bluuebunny/crossref_metadata_2025 huggingface dataset:
Sustainable and Renewable Energy: An Overview of the Application of Multiple Criteria Decision Making Techniques and Approaches
Authors: Mardani Abbas , Jusoh Ahmad , Zavadskas Edmundas , Cavallaro Fausto , Khalifah Zainab
Published: October 2015

The main purpose of this paper is to present a systematic review of MCDM techniques and approaches in sustainable and renewable energy systems problems. This study reviewed a total of 54 papers published from 2003–2015 in more than 20 high-ranking journals, most related to sustainable and renewable energies, and which were extracted from the Web of Science database. In the category of application areas, papers were classified into two main groups: (1) sustainable energy and (2) renewable energy. Furthermore, in the classification of techniques and approaches, the papers were categorized into six groups: (1) AHP and F-AHP; (2) ANP and VIKOR; (3) TOPSIS and F-TOPSIS; (4) PROMETHEE; (5) integrated methods and (6) other methods. In addition, papers were reviewed based on the authors’ nationalities, the publication date, techniques and approaches, the name of journal and studies criteria. The results of this study indicated that, in 2015, scholars have published more papers than in other years. Furthermore, AHP/fuzzy AHP and integrated methods were ranked as the first rank, with 14 papers. Additionally, Journal of Renewable Energy is the first journal, with 16 publications, and this was the most significant journal in this study. Findings of this review paper confirm that MCDM techniques can assist stakeholders and decision makers in unravelling some of the uncertainties inherent in environmental decision making, and these techniques demonstrate a growing interest of previous scholars to apply these techniques for solving different stages of sustainable and renewable energy systems.
Young Tourists and Sustainability. Profiles, Attitudes, and Implications for Destination Strategies
Authors: Buffa Federica
Published: October 2015

Global trends highlight the growing tourist interest in authentic and sustainable holiday experiences. Designing strategies that enable destinations to catch this tourist segment is, therefore, becoming more and more important for competitiveness. A long-term outlook calls into question the “next generation” of actual and potential tourists, i.e., young people: understanding their attitude towards sustainability is paramount to drive tourism development in a direction which is coherent to the forthcoming demand. Drawing from an ad hoc survey of 1156 members of the largest Italian association of student and youth tourism, this contribution (a) discusses youth attitudes towards sustainability, their travel motivations and behavior (b) identifies different profiles of young tourists with reference to sustainability. By using characteristics and dimensions linked with “harder ecotourists” we identify hard path young tourists (HPYT) and soft path young tourists (SPYT). The findings confirm young people’s interest in certain dimensions of sustainability and the influence this interest has on their decision-making processes, motivations, and behaviors. HPYT and SPYT are profiles which should be considered in destination strategies: the strong sensitivity of HPYT to sustainability suggests the possibility of creating offers that optimize the unique features of a territory.
Do Dietary Changes Increase the Propensity of Food Riots? An Exploratory Study of Changing Consumption Patterns and the Inclination to Engage in Food-Related Protests
Authors: Legwegoh Alexander , Fraser Evan , KC Krishna , Antwi-Agyei Philip
Published: October 2015

Following widespread food riots in 2008, many people argued that high food prices cause political instability and civil unrest in the form of food riots. However, subsequent research has demonstrated that political, cultural, and economic factors confound the impact of price in determining whether a food riot occurs. This paper contributes to this growing body of literature by exploring: (1) the relationship between household demographic characteristics and reported intent to riot due to future food price rises; and (2) the relationships between people’s diets and their reported intent to riot due to future food price rises. We hypothesize that local context, including demographic factors and dietary patterns, combine to predispose some groups of people to riot when food prices rise. This hypothesis is tested using household surveys (N = 300) and three focus groups discussions (N = 65) carried out in three cities in the Central African nation of Cameroon that experienced widespread food riots in 2008. Results show that some 70% of the respondents would riot if food prices went up. Also, in the event of food price rises: (1) households in Cameroon’s major cities are more likely to riot than the citizens of smaller cities; (2) Households with relatively higher educational level, high incomes, are less likely to riot. Finally, the relationship between dietary patterns and propensity to riot is not straightforward as changes in consumption of different food groups influence propensity to riot in different ways. Overall, this paper demonstrates that preemptive strategies designed to avoid future food riots in Cameroon must take into consideration these spatial, demographic, and dietary factors.
Quantification of Environmental Flow Requirements to Support Ecosystem Services of Oasis Areas: A Case Study in Tarim Basin, Northwest China
Authors: Xue Jie , Gui Dongwei , Zhao Ying , Lei Jiaqiang , Feng Xinlong , Zeng Fanjiang , Zhou Jie , Mao Donglei
Published: October 2015

Recently, a wide range of quantitative research on the identification of environmental flow requirements (EFRs) has been conducted. However, little focus is given to EFRs to maintain multiple ecosystem services in oasis areas. The present study quantifies the EFRs in oasis areas of Tarim Basin, Xinjiang, Northwest China on the basis of three ecosystem services: (1) maintenance of riverine ecosystem health, (2) assurance of the stability of oasis–desert ecotone and riparian (Tugai) forests, and (3) restoration of oasis–desert ecotone groundwater. The identified consumptive and non-consumptive water requirements are used to quantify and determine the EFRs in Qira oasis by employing the summation and compatibility rules (maximum principle). Results indicate that the annual maximum, medium, and minimum EFRs are 0.752 × 108, 0.619 × 108, and 0.516 × 108 m3, respectively, which account for 58.75%, 48.36%, and 40.29% of the natural river runoff. The months between April and October are identified as the most important periods to maintain the EFRs. Moreover, the water requirement for groundwater restoration of the oasis–desert ecotone accounts for a large proportion, representing 48.27%, 42.32%, and 37.03% of the total EFRs at maximum, medium, and minimum levels, respectively. Therefore, to allocate the integrated EFRs, focus should be placed on the water demand of the desert vegetation’s groundwater restoration, which is crucial for maintaining desert vegetation to prevent sandstorms and soil erosion. This work provides a reference to quantify the EFRs of oasis areas in arid regions.
Optimal Choice of Soil Hydraulic Parameters for Simulating the Unsaturated Flow: A Case Study on the Island of Miyakojima, Japan
Authors: Okamoto Ken , Sakai Kazuhito , Nakamura Shinya , Cho Hiroyuki , Nakandakari Tamotsu , Ootani Shota
Published: October 2015

We examined the influence of input soil hydraulic parameters on HYDRUS-1D simulations of evapotranspiration and volumetric water contents (VWCs) in the unsaturated zone of a sugarcane field on the island of Miyakojima, Japan. We first optimized the parameters for root water uptake and examined the influence of soil hydraulic parameters (water retention curve and hydraulic conductivity) on simulations of evapotranspiration. We then compared VWCs simulated using measured soil hydraulic parameters with those using pedotransfer estimates obtained with the ROSETTA software package. Our results confirm that it is important to always use soil hydraulic parameters based on measured data, if available, when simulating evapotranspiration and unsaturated water flow processes, rather than pedotransfer functions.
Population-Based Estimates of Survival and Cost for Metastatic Melanoma
Authors: McCarron C.E. , Ernst S. , Cao J.Q. , Zaric G.S.
Published: October 2015

Background: Fewer than half of all patients with metastatic melanoma survive more than 1 year. Standard treatments have had little success, but recent therapeutic advances offer the potential for an improved prognosis. In the present study, we used population-based administrative data to establish real-world baseline estimates of survival outcomes and costs against which new treatments can be compared. Methods: Data from administrative databases and patient registries were used to find a cohort of patients with metastatic melanoma in Ontario. To identify individuals most likely to receive new treatments, we focused on patients eligible for second-line treatment. The identified cohort had two characteristics: no surgical resection beyond primary skin excision, and receipt of first-line systemic therapy. Results: Patient characteristics, Kaplan–Meier survival curves, and mean costs are reported. Of the 33,585 patients diagnosed with melanoma in Ontario from 1 January 1991 to 31 December 2010, 278 met the study inclusion criteria. Average age was 63 years, and 62% of the patients were men. Overall survival was estimated to be 19%, 12%, and 6% at 12, 24, and 60 months respectively. Mean survival time was 11.5 months, and mean cost was $30,685. Conclusions: Our baseline estimates indicate that survival outcomes are poor and costs are high for patients receiving standard treatment. Understanding the relative improvement accruing from any new treatment requires a comparison with the existing standard of care.
Pleural Fluid Tumour Markers in Malignant Pleural Effusion with Inconclusive Cytologic Results
Authors: Antonangelo L. , Sales R.K. , Corá A.P. , Acencio M.M.P. , Teixeira L.R. , Vargas F.S.
Published: October 2015

Background: The presence of tumour cells in pleural fluid or tissue defines an effusion as malignant. Cytology analysis of the pleural fluid has about 60% diagnostic sensitivity. Several tests have been proposed to improve diagnosis—among them, the concentrations of tumour markers in pleural fluid. We evaluated whether the concentrations of tumour markers in pleural fluid could improve the diagnosis of malignant pleural effusion (mpe) when cytology is doubtful. Methods: Lymphocytic pleural fluids secondary to tuberculosis or malignancy from 156 outpatients were submitted for cytology and tumour marker quantification [carcinoembryonic antigen (cea), cancer antigen 15-3 (ca15-3), carbohydrate antigen 19-9 (ca19-9), cancer antigen 72-4 (ca72-4), cancer antigen 125 (ca125), and cyfra 21-1). Oneway analysis of variance, the Student t-test or Mann–Whitney test, and receiver operating characteristic curves were used in the statistical analysis. Results: Concentrations of the tumour markers cea, ca15-3, ca125, and cyfra 21-1 were higher in mpes than they were in the benign effusions (p < 0.001), regardless of cytology results. The markers ca19-9 and ca72-4 did not discriminate malignant from benign effusions. When comparing the concentrations of tumour markers in mpes having positive, suspicious, or negative cytology with concentrations in benign effusions, we observed higher levels of cea, ca15-3, cyfra 21-1, and ca125 in malignant effusions with positive cytology (p = 0.003, p = 0.001, p = 0.002, and p = 0.001 respectively). In pleural fluid, only ca125 was higher in mpes with suspicious or negative cytology (p = 0.001) than in benign effusions. Conclusions: Given high specificity and a sensitivity of about 60%, the concentrations of tumour markers in pleural effusions could be evaluated in cases of inconclusive cytology in patients with a high pre-test chance of malignancy or a history of cancer.
Stereotactic Ablative Radiotherapy with CyberKnife for Advanced Thymic Carcinoma: A Case Report
Authors: Fan C.Y. , Huang W.Y. , Jen Y.M. , Lin M.J. , Lin K.T.
Published: October 2015

Thymic carcinoma is a rare but lethal mediastinal cancer. The optimal treatment for advanced thymic carcinoma is not yet established. This report is the first known of stereotactic ablative radiotherapy (sabr) with CyberKnife (Accuray, Sunnyvale, CA, U.S.A.) as definitive therapy for thymic carcinoma. The patient, a 70-year-old woman with thymic carcinoma, invasion into neighboring organs, and pleural metastases—underwent CyberKnife sabr at 40 Gy in 5 fractions for two lesions, one in the thymus and one in the right paraspinal pleura. After 61 months of observation, a partial response was observed in the irradiated fields. However, disease progression in the non-irradiated pleura was noted. The patient underwent salvage CyberKnife sabr for the four initially nonirradiated pleural lesions. Computed tomography images obtained 10 months after the salvage therapy revealed a partial response. The patient is living, with progression-free irradiated lesions and no radiation-related toxicity. CyberKnife sabr is feasible for patients who are unable to undergo either surgery or conventionally fractionated radiation therapy.
Traumatismes et fuite dans la rue
Authors: Bernichi Asmaa
Published: October 2015

A Casablanca, comme partout dans le monde, des enfants et des adolescents vivent dans les rues des grandes métropoles. Vulnérables, marginalisés, clochardisés et toxicodépendants, ceux que nous avons rencontrés nous ont livré les récits de leurs trajectoires de vie et de rue. Cet article propose d’interroger ce moment de passage dans la rue en articulation avec les traumatismes d’enfance. Nous verrons comment ces enfants et ces adolescents de la rue fuient un environnement familial défaillant et des traumatismes vécus au sein de leur famille. Cette fuite signe leur rupture avec l’environnement familial et leur inscription dans l’errance. Ainsi, ils se retrouvent enfermés dehors aux prises avec la survie au quotidien et des traumatismes non élaborés.
Désir et responsabilité au féminin afro-brésilien
Authors: Leal de Barros Mariana , Henriques Bairrão José Francisco Miguel
Published: October 2015

La pombagira est un esprit féminin de l’umbanda (religion afro-brésilienne) associé aux images des féminins subversifs et incorporé généralement par des femmes en transe de possession. Sur la base d’une recherche ethnographique dans l’ umbanda de São Paulo et par le biais d’une analyse ethno-psychanalytique, nous étudions comment la pombagira permet au sujet d’élaborer son désir, ce qu’on articule comme expression de sa féminité.
Collaborer pour faire le bien
Authors: d’Amours Liette , Ferland Mathieu , Jacob Réal , Poitras Jean
Published: October 2015

Dix-huit mois : c’est le temps qu’il aura fallu à Ubisoft, à une équipe de recherche médicale de l’Université McGill et à leur partenaire américain pour réaliser une percée technologique, thérapeutique et bientôt commerciale. Comment expliquer ce rapprochement et, surtout, en expliquer la réussite ? Mathieu Ferland, producteur de jeux chez Ubisoft, suivi de Réal Jacob et de Jean Poitras, de HEC Montréal, nous exposent les apprentissages tirés de cette expérience. Et si une productivité et une capacité d’innovation accrues passaient par une telle collaboration intersectorielle ?
L’économie circulaire
Authors: Lanoie Paul , Normandin Daniel
Published: October 2015

Depuis quelques années, le concept d’économie circulaire tend à se confirmer. Ce modèle économique émergent, qui vise essentiellement à maximiser les ressources déjà en circulation et à réduire l’empreinte écologique, déclasse l’économie linéaire, visiblement sur le déclin. Bien qu’encore méconnu, il repose entre autres sur l’écoconception, accroît manifestement la rentabilité et fidélise la clientèle. Outre le fait qu’il s’avère avantageux pour tous, ce mode de production permettra à l’entreprise du dirigeant qui y croit de se distinguer dans un marché où la volatilité du prix des ressources occasionne une tension constante. Déjà, en Asie et en Europe, l’économie circulaire, pressée par des défis environnementaux et sociaux en plus d’être stimulée par la réglementation, connaît une grande effervescence. Chez nous comme ailleurs, elle incarne un modèle d’affaires grâce auquel la créativité permet de dépasser les horizons explorés.
Neonatal and Prepubertal Gynecologic Concerns
Authors: Merens Teri A.
Published: October 2015

The role of the pediatrician in today’s health care environment is one of constant evolution, as specialty care becomes more difficult to access for a growing number of young patients and their families. The primary care doctor will now have to offer more reassurance and follow-up that was once thought to be solely the role of the subspecialist. This article helps to define commonly seen entities in pediatric gynecology and offers the necessary background enabling the practitioner to provide a simple course of treatment, reassurance, or appropriate referral for specialty care.
[Pediatr Ann. 2015;44(10):412,414,416–417.]
Automatic Fish Segmentation and Recognition for Trawl-Based Cameras
Authors: Chuang Meng-Che , Hwang Jenq-Neng , Williams Kresimir
Published: October 2015

Camera-based fish abundance estimation with the aid of visual analysis techniques has drawn increasing attention. Live fish segmentation and recognition in open aquatic habitats, however, suffers from fast light attenuation, ubiquitous noise and non-lateral views of fish. In this chapter, an automatic live fish segmentation and recognition framework for trawl-based cameras is proposed. To mitigate the illumination issues, double local thresholding method is integrated with histogram backprojection to produce an accurate shape of fish segmentation. For recognition, a hierarchical partial classification is learned so that the coarse-to-fine categorization stops at any level where ambiguity exists. Attributes from important fish anatomical parts are focused to generate discriminative feature descriptors. Experiments on mid-water image sets show that the proposed framework achieves up to 93% of accuracy on live fish recognition based on automatic and robust segmentation results.
A Survey on Islamic Mobile Applications for Children
Authors: Machfud Fitria Maulida , Mahmud Murni
Published: October 2015

This paper investigates Islamic mobile applications for children and evaluates the quantity as well as the quality of such applications. The existing and new criteria for exploring Islamic mobile applications used in this study have been enhanced and extended from the level of quality assessment to a deeper aspect of Islamic mobile application's design and interface. Similarly, additional aspects have also been considered to analyse whether it is suitable for children in terms of language, examples used, and whether it is in accordance to the Islamic foundation of Shari'ah that relies on primary and secondary sources of knowledge, which are: Qur'an, Sunnah, and Fiqh Science. The finding shows that there are very few of Islamic apps for children, especially in Malay and Indonesian language. This study suggests that developers should design and develop more Islamic mobile apps for children, especially with education and entertainment features. This study also recommends some requirements and guidelines in designing Islamic apps that are suitable for Muslim children.
Digital Competence
Authors: Avni Edith , Rotem Abraham
Published: October 2015

This chapter presents a proposal for a conceptual framework of digital competence, which is a civil right and need and is vital for appropriate, intelligent study and functioning in the real world, through means that technology and the internet offer the citizen. Digital competence in the 2010s is a multifaceted complex of a net of literacies that have been updated, reformulated and transformed under the influence of technology. The framework of the digital competency includes eight fields of digital literacies. At the top of the net is digital ethics literacy, outlines the moral core for proper use of technology; at the base are technological literacy and digital reading and writing literacy, comprising the foundation and interface for all the digital literacies, and in between are the digital literacies in these fields: information literacy, digital visual literacy, new media literacy, communication and collaboration literacy and social media literacy. These interconnected literacies compose a synergetic complex of the digital competence framework.
Advances in Automated Scoring of Writing for Performance Assessment
Authors: Foltz Peter W.
Published: October 2015

The ability to convey information through writing is a central component of real-world skills. However, assessing writing can be time consuming, limiting the timeliness of feedback. Automated scoring of writing has been shown to be effective across a number of applications. This chapter focuses on how automated scoring of writing has been extended to assessing and training of real-world skills in a range of content domains. It illustrates examples of how the technology is used and considerations for its implementation. The examples include 1) Formative feedback on writing quality, 2) scoring of content in student writing. 3) improving reading comprehension through summary writing, and 4) assessment of writing integrated in higher-level performance tasks in professional domains.
China's Growing Meat Demands
Authors: Guo Xiumei , Raphaely Talia , Marinova Dora
Published: October 2015

The chapter examines China's growing meat demand and its implications. Australia and China are currently set to expand trade in meat and livestock facilitated by a government negotiated Free Trade Agreement. China is already the world's largest meat consumer and with the increasing consumerism and wealth of its rapidly growing middle and upper class, the demand for animal products is likely to grow. This country's unprecedented appetite for animal proteins has stimulated the Australian livestock and related sectors, potentially enabling vast growth and profitability within these industries. Chinese customers have strong purchasing power and are eager to buy imported frozen and locally slaughtered Australian meat. While Australian farmers are capitalising on these economic opportunities, only the animal welfare sector voices any concern. This chapter highlights the ignored health and environmental costs.
Study of Calcium Magnesium Aluminate CaMgAl10O17 Formation
Authors: Gavrilenko Ekaterina A. , Kuznetsova Ekaterina E. , Selyunina Liliya A. , Mishenina Lyudmila N.
Published: October 2015

Aluminates of alkaline earth elements have high photoluminescence properties and resistance to UV radiation. Due to this, they are widely used in optical industry. In this work magnesium calcium aluminate was prepared by sol-gel method. The main stages of the formation of the crystalline structure CaMgAl10O17 were determined by thermal analysis, X-ray diffraction and IR spectroscopy. The surface morphology was studied using scanning electron microscopy. The ratio of elements in the product was installed by X-ray microanalysis.
Investigation of Intermediate Oxidation Products of Genistein and Luteolin Generated in Aerobic Conditions
Authors: Khasanov Victor , Kravtsova Svetlana , Dychko Konstantin , Khasanov Vyacheslav
Published: October 2015

Unstable intermediate oxidation products in the solution of Luteolin [L] and Genistein [G] were discovered by HPLC-MS-ESI(-) in aerobic conditions at pH=8. These covalently bonded compounds of [2L-H2] and [L+G-H2] compositions, as well as trimeric [L+2G-2H2], can be separated by the HPLC, but easily undergo further destruction. Possibly, such compounds are products of initial radical oxygenation. In trimeric conjugate Luteolin, as a more potent reducing agent, binds two Genistein molecules together.
Structural and Mechanical Properties of Highly Paraffinic Crude Oil Processed in High-Frequency Acoustic Field
Authors: Volkova Galina I. , Anufriev Roman V.
Published: October 2015

Methods of chromatography-mass spectrometry, IR spectroscopy, viscometry were used to study structural and mechanical properties of highly paraffinic crude oil processed in high-frequency acoustic field. It was shown that ultrasonic treatment leads to an increase in viscosity, yield stress, viscous flow activation energy and internal fracture energy of dispersion system with an increase in processing time. Proportion of n-alkanes С15Н32–С16Н34 and concentration of aromatic hydrocarbons increase in the composition of dispersed phase of processed crude oil according to chromatography-mass spectrometry.
Extraction of a Dynamic Multiport Compact Thermal Model for a Silicon Microthruster
Authors: Salleras M. , Palacin J. , García I. , Puig M. , Samitier J. , Marco S.
Published: October 2015

In this work, a methodology to extract dynamic multiport compact thermal model from finite element model (FEM) thermal simulations is presented. The proposed methodology is applied to an innovative silicon microthruster. The boundary conditions of the FEM model have been estimated from experimental measurements. The analysis of these transients with the methodology presented delivers a dynamic multiport compact RC model representation of the complete structure. The topology and sizing of the components is provided by a hybrid combination of Sequential Search algorithms together with nonlinear least squares optimization.
An Approach To Numerical Simulation Of Thermal Contact Problems In Modern Electronic Packages
Authors: Friedel K. , Wymyslowski A.
Published: October 2015

The increasing demand on higher packaging density, higher frequency and higher power of the electronic devices is a challenge for contemporary engineers to be able to simulate and prototype as mechanical as thermal problems. The heat dissipation problem is becoming nowadays a crucial issue and requires application of materials with high thermal conductivity and novel packaging methods. Currently there are a number of recognised “bottle necks” for heat dissipation in electronic packages. One of them is a thermal contact resistance (TCR), which arises in the region where two solid contact members touch each other. The high TCR reduces the amount of heat which can be transmitted from the heat source to the heat sink and the same raises the device temperature and reduces the overall reliability of the package due to thermo-mechanical stresses.

There have been a large number of theoretical and experimental investigations performed to understand and improve the knowledge on TCR. The TCR arises in the region of contact, when two solids are pressed together. The real contact area is only a small fraction of the nominal or apparent area [1]. Despite of the profound studies not fully understanding and satisfactory method has been elaborated to be able to predict with reasonable accuracy the heat conduction across the contact. Besides, the thermal properties of TCR are not known and only some assumptions are made to be able to simulate the temperature distribution over electronic packages with the TCR existence.

In this paper a combined experimental-numerical approach to the simulation of thermal contact problems in electronic package is applied. The test results revel that the approach can be a promising solution allowing for quick verification and evaluation of temperature distribution in high power electronic packages, which seem to be crucial nowadays.
Board Level Reliability Enhancement for A Double-bump Wafer Level Chip Scale Package
Authors: Zhang Xiaowu , Wong E. H. , Iyer Mahadevan K.
Published: October 2015

This paper presents a nonlinear finite element analysis on board level solder joint reliability enhancement of a double-bump wafer level chip scale package (CSP). A viscoplastic constitutive relation is adopted for the solders to account for its time and temperature dependence in thermal cycling. The fatigue life of solder joint is estimated by the modified Coffin-Manson equation, which has been verified by experimental results using one of the double-bump wafer level CSP packages as the test vehicle. A series of parametric studies were performed by changing the Sn/Ag inner bump size (UBM pad size and standoff height), the eutectic Sn/Pb external solder joint size (pad size and standoff height), pitch, die thickness, and the encapsulant thickness. The results obtained from the modeling are useful to form design guidelines for board level reliability enhancement of the wafer level CSP packages.
Investigation of Steady State and Transient Thermal Management in Portable Telecommunication Product – Part 2
Authors: Yee Cheang Soon , Quadir G.A. , Zainal Z.A. , Seetharamu K.N.
Published: October 2015

In Part 2 of this paper, transient thermal management in portable telecommunication product using phase change material (PCM) was numerically investigated. The thermal time-dependent simulation methodology using non-linear transient finite element analysis (FEA) on a solid conduction cellular phone model cooled by natural convection and radiation was verified experimentally. For the phase change problem itself, a pure conduction PCM model with enthalpy changes was utilized. The effect of convection heat transfer in liquid phase is enhanced thermal conductivity. The numerical methodology used by Hodes et al. [3] and Lamberg et al. [13] was verified with both package and system level experimental results. With the confidence gained from the verification work using this simulation methodology, further parametric study was carried out. In this paper, the effect of PCM volume, aspect ratio of the container and amount of heat dissipated are examined. The advantages gained from its recovery period and introduction of thermal conductivity enhancement are also discussed.
Pretreatment of Blind Via Holes before Ni/Au and Cu Plating Applied with Atmospheric Pressure Plasma Jet
Authors: Sawada Yasushi , Yamazaki Keiichi , Taguchi Noriyuki , Shibata Tetsuji
Published: October 2015

The effectiveness of atmospheric pressure (AP) plasma preprocessing before Ni/Au or Cu plating has been examined by applying it to a build-up printed circuit board (FR-4 grade) and polyimide-based flexible circuit film, both with blind via-holes (BVHs). The AP plasma applied with a dielectric barrier discharge is generated inside a 56 mm wide quartz vessel by an RF power generator using Ar-O2 gas mixture. One side of the vessel is open and the plasma jet is blown on the sample substrate transported 5 mm downward from the outlet of the vessel. The deposit failure rate of Ni/Au electroless deposit to 50 μm-diameter BVHs formed on a photo resist on the printed circuit board is 12.5% without preprocessing but is decreased to 0% after applying the AP plasma processing. As for 50 μm-diameter BVHs formed with a YAG laser on a polyimide-based flexible circuit film, the bump formation using electrolytic copper plating fails without preprocessing, but a 100% bump formation rate is achieved after applying AP plasma processing. It is presumed that the AP plasma processing improves the wetting property of the BVH walls and allows the plating solution to uniformly cover the entire wall surfaces without generating bubbles. The removal of organic substances attached to the BVH bottom surface also helps to improve the adherence of metal plating.
Micromachined Vibration Isolation Filters to Enhance Packaging for Mechanically Harsh Environments
Authors: Dean Robert , Flowers George , Sanders Nicole , Horvath Roland , Kranz Michael , Whitley Michael
Published: October 2015

Some harsh environments, such as those encountered by missiles, rockets and various types of industrial machinery, contain high frequency mechanical vibrations. Unfortunately, some very useful components are sensitive to these high frequency vibrations. Examples include MEMS gyroscopes, oscillators and some micro-optics. Exposure to high frequency mechanical vibrations present in the operating environment can result in problems ranging from an increased noise floor to component failure. Passive micromachined silicon lowpass filter structures (spring-mass-damper) have been demonstrated in recent years. Since they usually possess a low vertical profile, they can be utilized as the packaging substrate for the sensitive component requiring vibration isolation. The performance of these filter structures is typically limited by low damping and a lack of tunability after fabrication. However, filter performance can be enhanced by integrating fluidic damping techniques with the passive filter or by integrating a micromachined actuator with state feedback to realize an active filter. The active filter has the additional advantage of post fabrication tunability.
Experimental Evaluation of Glob-top Materials for use in Harsh Environments
Authors: Lindgren Mats , Belov Ilja , Leisner Peter
Published: October 2015

This article presents results of experimental evaluation of glob-top materials for multi-chip-modules (MCM) in harsh environments. Material and process tests have been performed with the purpose to find a material which would fulfill the reliability requirements for use e.g. in military or automotive applications. Seven polymer materials, i.e. four epoxies, two silicones and one polyurethane material have been selected and evaluated in the experiments. The most critical material and process parameters for glob-top have been identified and measured. Based on the experimental results, application-based scoring of studied epoxy materials has been performed. Material evaluation results have been summarized in conclusions about the most suitable glob-top material for use in harsh environments.
Effects of gold on the properties of tin-antimony solder in flip-chip-pin-grid-array (FCGPA) packages
Authors: Kee See Bee , Hussain Luay B , Nair Kesavan , Khong YL , Kumar Dennis Chandran Prem
Published: October 2015

The physical characteristics of tin-antimony solder used in FCPGA semiconductor packages change with the diffusion of gold from the gold plated layers in the solder pads or pin. This must be considered in the setting of parameters for subsequent re-flow processes and also possible impact on the quality and reliability of the solder joints. This paper describes physical and micro-structural properties of the 95Sn5Sb parent material alloyed with 1, 2, 2.5, 3, 3.5, 4 and 5 wt% of gold. In particular, the paper documents the decrease in the solidus and liquidus temperatures, increase in the Brinell hardness, and increase in both the electrical and thermal conductivity of 95Sn5Sb solder doped with gold.
New Analytical Model for the Dielectric Loss of Microstrip Lines on Multilayer Dielectric Substrates: Effect of Conductor-Dielectric Interphase
Authors: Vo Hung T. , Shi Frank G.
Published: October 2015

The existing CAD formulae for dielectric loss of microstrip lines on substrate are complicated and inaccurate at high frequencies. In particular, no closed-form expression has been obtained for the dielectric loss of microstrip lines on multi-layer dielectric substrate by including the conductor-substrate interphase effect, although attempts have been made to study the finite thickness effect of the conductor and dielectric substrate. The present work represents the first attempt to obtain a closed-form CAD formula for the dielectric loss of microstrip lines on dielectric substrates by considering the effect of conductor-substrate interphase. Our simple and accurate model systematically considers the effect of the interphase between the microstrip line and substrate by using a quasi-TEM approach and is shown to be supported by the available experimental data.
Analysis of Embedded Baluns in 3D Packages
Authors: Mäntysalo Matti , Heino Pekka
Published: October 2015

The requirements for electronic packaging are continually increasing, since the trend is towards more personal and highly integrated products. The demands for electronic packaging are lower cost, lighter weight, lower power consumption, and higher integration rate. These requirements can be addressed with System-in-Package (SiP) technologies, which is a powerful concept for system integration. SiP, together with embedded passives, provides an attractive option to solve future packaging challenges. It has a huge potential especially with small portable electronics, such as, wireless headsets and portable terminals. This paper describes the design of embedded stripline baluns for 2.4 GHz low-range radio applications. We will discuss the design, implementation, and layout of three-dimensional baluns. The effect of a balun's layout was studied with a three-dimensional electromagnetic simulator, which is based on the finite-integration technique. Good impedance match and excellent amplitude and phase balances between output ports were achieved. In addition, several prototypes were also manufactured and measured. The correlation between the simulation and experimental results was excellent. The error between modeled and measured center frequencies was less than three percent.
A Novel Scheme for Wide Bandwidth Chip-to-Chip Communications
Authors: Liu Qing , Fay Patrick , Bernstein Gary H.
Published: October 2015

Quilt Packaging (QP), a novel chip-to-chip communication paradigm for system-in-package integration, is presented. By forming protruding metal nodules along the edges of the chips and interconnecting integrated circuits (ICs) through them, QP offers an approach to ameliorate the I/O speed bottleneck. A fabrication process that includes deep reactive ion etching, electroplating, and chemical-mechanical polishing is demonstrated. As a low-temperature process, it can be easily integrated into a standard IC fabrication process. Three-dimensional electromagnetic simulations of coplanar waveguide QP structures have been performed, and geometries intended to improve impedance matching at the interface between the on-chip interconnects and the chip-to-chip nodule structures were evaluated. Test chips with 100 μm wide nodules were fabricated on silicon substrates, and s-parameters of chip-to-chip interconnects were measured. The insertion loss of the chip-to-chip interconnects was as low as 0.2 dB at 40 GHz. Simulations of 20 μm wide QP structures suggest that the bandwidth of the inter-chip nodules is expected to be above 200 GHz.
Suppression of SSN by Embedded Decoupling Capacitor in LTCC Package
Authors: Park Yun-Hwi , Oh Kwangje , Kim Ikseop , Chu Hosung , Sung Jehong , Yun Seokchul , Kim Jinwaun
Published: October 2015

In this paper, the authors present the noise suppression performance using a decoupling capacitor which is embedded in an LTCC substrate. To embed high value capacitors (>20nF), a high K (over 500) material which can be co-fired with low K LTCC was developed successfully. Thin high K sheets under 10μm were co-laminated between low K sheets, which form the power and ground planes. Due to the short distance from the IC power pin to the decoupling capacitor, the ESL (Equivalent Series Inductance) is much lower than with surface mounted type capacitors, and so, SSN (Simultaneous Switching Noise) can be reduced significantly. To verify the noise suppression performance, we designed and fabricated a digital module using 100MHz CPLD (Complex Programmable Logic Device) on top of the LTCC substrate in which a 25nF decoupling capacitor was embedded. By measurement, we can see that SSN of CPLD on LTCC was reduced by 80% compared with designs that use surface mounted type 100nF capacitors. This embedded decoupling capacitor in LTCC (LEDC) can be useful for digital SiP (System In Package) to enhance noise performance and to reduce its footprint.
A Real-Time Precision Characterization Technique for Low-Loss Optical Polymeric Waveguide and Lightwave Circuits
Authors: Wang Fengtao , Liu Fuhan , Chang Gee-Kung , Yao Mathew Q. , Adibi Ali , Tummala Rao
Published: October 2015

An optical polymer waveguide is a key passive component for the optical interconnection. Design, fabrication, and characterization of high-performance waveguides have critical importance for the success of optoelectronic integration. In addition, defect effects, coupling, leakages, crosstalk, etc. are great concerns for the lightwave circuits. We present herein a fast, nondestructive, sensitive, real-time technique for detailed investigation of the propagation properties of planar optical waveguides and lightwave circuits. We use this technique to measure low-loss polymer waveguides on printed circuit board (PCB) substrates, and we have measured propagation losses of 0.065 dB/cm at 850 nm and 0.046 dB/cm at 980 nm. To the best of our knowledge, these are among the lowest losses reported to date for polymer waveguides on PCB substrates. A high-sensitivity CCD camera with a built-in integration function is utilized to observe the light streak in two dimensions through a two-lens imaging system. A few seconds to a few tens of seconds is needed for one complete measurement, compared with the sliding prism method, which requires several hours, and the cutback method, which requires even longer times. This technique can be used to evaluate not only the overall performance of a waveguide but also the local waveguide performance, as well as perform in-situ investigation of propagation properties (defect effect, bending effect, coupling, leakage, etc.). It can be extended to monitor the process of waveguide fabrication and alignment control during assembly for lightwave circuit integration.
Heatsink Mass Optimization Methodology for Desktop Microprocessor Cooling
Authors: Merrikh Ali A. , Eyman Mike , Walshak David B. , Dolbear Tom , Sundaram Sridhar
Published: October 2015

We present a novel modeling methodology for optimizing the mass of aluminum-extruded heatsinks for cooling desk-top microprocessors. The two-stage study aims at reducing mass of an aluminum-extrusion heatsink by taking advantage of the existing thermal resistance margin. In Stage 1, we investigated several possible combinations of base shapes to minimize the mass of the base region. Base shape is optimized by dividing the base volume into several blocks of equal width, with the objective of progressively minimizing the mass of the peripheral region while shaping the middle region to minimize spreading resistance. Three base shape profiles—namely, wedge, semielliptical, and flat top—were selected for further study. In Stage 2, a thorough base, fin thickness, and fin count study was carried out by mathematical optimization. The result of this optimization exercise was a 30% reduction in the heatsink mass. The degradation in thermal resistance of the mass-reduced design is within the acceptable margin and meets microprocessor product specifications. Results are experimentally verified by testing four different competing samples having comparable optimized masses.
Transforming a Laser Micromachiner into a Direct-Write Tool for Electronic Materials
Authors: Halvorsen Aaron D. , Vaidya Pooja , Robinson Matthew , Schulz Douglas L.
Published: October 2015

A conventional laser micromachining system is configured for use as a matrix-assisted pulsed laser evaporation direct-write (MAPLE-DW) system in a straightforward and cost-effective manner. The simplicity of the method is illustrated by highlighting the process for MAPLE-DW of polymer composites used in chemical gas sensor arrays. Important aspects are considered, including ribbon preparation, ribbon aging, and computerized process control for rapid prototyping.
LTCC-Modules with Integrated Ferrite Layers—Strategies for Material Development and Co-Sintering
Authors: Glitzky Carsten , Rabe Torsten , Eberstein Markus , Schiller Wolfgang A. , Töpfer Jörg , Barth Stefan , Kipka Annette
Published: October 2015

The integration of passive components (resistors, capacitors, inductors) into LTCC modules is a challenging task in multilayer ceramics technology. We report on multilayer assemblies consisting of combined layers of ferrite and dielectric LTCC tapes. Ni-Cu-Zn ferrites with maximum shrinkage at 900°C were processed to green tapes and laminated with dielectric LTCC tapes. Cosintering at 900°C led to multilayers with different defects such as incomplete densification of the ferrite layers, cracks, and warpage. Since ferrite tapes do not really allow compositional changes without deterioration of magnetic properties, the dielectric tape was modified with the following objectives: (i) matching of the shrinkage curves of dielectric and ferrite materials, (ii) adjusting the coefficients of thermal expansion to avoid cracking during cooling, and (iii) controlling of interface reactions. Using this concept we fabricated dense and defect-free multilayers consisting of dielectric and ferrite layers. However, compositional changes of the individual ferrite tapes require the development of a specific dielectric tape material with tailored properties.
Reliability Assessment and Failure Analysis of G-Helix, a Free-Standing Compliant Off-Chip Interconnect
Authors: Kacker Karan , Sitaraman Suresh K.
Published: October 2015

Continued miniaturization in the microelectronics industry calls for chip-to-substrate off-chip interconnects that have 100 μm pitch or less for area-array format. Such fine-pitch interconnects will have a shorter standoff height and a smaller cross-section area, and thus could fail through thermo-mechanical fatigue prematurely. Also, as the industry transitions to porous low-K dielectric/Cu interconnect structures, it is important to ensure that the stresses induced by the off-chip interconnects and the package configuration do not crack or delaminate the low-K dielectric material. Compliant free-standing structures used as off-chip interconnects are a potential solution to address these reliability concerns. In our previous work we have proposed G-Helix interconnects, a lithography-based electroplated compliant off-chip interconnect that can be fabricated at the wafer level. In this paper we develop an assembly process for G-Helix interconnects at a 100 μm pitch, identifying the critical factors that impact the assembly yield of such free-standing compliant interconnect. Reliability data are presented for a 20 mm × 20 mm chip with G-Helix interconnects at a 100 μm pitch assembled on an organic substrate and subjected to accelerated thermal cycling. Subsequent failure analysis of the assembly is performed and limited correlation is shown with failure location predicted by finite elements models.
Mixed LTCC and LTTT Technology for Microplasma Generator Fabrication
Authors: Yamamoto Roberto K. , Gongora-Rubio Mário R. , Pessoa Rodrigo S. , Cunha Márcio R. , Maciel Homero S.
Published: October 2015

An issue of paramount importance for the fabrication of microplasma devices is internal structure flatness. To overcome this problem we devised a fabrication method using LTCC (Low Temperature Cofired Ceramic) and LTTT (Low Temperature Transfer Tape) technologies. The flexibility resulting from mixing these technologies could enable fabrication of certain microfluidic applications. In the present work, the fabrication of a microplasma generator using a mixed LTCC and LTTT technology is presented. Silver-palladium electrodes were screen printed on the green tapes and were cofired after machining of microchannels and other structures. Two electrode plates were obtained separately in this way using a setter powder sheet to ensure flatness. In the postfire process, transfer tapes were used to bind the two electrode plates and the electrode spacer together to make the final device structure. Uniform and stable glow discharges were obtained in argon, nitrogen, oxygen, and sulfur hexafluoride gases. Paschen's curves, V-I characteristics, and optical emission spectra were obtained in DC discharges. The fabrication method presented has been demonstrated to be very reproducible and produced very flat electrodes.