bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and Analysis of AC14 Ship Anchor
Authors: Kandregula Ramu , Hemanth B , Harikishan A
Published: November 2021

A Ship’s anchor makes a ship to be at a fixed location against currents and winds when ship is in rest position. Purpose of anchor is to restrict the drifting of ship, which is occurs due to the currents. Even though there are many different types of anchor, present paper intended to do design and analysis on stockless anchor AC14 type. Project aims to determine the equivalent von-mises stress and maximum deformation in anchor when subjected to proof test. Proof test load is decided based on the mass of the anchor. (Reference is taken for the relationship of proof test load and mass of the anchor. Solid modeling of Stockless ship anchor model is carried out on NX 11.0 and modal analysis of ship anchor is carried out using ANSYS 16.0
Effect of the parameters in electromagnetic field assisted electric discharge machining
Authors: Raut S V , Bongale A , Kumar S
Published: November 2021

The electric discharge machining is a non-conventional machining process, in which the spark is electric spark is generate in gap between the work piece and electrode. Due to heat generated by spark in between the workpiece and electrode, the material get vaporized from small area form workpiece and get cool down with the help of dielectric fluid. In present study low carbon mold steel use as a work piece and copper electrode is used. The electromagnetic field included in the process to analyze the effect of the input parameters on the machine response parameters like MRR and the surface roughness value (Ra). The study is done on EDM process with and without EMF by varying the input parameters Ton (μs) and keeping the other parameters constant (Toff (μs), Current (A) & Voltage (V)). The set of the neodymium magnets are used in the set up having 4500 gauss units. The circular plate is designed to hold the neodymium magnets nearer to the work piece using CATIA V5 version. 3D printer is used to fabricate the circular plate that holds the electromagnets precisely near to the area under spark to have a maximum effect of EMF in the EDM process. The experimentations shows that response parameter shows good output at pulse on time of 200 ms and 300 ms with and without EMF respectively.
A Review on Lightweight Metal Component Forming and its Application
Authors: Madhusudhana H K , Gaitonde V N , Satish Jangali G
Published: November 2021

The present research focused on reviewing forming technology and inspired various method forming processes for different lightweight materials. Nowadays, to improve modern automobiles’ fuel economy while preserving safety and efficiency, advanced materials are essential. Since accelerating a lighter object requires less energy than a heavier one, lightweight materials offer great potential to improve vehicle performance. Innovative forming technologies are discussed concerning each approach and their contribution to lightweight material application. New metal forming methods are implemented to fulfill lightweight material applications in various fields.
Amplitude modulator of Multi-walled Carbon nanotubes/Chitin in the C-band region
Authors: Muhamad Apandi N H , Ahmad H , Ibrahim M H , Ahmad F
Published: November 2021

In ultrafast all-optical signal processing, the all-optical method is crucial, and all-fiber technique offers a wide range of applications in optical communications. This study investigated the amplitude modulation using multi-walled carbon nanotubes (MWCNTs) embedded into chitin as saturable absorber (SA). The MWCNTs-chitin SA is fabricate using a liquid phase exfoliation method to reduce complexity and produce an excellent material quality. In this paper, an optical amplitude modulator produced a linear region with a regression line of the peak intensity at pump power range from 17.92 mW to 67.92 mW with modulation efficiency of 0.50 dB/mW.
Generation of stable penta-wavelength ytterbium doped fiber laser by spatial-mode beating in 1-µm waveband
Authors: Mat Salim M A , Ismail M A , Azzuhri Saaidal R , Razak M Z A , Bakhtiar H , Bidin N.
Published: November 2021

Penta-wavelength ytterbium doped-fiber laser had been successfully generated by usingspatial mode beating method at room temperature. A G652D premium fiber patch cable was inserted inside the polarization controller (PC) and connected to an ytterbium-doped fiber ring cavity. By increasing the pump power, stable multi-wavelength with side-mode suppression ratio (SMSR) from 25 dB to 40 dB were obtained from dual-wavelength and up to penta-wavelengths respectively. The uniform wavelength interval spacing was 0.67 nm whereas peak power fluctuation and wavelength shifts were 0.6 dBm and 0.01 nm, respectively for all sets of multi-wavelength. These simple, easy and reliable system offer a stable multi-wavelength generation in a 1-micrometer waveband.
Generation of stable mode-locked fiber laser based MWCNTs in 1.5-µm waveband
Authors: Mat Salim M A , Ismail M A , Razak M Z A , Azzuhri Saaidal R. , Bakhtiar H , Bidin N
Published: November 2021

Pulses fiber laser had been successfully generated by using multi-wall carbon nanotubes thin film saturable absorber at room temperature. The saturable absorber is incorporated into a ring laser cavity. A stable Kelly sidebands mode-locked pulse spectrum with 1561.3 nm wavelength at the pump power of 86.8 mW. The repetition rate and pulse width of 12.3 MHz and 0.51 picosecond, respectively. A stable operation is observed for an hour at room temperature. These simple and reliable system features offer interesting research study especially in mode-locked pulse generation at 1.5 μm waveband.
Overview of surface plasmon resonance optical sensors for Covid-19 (SARS-CoV-2) detection
Authors: Zain H A , Batumalay M , Harun S W
Published: November 2021

The SARS-CoV-2 i.e., the novel severe acute respiratory syndrome corona virus; has caused massive loss of life. Mitigating this pandemic requires rapid inexpensive technologies for testing COVID-19. Optical sensors can be used to detect the Covid-19 virus by the surface Plasmon resonance phenomenon. Surface plasmon resonance sensors have good sensitivity, response times, fine resolution, and limits of detection. This paper, provides a brief overview on the COVID-19 effects, currently used testing technology, and potential of surface plasmon resonance optical sensors use for detecting this virus.
The generation of nanosecond pulses at C-band region with titanium dioxide as a saturable absorber
Authors: Ahmed N , Omar S , Zulkipli NF , Jusoh Z , Rahman HA , Musa B , Harun SW
Published: November 2021

A passive mode-locked in an erbium-doped fiber laser with titanium dioxide (TiO2) film as a saturable absorber (SA) has been successfully demonstrated. The film is fabricated using a liquid phase exfoliation, which offers a simple and low-cost method. The self-starting mode-locked was created by inserting a 200-meter-long single-mode fiber into the laser cavity to balance the nonlinearity and dispersion of the cavity. The pulses operate stably at a central wavelength of 1560 nm. The pulse repetition rate was almost fixed at 988 kHz at a tuneable pump power from 145.83 mW to 187.04 mW. The repetition rate shows excellent stability with a signal-to-noise ratio (SNR) of 69 dB whilst the pulse width was virtually constant at 230 ns. The maximum output power was measured at 2.17 mW, eliciting maximum pulse energy of 2.19 nJ. This experiment demonstrates that stable mode-locked pulsed can be generated using TiO2-SA.
Hafnium Bismuth Erbium Co-Doped Fiber Based Dark Pulses Generation With Black Phosphorus As Saturable Absorber
Authors: Ahmad A , Rahman M F A , Johari M A M , Latiff A A , Jali M H , Yusof H H M , Cheng X S , Muhammad A R , Harun S W
Published: November 2021

A dark pulse generation is demonstrated in a fiber laser configured with a 20 cm long HBEDF and multilayer Black Phosphorus as a gain medium and saturable absorber, respectively. Dark pulses fiber laser at 1.5 µm region was obtained when the pump power exceeds the threshold of 147 mW. Meanwhile, the spectrum of the dark pulse is centred at 1556.40 nm, with the 3 dB bandwidth of 0.12 nm and the separation between adjacent pulses is 1145 ns, corresponding to the cavity length of 211 m. The pulse width was measured to be around 320 ns. The radio-frequency spectrum of the dark pulse, which was measured within the 20 MHz range. More than 17 harmonics were observed within this range, which indicates the mode-locking operation of the laser. The fundamental frequency was obtained at 1.1 MHz, which agreed with the oscilloscope trace. Furthermore, it shows a signal to noise ratio of about 36.58 dB, which indicates good stability. The maximum output power of 0.78 mW and pulse energy of 0.78 nJ were obtained at 187 mW pump power.
Whispering gallery mode resonance excitations on a partially gold coated bottle microresonator
Authors: Mohd Nasir Mohd Narizee , Murugan G S , Zervas M N
Published: November 2021

The study on the excitations of whispering gallery mode (WGM) resonances optical bottle microresonator (BMR) partially coated with a thin gold Au metal film is presented. The BMR was fabricated through “soften-and-compress” technique on a small section of standard optical fibre. Depositing Au particles on the spheroidal curvature of the BMR surface yields a thin metal-film of a meniscus profile with 200 nm maximum gold thickness and tapered edges. A polarization resolved experimental setup was used to excite TE- and TM-mode resonances. Coupling strengths of the excited WGMs would vary with different coupling arrangements relative to the position of the meniscus Au film. Calculated Q-factor values of composite TE and TM mode resonances were determined to be in the range 1800 and 2700, respectively.
Research on High-power Transmission Technology of Satellite Borne RF Connector
Authors: Li Xiang , Peng Qinghua , Xie Qian , Zhao Min , Cai Libing , Tong Lijun
Published: November 2021

The reliability of the communication link shall be affected severely due to failure modes such as multipactor, low pressure discharge, and thermal damage that are commonly found in the RF connector when it performs high-power microwave signal transmission in the vacuum environment of outer space. This paper proposes supporting measures in respect of design against multipactor, low pressure discharge and thermal damage after analyzing mechanisms of failure modes of the RF connectors when it transmits high-power microwave signals in a vacuum environment. Upon tests, these proposed measures can effectively guarantee the reliability of the RF coaxial connector transmitting high-power signals in vacuum.
Design of QAM-OFDM Radar-Communication Integrated Signal Based on Golay Complementary sequences
Authors: Ye Ming Kun , Zhu Qin , Dai Peng Cheng , Tang Jun
Published: November 2021

The integration of radar and communication is conducive to improving the utilization rate of hardware resources and spectrum. To address the issue that the communication information in orthogonal frequency division multiplexing (OFDM) integrated signal for radar and communication affects detection performance, an OFDM integrated signal for radar and communication based on precoding was proposed. The communication information of the integrated signal was pre-coded by using the Gray Complementary Sequences (GCS) with better correlation performance to improve the performance of the ambiguity function of the integrated signal and its detection ability. Simulation results show that GCS have better correlation performance compared to M and Gold sequences, and the OFDM integrated signal pre-coded by GCS has lower Peak Sidelobes Ratio (PSLR) and comparable radar performance to LFM.
Research and application of bolt defects detection technology based on machine learning
Authors: Yao Zhidong , Lu Jiaqi , Liu Yesen , Wang Gang
Published: November 2021

With the development of computer technology, the technology based on computer machine learning plays an important role in various fields. Using drones for collecting image data and using machine learning to analyze the collected image data have become the current general method of intelligent detection technology. As the main machine learning method, deep learning is commonly used in image analysis, but it requires many high-quality training samples and high-performance embedded system. In the engineering quality and safety detection with few training samples, the detection effect of this method is not satisfactory. To solve this problem, computer vision and machine learning technology are introduced into image analysis of bolt, based on the analysis and mining of historical image samples, the recognition and judgment of new collected images can be realized by matching the newly collected image samples and historical samples. Taking the bolt on a steel structure bridge as an example, this method is used to recognize the bolt appearance image collected by UAV. The results show that the method can effectively identify the appearance state of bolts, with fast calculation speed and high recognition accuracy.
Research on Command Generation Strategy of Roll and pitch seeker
Authors: Lin Fan , Shen Xinjie
Published: November 2021

The roll pitch seeker has a large field of view, which can achieve large off-axis angle attacks. At the same time, it has a simple structure and is easy to miniaturize, which is beneficial to the overall design of the missile. However, the over-tracking problem of the rolling seeker restricts her application in engineering. To solve this problem, this paper proposes a method to calculate the roll frame angle by using the angular rate of the projectile line of sight when the pitch frame angle is small. The simulation results show that this method is effective in the overhead tracking control.
Study on the anodic oxidation performance of a rolled AA5252 aluminum alloy sheet with different thicknesses
Authors: Wu Jianxin , Ye Qilua , Yang Bin , Gao Chong
Published: November 2021

Microstructures of AA5252 aluminum alloy sheets from surface to the center were observed by use of scanning electron microscope with electron backscatter detector assembly, and treated by anodic oxidation. Results showed that changes of the grain structures and textures of the AA5252 alloy sheets occur from the surface to the center layers. The anodic oxidation surface quality of the AA5252 aluminum alloy is closely related to the area ratio and distribution uniformity of Cube texture.
Effect of Hindered Amine Light Stabilizer on Properties of HDPE/Kaolin Composites for Hydraulic Gate and its Mechanism Analysis
Authors: Song Li , Liu Huaqiang , Yang Bin , Cai Yiping
Published: November 2021

High density polyethylene (HDPE)/kaolin composites with different hindered Amine light stabilizers were prepared by blending granulation. The mechanical properties and dynamic thermodynamic changes before and after aging were discussed and studied. The precipitates were analyzed by FI-IR and H1-NMR, and the precipitation reason and anti-aging difference of different light stabilizers were discussed and compared. The results showed that the mechanical properties retention rates of light stabilizer 2020, light stabilizer 944, light stabilizer 123, light stabi-lizer 770 and light stabilizer 292 were 87.1%, 81.7% and 79.1%, respectively %Light stabilizer 2020 and light stabilizer 944 with large molecular weight are more easily compatible with the system, not easy to precipitate, and have a better an-ti-aging effect. At the same time, light stabilizer 2020 with dense hindered amine structure has excellent anti-aging effect. This study provides a reference for the selection of light stabilizer and failure analysis of light aging resistance of HDPE system.
Parametric Analysis on Three-Points Bending Test of Typical Skin-Stringer Structure
Authors: Wang Zhe , Chen Xiangming , Zou Peng , Li Xinxiang , Liang Qingxianglong , Yang Junchao
Published: November 2021

Stringer-skin debonding was one of the most important failure models in stiffened composite panels. In this paper, three-points bending tests were performed on representative stringer-skin structure of composite wing to simulate the flange-skin interface behavior and to obtain the failure mode and failure load. A 3D finite element model was built by using ABAQUS software to simulate interface failure with cohesive zone model. The numerical results agree well with test data, which validate the rationality of the finite element model. Hence the influence of factors during manufacture, installation and test in three-points bending tests, such as off-axis displacement, inclination loading and span, is studied. Results show that the initial debonding load and failure load of specimen decrease as the displacement from loading axis to central axis increases. The load of specimen decreases as the span increases. The influence of inclination loading is insignificant when the inclination angle is less than 6 degree. However, the initial debonding load and failure load of specimen decreases in varying degrees as the inclination loads increases. Furthermore, the initial debonding load decreases rapidly.
Development of Pictorial Card “Kencana” (Disaster Preparation) as a Media of Group Guidance Services in SMP N 1 Wonosari
Authors: Purnama Diana Septi , Oktaviana Naafi’ Fajar
Published: November 2021

This study is aimed to develop a product called the Kartu Kesiapsiagaan Bencana “KENCANA” (Disaster Preparedness) pictorial card which can be used as a media for group guidance services in junior high schools. The material theme of this card is physical, psychological, social, and spiritual disaster preparedness. This research is an R&D (Research and Development) research by adopting the Borg and Gall development model. The stages of this research consisted of: 1) the data collection stage, 2) the product planning stage, 3) the product development stage and 4) the validation and testing stages. The research subjects were 8th grade students of SMP N 1 Wonosari, Gunungkidul. The results showed that the pictorial cards KENCANA (Disaster Preparedness) were suitable for being used by the counseling teacher as a media for group guidance services and also used as a media for evaluating student understanding of the preparedness material that had been previously presented with good criteria based on all aspects that have been validated and tested.
Spatial Evapotranspiration Modeling Assisted With Landsat 8 Image Using Sebal And Geographically Weighted Regression Methods In Magelang District
Authors: Nugraha AF , Hadi BS
Published: November 2021

Information about evapotranspiration is very important in relation to vegetation because it can be used for planning both in urban planning and agriculture. Magelang Regency has a lot of vegetated green land, both agricultural and non-agricultural and has no information about evapotranspiration. The calculation of evapotranspiration uses the SEBAL (Surface Energy Balance Algorithm for Land) method and modeling uses the GWR (Geographiccaly Weighted Regression) model. Calculation and modeling assisted by QGIS 2.14, QGIS 3.6, SPSS 20, and GWR 4.09 applications. The results showed that (1) GWR evapotranspiration model with significance (sig.) 5% is divided into 3 sub-district groups according to the significant variables in the sub-district (2) NDVI and Surface Albedo variables have a small effect on a global scale and have a large effect on a local scale.
Commercial Multirotor UAV Campaign on Data Acquisition for Disaster Management
Authors: Putro S T , Nucifera F , Febriarta E
Published: November 2021

UAV usage and interest have shown great popularity recently, especially for commercial multirotor. It is cheap, easy to use, flexible, and has many capabilities. That is why multirotor is widely chosen in disaster management. As a technology, it possesses certain aspects. Review of how the implementation of multirotor UAV in disaster management is important to gain improvement in the technology and evaluate at how we use it. This paper provides insight into commercial multirotor UAV campaign in disaster management through literature study and personal experience in a related theme. Similar ideas on the development of UAV and its application in disaster management then combine with personal experience was used to identify the advantage, disadvantages, challenges, and opportunities of multirotor drone applications. The result suggested that multirotor UAV has limited capability in conducting disaster management campaigns. The weakness in deploying multirotor is related to the lack of technology which may be overcome in the future as the development in hardware and software technology.
Settlement Suitability Analysis Based on the Catastrophic Eruption of Sinabung
Authors: Utami W , Rahmat A , Sialagan BH , Exaudia S , Turnip AL
Published: November 2021

Mount Sinabung is an active volcano after being 'dormant' for a long time since the 1600s. Sinabung has begun to show its activities from 2010 to 2020, so that it has a long impact on community activities, damage to settlements, agricultural and threats to the lives of residents around Sinabung. This study aims to determine the conditions of land use in disaster-prone areas in relation to spatial patterns and levels of disaster prone. The research method is carried out through spatial analysis by overlaying the land use map with the spatial planning map to produce a land use suitability map. The spatial pattern suitability map is overlaid with a disaster hazard map to determine the level of security in settlements. The results showed that 5 affected Districts, namely in the Districts of Naman Teran, Payung, Simpang Empat, Tiganderket, Munte, the safe zone was 145.66 hectares, the less safe zone was 0.98 hectares, the unsafe zone was 36.91 hectares and the very insecure zone was 1.25 hectares. It is hoped that the spatial analysis regarding the distribution of safe locations for settlements is expected to become a policy material for the government to formulate arrangements for the use and utilization of space so that the spatial planning policies that are established are in line with efforts to reduce the risk of the eruption of Mount Sinabung disaster.
Antifungal activity of crude extracts of Ageratum conyzoides and Chromolaena odorata for management of Lasiodiplodia theobromae and Lasiodiplodia pseudotheobromae through in vitro evaluation
Authors: Asman Asman , Adelvia  , Rosmana Ade , Sjam Sylvia , Hamdayanty  , Fakhruddin Andi , Natsir Nuni Ujiani
Published: November 2021

Lasiodiplodia is an important genus of fungi causing destructive diseases on perennial crops, including cocoa. Two crucial species of Lasiodiplodia that cause diseases in cocoa are Lasiodiplodia theobromae and Lasiodiplodia pseutheobromae. A variety of weeds is the potential to be applied as botanical fungicides to control the pathogens. The main objective of this study was to evaluate Ageratum conyzoides and Chromolaena odorata leaf extract to inhibit the growth of L. theobromae and L. pseudotheobromae on a synthetic medium. Solvent organic was methanol for weed extraction with a ratio of 1:5. The experiment was conducted through the poison food technique method, both in the solid and liquid medium in three different concentrations, 1, 3, and 5%. The result showed that A. conyzoides and C. odorata were significantly inhibited the colony growth of both Lasiodiplodia in all concentrations in a solid medium. A. conyzoides performed better than C. odorata in all concentrations of both Lasiodiplodia in inhibition. A. conyzoides 5% performed well to suppress the colony growth of L. pseudotheobromae (100%), followed by A. conyzoides 3% and A. conyzoides 1%. A. conyzoides 5% able to inhibit the colony growth of L. theobromae until 100%, followed by A. conyzoides 3% and 1%. Meanwhile, A. conyzoides and C. odorata extract tested on PDB medium at 1, 3, and 5% reduced the fungal biomass significantly at all concentrations. C. odorata was found most effective in inhibiting fungal biomass of both pathogens either on wet weight or on dry weight at 1, 3, and 5% %. A. conyzoides and C. odorata can manage the growth of L. theobromae and L. pseudotheobromae through in vitro conditions.
Identification of the potential and palm sap characteristics for palm sugar business development in Lombo Village, Sidrap Regency
Authors: Syahidah  , Makkarennu  , Caroline A , Rizaldy A A , Syahid M , Fitriwati  , Syahwiah A
Published: November 2021

Sugar palm is a commodity that has a high value of benefits and has become one of the home industries that are mostly cultivated by rural communities in Indonesia. Likewise, the community in Lombo Village, Pituriase sub-district, Sidrap district also cultivates palm sugar as a source of income in addition to their main job as a farmer. The purpose of this study were to identify the potential and characteristics of sugar palm and palm sap to serve as the basis for developing the palm sugar business in Lombo Village. This research was conducted using a sampling method to identify the potential of palm trees and interview methods to identify production data and characteristics of palm sap. The results showed that the number of sugar palm trees in Lombo Village was 2,038 trees consisting of 118 trees being tapped, 585 trees ready to be tapped, and 1,335 trees still waiting for about 3-4 years to be tapped. The average sap production is 995 liters/day and produces 139.2 kg/day of sugar, so it can be seen that the content of brix of palm sap in Lombo Village is 14%. The selling price of sugar produced by the community is Rp. 25,000- per kg so that the sales received by the craftsmen in Lombo Village is Rp. 3,480,000 - per day or Rp. 108,750,-/craftsman/day.
Morphological diversity and relationship among cashew (Anacardium occidentale L) individuals in three districts of Southeast Sulawesi, Indonesia
Authors: Boer D. , Ladati N. , Jumarno  , Irwan  , Arsyad M A , Larekeng S H
Published: November 2021

Cashew (Anacardium occidentale L), a species belonging to the family Anacardiaceae, has been cultivated throughout most of Indonesia’s areas and has become a priority commodity in Southeast Sulawesi for years. However, the information about its variation on morphology and relationship among individuals are still limited. This study aimed to determine the morphological variations and relationships among cashew individuals in three districts (Konawe, South Konawe, and East Kolaka) of Southeast Sulawesi. As many as ninety individuals were analyzed on 15 morphological variables for the variations and 47 variables using the complete linkage method based on Gower distance for the clustering. The coefficients of variation were varied on all evaluated variables. The highest was the height of main branches (cm), ranging from 47.32 % to 73.72 %. Meanwhile, nut length had the lowest coefficient of variation (6.75%-7.99%). The individuals were divided into two main clusters with two sub-clusters for each cluster.
Physicochemical and color characteristic of the Bawakaraeng Forest Honey, South Sulawesi
Authors: Syahriati  , UA Nur Fitriani , Latifah Husnah , Nirwana
Published: November 2021

Honey is a thick liquid produced by bees consisting of natural sugars derived from flower nectar or plant secretions. The content of monosaccharides and fructose causes the sweetness of honey, and glucose compounds are naturally found in honey derived from the juices of food carried by bees. This study aims to determine physicochemical and color characteristics of forest honey from Bawakaraeng Mountain with the quality of honey obtained in accordance with the Indonesian National Standard. Characterization of the physicochemical quality of total sugar content was measured using a refractometer, acidity by pH meter, and color characteristics by Hunter Methods using chromameter instruments. In the results, color characterization of forest honey L* 22.28-22.46; a* 3.30-3.37; b* 4.74-4.87, L value indicates a lightness level that tends to be dark and a yellow-red chromatic color range (YR). Then water content is 21.06%, total sugar content is 49.53%, and pH 4. Finally, physicochemical and color characteristics analysis of forest honey needs to be studied more rapidly on the content of bioactive compounds and their benefits for health. The potential of forest honey from the Sinjai Regency is a new functional food that provides high antioxidant content value and rich nutrients.
Health assessment of vegetation composition in the reclamation area of PT Natarang Mining, Tanggamus Regency, Lampung Province
Authors: Safe’i Rahmat , Arwanda Elmo Rialdy , Doria Cici , Taskirawati Ira
Published: November 2021

Reclamation is a recovery activity in mining areas, one of which is revegetation. The success of revegetation plants can be seen from the health of the composition and structure of the vegetation when the trees are six years old and over. This study aims to determine the health of the vegetation composition (location, type, and level of tree damage) in the reclamation area of PT Natarang Mining, Tanggamus Regency, Lampung Province. The location of this research is in the area around the main office of PT Natarang Mining, Way Linggo Forest, Bandar Negeri Semuong, Tanggamus Regency, covering an area of 2.97 Ha. The research was conducted through vegetation analysis using the circular plot method and assessing the health of the vegetation composition based on the damage index at the plot level. The results showed that tree vegetation obtained 12 species. The most common tree species found wasFalcataria moluccana(Sengon) which amounted to 22 individuals. The most significant contribution of tree species indicated by the highest importance value index wasFalcataria moluccana. The location of most damage found in most of the plots was at the bottom of the stem (code 3) and the bottom and top of the stem (code 4). Types of open wound damage (code 03) and gall rust (code 26) were the most dominant causes of damage, with an average damage rate of 35% and 22%, respectively. The health value of the vegetation composition has a value range of 1.20 – 2.00. The average health value of the vegetation composition is 1.50, which is included in the medium category.
Prediction of erosion and sedimentation rates using SWAT (soil and water assessment tool) method in Malino Sub Watershed Jeneberang Watershed
Authors: Soma Andang Suryana , Wahyuni  , Musdalifah
Published: November 2021

The increase in population will encourage the community to transfer the function of agricultural land in the Malino sub-watershed. Land use dramatically affects the level of erosion and sedimentation. The use of SWAT models can identify, assess, and evaluate the extent of a watershed’s problems. This study aims to determine the spatial distribution of HRU and analyze the rate of erosion and sedimentation in the Malino sub-watershed. The results showed that the most HRU is found in secondary dryland forests, as much as 624 HRU (32.21%). The level of erosion rate of the category is very light with an erosion value of 5.21 tons/ha/year, light 31.19 tons/ha/year, moderate 104.91 tons/ha/year, weight 267.10 tons/ha/year, and hefty 616.74 tons/ha/year. The most significant sedimentation rate was found in sub-watershed 18 of 71.97 tons/ha/year and subwatershed 10 of 13.31 tons/ha/year.
A mixture of red kidney beans (Phaseolus vulgaris L.) and bee bread of honey bees (Wallacetrigona incise) as artificial feed for silkworm (Bombyx mori L.)
Authors: Nuraeni Sitti , Latif Nurfadilah , Prastiyo Andi , Nurfausiah  , Armidha Nirmala
Published: November 2021

The supply of silk thread in Indonesia is only able to meet 5% of the national demand, and 95% must import it. Success in silk thread production comes from natural silk cultivation activities, namely mulberry cultivation. Meanwhile, the productivity of mulberry leaves in Indonesia is very low. This study aims to determine the feeding ability, growth of silkworm resistance, the effect of cocoon productivity pro4duced by silkworms when fed artificial feed. This research was conducted at the Forest Protection and Entomology Laboratory, Hasanuddin University. Artificial feed formulation in the form of a mixture of red kidney beans and bee bread with the comparison of mulberry leaves, red kidney beans, and bee bread were P1 (33:24:25), P2 (45:24:15); P3 (mulberry leaves and red kidney beans 40:44), P4 (mulberry leaves and bee bread 40:44), and P5 (natural feed of fresh mulberry leaves as control). Treatments P1, P2, P3, and P4 were added agar, vitamin C, sugar, and 100 ml of distilled water. The results of this study indicate that the percentage of artificial feed can be consumed 3 g/larva/day. Parameters of 5th instar larval survival, growth index, and cocoon quality in all feed compositions showed no significant differences.
The effect of competence and entrepreneurial capability of farmers on the growth of Bali Cattle farming business
Authors: Saleh M I , Tanri G R , Siregar A R , Amrullah  , Hatta M , Darwis M , Astaman P
Published: November 2021

One of the emphasis on the performance of the Bali cattle business is to improve the competence and entrepreneurial skills of farmers, which until now are still considered low. The purpose of this study was to determine the effect of the competence and entrepreneurial ability of farmers on the growth of Bali cattle farming in Tanete Riaja District, Barru Regency, South Sulawesi Province. This type of research is explanatory research. Research based on livestock farmer groups with a population of Bali cattle farmers as many as 140 farmers. Determination of the number of samples using the Slovin formula and stratified random sampling method as many as 58 people with details of the Livestock Farmer Group Lempangeng 12 people, Makkawaru 22 people, Sipurennue 12 people and Lempang 12 people. Collecting data through interviews with the help of questionnaires measured using a Likert scale, that is a score of 1 to 3 with category 1 = not good; 2 = moderate; and 3 = good. The data collected were analyzed using multiple linear regression. The results showed that the competence of farmers and the entrepreneurial ability of farmers had a significant effect on the growth of the Bali cattle business.
Cyanobacteria in freshwater Lake Dikoye (Pribaikalsky district, Buryatia, Siberia) under intensive eutrophication
Authors: Tsyrenova D D , Zaitseva S V , Dagurova O P , Dambaev V B , Barkhutova D D
Published: November 2021

We studied freshwater Lake Dikoye located in the coastal zone of Lake Baikal. Negative changes associated with cyanobacterial bloom were observed in the lake. Phototrophs were represented by cyanobacteria, green algae, and diatoms. In the microbial community, Cyanobacteria were the dominant phylum and accounted for up to 48% of the total diversity. Cyanobacteria were represented by 7 genera and 9 species. Microcystis aeruginosa, a potentially toxic species, was dominant among cyanobacteria. According to chlorophyll a content, the lake should be assigned to eutrophic ones. The bacterial eutrophication index for the lake studied varied from 1.17 (middle eutrophic) to 28.2 (hypereutrophic) during cyanobacterial bloom.
The composition of haypiles of Turuchan pika (Preliminary analysis)
Authors: Lenkhoboeva S Y , Chepinoga V V , Borisova N G , Chimitov D G , Belova V A , Skornyakova A M , Nikulin A A , Nikulina N A , Ilchenko O G
Published: November 2021

The species composition and abundance of plants in the Turuchan pika habitat and in its haypiles were studied in the talus surrounded by taiga on the Primorsky ridge. With the Ivlev’s Electivity Index, it was found that the pika was selective in collecting food: Veratrum nigrum and Urtica dioica, being relatively rare in the habitat, were highly preferred and abundant in the haypiles. The bulk of the haypiles also consisted of 4 species (Rubus matsumuranus, Sambucus sibirica, Populus tremula, Spiraea media) with a high abundance in the habitat and collected proportionally with their abundance. Many plant species being abundant in the habitat were not stored by pikas.
Biogenic elements and organic matter production in the ecosystem of Lake Arey, Transbaikal region, Russia
Authors: Tsybekmitova G Ts , Morozova M O
Published: November 2021

Maintaining an ecological balance of Lake Arey is crucial in terms of nature conservation. Lake Arey is located in Eastern Siberia and is a central object of a designated conservation area of regional significance. The lake is used for recreation (organized and unorganized tourism, sport fishing, mud collection for balneological purposes) not only by residents but also by holidaymakers from other regions. In terms of mineralization level, Lake Arey is a freshwater body. Significant factors affecting the aquatic ecosystem are temperature, TDS, pH and dissolved oxygen, depth, and turbidity. High contents of ammonium ions are observed in the ecosystem. The concentration of dissolved inorganic phosphorus is 23.6% of total phosphorus. The ratio of PO (permanganate oxidizing ability of organic matter) to COD (chemical oxygen demand) indicates active processes of production, mineralization, and transformation of organic matter in the water body. Carotenoids prevail in planktonic pigments. The chlorophyll a amount is insignificant. The chlorophyll b content increases from July to September. Currently, Lake Arey belongs to the α-mesotrophic type of water body. However, increased anthropogenic load and high-water years can promote eutrophication processes.
Controllable assembly of skeletal muscle-like bundles through 3D bioprinting
Authors: Fan Tingting , Wang Shuo , Jiang Zongmin , Ji Shen , Cao Wenhua , Liu Wenli , Ji Yun , Li Yujing , Shyh-Chang Ng , Gu Qi
Published: November 2021

3D printing is an effective technology for recreating skeletal muscle tissue in vitro. To achieve clinical skeletal muscle injury repair, relatively large volumes of highly aligned skeletal muscle cells are required; obtaining these is still a challenge. It is currently unclear how individual skeletal muscle cells and their neighbouring components co-ordinate to establish anisotropic architectures in highly homogeneous orientations. Here, we demonstrated a 3D printing strategy followed by sequential culture processes to engineer skeletal muscle tissue. The effects of confined printing on the skeletal muscle during maturation, which impacted the myotube alignment, myogenic gene expression, and mechanical forces, were observed. Our findings demonstrate the dynamic changes of skeletal muscle tissue during in vitro 3D construction and reveal the role of physical factors in the orientation and maturity of muscle fibres.
Study on the linkages between microstructure and permeability of porous media using pore network and BP neural network
Authors: Liu Hao , Xu Ying , Wang Chengyong , Ding Feng , Xiao Haishan
Published: November 2021

In applying porous media air bearings (PMABs), designing the pore microstructure of porous media to obtain the desired permeability is challenging. The key parameters in this design are to map the pore microstructure characteristics to permeability and adapt to manufacturing process with the characteristics. For this purpose, a framework is proposed to characterize pore microstructure with morphology descriptor and predict permeability. 3D digital images of porous media are obtained using X-ray micro-computed tomography and various image construction techniques. The complex pore microstructure of porous media is represented with a pore network. Permeability is calculated based on the pore network. Sixteen pore microstructure morphology descriptors are initially calculated to characterize pore microstructure. A back-propagation neural network (BPNN) is built to learn the correlation between morphology descriptors and permeability. Pearson correlation coefficient (PCC) and feature importance scores of morphology descriptors are obtained based on the dataset and trained BPNN. The results demonstrate that the prediction performance of BPNN is excellent. The following six morphology descriptors (porosity, coordination number, average pore diameter, average throat diameter, average pore throat ratio, average throat length) are reserved to characterize pore microstructure. Finally, two types of pore microstructure are designed with the help of knowledge obtained by this research.
Thermal analysis of Kevlar/basalt reinforced hybrid polymer composite
Authors: Ramesh V , Anand P
Published: November 2021

Use of lightweight composite materials in automobile applications such as doors, bonnets, and bumpers and also the utilization of composite materials in building insulations require superior mechanical and thermal properties. This study attempts to determine the thermal conductivity, linear thermal expansion coefficient, heat deflection temperature and thermo gravimetric analysis of hybrid composite containing reinforcement fibers stacked in seven different combinations in an epoxy matrix as per ASTM standards. Each composite contained two different fibre materials, i.e., Kevlar and basalt. The study revealed that the stacked layers of basalt fibers had more influence on the thermal properties. It was observed that the hybrid composite made of least quantity layers of Kevlar and most of basalt exhibited the maximum thermal conductance of 0.219 W mK−1, while with vice versa laminate developed 0.191 W mK−1 which was least thermal conductance. The composition prepared by made Kevlar as core layer and basalt as its outer layers exhibited coefficient of linear thermal expansion above 11.5 × 10−6/°C. Maximum decomposition weight loss of 76.92% occurred in the composition prepared by keeping basalt as core and Kevlar as outer layer. The differential thermal graph showed that the said hybrid composite exhibited the peak decomposition rate of 1wt.%/°C. The thermal properties of the laminate prepared by keeping two layers of Kevlar sandwiched between the basalt were excellent when compared to other six hybrid composites investigated in this study.
Dye extracted from Bael leaves as a photosensitizer in dye sensitized solar cell
Authors: Alhorani Samah , Kumar Sarvesh , Genwa Mahaveer , Meena P L
Published: November 2021

This study has explored a new plant source, Bael tree leaves, as an efficient dye extraction towards green energy harvesting through dye-sensitized solar cells (DSSCs). The photosensitizers, photo-absorption, bandgap, and ionic conductivity characteristics of the extracted dye were determined using thin-layer chromatography (TLC), ultraviolet-visible spectroscopy, Tauc plot, and conductivity meter, respectively. Chlorophyll is the main constituent in the extracted dye confirmed by TLC analysis. An optimum concentration (0.2 g ml−1) with ionic conductivity of 455 μS cm−1 of the dye was used as a photoactive layer in DSSC, demonstrating power densities of 1.345 μW m−2 and 8.078 μW m−2 under the illumination of the LED lamp (1555 lx) and tungsten bulb (1926 lx), respectively. Additional parameters, including fill factor (0.26), ideality factor (1.25), characteristic resistance (309 Ω), series resistance (313 Ω), and shunt resistance (662 Ω) of the fabricated DSSC under tungsten illumination reveal that the novel Bael tree leaves-based dye can harvest green energy efficiently through DSSCs.
Setup of high resolution thermal expansion measurements in closed cycle cryostats using capacitive dilatometers
Authors: Rajak Neeraj K , Kondedan Neha , Jan Husna , Dilshah U Muhammed , Navya S D , Kaipamangalath Aswathy , Ramavarma Manoj , Bansal Chandrahas , Jaiswal-Nagar Deepshikha
Published: November 2021

We present high resolution thermal expansion measurement data obtained with high relative sensitivity of ΔL/L = 10−9 and accuracy of ± 2 % using closed cycle refrigerators employing two different dilatometers. Experimental details of the set-up utilizing the multi-function probe integrated with the cold head of two kinds of closed cycle refrigerators, namely, pulse tube and Gifford-McMahon cryocoolers, has been described in detail. The design consists of decoupling the bottom sample puck and taking connections from the top of the multi-function probe to mitigate the vibrational noise arising from the cold heads, using which smooth and high quality thermal expansion data could be obtained. It was found that dilatometer#2 performs a better noise mitigation than dilatometer#1 due to the constrained movement of the spring in dilatometer#2. This was confirmed by finite element method simulations that were performed for understanding the spring movement in each dilatometer using which the effect of different forces/pressures and vibrations on the displacement of the spring was studied. Linear thermal expansion coefficient α obtained using both dilatometers was evaluated using derivative of a polynomial fit. The resultant α obtained using dilatometer#2 and either of the closed cycle cryostats on standard metals silver and aluminium showed excellent match with published values obtained using wet cryostats. Finally, thermal expansion measurements is reported on single crystals of two high temperature superconductors YBa2Cu3−x
Al
x
O6+δ
and Bi2Sr2CaCu2O8+x
along the c-axis with very good match found with published data obtained earlier using wet liquid helium based cryostats.
Effects of cobalt deposition and pretreatment process on electrical properties of products
Authors: Xu Shaohui , Miao Haisheng , Zhang Jiandong
Published: November 2021

The preferable conditions for formation of high quality CoSi2 films and effect of process parameters on properties of products were investigated. The pretreatment should not only remove the natural oxide layer completely, but also could not damage Si substrate. The good static random access memory (SRAM) proportion of products is high when pretreatment thickness is 20 Å, reached 96.5%. The radio frequency (RF) bias power process parameter should also take an optimal value. When RF bias power is 150 W, the good SRAM proportion of products is greater than 98%. The 100 Å Co can just completely react with Si substrate after twice annealing (500 °C 30 s and 750 °C 30 s), and if it exceeds 100 Å, Co will be residual. Decreasing Co thickness leads to contact resistance (RC) increase whatever in N-well or P-well. The overall standby current (Isb) of product is least when Co thickness is 80 Å. Finally, the products achieved good electrical properties when Co thickness is 80 Å, pretreatment thickness is 20 Å and RF bias power is 150 W.
Magnetic excitation of high-Q resonance with split-ring resonators
Authors: Yan Jing-Chun , Zhang Shi-Qian , Zhang Yong , Wang Yu-Lin , Huang Cheng-Ping
Published: November 2021

Planar split-ring resonators (SRRs) with broken symmetry, excited by the electric field of incident wave, have been widely used to realize the high-Q resonance. In this paper, we report by theory and experiment an alternative scheme to induce the SRR-based high-Q resonance. The proposed scheme utilizes a two-dimensional array of vertical SRRs with vertical air gaps, which enables the excitation of narrow resonance with magnetic field and strong enhancement of local electromagnetic fields. The working mechanism correlates with the strong directional dependence of the dipole radiation (i.e., the elimination of electric-dipole radiation of the SRRs in the propagation direction), rather than the destructive interference due to the structural symmetry breaking. The dependence of Q factor on the structural parameters has also been studied theoretically, suggesting that a Q factor more than 2000 can be achieved. The results may be useful for designing narrow-band filters and sensors in the microwave or THz regime.