOMU) setting. Previous works related to UAV operator-task attention allocation are mainly focused on single operator single UAV (SOSU) or single operator multiple UAVs (SOMU) models with emphasis on reward maximization only. Present research addresses two important issues viz. multi-operator paradigm, and workload imbalance in MOMU task attention allocation problem. Assigning multiple operators to multiple UAVs can improve the flexibility of human-system decision making. This added flexibility comes at a cost of added modeling complexity. Specifically, we consider important issue of operator workload imbalance in a team setting. We model workload imbalance in MOMU setting and through computational simulations show a balance between reward maximization and operators’ workload minimization is possible.
Assessment of Microgrooved Cutting Tool in Dry Machining of AISI 1045 Steel: A Numerical Study
Authors: Ma J. , Duong Hung , Lian Yunsong , Lei Shuting
Published: April 2014

This paper studies the performance of microgrooved cutting tool in dry orthogonal machining of mild steel (AISI1045 steel) using Finite Element (FE) simulation to gain insights into how to improve performance of cutting tools. Microgrooves are designed on the rake face of tungsten carbide (WC) cutting inserts. The purpose is to test the effect of microgroove textured tools on machining performance and to compare it with non-textured cutting tools. Specifically, the following groove parameters are examined: groove width, groove depth, edge distance (the distance from cutting edge to the first groove). Their effects are assessed in terms of cutting force and thrust force. It is found that microgrooved cutting tools generate lower cutting force and thrust force and consequently lower the energy necessary for machining. The groove width, groove depth, and edge distance have big influence on the cutting force and thrust force. Consequently, this research provides insightful guidance for optimizing cutting tools.