bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of Dispersive Liquid-Liquid Microextraction Procedure for Trace Determination of Malathion Pesticide in Urine Samples
Authors: RAMIN Maryam , KHADEM Monireh , OMIDI Fariborz , POURHOSEIN Mehran , GOLBABAEI Farideh , SHAHTAHERI Seyed Jamaleddin
Published: July 2020

Background: Measurement of pesticides in biological matrices is become a serious challenge for researches because of their very low concentration in different matrices. The aim of this study was to develop a new sample preparation method with high accuracy and validity, simplicity and short retention time for determination of malathion.
Methods: Dispersive liquid-liquid micro-extraction (DLLME) technique coupled with high-performance liquid chromatography equipped with ultraviolet detector (HPLC-UV) developed for trace extraction and determination of malathion pesticide in human urine samples. This study was done in 2017 at Tehran University of Medical Sciences, Tehran, Iran. One variable at a time (OVAT) method was used to optimize parameters affecting the malathion extraction. Different parameters such as extraction solvent, disperser solvent, and volume of the extraction solvent, volume of the disperser solvent, centrifugation time and speed, salt addition, and sample pH were studied and optimized.
Results: Under the optimized conditions, the limit of detection and enrichment factor of the method were 0.5 µg L-1 and 200, respectively. The calibration curve was linear in the concentration range of 2-250 µg L-1 . The relative standard deviation for six replicate experiments at 200 µg L-1 concentration was less than 3%. The relative recoveries of spiked urine samples were 96.3%, 101.7% and 97.3% at three different concentration levels of 50, 200 and 1000 µg L-1 , respectively.
Conclusion: DLLME procedure was successfully developed for the extraction of malathion from human urine samples. Compared to other extraction techniques, the proposed procedure had some advantages such as shorter extraction time, better reproducibility, and higher enrichment factor.
Outbreak of Foodborne Botulism Associated with Improperly Earthenware Cheese (Koupé): A Case Report
Authors: FAGHIH SOLAYMANI, Parshang , RAHIMZADEH Ardeshir , MOSTAFAVI Farideh
Published: July 2020

Here we report the consumption of traditional cottage cheese (Koupé) in western Iran, as a new way of transmission of botulism. All the patients (a nine member family) had at least two specific symptoms of botulism. Given the clinical symptoms and contact history, anti-toxins were injected in the early hours of hospital admission. On Jan 27, 2017, three patients clinically suspected of foodborne botulism were referred to the hospital in Sanandaj, western Iran from their local hospital in Baneh, western, Iran. Because of the worsening of clinical conditions, a 34-yr-old man with both gastrointestinal and neurological symptoms was admitted to the ICU, while other family members were treated in the infectious diseases ward of the hospital. The disease was diagnosed through isolating toxin A from the cheese and testing the serum sample of one of the patients. This case of botulism showed that traditional Koupé cheese could cause foodborne botulism. Hence, it is necessary to train and inform people about how to process and keep the cheese to prevent similar cases.
Effects of Physical Activity and Social Activity on Physical Health and Social Inclusion of Elderly People
Authors: POPOVIC Stevo , MASANOVIC Bojan
Published: July 2020

The article's abstract is no available.
Differences in Skin Health Outcomes According to Physical Activity Level among Korean Female College Students
Authors: LEE Jeong-Hyun , KIM Yeona , SO Wi-Young
Published: July 2020

The article's abstract is no available.
Prevalence, Trends and Associated Risk Factors of Overweight/Obesity among Rural-to-Urban Migrant Children in China
Authors: LU Jinkui , XU Yongsheng , XIANG Jianming
Published: July 2020

The article's abstract is no available.
Application of Continuing Care in Patients with Mild Cerebral Hemorrhage
Authors: ZHANG Min , YU Yang , CHEN Yujun , FAN Guihong
Published: July 2020

The article's abstract is no available.
Effects of Opium Use on Cardiovascular Mortality: A Critical Appraisal of a Topic
Authors: MOEZI Seyyed Ali , AZDAKI Nahid , KAZEMI Toba , MASHREGHI MOGHADDAM Hamid Reza , PARTOVI Neda , HAMIDI Fatemeh , HANAFI-BOJD Nazanin , JAFARNEJAD Majid , NAKHAEE Samaneh
Published: July 2020

The article's abstract is no available.
Prevalence of Malnutrition and its Related Factors among Pre-School (2-6 Years) Children in the Neighborhood of Chahestaneha, Bandar-Abbas, Iran
Authors: ABDULLAHI Kabir Ozigi , MUHAMMAD Fatima Mahmud , HOLAKOUIENAIENI Kourosh , KHOSRAVI Ahmad , LODHI Fahad Saqib , KAREEM Ahang Abdullah , KAMALI Aram Salih Mohammed Amin , SABAHAT Hasnain , SAEED Sami Najmaddin , HOSSEINI Mohammad Ali
Published: July 2020

The article's abstract is no available.
Detection of Heroin and Noscapine in Bile Specimen in a Body Packer
Authors: NAJAFI Nahid , MONTAZERI Mahmoud
Published: July 2020

The article's abstract is no available.
Determining critical flow parameters for the Poiseuille, Couette and Taylor – Couette flows
Authors: Kondratiev A.S. , Ogorodnikov K.F.
Published: July 2020

Based on a detailed analysis of the known Dou method for determining the critical parameters of a Newtonian fluid flow during the transition of a laminar flow regime to a turbulent one, an alternative to determining the critical Reynolds number for the Poiseuille and Couette flows in cylindrical, coaxial and flat channels, the article proposes a new mathematical justification of the Dou method leading to simpler calculation relations, while preserving the initial ideas about the physical conditions of the transition. New computing expressions for determining the critical Dou number for the generalized Poiseuille – Couette flow in a flat channel not considered by Dou are obtained. Analytical expressions for calculating critical parameters for the Taylor – Couette flow approximating experimental results for critical Reynolds numbers are given, as well as calcula-ted values of critical Dou numbers.
Techniques of testing algorithms for controlling spacecraft angular motion
Authors: Merkuryev S.A.
Published: July 2020

The paper considers the technique of the initial developing algorithms for controlling the angular motion of an automatic spacecraft as a solid body. The mathematical model of the control object is given by the Euler’s dynamic equations and kinematic equations written using the Rodrig — Hamilton parameters. The technique has a simple form and is intended for control algorithm rough testing. Its structure allows adding complexity in the initial model of the system by adding models of onboard devices and external effects. The efficiency of the method was tested on the example of working out an algorithm with a dead zone for the solar-pointing control mode of an automatic spacecraft. In this mode, a solar sensor was used as a measuring device, and flywheel engines were used as executive bodies. The results of simulation in the MathWorks MATLAB environment are presented.
On the structure of the optimal thrust for the “intermediate” aircraft model
Authors: Cherkasov O. Yu. , Smirnova N.V.
Published: July 2020

The paper considers a brachistochrone problem modification including in the objective function a fuel consumption penalty apart from the process time. The material point moves in a vertical plane under gravity, viscous nonlinear friction and traction. The trajectory slope angle and thrust are considered as a control variables. The Pontryagin maximum principle allows reducing the optimal control problem to a boundary value problem for a system of two nonlinear differential equations. Qualitative analysis of the resulting system allows studying the key features of extreme trajectories, including their asymptotic behavior. Extreme thrust control is obtained as a function of the velocity and the trajectory slope angle. The structure of extreme thrust is determined, and the number of switches is analytically determined. The results of numerical solving the boundary value problem are presented, illustrating the analytical conclusions.
Simulation of drip-rain effects by tribofatigue loading
Authors: Aliev A.A. , Ampilogov A.Yu.
Published: July 2020

The outer surfaces of aircraft are periodically subjected during flight to intense rain causing hydroerosion of the outer paintwork. The experimental evaluation of hydroerosion resistance is based on testing in high-speed water flow. The main drawback of such research is the bulkiness of the stands, high water and energy consumption, and, as a result, increased cost. As an alternative to drip-rain tests, their simulation by kinetically similar tribofatigue test according to the “ball on plate” scheme is proposed (vertical load is applied to the polymer coating on a rigid substrate through a steel ball). The process is cyclically repeated until the coating is worn to the specified thickness. The experimentally obtained tribofatigue characteristics then can be converted into close-meaning estimates of erosion resistance. CAAPCOAT-B274-ASP108 polyurethane, previously tested for rain erosion, was selected as the sample. For quantitative evaluation of the transition from drip-rain loading to equivalent tribofatigue one the contact mechanics formulas were used by calculating the force of the drip impact and the stress in the contact spot. Tribofatigue tests were conducted on the UMT-2 TriboLab unit. At equal calculated contact stress levels the wear rate under tribofatigue loading was almost 7 times higher compared to the conditions of rain-drop erosion. The reason may be a scale factor due to the actual difference in contact areas under drip and tribofatigue loading, as well as the failure to take into account the dynamics of waves after the impact of drops. The obtained results of tribofatigue tests can give an estimated value of the hydroerosion resistance of the coating.
CIÊNCIA E POLÍTICA: REFLEXÕES CRÍTICAS SOBRE A PESQUISA COMO ATO POLÍTICO
Authors: CONSUELO ANDREATTA WHITAKER DULCE
Published: July 2020

Este ensaio parte de questões metodológicas e de experiência pessoal para chegar às questões políticas. Considera os dados de qualquer pesquisa como construídos pelo pesquisador, além de lembrar suas intenções e sua responsabilidade enquanto cientista que deve ter me mente o que será feito com seus resultados (pelo poder), face à transformação de ciência em tecnologia, já que essa é a principal característica do capitalismo desde a Revolução Industrial - o que leva à dominação ideológica via mercadoria. São discutidas as consequências desse processo e sugeridas propostas no sentido de desvendar a ideologia e chegar à contra ideologia, praticando a pesquisa como ato  político
CONFERENCIA DE APERTURA IV CONISE 2019 La investigación un acto político: Una experiencia desde las IUS
Authors: Mvillagomez
Published: July 2020

La educación es o un acto político ya que con ella tomamos una postura frente a la realidad y en torno al tipo de sociedad que queremos construir; lo que queremos transformar y por donde hemos de transitar. Como acto político, la educación tiene siempre un carácter prospectivo, tiene un sentido utópico que nos provee de un horizonte hacia el cual hemos de caminar, es el sueño de la construcción de otra realidad posible. Para las Instituciones Salesianas de Educación Superior, nuestra opción es clara,  por los y las jóvenes de clases trabajadoras y de sectores vulnerables. Estamos comprometidos en todo el mundo a acompañarlos  para construir con ellos un futuro mejor. Entender qué es lo que debemos transformar en la educación, desde y con ella, nos exige comprender la realidad  y para ello hemos de centrar nuestros esfuerzos, desde la academia en el ejercicio de la investigación social y educativa comprometida con los jóvenes y la construcción de un mundo mejor.  La investigación educativa como tal, tiene siempre una intención pragmática, nos permite no solo comprender la realidad de los y las jóvenes (sujetos) a quienes educamos, sino que nos provee de los datos para interrogar nuestras prácticas y mejorarlas; para ofrecer alternativas, para agenciar mejores proyectos educativos y pedagógicos; para aprender de nuestras experiencias, pues como universidades salesianas, tenemos la exigencia de mirarnos, interpelarnos y esforzarnos por hacer de la educación un acto de amor y de vida.En esta lína, mostramos la experiencia y los resultados de la investigación  "Mujer indígena y educació superior" que lleva adelante el Grupo de Investigación Educación e Interculturalidad de la Universidad Politécnica Salesiana del Ecuador y,  que tienen como objetivo central: analizar el papel de la IUS en el empoderamiento, autonomía y emancipación de las mujeres indígenas. Finalmente, centramos la reflexión en la potencialidad transformadora de la educación y de la investigación desde un compromiso ético-político con la construcción de una vida mejor para los y las jóvenes que se educan en las IUS.
Educación Popular en América Latina. Trazas históricas y nudos estratégicos para el siglo XXI
Authors: FabianCabaluz FabianCabaluz
Published: July 2020

El artículo que presentamos se organiza a partir de dos apartados: en el primero de ellos, se presentan cinco trazas históricas de la educación popular latinoamericana, a saber: las prácticas y discursos de educación emancipadora promovidos por Simón Rodríguez y José Martí durante el siglo XIX, las experiencias educativas y pedagógicas impulsadas por el naciente movimiento obrero y popular entre fines del siglo XIX y comienzos del XX, la experiencia de la Escuela Ayllu de Warisata en Bolivia durante la década de los treinta del siglo pasado, el surgimiento durante la década de los sesenta de la pedagogía de la liberación elaborada por Paulo Freire, y finalmente, las prácticas y discursos de educación popular desplegados contra las dictaduras cívico-militares en la región.  Y en el segundo apartado, se retoman cuatro debates estratégicos de los cuales ha sido parte la educación popular latinoamericana en lo que va transcurrido del siglo XXI, el primero referido al problema de la soberanía nacional y popular, el segundo vinculado a las luchas por descolonizar el campo educativo y pedagógico, el tercero asociado a las articulaciones entre educación popular y feminismo en el marco de las luchas contra el patriarcado, y el cuarto concerniente a la relevancia de luchar desde la educación popular por la defensa y el robustecimiento de la educación pública.
The Oligocene/Miocene boundary in the ON-Mol-1 and Weelde boreholes along the southern margin of the North Sea Basin, Belgium
Authors: MUNSTERMAN Dirk K. , DECKERS Jef
Published: July 2020

Based on palynologic interpretations, the Oligocene/Miocene boundary was identified in the cored samples of the ON-Mol-1 and Weelde boreholes in the southern North Sea Basin. In both boreholes, the presumed location of the Oligocene/Miocene boundary is marked by a thin gravel bed, which testifies of a hiatus, within a continuation of shelly, dark green to black fine glauconitic sands. In the Weelde borehole, the hiatus is relatively short as the dinocysts under- and overlying the gravel bed suggest a late(st) Chattian and early Aquitanian age. This study thereby for the first time indicates the presence of Aquitanian strata in the area. In the ON-Mol-1 borehole, located south of the Weelde borehole, the hiatus is longer as dinocysts under- and overlying the gravel bed suggest an early Chattian and late Aquitanian age. The wider ranges of the hiatus might be the result of the combination of erosion/non-deposition of late Chattian strata and the gradual transgression of the southern North Sea Basin from north to south after the Oligocene/Miocene sea-level fall. The sampled interval around the Oligocene/Miocene boundary contains a lot of reworked Paleogene (including irregular upper Oligocene species occurrences) and Mesozoic taxa, which explains why the Miocene strata in the ON-Mol-1 and Weelde boreholes were dated as Chattian by previous studies.
Elaboração e aplicação de um jogo didático para o ensino de ligações químicas: uma intervenção da residência pedagógica.
Authors: Nepomuceno Ferreira Samuel , Wilson Vicente de Assis Marcos , Dos Santos Niculau Edenilson , Augusto Barra de Oliveira Daniel
Published: July 2020

Para este dossiê temático não há necessidade de resumo.
MIOPATIA INFLAMATÓRIA IDIOPÁTICA
Authors: Snovarski Mota Luciana , Brito Gonçalves Caio Willer , Bastos Alves Junior Dilomá , Snovarski Mota Fernanda , Marques Silveira Janne , Lemos de Brito Andréia Kássia , Urzêdo Ribeiro Letícia
Published: July 2020

A dermatomiosite é uma doença rara caracterizada por fraqueza muscular progressiva e simétrica das cinturas escapular e pélvica proximais, que pode apresentar alterações dermatológicas características como heliotropo e/ou Sinal de Grotton, além de acometimento sistêmico cardiopulmonar, gastrointestinal e articular. Relata-se o caso de um paciente R.L.A.F., 41 anos, masculino, autodeclarado branco, casado, natural de Riachão – MA, residente e procedente de Formoso do Araguaia – TO e deu entrada no Hospital Geral Público de Palmas (HGPP). Durante avaliação inicial realizada pela equipe de reumatologia, foram observadas alterações importantes e características por meio de anamnese e exame físico com evolução de cerca de 1 ano e intensificação 3 meses antes da internação hospitalar. O paciente apresentava-se aparentemente emagrecido, com fácies hipocrática, queixa importante de disfagia e perda nítida da força muscular durante avaliação. Foram solicitados exames específicos e complementares a fim de descartar diagnósticos diferenciais e associação neoplásica. Diante do quadro clínico compatível, iniciou-se profilaxia para estrongiloides e tratamento com metilprednisolona 1g/dia por três dias consecutivos, e consequente aos três dias de pulsoterapia, realizada prednisona 60 mg/dia associada a metotrexato 15mg uma vez por semana e ácido fólico 5 mg duas vezes por semana, além de acompanhamento multidisciplinar. Devido a melhora substancial após tratamento hospitalar instituído, paciente recebeu alta hospitalar com acompanhamento ambulatorial especializado. Considerando que a doença é rara, de difícil diagnóstico, faz se importante relatar o caso deste paciente.
OTIMIZAÇÃO DA DESIDRATAÇÃO OSMÓTICA E SECAGEM DA PIMENTA MALAGUETA (Capsicum frutescens)
Authors: Marques Tenório Pereira Cecília , Matos Silva Sousa Hermanny , Gomes Alves Denise , Gramacho da Silva Warley
Published: July 2020

A pimenta malagueta (Capsicum frutescens) é bastante apreciada, não apenas pela sua importância econômica, mas também ao seu rico valor nutricional. Uma alternativa para aumentar a vida útil dos alimentos poderia ser a utilização de métodos de desidratação. A metodologia de superfície de resposta consiste numa ferramenta matemática e estatística que consegue avaliar simultaneamente a influência de diferentes fatores, as estruturas de redes neurais artificiais tem-se a solução de diversos tipos de problemas O objetivo deste trabalho é Otimização do tratamento osmótico da pimenta malagueta fazendo uso das técnicas de Metodologia de Superfície de Resposta e Redes Neurais Artificiais. No processo de desidratação osmótico o planejamento experimental utilizado foi o fatorial completo 23 com 1 ponto central e 6 pontos axiais totalizando 15 experimentos. A secagem convencional foi realizada após a escolha das melhores condições de desidratação osmótica a partir do gráfico de desejabilidade. Utilizando as melhores condições de desidratação osmóticas, as amostras em seguida foram colocadas em estufa nas temperaturas para proceder a análise da cinética de secagem. O processo de desidratação foi eficiente para as variáveis de resposta de PA, GS e IED para as duas soluções desidratantes ainda que não apresentassem efeito significativo.
Perbandingan Estimasi Metode Kuadrat Terkecil Terboboti dan Metode Transformasi Box-Cox Pada Data Heteroskedastisitas
Authors: Risma Risma , Sahriman Sitti
Published: July 2020

Dalam mengestimasikan parameter regresi umumnya digunakan metode kuadrat terkecil. Metode ini memiliki beberapa asumsi yang perlu dipenuhi salah satunya yakni homoskedastisitas. Pelanggaran asumsi homoskedastisitas dapat menyebabkan model estimasi tidak efisien. Oleh karena itu jika terjadi pelanggaran homoskedastisitas maka metode kuadrat terkecil tidak dapat lagi digunakan,sehingga diperukan metode alternative. Metode untuk mengatasi pelanggaran homoskedatisitas dua diantaranya yakni  metode kuadrat terkecil terboboti dan metode transformasi Box-Cox. Dalam penelitian ini akan dibandingkan metode kuadrat terkecil terboboti dan metode transformasi Box-Cox. Dari penerapan kedua metode tersebut didapatkan metode kuadrat terkecil terboboti memiliki RMSE (root mean square error) yang lebih kecil dan R2 yang lebih besar dibandingkan metode transformasi Box-Cox. Maka dapat disimpulkan metode kuadrat terkecil terboboti lebih bagus digunakan dalam menangani pelanggaran homoskedastisitas.
Estimasi Model Regresi Kuantil Spline Kuadratik pada Data Trombosit dan Hematokrit Pasien DBD
Authors: Aprilia Bunga , Islamiyati Anna , Anisa Anisa
Published: July 2020

Nonparametric quantile regression is used to estimate the regression function when assumptions about the shape of the regression curve are unknown. It is only assumed to be subtle by involving quantile values. One estimator in nonparametric regression is spline. The segmented properties of the spline provide more flexibility than ordinary polynomials. Therefore, the nature of the spline makes it possible to adapt more effectively to the local characteristics of a function or data. This study proposes to get the results of the estimation platelet count model to the hematocrit value of DHF. The optimal model obtained from the estimation of quadratic spline quantile regression is at quantile 0.5 with one knot and the GCV value is 41.5. The results of the estimation show that there is a decrease in platelet counts as the percentage of hematocrit increase.
Estimasi Parameter Model Poisson Hidden Markov Pada Data Banyaknya Kedatangan Klaim Asuransi Jiwa
Authors: Koerniawan Vieri , Sunusi Nurtiti , Raupong Raupong
Published: July 2020

The Poisson hidden Markov model is a model that consists of two parts. The first part is the cause of events that are hidden or cannot be observed directly and form a Markov chain, while the second part is the process of observation or observable parts that depend on the cause of the event and following the Poisson distribution. The Poisson hidden Markov model parameters are estimated using the Maximum Likelihood Estimator (MLE). But it is difficult to find analytical solutions from the ln-likelihood function. Therefore, the Expectation Maximization (EM) algorithm is used to obtain its numerical solutions which are then applied to life insurance data. The best model is obtained with 2 states or m = 2 based on the smallest Bayesian Information Criterion (BIC) value of 338,778 and the average predicted number of claims arrivals is 0.385 per day.
Pemodelan Regresi Logistik Menggunakan Metode Momen Diperumum
Authors: Yusuf Grace Oktavia , Jaya Andi Kresna , Ilyas Nirwan
Published: July 2020

Regresi logistik merupakan model regresi yang sering digunakan dalam pemodelan data kategori, namun dalam menentukan modelnya terkadang tidak dapat diselesaikan dengan cara biasa dikarenakan variabel respon yang bersifat kategorikal mengikuti distribusi bernoulli. Sehingga dalam menentukan model diperlukan suatu estimasi parameter untuk  mendapatkan informasi mengenai parameter populasi. Metode momen diperumum (Generalized method of moments/GMM) adalah salah satu metode estimasi parameter yang digunakan untuk mengeksploitasi informasi bentuk kondisi momen populasi yang merupakan perluasan dari metode momen. Dari penggunaan estimasi parameter GMM diperoleh bahwa dengan menggunakan kondisi momen yang sama dengan metode momen pada umumnya menghasilkan estimasi yang sama dengan metode momen ataupun dengan estimasi OLS. Dalam mengestimasi parameter regresi logistik pun diperlukan suatu algoritma untuk menyelesaikan bentuk nonlinear-nya, sehingga digunakan iterasi Reweighted least square yang pembobotnya berubah setiap pengiterasian.Kata Kunci: Regresi Logistik Biner, Metode Momen Diperumum, Iterasi Reweighted Least Square.Regresi logistik merupakan model regresi yang sering digunakan dalam pemodelan data kategori, namun dalam menentukan modelnya terkadang tidak dapat diselesaikan dengan cara biasa dikarenakan variabel respon yang bersifat kategorikal mengikuti distribusi bernoulli. Sehingga dalam menentukan model diperlukan suatu estimasi parameter untuk  mendapatkan informasi mengenai parameter populasi. Metode momen diperumum (Generalized method of moments/GMM) adalah salah satu metode estimasi parameter yang digunakan untuk mengeksploitasi informasi bentuk kondisi momen populasi yang merupakan perluasan dari metode momen. Dari penggunaan estimasi parameter GMM diperoleh bahwa dengan menggunakan kondisi momen yang sama dengan metode momen pada umumnya menghasilkan estimasi yang sama dengan metode momen ataupun dengan estimasi OLS. Dalam mengestimasi parameter regresi logistik pun diperlukan suatu algoritma untuk menyelesaikan bentuk nonlinear-nya, sehingga digunakan iterasi Reweighted least square yang pembobotnya berubah setiap pengiterasian. Kata Kunci: Regresi Logistik Biner, Metode Momen Diperumum, Iterasi Reweighted Least Square.
Special Issue on Laser-Based/Assisted Manufacturing
Authors: Kuriyagawa Tsunemoto , Mizutani Masayoshi
Published: July 2020

The “process chain” concept for the integration of multiple manufacturing processes has been attracting attention in the field of manufacturing in recent years. In a number of specialized fields, laser-based processes in particular are actively being studied, as their high flexibility allows them to be used not only as individual manufacturing processes but also in combination to develop new ones.

Most of the practical laser technologies involve heat, which can be used for thermal processing to change surface properties or for removal processing. In recent years, lasers have also been used as a heat source for additive manufacturing, as well as ultra-short-pulsed lasers being applied to non-thermal processes.

This special issue features various studies and reports that present the latest advances as well as current challenges in laser-based/assisted manufacturing. It includes nine related papers that indicate the possibilities and future of new laser processing technologies.

We deeply appreciate all the authors and reviewers for their efforts and contributions, and we also hope this special issue will encourage further research on laser-based/assisted manufacturing.
Processing with Application of High-Power Semiconductor Laser – Theoretical Analysis of Heat Source and Application to Surface Processing –
Authors: Arai Takeji ,   Research and Development Initiative, Chuo University 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
Published: July 2020

Since the semiconductor laser has a high conversion efficiency, it has many expectations for effective application. There are increasing application trials of processing at actual factories and jobsites. Moreover, it can currently be used as a heat source to directly conduct processing. This is called direct-diode laser (DDL). However, since there is almost no information regarding the DDL structure and beam mode, there are no scientific documents for the theoretical treatment of this heat source. This is considered to have interfered with the broad application for development. This research establishes the theoretical analysis of the semiconductor heat source for material processing, and we attempted to employ a simulation for processing. To verify the established theory, surface hardening and welding processing were performed as typical processing.
Fabrication of a Two-Dimensional Diffraction Grating with Isolated Photoresist Pattern Structures
Authors: Matsukuma Hiraku ,   Department of Finemechanics, Tohoku University 6-6-01 Aramaki Aza-Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan, Matsunaga Masanori , Zhang Kai , Shimizu Yuki , Gao Wei
Published: July 2020

This paper presents a fabrication method of a two-dimensional (2D) diffraction grating with isolated photoresist pattern structures in order to reduce fluctuation in the grating pitch due to the thermal expansion. At first, theoretical calculations for the fabrication of a 2D diffraction grating with isolated photoresist pattern structures are carried out to estimate the influences of exposure and development time on the pattern structures to be fabricated through the pattern exposure and development process. A diode laser-based compact non-orthogonal two-axis Lloyd’s mirror interferometer system designed in a size of 500 mm × 840 mm is then built on a breadboard for stable mask-less interference lithography. Basic performances of the newly developed compact interferometer system are evaluated through the fabrication of 2D diffraction gratings to demonstrate the feasibility of the theoretical calculations and the developed lithography system.
Effects of Pulse Duration and Heat on Laser-Induced Periodic Surface Structures
Authors: Kodama Shuhei , Shimada Keita , Mizutani Masayoshi , Kuriyagawa Tsunemoto ,   Tokyo University of Agriculture and Technology 2-24-16 Nakacho, Koganei, Tokyo 184-0012, Japan,   Tohoku University, Sendai, Japan
Published: July 2020

Compared with traditional nanotexturing methods, an ultrashort-pulsed laser is an efficient technology of fabricating nanostructures called laser-induced periodic surface structures (LIPSS) on material surfaces. LIPSS are easily fabricated when the pulse duration is shorter than collisional relaxation time (CRT). Accordingly, ultrashort-pulsed lasers have been mainly used to study LIPSS, but they unstably irradiate while requiring high costs. Although long-pulsed lasers have low cost and high stability, the phenomena (such as the effect of pulse duration, laser wavelength, and heat) of the LIPSS fabricated using short-pulsed lasers with the pulse duration close to the maximum CRT, which is greater than femtosecond, have not been clarified. However, the nanosecond pulse laser has been reported to produce LIPSS, but those were unclear and ununiform. In this study, the short-pulsed laser with the pulse duration of 20 ps, which is close to the maximum CRT, was employed to clarify the effects of pulse duration and heat on the fabrication of LIPSS and to solve problems associated with ultrashort-pulsed lasers. First, a finite-difference time-domain simulation was developed at 20-ps pulse duration to investigate the effects of irradiation conditions on the electric-field-intensity distribution. Subsequently, experiments were conducted using the 20-ps pulse laser by varying conditions. The aspect ratio of the LIPSS obtained was greater than that of the LIPSS fabricated using ultrashort-pulsed lasers, but LIPSS were not fabricated at 355- and 266-nm laser wavelength. In addition, the short-pulsed laser experienced thermal influences and a cooling material was effective for the fabrication of LIPSS with high-aspect-ratio. This demonstrates the effects of pulse duration close to the CRT and heat on the fabrication of LIPSS.
A Novel Platform for Smart 3D Manufacturing System
Authors: Melis Gianluca , Sirianni Paolo , Porceddu Andrea , Messere Massimiliano , Perlo Michele , Orbech Luca , Mauro Stefano , Gaidano Matteo , Scimmi Leonardo Sabatino , Melchiorre Matteo , Perrucci Francesco , Scaltrito Luciano ,   Department of Applied Science and Technology, Polytechnic University of Turin  Corso Duca degli Abruzzi, 24, Turin 10129, Italy,   Microla Optoelectronics S.r.l., Chivasso, Italy,   Cemas Elettra S.r.l., Carmagnola, Italy,   Department of Mechanical and Aerospace Engineering, Polytechnic University of Turin, Turin, Italy
Published: July 2020

The proposed paper is about the development of an integrated manufacturing process for smart 3D polymeric components, with electronics embedded, developed in the framework of research collaboration between the university partner and a group of SME. The system will be able to produce a polymeric structure by additive manufacturing technique, whereas a robotic system is integrated in the line to assemble electronic components onto the part while the manufacturing process goes on. A laser engraving station will process the component, providing micro- and nano-surface structuring, microcutting and microdrilling. Finally, another laser source is integrated in the system to weld electronic parts and circuits within the manufactured component. At the same time, the assembly of large size systems by welding small size components is allowed, and also a sealed atmosphere is ensured by welding a plastic cap onto the plastic structure.
Evolution of Chip-Deformation Mechanisms with Increasing Temperature in Laser-Assisted Microcutting of Amorphous Alloy
Authors: Gong Qingrui ,   Department of Mechanical and Energy Engineering, Southern University of Science and Technology 1088 Xueyuan Avenue, Shenzhen 518055, China, Qiu Pei , Xu Shaolin
Published: July 2020

NiP coating with an amorphous structure is a commonly used mold material for manufacturing resin optical components. However, due to the inhomogeneous deformation characteristics of amorphous alloys, chippings and burrs are easily produced at the edge of microstructures. Laser-assisted microcutting has proven to effectively inhibit the generation of these defects but the evolution of chip-deformation mechanisms with different laser power remains to be explored. In this study, a simulation of the temperature field under nanosecond laser irradiation was conducted and the laser-assisted cutting of NiP was considered, using the same irradiation parameters. Through the analysis of chip morphology under different conditions, it is found that the temperature in the deformation zone mainly affects the morphology of the secondary shear bands but has no effect on the number of nucleation in the primary and secondary shear bands. The proper temperature in the shear deformation zone can improve the deformation ability of the secondary shear band, thus making the shearing process more stable. This research will prove helpful to understand the material deformation mechanisms to guide the selection of laser parameters in the laser assisted cutting of amorphous alloy.
Generation of Biocompatible Titanium Alloy Surfaces Including Calcium and Phosphorus Elements by Laser-Induced Mist Spraying Wet Treatment
Authors: Ezura Atsushi , Katahira Kazutoshi , Komotori Jun ,   Industrial Technology Center of Tochigi Prefecture 1-5-20 Yuinomori, Utsunomiya, Tochigi 321-3226, Japan,   RIKEN, Wako, Japan,   Keio University, Yokohama, Japan
Published: July 2020

Titanium alloys are widely used for the hard tissue substitute implants. However, it is necessary to improve interfacial biocompatibility to reduce adhesion period. For improvement of biocompatibility of Ti-6Al-4V ELI alloys, texture and chemical composition on contact part with biological tissue play very important roles. In this research, micro texture was generated on the Ti-6Al-4V ELI alloy surfaces utilizing laser irradiation, in order to improve biocompatibility. The biocompatibility was evaluated by osteoblast cell culture assays. The results indicated the surface having micro texture improve biocompatibility as compared with untreated surface. This was considered in order the fact that the formed modified surface had hydrophilicity, thereby improving the cell compatibility, and the cell adhesion due to the complicated shape. In addition, mist of glycerophosphoric acid calcium aqueous solution was applied on the laser irradiated area. As result, micro texture including Ca and P elements was generated on the Ti-6Al-4V ELI alloy surfaces. When laser was irradiated, glycerophosphoric acid calcium aqueous solution was applied as mist flowed on the test pieces as droplet. The velocity of droplet fluid was relatively fast, so that laser irradiation was unhindered access to the surface of test pieces and the treatment was stable. In order to estimate biocompatibility, culture assays using osteoblast cells were conducted on the treated surface having micro texture including Ca and P elements. As results, it was clearly that biocompatibility of the specimen treated by laser with glycerophosphoric acid calcium aqueous solution mist more improved than either untreated specimen or treated specimen soaked in glycerophosphoric acid calcium aqueous solution.
Study on the Creation of Fine Periodic Structure on V-Shaped Groove with Short-Pulsed Laser
Authors: Takase Ryohei , Kodama Shuhei , Shimada Keita , Mescheder Holger , Winands Kai , Riepe Jan , Arntz Kristian , Mizutani Masayoshi , Kuriyagawa Tsunemoto ,   Department of Mechanical Systems Engineering, Graduate School of Engineering, Tohoku University 6-6-01 Aramaki Aza-Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan,   Department of Mechanical System Engineering, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan,   Department of Non-conventional Manufacturing Processes and Technology Integration, Fraunhofer Institute for Production Technology IPT, Aachen, Germany,   Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan
Published: July 2020

Functional surface creation technologies have garnered increasing attention over the years. These technologies can provide various functions to a material by establishing a fine structure on the material surface and responding to the needs of industrial products with distinguished functions or high values. In addition, by creating a “composite fine structure,” which is composed of two kinds of structures with different scales, the enhancement of functions and emergence of new functionalities can be expected. Hence, our study combined a micrometer-scale V-shaped groove structure using an ultra-precision cutting and nanometer-scale ultra-fine periodic structure (LIPSS) using a short-pulsed laser. Then, we clarified the creation principle and studied the functionality of the structure, specifically, its wettability. As a result, it was found that optical behavior inside the V-shaped groove changed; therefore, the composite structure changed depending on the groove angle, laser polarization direction, and number of times of irradiation. In addition, it was found that the water wettability changed depending on the type of formed micro-nano composite structures. Moreover, the wettability could be controlled by depending on how the structure is used.
Hydraulic Micro Device with Force Sensing for Measurement of Mechanical Characteristics
Authors: Sasaki Tohru , Fujiwara Yudai , Tachikawa Kaoru , Terabayashi Kenji , Dohda Kuniaki ,   Department of Mechanical and Intellectual Systems Engineering, University of Toyama 3190 Gofuku, Toyama-shi, Toyama 930-8555, Japan,   Graduate School of Science and Engineering for Education, University of Toyama, Toyama, Japan,   Department of Mechanical Engineering, Northwestern University, Illinois, USA
Published: July 2020

The medical and bio-engineering fields have been increasingly using information and communication technology. To introduce robots into surgical procedures, data on surgical operations are required. Several studies have tried the creation of data on living tissues for mechanical actions, which makes determining the mechanical characteristics of living tissues vital, but few have been commonly used. Therefore, we previously developed a sensing system that uses a hydraulic-driven micro mechanism to measure the force applied to an object when it is touched. Micro force sensors are necessary for various manipulations requiring careful operation. Unfortunately, the measurement accuracy of sensors tends to reduce with the reduction in sensor size. The proportional output in conventional force sensors, such as piezoelectric sensors, also decreases when the size of the sensor is reduced. However, a micro force sensor using a hydraulic-driven micro mechanism can obtain a large output even when it is small. Our system uses Pascal’s principle to measure small forces acting on the end effector. We propose methods for identifying the mechanical characteristics of certain viscoelastic materials similar to those used in a living organ. A hydraulic-driven micro device pushes an object and measures the reaction force and its displacement. We have used two types of micro devices, micro cylinder and micro bellows. Its stiffness and viscosity coefficient are obtained through calculations using Kelvin-Voigt and Zenner models. Discrete displacement and load data are applied to the estimated model, and the mechanical characteristics of the materials are identified as a minimized value between the estimated value and experimental one. We conducted experiments using the proposed identification methods on viscoelastic materials, and the results indicate that the value provided from the Kelvin-Voigt model was near the truth value.
Measurement and Compensation of Tool Contour Error Using White Light Interferometry for Ultra-Precision Diamond Turning of Freeform Surfaces
Authors: Nagayama Kodai ,   Department of Mechanical Engineering, Faculty of Science and Technology, Keio University 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan, Yan Jiwang
Published: July 2020

In ultra-precision diamond turning of freeform optics, it is necessary to obtain submicron-level form accuracy with high efficiency. In this study, we proposed a new method for the quick measurement and compensation of tool contour errors to improve the form accuracy of the workpiece. In this method, the nanometer-scale contour error of a diamond tool is quickly and precisely measured using a white light interferometer and then compensated for, before machining. Results showed that the contour of a diamond tool was measured with an error less than 0.05 μm peak-to-valley (P-V) and the feasibility of error compensation was verified through cutting experiments to create a paraboloid mirror and a microlens array. The form error decreased to 0.2 μm P-V regardless of the contour error of the diamond tools when cutting the paraboloid mirror, and that of the microlens array was reduced to 0.15 μm P-V during a single machining step.
The Development of Blended Learning Model using Edmodo to Train Student Critical Thinking Skills on Impulse-Momentum Topic
Authors: Denny Yus Rama , Utami Indri Sari , Rohanah Siti , Muliyati Dewi
Published: July 2020

This study aims to determine the effect of developing blended learning models on students' critical thinking skills on impulse and momentum. The research method used in this study is ADDIE. The population in this study is class X MIA SMAN 4 Serang City. The sample of this study amounted to 31 students from class X MIA 2 as an experimental class using a blended learning model and 30 students from class X MIA 3 as a control class using a cooperative model. The test used in this study was eight essays in the form of representatives of one question indicator. These results indicate an increase in students' critical thinking skills after being given treatment that is by using a blended learning model. A large increase is evidenced by the N-Gain value in the experimental class that is 0.60 in the medium category and 0.23 in the low category in the control class. The average value of pretest and posttest is 5.27 and 9.77 in the control class, while in the experimental class is 5.65 and 16.61. These results show that there is an influence on the development of blended learning models for critical thinking skills on the momentum and impulses.
Examining the Women Issues and Child Abuse as Mirrored by Arundhati Roy’s The God of Small Things
Authors: Suleman Danish , Mohamed Abdul Halim
Published: July 2020

According to many reports, abuse of women and child is the biggest human rights violation in India. In this qualitative research paper, we are going to examine the causes that lead to women issues and child abuse in India from the perspective of Arundhati Roy’s novel The God of Small Things. In present India, even after its Independence, gender-discrimination and child abuse in Indian society are at worst. In order to understand the causes and reason that creates challenges for women and danger for children in Indian society, we will study the views and experiences of Arundhati Roy as she presented in her selected novel. we will be using a qualitative research methodology to analyze and collect the relevant data using the textual analysis method.  For this minor research, we will read and analyze the novel written by Arundhati Roy namely, The God of Small Things (1997). At the end of this study, we will reveal the position of these issues and causes for the women’s issues and child abuse issues. The significance of this study is to create an awareness among the readers on the importance of rights and freedom of women and children in India. This paper depicts how Indian women, as well as children, are facing problems and violence in their daily lives and how we used literature (novel) education to raise and build their personalities in order to contribute fruitfully in Indian society.
Assistance on Writing Scientific Papers for Students of Nusaniwe Village
Authors: Touwely Godprit Haris , Dandirwalu Resa , Laisila Maya , Nanuru Ricardo Freedom
Published: July 2020

Nusaniwe Student Association (IKAMAPENUSA) in Ambon City is an organization formed on the initiative of several educational figures from Negeri Nusaniwe (in Ambon City; the village is referred to as Negeri) with the aim of helping to develop the role of students in developing themselves, both in terms of academics and organizations. Observing the dynamics of plagiarism among students, the Stimulus Community Partnership Program (PKMS) team from Indonesia Christian University (UKIM) of Maluku, Ambon, took the initiative to approach IKAMAPENUSA to discuss issues related to their assignments as students. From the results of the discussion, it appears that there are a lot of problems they face, for example: (1) Lack of direction from teachers and lecturers related to the tasks assigned; (2) Lack of knowledge on how to look for good, well-categorized scientific literature; (3) lack of mastery of paraphrasing techniques; (4) lack of mastery of scientific writing techniques required by universities and schools; (5) Lack of mastery of technology related to quotations and bibliography such as Mendeley. The output of this activity has been published in Mimbar Rakyat News electronic mass media (http://mimbarrakyatnews.com/tim-pkms-ukim-gelar-penulisan-karya-ilmiah-bebas-plagiat-2/), and the video of activities has been uploaded to YouTube channel of UKIM TV (https://www.youtube.com/watch?v=tg-Cqn0-zao).