Garuda - Garba Rujukan Digital

Article Per Year (5 Year)

All

Journal of Engineering and Technological Sciences

JETS
Website

Published by Institut Teknologi Bandung

ISSN : 23375779 EISSN : 23385502 DOI : -

Core Subject : Engineering,

Engineering

Journal of Engineering and Technological Sciences welcomes full research articles in the area of Engineering Sciences from the following subject areas: Aerospace Engineering, Biotechnology, Chemical Engineering, Civil Engineering, Electrical Engineering, Engineering Physics, Environmental Engineering, Industrial Engineering, Information Engineering, Mechanical Engineering, Material Science and Engineering, Manufacturing Processes, Microelectronics, Mining Engineering, Petroleum Engineering, and other application of physical, biological, chemical and mathematical sciences in engineering. Authors are invited to submit articles that have not been published previously and are not under consideration elsewhere. Starting from Vol. 35, No. 1, 2003, full articles published are available online at http://journal.itb.ac.id, and indexed by Scopus, Index Copernicus, Google Scholar, DOAJ, GetCITED, NewJour, Open J-Gate, The Elektronische Zeitschriftenbibliothek EZB by University Library of Regensburg, EBSCO Open Science Directory, Ei Compendex, Chemical Abstract Service (CAS) and Zurich Open Repository and Archive Journal Database. Publication History Formerly known as: ITB Journal of Engineering Science (2007 â€“ 2012) Proceedings ITB on Engineering Science (2003 - 2007) Proceedings ITB (1961 - 2002)

Arjuna Subject : -

Articles 1,267 Documents

36 37 38 39 40

Parameter Estimation for Class A Modeled Ocean Ambient Noise Zhang, Xuebo; Ying, Wenwei; Yang, Bo
Journal of Engineering and Technological Sciences Vol 50, No 3 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

A Gaussian distribution is used by all traditional underwater acoustic signal processors, thus neglecting the impulsive property of ocean ambient noise in shallow waters. Undoubtedly, signal processors designed with a Gaussian model are sub-optimal in the presence of non-Gaussian noise. To solve this problem, firstly a quantile-quantile (Q-Q) plot of real data was analyzed, which further showed the necessity of investigating a non-Gaussian noise model. A Middleton Class A noise model considering impulsive noise was used to model non-Gaussian noise in shallow waters. After that, parameter estimation for the Class A model was carried out with the characteristic function. Lastly, the effectiveness of the method proposed in this paper was verified by using simulated data and real data.

Analysis of Stress State of Bolts under Different Anchorage Qualities Zeng, Sheng; Zhou, Jie; Sun, Bing; Wen, Xia
Journal of Engineering and Technological Sciences Vol 50, No 3 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

A series of pull-out tests were conducted in order to study the stress states of bolts under different anchorage qualities and to simulate the influence of quality defects in empty-slurry and low-strength mortar anchorage in actual engineering. The tests mainly investigated strain characteristics at different positions of the bolts and the effects of strains at the same positions under different anchorage conditions. The research led to the following conclusions: (1) under ultimate bearing capacity, the strain values decayed the fastest along the length of the bolt in the full-length anchorage, the strain values decayed the slowest in the empty-slurry and low-strength mortar anchorage, and the decaying speed of strains in the empty-slurry mortar anchorage was between that of the above two kinds of anchorages; (2) at almost 50% of the ultimate bearing capacity, the strain values were slightly different between the empty-slurry and low-strength mortar anchorage and the empty-slurry anchorage. Obvious differences in strain values occurred when the bolts were continued to be loaded. The strain values of the full-length anchorage bolts were different from those of the other two kinds of anchorages; (3) from the analysis of stress variation characteristics, the safety reserve was the highest for the full-length anchorage under the condition of ultimate bearing capacity, followed by the empty-slurry mortar anchorage, while the safety reserve was the lowest for the empty-slurry and low-strength mortar anchorage. However, in terms of uniformity of force and utilization of the material, the result was reverse.

Vibration Parameter Optimization of a Linear Vibrating Banana Screen Using DEM 3D Simulation Wu, Xiaoqiu; Li, Zhanfu; Xia, Huihuang; Tong, Xin
Journal of Engineering and Technological Sciences Vol 50, No 3 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

In this paper, the effects of vibration parameters of a banana screen, i.e. frequency, amplitude and vibration direction angle, on the screening efficiency per unit time were studied using the discrete element method (DEM). The simulations were validated according to data collected from an experimental prototype screen. Functional relationships between vibration parameters and screening efficiency per unit time are presented. The results showed that the screening efficiency per unit time first displays an increase and later a decrease when the frequency, amplitude or vibration direction angle increased respectively. Vibration parameter optimization was also investigated, using an orthogonal experiment. Based on the banana screen model, it can be concluded that when the frequency is 22 Hz, the amplitude is 2.2 mm and the vibration direction angle is 39Â°, the screening efficiency of a banana screen is optimal.

Application of RBFNNs Incorporating MIMO Processes for Simultaneous River Flow Forecasting Tripura, Joseph; Roy, Parthajit; Barbhuiya, Abdul Karim
Journal of Engineering and Technological Sciences Vol 50, No 3 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

Simultaneous flow forecasting using multi-input multi-output (MIMO) processes is an efficient technique for accurate flow forecasting on river systems. The present study demonstrates the capability of radial basis function neural networks (RBFNN) incorporating MIMO processes in simultaneous river flow forecasting. The river system considered in the present study was the Barak river system, Assam, India. Hourly concurrent discharge data were collected from the Central Water Commission, Shillong, India from multiple sections of the Barak river system. The forecasts were tested for short-range time horizons, i.e. 1, 3, 6 and 12 hours in advance, and a comparative analysis was done using the popular Nonlinear Autoregressive with Exogenous Inputs (NARX) time series model. The result shows that MIMO-NARX provided higher prediction accuracy than MIMO-RBFNN, even at longer lead times when compared to following various statistical criterions.

Land Cover and Climate Change Impact on River Discharge: Case Study of Upper Citarum River Basin Kuntoro, Arno Adi; Cahyono, Muhammad; Soentoro, Edy Anto
Journal of Engineering and Technological Sciences Vol 50, No 3 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

The Upper Citarum River Basin is the main catchment area of the Saguling Dam, the most upstream of three cascade dams in the Citarum River Basin. During the last 30 years, rapid economic development has led to an increase of water extraction and land conversion from green area to developed area. Also, evidence of climate change can clearly be seen from the climatological records of a number of climatology stations in this basin over the last few decades. In this study, the effect of anthropogenic and climate change in the Upper Citarum River Basin river discharge was simulated using the Sacramento Catchment Model. Historical river discharge, rainfall, climatology, and land cover from 1995 to 2009 were used for model calibration and verification. The multi-model mean monthly rainfall and the temperature projection taken from Coupled Model Intercomparison Project 5 (CMIP5) for the RCP6 and RCP8.5 climate change scenarios were statistically downscaled and used as input for a simulation of future river discharge from 2030 to 2050. The result showed that the combination of anthropogenic and climate change may result in a significant decrease of low flow in the Upper Citarum River Basin. This study underlines the importance of land cover and climate change factors for future infrastructure planning and management in the Upper Citarum River Basin.

Experimental Assessment of Various Batteries and Propellers for Small Solar-Powered Unmanned Aerial Vehicle Rajendran, Parvathy; Smith, Howard
Journal of Engineering and Technological Sciences Vol 50, No 3 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

In this study, the performance of the propulsion system of a solar-powered unmanned aerial vehicle (UAV) was investigated. Both battery and propeller variation tests were performed to evaluate their performance in relation to an electric motor. The battery was varied in the number of cells and capacity, and the propeller was varied in terms of diameter, pitch, manufacturer, and propeller type (fixed and folding propellers). For validation, the bench test result was compared with a simulation model. The bench test provided a reasonable guide for the throttle level required to obtain optimal power. A large variation existed in propeller performance between manufacturers. Sizing electric propulsion is important for UAV performance and the manufacturing factor is significant for propeller performance.

Prediction of Service Life Decline of Double Welded Wide Flanges due to Fatigue in Steel Arch Bridge under Excessive Loads Noor, Rusandi; Asnan, Muhammad Noor
Journal of Engineering and Technological Sciences Vol 50, No 3 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

The purpose of this study was to investigate the characteristics of the rate of fatigue fracture propagation in members under maximum force on a steel arch bridge and to identify the fatigue life of those members under excessive loads. The method for bridge fatigue prediction used was numerical S-N curve controlled by cumulative damage rule, fracture critical member, and fatigue fracture determination based on SNI 1729-2015, S-N category. The distribution of stress, strain and life cycle was obtained. The result revealed 1 critical built-up weld beam on the steel arch bridge, specifically double welded wide flange beam TB7. Excessive loads from heavy vehicles, namely trailer types 7C1, 7C2 and 7C3, were simulated. Initial fracturing would occur after 53 years and 5 months of service with an initial crack size of 1.717 mm, leading to a propagation cycle of 45 years, which would cause critical fractures of 10.55 mm after 99 years. Thus, the maximum number of vehicles permitted to enter the bridge, assuming a 5% increase per year, was 13,450 per year for trailer type 7C3 at a planned capacity of 6,984,000 vehicles. This paper illustrates how fatigue life prediction can be a useful guide for the sustainability of bridges and provide a theoretical basis for developing optimized fatigue life of steel arch bridges.

Numerical Simulation on the Influence of Bridge Construction on River Flood Control in a Bottleneck Reach Han, Jianqiao; Wang, Honglei; Luo, Han; Duan, Wenzhong
Journal of Engineering and Technological Sciences Vol 50, No 4 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

Bottleneck reach regions with narrow and deep cross sections prevent sediment transport and weaken flood control capacity. In addition, bridge constructions can exacerbate the risk of flooding in these areas. In this study, the Longhai Railway Extension Project at the Xianyang reach of the Weihe River in China was selected as a typical object. A horizontal 2-D numerical model was used to assess the effects of three engineering plans on flood discharge capacity under three flood frequencies. Plan 1 was designed to include building a new bridge, demolishing the three original bridges and dredging a single section of the channel. Plan 2 was the same as Plan 1, except for the compound sections. Plan 3 was designed with the four bridges coexisting and no dredging projects carried out. The results indicated that Plan 3 will increase the water level by 0.2-0.3 m in the upstream reach. The cross-sectional area was approximately 370 m2 larger under Plan 1 than under Plan 2. Water levels of 300-, 100-, and 5-year flooding around the bridge were reduced by 0.9, 0.9, and 0.6 m, respectively. To improve flood control capacity, an effective dredging project must be executed to widen the river and reduce the water stage in the bottleneck reach where the bridge is constructed.

Advancement in the Analysis of Seepage through Cracked Soils Krisnanto, Sugeng; Rahardjo, Harianto
Journal of Engineering and Technological Sciences Vol 50, No 4 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

Seepage is an important problem analyzed in geotechnical engineering. Conventionally, the analysis is performed in conditions where the soil is intact. The presence of desiccated cracks requires a seepage analysis that considers not only the soil matrix part of the cracked soil but also the crack network. Currently, there are three approaches in the analysis of seepage through cracked soils: (i) analysis by modeling the cracked soil as an intact material with cracks being represented as macropores; (ii) analysis by modeling the cracked soil as a material with a bimodal pore-size distribution; and (iii) analysis by modeling two components of the cracked soil separately: the soil matrix and the crack network. Each approach is reviewed and discussed in this paper. It was found that each approach is suitable for specific cases: (i) the first method is suitable for seepage analysis of cracked soil deep below the ground surface; (ii) the second method is suitable for seepage analysis of cracked soil at the ground surface under a drying process; (iii) the third method is suitable for seepage analysis of cracked soil at the ground surface experiencing rainwater infiltration. Choosing the appropriate method is essential in modeling the appropriate seepage mechanism.

Effect of Nutrient Inputs on Water Quality Change and Phytoplankton Growth in Atsumi Bay Mahlil, Teuku; Inoue, Takanobu; Matsumoto, Yoshitaka; Aoki, Shinichi; Kato, Shigeru; Yokota, Kuriko; Rasul, Ernawaty; Saga, Makoto
Journal of Engineering and Technological Sciences Vol 50, No 4 (2018)
Publisher : ITB Journal Publisher, LPPM ITB

Eutrophication in an estuary occurs as an effect of the enrichment of nutrient inputs from rivers. This condition has become one of the most common environmental issues experienced around the globe and especially in Japan. Atsumi Bay is a eutrophic coastal area in Japan. The objective of this research was to analyze the influences of nutrient inputs from the Umeda River into Atsumi Bay on pre- and post-rainfall water quality conditions. This study was conducted from July to October 2010. The results showed a decrease of surface salinity after rainfall indicating that huge freshwater inputs had overlaid the surface layer of Atsumi Bay rather than the bottom layer. Moreover, post-rainfall conditions showed an increase of chlorophyll a as an effect of phytoplankton growth, followed by an increase of particulate nutrients. On the other hand, dissolved nutrients decreased due to uptake by phytoplankton and dilution by freshwater.

Page 38 of 127 | Total Record : 1267

36 37 38 39 40

Filter by Year

2003 2023

Filter By Issues

All Issue Vol. 55 No. 6 (2023) Vol. 55 No. 5 (2023) Vol. 55 No. 4 (2023) Vol. 55 No. 3 (2023) Vol. 55 No. 2 (2023) Vol. 55 No. 1 (2023) Vol. 54 No. 6 (2022) Vol. 54 No. 5 (2022) Vol. 54 No. 4 (2022) Vol. 54 No. 3 (2022) Vol. 54 No. 2 (2022) Vol. 54 No. 1 (2022) Vol. 53 No. 6 (2021) Vol. 53 No. 5 (2021) Vol. 53 No. 4 (2021) Vol. 53 No. 3 (2021) Vol. 53 No. 2 (2021) Vol. 53 No. 1 (2021) Vol. 52 No. 6 (2020) Vol. 52 No. 5 (2020) Vol. 52 No. 4 (2020) Vol 52, No 3 (2020) Vol. 52 No. 3 (2020) Vol. 52 No. 2 (2020) Vol 52, No 2 (2020) Vol. 52 No. 1 (2020) Vol 52, No 1 (2020) Vol 51, No 6 (2019) Vol. 51 No. 6 (2019) Vol. 51 No. 5 (2019) Vol 51, No 5 (2019) Vol. 51 No. 4 (2019) Vol 51, No 4 (2019) Vol. 51 No. 3 (2019) Vol 51, No 3 (2019) Vol. 51 No. 2 (2019) Vol 51, No 2 (2019) Vol 51, No 2 (2019) Vol 51, No 1 (2019) Vol 51, No 1 (2019) Vol. 51 No. 1 (2019) Vol 50, No 6 (2018) Vol 50, No 6 (2018) Vol. 50 No. 6 (2018) Vol 50, No 5 (2018) Vol 50, No 5 (2018) Vol. 50 No. 5 (2018) Vol 50, No 4 (2018) Vol. 50 No. 4 (2018) Vol 50, No 4 (2018) Vol 50, No 3 (2018) Vol. 50 No. 3 (2018) Vol 50, No 3 (2018) Vol. 50 No. 2 (2018) Vol 50, No 2 (2018) Vol 50, No 2 (2018) Vol. 50 No. 1 (2018) Vol 50, No 1 (2018) Vol. 49 No. 6 (2017) Vol 49, No 6 (2017) Vol 49, No 6 (2017) Vol 49, No 5 (2017) Vol 49, No 5 (2017) Vol. 49 No. 5 (2017) Vol 49, No 4 (2017) Vol. 49 No. 4 (2017) Vol 49, No 4 (2017) Vol 49, No 3 (2017) Vol 49, No 3 (2017) Vol. 49 No. 3 (2017) Vol. 49 No. 2 (2017) Vol 49, No 2 (2017) Vol 49, No 2 (2017) Vol 49, No 1 (2017) Vol. 49 No. 1 (2017) Vol. 48 No. 6 (2016) Vol 48, No 6 (2016) Vol 48, No 6 (2016) Vol 48, No 5 (2016) Vol. 48 No. 5 (2016) Vol 48, No 5 (2016) Vol. 48 No. 4 (2016) Vol 48, No 4 (2016) Vol 48, No 3 (2016) Vol. 48 No. 3 (2016) Vol. 48 No. 2 (2016) Vol 48, No 2 (2016) Vol 48, No 1 (2016) Vol. 48 No. 1 (2016) Vol. 47 No. 6 (2015) Vol 47, No 6 (2015) Vol. 47 No. 5 (2015) Vol 47, No 5 (2015) Vol. 47 No. 4 (2015) Vol 47, No 4 (2015) Vol. 47 No. 3 (2015) Vol 47, No 3 (2015) Vol 47, No 2 (2015) Vol. 47 No. 2 (2015) Vol. 47 No. 1 (2015) Vol 47, No 1 (2015) Vol. 46 No. 4 (2014) Vol 46, No 4 (2014) Vol. 46 No. 3 (2014) Vol 46, No 3 (2014) Vol. 46 No. 2 (2014) Vol 46, No 2 (2014) Vol 46, No 1 (2014) Vol. 46 No. 1 (2014) Vol 45, No 3 (2013) Vol. 45 No. 3 (2013) Vol. 45 No. 2 (2013) Vol 45, No 2 (2013) Vol 45, No 1 (2013) Vol. 45 No. 1 (2013) Vol 44, No 3 (2012) Vol. 44 No. 3 (2012) Vol 44, No 2 (2012) Vol. 44 No. 2 (2012) Vol. 44 No. 1 (2012) Vol 44, No 1 (2012) Vol. 43 No. 3 (2011) Vol 43, No 3 (2011) Vol 43, No 2 (2011) Vol. 43 No. 2 (2011) Vol 43, No 1 (2011) Vol. 43 No. 1 (2011) Vol 42, No 2 (2010) Vol. 42 No. 2 (2010) Vol 42, No 1 (2010) Vol. 42 No. 1 (2010) Vol. 41 No. 2 (2009) Vol 41, No 2 (2009) Vol 41, No 1 (2009) Vol. 41 No. 1 (2009) Vol. 40 No. 2 (2008) Vol 40, No 2 (2008) Vol. 40 No. 1 (2008) Vol 40, No 1 (2008) Vol. 39 No. 2 (2007) Vol 39, No 2 (2007) Vol. 39 No. 1 (2007) Vol 39, No 1 (2007) Vol 38, No 2 (2006) Vol. 38 No. 2 (2006) Vol 38, No 1 (2006) Vol. 38 No. 1 (2006) Vol 37, No 2 (2005) Vol. 37 No. 2 (2005) Vol 37, No 1 (2005) Vol. 37 No. 1 (2005) Vol. 36 No. 2 (2004) Vol 36, No 2 (2004) Vol. 36 No. 1 (2004) Vol 36, No 1 (2004) Vol 35, No 2 (2003) Vol. 35 No. 2 (2003) Vol. 35 No. 1 (2003) Vol 35, No 1 (2003) More Issue

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kota bandung,

Jawa barat

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name -

Contact Email -

Phone -

Journal Mail Official -

Editorial Address -

Location Kota bandung, Jawa barat INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kota bandung,

Jawa barat

INDONESIA