bluuebunny/crossref_metadata_2025 huggingface dataset:
An Experimental Evaluation for Four Multiaxial Fatigue Approaches
Authors: Jin Dan , Tian Da Jiang , Wu Qi Zhou , Lin Wei
Published: September 2014

A series of tests for low cycle fatigue were conducted on the tubular specimens for 304 stainless steel under variable amplitude and irregular axial-torsional loading. Rainflow cycle counting and linear damage rule are used to calculate fatigue damage and four approaches, e.g. SWT(Smith-Watson-Topper), KBM(Kandil-Brown-Miller), FS(Fatemi-Socie), and LKN(Lee-Kim-Nam) approach are employed to predict the fatigue life. The maximum shear strain plane, the maximum normal strain plane, and the maximum damage plane are considered as the critical plane, respectively. The effects of the choice of the critical plane on previous approaches are discussed. It is shown that comparing with the maximum shear/normal strain approach, the predictions are improved by using the maximum damage plane approach, part nonproportional paths for SWT, AV and part nonproportional paths for KBM, TV paths for FS. But for LKN, the prediction results are nonconservative for some paths than that of the maximum shear/normal strain approach.
Multi-Scale Mechanical Property Characterisation of Quasi-Brittle Filter Graphite
Authors: Liu Dong , Heard Peter J. , Flewitt Peter E.J. , Smith David J.
Published: September 2014

In this paper PG25 filter graphite is characterised using mechanical tests conducted over a range of specimen length-scales from the centimetre (three-point bending and Brazilian disc compression) to the micrometre (micro-scale cantilever bending in a FEI Helios dualbeam work station). However, high resolution 3D tomography has revealed that apart from the known millimetre range of pores, the matrix contains a large population of micro-scale porosity. This leads to two discrete distributions of pore sizes in this material, so that a reduction in mechanical test specimen size results in sampling different proportions of the milli-and micro-scale pores. As a consequence, the measured mechanical properties such as elastic modulus, tensile strength and flexural strength change as a function of specimen size. This paper explores the potential benefits, difficulties and value of small-scale mechanical tests for this particular application.
High Temperature Fatigue Tests of a Cu-Be Alloy and Synthesis in Terms of Linear Elastic Strain Energy Density
Authors: Berto F. , Gallo P. , Lazzarin P.
Published: September 2014

The present paper summarises the results from uniaxial-tension stress-controlled fatigue tests performed at different temperatures up to 650°C on Cu-Be specimens. Two geometries are considered: hourglass shaped and plates weakened by a central hole (Cu-Be alloy). The motivation of the present work is that, at the best of authors’ knowledge, only a limited number of papers on these alloys under high-temperature fatigue are available in the literature and no results deal with notched components.The Cu-Be specimens fatigue data are re-analyzed in terms of the mean value of the Strain Energy Density (SED) averaged over a control volume. Thanks to the SED approach it is possible to summarise in a single scatter-band all the fatigue data, independently of the specimen geometry.
Fatigue Behaviour of Full Scale Flat Stiffened Aeronautic Panels
Authors: Sepe Raffaele , Armentani Enrico , Lamanna Giuseppe , Caputo Francesco
Published: September 2014

This paper concerns the experimental characterization of static and fatigue strength of a flat panel stiffened by bonded pad made of aluminum alloy. The panels were full scale and tested under both static and fatigue loads, applied by means of an in house designed and built multi-axial static and fatigue machine. The fatigue crack propagation life of the stiffened panel has been compared to that of a simple flat panel and to that of a flat panel with chemical milling pad-up, getting that the fatigue crack growth life can be significantly improved.
Freeze Drying of High Aspect Ratio Structures
Authors: Patel Mehul N. , Sirard Steve , Limary Ratchana , Hymes Diane
Published: September 2014

As semiconductor devices continue to scale down to smaller sizes, high aspect ratio (HAR) structures are required to achieve the desired device performance. As such, wet processing becomes a very challenging process step due to the capillary forces that are generated during drying. The strength of the capillary force is dependent on the surface tension and contact angle of the fluid that is being dried, as well as the feature spacing and AR. If the drying forces are too high (Figure 1), then the features may break or collapse onto each other resulting in poor device yield. Other factors affecting a structure’s susceptibility to collapse include pattern geometry and material composition [1].
Effect of DI-Water Dilution and Etchant Arm Movement on Spinning Type Wet Etch
Authors: Lee Hui Hwan , Ahn Duk Min , Lim Seung Taek , Kim Tae Sung
Published: September 2014

Recent advances in semiconductor manufacturing process progress to reduce the size of flash memory devices in order to raise the degree of integration on a wafer. Due to this the active profile of the devices is becoming smaller [1]. This reduced active profile needs more constricted oxide thickness on silicon wafer, however if the oxide thickness is out of tolerance limits, can cause the device yield drop. Up to now, numerous studies have been carried out to improve only the uniformity of etch amount, so that the thickness profile was not changed during wet etch process [2]. Nevertheless, in real conditions, it is well known that the thickness profile before wet etch is not flat, e.g. it has V (center low), Ʌ (edge low) and M type shapes, etc. Accordingly, there is a need for developing the wet etch process to achieve the flat thickness profile. Hence, this paper report the improvement in wet etch process to control the in-wafer etch amount by utilizing DI-water dilution and controlled etchant arm movement.
Metal Etch in Advanced Immersion Tank with Precision Uniformity Using Agitation and Wafer Rotation
Authors: Tice Scott , Park Chan Geun
Published: September 2014

In semiconductor wafer fabrication, etching refers to the process of removing unwanted material from wafer surface through a subtractive process. Metal etching is most commonly used in the patterning of metal films for interconnects by establishing specific connection and conduction paths and can be classified by dry etching, de-plating and dissolution of the layers on various substrates such as silicon, SiO2, Si3N4, GaAs, germanium, and sapphire. Dry etching is used to produce very precise etching of vertical channels or vias forming the device features or lines which make up the conductive path because it is anisotropic or etching in one direction. Dry etching is achieved by using chemical gases and plasma in a process chamber so dry etching tools are very large, complex and expensive to purchase and operate. De-plating is a process of electro-chemically removing metal material from the surface of the wafer to an anode by creating a difference in electrical potential between the surface to be etched/de-plated (typically cathode) and the “target” or anode where the material is to be collected. De-plating in single wafer tools has also replaced immersion processing due to the better uniformity it provides. However, De-plating single wafer tools are also very large and expensive to operate and have low throughput (wafers per hour). Dissolution/Immersion is the used of recirculated chemical baths to perform the etching process. In an immersion bath chemical is used to dissolve the metal layer that is unprotected by the mask. Immersion metal etch process has been on the decline because of its isotropic etching property and poor etch uniformity caused by non-uniform chemical flow around wafers in the tank. For the most of etch processes lateral etching is undesired because it occurs on the walls of the features and makes them thinner or misshapen. As a result, most of critical etching steps are performed by dry etching systems. However, if etch uniformity is precise, immersion etching can be used for less critical features in place of complex dry etching and de-plating.
Study of Etchants’ Diffusion into a 248 nm Deep UV Photoresist during a Wet Etch
Authors: Foucaud Mathieu , Rochat Névine , Garnier Philippe , Pargon Erwine , Tiron Raluca
Published: September 2014

Chemical etching is still preferred to plasma etching in numerous integrated circuits manufacturing steps. Indeed, it enables a better surface smoothness control, which is critical to obtain sufficient carrier mobility. During these steps, photoresist patterns protect underlying materials from etching. It is therefore mandatory to: 1) guarantee photoresist adhesion and keep patterns from being etched away; and 2) prevent surface degradation from etchants penetration down to the photoresist / material interface. To avoid this latter phenomenon, it is therefore crucial to know if etchants penetrate into the photoresist, and at which diffusion rate.
Megasonic Enhanced Photoresist Strip with DiO3
Authors: Dussault Don , Fittkau Jens , Gottschalk Christiane
Published: September 2014

Twenty years ago dissolved ozone in DIW (DiO3) found its way into the semiconductor industry as a cleaning agent. DiO3 provides an effective replacement for Piranha (H2SO4, H2O2) cleans. The fundamental chemistry of ozone based cleaning is due to direct and indirect reactions of ozone and oxygen radicals (the so-called radical pathway). Due to its high oxidation rate the radical pathway can accelerate the reaction. Megasonic energy can act as an initiator for the radical pathway. At the same time, due to the creation of turbulence inside the boundary layer, the available ozone close to the surface is increased. In the present study this chemical physical combination was tested for improvement of photoresist strip rate.
Control of HF Volatile Contamination in FOUP Environment by Advanced Polymers and Clean Gas Purge
Authors: González-Aguirre Paola , Fontaine Hervé , Beitia Carlos , Ohlsen Jim , Lundgren Jorgen
Published: September 2014

Semiconductor manufacturing technologies have developed to the point where molecules, such as water, oxygen and airborne molecular contaminants (AMCs), have become detrimental in specific process conditions. Front Opening Unified Pods (FOUPs) are designed as controlled microenvironments (MEs) that protect processed wafers from AMCs during storage and transport. However, it has been demonstrated that FOUPs are able to accumulate by sorption molecules outgassed by processed wafers. Such contaminants are then able to be subsequently released and transferred to other sensitive wafers leading to detrimental impact [1,2]. This cross-contamination scheme from FOUP to wafer was evidenced especially for volatile acids such as HF or HCl and is responsible of yield losses due to drastic corrosion issues or crystal growth on Cu, Al or TiN materials [1,3,4]. These cross contamination issues can be reduced or controlled using low sorption and outgassing polymer materials as previously reported [4,5]. Another AMC control measure is to purge the FOUP with a dry gas. This provides several advantages, for example, wafers are not easily oxidized thus preventing oxide layers, deposition of hydrocarbons and metal defects [6] However, there is no measured information about the purge impact has on AMC control inside a FOUP. The purpose of this paper is to show and quantify what effect two different FOUP polymers using nitrogen and clean dry air (CDA) purge have on the HF volatile acid control through the Cu-wafers storage.
FOUP Material Influence on HF Contamination during Queue-Time
Authors: Bounouar Julien , Nguyen Thi Quynh , Le-Barillec Olivier , Favre Arnaud , Veran Emmanuelle , Stassen Ingo , Gettel Astrid
Published: September 2014

Airborne Molecular Contamination (AMC) concentrations become critical during queue-time (between two successive process steps) when wafers are degassing inside Front Opening Unified Pod (FOUP), a confined environment [1]. In that case, AMC concentrations can reach maximum level.
Improvement of Silicon Solar Cell Substrates by Wet-Chemical Oxidation Studied by Surface Photovoltage Measurements
Authors: Angermann Heike , Laades Abdelazize , Kegel Jan , Klimm Carola , Stegemann Bert
Published: September 2014

The deposition of thin and ultra-thin layers requires extremely clean, smooth and defect-free Silicon (Si) substrate surfaces as starting point. The preparation-induced surface micro-roughness and surface coverage of the substrates often affect the initial layer growth, the morphology or the adhesion of deposited layers. Si device fabrication includes multiple wet cleaning and etching steps involving different oxidizing and etching solutions, which modify the surface electronic properties according to fixed charges and defect states present on the surface. Depending on the details of the device structure, surface conditioning methods have to be carefully optimized to achieve the desired electronic interface properties.
Single Wafer Selective Silicon Nitride Removal with Phosphoric Acid and Steam
Authors: Guo Ted , Yu Wesley , Chien C.C. , Lin Euing , Yang N.H. , Lin J.F. , Wu J.Y. , Ratkovich Anthony , Kahaian Don , Butterbaugh Jeffery W. , Lauerhaas Jeffrey M.
Published: September 2014

A single wafer silicon nitride (SiN) selective etch process with an etch rate greater than 80A/min of low-pressure chemical vapor deposited (LPCVD) SiN has been developed. Previous work with a similar single wafer system utilized a mixture of sulfuric acid, phosphoric acid and steam to achieve a high SiN etch rate [1]. The process in this work relies on phosphoric acid and steam for a high SiN etch rate. In both of these applications, addition of steam doubles the SiN etch rate. The single wafer system utilizes a closed chamber design with integrated spray bar to uniformly dispense hot phosphoric acid and steam onto the wafer surface achieving within wafer non-uniformities of less than 3%. Rinsing and drying of the phosphoric acid from the wafer surface occurs in the same chamber (dry in/dry out) providing a stable, haze free wafer. Figure 1 contains a schematic of the phosphoric acid delivery and single wafer system.
Program Directors' Perceptions of Undergraduate Athletic Training Student Retention
Authors: Bowman Thomas G. , Hertel Jay , Mazerolle Stephanie M. , Dodge Thomas M. , Wathington Heather D.
Published: September 2014

Context:

The average retention rate for students enrolled in undergraduate athletic training programs (ATPs) nationwide has been reported to be 81%, and slightly more than half of program directors (PDs) have indicated that retention of athletic training students (ATSs) is a problem. However, why PDs do or do not believe ATS retention is problematic is unknown.

Objective:

To determine why PDs do or do not believe ATS retention is problematic.

Design:

Qualitative study.

Setting:

Undergraduate ATPs.

Patients or Other Participants:

We obtained responses from 177 of the 343 PDs (51.6%). Using data saturation as a guide, we randomly selected 16 PDs from the survey responses to participate in follow-up telephone interviews; 8 believed retention was a problem and 8 did not.

Data Collection and Analysis:

During audio-recorded telephone interviews, we asked PDs why they thought retention was or was not a problem for athletic training education. Following verbatim transcription, we used grounded theory to analyze the interview data and maintained trustworthiness by using intercoder agreement, member checks, and peer review.

Results:

Program directors believed that retaining ATSs was a problem because students lack information regarding athletic training and the rigor of the ATP. Program directors were consistent in their perception that ATPs do not have a retention challenge because of the use of a secondary admissions process. This finding was likely based on personal use of a secondary admissions process in the ATPs these PDs lead.

Conclusions:

Program directors who lead ATPs that struggle to retain ATSs should consider using a secondary admissions process. During the preprofessional phase of the ATP, faculty and staff should work to socialize students to the demands of the ATP and the professional lives of athletic trainers.
A Two-Phase Flow Simulation of Discrete-Fractured Media using Mimetic Finite Difference Method
Authors: Huang Zhaoqin , Yan Xia , Yao Jun
Published: September 2014

Various conceptual models exist for numerical simulation of fluid flow in fractured porous media, such as dual-porosity model and equivalent continuum model. As a promising model, the discrete-fracture model has been received more attention in the past decade. It can be used both as a stand-alone tool as well as for the evaluation of effective parameters for the continuum models. Various numerical methods have been applied to the discrete-fracture model, including control volume finite difference, Galerkin and mixed finite element methods. All these methods have inherent limitations in accuracy and applicabilities. In this work, we developed a new numerical scheme for the discrete-fracture model by using mimetic finite difference method. The proposed numerical model is applicable in arbitrary unstructured gridcells with full-tensor permeabilities. The matrix-fracture and fracture-fracture fluxes are calculated based on powerful features of the mimetic finite difference method, while the upstream finite volume scheme is used for the approximation of the saturation equation. Several numerical tests in 2D and 3D are carried out to demonstrate the efficiency and robustness of the proposed numerical model.
Refining the Practice of Prescribing: Teaching Physician Learners How to Talk to Patients About a New Prescription
Authors: Ledford Christy J. W. , Childress Marc A. , Ledford Christopher C. , Mundy Heather D.
Published: September 2014

Background

Clinician counseling about medication can improve patient understanding and adherence. This study developed a teaching session for physician learners about medication prescribing and communication, with evaluation at the physician and patient levels.

Objective

We analyzed whether patients would perceive and report more comprehensive clinician presentation of medication information when receiving prescriptions from their physician in the intervention clinic.

Methods

We conducted a single site, prospective intervention study that included lectures, role play, an objective standardized clinical examination (OSCE), and reminders displayed in patient care areas. For physician-level assessment, pretests and posttests included a written case presentation and a OSCE. For patient-level assessment, we used a cross-sectional observational design that included study of patient recall information, and assessment of patient satisfaction before and after intervention.

Results

Twenty-seven family medicine residents and sports medicine fellows participated in the teaching session, focused on presenting patients the reasons, risks, and regimen of prescribed medication. In written testing, learners presented significantly more comprehensive information in posttests. In the OSCE (n  =  14), all learners presented risks and regimen information. However, patient-level assessment showed no significant difference between before and after intervention. Notably, the covariates patient activation and satisfaction with communication both had a significant association with patient recall information.

Conclusions

Our intervention improved learner presentation of medication information. However, patient recall of the information conveyed did not change. Although physician training did not have a positive effect on patient recall, patient activation emerged as a critical influence of patients' perceptions of medication discussions.
An Analysis of Literary Representations of Iranian Men in Diasporic Iranian Literature
Authors: Fotouhi Sanaz
Published: September 2014

Middle Eastern Muslim men have been historically subjected to stereotypical representations in the West. Although these men are categorically hypervisible for Western audiences as a similar type, among them Iranian men in particular, have been subject to a specific kind of marginalization. Following the 1979 Islamic revolution and the American hostage crisis in Iran, Iranian men and masculinity have become hypervisible as violent and religiously fanatic. While Western discourses of representation contributed greatly to the construction and representation of this specific kind of masculinity which marginalized and stigmatized Iranian men, Iranians themselves, have played a significant role in reaffirming this view. Ironically, contributing most to the reinforcement of this discourse has been Iranian women’s narratives in English in the West, in the form of memoirs and fictional accounts. These popular accounts have played a significant part in marginalizing and emphasizing a hypervisible and stereotypical representation of Iranian men. This paper considers the representation of Iranian men and masculinity as presented through Iranian women’s narratives in the West in English. By drawing on specific narratives and accounts, it examines how socio-political and historical contexts both in the West and in Iran, have led to Iranian women’s representation of Iranian men hypervisibly. Then, through an examination of some narratives by Iranian men, this paper examines how such representations have led to emphasizing the discourse of exclusion and otherness of Iranian men in the West, hampering the actual smooth integration of diasporic Iranian men into their adopted homes.
‘The Ties that Bind Us’: The Hidden Knots of Gay Marriage
Authors: Winter Bronwyn
Published: September 2014

Gay marriage has become a major transnational gay rights issue: a key marker of gay citizenship, to the extent that it is considered self-evident that its legalisation represents progress. Yet it is becoming apparent that this ‘progress’ is concurrent with other forms of exclusion. In this article, I argue that gay marriage is a convenient liberal smokescreen, leaving other exclusions unaddressed or even enabling their reinforcement. The discussion involves examination of three case studies: Argentina, the first Latin American country to legalise gay marriage in 2010; France, which legalised gay marriage in May, 2013; and Australia, which has not legalised gay marriage at the time of this writing.
Perceived Discrimination in LGBTIQ Discourse: A Typology of Verbal Discrimination
Authors: Rojas Lizana Sol
Published: September 2014

New within the field of Discourse Analysis, Perceived Discrimination (PD) is the study of discourse that focuses on the perspective of the victims of discrimination. This article explores the experiences of verbal discrimination as reported by eighteen LGBTIQ participants during semi-structured, co-constructed interviews. Data were classified in order to develop a taxonomy of discrimination based on Mellor’s (2003, 2004). This taxonomy foregrounds two types of discrimination: verbal and behavioural. In this paper, I exemplify the forms of verbal discrimination encountered and offer an analysis of the discourse used in the construction of the experiences and of the effects reported. The results show that verbal discrimination is an overt phenomenon and that participants are stressed by the ever present possibility of facing it. Verbal discrimination is mainly triggered by a perceived transgression to the normalised standards of people’s behaviour, movements and look in a heterosexist society. It presents three subtypes: name calling, abuse and remarks. These subtypes are described through the analysis of keywords, effects and expressions (such as faggot, gay, dyke, queer, the pronoun ‘it’, religious comments and other remarks). The type of discrimination used was associated with the level of acquaintance perpetrators have with the experiencers; that is, name calling was used by people unknown to the victims while abuse and remarks by acquaintances and family members. Participants resorted to several discursive strategies to convey their intentions. They used mitigation strategies when wanting to minimize the experience, hedging and repetition were used for emphasis, and to convey urgency and pervasiveness. Metaphorical expressions related to internal or external injuries were also used to express the powerful effect of verbal discrimination on people.
Rock Water Ladder Crónica; Teensy Ex-Africa Crónica; Astral Logic Crónica
Authors: Chavez-Silverman Susana
Published: September 2014

To Come
Evaluación de Quassia amara como tratamiento contra la varroosis en tres apiarios del municipio de León, Nicaragua
Authors: Esquivel FC , Mejía LL , Flores BJ , Düttmann C , Castillo GL , Argüello O , Demedio J
Published: September 2014

Se realizó un estudio experimental en tres apiarios con las mismas condiciones físicas y ambientales con el fin de evaluar la eficacia del extracto acuoso Quassia amara como tratamiento contra Varroa destructor utilizando para esto cinco grupos de tratamiento: Colmena ST: Sin tratamiento, es el control y cuatro colmenas a las que se les aplicó el extracto de Quassia amara en diferentes concentraciones: Colmena A: solución madre (M) 100% (1 kg materia bruta/10 l de agua); Colmena B: dilución I = Una parte de solución M más 4 partes de agua (20%); Colmena C: dilución II = Una parte de la dilución I más una parte de agua (10%); Colmena D: dilución III = Una parte de dilución II más una parte de agua (5%). Se realizaron seis aplicaciones mediante aspersión con intervalo de cuatro días. Los índices de infestación fueron valorados mediante conteos de la carga parasitaria en abejas adultas de cada colmena y las muestras se recolectaron en los siguientes momentos: Al realizar la primera, tercera y última aplicaciones, y 21 días después de la última. La extensión de invasión en crías se determinó en la primera y última aplicaciones y 21 días después. En total se trabajaron 60 muestras de abejas adultas de 150 a 200 especímenes y 45 fragmentos de panales de cría operculada de 10x10 cm. Se encontró que la dilución I fue la más efectiva sobre el ácaro en abejas adultas, con el mejor resultado a la cuarta semana del inicio de la aplicación (eficacia = 62%) mientras que en crías la más efectiva fue la dilución IV (eficacia = 23,10%). La planta Quassia amara brinda una alternativa prometedora de posible futura integración a las medidas con que los productores enfrentan el problema de la varroosis. La información recopilada contribuirá a la elaboración de un programa de control de esta enfermedad. DOI: http://dx.doi.org/10.5377/universitas.v5i1.1482 UNIVERSITAS (León): Revista Científica de la UNAN León Vol.5(1) 2014, pp 100-106
Study of a MEMS Vibratory Gyroscope Using Adaptive Iterative Learning Control
Authors: Lu Xiaochun , Fei Juntao
Published: September 2014

This paper proposes a framework, namely adaptive iterative learning control (AILC), which is used in the control of a microelectromechanical system (MEMS) gyroscope, to realize high-precision trajectory tracking control. According to the characteristics of the MEMS gyroscope's model, the proposed AILC algorithm includes an adaptive law of parametric estimation and an iteration control law, which is updated in the iterative domain without any prior knowledge of MEMS gyroscopes. The convergence of the method is proven by a Lyapunov-like approach, which shows that the designed controller can guarantee the stability of the system and make the output tracking errors to converge completely to zero while the iteration index tends to infinity. By comparing AILC and traditional PD-ILC, the simulation results demonstrate the effectiveness of AILC and its robustness against external random disturbance.
Media Clips: U.S. Traffic Fatalities – Moneyball
Authors: Cibes Margaret , Greenwood James
Published: September 2014

Students analyze items from the media to answer mathematical questions related to the article.
The Best Friend Mathematics Ever Had
Authors: Mulcahy Colm , Goetz Albert
Published: September 2014

A tip of the hat to the popular mathematics writer Martin Gardner.
Connecting the Dots: Rediscovering Continuity
Authors: Camenga Kristin A. , Johnson Yates Rebekah B.
Published: September 2014

A deep understanding of continuity enables teachers to help students construct a richer concept of function and attend to precision.
Mathletics Training Camp
Authors: Allen Benjamin S.
Published: September 2014

A discussion of weightlifting provides the real-life tie-in to this computation activity.
Les racines éducationnelles de l’indifférence
Authors: Dufour Emanuelle
Published: September 2014

La présente note de recherche offre une brève réflexion autour de la représentation des Premières Nations à travers le programme éducatif provincial et de ses conséquences sur la perpétuation de stéréotypes à l'intérieur du tissu social québécois. Malgré les recommandations de laMaîtriseindienne de l'éducation indienne(FIC 1972: 10-11), la marginalisation systémique a continué à s'opérer, voire à se renouveler, à travers les manuels et cursus scolaires sur un plan intergénérationnel, et l'on assiste à la création d'un large éventail d'initiatives pédagogiques, artistiques et sociopolitiques locales. L'auteure se questionne ici sur la possibilité d'aspirer à l'assainissement des relations autochtones-allochtones sans une véritable remise en question de nos propres perspectives historiques, identitaires et institutionnelles.
Analyse touristique d’un itinéraire géologique
Authors: Venzal Christel
Published: September 2014

L’étude de cas proposée dans le cadre de cette contribution se situe dans le département des Pyrénées-Atlantiques, dans le sud-ouest de la France, limitrophe de l’Espagne. Ce département, dont une partie est intégrée au Parc national des Pyrénées, propose une vingtaine de routes thématiques et compte depuis 2008 un nouvel itinéraire appelé la Route géologique transpyrénéenne. Notre hypothèse de travail appréhende, par l’étude de cet itinéraire, le point de vue de l’aménagement touristique en étudiant sept équipements, disposés le long d’un axe routier préexistant à forte circulation et au sein d’espaces publics urbains.
Des stratégies de changement dans les organisations internationales
Authors: Louis Marieke , Maertens Lucile
Published: September 2014

Partant d’une comparaison inédite entre le Haut Commissariat des Nations Unies pour les réfugiés (hcr) et l’Organisation internationale du travail (oit), cet article suggère de revisiter la problématique du changement dans les organisations internationales en montrant, dans une perspective de sociologie des relations internationales, l’existence d’un continuum de stratégies organisationnelles mises en place par ces dernières pour légitimer leur existence et leur action, stratégies allant de la survie à la revendication d’une certaine autonomie. Deux moments de la vie du hcr et de l’oit sont comparés : l’intervention, en décembre 2004, du hcr au secours de victimes du tsunami en Asie du Sud-Est et le lancement, en juin 1999, de l’Agenda du travail décent, par le directeur général de l’oit.
Cleaner Production: The Key to Waste, Water and Energy Reduction in Higher Education, Philippines
Authors: Badiola Richard A. , Morite Analyn , Ylaya Bryan , Espaldon Alexis
Published: September 2014

The fight against the worsening environmental problems has been the battle cry of the world. Environmental sustainability requires balance between development and the environment, is the key towards efficient resource management. This paper examines a Higher Education Institution through Cleaner Production Assessment, to look for viable and economic options through which the institution can enhance its environmental performance thereby can generate resources’ savings; utilizes solid waste and increase worker’s productivity. Cleaner Production assessment was successfully conducted to come up with a program for efficient cost reduction measures for water, energy and solid waste generations. The study revealed that, through Cleaner Production, about 8% monthly energy savings is expected by shutting down air-conditioned appliances one hour per day. Eighty percent can be saved on the computer’s monthly energy consumption when laptop computers are used instead of desktops. A savings of 28% on monthly water consumption if rainwater will be utilized. Monthly financial savings of not less than 180,000 pesos is expected can be attained under a sustained CP program. More than 50% of solid waste, if diverted for recycling/processing, the institution can produce at least 35,000 pesos annually. The Cleaner Production program requiring the combined effort of the stakeholders can provide huge benefits to a school institution through improved operating and maintenance practices, cleaner technology and product changes.
Design and Fabrication of Horizontal Screw Type Mixer for Livestock Feed Meal
Authors: Cajindos Jayson Reynante
Published: September 2014

Small-scale livestock raisers are in dire need of a highly nutritious poultry feed to increase production output. And efficient mixing is the next key to good feed production. The mixing time for a batch of ingredients varies according to the design of the mixer, thus designing a fabricated horizontal screw type mixer was necessitate. The horizontal screw type mixer for livestock feed meal was fabricated using metal working concepts. The main components are the housing, bucket, rotor assembly and gear box. Experimental design was made to obtain the machine performance like pulley ratio, number of paddles/ blades, and the driving gear ratio. The machine used four (4) inches diameter pulley at the gear box and seven (7) inches diameter pulley at the gear box and seven (inches) diameter pulley at the motor connecting with a V-belt, eight paddles were installed at the rotor shafting for good mixing capability. The driving gear used 18 teeth at the upper sprocket and 36 teeth at the lower sprocket to obtain past and efficient mixing of raw materials in the production of feeds. It is powered by one half horse power electric motor. The machine could produce in an average of 15 kilograms in two (3.66) minutes.
Modes of extensional faulting controlled by surface processes
Authors: Olive Jean‐Arthur , Behn Mark D. , Malatesta Luca C.
Published: September 2014

We investigate the feedbacks between surface processes and tectonics in an extensional setting by coupling a 2‐D geodynamical model with a landscape evolution law. Focusing on the evolution of a single normal fault, we show that surface processes significantly enhance the amount of horizontal extension a fault can accommodate before being abandoned in favor of a new fault. In simulations with very slow erosion rates, a 15 km thick brittle layer extends via a succession of crosscutting short‐lived faults (heave < 5 km). By contrast, when erosion rates are comparable to the regional extension velocity, deformation is accommodated on long‐lived faults (heave >10 km). Using simple scaling arguments, we quantify the effect of surface mass removal on the force balance acting on a growing normal fault. This leads us to propose that the major range‐bounding normal faults observed in many continental rifts owe their large offsets to erosional and depositional processes.
Surface slope control on firn density at Thwaites Glacier, West Antarctica: Results from airborne radar sounding
Authors: Grima Cyril , Blankenship Donald D. , Young Duncan A. , Schroeder Dustin M.
Published: September 2014

We derive the surface density variations over Thwaites Glacier from a statistical analysis of airborne High‐Capability Radar Sounder surface returns acquired in the 2004–2005 summer. We produce a 5 km gridded map with an estimated ±12.5 kg m−3 accuracy. The background pattern of densities decreases inland from ~ 480 kg m−3 to ~ 350 kg m−3. A remarkable ~ 30 km wide vein‐shaped anomaly of up to 570 kg m−3 is located ~ 100 km from the coastline. Density anomalies correspond with surface slope breaks but are not necessarily coincident with smaller slopes. They could result from complex wind‐driven snow redistribution and/or refreezing of former snowmelt. This inversion technique can significantly improve surface mass balance calculations to understanding of glacier dynamics at regional scales and is valuable to verify and improve Antarctic climate models. It is also a promising approach for future surface analysis of icy moons by planetary radars.
Solar cycle variation of plasma mass density in the outer magnetosphere: Magnetoseismic analysis of toroidal standing Alfvén waves detected by Geotail
Authors: Takahashi Kazue , Denton Richard E. , Hirahara Masafumi , Min Kyungguk , Ohtani Shin‐ichi , Sanchez Ennio
Published: September 2014

We study the variation of plasma mass density in the outer magnetosphere over a solar cycle using mass density estimated from the frequency of fundamental toroidal standing Alfvén waves observed by the Geotail spacecraft. We identify wave events using ion bulk velocity data covering 1995–2006 and use events in the 0400–0800 magnetic local time sector for statistical analysis. We find that the F10.7 index is a dominant controlling factor of the mass density. For the equatorial mass density that is normalized to the value at L = 11, we obtain an empirical formula , where the units of and F10.7 are amu cm−3 and solar flux units (sfu; 1 sfu =10−22 W m−2 Hz−1), respectively. This formula indicates that changes by a factor of 1.8, if F10.7 changes from 70 sfu (solar minimum) to 210 sfu (solar maximum). A formula derived in a similar manner using GOES magnetometer data indicates that, for the same range of F10.7, the mass density at L ∼ 7 varies by a factor of 4.1 We attribute the smaller factor at L = 11 to the lower O+/H+ number density ratio at higher L, the stronger F10.7 dependence of the O+ outflow rate than the H+ outflow rate, and entry of solar wind H+ ions to the outer magnetosphere.
What is the appropriate coordinate system for magnetometer data when analyzing ionospheric currents?
Authors: Laundal K. M. , Gjerloev J. W.
Published: September 2014

In this paper we investigate which coordinate representation is most appropriate when analyzing ground magnetometer data in terms of ionospheric currents, in particular the westward electrojet. The AL and the recently introduced SML index are frequently used as monitors of the westward electrojet. Both indices are based on ground magnetometers at auroral latitudes. From these magnetometers, the largest perturbation in the southward direction is selected as the AL/SML index at 1 min cadence. The southward component is defined as antiparallel to the orientation of the horizontal part of the Earths' main field, B0,H. The implicit assumption when using these indices as a monitor of the westward electrojet is that the electrojet flows perpendicular to B0,H. However, B0,H is, in general, not perpendicular to the westward direction in coordinate systems that take nondipole terms of the Earth's magnetic field into account, such as apex and the Altitude Adjusted Corrected Geomagnetic coordinate systems. In this paper we derive a new SML index, based on apex coordinates. We find that the new index has less variation with longitude and universal time (UT), compared to the traditionally defined SML. We argue that when analyzing ionospheric currents using magnetometers, it is appropriate to convert the components to a corrected geomagnetic system. This is most important when considering longitudinal or UT variations, or when data from a limited region are used.
Geophysical signatures for low porosity can mimic natural gas hydrate: An example from Alaminos Canyon, Gulf of Mexico
Authors: Cook Ann E. , Tost Brian C.
Published: September 2014

Natural gas hydrate in sand sediments can increase both the measured compressional velocity and resistivity. The same geophysical signatures occur, however, in low‐porosity sand. We investigate the possible occurrence of natural gas hydrate in a sand interval in Alaminos Canyon Block 21 (AC 21) in the Gulf of Mexico, drilled by the U.S. Gas Hydrate Joint Industry Project. The sand interval has an increase in resistivity (~2.2 Ω m) and a strong peak and trough at the top and bottom of the sand on exploration seismic, which has been interpreted as natural gas hydrate. We reexamine the logging data and construct a new reservoir model that matches the measured resistivity, the high‐density sublayers in the sand, and the surface seismic trace. Our model shows that the sand interval in AC 21 is most likely water saturated; and the slight increase in resistivity, higher‐measured density, and the seismic amplitudes are caused by a reduction in porosity to ~30% in the sand interval relative to a porosity of ~42% in the surrounding marine muds. More broadly, we show that the average depth where the porosity of marine muds becomes lower than sand sediment is 900 mbsf, though it could be as shallow as 600 mbsf for high‐porosity sands. In any case, the similar geophysical signatures for water‐saturated sand and low saturations of natural gas hydrate in sand probably occur throughout the gas hydrate stability zone at most sites worldwide.
Low‐Dose Extrapolation
Authors: Piegorsch Walter W.
Published: September 2014

Issues of extrapolation in risk analytic studies are reviewed for cases where the design of a study requires the data to be taken at fairly high‐dose levels, but where decisions on occupational or environmental exposure standards to a toxic agent must be extrapol ated from the high‐dose exposure data to low‐dose levels of the agent.
Error Rates
Authors: Thompson Bruce
Published: September 2014

Error rate refers to the probability of making one or more incorrect decisions regarding null hypotheses. The most commonly recognized forms of errors are Type I errors (i.e., rejecting a null that actually is true) and Type II errors (i.e., failing to reject a null that actually is false). Researchers also distinguish between making a Type I error on a given hypothesis test (called a
testwise Type I error
) and making one or more Type I errors in a set of hypothesis tests (called
experimentwise Type I error
).
A probabilistic approach to stability and stabilization of networked control systems
Authors: Zhang Jinhui , Lam James
Published: September 2014

In this paper, a probabilistic approach is proposed to study the modeling, stability, and stabilization problems for networked control systems (NCSs) with simultaneous random network communication delay and data dropout. Different from existing modeling approaches, the proposed NCSs model naturally captures the stochastic characteristics of the considered NCSs by taking into account the effects of the random network communication delay and data dropout. Based on the developed NCSs model, necessary and sufficient conditions of stability analysis, state, and output feedback stabilization problems are tackled. Moreover, necessary and sufficient stability and stabilization conditions are also presented for the case when the occurrence probabilities of delay and data dropout are partially known. Finally, three numerical examples are provided to demonstrate the effectiveness and the reduced conservatism of the proposed method. Copyright © 2014 John Wiley & Sons, Ltd.
Ruthenium(II)‐Catalyzed Protocol for Preparation of Diverse α,β‐ and β,β‐Dihaloenones from Diazodicarbonyls
Authors: Somai Magar Krishna Bahadur , Lee Yong Rok
Published: September 2014

Efficient one‐step syntheses of α,β‐ and β,β‐dihaloenones were achieved by ruthenium(II)‐catalyzed reactions between cyclic or acyclic diazodicarbonyl compounds and oxalyl chloride or oxalyl bromide in moderate to good yields. This methodology offers several significant advantages, which include ease of handling, mild reaction conditions, one‐step reaction, and the use of an effective and non‐toxic catalyst. The synthesized compounds were further transformed into highly functionalized novel molecules bearing aromatic rings on the enone moiety using the Suzuki reaction.

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Synthese von Chlorosilicaten
Authors: Steinhauer Simon , Böttcher Tobias , Schwarze Nico , Neumann Beate , Stammler Hans‐Georg , Hoge Berthold
Published: September 2014

Chlorosilicate stellen wichtige Intermediate bei SN2‐Reaktionen von Chlorsilanen dar. Sie können durch die Einführung elektronenziehender Substituenten stabilisiert werden. Salze einer Reihe von (Pentafluorethyl)chlorosilicaten wurden isoliert und strukturell charakterisiert.
Dioxygen Activation by Siloxide Complexes of Chromium(II) and Chromium(IV)
Authors: Schax Fabian , Bill Eckhard , Herwig Christian , Limberg Christian
Published: September 2014

The reaction of a tripodal trisilanol with n‐butyllithium and CrCl2 results in a dinuclear CrII complex (1), which is capable of cleaving O2 to yield in a unique complex (2) with an asymmetric diamond core composed of two CrIVO units. Magnetic susceptibility data reveal significant exchange coupling of CrII (S=2) in 1 and large zero‐field splitting for CrIV (S=1) in 2 owing to strong spin–orbit coupling of the ground state. The CrIVO compound can also be generated using PhIO, and evidence was gathered that although it is the stable product isolated after excessive O2 treatment, it further activates O2 to yield an intermediate species that oxidizes THF or Me‐THF. By extensive 18O labeling studies we were able to show, that in the course of this process 18O2 exchanges its label with siloxide O atoms of the ligand via terminal oxido ligands.
Perovskite Oxide Nanosheets with Tunable Band‐Edge Potentials and High Photocatalytic Hydrogen‐Evolution Activity
Authors: Maeda Kazuhiko , Eguchi Miharu , Oshima Takayoshi
Published: September 2014

Perovskite nanosheets of HCa2−xSrxNb3O10 and HCa2Nb3−yTayO10 with controlled band‐edge potentials were prepared. They worked as highly efficient heterogeneous photocatalysts for H2 evolution from a water/methanol mixture under band‐gap irradiation. The activity was found to depend on the composition. The highest activity was obtained with HCa2Nb2TaO10 nanosheets, recording an apparent quantum yield of approximately 80 % at 300 nm, which is the highest value for a nanosheet‐based photocatalyst reported to date.
Diversity‐Oriented Synthesis of Drug‐Like Macrocyclic Scaffolds Using an Orthogonal Organo‐ and Metal Catalysis Strategy
Authors: Grossmann André , Bartlett Sean , Janecek Matej , Hodgkinson James T. , Spring David R.
Published: September 2014

Small‐molecule modulators of biological targets play a crucial role in biology and medicine. In this context, diversity‐oriented synthesis (DOS) provides strategies toward generating small molecules with a broad range of unique scaffolds, and hence three‐dimensionality, to target a broad area of biological space. In this study, an organocatalysis‐derived DOS library of macrocycles was synthesized by exploiting the pluripotency of aldehydes. The orthogonal combination of multiple diversity‐generating organocatalytic steps with alkene metathesis enabled the synthesis of 51 distinct macrocyclic structures bearing 48 unique scaffolds in only two to four steps without the need for protecting groups. Furthermore, merging organocatalysis and alkene metathesis in a one‐pot protocol facilitated the synthesis of drug‐like macrocycles with natural‐product‐like levels of shape diversity in a single step.
Radiation field spectra of long‐duration cloud flashes
Authors: Ahmad Noor Azlinda , Baharudin Z. A. , Fernando M. , Cooray V.
Published: September 2014

The preliminary results of radiation electric fields produced by long‐duration cloud flashes have been Fourier analyzed to determine the frequency spectrum in the range of 10 kHz–10 MHz. The flashes were recorded within a distance of less than 20 km. The spectrum was normalized to 50 km distance and it shows a f−1 dependence within the entire frequency range.