bluuebunny/crossref_metadata_2025 huggingface dataset:
An Historical Study of The Ministry of Federal Territories building in Putrajaya within the Perspective of the Discourse on the National Architectural Identity of Administrative Architecture
Authors: Rasdi Mohd Tajuddin Mohd , Kanesh Kavin , Utaberta Nangkula , Asif Nayeem
Published: February 2020

With the establishment of a new administrative center in Putrajaya, an opportunity to address and to reaffirm a national architectural identity was presented. This research attempts to document and evaluate the design direction of administrative buildings in Putrajaya in response to the issue of establishing a national architectural identity. It will attempt to analyze the various inputs towards achieving the desired image, from the political, socio cultural as well as economic context. Additionally, it is crucial to understand the architectural identity thoughts and standpoint of the architect that was in charge of the design and implementation of the selected administrative building. This research uses a historical architectural interpretative methodology to analyze the building in place and aided with literature reviews, interviews with the relevant persons involved as well as on site direct observation and analysis of the building involved. The data obtained and presented reveals the thoughts that were the basis of forming the national architecture identity to an extent. The architect’s position in relation to achieving the design-brief but at the same time, utilizing his or her reflection and background formation. The research discovers that the architect’s design principles were to emphasize the local and Islamic characteristics to highlight the role of Islam within the new administrative center of Malaysia. The resulting outcome of this research will provide an understanding on how to critically engage in addressing architectural issues that form a national architecture identity.
Knowledge, attitude and practice on occupational safety and health among workers in petrochemical companies
Authors: Mukhtar Mohd Yasir Mohd , Yusof Afzan Mat , Isa Muhammad Lokman Md
Published: February 2020

Petroleum, petrochemical or oil and gas industry is one of the important industrial sectors in Malaysia. The safety in the workplace is one of the vital issues that need to be taken seriously. Every worker should know about the occupational safety and health organization to protect them from any accidents and injuries. The purpose of this study was to determine the level of knowledge, attitude and practice on occupational safety and health among workers in petrochemical companies at Teluk Kalung Industrial Area, Kemaman, Terengganu. A cross-sectional study was conducted among the workers in petrochemical companies. A convenience sampling method was used to collect the data. Descriptive statistics was used to describe the levels of knowledge, attitude and practice (KAP) among the workers. Chi-square test were used to test the association between level of knowledge with level of attitude, level of knowledge with level of practice and level of attitude with level of practice. From the study, it found that there was significant association between level of knowledge with level of attitude (p=0.002), no significant association between knowledge level and practice level (p=0.386) and was no significant difference between the level of attitude and the level of practice (p=0.117). Therefore, this study found that the knowledge level can significantly affect the attitude level of the workers. Training on occupational safety and health should be held to improve their knowledge and attitude. It is recommended for other researcher to extend this study to other places with same industrial sector as there were few studies of knowledge, attitude and practice on occupational safety and health in petrochemical companies conducted.
A study of clean water distribution network development at PDAM Tirta Barito in the city of Buntok
Authors: Wahyu Diana Eka , Sholichin Mohammad , Haribowo Riyanto
Published: February 2020

PDAM of the City of Buntok is the supplier of clean water needs for the areas of Buntok Kota, Hilirsper, and Jelapat Hamlets and Pamait Village. Population growth, water loss and utilization of discharge that has not been optimal have become obstacles in service. The aim of the research is to evaluate the existing distribution network and development plan until 2038 as viewed from the aspect of hydraulics and water quality using WaterCAD v8i software, as well as economic analysis to determine water prices. The available discharge is 10, 000 l/s. Simulation of the existing condition produces pressure and headloss gradient that meet technical requirements, while velocity did not meet technical criteria. Water requirements for 2038 need an additional Water Treatment Plant with capacities of 30 l/s and 20 l/s. The simulation of development results met the technical requirements, being 0.3-4.5 m/s, a headloss gradient 0-15 m/km, and pressure of 0.5-8 atm. Further, the hydraulic model was used to analyse the concentration of residual chlorine. Injection at the tank inlet amounted to a constant 0.4 mg/l. Simulation of produced residual chlorine met the requirements from 0.383-0.395 mg/l. Economic analysis resulted in a water price of Rp. 6, 100.00/m3, BCR 1.23, IRR 12.14 %, and BEP of 11 years. Based on the willingness to pay being Rp. 4, 200.00/m3, the value of required government subsidies is Rp. 13, 905, 747, 800.
Safety evaluation of the existing Grawan dam based on hydro-geotechnical behaviour conditions to ensure the availability of water resources
Authors: Asmaranto Runi , Priyantoro Dwi , Yustika Rini Desy , Khurotul Aini Ayu
Published: February 2020

Grawan Dam was built in 2004 to supply irrigation water and raw water. Lately, the dam has experienced various symptoms of damage to the overflow structure due to hydraulic behaviour and the possibility of overtopping of the dam, which endangers the stability of the dam. Therefore, it is necessary to evaluate the overflow structure system based on the current hydrological conditions and to review the slope stability. In this study an evaluation was carried out covering the safety of the slopes as well as the safety of the overflow building system. Dam slope safety was reviewed based on seepage and slope stability. The stability of the overflow structure security system was evaluated in normal and earthquake conditions. The results of the hydrological analysis on guard height, seepage that occurs safely to permit discharge, and slope stability showed 100% safety from permitted safety factors, and on hydraulic conditions resulted in proposed improvements for Vlugter ponds, transition channels, and energy dampers with planning for Q100, Q1000, and QPMF. Analysis for the stability of the overflow structure showed that it is safe against rolling and sliding, and meets the eccentricity and carrying capacity of the soil, being 100% safe.
Flow structures in dividing open channels: a review
Authors: Ibrahim Izihan , Legori Ibrahim Saerahany , Khan Sheroz
Published: February 2020

The supply of water for human consumption starts with the abstraction of ‘raw’ water from various sources. Most of these facilities convey raw water by pumping it directly from rivers via lateral channels to nearby water treatment plants, but this is badly affected by debris and sediment clogging at the intake structures. Lateral intakes are actually special cases of river bifurcations, where the channel naturally divides into two different branches, each carrying part of the flow and sediment. Many researchers have completed studies on bifurcations/diversions to understand the behaviour of water flow and sediment transport. However, a complete understanding of the phenomenon, especially in relation to secondary flows and vortices, is lacking up to this day. In fact, if this can be overcome, it will greatly contribute to the fundamental study of hydrodynamics at asymmetric fluvial bifurcations as well as in optimal design of diversions. Thus, the distribution of water flow in both main and lateral channels requires further detailed investigation. A review of the current state of research is discussed in this paper, with the objective of identifying the grey areas and gaps specifically in the investigation of complex turbulent behaviour of flow structures in open channels with lateral diversions.
The effect of horizontal drainage on sediment water content in the spoilbanks of Sengguruh reservoir, Brantas river, Indonesia
Authors: Edy Sartono Sugik , Asmaranto Runi , Primantyo Hendrawan Andre
Published: February 2020

In the Brantas River System, Sengguruh is the first reservoir in the direction of the river flow. This reservoir functions to protect Sutami Reservoir from severe sedimentation. The effective storage capacity was about 24% of its initial storage. In order to restore the storage, dredging work at Sengguruh Reservoir must be carried out over the course of the year. To support the dredging, it is necessary to carry out technical work so that sediments in the temporary spoilbanks can be immediately hauled to another place and then are ready to be refilled. Hauling can be done optimally if the sediment condition in the spoilbanks is quite dry. Therefore, it is necessary to know how horizontal drainage can affect the sediment water content in the spoilbanks.
Mapping of drought distribution using the deciles index in Rokan Watershed, Province of Riau, Indonesia
Authors: Andawayanti Ussy , Dara Lufira Rahmah , Dyah Awalita Rizkina
Published: February 2020

Among natural hazards, droughts are known to cause extensive damage and affect a significant number of people. Droughts also have wide impacts across the economy, society, health, and education. This research is expected to be a reference to estimate the existence of droughts. After performing the calculation of drought indices, a drought distribution map was made using a Geographic Information System (GIS). The results showed that the worst drought occurred in 2013 to 2014. The average comparison between the discharge data and the level of decile data of both rain stations is 50%. It is evident that the discharge and decile-level data have good conformity. The result of the analysis, when associated with the incidence of El Nino, has a suitability of 32%, which could be due to other factors that affect rain conditions in the study location. Based on the results of the analysis of the annual trend of rainfall accumulation, the year when climate change initially occurred was in 2003. From 1990 to 2003 the drought distribution conditions tended to be “Dry” to “Very Dry”, whereas from 2003 to 2014 the drought-level distribution conditions were likely to be “Dry” to “Very Dry”.
Changes in government policies for regulating irrigation water in order to maintain food productivity
Authors: Azis Subandiyah , Wayan Mundra I
Published: February 2020

Global Warming has had an impact on climate change, which has caused disturbance to the availability of surface water and the change in the allocation of irrigation water for agriculture. The agricultural sector is a sector that is vulnerable to climate change. Therefore, the provision of irrigation water must be adapted to climate change so that the supply of irrigation water for agricultural land is well maintained to increase food production. The method used in completing this research is the descriptive method, involving observations during the rainy season, first dry season, and second dry season, soil tests at the research site, and disseminating improvements to the provision of irrigation water, so that irrigation water is more efficient in usage and distributed at the right time at the start of the rainy season, first dry season, and second dry season. In distributing questionnaires and providing understanding of the occurrences of climate change, almost all stakeholders have understood that the provision of irrigation water must be refined and adapted to climate change. Dissemination has been carried out to all stakeholders including the government and relevant agencies. The government promises to change the irrigation water regulation policy in order to maintain food productivity.
Two-dimensional numerical simulations of tsunamis on Puger beach, Jember
Authors: Kartini Lilik , Utami Agung Wiyono Retno , Denisio Edwin Rikarda Raden , Bagus Kurniawan Frendi , Halik Gusfan , Hidayah Entin , Bintang Pratama Munawir
Published: February 2020

On June 3, 1994, an earthquake located 200 km south of the island of Java triggered a devastating tsunami and caused losses of life and materials around beaches in the Jember, Lumajang, and Banyuwangi Regencies. It is highly important to study the process of tsunami occurrences, especially at Puger Beach, Jember. Thus, the main purpose of this study is to understand the mechanism of tsunamis in Puger Beach. Tsunami numerical simulation was performed using the Delft3D model to calculate the propagation of possible future tsunamis. Bathymetric data obtained from GEBCO_08 were utilized in this study. The tsunami model was validated using the survey data of the tsunami on June 3, 1994. Tsunami simulations were successfully performed in this study. From numerical simulations, it was shown that the fault model characteristics utilized in the model directly affected the tsunami height. Just after the initial surface elevation, the wave height decreased and the tsunami propagated at sea. As the wave propagated from offshore to shallower area, the tsunami height increased until reaching the maximum tsunami height in coastal areas such as Puger Beach. Tsunami mechanisms are clarified from both numerical simulations.
Effect of leaf inclination and rainfall intensity on the Canopy Wetness Index of Artocarpus Heterophyllus
Authors: Reza Kasury Ahmad , Sujono Joko , Jayadi Rachmad
Published: February 2020

Canopy characteristics have a significant influence on the process of canopy surface wetting and water canalization into the canopy reservoir. Canopy surfaces that have increased wetting until the canopy is saturated will describe the process of rainfall redistribution that occurs throughout the canopy. Canopy wetting until saturated or the canopy wetting index (β) is an indicator of rainfall redistribution by a canopy. Canopy reservoir filling can occur after the canopy surface per unit area has been completely saturated. This research was conducted with changes in rainfall intensity (R), leaf slope (α), canopy porosity, and canopy flow distribution (Tf) on Artocarpus heterophyllus. This study found that the rainfall redistribution process was strongly influenced by leaf characteristics, depth, and rainfall duration. Leaf characteristics, especially leaf inclination, will create a pattern of water canal from the canopy surface to the canopy reservoir. The leaf inclination characteristic will increase canopy wetting across the canopy surface simultaneously, but will not make water flow uniformly to the canopy reservoir.
Optimization of Water Distribution to Support the Balance of Water Usage: A Case Study of the Sempor Irrigation System, Central Java, Indonesia
Authors: Purwadi Hanugerah , Montarcih Limantara Lily , Suhartanto Ery , Rispiningtati
Published: February 2020

The existence of irrigation in Indonesia is commonly quite influenced by environmental and social cultural characteristics, which the people have lived by and developed for a long time. Many factors cause changes in the pattern of water availability, which increases competition among stakeholders, as in the Sempor irrigation system area. It has four main dams, which are the Bojong Dam, Watubarut Dam, Rowokawuk Dam, and Sindut Dam; it provides approximately 5900 ha of services and receives supplies from the Great Sempor Dam (38 million m3). Currently there is a decline in the function of this dam due to sedimentation, making operational services less optimal, especially during the dry season. The methodology of this study is to perform water optimization for the balancing of water in the irrigation area. Meanwhile, the implementation of the water supply on the field considers the calculation of water availability, space, and time. In practice, the operation of water supply is held by a group system in the secondary blocks. In certain conditions, the water rotation in tertiary channels was performed by local cultural wisdom.
Changes in Land Use in the Lombok River Basin and Their Impacts on River Basin Management Sustainability
Authors: Wiyono Wit Saputra Anggara , Azazi Zakaria Nor , Ngai Weng Chan
Published: February 2020

Sustainable management in water resources development strategies depends on the knowledge of phenomena of changes in land use in the river basin as a significant tool in understanding the interactions of environment and human activities. Changes that occur within a certain period on the land cover or land use impacts the basin characteristics, which will ultimately affect river basin management. This paper studies the change of land use in the Lombok river basin in Indonesia based on the Moderate Resolution Imaging Spectroradiometer (MODIS) land use/land cover data version 6 from the years of 2001, 2010, and 2016 which were derived using MODIS Terra and Aqua reflectance supervised classification data. Land use data was then classified into fifteen land use categories according to SWAT classification. QGIS and MapWindow software were applied to analyse the features of land use in the study area, and the SWAT simulation model was applied to simulate the impacts of changing land use in the sub-basin. The study concludes that areas with occurrences of changes in land use impacted the river runoff in the sub-basin. Analysis of river basin land use, when combined with simulation in water resources management, will contribute to optimal and sustainable river basin planning.
Sensitivity of methods for estimating potential evapotranspiration to climate change
Authors: Wayan Sutapa I , Saparuddin  , Wicana Satya
Published: February 2020

Global climate change occurs because of the addition of absorbing gases into the atmosphere, which can be interpreted as the greenhouse effect. Changes that occur in temperature will be followed by changes in other climatic elements, including rainfall, solar radiation, air humidity, and wind speed. The purpose of this study is to determine the sensitivity of potential evapotranspiration calculation methods to climate change and to determine the diversity of results based on differences in the calculation structure and the needed data. The utilized methods to estimate the sensitivity of potential evapotranspiration (ETp) to climate change were the Thornthwaite, Blaney-Criddle, FAO without correction, Makkink, Ivanov, Hargreaves-74, Modified Penman, and Penman-Monteith methods. The analysis was carried out using climate data from three climatological station locations in Central Sulawesi, which are the Singkoyo, Kulawi, and Bora Stations. The calculation results showed that the Thornthwaite and Blaney-Criddle methods were relatively the most sensitive to temperature changes, followed by the Penman-Monteith, Ivanov, Hargreaves 74, and Modified Penman methods. The FAO and Makkink methods showed relatively little sensitivity.
Monitoring the rainfall intensity at two active volcanoes in Indonesia and Japan by small-compact X-band radars
Authors: Syarifuddin Magfira , Indri Hapsari Ratih , Legono Djoko , Oishi Satoru , Ganara Mawanda Hanggar , Aisyah Nurnaning , Shimomura Makoto , Nakamichi Haruhisa , Iguchi Masato
Published: February 2020

Since 2015, collaborative research conducted by Indonesian and Japan scientists has initiated the installation of small X-band Multi-Parameter (X-MP) radars to mitigate the occurrence of rainfall-induced lahar in three active volcanoes in Indonesia and Japan: Merapi, Sinabung, and Sakurajima. This paper discusses the technical aspects of data acquisition, processing, and performance of the X-MP radar at the Merapi and Sakurajima volcanoes by comparing the estimated rainfall intensity acquired by the radar to three empirical radar-rainfall algorithms. The algorithms are based on radar reflectivity factor (ZHH), specific differential phase shift (KDP), and differential reflectivity (ZDR). A new method of Constant Altitude Plan Position Indicator (CAPPI) interpolation by linear regression is also proposed for a more efficient computation. The first algorithm by Marshall-Palmer, which relies on ZHH, gave the lowest average and maximum rainfall values compared with the other algorithms for all rainfall event cases. On the other hand, the other two algorithms, which involve the MP of radar by Bringi and Chandrasekar and Park et al., gave closer rainfall intensity values with the estimated rainfall intensity acquired by the X-MP radar. These three rain rates give a closer temporal fluctuation when they are compared to the rain gauge-based rainfall intensity.
Predictability of Naïve Bayes classifier for lahar hazard mapping by weather radar
Authors: Indri Hapsari Ratih , Ahida Indaka Sugan Bima , Novianto Dandung , Andrie Asmara Rosa , Oishi Satoru
Published: February 2020

The aim of this study is to develop lahar hazard vulnerability as a warning system by introducing radar-rainfall observation to data mining technique of Naïve Bayes Classifier (NBC). NBC is used to estimate lahar occurrences based on the posterior probability of rainfall, topographic factor, soil moisture, and soil type as predictors. Rainfall intensity and working rainfall were obtained from a weather radar. The soil moisture is derived from SMAP satellite imagery. A river on Mount Merapi, a very active volcano in Indonesia, was selected as the target basin. Observed rainfall and recorded lahar events in Gendol River from October 2016 to February 2018 were divided into a training dataset and a testing dataset. Qualitative evaluation through visual assessment of the hazard map product reveals that the model could estimate the occurrences of lahar. The performance of the model in terms of accuracy, Brier score, and quantitative dichotomous quality indices showed a reasonable skill. The study suggests that the NBC technique is advantageous for estimating lahar occurrences that are displayed on hazard maps. This work is expected to contribute to debris flow hazard mitigation by the data mining approach in volcanic regions.
Hydrodynamic simulation of a dam breach of Cipanas Dam using HEC-RAS 5.0.5
Authors: Iqbal Ikromi Akhmad , Nandi Wardhana Pradipta
Published: February 2020

Dams have many benefits for living creatures. On the other hand, dam breaks may also become disasters that cause potential losses of life and property. The Cipanas Dam has been planned for construction in Sumedang, West Java, and will have a storage capacity of up to 210 million m3. The area downstream of the Cipanas Dam contains many major infrastructures such as the Cikopo-Palimanan Toll Road and Kertajati International Airport that can be impacted by dam breach floods. This study analysed Cipanas Dam breach flow using HEC-RAS 5.0.5. The simulation assumed that a dam breach occurred through piping with 5 scenarios of breach time formation. The simulation resulted in flood hydrographs and flood inundation maps of the area downstream of the dam. The findings revealed that a breach formation time of 1 hour had the greatest flood effect. The maximum flood discharge was 38, 823.3 m3s-1 with a released water volume from the reservoir of 178, 814, 590 m3. The arrival time of the flood at the Cikopo-Palimanan Toll Road Bridge was 3 hours 45 minutes after the breach occurred, and the maximum flood depth was 15.78 m. Kertajati International Airport was not affected by the flood discharge.
Selective Fermentation and Prebiotic Index of Sago (Metroxylon sagu) Resistant Starches Type III by Rat Fecal Cultures
Authors: Zi-Ni T , Rosma A
Published: February 2020

One of the criteria for prebiotic substance is its selective fermentation by beneficial gut microbes. Previously, sago resistant starch type III (RS3) produced from Metroxylon sagu starch had been proven to resist digestion by gastrointestinal acidity and enzymes. In this research, sago RS3 was evaluated for its selective fermentation and prebiotic potential by fecal cultures. Sago RS3 was incubated with fecal microbial cultures for 72 hours at 37°C and samples were measured for microbial growth, prebiotic index, organic acid concentration and β-glucuronidase activity during the fermentation. Commercial prebiotics FOS (fructooligosaccharides) and inulin were used as comparison. Sago RS3 was selectively fermented by fecal beneficial lactobacilli and bifidobacteria while decreasing the growth of detrimental bacteroides, clostridia and enterobacteria. The prebiotic index of sago RS3, FOS and inulin was +12.19, +9.45 and +6.82, respectively. The butyric acid molar concentration in media with sago RS3 was comparable with FOS and inulin, and low activity of β-glucuronidase was detected in medium with sago RS3. Sago RS3 exhibited prebiotic characteristics comparable with commercial prebiotics and their potential prebiotic function is worth for further in vivo assessment.
Inhibition of Carbohydrate Hydrolysing Enzymes, Antioxidant Activity and Polyphenolic Content of Beilschmiedia Species Extracts
Authors: Tay Y N , Bakar M H A , Azmi M N , Saad N A , Awang K , Litaudon M , Kassim M A
Published: February 2020

The goal of the present study was to provide in vitro evidence for potential inhibition of carbohydrate hydrolysing enzymes and antioxidant activities of methanol and ethyl acetate extracts from barks of two different Beilschmiedia species. These extracts were tested on α-amylase and α-glucosidase inhibitory activities, mode of enzyme inhibition, total polyphenolic content (TPC) and antioxidant capabilities. Methanolic bark extract of Beilschmiedia insignis demonstrated optimum inhibitory effects against α-amylase and α-glucosidase with IC50 values of 3.233 µg/mL and 12.357 µg/mL, respectively. Further analysis of inhibition mode revealed that the extract demonstrated a mixed inhibition against both enzymes. In comparison to other extracts, methanolic bark extract of Beilschmiedia insignis demonstrated the highest TPC content of 420.393 mg GAE/g extract, lowest IC50 value of 12.103 µg/mL for DPPH radical scavenging ability and highest FRAP value of 1904.247 µM Fe (II)/mg extracts, indicating the antioxidant potential of the extract. A significant strong correlation coefficient was observed between TPC with FRAP (r = 0.994, p < 0.01) and TPC with DPPH (r = -0.860, p < 0.01), signifying that antioxidant activity and reducing capability were contributed by the polyphenolic compounds present in the crude extract. Collectively, methanolic bark extract of Beilschmiedia insignis possessed significant carbohydrate hydrolyzing enzyme inhibitory effects and antioxidant activity, suggesting its possible alternative application for diabetes and postprandial hyperglycemia treatment.
Preliminary study on the growth of Tetraselmis suecica in centred-light photobioreactor (CLPBR)
Authors: Serri N A , Anbalagan L , Norafand N Z , Kassim M A , Abu Mansor MS
Published: February 2020

Over the past decade, there has been a sustained research on renewable fuel known as biofuel due to the reliance upon fossil fuel. Oil obtained from microalgae is a viable approach for biodiesel production to reduce the reliability on fossil fuel. In this study, the Tetraselmis suecica is cultivated in 5L centred-light Photobioreactor (CLPBR) to investigate the effect of pH and light intensity on cell concentration and lipid content of microalgae. Different pH (6.5, 8.5, 10.5) and light intensity (200 lux, 1000 lux, 2000 lux) were used to test their effect on algal growth and lipid production. The results showed that the highest cell concentration (4 mL/mL) and lipid content (18 %) was obtained at pH of 10.5. At 1000 lux light intensity, the highest cell concentration and lipid content was 0.898 mL/mL and 19% respectively. The two models that are tested to determine the growth kinetics are Logistic and Gompertz model. The R2 obtained from Logistic and Gompertz model was 0.8852 and 0.8736 respectively. The results demonstrate that both models was least accurate to predict the algal growth.
Design and development of centred-light photobioreactor for microalgae cultivation system
Authors: Mustapa N S , Abu Mansor M S , Serri N A
Published: February 2020

The cultivation of microalgae within a controlled condition allows the production of biomass with lower contamination and suitable for high value pharmaceutical products. The controlled environment for microalgae growing can be accomplished by utilizing photobioreactor as a platform for introducing the basic needs needed by microalgae to grow effectively. However, due to some problems of high cost, low illumination and complicated cultivation systems which referring to available photobioreactors had contributed to low biomass production. This study deals with designing a new lab scale photobioreactor for overcoming the problems contributed by the available photobioreactors. During the developing process of the photobioreactor, the user needs are identified, and the most suitable concept based on the user needs was generated. The concept was then fabricated to prototype and its performance was validated. A centred-light photobioreactor was successfully developed for lab scale usage and being tested by cultivating Chlorella vulgaris species. A maximum of 0.281 g/L cell concentration was achieved using white light source during cultivation of Chlorella vulgaris.
Isolation and characterization of novel acidophilic microalgae from abandoned mining site area for carbohydrate biosynthesis and its kinetic growth study in photobioreactor
Authors: Tan K M , Kassim M A , Ng Z J , Lalung J
Published: February 2020

Microalgae have gained attention as an alternative feedstock for biofuel production due to its potential to accumulate carbohydrate, protein and lipid. However, current microalgae culture technology has been impeded by low biomass production, carbohydrate accumulation and contamination issue. In order to overcome this limitation, this study involves the isolation, screening and identification of acidophilic microalgae from Frog Hill. Then, the effect of different initial pH on growth and carbohydrate productivity was studied toward the selected microalgae. Further cultivation was done in indoor and outdoor using 15L fabricated PBR under optimize pH condition. At the end of experiment, the growth kinetic and carbohydrate productivity for both conditions were evaluated. Total of 4 native acidophilic microalgae were successfully isolated and was identified using 18s RNA. TheScenedesmusparvuswas exhibited highest biomass production and carbohydrate productivity up to 1.2640 ± 0.001 g L−1and 15.47 ± 0.048 mg L−1d−1under highly acidic condition. It also showed a better performance under outdoor cultivation up to 9.54% compared to indoor cultivation. Hence, this research paper showed that the potential of novel acidophilic microalgae survives under extremely condition with high carbohydrate biosynthesis, which could be useful for industrial application.
Carbonic anhydrase (CA) activity by Chlorella sp. in immobilised matrix under carbon dioxide rich cultivation condition.
Authors: Kassim M A , Adnan M F I M , Tan K M , Bakar M H A , Lalung J , Mohamed M S
Published: February 2020

The continuous release of global CO2 and greenhouse gases into the atmophere is considered one of the major contributors for global warming. Currently, microalgal biosequestration using enzyme carbonic anhydrase (CA) has been reported to be one approach that could be applied to overcome the issue. Eventhough this enzyme has been proven to show its potential to convert atmospheric CO2 to bicarbonates, there are remaining issues related to its stability and production parameters that need to be addressed. In this study, the activity of CA produced by immobilized microalgae Chlorella sp. cultivated in a laboratory environment was investigated. For this study, the influence of cultivation conditions such as pH value ranging from 4.00 to 12.00, light intensity ranging from 330 lux to 1000 lux and CO2 concentration ranging from 0.04% to 25% on CA activity were investigated. This present study indicates that the highest CA activity of 1.908 U/min was observed for the cultivation was performed using 15% CO2 with a pH of 8.00 and a light intensity of 550 lux. This suggested that the entrapment of microalgal using a suitable matrix carrier could produce higher CA activity which could be further utilised for extended biomimetic CO2 capture systems.
Potential use of eco-enzyme for the treatment of metal based effluent
Authors: Hemalatha M. , Visantini P.
Published: February 2020

Conversion of wastes into value added products is potentially profitable besides creating a clean environment. Eco-enzyme is one such product produced from fermentation of citrus fruit wastes and the effectiveness of the enzyme in treating metal based effluent was investigated. The characteristics of effluent before and after treatment with eco-enzyme were analysed. There was a great reduction in the level of BOD from 80.0 mg/L to 22.3 mg/L. Eco-enzyme also inhibits the growth of microorganisms in the wastewater. These results confirmed that eco enzyme is capable to treat metal based effluent. Besides, sludge treated with eco-enzyme was studied for its potential use in enhancing the growth of chili and aloe vera. Soil containing eco-enzyme treated sludge promotes better growth in chili. Meanwhile, aloe vera grown on soil containing eco-enzyme treated sludge grown almost equally and healthy in comparison with control. This study provides a solution to prevent sludge dumping to ensure clean environment.
Response surface optimization of the forward extraction of jacalin from jackfruit seeds using AOT/isooctane reverse micellar system
Authors: Mohamad S F S , Said F M , Munaim M S A , Mohamad S , Sulaiman W M A W
Published: February 2020

Jacalin is the major protein contained in the crude extract of jackfruit (Artocarpus heterophyllus) seed that specifically recognizes and binds reversibly to galactose. Conventionally, purification of jacalin is carried out using the tedious and costly chromatographic techniques. In this study, extraction of jacalin from jackfruit seed crude extract were done using the sodium bis(2-ethylhexyl) sulfosuccinate (AOT)-based reverse micellar system. Reverse micellar extraction is an attractive alternative for downstream processing of various proteins. A successful reverse micellar extraction consists of two basic steps: forward and backward extraction. Forward extraction transfers a target protein from an aqueous solution into the reverse micellar solution, while backward extraction releases the protein from the reverse micelles structure into a new aqueous solution. The effects of the aqueous phase pH, NaCl concentration and AOT concentration on the forward extraction efficiency (FEE) are investigated using the response surface methodology (Box-Behnken Design). The main effects and interactions of the parameters are analyzed through the 3D surface plots. The optimum conditions for forward extraction were determined as follows: aqueous phase pH 4.58, 125 mM NaCl and 40 mM AOT. Under the optimal conditions, the FEE reached 88.04±1.30%, closer to 87.99% predicted by the model. The results indicated that AOT/isooctane reverse micelle system is effective in extracting jacalin from the jackfruit seed crude extract and verified the practicability of the BBD model for optimizing the main parameters in the forward extraction of jacalin.
A Study on Physical and Chemical Properties of Detonation Nanodiamond
Authors: Xie Shengzhong , Ma Lingzhi , Zeng Weiping , Gao Peng , Liu Xuezhang
Published: February 2020

Using analysis test methods, such as x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS) and Fourier infrared spectrum (FTIR), x-ray small angle scattering (SAXS), optical correlation spectroscopy (PCS), scanning electron microscopy (SEM) and so on, the researchers systematically studied the detonation nanodiamond (DND)’s physical and chemical properties like crystal structures, surface chemical compositions, surface electrical property and particle size distribution, particle morphology and agglomeration state, etc. The results showed that the crystal structures did not be changed before or after DND disaggregation and dispersion, but the surface chemical compositions, surface electrical property, particle size distribution, particle morphology and agglomeration state all were changed obviously. The systematic data of physical and chemical properties of DND were obtained through the study in this paper, which could provide theoretical basis and technical reference for the application research of DND based on relevant technologies.
Preparation of TiC based Cermet with Different Ratio of Cu and Al
Authors: Wang Nengwei , Wan Shuquan
Published: February 2020

TiC based cermet belongs to superhard tool material, which has high melting point, high hardness and excellent chemical stability. It is the preferred material for cutting tools and wear-resistant components. At the same time, it has excellent conductivity and is also the preferred material for electrode. In this experiment, TiC based cermet was prepared by atmosphere protection sintering method with TiC, Cu and Al as raw materials. The phase analysis was carried out by X-ray diffractometer(XRD), the microstructure was observed by scanning electron microscope (SEM), the element analysis was carried out by energy spectrometer, and the bending strength was tested by universal material tester. The different sintering temperature and the ratio of additive Cu and Al were systematically studied under the premise of controlling the total mass of TiC based cermet, which effect on microstructure and mechanical properties of TiC based cermet. The experimental results show that the bending strength of cermet increases obviously with the increase of copper content in a certain range, and the best mechanical properties of cermet are obtained when the ratio of Cu and Al is 6:4. With the increase of sintering temperature, the mechanical properties of TiC based cermet are significantly strengthened. When the sintering temperature reaches 1100 °C, the grain size is fine and uniform, and the comprehensive properties of the material are the best.
Development of a Stable Carbon Isotopes Analysis Instrument Based on Tunable Diode Laser Absorption Spectroscopy
Authors: Cui Xiaojuan , Zhang Zhirong , Pang Tao , Xia Hua , Sun Pengshuai , Wu Bian , Yu Runqing
Published: February 2020

A compact laser spectrometry instrument was developed for high precision measurements of isotope ratio of CO2 by tunable diode laser absorption spectroscopy in the mid-infrared at 2.7 μm. The experimental spectrum of carbon isotopologues in the gas phase near 3641 cm−1 is very suitable for real-time analysis of these isotopologues. Simultaneous measurements of the mixing ratio and the corresponding δ13C values of CO2 in the atmosphere were performed. The achieved standard deviation (1σ) of δ13C was 1.8‰. The Allan analysis of the time series of the mixing ratio of CO2 shows a measurement precision of 0.2‰ for δ13C with an optimum integration time of about 130 s. The spectrometer is capable of real-time measurements of stable carbon isotope ratios of CO2 under ambient conditions.
A Genetic Algorithm for Economic Order Quantity with a Short Product Life Cycle
Authors: Ouyang Bing Chang
Published: February 2020

Considering a finite time horizon crossing over multiple stages of a product life cycle, this study presents a genetic algorithm to deal with an economic order quantity model with multiple demand rates under a non-periodic policy. In real, the demand of the product life cycle is a non-linear function but we assumes it as four-segment linear or constant approximations in this work. In addition, a multiple-segment to be combined with linear or constant functions can be approximated a nonlinear function. This study does not focus on this, but it provides a genetic algorithm to deal with this proposed inventory problems. The particular of this research is that we develop a proposed replenishment scheme by the differentiating equation of the total cost with respect to replenishment time. Then, calculate the total cost of the proposed scheme as the fitness function to evaluate the populations. In this paper, an explicit procedure to obtain an approximating solution is provided and numerical examples to illustrate the proposed model are shown as well.
Research on Damping Characteristics of Photo-controlled Electrorheological Damper
Authors: Liu Xiang , Chen Yusong , Wang Xinjie
Published: February 2020

Firstly, the expression of PLZT ceramic driving voltage is obtained with external load. Furthermore, the hydrodynamic modelling of the electrorheological fluid in the circular damping channel is carried out, and the relationship between the pressure difference between the two ends of the damping channel and the PLZT ceramic driving voltage is derived, and the hydrodynamic simulation of the electrorheological fluid in the circular damping channel was carried out in the fluid simulation software Fluent. The simulation result shows the correctness of the mathematic model and the feasibility of photo-controlled electrorheological damper.
The Study of Microstructure and Mechanical Properties of Two High Strength Steels
Authors: Li Shihan , Wang Xiaolin , Zhao Wei , Li Zunzhao
Published: February 2020

The microstructure and mechanical properties of two high strength steels with different carbon content were studied by means of metallographic microscope, scanning electron microscope, transmission electron microscope and mechanical testing machine. The results showed that the microstructure of the 0.2C (wt.%) steel and 0.4C (wt.%) steel was tempered sorbite, a large number of granular carbides dispersed on the ferritic matrix. The carbides contained Fe3C and M6C (Fe3Mo3C) phase. Compared with 0.2C steel, the content of the carbides of 0.4C steel was larger, while the particle size was smaller. The tensile and yield strength of 0.4C steel were higher, but the elongation was lower and the toughness was worse. In addition, the hardness values of the two materials were basically the same.
Friction and Wear Mechanism of High Temperature Brake Friction Materials
Authors: Han Junjiao , Qiu Qian , Ning Keyan , Han Ming , Zhang Nan , Lang Chaoyang , Liu Zhe , Ji Zhen , Jia Chengchang
Published: February 2020

In this paper, the microstructure and frictional wear mechanism of iron based high temperature brake friction materials prepared by powder metallurgy are studied. The results show that iron based friction materials are mainly composed of iron matrix, graphite and hard phase. Under the working condition of rotating speed of 6000r/min, the frictional wear mechanism is mainly abrasive wear and slight oxidative wear. Under the working condition of rotating speed of 8800r/min, the frictional wear mechanism is mainly abrasive wear, adhesive wear and oxidative wear.
Research on Cumulative Damage Evaluation Method for Structural Impact on Airborne Armored Vehicle in Landing Process
Authors: Fu Xinhua , Lu Yong , Wang Jun , Chen Xueyang
Published: February 2020

Since it was very costly and complicated to analyze cumulative damage caused by structural impact on airborne armored vehicle in landing process using real equipment airdrop test, finite element method(FEM) was taken to build a finite element(FE) model of airborne armored vehicle and airbag system to simulate the landing impact process of airborne armored vehicle. In combination with Lemaitre Damage Model and the damage evolution law of materials, the cumulative damage caused by structural impact of vehicle was calculated. The cumulative damage of structure of airborne armored vehicle in multiple landing processes was assessed, results of which were expected to provide theoretical guidance for the operational use and maintenance of airborne armored vehicle.
Numerical Simulation of a Bionic Blade on Small-Scale Wind Turbine
Authors: Kung Kuang-Yuan , Chen Jun-Liang , Hsu Cheng-Hsing , Tsai Wei-Feng
Published: February 2020

This study presents the aerodynamic characteristics of a small-scale horizontal axis wind turbine (HAWT) with bionic blade contours. Taiwan incense cedar was chosen as imitations. On account of the contour of the winged disseminules and the ANSYS FLUENT 14, we designed the bionic blades to process the computations of aerodynamic characteristics of the bionic wind turbine blades. The aerodynamic characteristics and the wind/electricity power transform efficiency of the turbines were examined in a wind tunnel. The wind tunnel experimental outcomes showed that the wind/electricity transformation efficiency of the wind turbine setup could reach to 37%, and it is benefit environment and global energy management.
Research on Static Characteristics of Steel-Concrete Composite Beam Cable-Stayed Bridge during Construction
Authors: Yang Zeying , Qu Yongye , Qu Jianbo , Zhang Yalei , Qi Wenchao , Xie Xinnan
Published: February 2020

As the construction continues, the structural system and load of the cable-stayed bridge will change. At different construction stages, the forces and deformations of the structure will have their own characteristics. In this paper, in order to study the static characteristics of steel-concrete composite beam cable-stayed bridge during construction, the Jiqi Yellow River Highway Bridge is used as the engineering background, and the finite element modeling is carried out by midas. The main beam, cable tower and stay cable of the cable-stayed bridge are analyzed respectively. Among them, the static characteristics of steel and concrete bridge deck during construction are specially analyzed. In this way, it is ensured that all structures are in a safe state during the construction process, and then the construction.
Two-rotation Orthogonal Combination Design Optimizes the Process Parameters of Fresh-cut Rosa Green
Authors: Han Peixin , Feng Xiaoguang , Zhao Xin , Liu Huijun , Chen Xiangning
Published: February 2020

In order to improve product quality, extend the shelf life of fresh-cut Rosa green, and reduce the loss rate of processing and circulation, the secondary rotation-orthogonal composite design is used to optimize the process parameters of ready-to-eat fresh-cut Rosa green. The results showed that weight loss rate, conductivity, POD, Vc, total number of colonies, nitrite, and chromaticity value a were significantly correlated with storage time (p<0.01). Principal component analysis showed that the two principal components accounted for 96.215% of the contribution rate. Fresh cut Rosa green quality evaluation value comprehensive value Y = -0.371 Chromaticity value a - 0.373 Weight loss rate -0.357 Total number of colonies -0.005 POD + 0.374 Vc - 0.333 Relative conductivity - 0.269 Nitrite. The secondary disinfection sodium hypochlorite concentration, the ratio of O2 (v / v) and CO2 (v / v) and the storage temperature were studied to influence the comprehensive quality of fresh cut Rosa green during storage. The results showed that the optimal process parameters were: secondary disinfection sodium hypochlorite concentration was 31.43ppm, O2 concentration was 3.04%, CO2 concentration was 5.55%, and storage temperature was 3.68°C. Fresh cut Rosa green processed under the optimum process parameters can be stored for 15 days. This study has positive significance for the post-harvest processing of fresh cut Rosa green.