scholarly journals Improvement of upsetting process of four-beam workpieces based on computerized and physical modeling

2020 ◽  
Vol 48 (4) ◽  
pp. 946-953
Author(s):  
Oleg Markov ◽  
Volodymyr Kukhar ◽  
Vitalii Zlygoriev ◽  
Alexander Shapoval ◽  
Anton Khvashchynskyi ◽  
...  
Keyword(s):  
Cross Section ◽  
Physical Modeling ◽  
Experimental Investigations ◽  
Relative Depth ◽  
Longitudinal Cross Section ◽  
Internal Defect ◽  
Compressive Stresses ◽  
A Value ◽  
Mean Stresses

The method of upsetting of large ingots has been investigated in this work. The proposed method consists in upsetting of profiled workpieces with concave faces. An angle of the concave faces was 150°. A relative depth of the concave faces has been varied in range 15%…25% from workpiece's diameter. Strains effective and mean stresses in the longitudinal cross-section of the workpiece with concave faces after upsetting have been determined by FEM. A value of compressive stresses has been determined based on a parameter of the stress state. FEM allowed to find what a rational depth of the concave faces should be, which has to be 15 % from workpiece's diameter. Maximum closing of the internal defect take place for this depth of the concave faces. Results of the FEM have been tested by experimental investigations. It has been established that upsetting of the four-beam workpieces improved a quality of the massive parts.

Performance Improvement Of Shrink-Fitted Assemblies by Surface Strengthening

1992 ◽  
Vol 206 (3) ◽  
pp. 207-213 ◽  
Author(s):  
B Ramamoorthy ◽  
V Radhakrishnan
Keyword(s):  
Performance Improvement ◽  
Testing Machine ◽  
Experimental Investigations ◽  
Ball Burnishing ◽  
Surface Strength ◽  
Interference Fit ◽  
Surface Strengthening ◽  
Compressive Stresses ◽  
Universal Testing

Interference fits are widely used in engineering applications. Many methods have been tried out to improve the strength of interference fits by improving the quality of the mating surfaces. An experimental investigation was carried out to study the strength of the assemblies after ball burnishing the shafts, which improves the surface finish and also imparts the surface strength by way of improving the hardness and residual compressive stresses. The assemblies were soaked for different duration times at elevated temperature and then the axial load-bearing tests were carried out in a Universal testing machine. The surface strengthening of shafts by burnishing and ageing of assemblies at high temperature resulted in considerable improvement of strength of the interference fit assemblies. This paper discusses the experimental investigations in detail and analyses the strength obtained from them.

Evaluation of the Properties of Humus Liquid of Earthworm Eisenia Foetida Obtained from Different Rachis

2017 ◽  
Vol 3 (02) ◽  
Author(s):  
Ramiro Remigio Gaibor Fernández ◽  
Abraham Adalberto Bayas Zamora ◽  
Galo Israel Muñoz Sánchez ◽  
Cristhian Adrián Rivas Santacruz
Keyword(s):  
Plant Growth ◽  
Fulvic Acids ◽  
Cattle Manure ◽  
Eisenia Foetida ◽  
Humic And Fulvic Acids ◽  
Livestock Manure ◽  
A Value ◽  
The One ◽  
Liquid Slurry

The objective of the present investigation was to evaluate the physical characteristics of the vermicompost and the quality of the purine of the red Californian (Eisenia foetida) using different substrates of feed for these worms. For this purpose, nine treatments were studied: 75% African palm rachis + 25% cattle manure, 50% African palm rachis + 50% cattle manure, 25% African palm rachis + 75% livestock manure, 50% manure of cattle, 50% of manure of cattle, 25% of manure of cattle, 50% of manure of cattle, 50% of manure of cattle, 50% of rach of coconut + 50% of manure of Livestock, 25% coccus rachis + 75% livestock manure. The substrate made up of 50% of rachis of coconut and 50% of livestock manure can be used in nurseries or nurseries for being the one that registered a value of pH 7.3 plus the closest to the neutral compared to the others, besides this (75% of oil palm rachis and 25% of cattle manure) showed a higher content of humic and fulvic acids (0.87 and 0.45 p / p, respectively), compounds that are important for agriculture by stimulating plant growth, in addition to this reflection 0.06% sulfur content, 4.0 ppm boron, 7.0 ppm copper, 47.5 ppm iron, 6.0 ppm manganese, with a presence of microorganisms of the species Trichoderma, Penicillium, Cladosporium sp. in amounts of 1.91x105 UFC / ml, however in this substrate was obtained between 13.3 and 43.5% less liquid slurry in Comparison with other treatments.

DAYA SAING EKSPOR PRODUK CPO INDONESIA DAN POTENSI HILIRISASI DIOLAH MENJADI BIODIESEL

2020 ◽  
Vol 4 (2) ◽  
Author(s):  
Danar Agus Susanto
Keyword(s):  
Palm Oil ◽  
Comparative Advantage ◽  
Global Market ◽  
National Standard ◽  
Revealed Comparative Advantage ◽  
Crude Palm Oil ◽  
A Value ◽  
World Demand ◽  
Domestic Use

ABSTRACTIndonesia is the world's largest producer of crude palm oil (CPO). Even so, the trend of international trade in Indonesian CPO products has decreased in the last 10 years with a value of -10.19%. The decline in world demand for CPO can be dealt with by utilizing CPO as a biofuel for domestic use, like biodiesel. The purpose of this study is to determine the competitiveness of Indonesian CPO in global trade and determine the parameters of the quality requirements of CPO and biodiesel. The competitiveness analysis method uses the Revealed Comparative Advantage (RCA) method, while the analysis of the potential quality of CPO as a biofuel is carried out by analyzing the Indonesian National Standard (SNI). CPO trade in the global market is controlled by Indonesia with a market share of 50% and Malaysia 25.6%, with the declining trade trend in the last 10 years relatively (2010-2019) of -6.91%. The level of competitiveness of Indonesian CPO products in 2019 is very strong, but on average in the last 10 years, the level of competitiveness of Indonesian CPO is no better than that of Malaysia. Indonesia has SNI 01-2901-2006 and SNI 7182: 2015 as a determinant of the quality of CPO and biodiesel products developed in Indonesia so that the CPO and biodiesel produced fullfil sacurity and safety aspects when used by consumers.Keywords: crude palm oil (CPO), competitivenessv, quality, Indonesian National Standard (SNI) ABSTRAKIndonesia merupakan negara produsen minyak kelapa sawit mentah/ Crude Palm Oil (CPO) terbesar di dunia. Meskipun demikian, tren perdagangan internasional produk CPO Indonesia mengalami penurunan dalam sepuluh tahun terakhir dengan nilai -10,19%. Penurunan permintaan dunia terhadap CPO, dapat disiasati dengan memanfaatkan CPO sebagai bahan bakar nabati untuk keperluan dalam negeri sebagai biodiesel. Tujuan penelitian ini adalah mengetahui daya saing CPO Indonesia dalam perdagangan global dan mengetahui parameter persyaratan mutu CPO dan biodiesel. Metode analisis daya saing menggunakan metode Revealed Comparative Advantage (RCA), sedangkan analisis potensi kualitas CPO sebagai biofuel dilakukan dengan menganalisis Standar Nasional Indoensia (SNI). Perdagangan CPO dalam pasar global dikuasai oleh Indonesia dengan pangsa pasar 50% dan Malaysia 25,6%, dengan tren perdagangan relatif menurun dalam 10 tahun terakhir (2010-2019) sebesar -6,91%. Tingkat daya saing produk CPO Indonesia pada tahun 2019 sangat kuat, namun secara rata-rata dalam 10 tahun terakhir, tingkat daya saing CPO Indonesia tidak lebih baik dari Malaysia. Indonesia memiliki SNI 01-2901-2006 dan SNI 7182:2015 sebagai penentu kualitas produk CPO dan biodiesel yang dikembangkan di Indonesia, sehingga CPO dan biodiesel yang dihasilkan memenuhi aspek keamanan dan keselamatan ketika digunakan oleh konsumen.Kata kunci: crude palm oil (CPO), daya saing, kualitas, Standar Nasional Indonesia (SNI)

The effectiveness of a digital pelvic floor training program in thetreatment of urinary incontinence – a real-world evaluation (Preprint)

2019 ◽  
Author(s):  
Sabine Keim ◽  
Alexandra von Au ◽  
Lina Maria Matthies ◽  
Stephanie Wallwiener ◽  
Sarah Brugger ◽  
...  
Keyword(s):  
Urinary Incontinence ◽  
Pelvic Floor ◽  
University Hospital ◽  
First Line ◽  
First Line Therapy ◽  
A Value ◽  
Pelvic Floor Training ◽  
Significant Impairment ◽  
Pelvic Floor Weakness

BACKGROUND Background: Many women experience urinary incontinence (UI) during andafter pregnancy due to pelvic floor weakness. First-line therapy is conservative treatment, which nowadays can be facilitated by using digitalsolutions. OBJECTIVE The aim ofthe present study was to investigate the efficacy and effectiveness of pelvinain patients with existing UI. METHODS Methods: In the present observational study we analyzed the effectivenessof pelvina, a certified digital pelvic floor training course, in reducing UI symptoms by regularly applying “The Questionnaire for Urinary Incontinence Diagnosis” (QUID) and furthermore examining quality of life (QoL) by conducting the SF-6D. RESULTS Results: In this prospective study, 373 patients with a median age of 36 years (IQR 33 - 47 years) were included. At baseline the patients had a median QUID of 11 (IQR 11 - 15). During the course, incontinence improved significantly to a QUID of 5 (IQR 2 – 11; p<0.001). Additionally, the patients had also shown a significant impairment in their QoL at baseline with a value of 19 (IQR 16 - 22) in SF-6D. After completing the course, the QoL had risen to 24 (IQR 20 - 26). CONCLUSIONS Conclusion: Use of the certified digital pelvic floor course pelvinasignificantly reduces existing UI due to pelvic floor weakness over the timespan of the course. At the same time QoL is significantly improved. CLINICALTRIAL The present study was approved by the ethics committee of the Heidelberg University Hospital (S-392/2019)

scholarly journals Machining Ti-6Al-4V Alloy Using Nano-Cutting Fluids: Investigation and Analysis

2021 ◽  
Vol 5 (2) ◽  
pp. 42
Author(s):  
Abdelkrem Eltaggaz ◽  
Ibrahim Nouzil ◽  
Ibrahim Deiab
Keyword(s):  
Surface Finish ◽  
Minimum Quantity Lubrication ◽  
Weight Fraction ◽  
Contact Length ◽  
Al2o3 Nanoparticles ◽  
Compressive Stresses ◽  
Cutting Zone ◽  
The Impact ◽  
Cooling And Lubrication

Minimum Quantity Lubrication nanofluid (MQL-nanofluid) is a viable sustainable alternative to conventional flood cooling and provides very good cooling and lubrication in the machining of difficult to cut materials such as titanium and Inconel. The cutting action provides very difficult conditions for the coolant to access the cutting zone and the level of difficulty increases with higher cutting speeds. Furthermore, high compressive stresses, strain hardening and high chemical activity results in the formation of a ‘seizure zone’ at the tool-chip interface. In this work, the impact of MQL-nanofluid at the seizure zone and the corresponding effects on tool wear, surface finish, and power consumption during machining of Ti-6Al-4V was investigated. Aluminum Oxide (Al2O3) nanoparticles were selected to use as nano-additives at different weight fraction concentrations (0, 2, and 4 wt.%). It was observed that under pure MQL strategy there was significant material adhesion on the rake face of the tool while the adhesion was reduced in the presence of MQL-nanofluid at the tool-chip interface, thus indicating a reduction in the tool chip contact length (TCCL) and reduced seizure effect. Furthermore, the flank wear varied from 0.162 to 0.561 mm and the average surface roughness (Ra) varied from 0.512 to 2.81 µm. The results indicate that the nanoparticle concentration and the reduction in the seizure zone positively influence the tool life and quality of surface finish.

693. A rejection test for raw milk

1958 ◽  
Vol 25 (1) ◽  
pp. 32-51 ◽  
Author(s):  
Peggy B. Taylor ◽  
L. F. L. Clegg
Keyword(s):  
Lactic Acid ◽  
Ferric Chloride ◽  
Technical Assistance ◽  
Milk Proteins ◽  
Raw Milk ◽  
Ph Change ◽  
Yellow Colour ◽  
A Value ◽  
Keeping Quality

The determination of apparent lactic acid has been used as a basis for a rejection test for raw milk. The method consists of precipitation of milk proteins with barium chloride, sodium hydroxide and zinc sulphate, and the addition of ferric chloride to the filtrate to produce the yellow colour of ferric lactate. Lactic acid is not solely responsible for the production of the yellow colour, which, nevertheless, gives a good relationship with keeping quality of milk (measured as hours to the C.O.B. end-point at 22° C.) and the values have been expressed as ‘apparent lactic acid’.The relationship of winter and summer milks to keeping quality has been studied, and a value of 0·03% apparent lactic acid in milk is equivalent to an average keeping quality of 5¾ and 8½ hr. for winter and summer milks, respectively. A value of 0·03% is recommended as the earliest value of apparent lactic acid at which milk could be rejected.The apparent lactic acid in colostrum and late-lactation milk and in milk from cows suffering from mastitis has been determined, and only in late-lactation milk were the values found to be significantly higher than usual in fresh raw milk, and an inverse relationship between yield and apparent lactic acid is suggested.Permanent glass matching disks have been prepared for use in a Lovibond comparator. This permits the intensity of the yellow colour produced with 1% ferric chloride to be determined and the apparent lactic acid in milk estimated.Grateful acknowledgement is made to the management and staff of the Dairy Department of the Reading Co-operative Society and the Farmer's Clean Milk Dairy, Reading, and local milk producers for supplying samples for experiments; to the N.M.T.S. staff in Reading for help in finding suitable farmers, and to the Dairy Husbandry Department of the N.I.R.D. for information about and samples of abnormal and late-lactation milk. Our particular thanks are due Miss Marie Gruber for technical assistance, to Dr N. J. Berridge for the suggestion and help on the work on pH change as an indication of keeping quality (given in the appendix), and to Dr A. T. R. Mattick for the advice given in this work.

A transverse and longitudinal cross-section separation in a π+ electroproduction coincidence experiment and the pion radius

1977 ◽  
Vol 120 (1) ◽  
pp. 45-61 ◽  
Author(s):  
G. Bardin ◽  
J. Duclos ◽  
A. Magnon ◽  
B. Mitchel ◽  
J.C. Montret
Keyword(s):  
Cross Section ◽  
Longitudinal Cross Section ◽  
Coincidence Experiment

ANALYSIS OF MENTAL WORKLOAD WITH INTEGRATING NASA TLX AND FUZZY METHOD

JOURNAL ASRO ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 37
Author(s):  
Riono Riono ◽  
Suparno Suparno ◽  
Adi Bandono
Keyword(s):  
Evaluation System ◽  
Mental Workload ◽  
Work Load ◽  
Mental Work ◽  
Fuzzy Method ◽  
A Value ◽  
Factor Evaluation ◽  
Nasa Tlx ◽  
Territorial Water

ABSTRAK In carrying out its main duty as a guardian of the territorial water sovereignty republic Indonesia, the strength of the Navy is directed as a strategic force developed under the SSAT. The strength of the Navy can be measured by the arsenal and the quality of the personnel who are responsible for it. The performance, quality of personnel is strongly influenced by the work load it receives. Measurement of personnel workload in Indonesian Warship to determine the class of his current position using the Factor Evaluation System (FES) method that is more oriented on the volume of work and work time. While the mental workload has not been accommodated in the measurement of workload using this method. In this research will carry out the measurement of mental workload of Indonesian Warship personnel for each type of work when the Indonesian Warship operates, using the NASA TLX method integrated with the Fuzzy method. The questionnaire data collection was obtained from 82 respondents Indonesian Warship personnel. From the research results obtained data that of 11 (eleven) types of work in Indonesian Warship at the time of operation, Main Engine Operators work is the work that has the highest mental workload with a value of 74.33. While the type of work that most low-level mental work is to electronics Operators with a value of 58.83.  Keywords: Workload, NASA TLX, FUZZY Method, FES

The interaction of kinks and elastic waves

1962 ◽  
Vol 266 (1325) ◽  
pp. 222-246 ◽  
Keyword(s):  
Energy Density ◽  
Cross Section ◽  
Elastic Waves ◽  
String Model ◽  
Zero Point ◽  
Radiation Reaction ◽  
Point Energy ◽  
A Value ◽  
Ordinary Point ◽  
Isotropic Elastic Medium

A kink on a dislocation in an isotropic elastic medium is treated as a 'point defect’ with a certain mass, constrained to move along a line and subject to a radiation reaction. A value for the mass is obtained from the well know n stretched-string model, and the radiation reaction is found by calculating the rate at which an oscillating kink radiates energy into the medium . It is found that the kink has a scattering cross-section for elastic waves which i§ proportional to the square of its width. For long waves the cross-section is independent of frequency, in contrast to the case of ordinary point defects. A kink moving through an isotropic flux of elastic waves experiences a retarding force proportional to the product of its velocity and the energy density of the waves. In connexion with a similar result for the retarding force on a dislocation moving rigidly it has been suggested that the expression for the energy density should include the zero-point energy. A formal quantum -mechanical calculation shows that this is not so in the case of a kink.

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