bluuebunny/crossref_metadata_2025 huggingface dataset:
Pemanfaatan Silika (SiO2) dan Bentonit sebagai Adsorben Logam Berat Fe pada Limbah Batik
Authors: Hardyanti Ika Sri , Nurani Isni , Hardjono HP Dyan Septyaningsih , Apriliani Evalisa , Wibowo Emas Agus Prastyo
Published: October 2018

Industri batik merupakan industri yang potensial dari proses awal hingga proses penyempurnaan diindikasikan penggunaan bahan kimia yang mengandung unsur logam berat. Hasil buangan limbah batik masih mengandung logam berat salah satunya Fe.Kandungan Fe yang tinggi dalam air limbah dapat mencemari lingkungan perairan apabila dibuang ke sungai atau saluran irigasi. Proses adsorpsi merupakan teknik pemurnian dan pemisahan yang efektif dipakai dalam industri untuk mengurangi ion logam berat dalam air limbah. Silika memiliki gugus aktif Si-O-Si dan Si-OH yang dapat digunakan sebagai adsorben logam Fe. Silika bersifat inert, mempunyai sifat adsorpsi dan pertukaran ion yang baik, mudah dimodifikasi dengan senyawa kimia tertentu, kestabilan mekanik dan termal tinggi, serta dapat digunakan untuk prekonsentrasi atau pemisahan analit karena proses pengikatan analit pada permukaan silika bersifat reversible. Telah dilakukan penelitian untuk mengetahui waktu pengadukan yang optimal pada adsorben silika dalam mengadsorpsi logam Fe yang terkandung dalam limbah batik desa Sudagaran, Banyumas.Terdapat empat sampel yang diuji dengan metode AAS masing-masing volumenya 400 mL dan berwarna coklat kemerahan. Sampel 1 belum dilakukan adsorpsi silika atau sebagai kontrol. Sampel 2, 3, dan 4 diadsorpsi silika dengan massa yang sama namun diberi perlakuan variasi waktu. Sampel 2, 3, dan 4 diaduk dengan variasi waktu berturut-turut 20, 40, dan 60 menit. Hasil penelitian menunjukkan bahwa waktu pengadukan 40 menit merupakan waktu yang optimal untuk silika dalam mengadsorbsi logam Fe. Terjadi penurunan kadar Fe dari 0,287 ppm menjadi 0,145 ppm. Sedangkan dengan bentonit terjadi penurunan kadar Fe dari 0,939 ppm menjadi 0,912 ppm. Kata kunci: logam berat, limbah batik, adsorpsi
Simulasi Kontrol 2 Pompa Supplay Air Bersih Menggunakanrelay Change Over Dan Floatless Level Switch (Sebagai Modul Praktek Mahasiswa Ps Teknik Pendingin Dan Tata Udara)
Authors: Sudirman Sudirman , Baliarta I Nyoman Gede
Published: October 2018

Sistem supplay air bersih pasti ada dipasang disuatu gedung. Tujuan dari penelitian ini adalah untuk menciptakan modul praktek mahasiswa Program Studi Teknik Pendingin  dalam mata Kuliah Praktek Utility Gedung dan BAS. Sehingga kompetensi mahasiswa tentang utility gedung, khususnya dibidang system pompa supplai air bersih bisa tercapai dengan lebih mudah. Modul praktek ini menggunakan 2 buah pompa, 2 buah tangki air, 1 sebagai tangki sebagai tangki underground tank dan 1 lagi sebagai tower tank. Menggunakan WLC (water level control) untuk mengontrol hidup mati pompa berdasarkan level  air pada tangki tower. Dan menggunakan Relay Change over untuk merubah pompa on duty secara otomatis. Hasil uji kerja alat simulasi ini, saat level air pada tangki tower low level, Pompa 1 akan hidup sampai level air mencapai upper level dan akan Off, secara otomatis Relay change over merubah pompa on duty dari Pompa 1 ke Pompa 2. Pada saat level air mencapai low level lagi di tangki tower, yang hidup adalah Pompa 2.
Perhitungan Lampu Penerangan Jalan Berbasis Solar System
Authors: Anhar Wahyu , Basri Basri , Amin Mohamad , Randis Randis , Sulistyo Totok
Published: October 2018

Artikel ini disusun berdasarkan kegiatan pengabdian kepada masyarakat (PKM) yang pernah dilakukan di Pondok Pesantren Darun Nafi KM.34 Samboja Kabupaten Kutai Kartanegara. Kegiatan PKM yang dilakukan adalah pemasangan lampu penerangan jalan berbasis solar system. Proses perhitungan dan pengujian lampu penerangan jalan berbasis solar system akan dibahas di dalam artikel ini. Lampu penerangan jalan menggunakan lampu dc 12 Volt, panel surya 50 Wp, charge control 10 A, dan battery 65 Ah. Lampu penerangan jalan digunakan selama 12 jam.
ANALISIS KEPUASAN DAN LOYALITAS KONSUMEN KOPI AAA DI KABUPATEN KERINCI
Authors: Pradinata Jahyu
Published: October 2018

Research objectives are to analyze the level of satisfaction of consumers against products of coffee powder Nefo Cap AAA. for consumer loyalty towards mengetahuitingkat ground coffee products Nefo Cap AAA. A sample of these studies amounted to 131 consumers Coffee Nefo Cap Regency AAA Kerinci. The data from this study are obtained from the results of a questionnaire distributed to respondents. This research was analyzed using the methods of Customer Satisfaction Index (CSI), the Importance of Performance Analisys (IPA). The results of this study found that the image of the pyramid Coffee loyalty Nefo Cap AAA in General can be said already quite well. On the level Switcher/Price Buyer has a considerable percentage of the amount that is 57 percent. This can lead to a reduced number of sales in the future due to the consumer at this level are likely to be moved on the ground coffee brand to another if there is a manufacturer that sells ground coffee that is cheaper with the same quality with the brand of coffee Nefo Cap AAA. At the level of the respondent which is brand loyalitas Switcher of 57%, respondents who Hobitual of 69%, of respondents which is a Satisfied Buyer of 70%, of the respondents which is Liking the Brand of 68%, and respondent who is a Committed Buyer of 68%.
Effects of operating parameters of the NSV system on soilcrete characteristics in the Mekong Delta
Authors: Truong Chau Dac , Tran Hung Nguyen Hoang , Nguyen Tien Binh , Mai Phuong Anh
Published: October 2018

Unconfined compressive strength (UCS) and uniformity of soilcrete are strongly influenced by deep mixing equipment and its operating parameters. Soilc cement mixing was applied to reinforce the two sections of earth levees (1) 60 m long in An Giang and (2) 30 m long in Dong Thap using the NSV system. Core boring was employed to take field soilcrete samples and UCS tests were conducted to investigate soilcrete characteristics. The results indicate that the field soilcrete achieved high UCS and uniformity along soilcrete columns with blade rotations of 650 times/m, mixing time of 2.5-3.5 minutes/m, rod rotations of 40-50 times/m (penetration) and 70-80 times/m (lift), penetrating speed of 0.5 m/minute and lifting speed of 1.2 m/minute
The measuring scales of “personal values” in the Vietnamese market with model of consumer behavior in services
Authors: Nguyen Thuy Thu
Published: October 2018

The research provides an overview of theories related to the concept of “personal values” and the formation and development of the measuring scales of “personal values” in the world. Based on the findings that the current measuring scale is inappropriate in the Vietnam society, the writer calibrated all indicators of the used scale and constructed a new measuring scale which well match the context of the market research. The results showed that “personal values” in the Vietnamese market includes five elements, which are (i) peaceful life; (ii) love; (iii) self-esteem; (iv) social integration; and (v) social recognition. The author then implements the accreditation of the research of the individual value measurement in the Vietnam market with the model of service consumer behaviour (tourism and passenger transportation services). The result shows that the measuring scales well match the context of the market research. However, each type of service has its different expression. In particular, (i) five elements of measurement have different important levels in each service sector. (ii) the effect of the “personal values” on target variable (attitude) also has different intensities between two different sectors.
Study on the antibacterial activities of Hibiscus rosa-sinensis leaf extracts against Staphylococcus aureus and Klebsiella pneumoniae
Authors: Luong Ngan Thi My , Nguyen Linh Thi Thuy , Nguyen Quy Ngoc , Pham Huyen Thi Ngoc , Truong Hoa Thi Huynh , Tran Hieu Trung , Pham Ho Thanh
Published: October 2018

Hibiscus rosa-sinensis has been used in folk medicine to treat inflammation and bacterial infections for a long time. This study aims to evaluate the antibacterial activity of H. rosa- sinensis leaf extracts against Staphylococcus aureus and Klebsiella pneumoniae. Both are the major causes of hospital acquired infections. The results showed that the hexane and ethyl acetate fractions were similarly active to S. aureus but very weak active to K. pneumoniae. Both of these fractions were subjected to chromatograph using silica gel column eluted with hexane and ethyl acetate, and yielded 24 hexane subfractions (H1–H24) and 25 ethyl acetate subfractions (E1–E25). All subfractions had no or little activities to K. pneumoniae. Subfractions as H4, H14–H16, and E1, E7, E17–E19 had strong activities against S. aureus. Especially, E7 subfraction exhibited the strongest activity with MIC and MBC values of 0.1 and 0.2 mg/mL, respectively. GC-MS data showed that the main constituents of the E7 subfraction were neophytadiene, trans-phytol and 3,7,11,15-tetramethyl-2-hexadecen-1-ol.
The relationship between SNP rs895819 (A>G) on miRNA-27a and the breast cancer in the Vietnamese population
Authors: Nguyen Phong Ba Hung , Tran Minh Thi Hong , Nguyen Thanh Thi Ngoc , Nguyen Hue Thi
Published: October 2018

Breast cancer (BC), the most common type of cancer among women worldwide, is a polygenetic disease which is caused by the interaction of several genes. Understanding the genetic factors for early diagnosis of BC is crucial to ensure the survival of BC patients. MicroRNA 27a (miR-27a), an oncogenic miRNA, has been predicted to target on the tumor suppressor ZBTB10 that can regulate many processes of cell. Single nucleotide polymorphism (SNP) rs895819 alters the structure and function of miR-27a, which has been anticipated to reduce the risk of BC in different populations such as German and Chinese. This study aimes to investigate the relationship between the existence of SNP rs895819 (A>G) and the risk of BC using the optimized high resolution melting (HRM) method. 106 BC samples and 117 healthy samples were genotyped using an optimal HRM protocol then statistical analysis was applied to examine the relationship of the SNP. In the case group, the risk G allele accounted for 36 % while in the control group it took up 32 %. Statistic result revealed that rs895819 (A>G) had no significant relationship with the breast cancer (OR=1.119; P=0.46676) in given case-control samples. Although the SNP is significantly ralated with BC in German or Chinese populations, it is not a potential marker for diagnosis in the Vietnamese population. Further studies investigating relationship between rs895819 (A>G) and breast cancer in the Vietnamese population is not recommended. In future, other SNPs should be investigated with the aim of identification efficient biomarker for early diagnosis of BC in Vietnamese.
An approximate Hahn-Banach-Lagrange theorem
Authors: Nguyen Dinh , Tran Mo Hong
Published: October 2018

In this paper, we proved a new extended version of the Hahn-Banach-Lagrange theorem that is valid in the absence of a qualification condition and is called an approximate Hahn-Banach-Lagrange theorem. This result, in special cases, gives rise to approximate sandwich and approximate Hahn-Banach theorems. These results extend the Hahn-Banach-Lagrange theorem, the sandwich theorem in [18], and the celebrated Hahn-Banach theorem. The mentioned results extend the original ones into two features: Firstly, they extend the original versions to the case with extended sublinear functions (i.e., the sublinear functions that possibly possess extended real values). Secondly, they are topological versions which held without any qualification condition. Next, we showed that our approximate Hahn-Banach-Lagrange theorem was actually equivalent to the asymptotic Farkas-type results that were established recently [10]. This result, together with the results [5, 16], give us a general picture on the equivalence of the Farkas lemma and the Hahn-Banach theorem, from the original version to their corresponding extensions and in either non-asymptotic or asymptotic forms.
Layered double hydroxides Cu-Al: Synthetic and catalytic applications in the alkylation reaction of indole with benzaldehydes
Authors: Nguyen Truc Hoang Thanh , Tran Phuong Hoang , Nguyen Chinh Quoc
Published: October 2018

Layered double hydroxides derived Cu-Al metal oxides were found to be an efficient catalytic reagent for the reaction of indole benzaldehydes. In this report, we prepared series of (Cu/Al)-CO3 layered double hydroxides with the unchanging ratio of Cu/Al = 3 : 1 and it was subsequently calcinated in air at 500 oC. The materials were characterized by means of Inductively Coupled Plasma emission (ICP), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and, thermogravimetry (TG). The materials were calcinated at 500 oC and tested as catalysts in the alkylation reaction of indole with benzaldehydes.
Erimtan Arkeoloji ve Sanat Müzesi Bizans Dönemi Maden Haçları
Authors: KOÇYİĞİT Oğuz
Published: October 2018

Bu çalışma kapsamında Erimtan Arkeoloji ve Sanat Müzesi koleksiyonunda yer alan ve oldukça iyi durumda olan toplam on bir adet maden haç ele alınmıştır. Ele alınan eserlerin yedisi röliker haç olup, ikisi tören / takdis haçı, diğer ikisi de kolye uçlarına asılan pandantif haçlardan oluşur. Ayrıca koleksiyonda yer alan haçlardan sadece biri demir, diğerleri bronzdur. Neredeyse tamamının Orta Bizans Dönemi’ne ait olduğunu söyleyebileceğimiz eserler üzerindeki süsleme ve bezeme özellikleri, bu eser grubunun niteliğini arttıran başlıca özelliktir. Nitekim, bronzdan yapılmış olan tören haçı ender rastlanan formu ile öne çıkarken, büyük olasılıkla takdis amaçlı kullanılmıştır. Demirden yapılmış olan tören haçı ise, üzerindeki altın yaldızlar ile oldukça önemli bir örnek olup, diğer eserlerden bu yönüyle ayrılır. Yine koleksiyonda yer alan rölikerler üzerindeki figür bezemeler ve kazıma süslemeler, bu eserleri nitelikli kılar. Yakın benzerlerinin çeşitli müze ve kolleksiyonlarda karşımıza çıkması ise Bizans Sanatı’nda oldukça sevilen bir sanatsal üslubu temsil ettiklerini gösterir.
A Cultural Materialist Approach to Gender Relations in Ibsen’s A Doll’s House
Authors: DÜZGÜN Şebnem
Published: October 2018

The Norwegian writer Henrik Ibsen’s A Doll’s House (1879) explores gender relations which were fiercely debated in the late nineteenth century. The play deals mainly with the oppression of a bourgeois woman named Nora, who forges her father’s signature to save her husband’s life. Regarded as a member of the inferior sex, Nora is dominated by her patriarchal-minded husband Helmer. As she lacks socio-economic freedom to earn her own money, she is forced to obey the will of her husband, who imprisons her in the domestic sphere where she is degraded as an ignorant, inferior being who needs intellectual and moral guidance. Moreover, Helmer manipulates his position as a wage earner and treats Nora as an object that is to be possessed and controlled. Since Helmer benefits from his ‘superiority’ in terms of his gender and economic position, he represents both a domineering patriarch and a manipulative capitalist master. However, Nora is not depicted as a passive receiver of male domination for she develops counter discourses against her husband’s patriarchal discourses which focus on the inferiority of the female sex. Frustrated with the dominant moral and legal discourses of patriarchy that despise women, Nora decides to move from the restrictive domestic world to the outside world of power, money, and business. Her removal from the domestic sphere where she is expected to perform certain normative roles associated with the female sex is important in that it heralds women’s emancipation from male domination. The present study examines A Doll’s House from a cultural materialist perspective to argue that Nora’s departure from her husband’s house is not only a personal experience but a social challenge against the dominant patriarchal capitalist culture.
Consideration of Passenger Interactions for the Prediction of Aircraft Boarding Time
Authors: Schultz Michael , Reitmann Stefan
Published: October 2018

In this paper we address the prediction of aircraft boarding using a machine learning approach. Reliable process predictions of aircraft turnaround are an important element to further increase the punctuality of airline operations. In this context, aircraft turnaround is mainly controlled by operational experts, but the critical aircraft boarding is driven by the passengers’ experience and willingness or ability to follow the proposed procedures. Thus, we used a developed complexity metric to evaluate the actual boarding progress and a machine learning approach to predict the final boarding time during running operations. A validated passenger boarding model is used to provide reliable aircraft status data, since no operational data are available today. These data are aggregated to a time-based complexity value and used as input for our recurrent neural network approach for predicting the boarding progress. In particular we use a Long Short-Term Memory model to learn the dynamical passenger behavior over time with regards to the given complexity metric.
Performance Assessment of Reynolds Stress and Eddy Viscosity Models on a Transitional DCA Compressor Blade
Authors: Vlahostergios Zinon
Published: October 2018

In the current work a detailed investigation and a performance assessment of two eddy viscosity and two Reynolds stress turbulence models for modelling the transitional flow on a double circular arc (DCA) compressor blade is presented. The investigation is focused on the comparison of the obtained computational results with available experimental data for a specific DCA compressor blade cascade which can be found in the European Research Community on Flow, Turbulence and Combustion (ERCOFTAC) experimental database. The examined flow field is very challenging for the performance assessment of the turbulence models. The blade inlet angle departs +5° from the compressor blade design conditions resulting in a complex flow field having large regions of boundary layer transition both on the suction and pressure sides of the blade with the presence of an unsteady wake. The presented results include velocity and turbulence intensity distributions along the pressure, the suction sides, and the wake region of the blade. From the comparison with the available experimental data, it is evident that in order to accurately compute such complex velocity and turbulence fields that are met in aero engine components (compressors and turbines), it is obligatory to use more advanced turbulence models with the Unsteady Reynolds Averaged Navier Stokes Equations (URANS) adoption, or other simulation and hybrid methodologies which require unsteady calculations.
Bamboo Biochar Pyrolyzed at Low Temperature Improves Tomato Plant Growth and Fruit Quality
Authors: Suthar Ratna G. , Wang Cun , Nunes M. Cecilia N. , Chen Jianjun , Sargent Steven A. , Bucklin Ray A. , Gao Bin
Published: October 2018

As a soil amendment, biochar can significantly improve soil quality and crop growth. Few studies, however, have explored biochar effects on crop quality. This study investigated the amendment effects of bamboo biochar pyrolyzed at different temperatures on plant growth and fruit quality of tomato (Solanum lycopersicum L.). Tomato ‘Micro-Tom’ plants were grown in a sand medium amended with 0, 1, and 3% of biochars produced at 300 °C, 450 °C, and 600 °C, respectively. Plant growth was monitored, and fruit harvested at the red stage was analyzed for color, texture, soluble solids content, sugars, ascorbic acid, and acidity. Results showed that biochars produced at 300 °C and amended at 3% or pyrolyzed at 450 °C and amended at 1% increased plant growth index. Contents of glucose, fructose, soluble solids, ascorbic acid, and sugar-to-acid ratios of fruits produced from the two treatments were significantly higher than the other treatments. The improved plant growth and fruit quality were related to the higher concentrations of NO3, P, Ca, and Mg in the growing media. Our results suggest that optimizing biochar use can be achieved by targeting biochar production conditions and application rate, which resulted in desirable amendment and fruit quality effects.
Growth, Yield Performance and Quality Parameters of Three Early Flowering Chia (Salvia hispanica L.) Genotypes Cultivated in Southwestern Germany
Authors: Grimes Samantha J. , Phillips Timothy D. , Hahn Volker , Capezzone Filippo , Graeff-Hönninger Simone
Published: October 2018

The combination of consumer’s ongoing demand for chia (Salvia hispanica L.) alongside the increased demand for regionally produced food products provided the impetus for this study. Its aim was to test if a regional cultivation of new chia genotypes, which were adapted to day lengths greater than 12 h, is feasible under Central European conditions. Therefore, three early flowering chia genotypes (Sahi Alba 914, W13.1, G8) were cultivated in a randomized block design at two experimental stations in Southwestern Germany (Ihinger Hof, Eckartsweier) over the course of two years (2015, 2016). Mean yields ranged from 100 to 1290 kg ha−1. Mucilage content ranged from 9.5% to 12.2%, while the crude protein content ranged from 17.2% to 25.0%. Crude oil content fell in the range of 30.9–33.7% and the PUFA:SAT ratio ranged from 4.0 to 9.4, whereas the omega6:omega3 ratio varied from 0.27 to 0.5. As chia seed yields surpassed yield levels obtained by their countries of origin and as quality parameters obtained, were in line with the genotypes cultivated in their countries of origin, it can be assumed that a regional chia production in Southwestern Germany offers great potential, being ecologically and economically profitable.
Proteomic Evaluation of Insecticidal Action of Phosphine on Green Peach Aphids, Myzus persicae
Authors: Kim Kyeongnam , Park Jeong Sun , Yang Jeong Oh , Lee Sung-Eun
Published: October 2018

Phosphine (PH3) fumigation is one of the best alternatives to methyl bromide for regulating insect pests during storage and shipping. Recently, this treatment has been applied to other agricultural insect pests, including Myzus persicae. To understand the mode of PH3 toxicity in M. persicae, proteomic analyses using liquid-chromatography tandem mass spectrometry were conducted to measure comparative protein expression levels between PH3-treated samples and controls. PH3 treatment increased NADH dehydrogenase (ubiquinone) flavoprotein 1, mitochondrial-like (complex I) expression, but decreased complex II and ATPases in the mitochondrial electron transport chain (ETC) of M. persicae. Glucosidase and antimicrobial proteins such as lysozymes showed enhanced expression in PH3-treated M. persicae. Some regulatory proteins related to apoptosis were more abundant in PH3-treated M. persicae. Biochemical activities of acetylcholinesterase (AChE) and cytochrome c oxidase (COX) were also measured because these enzymes are known to be targeted by PH3. Only COX activity decreased in relation to increasing PH3 concentrations in adult M. persicae. The expression of six selected genes were determined in relation to PH3 treatments. No two-fold changes in the expression of the six genes was observed. Thus, PH3 toxicity caused disruption in the ETC and glucose supply, as well as dis-regulation of apoptosis in M. persicae.
Frequency Sensitivity and Mode Characteristics of Body Structure for a Piezoelectric-Based UUV
Authors: Li Chong
Published: October 2018

The authors propose a novel unmanned underwater vehicle (UUV) based on a piezoelectric smart element, which facilitates piezoelectric energy harvesting as well as piezoelectric vibration reduction. In this report, the operating principle of the UUV is presented. Using Donnell’s theory, dynamic models of body structure are established, and the natural frequency sensitivity in addition to the vibration mode equations are deduced. Using MATLAB software, the vibration modes and their sensitivity to the change of investigated parameters are simulated. The results indicate that the natural frequencies are sensitive to the change of the middle surface radius and body length. It was also noted that the shear modes are more apparent for lower order vibrations, while the torsional moment modes are more significant for higher order vibrations. These results can be used both to optimize the dimensions of a UUV and to reduce its vibrations during operation.
Feasibility Study of Real-Time Monitoring of Pin Connection Wear Using Acoustic Emission
Authors: Wang Jingkai , Huo Linsheng , Liu Chunguang , Peng Yuanchen , Song Gangbing
Published: October 2018

Pin connections are one of the most important connecting forms and they have been widely used in engineering fields. In its service, pin connections are subject to wear, and it will be beneficial if the health condition of pin connections can be monitored in real time. In this paper, an acoustic emission (AE)-based method was developed to monitor wear degree of low rotational speed pin connections in real time in a nondestructive way. Most pin connections are operated at low rotational speed. To facilitate the research, an experimental apparatus to accelerate the wear test of low rotational speed pin connections was designed and fabricated. The piezoceramic AE sensor was mounted on the test apparatus in a nondestructive way, and it was capable of real-time monitoring. Accelerated wear tests of low rotational speed pin connections were conducted. To verify the results of the AE technique, a VHX-600E digital (from Keyence, Osaka, Japan) microscope was applied to observe the micrographs of the tested pins. The experimental results show that AE activity existed throughout the entire wear process, and it was the most prominent in the serious wear phase. The wear degree of the pin connections can be reflected qualitatively by the signal strength and the accumulative signal strength of the AE signals. In addition, two different wear forms can be distinguished by comparing the signal strength values of all specimens. Micrographs of all specimens confirm these results, and determine that the two wear forms include adhesive wear and abrasive wear. Furthermore, AE results demonstrated that adhesive wear is the main mode of wear for the low rotational speed pin connections, and the signal strength of the adhesive wear is around 190 times larger than that of abrasive wear. This feasibility study demonstrated that the developed acoustic emission technique can be utilized in the wear monitoring of pin connections in real time in a nondestructive way.
Methodology for Existing Railway Reconstruction with Constrained Optimization Based on Point Cloud Data
Authors: Li Fei , Ren Xiaochun , Luo Wenbing , Chen Xiuwan
Published: October 2018

The reconstruction of an existing railway is important for railway reformation or double-track design. Obtaining the curve parameters of the railway and the location of the main stake accurately and rapidly is the key issue for existing railway reconstruction. A new method based on point cloud data is proposed in this paper. The issue of reconstruction was transformed into an optimization problem by constructing the objective function and introducing the constraint. With consideration of the slope of the curves’ chord, the robust local weighted moving average method was used for de-noising. The time complexity was reduced greatly after separating the curve unit. The proposed method can obtain the coordinates of the main stake and the parameters of the railway by particle swarm optimization using a full direction search, combining the design requirements and geometric relations of the railway. Finally, some experiments on the design data and measured data were conducted to verify the validity of the proposed method. The results also show that the proposed method is very effective and useful for existing railway reconstruction.
A Novel Classification Optimization Approach Integrating Class Adaptive MRF and Fuzzy Local Information for High Spatial Resolution Multispectral Imagery
Authors: Zhou Yuejin , Zhang Hua , Xu Xiaoding , Li Mingpeng , Zheng Lihui , Zhu Yakun
Published: October 2018

This paper develops a novel classification optimization approach integrating class adaptive Markov Random Field (MRF) and fuzzy local information (CAMRF-FLI) for high spatial resolution multispectral imagery (HSRMI). Firstly, the raw classification results, including initial fuzzy memberships and class labels of every pixel, are achieved by a pixel-wise classification method for a given image. Secondly, the class adaptive MRF-based data energy function is developed to integrate class spatial dependency information. Thirdly, a novel spatial energy function integrating fuzzy local information is constructed. Finally, based on the total of data and spatial energies, the raw classification map is regularized by a global minimization of the energy function using its iterated conditional modes (ICM). The effectiveness of CAMRF-FLI is performed by two data sets. The results indicate it can refine the classification map in homogeneous areas, meanwhile, reduce most of the edge blurring artifact, and improve the classification accuracy compared with some conventional approaches.
Surface Crack Identification on a Cylinder Using the Signal Enhancement of the Scanning Laser Line Source Method
Authors: Liu Xuekun , Yang Shixi , Liu Yongqiang , Chi Yongwei , Gu Xiwen
Published: October 2018

Cylindrical structures play an important role in industrial fields. The surface crack is a typical defect in the cylindrical structures. Non-destructive surface crack detection of these structures is critical to the safe operation of the equipment. In this study, the signal enhancement of the scanning laser line source (SLLS) method is investigated by a numerical simulation method to identify the location and depth of the surface crack in the aluminum cylinder. A fully coupled explicit finite element model is established to study the signal enhancement of cylindrical surface waves on the aluminum cylinder. The simulation results indicate that the signal enhancement of the SLLS is more sensitive to the surface crack of a cylinder than that of the scanning laser detection (SLD) because of the wider span and higher peak. Due to the phase shift characteristics of surface waves on the cylinder, the maximum peak-to-peak amplitude of signal enhancement in the SLLS method (the SLLS peak) is affected by the detection position and diameter of the cylinder. Therefore, an optimization approach for detection position in SLLS is proposed for the location of surface crack on the cylinder. The locations of the surface crack on the solid cylinders with different diameters are investigated using simulated laser ultrasonic field data. Moreover, we find that the SLLS peak for signal enhancement can effectively respond to the crack depth within a limited scope which is dependent on the directivity pattern of the longitudinal waves.
GARLM: Greedy Autocorrelation Retrieval Levenberg–Marquardt Algorithm for Improving Sparse Phase Retrieval
Authors: Xiao Zhuolei , Zhang Yerong , Zhang Kaixuan , Zhao Dongxu , Gui Guan
Published: October 2018

The goal of phase retrieval is to recover an unknown signal from the random measurements consisting of the magnitude of its Fourier transform. Due to the loss of the phase information, phase retrieval is considered as an ill-posed problem. Conventional greedy algorithms, e.g., greedy spare phase retrieval (GESPAR), were developed to solve this problem by using prior knowledge of the unknown signal. However, due to the defect of the Gauss–Newton method in the local convergence problem, especially when the residual is large, it is very difficult to use this method in GESPAR to efficiently solve the non-convex optimization problem. In order to improve the performance of the greedy algorithm, we propose an improved phase retrieval algorithm, which is called the greedy autocorrelation retrieval Levenberg–Marquardt (GARLM) algorithm. Specifically, the proposed GARLM algorithm is a local search iterative algorithm to recover the sparse signal from its Fourier transform magnitude. The proposed algorithm is preferred to existing greedy methods of phase retrieval, since at each iteration the problem of minimizing the objective function over a given support is solved by using the improved Levenberg–Marquardt (ILM) method and matrix transform. A local search procedure such as the 2-opt method is then invoked to get the optimal estimation. Simulation results are given to show that the proposed algorithm performs better than the conventional GESPAR algorithm.
A Piezoelectric Actuator-Based Direct-Drive Valve for Fast Motion Control at High Operating Temperatures
Authors: Han Chulhee , Choi Seung-Bok , Han Young-Min
Published: October 2018

This paper experimentally investigates the control performances of a piezostack actuator direct-drive valve (PADDV) operating at high temperatures. In this study, the PADDV system is designed based on special specifications featuring a high operating temperature (150 °C) and wide control bandwidth (200 Hz). After manufacturing the PADDV with design limitations such as size and maximum input voltage to the piezostack actuator, the displacement of a spool located inside the valve system, which is directly related to the flow rate, is controlled at several different temperatures and motion frequencies. In order to undertake this, the PADDV system is installed inside a heat chamber equipped with air vessels and pneumatic–hydraulic cylinders. The piezoelectric actuator is partially insulated using an aerogel to prevent permanent damage due to high temperatures above 120 °C, which is higher than the Curie temperature. To control the valve system, a PID (proportional–integral–derivative) controller is realized in which control gains are properly tuned using fuzzy logic according to the change of temperature and frequency. It is shown from the experimental results that the proposed PADDV with thermal insulation can provide the target dynamic motion of 200 Hz at 150 °C by implementing the fuzzy-based PID controller.
Thermodynamic Analysis of Time Evolving Networks
Authors: Ye Cheng , Wilson Richard C. , Rossi Luca , Torsello Andrea , Hancock Edwin R.
Published: October 2018

The problem of how to represent networks, and from this representation, derive succinct characterizations of network structure and in particular how this structure evolves with time, is of central importance in complex network analysis. This paper tackles the problem by proposing a thermodynamic framework to represent the structure of time-varying complex networks. More importantly, such a framework provides a powerful tool for better understanding the network time evolution. Specifically, the method uses a recently-developed approximation of the network von Neumann entropy and interprets it as the thermodynamic entropy for networks. With an appropriately-defined internal energy in hand, the temperature between networks at consecutive time points can be readily derived, which is computed as the ratio of change of entropy and change in energy. It is critical to emphasize that one of the main advantages of the proposed method is that all these thermodynamic variables can be computed in terms of simple network statistics, such as network size and degree statistics. To demonstrate the usefulness of the thermodynamic framework, the paper uses real-world network data, which are extracted from time-evolving complex systems in the financial and biological domains. The experimental results successfully illustrate that critical events, including abrupt changes and distinct periods in the evolution of complex networks, can be effectively characterized.
The Study of Flipped-Classroom for Pre-Service Science Teachers
Authors: Jeong Jin Su , Cañada-Cañada Florentina , González-Gómez David
Published: October 2018

The relatively new methodology, flipped-classroom, is one of blended learning instruction methodologies in which the traditional-classroom is inverted. This methodology asserts that students can participate and engage more successfully in their class and can attain better learning when their classroom is flipped. This work presents a two-year study to measure the effects of the flipped-classroom model on the performance, perceptions, and emotions for teacher training students in science education. Particularly, this research was carried out during two courses, 2014/2015 and 2015/2016, in a general science subject. With a post-task questionnaire, we obtained the information to assess their performance, perceptions, and emotions, toward the class. The results confirmed that a statistically significant difference was found on all assessments with the flipped-classroom students, performing higher on average, showing favorable perceptions, and demonstrating positive emotions about the flipped-classroom model. Thus, the students were ready to take more courses pursuing a flipped-classroom model. The results achieved in this study show a promising inclination about the performance, perceptions, and emotions of students toward the flipped-classroom methodology, and will provide an entirely a new impetus for this relatively new instruction methodology.
Feedforward Control Based on Error and Disturbance Observation for the CCD and Fiber-Optic Gyroscope-Based Mobile Optoelectronic Tracking System
Authors: Luo Yong , Ren Wei , Huang Yongmei , He Qiunong , Wu Qiongyan , Zhou Xi , Mao Yao
Published: October 2018

In the mobile optoelectronic tracking system (MOTS) based on charge-coupled device (CCD) and fiber-optic gyroscope (FOG), the tracking performance (TP) and anti-disturbance ability (ADA) characterized by boresight error are of equal importance. Generally, the position tracking loop, limited by the image integration time of CCD, would be subject to a non-negligible delay and low-sampling rate, which could not minimize the boresight error. Although the FOG-based velocity loop could enhance the ADA of the system, it is still insufficient in the case of some uncertain disturbances. In this paper, a feedforward control method based on the results of error and disturbance observation was proposed. The error observer (EOB) based on the CCD data and model output essentially combined the low-frequency tracking feedforward and closed-loop disturbance observer (DOB), which could simultaneously enhance the low-frequency TP and ADA. In addition, in view of the poor low-frequency performance of the FOG due to drift and noise that may result in the inaccuracy of the observed low-frequency disturbance, the FOG-based DOB was used to improve the relatively high-frequency ADA. The proposed method could make EOB and DOB complementary and help to obtain a high-precision MOTS, for in practical engineering, we give more attention to the low-frequency TP and full-band ADA. Simulations and experiments demonstrated that the proposed method was valid and had a much better performance than the traditional velocity and position double-loop control (VPDC).
High Performance Graphene-Based Electrochemical Double Layer Capacitors Using 1-Butyl-1-methylpyrrolidinium tris (pentafluoroethyl) trifluorophosphate Ionic Liquid as an Electrolyte
Authors: Huffstutler Jacob D. , Wasala Milinda , Richie Julianna , Barron John , Winchester Andrew , Ghosh Sujoy , Yang Chao , Xu Weiyu , Song Li , Kar Swastik , Talapatra Saikat
Published: October 2018

There are several advantages to developing electrochemical double-layer capacitors (EDLC) or supercapacitors with high specific energy densities, for example, these can be used in applications related to quality power generation, voltage stabilization, and frequency regulation. In this regard, ionic liquids capable of providing a higher voltage window of operations compared to an aqueous and/or polymer electrolyte can significantly enhance the specific energy densities of EDLCs. Here we demonstrate that EDLCs fabricated using ionic liquid 1-butyl-1-methylpyrrolidinium tris (pentafluoroethyl) trifluorophosphate (BMP-FAP) as an electrolyte and few layer liquid-phase exfoliated graphene as electrodes show remarkable performance compared to EDLC devices fabricated with aqueous potassium hydroxide (6M) as well as widely used ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6). We found that graphene EDLC’s with BMP-FAP as an electrolyte possess a high specific energy density of ≈25 Wh/kg along with specific capacitance values as high as 200 F/g and having an operating voltage windows of >5 volts with a rapid charge transfer response. These findings strongly indicate the suitability of BMP-FAP as a good choice of electrolyte for high energy density EDLC devices.
Study on Low Temperature Oxidation Characteristics of Oil Shale Based on Temperature Programmed System
Authors: Du Wenzhou , Wang Yue , Liu Xuelin , Sun Lulu
Published: October 2018

Oil shale is a kind of high-combustion heat mineral, and its oxidation in mining and storage are worth studying. To investigate the low-temperature oxidation characteristics of oil shale, the temperature, CO, alkane and alkene gases were analyzed using a temperature-programmed device. The results showed that the temperature of oil shale underwent three oxidation stages, namely a slow low-temperature oxidation stage, a rapid temperature-increasing oxidation stage, and a steady temperature-increasing stage. The higher the air supply rate is, the higher the crossing point temperature is. Similar to coal, CO also underwent three stages, namely a slow low-temperature oxidation stage, a rapid oxidation stage, and a steady increase stage. However, unlike coal, alkane and alkene gases produced by oil shale underwent four stages. They all had a concentration reduction stage with the maximum drop of 24.20%. Statistical classification of inflection temperature of various gases as their concentrations change showed that the temperature of 140 °C is the key temperature for group reactions, and above the temperature of 140 °C, all alkane and alkene gases underwent the rapid concentration increase stage.
Effect of the Particle Size of Iron Ore on the Pyrolysis Kinetic Behaviour of Coal-Iron Ore Briquettes
Authors: Zheng Heng , Wang Wei , Xu Runsheng , Zan Rian , Schenk Johannes , Xue Zhengliang
Published: October 2018

High reactivity coke is beneficial for achieving low carbon emission blast furnace ironmaking. Therefore, the preparation of highly reactive ferro-coke has aroused widespread attention. However, the effects of the particle size of iron ore on the pyrolysis behaviour of a coal-iron ore briquette are still unclear. In this study, the effect of three particle sizes (0.50–1.00 mm, 0.25–0.50 mm and <0.74 mm) of iron ore on the thermal and kinetic behaviours of coal-iron ore briquettes were investigated by non-isothermal kinetic analysis. The results showed that the synergistic effect of iron ore and coal during coking mainly occurred during the later reaction stage (850–1100 °C) and smaller particle sizes of iron ore have a stronger synergistic effect. The addition of iron ore had little effect on T0 (the initial temperature) and Tp (the temperature at the maximum conversion rate) of briquette pyrolysis, however itgreatly affected the conversion rate and Tf (the final temperature) of the briquettes. T0 decreased with the decrease of iron ore particle sizes, while Tp and Tf showed opposite trends. After adding iron ore into the coal briquette, the reaction kinetics at all stages of the coal-iron ore briquettes changed. The weighted apparent activation energy of the caking coal (JM) briquette was 35.532 kJ/mol, which is lower than that of the coal-iron ore briquettes (38.703–55.627 kJ/mol). In addition, the weighted apparent activation energy gradually increased with decreasing iron ore particle sizes.
Analysis and Sizing of Power Distribution Architectures Applied to Fuel Cell Based Vehicles
Authors: Raga Carmen , Barrado Andres , Miniguano Henry , Lazaro Antonio , Quesada Isabel , Martin-Lozano Alberto
Published: October 2018

The fuel cell based vehicles powertrain is an extensive system that comprises a fuel cell (FC) as the primary energy source, a set of power converters both unidirectional and bidirectional and batteries or supercapacitors as secondary energy sources. Its design is a complex task that affects the mass, volume, cost, efficiency and fuel economy of the vehicle. This paper describes a graphic and straightforward sizing of the secondary energy sources needed to fulfil the vehicle load requirements, as well as the set of equations related to the mass, cost and volume of each one of the power distribution subsystems. Moreover, this paper analysis ten different power distribution architectures to conclude which is the most suitable secondary energy source, the minimum sizing, cost, volume and weight, depending on the amount of power delivered by the fuel cell. Also, a 1.6 kW fuel cell based architecture is implemented and testing. The experimental results confirm the proposed methodology.
Design and Analysis of Rotor Shapes for IPM Motors in EV Power Traction Platforms
Authors: Hwang Myeong-Hwan , Han Jong-Ho , Kim Dong-Hyun , Cha Hyun-Rok
Published: October 2018

The recent increase in the use of permanent magnet rotor motors underlines the importance of designing a rotor with an interior permanent magnet (IPM) structure, high power, and high efficiency. This study analyzed the rotor shapes of IPM motors for electric vehicles. Five types of motor rotors for automobiles were analyzed, including two hybrid vehicles. In order to minimize the number of variables in the analysis, the size of the motor stators was fixed and only the rotor shapes were modified to compare torque, torque ripple, efficiency and back-electromotive voltage. When the motor properties were compared as a function of rotor shape, the rotor shape with the smallest magnet volume exhibited excellent results for torque, efficiency and torque ripple.
Bond Graph Simulation of Error Propagation in Position Estimation of a Hydraulic Cylinder Using Low Cost Accelerometers
Authors: Algar Antonio , Codina Esteban , Freire Javier
Published: October 2018

The indirect calculation from acceleration of transversal displacement of the piston inside the body of a double effect linear hydraulic cylinder during its operating cycle is assessed. Currently an extensive effort exists in the improvement of the mechanical and electronic design of the highly sophisticated MEMS accelerometers. Nevertheless, the predictable presence of measurement errors in the current commercial accelerometers is the main origin of velocity and displacement measurement deviations during integration of the acceleration. A bond graph numerical simulation model of the electromechanical system has been developed in order to forecast the effect of several measurement errors in the use of low cost two axes accelerometers. The level of influence is assessed using quality indicators and visual signal evaluation, for both simulations and experimental results. The obtained displacements results are highly influenced by the diverse dynamic characteristics of each measuring axis. The small measuring errors of a simulated extremely high performance sensor generate only moderate effects in longitudinal displacement but deep deviations in the reconstruction of piston transversal movements. The bias error has been identified as the source of the higher deviations of displacement results; although, its consequences can be easily corrected.