bluuebunny/crossref_metadata_2025 huggingface dataset:
PENGEMBANGAN MEDIA PEMBELAJARAN MENGGUNAKAN GEOGEBRA PADA SUB POKOK BAHASAN GARIS SINGGUNG PERSEKUTUAN DUA LINGKARAN
Authors: Rohmawati Elok , Kristanto Vigih Hery
Published: February 2019

This research is a development research that aims to to find out the process and result of development of learning media of mathematics using Geogebra on sub subject of tangent alliance of two circles. Supporting devices used are RPP, BKS, BPG, and THB. The chosen development stage is Research and Development (R & D) which has been modified by adding Nieveen criteria that is valid, practical and effective. Data collection techniques used questionnaires, observation sheets and tests. According to the criteria of practicality, it is known that the questionnaire of ease of using media reaches 79.8%. The operation of this media is so easy that it's easy to remember and can be used as a tool to learn the material. Questionnaires the role of teachers reached 81%. By using the teacher's activity media in explaining the material to be a little, because the students are more observing, summing up opinions, and working on the problem, so the teacher's interaction with the students is minimal, and the material explanation is enough to use the media. Observation sheet minimizes teacher's role by 76.95%. From the observer observation the students observed more, no difficulties in the use of media. However, learning cannot be finished as in RPP. According to the effectiveness criteria seen from the test of student learning outcomes so that the mastery of classical reach 35%. This is because learning is too focused on observation and discovery of the formula so that students do not practice in doing the problem. From this research, there are several findings, namely: learning media using Geogebra, supporting tool, namely RPP, BKS, BPG, THB and instrument have validity level on valid criteria, learning media using Geogebra is easy to use, learning media using Geogebra with supporting device can minimize the role of teachers so that the media meet the practical criteria. The test of learning outcomes has not been completed in a classical manner because the classical completeness does not reach 75% upwards, meaning that the media has not met the effective criteria.
EFEKTIVITAS PENGGUNAAN MEDIA PEMBELAJARAN BERBASIS VIDEO TERHADAP PEMAHAMAN KONSEP MATEMATIS SISWA
Authors: Gusmania Yesi , Dari Tri Wulan
Published: February 2019

Abstrak: Penelitian ini bertujuan untuk mengetahui: (1) terdapat perbedaan efektivitas dalam penggunaan  media pembelajaran dengan berbasis video dan tidak menggunakan media pada pembelajaran konvensional terhadap pemahaman konsep matematis siswa. Jenis penelitian ini adalah penelitian eksperimen semu dengan desain penelitian Control Group Pretest- Posttest. Populasi penelitian ini adalah seluruh siswa SMPN 20 Batam kelas VIII tahun pelajaran 2016/2017. Pengambilan sampel dilakukan dengan teknik Cluster Random Sampling. Sampel penelitian kelas eksperimen VIII.4 dan sampel kelas kontrol VIII.2. Analisis data menggunakan rumus uji t dua sampel. Sebelum data dianalisis, data terlebih dahulu diuji prasyarat analisis yaitu uji normalitas dan homogenitas. Kemudian dilakukan uji hipotesis berdasarkan data tersebut. Hasil penelitian menunjukan bahwa: (1) terdapat efektivitas antara pembelajaran dengan media pembelajaran berbasis video dengan pembelajaran konvensional yang ditinjau dari pemahaman konsep matematis siswa. Kata Kunci : media video pembelajaran, metode konvensional, pemahaman konsep matematis Abstract:This research aims to know: (1) whether there are effectiveness and the difference between using video based learning media and not using media with conventional learning reviewed from student mathematical concepts understanding. The kinds of this research is Quasi Experiments research with Control Group Pretest Posttest research design. The population of this research are all student at SMPN 20 Batam in class VIII academic years 2016/2017. Taking sampling was done by Cluster Random Sampling technique. The research sample of experiment class is VIII.4 and sample of control class is VIII.2. The data was analyzed with using t test two sampling. Before the data was analyzed, the data was first tested on the pre requisite of analysis, there are normality test and homogeneity test. Then, conducted hypothesis test based on the data. The result of this research showed that: (1) there was the difference between video based learning media with conventional learning toward student mathematical concepts understanding. Key Words : VBL, conventional methods, mathematical concepts understanding.
PENGEMBANGAN MODUL SISTEM PERTIDAKSAMAAN DUA VARIABEL BERBASIS GEOGEBRA TERHADAP KEMAMPUAN VISUAL THINKING MATEMATIS SISWA KELAS X
Authors: Himmi Nailul , Hatwin Lia Bidari Agustin
Published: February 2019

Abstrak. Penelitian pengembangan ini bertujuan untuk membuat bahan ajar matematika berupa modul pada materi sistem pertidaksamaan dua variabel berbasis GeoGebra terhadap kemampuan visual thinking matematis siswa SMA kelas X, serta mengetahui kualitas bahan ajar ditinjau dari kevalidan, kepraktisan, dan keefektifan. Pengembangan modul dilakukan berdasarkan model ADDIE dengan tahapan analisis, desain, development, implementation, dan evaluation. Instrumen yang digunakan berupa lembar penilaian modul untuk ahli materi dan ahli media untuk mengukur kevalidan, angket respon siswa untuk mengukur kepraktisan, serta soal tes visual thinking untuk mengukur keefektifan media. Uji coba produk dilakukan sebanyak 3 kali di SMA Negeri 8 Batam pada kelas X MIPA 5 yang mengimplementasikan Kurikulum 2013. Hasil penelitian ini berupa modul sistem pertidaksamaan dua variabel berbasis GeoGebra terhadap kemampuan visual thinking matematis siswa SMA kelas X. Berdasarkan hasil penelitian diperoleh bahwa modul dikatakan sangat valid (3,46), praktis (3,04) dan efektif (89%), serta kemampuan visual thinking matematis siswa dengan rata-rata kelas 89,61.
Kata Kunci: Modul, visual thinking, dan Geogebra
Abstract. This development research aims to create mathematics teaching materials in the form of modules on the material of the system of inequality of two variables based on GeoGebra on mathematical visual thinking ability of high school students of class X, and to know the quality of teaching materials in terms of validity, practicality and effectiveness. The module development is based on the ADDIE model with the stages of analysis, design, development, implementation, and evaluation. Instruments used in the form of a module assessment sheet for material experts and media experts to measure validity, questionnaire responses to students to measure practicality, as well as visual thinking test to measure the effectiveness of the media. Trial of the product is done 3 times in SMA Negeri 8 Batam in class X MIPA 5 which implements Curriculum 2013. The result of this research is a modulation system of inequality of two variables based on GeoGebra to visual thinking ability mathematically high school students of class X. Based on the research results obtained that the module is said Excellent (3.46), practical (3.04) and effective (89%), as well as students mathematical visual thinking ability with grade average of 89,61.
Keyword: Module, visual thinking, and GeoGebra.
DESKRIPSI DAN ANALISIS PENYEBARAN PENYAKIT MERS MELALUI MODEL REAKSI DIFUSI
Authors: Rozi Syamsyida
Published: February 2019

Penelitian ini diadakan berkaitan dengan mewabahnya penyakit Mers di kawasan Timur Tengah sejak 2012, bahkan hingga ke Korea pada 2015. WHO menyatakan bahwa hingga saat ini belum ada vaksin untuk mencegah manusia dari virus Mers sehingga masih ada kasus Mers baru yang dilaporkan dari beberapa negara. Oleh karena itu, pada artikel ini, dibentuk model matematika berbentuk persamaan reaksi difusi dan kinetik berupa sistem persamaan diferensial parsial (PDP) berkenaan dengan penyebaran virus Mers yang melibatkan tindakan karantina terhadap individu yang terinfeksi Mers. Kemudian keberadaan solusi traveling wave dari model tersebut diinvestigasi dan kecepatan penyebaran virusnya dianalisa. Berdasarkan model dan nilai parameter yang digunakan, diperoleh besaran basic reproduction number,  = 2,2 yang menunjukkan bahwa Mers menjadi epidemi di populasi, dan diperoleh kecepatan minimum penyebaran Mers sebesar 2,09 km/hari. Melalui analisa sensitifitas kecepatan dan gelombang traveling wave, diperoleh kesimpulan bahwa untuk mengontrol laju penyebaran virus Mers, maka sangat perlu mengkarantina individu yang terindikasi virus Mers segera. Keberadaan solusi traveling wave dari model dapat ditunjukkan melalui simulasi numerik dengan metode FTCS (Forward Time Center Space).
PENGEMBANGAN MODUL BERBASIS KONSTRUKTIVISME PADA MATA KULIAH ANALISIS VEKTOR DI UNRIKA
Authors: Husna Asmaul , Himmi Nailul
Published: February 2019

Abstrak. Tujuan Umum penelitian untuk mengembangkan modul Analisis Vektor yang valid di Program Studi Pendidikan Matematika UNRIKA. Tujuan khusus penelitian adalah menyediakan produk berupa modul Analisis Vektor berbasis  Konstruktivisme. Untuk mencapai tujuan tersebut, diperlukan suatu rancangan penelitian. Rancangan penelitian ini diuraikan dalam prosedur penelitian, prosedur penelitian yang digunakan model ADDIE yang terdiri dari 5 tahap, yaitu tahap analisis, tahap perancangan, tahap pengembangan, tahap implementasi dan tahap evaluasi.  Instrumen yang digunakan berupa lembar penilaian modul dalam bentuk checklist yang diberikan kepada ahli materi dan ahli media untuk mengukur kevalidan. Data hasil validasi dari validator terhadap seluruh aspek yang dinilai, dianalisis secara kuantitatif dengan memberikan skor sesuai dengan skala yang ditetapkan yaitu pada rentang 1-4 dengan kategori sangat kurang-sangat baik. Hasil skor disajikan dalam bentuk tabel kemudian dicari persentase skor tersebut. Adapun hasil validitas modul dari ahli media diperoleh sebesar 78,92% dengan kategori baik dan validitas modul dari ahli materi sebesar 78,57% dengan kategori baik.Kata Kunci: Analisis Vektor, Konstruktifisme, Modul Abstract. General Purpose of the study to develop a valid Vector Analysis module in the UNRIKA Mathematics Education Study Program. The specific purpose of the research is to provide products in the form of Constructivism-based Vector Analysis modules. To achieve this goal, a research design is needed. The design of this study is described in the research procedure, the research procedure used by ADDIE model consists of 5 stages, namely the analysis stage, the design phase, the development stage, the implementation stage and the evaluation stage. The instrument used was a module assessment sheet in the form of a checklist given to material experts and media experts to measure validity. The validation data from the validator on all aspects that are assessed, are analyzed quantitatively by giving a score according to the specified scale in the range 1-4 with very less-very good category. The score results are presented in the form of tables and then look for the percentage of the score. The results of module validity from media experts were 78,92% with good categories and module validity from material experts was 78,57% with good categories..Keywords: Constructivism, Module, Vector Analysis
PENGARUH ASSET SPESIFIK DAN KEPEMILIKAN ASING TERHADAP CORPORATE SUSTAINABILITY DENGAN MEDIASI CORPORATE GOVERNANCE
Authors: TANGKE PAULUS , HABBE ABDUL HAMID
Published: February 2019

This study aims to examine the effect of specific assets and foreign ownership on corporate sustainability with corporate governance as a mediation. This study is an empirical research using secondary data in the form of non-financial company data listed in the Indonesia Stock Exchange period 2011-2015. Based on the results of company sample selection conducted by purposive sampling method, it was selected 132 companies or 660 data years of the company. The theory used in this research is the stakeholders theory as the main theory with the theory of RBV as a supporting theory. The analytical method used in this study is path analysis using multiple regression test statistic tool - SPSS Version 24.

The results of this study indicate that specific assets have a positive and significant influence on corporate governance, but have a negative and insignificant effect on corporate sustainability. While foreign ownership has no effect on corporate governance but has negative and significant influence on corporate sustainability. Sobel test shows that Corporate governance in specific asset relation with corporate sustainability in this research is classified as type full mediation, but in foreign ownership relationship with corporate sustainability, corporate governance variable is classified as type no mediation
Drivers of Personal Safety in Agriculture: A Case Study with Pesticide Operators
Authors: Damalas Christos A. , Koutroubas Spyridon D. , Abdollahzadeh Gholamhossein
Published: February 2019

Agriculture is a hazardous occupational industry for farmers and farm workers; therefore, decisions to improve safety in the working place require understanding behavior of farmers and farm workers and factors affecting it. This study examined factors influencing perceived importance of personal safety and safe behavior of farmers in terms of personal protective equipment (PPE) use in pesticide spraying. Data were collected from a previous survey of farmers in rural areas of northern Greece. Over half of the farmers (55.4%) perceived low importance of personal safety in pesticide spraying. Perceived importance of personal safety increased in young farmers, with high education level, and large land area as well as with high perception of risk, knowledge of pesticide toxicity, seminar in pesticide use, access to internet, and perceived usefulness of PPE. Most farmers showed unsafe behavior in PPE use in terms of using long-sleeved shirt, long pants, chemical resistant gloves, socks, and shoes (58.9%). Farmers perceived low risk of pesticides (65.2%), despite the fact that two out of three farmers (66.1%) perceived high usefulness of PPE. Safe behavior in pesticide use increased in young farmers, with high education level, and small land area as well as with high perception of risk, knowledge of pesticide toxicity, seminar in pesticide use, access to internet, and perceived usefulness of PPE. Binary logistic regression analysis showed that knowledge of pesticide toxicity, education, age, and farm size were significant predictors of perceived importance of personal safety. In addition, self-confidence in spraying, following colleagues’ behaviors, risk perception, knowledge of pesticide toxicity, and farm size were significant predictors of safe behavior in terms of PPE use during pesticide spraying. Findings highlight differences in how farmers perceive personal safety and how they finally respond in daily action with respect to personal safety measures. Perception of risk, knowledge of pesticide toxicity, and farm size were common significant predictors for both variables. Lifelong education targeting promotion of knowledge about pesticide risks among farmers should be always a priority.
Voltage Ride through Control Strategy of Modular Multilevel Converter under Unbalanced Voltage Sag
Authors: Hakimi Seyed Mehdi , Hajizadeh Amin
Published: February 2019

This paper develops modeling and describes a control strategy for a modular multilevel converter (MMC) for grid-connected renewable energy systems. The proposed model can be used to simulate MMC activity during normal and faulty situations. Firstly, a dynamic model of a grid-connected MMC (GC-MMC), based upon the symmetrical component of voltages and currents, was designed. Then an adaptive robust control approach was established in order to follow the reference currents of the converter and stabilize the submodule (SM) capacitor voltage. The positive and negative sequences of reference currents that were given from the demanded active and reactive power during grid voltage disturbance and a normal situation were then utilized in control loops. Finally, the numerical results for the performance of the MMC throughout voltage sag conditions and the effect of uncertainties on the filter parameters during changing power demands were evaluated. The results specified that the current control strategy is more potent under voltage sag situations and able to fulfill the stability requirements of the MMC.
Identification and Description of Outliers in the Densmore Collection of Native American Music
Authors: Neubarth Kerstin , Conklin Darrell
Published: February 2019

This paper presents a method for outlier detection in structured music corpora. Given a music collection organised into groups of songs, the method discovers contrast patterns which are significantly infrequent in a group. Discovered patterns identify and describe outlier songs exhibiting unusual properties in the context of their group. Applied to the collection of Native American music collated by Frances Densmore (1867–1957) during fieldwork among several North American tribes, and employing Densmore’s music content descriptors, the proposed method successfully discovers a concise set of patterns and outliers, many of which correspond closely to observations about tribal repertoires and songs presented by Densmore.
Mode Separation for Multimodal Ultrasonic Lamb Waves Using Dispersion Compensation and Independent Component Analysis of Forth-Order Cumulant
Authors: Chen Xiao , Ma Dandan
Published: February 2019

Ultrasonic Lamb wave testing has been successfully applied in nondestructive testing. However, because of Lamb wave multimodal and dispersion characteristics, the received signals are often multimodal and overlapping, which makes them very complicated. This paper proposes a mode separation method by combining dispersion compensation with the independent component analysis of fourth-order cumulant. Taking two-mode overlapped signals as an example, the single-mode dispersion compensation is performed according to the measured distance difference between the two sets of signals. The two sets of signals are returned to the same distance. The fourth-order cumulant independent component analysis method is further used to process the Lamb wave signals of different superposition situations at the same distance. The corresponding mode signal contained in the two sets of signals is separated through the joint diagonalization of the whitened fourth-order cumulant matrix. The different modes are compensated and separated successively, achieving the multimodal signal separation. Experimental results in steel plates show that the presented method can accurately achieve mode separation for the multimodal overlapping Lamb waves. This is helpful for the signal processing of multimodal Lamb waves.
Immunometabolic Links between Estrogen, Adipose Tissue and Female Reproductive Metabolism
Authors: Eaton Sally A. , Sethi Jaswinder K.
Published: February 2019

The current knowledge of sex-dependent differences in adipose tissue biology remains in its infancy and is motivated in part by the desire to understand why menopause is linked to an increased risk of metabolic disease. However, the development and characterization of targeted genetically-modified rodent models are shedding new light on the physiological actions of sex hormones in healthy reproductive metabolism. In this review we consider the need for differentially regulating metabolic flexibility, energy balance, and immunity in a sex-dependent manner. We discuss the recent advances in our understanding of physiological roles of systemic estrogen in regulating sex-dependent adipose tissue distribution, form and function; and in sex-dependent healthy immune function. We also review the decline in protective properties of estrogen signaling in pathophysiological settings such as obesity-related metaflammation and metabolic disease. It is clear that the many physiological actions of estrogen on energy balance, immunity, and immunometabolism together with its dynamic regulation in females make it an excellent candidate for regulating metabolic flexibility in the context of reproductive metabolism.
Development of a New Span-Morphing Wing Core Design
Authors: Bishay Peter L. , Burg Erich , Akinwunmi Akinwande , Phan Ryan , Sepulveda Katrina
Published: February 2019

This paper presents a new design for the core of a span-morphing unmanned aerial vehicle (UAV) wing that increases the spanwise length of the wing by fifty percent. The purpose of morphing the wingspan is to increase lift and fuel efficiency during extension, to increase maneuverability during contraction, and to add roll control capability through asymmetrical span morphing. The span morphing is continuous throughout the wing, which is comprised of multiple partitions. Three main components make up the structure of each partition: a zero Poisson’s ratio honeycomb substructure, telescoping carbon fiber spars and a linear actuator. The zero Poisson’s ratio honeycomb substructure is an assembly of rigid internal ribs and flexible chevrons. This innovative multi-part honeycomb design allows the ribs and chevrons to be 3D printed separately from different materials in order to offer different directional stiffness, and to accommodate design iterations and future maintenance. Because of its transverse rigidity and spanwise compliance, the design maintains the airfoil shape and the cross-sectional area during morphing. The telescoping carbon fiber spars interconnect to provide structural support throughout the wing while undergoing morphing. The wing model has been computationally analyzed, manufactured, assembled and experimentally tested.
An Attribute Reduction Method Using Neighborhood Entropy Measures in Neighborhood Rough Sets
Authors: Sun Lin , Zhang Xiaoyu , Xu Jiucheng , Zhang Shiguang
Published: February 2019

Attribute reduction as an important preprocessing step for data mining, and has become a hot research topic in rough set theory. Neighborhood rough set theory can overcome the shortcoming that classical rough set theory may lose some useful information in the process of discretization for continuous-valued data sets. In this paper, to improve the classification performance of complex data, a novel attribute reduction method using neighborhood entropy measures, combining algebra view with information view, in neighborhood rough sets is proposed, which has the ability of dealing with continuous data whilst maintaining the classification information of original attributes. First, to efficiently analyze the uncertainty of knowledge in neighborhood rough sets, by combining neighborhood approximate precision with neighborhood entropy, a new average neighborhood entropy, based on the strong complementarity between the algebra definition of attribute significance and the definition of information view, is presented. Then, a concept of decision neighborhood entropy is investigated for handling the uncertainty and noisiness of neighborhood decision systems, which integrates the credibility degree with the coverage degree of neighborhood decision systems to fully reflect the decision ability of attributes. Moreover, some of their properties are derived and the relationships among these measures are established, which helps to understand the essence of knowledge content and the uncertainty of neighborhood decision systems. Finally, a heuristic attribute reduction algorithm is proposed to improve the classification performance of complex data sets. The experimental results under an instance and several public data sets demonstrate that the proposed method is very effective for selecting the most relevant attributes with great classification performance.
Application of Hydrodynamic Cavitation for Improving Methane Fermentation of Sida hermaphrodita Silage
Authors: Zieliński Marcin , Rusanowska Paulina , Krzywik Aleksandra , Dudek Magda , Nowicka Anna , Dębowski Marcin
Published: February 2019

Hydrodynamic cavitation was recently applied as a biomass pretreatment method. Most of the studies which used hydrodynamic cavitation were applied to pretreated sugarcane bagasse or reed. High biomass yield of Sida hermaphrodita points out the necessity of studies on its effective pretreatment before methane fermentation, especially because its “wood-like” characteristics could present different disintegration properties than other lignocellulose biomass. Thus, the aim of the study was to investigate the influence of duration of hydrodynamic cavitation on lignocellulose composition in Sida hermaphrodita silage, and the assessment of disintegrated biomass as a substrate for methane fermentation. The study showed a slight decrease in lignin, cellulose, and hemicellulose content in biomass after hydrodynamic cavitation, which resulted in a higher content of carbohydrates in the liquid fraction of disintegrated substrates. Methane production was 439.1 ± 45.0 L CH4/kg total solids (TS) from the substrate disintegrated for 20 min. However, the most effective time for methane production was hydrodynamic cavitation of the substrate for 5 min. At this pretreatment duration, the highest values for chemical oxygen demand (COD), total organic carbon (TOC), and carbohydrate reduction were also noted. The study proved that hydrodynamic cavitation applied for 5 min allowed obtaining an energy profit of 0.17 Wh/g TS. The studies on a laboratory scale indicated that the technology of hydrodynamic cavitation of Sida hermaphrodita could be economically applied for methane fermentation on a large scale.
Welfare Challenges Influence the Complexity of Movement: Fractal Analysis of Behaviour in Zebrafish
Authors: Deakin Anthony G. , Spencer Joseph W. , Cossins Andrew R. , Young Iain S. , Sneddon Lynne U.
Published: February 2019

The ability to assess welfare is an important refinement that will ensure the good condition of animals used in experimentation. The present study investigated the impact of invasive procedures on the patterns of movement of zebrafish (Danio rerio). Recordings were made before and after fin clipping, PIT tagging and a standard pain test and these were compared with control and sham handled zebrafish. The fractal dimension (FD) from the 3D trajectories was calculated to determine the effect of these treatments on the complexity of movement patterns. While the FD of zebrafish trajectories did not differ over time in either the control or sham group, the FDs of the treatment groups reduced in complexity. The FD of fish injected with different strengths of acetic acid declined in a dose-dependent manner allowing us to develop an arbitrary scale of severity of the treatments. The 3D trajectory plots from some groups indicated the presence of repetitive swimming patterns akin to stereotypical movements. When administered with lidocaine, which has analgesic properties, the movement complexity of fin clipped fish reverted to a pattern that resembled that of control fish. Fractal analysis of zebrafish locomotion could potentially be adopted as a tool for fish welfare assessment.
Searching for Gamma-Ray Millisecond Pulsars: Selection of Candidates Revisited
Authors: Dai Xuejie , Wang Zhongxiang , Vadakkumthani Jithesh
Published: February 2019

We are starting a project to find γ -ray millisecond pulsars (MSPs) among the unidentified sources detected by the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope (Fermi), by radio observations. The selection of good candidates from analysis of the LAT data is an important part of the project. Given that there is more than 10 years worth of LAT data and the advent of the newly released LAT 8-year point source list (FL8Y), we have conducted a selection analysis, on the basis of our previous analysis, and report the results here. Setting the requirements for the unidentified sources in FL8Y of Galactic latitudes | b | > 5 ∘ and curvature significances >3 σ , there are 202 sources with detection signficances >6 σ . We select 57 relatively bright ones (detection significances >15 σ ) and analyze their 10.2 years of LAT data. Their variability is checked to exclude variable sources (likely blazars), test statistic maps are constructed to avoid contaminated sources, and curvature significances are re-obtained and compared to their γ -ray spectra to exclude non-significant sources. In the end, 48 candidates are found. Based on the available information, mostly from multi-wavelength studies, we discuss the possible nature of several of the candidates. Most of these candidates are currently being observed with the 65-meter Shanghai Tian Ma Radio Telescope.
Sex Differences in Lifestyle Behaviors among U.S. College Freshmen
Authors: Olfert Melissa D. , Barr Makenzie L. , Charlier Camille C. , Greene Geoffrey W. , Zhou Wenjun , Colby Sarah E.
Published: February 2019

Within lifestyle behavior research, the sex of populations causes differences in behaviors and outcomes of studies. This cross-sectional study investigated lifestyle behavior patterns in college students, examining sex differences in four areas: Nutrition, physical activity, sleep, and stress. Data from over 1100 college freshmen across 8 United States universities were used for this cross-sectional analysis. Self-reported data assessed fruit and vegetable intake, fat percent intake, physical activity, perceived stress, and sleep quality. Statistical analysis included Pearson chi-squared and Mann–Whitney’s U tests for scores by sex. Likewise, healthy cut-offs were used to determine frequency of participants within range of the five tools. Males reported higher intake of both fruits and vegetables, and percent energy from fat than females. Males also reported higher physical activity levels, lower stress levels, and poorer sleep quality than females. Of the five self-reported tools, males were found to have a larger frequency of participants with healthy ranges than females. In a large college freshmen sample, sex was found to be related to general lifestyle behaviors which strengthen results reported in the previous literature. These findings shed light on the need for lifestyle behavior interventions among at-risk college students to enhance their behaviors to healthy levels.
Numerical and Experimental Investigation of the 4-Quadrant Behavior of Different Mixed Flow Diffuser Pumps
Authors: Höller Stefan , Benigni Helmut , Jaberg Helmut
Published: February 2019

Besides operating a centrifugal pump under normal conditions there are additional operating conditions possible; for example, a pump operated as turbine. Another example would be a pump trip where there are several abnormal operating conditions possible when the direction of flow and/or the direction of rotation are changing. The machine behavior in every possible operation condition can be represented by the complete pump characteristics, often called the 4-quadrant (4Q) behavior of a centrifugal pump. To gather the 4Q behavior, a test rig allowing the flow direction as well as the rotation direction to be reverted is necessary, with time-consuming measurements at variable positive and negative discharge in both directions of rotation the complete pump characteristics are evaluated. In the present study, an approach to investigate the complete pump characteristics by means of computational fluid dynamics (CFD) calculations is presented. With steady-state calculations and additional transient CFD investigations in the normal operating conditions, the whole pump characteristics were calculated accurately. Two different types of mixed flow diffuser pumps were investigated—one equipped with adjustable impeller blades, the second one with comparable low specific speed. Experimental verifications have shown a remarkably good agreement. Furthermore, an exemplary numerical waterhammer analysis shows the successful application of the presented approach.
Effects of Different Comorbidities on Health-Related Quality of Life among Respiratory Patients in Vietnam
Authors: Ngo Chau Quy , Phan Phuong Thu , Vu Giap Van , Pham Quyen Le Thi , Nguyen Long Hoang , Vu Giang Thu , Tran Tung Thanh , Nguyen Huong Lan Thi , Tran Bach Xuan , Latkin Carl A. , Ho Cyrus S. H. , Ho Roger C. M.
Published: February 2019

Comorbidities are common in respiratory disease patients and have been well-known to impact their quality of life. The objective of this study is to estimate the minimal clinically important difference (MCID) of the health-related quality of life (HRQOL) among respiratory disease patients with different comorbidities in a Vietnamese tertiary hospital. We performed a cross-sectional study from October to November 2016 at the Respiratory Center of Bach Mai Hospital, Hanoi, with a total of 508 participants. Information about socio-economic characteristics, HRQOL and comorbidities of participants was collected. ANOVA was used to identify MCID between patients with and without specific comorbid conditions. Tobit regression was used to explore the associations between comorbidities and the HRQOL. Results showed that the prevalence of cardiovascular comorbidities was 23.8%, followed by musculoskeletal diseases (12.0%), digestive diseases (11.8%), endocrine diseases (10.0%), kidney diseases (5.1%) and ear, nose, and throat diseases (4.5%). Regarding HRQOL, having a problem in pain/discomfort was observed in 61.0% of participants, followed by anxiety/depression (48.2%). Mean EQ-5D index was 0.66 (SD (Standard Deviation) = 0.31). The significant MCID (p < 0.05) was found between patients with and without cardiovascular diseases, musculoskeletal diseases, kidney diseases, and endocrine diseases. The multivariate regression model showed that only musculoskeletal diseases were found to be related with the marked decrement of EQ-5D index score (Coef. = −0.13; 95% CI (Confident Interval) = −0.23; −0.02). Suffering at least one chronic illness was correlated to the marked decrease of EQ-5D index score (Coef. = −0.09; 95% CI = −0.17; −0.01). These results underline the importance of appropriate pain management as well as the provision of an interprofessional care approach to patients in order to alleviate the burden of comorbidities to their treatment outcomes and HRQOL.
Numerical Simulations of the Hydraulic Performance of a Breakwater-Integrated Overtopping Wave Energy Converter
Authors: Palma Giuseppina , Mizar Formentin Sara , Zanuttigh Barbara , Contestabile Pasquale , Vicinanza Diego
Published: February 2019

OBREC is the acronym that stands for Overtopping Breakwater for Energy Conversion. It is a multifunctional device aimed to produce energy from the waves, while keeping the harbour area protected from flooding. In this paper, the inclusions of a berm to reduce wave reflection, the shape of the sloping plate to maximise wave overtopping and the reservoir width and the crown wall shape to maximise wave energy capture while keeping the harbour safety were analysed to optimize the hydraulic and structural performances of the device. Several configurations were numerically investigated by means of a 2DV RANS-VOF code to extend the results already obtained during previous experimental campaigns. The wave reflection coefficient, the average wave overtopping flows and the wave loadings along the structure are computed, compared with existing formulae and discussed with reference to the OBREC prototype installed in the Port of Naples.
Land Governance in Post-Conflict Settings: Interrogating Decision-Making by International Actors
Authors: Betge David
Published: February 2019

Humanitarian and development organizations working in conflict-affected settings have a particular responsibility to do no harm and contribute to the wellbeing of the population without bias. The highly complex, politicized realities of work in conflict- and post-conflict settings often require quick, pragmatic and results-oriented decisions, the foundations of which remain frequently implicit. Such decisions might follow an intrinsic logic or situational pragmatism rather than intensive deliberation. This paper reflects on the realities of working on land governance in post-conflict settings shaped by migration, ethnic division, power struggles and limited statehood. Using case examples from the Democratic Republic of Congo (DRC) and Burundi, this paper reflects on the drivers of decisions around land governance in such contexts in a structured, theoretically informed way. Drawing on the author’s own experience with supporting land rights work and utilizing Giddens’ concept of the Duality of Structure, this article provides an analysis of actors and structures that sheds light on the factors that affect the decision-making of practitioners relating to land rights in post-conflict areas of limited statehood.
Examination of the High Tensile Ductility Improvement in an As-Solutionized AA7075 Alloy with the Aid of a Friction Stir Process
Authors: Ku Ming-Hsiang , Hung Fei-Yi , Lui Truan-Sheng
Published: February 2019

The ductility enhancement of an AA7075 aluminum alloy aided by a friction stir process (FSP) and various heat treatments was investigated and compared in terms of outcome with full annealing (O). The results indicate that a big improvement in the tensile ductility was achieved by freezing the sample at temperatures below 0 °C after the solution treatment and water quenching (W treatment), and further improvement could be acquired via a friction stir process due to grain refinement (<6 μm). Thus, the observed improvement in tensile ductility can be explained by the fact that the W treatment and friction stir processing scheme had an increased strain-hardening effect and decreased the presence of intermetallic particles that are harmful to uniform tensile deformation, consequently causing strain localization in the early stage of tensile deformation, which suggests that these treatment are a potential solution for insufficient formability. In general, the elongation to failure values for the W and FSP-treated specimens (>40%) were at least 1.5-fold greater than that of the annealed alloy. In addition, serrated flow could be observed in the tensile flow curves, and both the Piobert–Lüders effect and the Portevin–LeChatelier (PL) effect could be observed. The enhancement in the tensile ductility was examined in terms of the existence of intermetallic particles and the supersaturated concentration of the solid solution.
Emotional Eating, Health Behaviours, and Obesity in Children: A 12-Country Cross-Sectional Study
Authors: Jalo Elli , Konttinen Hanna , Vepsäläinen Henna , Chaput Jean-Philippe , Hu Gang , Maher Carol , Maia José , Sarmiento Olga L. , Standage Martyn , Tudor-Locke Catrine , Katzmarzyk Peter T. , Fogelholm Mikael
Published: February 2019

Eating in response to negative emotions (emotional eating, EE) may predispose an individual to obesity. Yet, it is not well known how EE in children is associated with body mass index (BMI) and health behaviours (i.e., diet, physical activity, sleep, and TV-viewing). In the present study, we examined these associations in a cross-sectional sample of 5426 (54% girls) 9–11-year-old children from 12 countries and five continents. EE, food consumption, and TV-viewing were measured using self-administered questionnaires, and physical activity and nocturnal sleep duration were measured with accelerometers. BMI was calculated using measured weights and heights. EE factor scores were computed using confirmatory factor analysis, and dietary patterns were identified using principal components analysis. The associations of EE with health behaviours and BMI z-scores were analyzed using multilevel models including age, gender, and household income as covariates. EE was positively and consistently (across 12 study sites) associated with an unhealthy dietary pattern (β = 0.29, SE = 0.02, p < 0.0001), suggesting that the association is not restricted to Western countries. Positive associations between EE and physical activity and TV viewing were not consistent across sites. Results tended to be similar in boys and girls. EE was unrelated to BMI in this sample, but prospective studies are needed to determine whether higher EE in children predicts the development of undesirable dietary patterns and obesity over time.
Preparation and Thermoelectric Properties Study of Bipyridine-Containing Polyfluorene Derivative/SWCNT Composites
Authors: Pan Chengjun , Wang Luhai , Zhou Wenqiao , Cai Lirong , Xie Dexun , Chen Zhongming , Wang Lei
Published: February 2019

Polymer/inorganic thermoelectric composites have witnessed rapid progress in recent years, but most of the studies have focused on the traditional conducting polymers. The limited structures of traditional conducting polymers restrain the development of organic thermoelectric composites. Herein, we report the preparation and thermoelectric properties of a series of composites films based on SWCNTs and bipyridine-containing polyfluorene derivatives. The value of the power factor around 12 μW m−1 K−2 was achieved for the composite F8bpy/SWCNTs with a mass ratio of 50/50, and the maximum value of 62.3 μW m−1 K−2 was obtained when the mass ratio reached 10/90. Moreover, taking advantage of the bipyridine unit could chelate various kinds of metal ions to form polymer complexes. The enhanced power factor of 87.3 μW m−1 K−2 was obtained for composite F8bpy-Ni/SWCNTs with a mass ratio of 50/50. Finally, the thermoelectric properties of the bipyridine-containing polyfluorene derivative/SWCNT composites were conveniently tuned by chelating with different metal ions.
Highly-Loaded Thermoplastic Polyurethane/Lead Zirconate Titanate Composite Foams with Low Permittivity Fabricated using Expandable Microspheres
Authors: Petrossian Gayaneh , Hohimer Cameron J. , Ameli Amir
Published: February 2019

The sensitivity enhancement of piezocomposites can realize new applications. Introducing a cellular structure into these materials decreases the permittivity and thus increases their sensitivity. However, foaming of piezocomposites is challenging because of the high piezoceramic loading required. In this work, heat-expandable microspheres were used to fabricate thermoplastic polyurethane (TPU)/lead zirconate titanate (PZT) composite foams with a wide range of PZT content (0 vol % to 40 vol %) and expansion ratio (1–4). The microstructure, thermal behavior, and dielectric properties of the foams were investigated. Composite foams exhibited a fine dispersion of PZT particles in the solid phase and a uniform cellular structure with cell sizes of 50–100 μm; cell size decreased with an increase in the PZT content. The total crystallinity of the composites was also decreased as the foaming degree increased. The results showed that the relative permittivity (εr) can be effectively decreased by an increase in the expansion ratio. A maximum of 7.7 times decrease in εr was obtained. An extended Yamada model to a three-phase system was also established and compared against the experimental results with a relatively good agreement. This work demonstrates a method to foam highly loaded piezocomposites with a potential to enhance the voltage sensitivity.
Agent-Based Simulation of Value Flow in an Industrial Production Process
Authors: Parv Luminita , Deaky Bogdan , Nasulea Marius Daniel , Oancea Gheorghe
Published: February 2019

The current competitive environment demands companies to be more and more efficient. In order to increase manufacturing efficiency, two apparently independent approaches have emerged: lean strategies, focusing on identifying and minimizing non-added value activities, identifying wastes in the system and their elimination, and information tools for planning and controlling activities. In this paper, a manufacturing system was considered for which it was necessary to increase the production capacity in order to respond to the customer’s increased demand. A practical case study in the automotive industry for a medium-sized enterprise was considered. In order to investigate the production process parameters and to implement lean principles, Value Stream Mapping (current analysis and optimized solution) and Anylogic agent-based simulations were carried out. Based on this, the lean performances, specific for the target VSM, were evaluated in terms of key performance indicators. The benefits of integrating agent-based simulation in the design and analysis of the value flow in the production chain are the capitalization of the information offered by Value Stream Mapping and the possibility to choose the best one from the possible scenarios. It generates important time and cost reductions without further resource waste.
From a Jewish Communist to a Jewish Buddhist: Allen Ginsberg as a Forerunner of a New American Jew
Authors: Ariel Yaakov
Published: February 2019

The article examines Allen Ginsberg’s cultural and spiritual journeys, and traces the poet’s paths as foreshadowing those of many American Jews of the last generation. Ginsberg was a unique individual, whose choices were very different other men of his era. However, it was larger developments in American society that allowed him to take steps that were virtually unthinkable during his parents’ generation and were novel and daring in his time as well. In his childhood and adolescence, Ginsberg grew up in a Jewish communist home, which combined socialist outlooks with mild Jewish traditionalism. The poet’s move from communism and his search for spirituality started already at Columbia University of the 1940s, and continued throughout his life. Identifying with many of his parents’ values and aspirations, Ginsberg wished to transcend beyond his parents’ Jewish orbit and actively sought to create an inclusive, tolerant, and permissive society where persons such as himself could live and create at ease. He chose elements from the Christian, Jewish, Native-American, Hindu, and Buddhist traditions, weaving them together into an ever-growing cultural and spiritual quilt. The poet never restricted his choices and freedoms to one all-encompassing system of faith or authority. In Ginsberg’s understanding, Buddhism was a universal, non-theistic religion that meshed well with an individualist outlook, and offered personal solace and mindfulness. He and other Jews, who followed his example, have seen no contradiction between practicing Buddhism and Jewish identity and have not sensed any guilt. Their Buddhism has been Western, American, and individualistic in its goals, meshing with other interests and affiliations. In that, Ginsberg served as a model and forerunner to a new kind of Jew, who takes pride in his heritage, but wished to live his life socially, culturally and spiritually in an open and inclusive environment, exploring and enriching herself beyond the Jewish fold. It has become an almost routine Jewish choice, reflecting the values, and aspirations of many in the Jewish community, including those who chose religious venues within the declared framework of the Jewish community.
Colorimetric and Ratiometric Fluorescence Dual-Mode Sensing of Glucose Based on Carbon Quantum Dots and Potential UV/Fluorescence of o-Diaminobenzene
Authors: Zhai Hong , Bai Yunfeng , Qin Jun , Feng Feng
Published: February 2019

A novel colorimetric and ratiometric fluorescence sensor was constructed by using carbon quantum dots (CQDs) and o-diaminobenzene (ODB). Unlike ODB by itself, ODB oxide (oxODB) not only emits fluorescence, but also produces ultraviolet (UV) absorption. Therefore, on the basis of the potential optical properties of ODB, glucose oxidase (Gox) and horseradish peroxidase (HRP) were introduced into a CQDs–ODB system for the quantitative oxidation of ODB. When glucose is present, it is oxidized by oxygen under the catalytic action of its oxidase to form hydrogen peroxide. Hydrogen peroxide is a strong oxidant that can rapidly oxidize ODB through the catalysis of horseradish peroxidase. oxODB can cause changes in the fluorescence ratio (I550/I446) and absorbance ratio (A/A0). At the same time, the color of the detection solution can also change under sunlight and ultraviolet lamps. Therefore, glucose can be quantitatively detected by ratiometric fluorescence and colorimetry simultaneously, and semi-quantitatively detected by observing the colors with sunlight and ultraviolet lamps of 365 nm. This increases not only the convenience but also the accuracy of detection. In addition, this sensor has good selectivity and can be used for the determination of glucose in serum, providing a new idea for the development of blood glucose sensors.