bluuebunny/crossref_metadata_2025 huggingface dataset:
Riset Antena – State of the Art
Authors: Alaydrus Mudrik
Published: March 2017

Riset antenna telah mengalami perjalanan panjang, seiring dengan perkembangan teknologi wireless dan aplikasi sensor serta radar. Secara garis besar, jenis antenna bisa dikategorikan menjadi antenna kawat (dipole, yagi), antenna waveguide (aperture, horn, slot), antenna reflector dan antenna mikrostrip. Dalam perancangan antenna para insiyur selalu merujuk pada katalog antenna yang telah ada dan melakukan modifikasi (menambahkan atau mengurangi sesuatu, atau memvariasikan parameter) untuk memenuhi spesifikasi yang diminta. Tulisan ini memberikan ulasan riset terkini antenna, dengan lebih menekankan pada lima bidang: metoda komputasi elektromagnetika, modifikasi antenna, material penyusun, aplikasi yang baru dan pengukuran antenna. Sampai dengan awal 2015 ditemukan sangat banyak riset tentang antenna di pelbagai publikasi yang ada.
Analisa Interferensi Wireless Traffic Light Terhadap Remote Kunci Mobil
Authors: Fikiansyah Felki
Published: March 2017

Lampu lalu lintas atau traffic light di gunakan untuk mengatur kelancaran di setiap persimpangan dengan cara memberikan kesempatan jalan setiap arah dengan cara bergantian .Karena fungsinya begitu penting maka lampu lalu lintas tersebut harus di kendalikan semudah mungkin . Sejalan dengan berkembangnya teknologi wireless sehingga pada saat ini untuk mengontrol setiap lampu sudah menggunakan wireless yang sebelumnya masih menggunakan jaringan kabel bawah tanah. Hal ini sangat memudahkan pemasangan Wireless traffic light tersebut sehingga para kontraktor untuk instalasi di lapangan tanpa harus melakukan penggalian kabel jaringan bawah tanah. Dalam tesis ini melakukan penelitian analisa pengaruh wireless traffic light terhadap remote kunci mobil . Kedua system tersebut mempunyai frekwensi carier yang berdekatan yaitu 433 – 434 MHz. Untuk menganalisa interferensi tersebut di gunakan metode settingan variasi time delay dalam pancaran module wireless traffic light controller terhadap remote kunci mobil, hal ini untuk mencari settigan variasi time delay dapat meminilasir pengaruh wireless traffic light controller terhadap remote kunci mobil. Identifikasi frekwensi carier dari simulasi di lapangan terbuka wireless traffic light controller dan remote kunci mobil pada frekwensi 433 MHz dan 433 MHz. Dengan settingan variasi time delay 0s , 0,2s dan 0,5s selama experiment di lapangan terbuka . Hasil penelitian menunjukan pada time delay 0s dan 0,2s menunjukan probabillitas interferensi yang paling tinggi di atas 99 % terhadap remote kunci mobil. Untuk settingan time delay 0,5s pada wireless traffic light controller probabilitas interferensi 2% pada jarak 5 M terhadap remote kunci mobil.
Designing of Hairpin-Line Band Pass filters for DCS, UMTS and LTE-Systems
Authors: Sayidi Muhammad , Alaydrus Mudrik
Published: March 2017

Bandpass filters are essential components in any wireless systems. They are designed for selecting desired signal from other signals. Especially in crowded frequency spectrums, accurate filter characteristics are required to guarantee the performance of the overall systems. DCS, UMTS and LTE systems are the actual communication systems used by hundred million users. Bandpass filters designed here is based on hairpin line structures and implemented in microstrip technology. The filters are five order Chebychev’s bandpass filters. The center frequency of each system determines the total length of the U-form hairpin structure. The design starts with exploiting the coupling between the resonators. The coupling between two adjacent resonators is determined by the fractional bandwidth of the system and the element value derived from the Chebychev’s approximation. The value of the coupling factor leads to the distance between two adjacent resonators. The simulation results conform to the specifications given in the standards. In general, the measurements verify the simulation. We see worse reflection factors and more insertion loss eventually due to bad soldering of the connectors to the filters. The shifting and width of the pass regions are also observed, which are probably due to the finite accuracy in prototyping the filters.
Analisis Strategi Badan Regulasi di Era Konvergensi
Authors: Siswanto Siswanto
Published: March 2017

Industri telekomunikasi mengalami peningkatan demand data yang sangat signifikan yakni hingga akhir 2011 akan ada 6,07 miliar koneksi melalui seluler di seluruh dunia atau setara dengan 84% penduduk dunia. Pada Juli 2010, jumlah mobile internet sudah mencapai 5 miliar pengguna atau setara dengan 74% populasi, bertumbuh signifikan jika dibandingkan estimasi 2008 yang tercatat 4 miliar atau 64% dari total polulasi. Artinya, kini satu dari tiga penduduk dunia telah online. Konverensi adalah Kemampuan jaringan yang berbeda dalam membawa layanan yang serupa (misal suara melalui IP (VoIP) atau Switched Network, video melalui TV kabel atau ADSL, atau kemungkinan lain, kemampuan untuk memberikan macam layanan dalam satu jaringan tunggal yang disebut “triple play” Selama dua dekade terakhir, sebagian besar pasar telekomunikasi mencapai , banyak dengan titik puncak regulasi meliputi regulator terpisah, kompetitif dan privatisasi pada penelitian ini mengunakan metode benchmark untuk membandingkan badan regulasi dengan negara sampel India, Indonesia, Malaysia, dan Singapura meliputi sisi keefektifan regulator, statistik pertumbuhan ICT. Tujuan yang hendak dicapai dalam penelitian ini adalah :mencari penyebab ketertinggalan pertumbuhan ICT di Indonesia, mengetahui seberapa efektif regulator di Indonesia dibandingkan dengan negara – negara di kawasan ASEAN.
Strategi LPS-RTV Dalam Era Siaran Digital Yang Menjadi Salah Satu Penyelenggara Multipleksing Di Wilayah Jabodetabek
Authors: Muslim Muslim , Krisnadi Iwan
Published: March 2017

Dengan perkembangan Teknologi konvergensi, serta mengacu padaperaturan Menteri Komunikasi dan Informatika Indonesia Nomor36/PER/M. KOMINFO/11/2012. tentang Persyaratan Teknis Alat danPerangkat Pemancar Televisi Siaran Digital Berbasis Standar DigitalVideo Broadcasting Terrestrial – Second Generation DVB-T2. Yangmana standar generasi kedua ini memiliki keunggulan dari generasisebelumnya diantaranya ada penghematan 50% daya dan tambahankapasitas data ratenya mencapai 40 Mbit/s. Dengan menggunakanCOFDM – Modulasi 64QAM untuk penerimaan tidak bergerak dan256QAM untuk HDTV. Digital Video Broadcasting generasi kedua(DVB-T2) ini sebagai standar yang resmi digunakan di Indonesia.Dengan menggunakan Analisa SWOT kinerja di suatu instansi dapat dilihat apakah Strategi perusahaan tersebut masih sesuai untuk dijalankanoleh manajemen perusahaan itu untuk mencapai tujuan yang diharapkankedepannya.
Feasibility Analysis of Implementation 3G Macro Additional Sector JABO Area using Techno-Economic Approach
Authors: Krisnadi Iwan , Tanjung Intan Kumalasari
Published: March 2017

The increasing number of operators, making competition in the telecommunications industry are becoming increasingly stringent. These circumstances spurred operators to compete in achieving the best quality of services. Macro Additional 3G Sector (LTC) Project is one effort of the operator in maintaining the quality of data services. The general philosophy of the design of telecommunications networks are getting the best performance with minimal implementation costs. In this work will be analyzed with the techno-economic approach for the feasibility of the implementation of 3G Macro Additional Sector Project by operator telecommunication in Jakarta. Analysis model used is based on the principle of techno-economic by throughput and number of user approach with bottom-up models, to determine the design of 3G Macro Additional Sector Project, and then measure the feasibility of the costs incurred for the implementation of 3G Macro Additional the Sector Project.
Análisis de la percepción que tiene el estudiantado de sexto y sétimo grados sobre su ingreso a la educación secundaria
Authors: Sanabria Hernández Marcela , Marín Gálvez Georgina , Espinoza Ruiz Arlene
Published: March 2017

El presente artículo responde a una investigación donde se analiza la percepción que tiene el studiantado de sexto y sétimo grados, sobre su ingreso a la educación secundaria. Se busca ubicar a la institución educativa como un ente protector siempre y cuando plantee las estrategias que favorezcan la permanencia del alumnado en ella, superando las dificultades que pueden generarse al pasar de un nivel a otro. Además el artículo ofrece una serie de conclusiones donde se rescata la opinión del estudiantado y los aspectos más relevantes para favorecer un adecuado proceso de transición. Este artículo presenta información de interés para profesionales interesados en materia de niñez, adolescencia y educación.
La educación religiosa en Costa Rica. Aproximaciones teóricas del campo religioso posteriores al voto de la Sala Constitucional
Authors: Cortés Campos Alexander
Published: March 2017

Este ensayo busca realizar un debate crítico en torno a la enseñanza de la Educación Religiosa en Costa Rica, teniendo como referente la sentencia de la Sala Constitucional que anuló la Missio Canónica. A partir de este escenario se exploran los antecedentes y las reacciones al voto de la Sala IV. También se analizan algunas aproximaciones teóricas del campo religioso para determinar la situación de la Educación Religiosa posterior al fallo constitucional.
The influence of royal board of directors and other board characteristics on corporate risk disclosure practices
Authors: Habtoor Omer Saeed , Ahmad Norsiah
Published: March 2017

This study focuses on Saudi’s unique social and cultural context and its impact on board attributes and corporate risk disclosure (CRD) by addressing the relationship between royal family members on the board and CRD. Using content analysis of a sample of 307 company-year observations over the period of 2008-2011, the results from the descriptive statistics show a moderate level of CRD practices among firms. The initial and additional results from the panel data analysis show that board characteristics, namely, board size, board independence, royal family members on the board, and meeting frequency of the board of directors are important determinants of CRD in Saudi Arabia. The positive influence of royal family members on CRD in this study contradicts the classic negative relationship between family members on the board and disclosure, which indicates that not all types of families’ members on the board have the same motivation towards corporate disclosure.
Fractional optimal control problem for differential system with control constraints
Authors: Bahaa G.M.
Published: March 2017

In this paper, the fractional optimal control problem for differential system
is considered. The fractional time derivative is considered in
Riemann-Liouville sense. Constraints on controls are imposed. Necessary and
sufficient optimality conditions for the fractional Dirichlet and Neumann
problems with the quadratic performance functional are derived. Some
examples are analyzed in details.
Reciprocal product-degree distance of graphs
Authors: Su Guifu , Xiong Liming , Gutman Ivan , Xu Lan
Published: March 2017

We investigate a new graph invariant named reciprocal product-degree
distance, defined as: RDD* = ?{u,v}?V(G)u?v deg(u)?deg(v)/dist(u,v)
where deg(v) is the degree of the vertex v, and dist(u,v) is the distance
between the vertices u and v in the underlying graph. RDD* is a
product-degree modification of the Harary index. We determine the connected
graph of given order with maximum RDD*-value, and establish lower and upper
bounds for RDD*. Also a Nordhaus-Gaddum-type relation for RDD* is obtained.
Gastric sarcoidosis
Authors: Kasikovic-Lecic Svetlana , Vucinic Violeta , Panjkovic Milana , Kukic Biljana
Published: March 2017

Introduction. Sarcoidosis is a systemic disease with a 90% predilection for the lungs, but any organ can be involved. Gastric sarcoidosis may be a component of a generalized process, while isolated gastric sarcoidosis is very rare. Case Outline. We describe a rare case of biopsy-proven gastric sarcoidosis in a 45-year-old woman with pulmonary sarcoidosis in remission, and highlight the importance of gastroscopy and biopsy to confirm the diagnosis. Her optimal response to anti-acid therapy required no alternate (glucocorticoid) therapy. We briefly review the clinical, diagnostic, and therapeutic aspects of gastric sarcoidosis. Conclusion. Glucocorticoids remain the cornerstone of the sarcoidosis treatment, although it has been insufficiently documented by clinical trials. The decision to treat sarcoid patients with systemic glucocorticoids is largely based upon the severity of symptoms. The anti-acid therapy may be an alternative in milder cases, as demonstrated in our patient.
Oral complications in irradiated head and neck cancer patients - 3D conformal radiotherapy planning vs. 3D conformal radiotherapy planning with magnetic resonance fusion
Authors: Latinovic Miroslav , Mitric-Askovic Milana , Ivanov Olivera , Novakovic Mico , Licina Jelena
Published: March 2017

Introduction/Objective. The incidence of radiation-induced side effects in patients with head and neck (H&N) cancer depends on the planning technique and the irradiation dose, as well as primary tumor location within the H&N region. The aim of our research is to establish the incidence of side effects in patients with H&N cancer treated with conformal radiotherapy planning with computed tomography (CT) or computed tomography fusion with magnetic resonance imaging (CT-MRI fusion). Methods. Prospective analysis was performed on 40 patients with oropharynx carcinoma and on 40 patients with larynx carcinoma prospectively followed after radiotherapy. Forty patients with H&N cancer were irradiated by using 3D conformal radiotherapy planning with CT, while other 40 patients were treated using 3D conformal radiotherapy planning with CT-MRI fusion. In all cases standard fractionation was used at 2 Gy per day, five days a week. Results. Of the total of 80 patients treated, 52 patients (52/80; 65%) reported a side effect and the incidence of complications was higher in patients irradiated with 3D technique planning with CT (31/52; 60% for 3D CT vs. 21/52; 40% for 3D CT-MRI; p = 0.02). There were more complications in chemoradiotherapy group of patients than observed when only radiotherapy was used ? 35/52 RT + HT vs. 17/52 RT (67%: 33% and p = 0.004). Conclusion. 3D radiotherapy technique planned solely on the basis of CT is related to high incidence of toxicity, which significantly affects the quality of life of irradiated patients. 3D conformal radiotherapy planned with CT-MRI fusion reduces the incidence of oral complications. Following the example of developed countries, this technique should be considered as a standard method for irradiating patients with H&N cancer. Planning technique with fusion technique using MR imaging is more suitable for delivering higher doses to the tumor with fewer side effects.
Experimental study of solidification of paraffin wax in solar based triple concentric tube thermal energy storage system
Authors: Ravi Rengarajan , Rajasekaran Karunakaran
Published: March 2017

This paper addresses an experimental investigation of a solar based thermal energy storage system to meet current energy demand especially for milk industry in Tamil Nadu, India. A solar based energy storage system has been designed to study the heat transfer characteristics of paraffin wax where it is filled in the middle tube, with cold heat transfer fluid flowing outer tube, inner tube, and both tubes at a time during solidification process in a horizontal triple concentric heat exchanger. In this study, main concentrations are temperature distributions in the energy storage materials such as paraffin wax during solidification process and total solidification time. Three heat recovery methods were used to solidify paraffin wax from the inside tube, outside tube, and both tubes methods to improve the heat transfer between heat transfer fluid and phase change materials. The experiment has been performed for different heat transfer fluid mass-flow rates and different inlet temperatures and predicted results shows that solidification time is reduced.
Approximate analytical solution for 1-D problems of thermoelasticity with dirichlet condition
Authors: Almazmumy Mariam , Bakodah Huda , Al-Zaid Nawal , Ebaid Abdelhalim , Rach Randolph
Published: March 2017

This paper presents the solution of the initial boundary-value problem for the system of 1-D thermoelasticity using a new modified decomposition method that takes into accounts both initial and boundary conditions. The obtained solution is based on the generalized form of the inverse operator and is given in the form of a finite series. Also, some numerical experiments were presented to the both the effectiveness and the accuracy of the presented method.
Cone-beam computed tomography evaluation on the changes in condylar long axis according to asymmetric setback in sagittal split ramus osteotomy patients
Authors: Lim Sun-Young , Jiang Tingting , Oh Min-Hee , Kook Min-Suk , Cho Jin-Hyoung , Hwang Hyeon-Shik
Published: March 2017

Objective: To determine whether the condylar rotation is affected by asymmetric setback in patients undergoing sagittal split ramus osteotomy.

Materials and Methods: Thirty patients who underwent bilateral sagittal split ramus osteotomy setback surgery were divided into the two groups, symmetric setback and asymmetric setback, according to the right/left difference of setback amount (<2.0, ≥2.0 mm). Condylar long axis changes were evaluated using the three-dimensional superimposition of before and immediately after surgery cone-beam computed tomography volume images. Evaluations were performed separately in lesser setback and greater setback side in patients undergoing asymmetric setback, whereas both side condyles were evaluated together in patients undergoing symmetric setback. Condylar axis changes on axial view were correlated with setback amount or right/left setback difference using Pearson correlation analysis.

Results: In general, the condylar axis change occurred in a pattern of inward rotation. The condyles in patients undergoing symmetric setback showed 3.4° rotation in average. In case of asymmetric setback, the lesser setback side showed larger value (4.3°) than the greater setback side (2.3°) with a statistical significance. In the correlation analysis, setback amount showed no significant correlation with the condylar axis changes in both groups. However, correlation with right/left setback difference showed a positive correlation in lesser setback side of patients undergoing asymmetric setback.

Conclusion: The findings of this study indicate that large amount of setback alone does not contribute to the change in condylar long axis, but asymmetric setback might cause a change in condylar long axis, particularly on the lesser setback side.
Ceramic Veneers for Esthetic Restoration of Retained Primary Teeth: A 4-year Follow-up Case Report
Authors: Bin-Shuwaish MS
Published: March 2017

Retained primary teeth in the smile zone can cause patient dissatisfaction, especially if associated with malposition of teeth. Orthodontic and prosthetic treatment options to treat the situation may not be accepted by some patients. Therefore, these patients tend to maintain their primary teeth and seek different esthetic options. Ceramic veneers may provide an esthetic treatment option to restore these teeth. However, the survival rates of ceramic restorations in such cases have not yet been established. This case report provides a step-by-step clinical description of the use of ceramic veneers for the restoration of retained primary canines and mild teeth malalignment, with a 4-year follow-up report, in a 28-year-old female patient. During restorative treatment, an effort was made to maintain the occlusion in group function to minimize stress and eliminate destructive forces on the retained primary teeth. After 4 years of function, the patient was still satisfied with the provided treatment.
INFILTRATION of SHIA: SEGMENTATION of AL-DAKHIIL in INTREPRETATION of AL-MISHBAH
Authors: Nur Afrizal
Published: March 2017

M.Quraish Shihab is the Indonesian contemporary Muffassir, since he is capable and too bold to convey the message of the Qur’an that’s contextualized with the current situation which makes him popular, but at the same time his popularity started dropping as his pro-Shia views and interpretation, this has caused controversy among public. Shia infiltration is a segmentation of al-Dakhiil in the interpretation of the Koran, which is about the following issues: the cult of the Prophet Muhammad’s daughter (Fatima ra), Ali bin Abi Talib ra is First People who substitute the Prophet, believer in verse 105 of al-Tawbah letter are special people and Ahlul Bait. Among criticisms, there were always directed to the professor in Qur’an Tafseer at UIN Syarif Hidayatullah Jakarta is a rational interpretation in some cases above, because it is so memorable to his figures of contemporary Shi’ism. Hopefully, this article is as an effort to repair and may contribute to restore al-tafseer book of Mishbah commentary be dignified and highvalue tafseer equivalent to the works of previous commentary of Indonesian Mufassir
STUDI HADIS-HADIS MUKHTALIF TENTANG MENGUMUMKAN KEMATIAN (AL-NA’Y)
Authors: Adynata Adynata
Published: March 2017

Hadis merupakan sumber ajaran Islam kedua setelah al-Quran. Dalam memahaminya diperlukan ilmu-ilmu tertentu agar tidak terjadi kekeliruan, sebab hadis-hadis tersebut kadang kala terlihat bertentangan satu sama lain, padahal jika hadis itu sahih bersumber dari Rasulullah SAW maka mustahil terjadi pertentangan padanya. Oleh karena itu, para ulama hadis mengkaji jenis hadis ini dan merumuskan metode penyelesaiannya dengan sebuah ilmu yaitu Ilmu Mukhtalif al-Hadis. Di antara permasalahan yang terjadi di sebagian masyarakat yang berkaitan dengan kesalahan memahami hadis mukhtalif adalah tentang mengumumkan kematian (al-na’y) antara hadis yang membolehkan dan melarang. Kedua versi hadis tentang mengumumkan kematian (al-na’y) tersebut terlihat bertentangan satu sama lain atau mukhtalif yang mesti dipahami berdasarkan metode Ilmu Mukhtalif al-Hadis. Pada hadis yang melarang al-na’y, Rasulullah SAW. menyebutkan alasan atau illat pelarangan itu, yakni tindakan mengumumkan kematian seperti yang dilakukan oleh orang-orang Jahiliyah. Sedangkan pada hadis yang membolehkan al-na’y di mana Rasulullah SAW. dan sahabatnya melakukannya tidak mengandung tata cara Jahiliyah, tetapi sebaliknya mengandung kemaslahatan yang banyak. Oleh karena itu, pelarangan al-na’y itu terkait dengan tata caranya, yaitu tata cara Jahiliyah, Berdasarkan kajian ini, dapat disimpulkan bahwa sesungguhnya kedua versi hadis tersebut tidaklah bertentangan
KELUAR DARI ALIENASI ALAM TERHADAP MANUSIA Perspektif Teosofi Transenden
Authors: Cinu Surahman
Published: March 2017

Alam yang dihuni oleh manusia makin rusak parah, akibat ulah manusia, apakah ini yang dikhawatirkan malaikat saat mereka berdialog dengan Tuhan,“ tidak cukupkan kami (malaikat) ya Tuhan sebagai pengabdi kepadaMu, sehingga engkau akan menciptakan manusia yang kerjanya akan membuat kerusakan dimuka bumi”. Sekali lagi Tuhan menampakkan substansi absolutnya, “Sesungguhnya Aku lebih mengetahui daripada kalian”’ Mereka selanjutnya tunduk pada perintah Tuhan dengan cara “sujud” (kecuali Iblis) dihadapan Adam, dimana keturunannya, atas dasar ketidak puasan mengeksploitas sekaligus merusak alam semesta
ORIENTALIST CRITICISM TO QIRA’AT MUTAWATIRAH AND DEFENSE (A FACT AND REALITY)
Authors: Bin Mohd Saad Mohd Faizulamri , Nur Afrizal
Published: March 2017

Qira’at mutawatirah is the word of Allah. It is the source and the most important element in the studying al-Qur’an. It is a primary reference source, in its capacity as al-Qur’an revealed by Allah SWT. But the problem that arises is when some scientists and orientalists attempt to criticize Qira’at mutawatirah and embroider it with misconceptions. This condition becomes worse, because it was found from critical that refused accuracy of Qira’at mutawatirah by concluding Qira’at mutawatirah is wrong. Based on the statement above, this paper will discuss and analyze about the views that criticize Qira’at mutawatirah to explain the reasoning-defense argument. This study is a qualitative research and focused on documents analysis. The findings of this study concluded that the arguments defense Qira’at mutawatirah is a strong argument, while criticism argued is not correct, because their consideration simply put human logic of the word of Allah SWT
Influence of Chemically Synthesized Electro-Conductive Additive in the Positive Electrode on Electrochemical Performance of the Lead-Acid Batteries
Authors: Murali Gadipudi , Kosaraju Sreenivas , KSN Murthy , Mandava Jagadish
Published: March 2017

The basic objective of the present work is to study the effect of chemically synthesized polyaniline (PANI) as an electronically conductive additive on the positive active material properties and its influence on the performance, functional characteristics of lead-acid battery has been studied. The mechanisms contributing to the formation of both lead dioxide and additional conductive nanostructured cross-linking channels by the introduction of this additive is described. The structure and morphology of pure PANI and respective electrode samples have been studied using XRD (X-ray diffractometer) and SEM (scanning electron microscopy) images.
Introduction
Authors: Jarnicki Paweł , Lang Sandra
Published: March 2017

Introduction to the Dossier - Ludwik Fleck’s Theory of Thought Styles and Thought Collectives:  Translations and Receptions
Tadeusz Bilikiewicz’s Background in the Debate with Ludwik Fleck
Authors: Koterski Artur
Published: March 2017

One of the factors that adversely influenced the worldwide reception of Fleck was the rather narrow critical interest that his ideas had aroused in Poland. Apart from a few reviews of his book (1935), only two polemics were published before WWII, and these likewise fell into oblivion. The philosophical views of one of those polemists, Tadeusz Bilikiewicz, shared the same fate. Since an acquaintance with Bilikiewicz’s background would seem to be a necessary condition for a (full) understanding of his controversy with Fleck, the aim of this paper is to sketch his views on the history and sociology of science, and to clarify certain errors regarding the facts of his life.
Ludwik Fleck’s reception in Brazil
Authors: Condé Mauro L.
Published: March 2017

The main purpose of this article is to provide a type of general framework of Ludwik Fleck’s reception in Brazil. Although this is not strictly a review of Fleck’s work – what I did in some papers before – we can use some of Fleck’s concepts to understand how his ideas have spread in Brazil. In other words, how was the genesis and development of Fleck’s thought-style in different thought collective in Brazil.
Corrosion resistance and mechanical properties of quenched and tempered 28MnCrB5 steel in two acidic environments
Authors: Yazıcı Aysel , Zeybek M. Sadrettin , Güler Hüseyin , Pınar Ahmet Murat , Tücer Renas
Published: March 2017

Microstructure, hardness distribution, tensile properties and fracture behavior of the quenched and tempered steel 28MnCrB5 were investigated before and after corrosion tests. The corrosion behavior of the quenched and tempered steel 28MnCrB5 was examined in two different acidic environments, namely a hydrochloric acid solution and fertilizer-containing soil. The specimens were immersed in corrosive environments for 24, 48, 72, 96, 120, 144 and 168 hours, and additionally into fertilizer-containing soil for 240 days. The corrosion losses were determined by measuring the weight changes and the respective corrosion rates were calculated. Ductile fracture was observed in the sample of the quenched and tempered material before and after 168 hours of exposure to the hydrochloric acid solution and fertilizer-containing soil environment. But, in the sample subjected to corrosion in the fertilizer-containing soil environment for 240 days, brittle fracture took place and the fracture topography on the surface exhibited inter-granular cleavage. After 240 days of corrosion test in the fertilizer-containing soil environment, the ductility of the material decreased to a very great extent. The surface of the quenched and tempered 28MnCrB5 samples was covered by corrosion pits, cracks and peelings at the end of 168 h tests in the hydrochloric acid solution environment. At the end of 240 day tests in the fertilizer-containing soil environment, the surface of the samples showed deep peelings and cracks.
Statistical analysis of burst requirements from regulations for composite cylinders in hydrogen transport
Authors: Becker Ben , Mair Georg W.
Published: March 2017

Existing standards for the approval of composite cylinders in the transport of compressed hydrogen are currently based on deterministic (ISO 11119-3) and semi-probabilistic (UN GTR No. 13) criteria. This paper analyzes the behavior of these procedures with respect to the evaluation of burst strength. Their characteristics are compared with the probabilistic approach developed at BAM. Based on Monte-Carlo simulations, the available design range (mean value and scatter of burst strength) of all concepts are assessed. In addition, the probability of acceptance for potentially unsafe design types is determined. Due to current approval criteria, the results show large areas of burst properties with a sufficient reliability which cannot be used for the design of composite cylinders. On the other hand, existing standards allow the approval of potentially unsafe designs in case of a very high scatter regarding their burst strength. It is also shown that existing design types are already designed to the limits of the available design area. A further weight and cost reduction of composite cylinders is closely related to the approval criteria. An example based on UN GTR No. 13 shows how an approval criterion can be optimized by using statistical methods. The example shows that a reduced minimum burst pressure can be combined with a lower probability of acceptance for potentially unsafe design types.
Mechanical behavior of internal pressurized composite pipes jointed with embedded tubular sleeves
Authors: Sülü İsmail Yasin
Published: March 2017

In this paper, composite pipes bonded with embedded tubular sleeve subjected to internal pressure were analyzed by using the three dimensional finite element method (FEM). In the analysis, the composite pipes and sleeves are made of carbon/epoxy (AS4/3501-6) with different fiber orientation angles and DP 410 is the adhesive. The shear extension coupling of composite pipe and patch was considered because the lay-up angles with +θ and –θ layers were in different radii. The models for the numerical analyses were generated by using the ANSYS software package. The finite element analyses (FEA) were carried out to predict the failure loads. Radial, tangential, axial and shear stress values were obtained via numerical analyses on composite pipes and adhesive layers. In addition, the von Mises stress distributions on the adhesive were obtained. Consequently, the effects of orientation angles, overlap widths and adhesive layer were examined. The most effective parameters were determined for composite pipes adhesively bonded with embedded tubular sleeve.
Flashing Method for Fabricating Micro Scale Fibers, Spheres, Porous and Condensed Polymer Structures
Authors: Porwal R. , Bellare J. R.
Published: March 2017

Micro and nano structures have unique properties such as large specific surface area, high porosity and smaller diameter size. They have several potential applications in textile industries, filtration systems and biomedicine. Common methods employed for fabrication of nanofibers include electrospinning, force spinning, biocomponent spinning and melt blowing. Flashing provides an easy method to produce discrete fibers from higher molecular weight polymers. Its production rate is also high compared to conventional methods, making it an attractive technique. Experiments were performed using the flashing method in which a polymer is dissolved in a suitable solvent at supercritical conditions of temperature and pressure. Then, the formed homogeneous solution was extruded through a nozzle at high speed into a zone of substantially lower temperature and pressure. Polyethylene terephthalate was used as the polymer while dichloromethane and Freon 12 were the solvents. By changing various parameters in the experiment, a variety of structures such as micro scale fibers, spheres, porous structures as well as condensed irregular structures were obtained. Further, ESEM, cryo FEG SEM and porosity measurements were carried out on the samples obtained to study their external and internal structures. We have identified morphological phase space of this system so that the microstructure can be tuned to the desired state based on process parameters.
Design Guidelines to Balance the Flow Distribution in Complex Profile Extrusion Dies
Authors: Rajkumar A. , Ferrás L. L. , Fernandes C. , Carneiro O. S. , Becker M. , Nóbrega J. M.
Published: March 2017

In this work a novel methodology to balance the flow distribution in complex extrusion dies is proposed. For this purpose, the profile cross section geometry is divided into simpler geometries (L and T shaped profiles), which are balanced with a surrogate model obtained by a detailed numerical study. The numerical simulations are performed considering the non-isothermal flow of Bird-Carreau inelastic fluids, and the numerical computations are performed with a solver implemented in OpenFOAM computational library. The proposed methodology is assessed with some case studies.
A novel method of lengthening the accessory nerve for direct coaptation during nerve repair and nerve transfer procedures
Authors: Tubbs R. Shane , Maldonado Andrés A. , Stoves Yolanda , Fries Fabian N. , Li Rong , Loukas Marios , Oskouian Rod J. , Spinner Robert J.
Published: March 2017

OBJECTIVE

The accessory nerve is frequently repaired or used for nerve transfer. The length of accessory nerve available is often insufficient or marginal (under tension) for allowing direct coaptation during nerve repair or nerve transfer (neurotization), necessitating an interpositional graft. An attractive maneuver would facilitate lengthening of the accessory nerve for direct coaptation. The aim of the present study was to identify an anatomical method for such lengthening.

METHODS

In 20 adult cadavers, the C-2 or C-3 connections to the accessory nerve were identified medial to the sternocleidomastoid (SCM) muscle and the anatomy of the accessory nerve/cervical nerve fibers within the SCM was documented. The cervical nerve connections were cut. Lengths of the accessory nerve were measured. Samples of the cut C-2 and C-3 nerves were examined using immunohistochemistry.

RESULTS

The anatomy and adjacent neural connections within the SCM are complicated. However, after the accessory nerve was “detethered” from within the SCM and following transection, the additional length of the accessory nerve increased from a mean of 6 cm to a mean of 10.5 cm (increase of 4.5 cm) after cutting the C-2 connections, and from a mean of 6 cm to a mean length of 9 cm (increase of 3.5 cm) after cutting the C-3 connections. The additional length of accessory nerve even allowed direct repair of an infraclavicular target (i.e., the proximal musculocutaneous nerve). The cervical nerve connections were shown not to contain motor fibers.

CONCLUSIONS

An additional length of the accessory nerve made available in the posterior cervical triangle can facilitate direct repair or neurotization procedures, thus eliminating the need for an interpositional nerve graft, decreasing the time/distance for regeneration and potentially improving clinical outcomes.
Association between bicortical screw fixation at upper instrumented vertebra and risk for upper instrumented vertebra fracture
Authors: Park Young-Seop , Hyun Seung-Jae , Choi Ho Yong , Kim Ki-Jeong , Jahng Tae-Ahn
Published: March 2017

OBJECTIVE

The aim of this study was to investigate the risk of upper instrumented vertebra (UIV) fractures associated with UIV screw fixation (unicortical vs bicortical) and polymethylmethacrylate (PMMA) augmentation after adult spinal deformity surgery.

METHODS

A single-center, single-surgeon consecutive series of adult patients who underwent lumbar fusion for ≥ 4 levels (that is, the lower instrumented vertebra at the sacrum or pelvis and the UIV of the thoracolumbar spine [T9–L2]) were retrospectively reviewed. Age, sex, follow-up duration, sagittal UIV angle immediately postoperatively including several balance-related parameters (lumbar lordosis [LL], pelvic incidence, and sagittal vertical axis), bone mineral density, UIV screw fixation type, UIV PMMA augmentation, and UIV fracture were evaluated. Patients were divided into 3 groups: Group U, 15 patients with unicortical screw fixation at the UIV; Group P, 16 with bicortical screw fixation and PMMA augmentation at the UIV; and Group B, 21 with bicortical screw fixation without PMMA augmentation at the UIV.

RESULTS

The mean number of levels fused was 6.5 ± 2.5, 7.5 ± 2.5, and 6.5 ± 2.5; the median age was 50 ± 29, 72 ± 6, and 59 ± 24 years; and the mean follow-up was 31.5 ± 23.5, 13 ± 6, and 24 ± 17.5 months in Groups U, P, and B, respectively (p > 0.05). There were no significant differences in balance-related parameters (LL, sagittal vertical axis, pelvic incidence–LL, and so on) among the groups. UIV fracture rates in Groups U (0%), P (31.3%), and B (42.9%) increased in sequence by group (p = 0.006). UIV bicortical screw fixation increased the risk for UIV fracture (OR 5.39; p = 0.02).

CONCLUSIONS

Bicortical screw fixation at the UIV is a major risk factor for early UIV compression fracture, regardless of whether a thoracolumbosacral orthosis is used. To reduce the proximal junctional failure, unicortical screw fixation at the UIV is essential in adult spinal deformity correction surgery.
Bronchodilatory effect of Myxopyrum serratulum in animal model
Authors: Maruthamuthu Vijayalakshmi , Kandasamy Ruckmani
Published: March 2017

The plant Myxopyrum serratulum is traditionally claimed to relieve asthma and cough. The present study was undertaken to evaluate the bronchodilatory effect of the methanolic extract of M. serratulum on histamine-induced bronchospasm by in vivo and the inhibitory effect of the extract on histamine-contracted tracheal chain and ileum by in vitro guinea pig model. Additionally, the relaxant effect of four cumulative concentrations of the extract (0.25, 0.5, 0.7 and 1.0 g%) was assessed using precontracted tracheal chain under different conditions. The extract (400 mg/kg) prolonged the preconvulsive time to 102.3 ± 3.8 sec when compared to saline and standard chlorpheniramine maleate as 121.3 ± 4.5 sec (p<0.05). The extract also possessed significant inhibitory effect on histamine-contracted guinea pig ileum and tracheal chain and also exhibited significant relaxation effect on precontracted tracheal chain of guinea pig models contracted by 60 mM KCl (p<0.001) and 10 µM methacholine (p<0.001) when compared with standard theophylline.
Apertureless near-field optical microscopy
Authors: Kazantsev D V , Kuznetsov E V , Timofeev S V , Shelaev A V , Kazantseva E A
Published: March 2017

We discuss the operating principles of the apertureless scanning near-field optical microscope (ASNOM), in which the probe acts as a rod antenna and its electromagnetic radiation plays the role of the registered signal. The phase and amplitude of the emitted wave vary depending on the ‘grounding conditions’ of the antenna tip at the sample point under study. Weak radiation from a tiny (2–15 μm long) tip is detected using optical homo- and heterodyning and the nonlinear dependence of the tip polarizability on the tip–surface distance. The lateral resolution of ASNOMs is determined by the tip curvature radius (1– 20 nm), regardless of the wavelength (500 nm–100 μm). ASNOMs are shown to be capable of providing a surface optical map with nanometer resolution and carrying out spectral- and time-resolved measurements at a selected point on the surface.
CFD Study of a New Annular Lift Fan Configuration with High Lift Efficiency
Authors: Jiang Yun , Zhang Bo
Published: March 2017

A new annular lift fan configuration that has very high lift efficiency is explored by using a numerical scheme. The inlet lip radius and diffuser angle are maximized by semicircle duct walls and the location of the lift fan is moved from the throat to the diffuser area to maximize the diffusion effect of the ducted fan. The improved lift fan achieves the figure of merit of 0.772 and the power loading of 9.03 lbs/hp without ground effect, very close to the theoretical limit. Under the ground effect, the figure of merit reaches 0.822 with the power loading of 9.62 lbs/hp. The improved lift efficiency deteriorates the transition characteristics with higher momentum drag and pitching moment. However, with the aid of jet thrusts directly providing part of the lift during transition, the peak of momentum drag and pitching moment can be lowered. A total thrust to weight ratio of 0.7 is enough for all of the requirements in transition and in hover and for the maximum speed of 0.75 Mach in cruise flight.
The Effects of Wet Compression by the Electronic Expansion Valve Opening on the Performance of a Heat Pump System
Authors: Seong Kyoungjin , Lee Daehui , Lee Jinho
Published: March 2017

In this study, by controlling the Electronic Expansion Valve opening, the influence of wet compression on a heat pump system was experimentally investigated in different heating conditions. The results demonstrate that the discharge temperature decreased and the mass flow rate increased, due to quality of the rising liquid droplets. It was also found that the heating capacity and power input of wet compression increased more than that of dry compression, with a superheat of 10 °C. The maximum COP (Coefficient of Performance) exists at a specific quality of ca. 0.94 to 0.90, as the power input in the region of wet compression is proportionally larger than the increase in the heating capacity, according to the decreasing quality. When the Entering Water Temperature of the Outdoor Heat Exchanger was 10 °C, 5 °C, and 0 °C, the COP increased by a maximum of ca. 12.4%, 10.6%, and 10.2%, respectively, in comparison to the superheat of 10 °C. In addition, the superheat at the discharge line is proposed as a proper controlling parameter to adjust the quality at the suction line, by varying the opening of the expansion valve during wet compression.
Polymerization of Alkylsilanes on ZIF-8 to Hierarchical Siloxane Microspheres and Microflowers
Authors: Yang Lin , Xie Congjia , Li Yizhou , Guo Lei , Nie Minfang , Zhang Jinping , Yan Zhiying , Wang Jiaqiang , Wang Wei
Published: March 2017

The use of metal-organic frameworks (MOFs) in the polymerization field remains comparatively rare up to now, let alone studies on the fabrication of polymer microstructures through a MOFs-catalyzed assembly process. Zeolitic imidazolate framework-8 (ZIF-8), a well-known MOF for its chemical and thermal stabilities, was used to induce a polymerization reaction of saturated alkylsilanes for the first time. The reaction temperature was found to be critical for morphology control of the polymerized ZIF-siloxane composites. The polymerization of alkylsilanes by ZIF-8 at room temperature resulted in siloxane microspheres while rose petal-like microstructures were obtained at higher temperature. The effects of the reaction time on the structures of the polymerization products were also investigated and the polymerization reaction process was proposed. This work expands the field of MOFs’ applications and develops a reasonable method for the multidimensional assembly of MOFs building blocks into required structures or platforms for designing new kinds of hierarchical morphologies, which to our knowledge has not been previously investigated.
Effect of a Magnetic Quadrupole Field on Entropy Generation in Thermomagnetic Convection of Paramagnetic Fluid with and without a Gravitational Field
Authors: Shi Er , Sun Xiaoqin , He Yecong , Jiang Changwei
Published: March 2017

Entropy generation for a paramagnetic fluid in a square enclosure with thermomagnetic convection is numerically investigated under the influence of a magnetic quadrupole field. The magnetic field is calculated using the scalar magnetic potential approach. The finite-volume method is applied to solve the coupled equation for flow, energy, and entropy generation. Simulations are conducted to obtain streamlines, isotherms, Nusselt numbers, entropy generation, and the Bejan number for various magnetic forces (1 ≤ γ ≤ 100) and Rayleigh numbers (104 ≤ Ra ≤ 106). In the absence of gravity, the total entropy generation increases with the increasing magnetic field number, but the average Bejan number decreases. In the gravitational field, the total entropy generation respects the insensitive trend to the change of the magnetic force for low Rayleigh numbers, while it changes significantly for high Rayleigh numbers. When the magnetic field enhances, the share of viscous dissipation in energy losses keeps growing.
Tunable-Q Wavelet Transform Based Multivariate Sub-Band Fuzzy Entropy with Application to Focal EEG Signal Analysis
Authors: Bhattacharyya Abhijit , Pachori Ram , Acharya U.
Published: March 2017

This paper analyses the complexity of multivariate electroencephalogram (EEG) signals in different frequency scales for the analysis and classification of focal and non-focal EEG signals. The proposed multivariate sub-band entropy measure has been built based on tunable-Q wavelet transform (TQWT). In the field of multivariate entropy analysis, recent studies have performed analysis of biomedical signals with a multi-level filtering approach. This approach has become a useful tool for measuring inherent complexity of the biomedical signals. However, these methods may not be well suited for quantifying the complexity of the individual multivariate sub-bands of the analysed signal. In this present study, we have tried to resolve this difficulty by employing TQWT for analysing the sub-band signals of the analysed multivariate signal. It should be noted that higher value of Q factor is suitable for analysing signals with oscillatory nature, whereas the lower value of Q factor is suitable for analysing signals with non-oscillatory transients in nature. Moreover, with an increased number of sub-bands and a higher value of Q-factor, a reasonably good resolution can be achieved simultaneously in high and low frequency regions of the considered signals. Finally, we have employed multivariate fuzzy entropy (mvFE) to the multivariate sub-band signals obtained from the analysed signal. The proposed Q-based multivariate sub-band entropy has been studied on the publicly available bivariate Bern Barcelona focal and non-focal EEG signals database to investigate the statistical significance of the proposed features in different time segmented signals. Finally, the features are fed to random forest and least squares support vector machine (LS-SVM) classifiers to select the best classifier. Our method has achieved the highest classification accuracy of 84.67% in classifying focal and non-focal EEG signals with LS-SVM classifier. The proposed multivariate sub-band fuzzy entropy can also be applied to measure complexity of other multivariate biomedical signals.