bluuebunny/crossref_metadata_2025 huggingface dataset:
A cryptic cycle in haematopoietic niches promotes initiation of malaria transmission and evasion of chemotherapy
Authors: Lee Rebecca S. , Waters Andrew P. , Brewer James M.
Published: April 2018

Blood stage human malaria parasites may exploit erythropoietic tissue niches and colonise erythroid progenitors; however, the precise influence of the erythropoietic environment on fundamental parasite biology remains unknown. Here we use quantitative approaches to enumerate Plasmodium infected erythropoietic precursor cells using an in vivo rodent model of Plasmodium berghei. We show that parasitised early reticulocytes (ER) in the major sites of haematopoiesis establish a cryptic asexual cycle. Moreover, this cycle is characterised by early preferential commitment to gametocytogenesis, which occurs in sufficient numbers to generate almost all of the initial population of circulating, mature gametocytes. In addition, we show that P. berghei is less sensitive to artemisinin in splenic ER than in blood, which suggests that haematopoietic tissues may enable origins of recrudescent infection and emerging resistance to antimalarials. Continuous propagation in these sites may also provide a mechanism for continuous transmission and infection in malaria endemic regions.
Predictors of next-generation sequencing panel selection using a shared decision-making approach
Authors: Courtney Eliza , Li Shao-Tzu , Shaw Tarryn , Chen Yanni , Allen John Carson , Ngeow Joanne
Published: April 2018

The introduction of next-generation sequencing panels has transformed the approach for genetic testing in cancer patients, however, established guidelines for their use are lacking. A shared decision-making approach has been adopted by our service, where patients play an active role in panel selection and we sought to identify factors associated with panel selection and report testing outcomes. Demographic and clinical data were gathered for female breast and/or ovarian cancer patients aged 21 and over who underwent panel testing. Panel type was classified as ‘breast cancer panel’ (BCP) or ‘multi-cancer panel’ (MCP). Stepwise multiple logistic regression analysis was used to identify clinical factors most predictive of panel selection. Of the 265 included subjects, the vast majority selected a broader MCP (81.5%). Subjects who chose MCPs were significantly more likely to be ≥50 years of age (49 vs. 31%; p < 0.05), Chinese (76 vs. 47%; p < 0.001) and have a personal history of ovarian cancer (41 vs. 8%; p < 0.001) with the latter two identified as the best predictors of panel selection. Family history of cancer was not significantly associated with panel selection. There were no statistically significant differences in result outcomes between the two groups. In summary, our findings demonstrate that the majority of patients have a preference for interrogating a larger number of genes beyond those with established testing guidelines, despite the additional likelihood of uncertainty. Individual factors, including cancer history and ethnicity, are the best predictors of panel selection.
Time efficient whole-brain coverage with MR Fingerprinting using slice-interleaved echo-planar-imaging
Authors: Rieger Benedikt , Akçakaya Mehmet , Pariente José C. , Llufriu Sara , Martinez-Heras Eloy , Weingärtner Sebastian , Schad Lothar R.
Published: April 2018

Magnetic resonance fingerprinting (MRF) is a promising method for fast simultaneous quantification of multiple tissue parameters. The objective of this study is to improve the coverage of MRF based on echo-planar imaging (MRF-EPI) by using a slice-interleaved acquisition scheme. For this, the MRF-EPI is modified to acquire several slices in a randomized interleaved manner, increasing the effective repetition time of the spoiled gradient echo readout acquisition in each slice. Per-slice matching of the signal-trace to a precomputed dictionary allows the generation of T1 and T2* maps with integrated B1+ correction. Subsequent compensation for the coil sensitivity profile and normalization to the cerebrospinal fluid additionally allows for quantitative proton density (PD) mapping. Numerical simulations are performed to optimize the number of interleaved slices. Quantification accuracy is validated in phantom scans and feasibility is demonstrated in-vivo. Numerical simulations suggest the acquisition of four slices as a trade-off between quantification precision and scan-time. Phantom results indicate good agreement with reference measurements (Difference T1: −2.4 ± 1.1%, T2*: −0.5 ± 2.5%, PD: −0.5 ± 7.2%). In-vivo whole-brain coverage of T1, T2* and PD with 32 slices was acquired within 3:36 minutes, resulting in parameter maps of high visual quality and comparable performance with single-slice MRF-EPI at 4-fold scan-time reduction.
Multidrug-resistant Pseudomonas aeruginosa aggravates inflammatory responses in murine chronic colitis
Authors: von Klitzing Eliane , Ekmekciu Ira , Kühl Anja A. , Bereswill Stefan , Heimesaat Markus M.
Published: April 2018

The World Health Organization has rated multidrug-resistant (MDR) Gram-negative bacteria including Pseudomonas aeruginosa (Psae) as serious threat to human health. We here addressed whether chronic murine gut inflammation facilitates intestinal MDR Psae colonization and whether bacterial infection subsequently worsens colonic immunopathology. Converse to wildtype counterparts, Psae colonized the intestines of IL-10−/− mice with chronic colitis following peroral challenge, but did not lead to changes in intestinal microbiota composition. Psae infection accelerated both macroscopic (i.e. clinical) and microscopic disease (i.e. colonic epithelial apoptosis), that were accompanied by increased intestinal pro-inflammatory immune responses as indicated by elevated colonic numbers of innate and adaptive immune cell subsets and enhanced secretion of pro-inflammatory cytokines such as TNF and IFN-γ in mesenteric lymph nodes of Psae-infected as compared to unchallenged IL-10−/− mice. Remarkably, Psae-induced pro-inflammatory immune responses were not restricted to the gut, but could also be observed systemically as indicated by increased TNF and IFN-γ concentrations in sera upon Psae-infection. Furthermore, viable commensals originating from the intestinal microbiota translocated to extra-intestinal compartments such as liver, kidney and spleen of Psae-infected IL-10−/− mice with chronic colitis only. Hence, peroral MDR Psae-infection results in exacerbated colonic as well as systemic pro-inflammatory immune responses during chronic murine colitis.
Enhancement of UV Second-Harmonic Radiation at Nonlinear Interfaces with Discontinuous Second-order Susceptibilities
Authors: Zhao Xiaohui , Zheng Yuanlin , An Ning , Ren Huaijin , Deng Xuewei , Chen Xianfeng
Published: April 2018

We investigate the generation of ultraviolet (UV) second-harmonic radiation at the boundary of a UV transparent crystal, which is derived from the automatic partial phase matching of the incident wave and the total internal reflection. By adhering to another UV non-transparent crystal with a larger second-order nonlinear coefficient χ(2), a nonlinear interface with large disparity in χ(2) is formed and the enhancement of UV second-harmonic radiation is observed experimentally. The intensity of enhanced second harmonic wave generated at the nonlinear interface is up to 11.6 times that at the crystal boundary. As a tunable phase-matching method, it may suggest potential applications in the UV, and even vacuum-UV region.
Uses of selection strategies in both spectral and sample spaces for classifying hard and soft blueberry using near infrared data
Authors: Hu Menghan , Zhai Guangtao , Zhao Yu , Wang Zhaodi
Published: April 2018

In the current work, we attempt to leverage the fewer wavelengths and samples to develop a classification model for classifying hard and soft blueberries using near infrared (NIR) data. To do this, random frog selection and active learning approaches are used in the spectral space and the sample queue, respectively. To reduce the spectral number, a random frog spectral selection approach was applied to collect wavelengths informative with hardness. Prediction model based on 22 selected spectra gave slightly better results than that based on the full spectra. In terms of the selection operation in the sample space, the query by committee was validated to be suitable for blueberry hardness classification with the accuracy, precision and recall of 78%, 74% and 98% when taking only 25 sample queries. Its standard deviation curves of performance metrics are also located in regions of low values (around 0.05) and fluctuated steadily in shape, winning over those of the other 4 active learning strategies and random method. In summary, the respective uses of random frog and query by committee in the NIR spectral vector and the sample queue showed the considerable potential for establishing a simple but robust classifier for hard and soft blueberries with very low labeling cost.
Effects of litter feeders on the transfer of 137Cs to plants
Authors: Ishii Nobuyoshi , Murakami Masashi , Suzuki Takahiro , Tagami Keiko , Uchida Shigeo , Ohte Nobuhito
Published: April 2018

The effects of the Japanese horned beetle larvae on the transfer of 137Cs from a contaminated leaf litter to the leaf vegetable, komatsuna (Brassica rapa var. perviridis) was studied. Feces of the larvae which were fed 137Cs-contaminated leaf litter were added to a potting mix in which komatsuna plants were cultivated. The presence of feces increased the harvest yield of komatsuna, suggesting that feces provided nutrients for the plant growth. In addition, the amount of exchangeable 137Cs in leaf litter was experimentally confirmed to be enhanced by the presence of feces which were excreted by larvae feeding. However, there was no difference in the soil-to-plant transfer factor of 137Cs for the presence and absence of feces. Interactions between clay minerals and exchangeable 137Cs in the soil beneath the litter layer may diminish the root uptake of 137Cs. From these results, it was concluded that the effect of exchangeable 137Cs released from feces was limited for the transfer of 137Cs to plants if plant roots were not present in litter layers.
A novel competitive-displacement fluorescence assay for l-penicillamine based on the reaction between the target and N-acetyl-l-cysteine-capped CdTe quantum dots for copper ions
Authors: Huang Yunmei , Yang Jidong , Yuan Haiyan , Guo Yuan , Zeng Xiaoqing , Cheng Jiawei , Zhang Yuhui
Published: April 2018

CdTe quantum dots (CdTe QDs) were modified by N-acetyl-l-cysteine (NALC) as novel fluorescent probes and successfully utilized for the determination of l-penicillamine.
Floating catalyst CVD synthesis of single walled carbon nanotubes from ethylene for high performance transparent electrodes
Authors: Hussain Aqeel , Liao Yongping , Zhang Qiang , Ding Er-Xiong , Laiho Patrik , Ahmad Saeed , Wei Nan , Tian Ying , Jiang Hua , Kauppinen Esko I.
Published: April 2018

Manufacturing of high performance transparent conducting electrodes from very long and a high proportion of individual SWCNTs using the ethylene floating catalyst CVD process.
Aggregation-induced phosphorescence enhancement of Mn-doped ZnS quantum dots: the role of dot-to-dot distance
Authors: Zhang Jinyi , Tang Dandan , Yao Yadong , Hou Xiandeng , Wu Peng
Published: April 2018

The aggregation-induced phosphorescence enhancement (AIPE) of Mn-doped ZnS QDs is highly dependent on the dot-to-dot distance in the aggregates.
An experimental and computational study of CO2adsorption in the sodalite-type M-BTT (M = Cr, Mn, Fe, Cu) metal–organic frameworks featuring open metal sites
Authors: Asgari Mehrdad , Jawahery Sudi , Bloch Eric D. , Hudson Matthew R. , Flacau Roxana , Vlaisavljevich Bess , Long Jeffrey R. , Brown Craig M. , Queen Wendy L.
Published: April 2018

The work provides molecular level insight into the CO2adsorption properties of an isostructural series of MOFs, known as M-BTT.
Gold-catalyzed (4 + 2)-annulations between α-alkyl alkenylgold carbenes and benzisoxazoles with reactive alkyl groups
Authors: Mokar Bhanudas Dattatray , Jadhav Prakash D. , Pandit Y. B. , Liu Rai-Shung
Published: April 2018

This work reports new (4 + 2)-annulations of α-alkyl vinylgold carbenes with benzisoxazoles to afford 3,4-dihydroquinoline derivatives with high anti-stereoselectivity.
Anisotropic functionalization of upconversion nanoparticles
Authors: Ren Wei , Wen Shihui , Tawfik Sherif Abdulkader , Su Qian P. , Lin Gungun , Ju Lining A. , Ford Michael J. , Ghodke Harshad , van Oijen Antoine M. , Jin Dayong
Published: April 2018

Ligand competition directs heterogeneous bio-chemistry surface and self-assembly for upconversion nanoparticles.
Molecular mechanics of coiled coils loaded in the shear geometry
Authors: Goktas Melis , Luo Chuanfu , Sullan Ruby May A. , Bergues-Pupo Ana E. , Lipowsky Reinhard , Vila Verde Ana , Blank Kerstin G.
Published: April 2018

Shearing of short, dimeric coiled coils proceedsviathree competing timescale-dependent mechanisms: progressive helix uncoiling, uncoiling-assisted sliding and dissociation.
Solid state frustrated Lewis pair chemistry
Authors: Wang Long , Kehr Gerald , Daniliuc Constantin G. , Brinkkötter Melanie , Wiegand Thomas , Wübker Anna-Lena , Eckert Hellmut , Liu Lei , Brandenburg Jan Gerit , Grimme Stefan , Erker Gerhard
Published: April 2018

In solution the PCy3/B(C6F5)3 pair is rapidly deactivated by nucleophilic aromatic substitution. In the solid state (or in a fluorous liquid), however, it serves as an active frustrated Lewis pair to effectively split dihydrogen.
Anatomy of triply-periodic network assemblies: characterizing skeletal and inter-domain surface geometry of block copolymer gyroids
Authors: Prasad Ishan , Jinnai Hiroshi , Ho Rong-Ming , Thomas Edwin L. , Grason Gregory M.
Published: April 2018

Mesogeometric anatomy – 2D inter-material surfaces and 1D skeletons – extracted from triply-periodic, double-gyroid network assembled from triblock copolymers.
Capillary-driven binding of thin triangular prisms at fluid interfaces
Authors: Ferrar Joseph A. , Bedi Deshpreet Singh , Zhou Shangnan , Zhu Peijun , Mao Xiaoming , Solomon Michael J.
Published: April 2018

Thin, triangular prisms self-assemble into open networks via capillary interactions at flat air–water interfaces.
Apigenin inhibits C5a-induced proliferation of human nasopharyngeal carcinoma cells through down-regulation of C5aR
Authors: Zhang Yanshu , Cao Ying , Zhang Linlin , Feng Chunyan , Zhou Guangquan , Wen Guohua
Published: April 2018

Complement 5a (C5a) is able to induce the proliferation of human nasopharyngeal carcinoma (NPC) cells. Therefore, an effective method or drug that can specifically inhibit C5a-induced proliferation of human NPC cells needs to be developed. Reportedly, Apigenin has antiproliferative effects on a variety of cancer cells. However, the effect of Apigenin on NPC cell proliferation and its underlying mechanism are still unclear. Herein, the present study aimed to evaluate the effect of Apigenin on C5a-induced proliferation of human NPC cells and its possible mechanism through down-regulation of C5aR. We revealed that Apigenin in vitro could not only inhibit proliferation of NPC cells and but also reduce the expression of C5aR and P300/CBP-associated factor (PCAF) as well as the activation of signal transducer and activator of transcription 3 (STAT3) in NPC cells. Furthermore, Apigenin reduced the proliferation of human NPC cells triggered by C5a through negative regulation of C5aR/PCAF/STAT3 axis. These might provide a new insight into the function of Apigenin in cancer treatment, and also provide a potential strategy for treating human NPC through inhibition of C5aR expression on cancer cells.
Modified Welch Berlekamp Algorithm to Decode Reed Solomon Codes
Authors: Mahmudi Ali , Achmadi Sentot , Michael
Published: April 2018

In this paper, the Reed Solomon Code is decoded using the Welch-Berlekamp Algorithm. The RS Decoder is implemented using Hardware Description Language VHDL (VHSIC hardware Description Language) and simulated on Modelsim software. Some modifications have been carried out on the Welch Berlekamp algorithm in such a way that it is easier to implement. A pilot design double error correction RS(63, 59) decoder has been written in VHDL and simulated. The XILINX FPGA layout RS(63, 59) is then obtained.
Information System User Interface Design in Software Services Organization: A Small-Clan Case Study
Authors: Jitnupong Boonchoo , Jirachiefpattana Waraporn
Published: April 2018

A user interface (UI) is one of the most significant parts of an information system (IS). A user-friendly UI helps users to carry out their tasks with efficiency, effectiveness, and satisfaction. UI consists of five elements: metaphor, mental model, navigation, interaction, and appearance. Based on these, the designer must carefully select and design each element to be appropriate for the users. This research examines the influential process named user-centered design (UCD), a well-known process to raise product quality. Furthermore, the roles UI elements in IS development by observing it in a small family software services company in Thailand. The findings of this study show small family team is proper with UI design that concern in usability for user. Even though some UCD processes or UI elements are quite unclear, the clan culture helps team to design UI with flexibility, and unbiassed obtain comments from user.
Geometric Development of Point Absorber Wave Energy Conventer
Authors: Saptono Warpindyasmoro Heri , Gunadi Kartika
Published: April 2018

This paper describes how to design the shape of a floating object that will be used as a point absorber on wave energy converster. The buoyant shape to be analyzed is a tube has a flat top plane with varying bottom plane, i.e cylinder, hemisphare and cone. The analysis was conducted on the diameter of the object and the influence of the ocean wave period on the area where the apparatus was later applied in the southern coast of East Java. Using Moses's software, it is found that the diameter of the body is proportional to the period in which the maximum of Response Amplitude Operator floating object. The object with a flat bottom field (cylinder) produces the largest period, which is 10 s, followed by a curve shape of a hemisphere with a period of 9 s and last with a cone shape cone with a period of at least 8 s. This shows that the curvature of the bottom of the buoyancy can be adjusted according to the wave period to obtain maximum Response Amplitude Operator.
Turbine Design for Low Heat Organic Rankine Cycle Power Generation using Renewable Energy Sources
Authors: Susanto Herry , Abdullah Kamaruddin , Saepul Uyun Aep , Muhammad Nur Syukri , Meurah Indra Mahlia Teuku
Published: April 2018

In recent years, due to its feasibility and reliability, the organic rankine cycle has become a widespread concern and is the subject of research. In the organic rankine cycle system, the radial turbine component is a highly influential component of the high low performance resulting. This paper discusses the design of radial turbines for organic rankine cycle systems. The design stage consists of preliminary design and detail design with parametric methods on the working fluid R22 to determine the geometry and initial estimation of the performance of the radial turbine. After that, a numerical study of the fluid flow region in the radial turbine with R22 as the working fluid was performed. The analysis was performed using computational fluid dynamics of Autodesk Computational Fluid Dynamics Motion software on two models of real gas, k-epsilon and shear stress transport. From the results of this analysis, there is pressure, velocity and temperature distribution along the radial turbine blades and estimated performance under various operating conditions. Comparison between parametric and computational fluid dynamics analysis results show different performance. The difference is due to the computational fluid dynamics analysis already involving the real gas shear stress transport model.
Optimization Twist Angle of Darrius Wind Turbine with Computational Fluid Dynamics (CFD) Simulation for Highway Area Application
Authors: Ismail  , Augupta Pane Erlanda , Soleh
Published: April 2018

The research conducted to analyze and optimization of Darrius wind turbine based on air velocity and twist angle blade which can influence of turbine torque, turbine rotation speed and turbine power capacity. The method of research uses three steps that is the air velocity observation, wind turbine design, and simulation of wind turbine design. The twist angle as a variable parameter has degree angle of 0° and 30°. The result showed that the Darrius wind turbine with the twist angle of 30° which has chosen has the torque value is 0.285 N m that capable to increase the rotation speed is 6.42 rpm, and generate the turbine power capacity is 0.221 W. The research will be continuing to data validation with the result of pilot scale experiment.
Experimental Investigation of Air Conditioner using the Desiccant Cooling System in Equatorial Climates
Authors: Abdullah Kamaruddin , Saepul Uyun Aep , Muhammad Nur Syukri , Bamahry Alie , Imanda Rino , Meurah Indra Mahlia Teuku
Published: April 2018

Indonesia lies in the tropical climate which requires air conditioning to increase working productivity of the people. Up to now people are still using the compressive cooling system which uses Freon as the refrigerant, which have been known to have a negative environmental impact. Therefore, new cooling system which is environmentally friendly is now needed. Desiccant cooling system manipulates the humidity condition of outside air in such a way so that the final temperature should become at 25 °C and RH of 65 %. Since it does not require refrigerant, a desiccant cooling has the potential to be developed in a tropical country like Indonesia. In this study an experimental desiccant cooling system has been designed and constructed and tested under laboratory condition. Experimental results have shown that the resulting air temperature was 26.1 °C with RH of 55.6 %, and average cooling capacity was 0.425 kW. The COP was found to be 0.44.
Modified Floating Search Feature Selection Based on Genetic Algorithm
Authors: Homsapaya Kanyanut , Sornil Ohm
Published: April 2018

Classification performance is adversely impacted by noisy data .Selecting features relevant to the problem is thus a critical step in classification and difficult to achieve accurate solution, especially when applied to a large data set. In this article, we propose a novel filter-based floating search technique for feature selection to select an optimal set of features for classification purposes. A genetic algorithm is utilized to increase the quality of features selected at each iteration. A criterion function is applied to choose relevant and high-quality features which can improve classification accuracy. The method is evaluated using 20 standard machine learning datasets of various sizes and complexities. Experimental results with the datasets show that the proposed method is effective and performs well in comparison with previously reported techniques.
The Integration of Gasification Systems with Gas Engine by Developing Wet Tar Scrubbers and Gas Filter to Produce Electrical Energy from Biomass
Authors: Siregar Kiman , Alamsyah Rizal , Ichwana  , Sholihati  , Tou Saminuddin , Cristian Siregar Nobel
Published: April 2018

The need for energy especially biomass-based renewable energy continues to increase in Indonesia. The objective of this research was to design downdraft gasifier machine with high content of combustible gas on gas engine. Downdraft gasifier machine was adjusted with the synthetic gas produced from biomass. Besides that, the net energy ratio, net energy balance, renewable index, economic analysis and impact assessment also been conducted. Gas engine that was designed in this research had been installed with capacity of 25 kW with diameter and height of reactorwere 900 mm and 1 000 mm respectively. The method used here werethe design the Detailed Engineering Design, assembly, and performance test of gas engine. The result showed that gas engine for biomass can be operated for 8 h with performance engine of 84 % and capacity of 25 kW. Net energy balance, net energy ratio, and renewable index was 30 MJ/kW h electric; 0.89; 0.76 respectively. The value of GHG emission of Biomass Power Generation is 0.03 kg-CO2 eq per MJ. Electrical production cost for Biomass Power Generation is about IDR 1 500 per kW h which is cheaper than solar power generation which is about of IDR 3 300 per kW h.
The Encyclopedia of Virtual Art Carving Toraja - Indonesia
Authors: Sudianto Lande , Simon Petrus
Published: April 2018

The unity of local culture in Indonesia is the national culture which represented the identity of Indonesia. There are many cultural resources of our nation which needs to preserved and improved to maintain the national identity of Indonesia. The art of crafting from Toraja contains value and philosophy which based on the values of local wisdom as the part of Toraja and national culture. The application of Virtual Encyclopedia of Toraja Crafting Art which based on information and communication technology (ICT) is developed in order to integrate the culture in education for preservation, improvement, and education of cultural noble values for Indonesia especially the culture of crafting art in Toraja. There are 128 kinds of Toraja crafting which are divided into four groups: i) Garontok Passuraq; ii) Passuraq iii) Todolo; iv) Passuraq Malollek; v) Passuraq Pakbarean. Toraja crafting has denotative and connotative meaning. The explicit and implicit meanings in Toraja cultural make the Toraja culture become very interesting and challenging. The explicit meaning of Toraja crafting is called denotative meaning which is objective. Meanwhile, the implicit meaning of Toraja crafting is called connotative meaning which is subjective.
Production Capacity of Several Hybrid Genotypes of Jatropha curcas Linn. for Five Years in Pasuruan, East Java – Indonesia.
Authors: Maftuchah  , Zainudin Agus , Ikhwan Ali , Purnama Adi , Kok Kuan Lim
Published: April 2018

Jatropha curcas Linn. is one of shrubs mainly exist in tropical area. The research team has succeeded to produce several excellent hybrid genotypes which then were planted to be tested its production capacity for 5 yr. Those genotyes were: genoptype 5 (HS49 × SP34), genotype 6 (HS49 × SM35), genotype 7 (HS49 × IP1A), and genotype 18 (SP16 × SM35). This research aims at finding out the production capacity of several hybrid genotypes of J. curcas Linn. which was conducted for 5 yr in Kedung Pengaron, Pasuruan. The research was arranged in Randomized Complete Block Design with four repetitions. Each block contained 20 plants, with plant treatment of hybrid result of genotype 5 (JC5), 6 (JC6), 7 (JC7), 18 (JC18) and two comparators of IP3A and IP3P. Observation was conducted on the number of fruit bunches and fruit on each plant, the number of fruit per plant, seed dry weight per plant. The study showed that J.curcas hybrids of genotypes JC5, JC7 and JC18 had higher production capacity (in term of number of fruit per plant, seed dry weight per plant and dry weight of 100 seeds) than other genotypes (JC6, IP3A, IP3P) in environment with drought stress.
Indonesian Stock Prediction using Support Vector Machine (SVM)
Authors: Santoso Murtiyanto , Sutjiadi Raymond , Lim Resmana
Published: April 2018

This project is part of developing software to provide predictive information technology-based services artificial intelligence (Machine Intelligence) or Machine Learning that will be utilized in the money market community. The prediction method used in this early stages uses the combination of Gaussian Mixture Model and Support Vector Machine with Python programming. The system predicts the price of Astra International (stock code: ASII.JK) stock data. The data used was taken during 17 yr period of January 2000 until September 2017. Some data was used for training/modeling (80 % of data) and the remainder (20 %) was used for testing. An integrated model comprising Gaussian Mixture Model and Support Vector Machine system has been tested to predict stock market of ASII.JK for l d in advance. This model has been compared with the Market Cummulative Return. From the results, it is depicts that the Gaussian Mixture Model-Support Vector Machine based stock predicted model, offers significant improvement over the compared models resulting sharpe ratio of 3.22.
Web-Based Robotics Laboratory
Authors: Santoso Petrus , Khoswanto Handry , Njoto Sandjaja Iwan
Published: April 2018

In the education world, the number of web-based system is growing substantially in the past few years. Many web-based teaching tools has been developed to help students expand his knowledge. This paper presents a web-based laboratory to augment learning experiences in the field of robotics. The designed laboratory consists of a robotic arm with laser pointer, projection platform and web-based interface. The laboratory is used to learn about inverse kinematics and forward kinematics problems. Students enter the input parameters through web interface, server calculate output parameters and sent it to the robot. The web interface displays the movement result and turn on the laser pointer to the projection field. Preliminary testing concerning interface usability, access control mechanism and command queueing shows that the system working as expected.
Design and Bandwidth Optimization on Triangle Patch Microstrip Antenna for WLAN 2.4 GHz
Authors: Sotyohadi  , Afandi Riken , Rachmad Hadi Dony
Published: April 2018

In this paper, single and dual element triangle patch microstrip antenna for WLAN 2.4 GHz is designed, analyzed and fabricated. Both proposed design utilized proximity feeding techniques. Afterwards the design is simulated on HFFS and optimized, which finally the dimension of both design for frequency 2.4 GHz is obtained. The best simulation result for both single and dual element triangle patch microstrip antenna is used as reference for fabrication on FR4 substrate with dielectric constant (□r) = 4.4 and thickness (h) 1.6 mm. The measurement result showed that the single element can achieve return loss (S11) -51.913 dB and VSWR 1.005 9 at 2.417 GHz, and then for dual element the result for return loss (S1) is -48.213 8 for VSWR 1.007 8 at 2.463 GHz. Compared to coaxial feeding technique, the proximity feeding has better parameter performance.
Spelling Correction for Text Documents in Bahasa Indonesia Using Finite State Automata and Levinshtein Distance Method
Authors: Christanti Mawardi Viny , Susanto Niko , Santun Naga Dali
Published: April 2018

Any mistake in writing of a document will cause the information to be told falsely. These days, most of the document is written with a computer. For that reason, spelling correction is needed to solve any writing mistakes. This design process discuss about the making of spelling correction for document text in Indonesian language with document's text as its input and a .txt file as its output. For the realization, 5 000 news articles have been used as training data. Methods used includes Finite State Automata (FSA), Levenshtein distance, and N-gram. The results of this designing process are shown by perplexity evaluation, correction hit rate and false positive rate. Perplexity with the smallest value is a unigram with value 1.14. On the other hand, the highest percentage of correction hit rate is bigram and trigram with value 71.20 %, but bigram is superior in processing time average which is 01:21.23 min. The false positive rate of unigram, bigram, and trigram has the same percentage which is 4.15 %. Due to the disadvantages at using FSA method, modification is done and produce bigram's correction hit rate as high as 85.44 %.
Improved Fractographic Strength Estimates Based on Surface Profilometry
Authors: Ma Lingyue , Dugnani Roberto
Published: April 2018

Fractography is a valuable method that uses post-mortem topographical information to estimate the stress field near the fracture origin and help establish the root cause of failures. Typically, in glass and ceramics the mirror radius is one of the features sought for by fractographers since its length could be empirically related to the sample’s strength. The mirror radius is usually subjectively estimated by fractographers though microscopy measurements. Nonetheless, variations in the estimates introduced by inconsistent viewing modes and the subjectivity of observers could lead to substantial errors even when standard protocols such as ASTM C1678 were followed. In this manuscript, a novel method combining a fracture mechanics model describing the mist formation in silicate glasses with profilometry data carried out by confocal laser scanning microscope is introduced. The new method was shown to be able to objectively establish the mirror-mist boundary. Furthermore, it was found that the proposed technique was repeatable within 2% regardless of the magnification or imaging mode used. Whereas the average strength estimated per ASTM C1678 by eight individual observers was influenced by both the magnification and the imaging mode used and displayed standard deviation of over 3%.
Flexible Hinge Parameter Design and Performance Simulation of Vibration Assisted Machining Platform
Authors: Yan Yixiong
Published: April 2018

Vibration assist machining is a modern mechanical manufacturing technology which is aimed at achieving an efficient high-quality machining. This article focuses on a new-type vibration assisted machining platform which based on the stiffness and frequency requirement to obtain the key structural parameter and nature frequency of the platform by using the finite element method. Subsequently, static strength of the platform has been analyzed. Moreover, different excitation frequencies of the piezoelectric ceramics have been loaded at two vertical directions. The trajectory stability and characteristics of the platform under different actuating frequency have been figured out by using the finite element multi-body contact transient response analysis method. The results show that the nature frequency excitation results in large and destructive displacement. The steady-state response trajectory of the platform is elliptical under different excitation frequencies while under high excitation frequency it would become an elliptical moving. Once the unstable vibration time of platform increase, the unstable vibration amplitude would increase. The research results can provide a basis for the development of a new-type vibration assisted machining platform and the processing technology.
A Comparison of Effective Tension Calculation for Design Belt Conveyor between CEMA and DIN Standard
Authors: Satria Iman , Rusli Meifal
Published: April 2018

In the present era, many industries are demanding material transfer equipment that works maximally and cheaply. Belt Conveyor is one of the most efficient material transfer equipment compared to heavy equipment or other transportation equipment, because it can transport the material in large capacity. When designing conveyor belts, many industries want large transport capacity at low cost. One of the cost savings can be done with low motor power consumption. Many standards describe the effective tension calculation on the conveyor belt in detail with the parameters, since the effective tension calculation results are essential for determining motor power. This paper aims to analyze the effective tension on conveyor belts using CEMA 5th, CEMA 6th and DIN 22101 standards with case studies of 1000 TPH carrying capacity and 3 m/s conveyor speed. The difference between CEMA and DIN when determining the effective tension is on the use of coefficient of friction, because DIN uses a global coefficient of friction while CEMA uses different friction coefficients on idler, belt and material. This difference in coefficient of friction results in different ways of calculating the resistance being the accumulation of the effective tension. The result is an effective tension value using DIN 22101 standard of 22,148.16 N with motor power consumption of 66.5 kW, while effective tension value using CEMA 5th standard is 32.201.66 N with motor power consumption 96.47 kW, and effective tension value using CEMA 6th standard is 29,686.48 N with 89.06 kW motor power consumption.
A Braked Tail Cover Separation Concept and Simulation of Separation Process
Authors: Huang Mei , Jiang Yi , Wang Boman
Published: April 2018

Large-scale missiles are generally catapulted by the ejector. And a tail cover is used to protect the first stage rocket engine. When the missile reaches the predetermined height, the tail cover should be separated timely so that the engine can work properly. In this paper, a braked tail cover separation concept is proposed. And a new type of tail cover separation device is designed according to the concept. Firstly, the forces analysis and the internal ballistic simulation of ejection are conducted before setting working conditions. And then, the finite element software Abaqus is adopted to achieve the simulation of tail cover separation process. Through analyzing the obtained results, it’s concluded that the braked tail cover separation concept is feasible. Moreover, the influence of material changes on the braking effects is also studied.
A Novel Method on Min–Max Limit Protection for Aircraft Engine Control
Authors: Shu Wenjun , Yu Bing , Ke Hongwei
Published: April 2018

Min–Max selector structure is widely employed in current aircraft engine control logic. And the structure must provide desired thrust and prevent the engine from exceeding any safety or operational limits. In this paper, a new control scheme, that is Min–Max selector structure composed of Sliding Mode (SM) regulator and linear regulator, is presented. The main regulator is a linear regulator and all limit regulators are SM regulators. It could overcome the possibility of limit violation for the traditional Min-Max, and don’ t need the augmented state references that is one drawback of SMC Min-Max(all regulators are SM regulator). The simulation results show that the proposed approach could effectively prevent limit violation and can improve Min–Max limit protection for aircraft engine control.
Distributed Cooperative Control for Stepper Motor Synchronization
Authors: Yague Sauro J , Carmenaty Guillermo Reyes , Blanco Alejandro Rolán , Cerrada Aurelio García
Published: April 2018

This paper describes the design and simulation of a distributed cooperative control algorithm based on multi-agents to synchronize a group of stepper motors. Modeling of the two-phase hybrid stepper motor in closed loop is derived in {d - q} rotary reference frame, based on field-oriented control techniques to provide torque control. The simulation obtained by MATLAB-Simulink shows that the distributed cooperative control effectiveness depends on the network topology defined by the graph.
Measurement of residual stresses and toughness in Ti-6Al-4V material produced by laser beam manufacturing
Authors: Quénard Olivier , Dorival Olivier , Guy Philippe , Brethome Kevin
Published: April 2018

This study deals with the measurement of residual stress by the hole drilling method in Ti-6Al-4V samples obtained by Laser Beam Manufacturing after stress relieving. Indeed, it was of high interest to check the efficiency of such a thermal post-treatment. The influence of the orientation of both the sample and the notch is evaluated from a toughness point of view, and the obtained values are compared to that of similar parts submitted to Hot Isostatic Pressing after stress relief treatment. A more isotropic behaviour were detected on the HIPed samples (with respect to that of the stress relieved ones) with a higher average value. This development is discussed from both residual stress and microstructural points of view.
Glass Gob Modeling and Experimental Validation Using a Drop Test
Authors: Biosca Adrià , Borrós Salvador , Clemente Vicenç Pedret , Granada Andrés-Amador García
Published: April 2018

Glass blowing to create bottles with specific thickness distribution profiles requires several experimental iterations. Such iterations are expensive and increase the time to market. The use of simulation pretends to decrease the amount of prototypes by doing virtual validation of glass blowing molds. To feed simulations with realistic physical values, a gob drop test has been designed. This test provides valuable experience on the use of the software and validates heat transfer, viscosity and other physical parameters. Gob drop test was chosen for the possibility to record the test with infrared thermal cameras. Gob obtained similar shapes when dropped on a cast iron plate for both central and side sections with longer cooling of about 25°C. Such technique allowed the user to gain experience on the use of software and obtain valuable physical parameters for future glass blowing optimization.
Effect of Gr Contents on Wear Properties of Al2024/MgO/Al2O3/Gr Hybrid Composites
Authors: Ovalı İsmail , Esen Cemal , Albayrak Sevda , Karakoç Halil
Published: April 2018

In the present study, hybrid metal matrix composites, Al2024/10Al2O3, Al2024/10Al2O3/3MgO, Al2024/10Al2O3/6MgO, Al2024/10Al2O3/3MgO/1.5 Gr, Al2024/10Al2O3/3MgO/3Gr, and reinforcement samples (AA 2024) produced with powder metallurgy process. AA 2024 and reinforcement powders were determined mixture rations and separately mixed during 30 minutes in a three-dimensional Turbula mixer. The mixed compositions were pressed at 300 MPa and sintered at 550°C during 1 h. After that, three materials were extruded at the same temperature. Experimental results show that hybrid metal matrix composites (HMMCs) a better wear resistance than the reinforcement samples because of higher hardness. Gr behave as a lubricant during wear process. The wear resistance of HMMCs can be optimized with controlling of the reinforcement content and type.
Development of High Precision Vehicle Dynamic Model with an Intelligent Torque Transfer System (All-Wheel Drive System)
Authors: Pyun Beom-Joon , Moon Chul-Woo , Jeong Chang-Hyun , Jung Do-Hyun
Published: April 2018

High precision vehicle simulation environment is required for development of control system of any newly suggested intelligent system. Hence, a high precision full-vehicle simulation environment integrated with an intelligent torque transfer system should be developed for an advanced control logic for enhancement of vehicle stability. In the perspective of making enhanced AWD system, there are many kinds of methods to make the system. And a controller part of the AWD module is regarded as a major part of the system development in consideration of enhancement of the vehicle stability with the suggested AWD system. Therefore, in this study, high precision full-vehicle simulation environment is developed for the development of an intelligent control system of the AWD module. In order to make models for the simulation, vehicle test is performed with a commercial vehicle, and the several performance tests of the developed AWD system are also conducted in a laboratory. Then, the simulation environment comprised of several models of important sub-systems is developed based on the previously conducted test results, and the developed simulation environment is verified by comparing the simulation results to the test results.
Design of Hydraulic Bushing and Vehicle Testing for Reducing the Judder Vibration
Authors: Kim Youngman , Jeong Sangjin , Nguyen Van-Quyet , Boo Kwangsuck , Kim Heungseob
Published: April 2018

Generally, judder vibration is a low-frequency vibration phenomenon caused by a braking force imbalance that occurs when a vehicle is lightly decelerated within a range of 0.1 to 0.2g at a speed of 120 to 60 km/h. This comes from the change in the brake disk thickness (DTV), which is mainly caused by the side run-out (SRO) and thermal deformation. The adoption of hydro-bushing in the low arm G bushings of the vehicle front suspension has been done in order to provide great damping in a particular frequency range (<20Hz) in order to prevent this judder vibration from being transmitted to the body. The hydro bushing was formulated using a lumped parameter model. The fluid passage between the two chambers was modelled as a nonlinear element such as an orifice, and its important parameters (resistance, compliance) were measured using a simplified experimental setup. The main design parameters are the ratio of the cross-sectional area of the chamber to the fluid passage, the length of the fluid passage, etc., and their optimal design is such that the loss angle is greater than 45 ° in the target frequency range of 10 to 20 Hz. The hydro bushing designed for reducing the judder vibration was prepared for the actual vehicle application test and applied to the actual vehicle test. In this study, the proposed hydro bushing was applied to the G bushing of the low arm of the front suspension system of the vehicle. The loss angle of the manufactured hydro bushing was measured using acceleration signals before and after passing through the bushing. The actual vehicle test was performed on the noise dynamometer for the performance analysis of the judder vibration reduction.
Effects of Injection Molding Process Conditions on Physical Properties of EPDM Using Design of Experiment Method
Authors: Kim Young Shin , Jeon Euy Sik , Hwang Eui Seob
Published: April 2018

The process variables such as time and temperature during the EPDM-injection molding not only change the physical properties of the raw material but also affect the insertion and separations forces when a grommet product is molded and mounted on a car body. Using the design of experiments method, the major factors in the injection molding process were considered to analyze their effects on the physical properties of the obtained EPDM materials. Test pieces were prepared under different process conditions, tensile strength and elongation were measured, and their correlation was analyzed.
A Study on Multi-body Dynamic Modelling and Optimization for Mechanical Quick Closing Valve
Authors: Bo Wang , Junyan Li , Lifang Wu , Xuekai Chen
Published: April 2018

The multi-body dynamic modelling and optimization methods of mechanical quick closing valve are studied in this paper. The Lagrange equation is specified characterizing the closing process. Normal contact force and tangent friction force between the components are obtained by using equivalent spring-damper model and no-linear coulomb friction model. The theoretical result of the valve’s kinematic response is verified by the experiment. In order to analyse the relationship between structural parameters and the closing behaviour intuitively, a single degree of freedom model is provided. It is shown that the mass of the control rod is the key parameter exerting important influence on the cut-off time of the valve. The cut-off time will be shortened by about 1.2ms while the mass of control rod reduces 0.01kg.
Design and Performance Analysis of Contra-rotating Pumpjet Propulsor under Condition of Torque Unbalance
Authors: Wang Xiao-er , Zhang Zhen-shan , Zhang Meng
Published: April 2018

In order to balance the torque of front rotor and rear rotor of underwater vehicle, the analysis of the speed triangles at the inlet and outlet of the front and rear rotor has been done. Then, the thought of using contra-rotating pumpjet to achieve the objective was raised. The stator is installed behind the rear rotor so as to ensure the overall torque of the propulsor balance, at the same time, the stator can also support the shroud of the propulsor. the parameter design of the rotor and the stator has been carried out by using the three dimensional inverse design method. At last, the performance of the designed pumpjet propulsor is obtained when it is installed on the underwater vehicle By using computational fluid dynamics. The results show that the total torque of the propulsor is reduced to 1.8 N * m on the design point although the power difference ratio of the front rotor and the rear rotor is 20%. The torque ratio is also reduced from 4.6% to 0.4%, which is good to meet the propulsor balance requirement and verifies the 3-D design method of pumpjet is effective.