bluuebunny/crossref_metadata_2025 huggingface dataset:
Potential Biological Activities of Honey from Heterotrigona itama and Its Phytochemicals
Authors: Reskiani S , Rahmawati N R , Arung E T
Published: December 2023

Stingless bee honey is a nutritional source that is more popular presently as a substitute for forest honey, which is now limited to its natural sources. This study evaluates the potential biological activities and phytochemical contents ofHeterotrigona itamahoney obtained from 2 harvesting periods. The agar-well diffusion method was used for measuring the antibacterial activity, while DPPH free radical scavenging activity was used to measure the antioxidant activity. The phytochemical content of honey is analyzed based on the total phenolic and flavonoid contents. The results revealed that the honey collected during harvesting period 1 contained a total of 65.115 mg GAE/g honey and 136.03 mg CE/mg honey, while in period 2, it yielded 53.94 mg GAE/g honey and 181.08 mg honey, respectively. The results showed that honey samples at two harvesting periods had low free radical scavenging ability. Antibacterial assay againstPropionibacterium acnesindicated that the honey obtained from 2 harvesting periods possessed good antibacterial potential.
Production of bioelectricity from palm oil mill effluent through a dual chamber-microbial fuel cell system with the addition of Lactobacillus bulgaricus
Authors: Febriawan SD , Febriana AP , Yuniarto A , Purwanto M
Published: December 2023

Palm oil liquid waste has been successfully developed to produce bio-electricity with a dual chamber-microbial fuel cell system. This study utilized the Lactobacillus bulgaricus bacteria as a support for the substrate samples prepared in the anode chamber. Meanwhile, in the cathode chamber, KMnO4 electrolyte solution is used as an electroactive species that can capture electrons well. In addition, salt bridges fabricated from agar have a role as ion-exchange media in microbial fuel cells. The test results showed that the best performance was obtained in samples of palm oil wastewater with the addition of 10% Lactobacillus bulgaricus (LS/B-10) bacteria with current, voltage, and power density values of 0.9640 mA, 0.6760 V, and 248.04 mW/m2, respectively. The MFC system has also been proven to be able to reduce COD (Chemical Oxygen Demand) and TSS (Total Suspended Solid) levels, with the results of a reduction percentage of 42.6% and 7.2%, respectively, in the LS/B-10 variable treatment. All test results show that palm oil wastewater with the addition of Lactobacillus bulgaricus bacteria is promising for producing bioelectricity with a microbial fuel cell system.
The effectiveness of alkaline and thermo hydrolysis pretreatments in the bioethanol production from Calliandra calothyrsus wood
Authors: Nasriati N , Ufa M , Ningrum A F , Haqiqi M T , Suwinarti W , Amirta R
Published: December 2023

The demand in energy is increasing along with the development of technology. However, the utilization of fossil energy as the main current energy sources creates various environmental problems. Hence, it is important to search other energy sources which are environmentally friendly. One of the renewable energy sources is bioethanol produced from woody biomass. The purpose of this study was to investigate the suitability of Calliandra calothyrsus wood under development of alkaline and thermohydrolisis pretreatments. These pretreatments included the variations of 15, 30, 45 and 60 min at 121°C with NaOH concentration of 1, 2, and 3% (w/v). The chemical component analysis was conducted by using the TAPPI method, while the percentage of reducing sugar after saccharification was carried out by the Nelson-Somogy method. The results showed that the highest holocellulose content 60,62%, and the highest α-cellulose content was 64,30%. The highest pulp saccharification test results were obtained from 60 min pretreatment of 3% concentration of NaOH, which was 42,82% and 32,99% wood basis. The highest yield of ethanol potential was obtained from 36 hours saccharification, which was 139 L/Ton. Finally, it is suggested to do additional treatments with variations in concentration and temperature in order to obtain more optimal results.
Quality of Charcoal Briquettes from Sawdust Waste of Ulin (Eusideroxylon zwageri) and Coconut Shell (Cocos nucifera) Based on Variations in Ratio and Particle Size
Authors: Handayani S A , Widiati K Y , Putri F
Published: December 2023

The industrial revolution and the improvement in living standards of developing countries have caused serious environmental problems. Energy consumption has been steadily increasing over the years due to the increasing world population. Alternative energy is energy that does not come from fossil fuels. Charcoal briquettes are an alternative fuel made mostly from biomass. Charcoal briquettes, a mixture of sawdust waste of ulin and coconut shells, are alternative energy substitutes for fossil fuels. This study aims to determine the benefits of ulin and coconut shell as renewable energy such as charcoal briquettes, as well as determine the effect of variations in the ratio and particle size of ulin charcoal and coconut shell charcoal on the quality of charcoal briquettes. The research method uses a Factorial Experiment Design with 3 repetitions for testing moisture content, volatile substance levels, ash content, and fixed carbon levels. As for testing the calorific value, 2 repetitions were carried out. The results showed charcoal briquettes with optimal results were found in A1B5 treatment (particle size 40 mesh with a ratio of 100% coconut shell particle) with a moisture content value of 5.27%, ash content of 1.37%, and a calorific value of 6998.19 cal/g. The content, ash content, and calorific value produced from the briquettes have met SNI No. 01-6235-2000 standards.
The Impact of Land Cover Density on the Water Infiltration Process in the Nyadeng Lake Area, Merabu Village Berau District, East Kalimantan
Authors: Marjenah  , Matius P , Aprillius D , Mulyadi R
Published: December 2023

The sustainability of water resources depends on the state of the nearby forest. Land cover is essential for sustaining life systems in a region; the higher the quality of the land cover or forest vegetation, the greater the biodiversity value of the region. This research attempts to determine whether or not the vegetation in the Merabu Village area of Nyadeng Lake has the capacity to process the infiltration rate. The vegetation was sampled using simple random sampling, and a 20 m x 20 m plot was used to represent the area under investigation. Data collection was accomplished by establishing research plots that can represent the entire area or research area, with the size of the plot varying according to plant class. This research utilized a total of six plots. Three plots on the west and three on the east were laid out at a distance of five meters from the lake’s shore. The infiltration rate was measured by creating 0.5 m x 0.5 m infiltration subplots with five replicates per sample plot. These locations have been established approximately five metres away from the shore of the lake. High vegetation cover has a tremendously positive effect on infiltration. The coefficient of determination, with a value of 72%, indicates that the infiltration ability is influenced by the existence of vegetation to a significant degree.
Ameliorant application promotes growth performances of Calliandra calothyrsus Meissn. planted on post-coal mining land
Authors: Junaidi M , Syahrinudin  , Kiswanto  , Sudarmadji T , Ruchaemi A , Hartati W
Published: December 2023

Growth performances of plants raised on post-coal mining lands are highly hampered by the unfavourable environment conditions of plant root zones. This study was carried out to find out if the improvement of plan root environment conditions by the application of ameliorants may boost the growth performance (diameter and height) ofCalliandra calothyrsusduring 6 months after plantation. Twenty-seven replicates of 3 levels of ameliorant treatments (0%v + 0%v, 10%v + 20%v, and 20%v + 10%v of solid decanter + biochar for the M1, M2, and M3, respectively) were applied in compatible arrangement with completely randomized design (CRD) procedure. In each replication, 30 seedlings were planted at 1 m x 2 m spacing. Plant diameter and height were census, a normal distribution test was employed prior to the anova test and mean different was defined by the LSD test. Results showed that diameter growths were significantly affected by the treatment applied. M1, M2, and M3treatments gave a 1.32 cm, 1.29 cm, and 1.69 cm diameter growth, respectively; and gave a 147.4 cm, 142.6 cm, and 161,9 cm height growth, respectively. We conclude that M3treatment is a promising ameliorant application to develop further in raisingC. calothyrsuson post-coal mining lands.
Enriched biochar enhances height growth performance of Anthocephalus cadamba on severely degraded Spodosols in East Kalimantan
Authors: Putra MOPS , Syahrinudin  , Hartati W , Kiswanto  , Sudarmadji T , Sofyan FPM , Hapsari MT
Published: December 2023

Tropical Spodosols are highly fragile and disturbed Spodosols remain unproductive at conventional management practices due to the inherent infertility of the soils. These soils developed from quartz rocks and are characterized by the presence of E albic and B spodic horizons. This study was conducted to determine the effect of enriched biochar application on height growth of jabon (Anthocephalus cadamba) stands planted on spodosols. Research plots were arranged to comply with a 2-factors completely randomized design (CRD) procedure – 3 levels of rate of biochar treatment (A1= 0%v, A2= 2%v and A3= 5%v) and 2 levels of liquid organic fertilizer enrichment (B0= without enrichment and B1= with enrichment). There were 3 replicates for each treatment consisted of 28 Jabon (Anthocephalus cadamba) plants at 2.5 m x 3 m spacing, therefore a total of 504 plants were observed in this study. Results showed that the rate of biochar and nutrient enrichment gave a significant effect on the height growth of jabon plants (A. cadamba), the best height growth was obtained at the enriched biochar treatment rate of 5%v (A3B1).
Silvicultural decisions to formulate forest restoration strategies using geospatial approaches
Authors: Kiswanto  , Mardiany  , Ariyanto  , Tsuyuki S
Published: December 2023

Restoring deforested and degraded forests is mandatory to guarantee the future of tropical forests. In this study, we formulated silvicultural strategies for restoring tropical forest ecosystems using geospatial approaches to detect deforested and degraded forests based on landscape circumstances. Depending on the overlaid map of the current land cover and its land status, we categorized our forest restoration activity map into three main groups: reforestation, forest rehabilitation, and none. Based on the forest vulnerability, as evidenced by slope and erosion risk, we also allocated the ranks of restoration location into three priorities: first, second, and third. We believe that geospatial modeling maps can assist decision-makers in selecting locations and the most important goals for reforestation in order to reduce greenhouse gas (GHG) emissions in land-based sectors. In order to exactly convey the geospatial data of forest at more detailed landscape scales, such as sub-district and village levels, as well as forest management units, these study need to be enhanced using high-resolution satellite or aerial imageries.
Good practices of post mining land rehabilitation works in the southern region of East Kalimantan, Indonesia
Authors: Sudarmadji T , Hartati W
Published: December 2023

Open-pit/cut/cast mining is a method of extracting coal directly from the surface using a series of level benches to reach the deposit close to the surface overlain by relatively thin vegetation, topsoil, and rocks. During the year of 2010 - 2017 PT Kideco Jaya Agung (KJA) has rehabilitated post mining land 1.379,54 ha in area. The objective of this study was to examine practices of degraded land rehabilitation works and understand good practices of post mining land rehabilitation at minedout forest lands. A number of 750 plots (25mx40m) were established in 2022 to evaluate practices of land arrangement, soil erosion and sedimentation control, and land revegetation works. Rehabilitation activities that have been going well based on established plan were: waste dump arrangement, topsoil spreading, cover crops planting, plant growth rate, number of plant per-Ha, and plant health. However, rehabilitation works that still require improvement were slope stabilization, number and benefits of soil and water conservation infrastructures, excessive soil eronsion, and the composition of long life and fast growing plant species. The evaluation score of post mining rehabilitation works was 22,5 for land arrangement, 17,5 for soil erosion and sedimentation control, and 48 for land revegetation respectively with the total score 87,5. The total score indicates that forest rehabilitation works has been carried out properly based on good practices of coal mining principles.
Soil organic carbon stores in the mangrove forest restoration of ex-ponds in the Salo Palai Village of Kutai Kartanegara
Authors: Jansi B T , Kiswanto  , Mardiany  , Diana R
Published: December 2023

Mangrove forests in the Mahakam Delta have traditionally been used by people for a variety of purposes, including fuel, hut construction, and charcoal production. Such use is still acceptable as long as it does not reach commercial scale. Where mangrove forests have greater potential for carbon absorption when compared to dry land. In this study, several analyses of bulk density, soil carbon (%), total soil organic carbon (g/cm2), total soil organic carbon (tonnes/ha) were analysed from 3 points with 3 depths (0-50.50-100.100- 150). Then an analysis was carried out using the t test to test whether there was a very significant difference or not. The results of this study showed that ponds without rehabilitation had a total bulk density value of 7.16 g/cm2 with a total soil organic carbon store of 0.34 tons/ha. In the former ponds the rehabilitation area has a total bulk density value of 8.64 g/cm2 with a total soil organic carbon store of 1.01 tons/ha. Based on the results of the t test analysis, it shows that t count > t (0.01) so that it can be said that rehabilitated former ponds provide a very significant difference to carbon storage.
Management and application of specific location food crop technologies based on ecoregional dry land in central Sulawesi (A Review)
Authors: Syafruddin  , Amin M , Susilawati  , Saidah  , Wahyuni A N , Rahayu H P S
Published: December 2023

To achieve food self-sufficiency and food independence, government has been implementing some programs. Those programs generally face two basic problems, namely: 1. A high conversion of paddy fields in to industries and housing area which are in line with the growth of population. 2. Global climate change which causes more frequently of drought and floods in both dry and lowland farming. Dry land is very extensive in Central Sulawesi which can be used as a new source of food production to reach food self sufficiency, while it has not been optimally utilized yet. Thus, Central Sulawesi Province has potency to become a food buffer region in Indonesia by optimizing the utilization of dry land along with the application of specific location technologies. Some technologies which could be simultaneously applied in dry land are high-yield varieties selection, improving cropping patterns, rotation of varieties, modification of cropping systems, and specific location fertilization. This article will discuss or review the results of research that have been carried out in dryland management, the use of adaptive superior varieties, and planting patterns that can significantly increase land productivity and farmer income. So comprehensive planning is needed to improve and optimize the use of dry land. To speed up technology in certain locations, a collaboration between local governments, especially extension services, research institutions and universities is needed to encourage the production and productivity of food crops in dry lands.
The effect of arbuscular mycorrhizae inoculation on growth and yield of red chili on the highland andisol soil
Authors: Rosliani Rini , Prathama Mathias , Sulastrini Ineu , Amisnaipa  , Sugiartini Emi , Dahlan Santosa Ade
Published: December 2023

One effort to improve soil fertility and plant productivity is through the inoculation of arbuscular mycorrhizae. Mycorrhizae plays a role in increasing the absorption of phosphorus elements in the soil. The study aimed to determine the effect of the inoculation of arbuscular mycorrhizae on increasing the growth and production of chili. The experiment was carried out in the highlands of West Bandung in 2017-2018. The experimental design used was a randomized completely block design (RCBD) with 5 treatments and 5 replications. The treatments consisted of control, 2 kg/m2 mycorrhizae in the nursery, 4 kg/m2 mycorrhizae in the nursery, 10 g/plant mycorrhizae at transplanting, and 20 g/plant mycorrhizae at transplanting. The mycorrhizae used wasGlomussp. in the form of inoculum (soil as a carrier). Variables observed included soil chemical properties, degree of root infection, vegetative growth, and yield of chili. Data were analyzed using analysis of variance (anova) and continued with Tukey’s Honestly Significantly Difference (Tukey’s HSD) test at 5% significancy level. The results showed that the inoculation of mycorrhizae to andisol on low P soils increased soil P availability, degree of root infection, vegetative growth, and red chili production, but high doses hurt chili yields. The inoculation of mycorrhizae doses of 2 kg/m2 in the nursery and 10 g/plant at transplanting can increase red chili production by 13.19% and 15.59%. To see the effectiveness of mycorrhizae more clearly, it is suggested to test mycorrhizae on chili in the dry season and on marginal soils.
Utilization of agricultural waste as hydroponic media for the Deep Flow Technique system and combination of nutrients for shallot plants from seeds
Authors: Saidah  , Andi Nirma W , Damayanti A. , Muchtar  , Amalia Anugerah F. , Padang Irwan S. , Risna  , Nurmasitah  , Dalapati A. , Suwitra IK , Syafruddin  , Boy Ruslan , Tina F , Rahayu Heni SP
Published: December 2023

Hydroponics is one of the planting systems without using soil as a medium. This system is developing in urban areas where the availability of land is very limited. Suitable planting media and the availability of nutrients to the needs of plants are important in cultivating plant with hydroponic systems. This study aims to determine the effect of planting media and the combination of AB Mix nutrients on the growth and yield of shallots from seeds in the Deep Flow Technique (DFT) system. The research was conducted in Maku village, Dolo sub-district, Sigi district, Central Sulawesi, from February to May 2021. The research used a Split Plot Design, where the main plot was the planting media and the subplots were the combination of nutrients. The planting media used were rockwool, husk charcoal, and cocopeat. While the nutrients are given vegetable nutrition for three months, fruit nutrition for three months, vegetable nutrition for two months + fruit nutrition for one month, vegetable nutrition for one month + fruit nutrition one month with four replications. The observation components were plant height, number of leaves, number of tubers per clump, tuber weight per clump, tuber weight per seed and tuber diameter. The results showed that the treatment of planting media types and nutrient combinations had different effects on each observation component. The best treatment was husk charcoal media given vegetable nutrition at the age of one month and fruit nutrition at the age of two months.
Nano Biochar Coating Methods of Urea Type to Increase the Growth and Yield of Shallot
Authors: Hariyono  , Isnawan B.H , Mulyono  , Darmawan BE
Published: December 2023

Shallots are an agricultural commodity with high economic value and demand in Indonesia. This study aims to determine the effectiveness of nano-biochar coating of several types of urea as nitrogen slow release to increase growth and yield of shallot in coastal sandy land. This research was conducted in the Agricultural Experiment Grenn House of the Muhammadiyah University of Yogyakarta from March to June 2022. This method was experimental research using a single-factor design arranged in a Completely Randomized Design (CRD); there were six treatments. Each treatment consisted of 6 plant samples with three replications, namely Urea Prill (A), Nano Biochar Coated Urea Prill (B), Urea Granules (C), Nano Biochar Coated Urea Granules (D), Urea Tablet (E), Nano Biochar Coated Urea Tablet (F). The results showed that the nano biochar coconut shell-coated urea prill effectively increases the growth and yield of shallots in coastal sandy land. In the future, nano biochar-coated urea prill can be applied to increase urea effectiveness and shallot yields.
Diversity and Population of Weed Propagule in Two Rice Cropping Systems
Authors: Setiawan A N , Isnawan B H , Febrianita N , Santi I S
Published: December 2023

Weeds can reduce rice yields by 20-89%, mainly due to competition for nutrients, water, sunlight, and growing space. Weeds that grow in rice fields come from propagules previously in the soil. Seedlings are formed from the previous season, so the cultivation system greatly affects them. This study aims to determine the diversity and population of weed propagules in upland rice and lowland rice. This research was conducted by survey method in Semanu District, Gunungkidul Regency, Special Region of Yogyakarta, by taking soil samples from three plots of upland rice and lowland rice paddy. Soil sampling was conducted four times before tillage, 3, 6, and 9 weeks after planting. The results showed that the diversity of weed propagules in upland rice was higher than in lowland rice fields with more weed propagule species. Annual terrestrial weed propagules dominate in upland rice, while in lowland rice fields, it is dominated by annual aquatic weed propagules. The diversity index of weed propagules in upland rice and rice paddy is included in the medium criteria. The number of species and individual propagule weeds in upland rice is more than in the upland rice fields. The results of this study can be used as a basis for proper weed management so that it does not disturb and harm rice plants.
Rice (Oryza sativa L.) response with the Application of Manure and Liquid Organic Fertilizer
Authors: Isnawan B.H. , Aini L.N. , Hanudin E. , Basanti P. V.Z.
Published: December 2023

Organic fertilizers are necessary for environmentally friendly agriculture. The study aimed to determine rice response to manure and liquid organic fertilizer application ratio. The study was conducted by experimental method with a Complete Randomized Design with five replications. The treatment consists of 6 treatments, namely organic fertilizer, 25% goat manure + 75% commercial liquid organic fertilizer, 50% goat manure + 50% commercial liquid organic fertilizer, 75% goat manure organic + 25% commercial liquid organic fertilizer, 100% goat manure, and 100% manure goats + 100% commercial liquid organic fertilizer. The results showed that plant height during the middle of the vegetative phase treatment of 25% goat manure + 75% commercial liquid organic fertilizer was higher than the treatment of 50% solid organic fertilizer goat manure + 50% commercial liquid organic fertilizer and 100% treatment of goat manure solid organic fertilizer. The root length and volume of treatment 25% goat manure + 75% commercial liquid organic fertilizer is longer and higher than the combined treatment of manure and other liquid organic fertilizers. The grain weight per clump of mixed manure and liquid organic fertilizer treatment is no different. In the future, treatment of 25% goat manure + 75% commercial liquid organic fertilizer can be applied to increase the rice roots.
Growth and response of several shallot varieties to its important diseases in Lembang highlands
Authors: Saadah I R , Korlina E , Waluyo N , Sulastrini I , Gunaeni N , pinilih J , Karjadi A K
Published: December 2023

Disease attacks on shallots (Allium cepa L. var. aggregatum) are one of the main constraints on increasing shallot production. Important diseases that often appear in shallots are purple blotch disease (Alternaria porri), leaf blight (Stemphylium vesicarium), and downy mildew (Peronospora destructor). The diversity of existing varieties is wealth as a substitution for seed sources. The aim of this study was to determine the growth and disease resistance of several shallot varieties grown in Lembang highlands. The research was conducted at the Margahayu Experiment Field of the Indonesian Vegetable Research Institute Lembang, from March to July 2021. The Randomized Block Design (RBD) was used in this study with a treatment consisting of 11 varieties of shallots (Violetta 1 Agrihorti, Violetta 2 Agrihorti, Violetta 3 Agrihorti, Ambassador 1 Agrihorti, Ambassador 2 Agrihorti, Ambassador 3 Agrihorti, Ambassador 4 Agrihorti, Maja Cipanas, Pancasona, Kramat 1, and Sembrani), with 3 replications. The results showed that the growth performance varied between varieties. The Violetta 3 Agrihorti was the highest for plant height, the highest number of tillers was in the Pancasona, and the highest number of leaves was in the Ambassador 3 Agrihorti. Among the eleven shallot varieties tested at high altitudes, none were resistant to the diseases of Alternaria porri, Stemphylium vesicarium, and Peronospora destructor, except for the Pancasona variety which was classified as tolerant (resistance category included in the susceptible category, but has high yield). Meanwhile, for disease resistance, the Violetta 1 Agrihorti is relatively resistant to purple blotch disease, leaf blight, and downy mildew.
Nano-emulsion of three essential oils as the potential eco-friendly control to Phytophthora capsici
Authors: Warman Riki , Manohara Dyah , Noveriza Rita , Pribadi Ekwasita Rini , Melati
Published: December 2023

Phytophthora capsiciis a plant pathogenic oomycete that causes significant damage to many crops, including black peppers, chili, cucurbits, and tomatoes. This pathogen is widespread and can survive in soil and plant debris for several years, making it difficult to control. The aim of the research was to observe the effectiveness of three essential oils as nano-emulsion formulas (NS, NC, NE and NA) against the growth ofP. capsiciin vitro and in vivo. In vitro testing was carried out using 2 methods, namely the poison food and volatile disc assay. Testing of active ingredients using the GCMS method and measuring active ingredient particles using the DLS method. In vivo testing was carried out on chili seeds to determine their growth and germination. The result indicated that all nano-emulsions at 0.50% inhibited the growth ofP. capsiciwhich varied between 33,25% to 88,50%. The NC, NS, and NA formula caused complete mycelial growth inhibition at a concentration of 1.0%. Total inhibition of growth also occurred with volatile compounds produced by NS and NA formula. The NC, NS, NE and NA formulas are not phytotoxicity to chili seeds and their germination. Therefore, three essential oils (NC, NS, NE) and the mixture of them (NA) are potential to be used in managingP. capsicias eco-friendly control and possibly as an alternative to synthetic fungicides.
Controlling Armyworm (Spodoptera exigua) (Lepidoptera: Noctuidae) on Shallot using Nano Husk Ash
Authors: Hidayat T , Medina EN , Mulyono  , Utama NA
Published: December 2023

The Beet Armyworm (Spodoptera exigua) is a polyphagous defoliator that poses a significant threat to cultivated plants, particularly shallot crops. Its attacks during the vegetative phase cause substantial damage. To control this pest, farmers often resort to synthetic pesticides, leading to negative consequences such as resistance development. To address consequences, internal control measures, like enhancing plant resistance through beneficial nutrients like silica, are crucial. Silica has been known to improve plant resistance against pest attacks. This study aims to investigate the effects of various methods of applying nano-sized rice husk ash fertilizer on the growth and resistance of Biru Lancor cultivar of shallots against S. exigua. Nano-rice husk ash fertilizer with an average particle size of 65,326 nm was produced and applied using three methods: placement, foliar, and seed coating. The results demonstrated that all methods of nano-rice husk ash application increased plant resistance, reducing leaf damage and pest mortality. The foliar application yielded the best results, enhancing plant height and epidermal cell wall thickness. Furthermore, nano-rice husk ash application positively influenced shallot productivity. This study highlights the potential of nano-sized rice husk ash as a sustainable and effective internal control measure against S. exigua, complementing synthetic pesticides for shallot pest management.
Root colonization by vesicular arbuscular mycorrhizal in different dosage forms and effect on C3 plants root morphology
Authors: Akib Muh. Akhsan , Syatrawati  , Prayudyaningsih Retno , Kuswinanti Tutik , Syaiful Syatrianti A. , Mustari Kahar
Published: December 2023

The application of vesicular arbuscular mycorrhizal (VAM) in powder dosage form has been used for a long time. However, this dosage form has a non-uniform application dose and allows VAM spores to be lost through wind and rainwater, so innovation is needed in the VAM dosage form. A study aimed at knowing dosage forms of VAM as a biological agent that affects colonization level and C3 plant‘s root morphology was carried out at Screen House Laboratory, Faculty of Agriculture, Animal Husbandry and Fisheries, University of Muhammadiyah Parepare using a factorial design based on completely randomized design (CRD). Treatment of VAM dosage forms (factor 1) used was powder (A1), sachet (A2), and tablet (A3). While the C3 plant species (factor 2) used were Puraria japonica (B1), Vigna radiata (B2), and Amaranthus gangeticus (B3). Observations were conducted on the percentage of colonized roots and the C3 plants’ root morphology. The results showed that the combined treatment of VAM dosage forms (powder, sachet, and tablets) and C3 plant species (Puraria javanica, Vigna radiata, Amaranthus gangeticus) showed significant effects on colonized roots percentage and C3 plant root morphology. So it can be recommended that VAM dosage forms (sachet and tablet) are efficient and effective for the mobilization and field application of VAM.
Life Cycle and Morphometric Analysis of Yellow Assassin Bug Cosmolestes Pecticeps Stal (Hemiptera: Reduviidae) Feed on Elaeidobius Kamerunicus Faust (Coleoptera: Curculionidae)
Authors: Pradana M G , Priwiratama H , Rozziansha T A P , Lestari F C , Nasution U , Asmanizar A , Nurkomar I
Published: December 2023

Elaeidobius kamerunicus is an important insect in oil palm ecosystems, as it is the primary pollinator of oil palm flowers. Oil palm is an economically important crop, and its cultivation requires the successful pollination of its flowers to ensure high yields. Without the pollination services of insects such as E. kamerunicus, oil palm production would be significantly reduced. Additionally, E. kamerunicus is known as a food source for the yellow assassin bug Cosmolestes pecticeps. Understanding the interactions between E. kamerunicus and predators such as the yellow assassin bug is crucial for the sustainable management of oil palm ecosystems. This study aims to provide preliminary data on the yellow assassin bug’s life cycle and feeding habits, focusing on its prey, E. kamerunicus, and morphometric analysis. We found that E. kamerunicus is a common prey of the yellow assassin bug, and its feeding habits significantly impact the ecology of its inhabited areas. Our study provides valuable insights which could be useful for future research in the field. Understanding the interactions between the yellow assassin bug and E. kamerunicus in oil palm ecosystems is important to manage and maintain their ecological balance effectively in supporting sustainable agriculture.
Design and Multi-objective Optimization of Vibro-Pneumatic Separator for Paddy Pre-Cleaning using RSM
Authors: Hajad M , Amrullah R H , Dzulkifli M
Published: December 2023

Development of vibro-pneumatic separator machine considering both machining parameter and characteristic of grain product was presented in this paper in term of multi-objective optimization. Design of separator machine combines both pneumatic part to separate the light impurity contaminant and multilevel vibrating sieve to separate other type of contaminant for pre-cleaning purpose. Machining parameters such as airflow rate, vibration frequency and moisture content are investigated in this paper to analyze its effect on separation efficiency and product losses. The research was based on Response Surface Methodology (RSM) with 3 continuous factors and 3 levels of each factor. The experiment revealed that airflow rate, vibration frequency and moisture content were found significant on separation efficiency and product losses. It confirmed that the quadratic polynomial model were good at R-squared of 95.97% for the separation efficiency and 96.42% for product losses. Based on the RSM response optimizer, the optimal condition can be achieved using the setup of the airflow rate at 4.3 m/s, the moisture content at 8% and the vibration frequency at 20 m/s. The optimum setup promised the separation efficiency of 89.1% and the product losses of 3.6%. This parameter setup can be used in terms of design purpose and setup the optimum parameter of vibro-pneumatic separator machine that can be used for various grain material pre-cleaning process for a sustainable rice production.
Characteristics of marine organic waste compost using Brunauer-Emmet-Teller, Fourier Transform Infrared, and Scanning Electron Microscope-Energy Dispersive X-Ray
Authors: Sebayang N U W , Hidayat B , Jamilah  , Sari S P
Published: December 2023

On the basis of their composition, organic waste and inorganic waste may be differentiated from marine debris. Microorganisms have the ability to break down organic waste, hence marine organic waste can be bio-converted into compost. The goal of analyzing the properties of compost from marine organic waste was to characterize the organic components with FTIR, identify the surface area, pore diameter, and total pore volume of the compost, and evaluate the microstructure with SEM. The result with BET that marine organic waste compost has a surface area of 22.690 m2/g that has the potential for greater adsorption capacity. FTIR test show that chemical content in marine organic waste compost included 15 types of vibration with different wavenumber and %transmittance. The results of the SEM-EDX test for organic waste compost have that the main components of marine organic waste compost are Carbon, Oxygen, Magnesium, Aluminium, Silicate, Potassium, Calcium and Iron. The morphological structure of the SEM compost 1000x includes the structure of a very dense raw material mixture and herds, with 2500x; 5000x and 10000x cover a granular, porous, and fragmented structure which means that there is more space pore in the compost which is good as an adsorbent.
Flow over a step cylinder using partially-averaged Navier-Stokes equations with application towards dynamic subsea power cables
Authors: Shaukat U , Schnepf A , Giljarhus K E T
Published: December 2023

Understanding the flow characteristics of buoyancy sections in power cable and umbilical configurations is crucial for analyzing floating offshore wind turbine systems. Buoyancy sections decouple the motions from the floater and the destination point to ensure the integrity of the system. Using accurate drag coefficients in their design is essential, as they significantly impact the overall behavior of the configuration. Therefore, Computational Fluid Dynamic (CFD) analysis is performed in the present study on a single buoyancy module attached to a power cable represented by a step cylinder configuration. The Partially-Averaged Navier-Stokes (PANS) turbulence model is applied. Its accuracy is validated against experimental findings of a wall-mounted cantilever cylinder and an infinite cylinder. The numerical results reveal that the larger diameter cylinder (LDC) section reduces the drag experienced by the smaller diameter cylinder (SDC) section near the junction. The LDC has a sharp, chamfered, and filleted edge replicating the various shapes of buoyancy modules. The edge design of the LDC affects the drag forces and flow patterns. The SDC has an 8% lower drag coefficient in the fillet edge case than the sharp edge case. The drag coefficient is 3.5% lower for the LDC in the filleted edge case than the sharp edge case. The sharp edge causes a significant separation of the fluid upstream of the SDC. However, this separation is notably reduced when the LDC has a chamfered or filleted edge. Detailed drag coefficients for buoyancy section analysis of power cable configurations have been deduced from the presented results.
A novel design of a hybrid glulam-steel substructure for the IEA 15-MW floating wind turbine
Authors: Yousef H H , Ma Y , Patel K S , Xing Y
Published: December 2023

Wind energy has become increasingly recognised as a very promising type of renewable energy. In addition, floating offshore wind turbines have facilitated the development of electricity production in intermediate (45-150 m) and deep sea (>150 m) depths. Despite this, wind turbine manufacturing, installation, and operation may generate substantial greenhouse gas emissions. A novel hybrid glulam-steel floating substructure design is presented in this research, intended for the IEA 15 MW floating wind turbine. The objective is to contribute to advancing floating wind energy while minimising costs and carbon dioxide emissions. The objective of the novel design is to substitute steel with glued laminated lumber (glulam). It showcases an altered iteration of the UMaine VolturnUS-S semi-submersible platform originally created for the IEA 15 MW turbine. Before selecting one of three preliminary hybrid wood-steel models, the Ansys Workbench 2020 R1 is used to evaluate and appraise them per a set of criteria extracted from pertinent timber and steel standards. The chosen hybrid design conserves about 590 metric tonnes of steel mass compared to the UMaine VolturnUS-S semi-submersible platform. The selected model is then validated by executing a fully coupled aero-hydro-servo-elastic dynamic analysis with OpenFAST. Consideration is limited to the ultimate limit state design (ULS) for normal and severe operating situations. The utilisation factor of the glulam supporting structure for the IEA 15 MW turbine ranges from 74% to 94%, indicating that it is an effective load-bearing solution.
Numerical analysis of semiconductor-based energy conversion technologies for offshore applications
Authors: Choi T , Lee J H , Kim T Y
Published: December 2023

This study analyzes the physical principles and characteristics of thermoelectric energy conversion phenomena utilizing p-n semiconductor couples to propose a design methodology for thermoelectric generators (TEGs) capable of energy recovery in marine environments. To design TEGs with practical power generation and energy conversion efficiency, the development of a numerical analysis model that can predict and analyze the behavior characteristics of TEGs is required. We present the necessary conditions for a numerical analysis model that simulates the generation characteristics of TEGs at the system level, along with a comparison and analysis of experimental results. The electrical connection method of the thermoelectric modules (TEMs) significantly affects the power generation performance of TEGs; however, there is a lack of research on the electrical connections between TEMs in existing studies. This paper examines the reasons for performance changes due to electrical connections between TEMs and proposes an optimal electrical connection method. Additionally, it is demonstrated that improving the thermal flow distribution within the TEG can enhance system performance and maximize the effects of electrical connections between TEMs. We analyze the characteristics of technologies that can improve the level of thermal flow distribution within the TEG, such as finned and porous structures, and present optimal utilization strategies.
Selecting the inlet configuration for gas-liquid cylindrical cyclone separator
Authors: Sy L V , Lan N T
Published: December 2023

Gas-Liquid Cylindrical Cyclone Separator (short for GLCC) is a compact separator that has been widely used in petroleum production. The inlet configuration has significant impact of the GLCC capacity separation. By utilization of both FEM simulation and practical experiments, three inlet configurations and twelve inclined angles are investigated to find the steadily operating inlet configuration for industrial applications. In this study, the flow pattern and kinematic behaviour of each configuration are thoroughly analysed. Besides, the distribution of three velocity components of the body flow in GLCC is compared with one of the practical experiments. The result shows that the current inclined-inlet angle of 27° is not the steadily operating angle for industrial applications. In steady, it is a range of inclined inlet angle from 0° to 35° for three inlet configurations. The dual-inlet configuration indicates better properties for separating efficiency.
Assessment of a novel PTO system for swell energy convertors using digital twin modelling
Authors: Ren C , Xing Y , Moen L
Published: December 2023

There is no lack of ideas and prototypes for wave energy converters (WECs). However, existing WECs are designed to extract energy from waves at normal to high frequencies and typically focus on close-to-shore steep waves and short wavelengths to gain a frequent movement of interactive components. This limits the size of the buoyancy structure and results in the need to use many generating units to achieve a high-power output. We reverse this focus in small and coastal WECs mentioned above by harvesting swell energy through the Swell Energy Convertor (SWC). SWC uses an innovative power take-off (PTO) system, which Ocean Energies AS invented. This patented crankshaft mechanism transforms the linear motion from ocean waves into rotation for rotating a generator. When combined with a large buoy structure, this PTO system allows the SWC to focus on the swells (large wavelengths and low to high wave heights) further offshore and reduce/remove the drawbacks associated with the abovementioned coastal areas. The SWC (i) focuses on the high energy swells offshore, (ii) uses large buoy structures in combination with slight vertical movement, and (iii) can optimally extract energy in any direction. This results in SWC being a far less complex system with a much higher power output than existing WECs, which will significantly lower the cost of WECs. The SWC will target the area between Greenland and Scotland, with significantly high wave energy above 60 kW/m. This paper will present the design and analysis of the proposed PTO system in the SWC. First, the PTO model and working mechanism will be described. Second, a digital model of the PTO system will also be introduced. Third, three optimal design candidates are selected and analysed further to provide a deeper insight into the PTO design. Last, discussions and planned future works are presented.
Research on dynamic responses of mooring line system of semi-submersible platforms in Vietnam sea conditions using random model
Authors: Pham H H , Mai T , Liu Y
Published: December 2023

Recently, due to the nearshore oil fields in Vietnam were nearly exhausted, oil and gas extraction proceeds to deeper water areas using the mooring floating offshore structures. Therefore, the durability of the mooring system in deep water should be studied through determining the dynamic tension of the mooring line system using random wave models. However, full stochastic dynamics analysis for mooring line system takes up a lot of time and requires large computing resources. This paper is going to study the hydrodynamic interaction of random waves onto a semi-submersible platform, thereby analysing the dynamic responses in time domain of the mooring system using the “time window” method to optimize computational time and computing resources. This method performs the dynamic simulations around the maximum quasi-dynamic tension values to determine the dynamic tension and the dynamic amplification factor (DAF) of a maximum load-bearing mooring line, thereby evaluating the dynamic responses for the whole mooring system. The method is applied to calculate for a semi-submersible platform in Dai Hung field in Vietnam Sea.
Numerical study on the de-ballasting operation of a floating dock with a malfunctioning pump
Authors: Zhang J , Wen X , Ong M C
Published: December 2023

In normal de-ballasting operations of floating docks, each ballast pump manages a specific group of ballast tanks, independently of the others. However, if one pump is malfunctioning, a connection valve between the group and its adjacent group is opened, allowing its adjacent pump to control two groups of tanks simultaneously. This study aims to investigate the de-ballasting dynamic process in the event of a ballast pump malfunction by utilizing a numerical model of a full-scale digital floating dock. In the present numerical model, the dock is represented as a rigid body with six degrees of freedom and is subjected to hydrostatic, hydrodynamic, and mooring forces. To maintain pitch and roll angles within predefined limits, a modified P-controller is employed to regulate the valve opening angles at all the ballast tanks. Hydraulic calculations for the ballast water system with a malfunctioning pump are conducted, and the numerical results demonstrate the effectiveness of the present modified P-controller when dealing with a malfunctioning Pump No. 1.
Fixed type-oscillating water column front wall angle variation and impact on chamber performance: CFD numerical wave tank assessment
Authors: Samitha Weerakoon A H , Thilan W , De Silva H A , Assadi M
Published: December 2023

This study investigates optimizing the front wall geometry of an Oscillating Water Column (OWC) chamber to enhance turbine performance and output efficiency when harnessing energy from progressive waves with consistent periods and wavelengths. Numerical Wave Tank (NWT) adopted simulations carried out using ANSYS-Fluent ® package, VOF method with multiphase flow (air-water) where 2-D wave motion of NWT implemented using a C+ computer code. Frontal wall angle of the air/water chamber changed from 0° to 80°, for 10 cases. OWC system was most effective in harnessing and converting wave energy at 0° angle, reaching the maximum power output of 605.08 W/m. In contrast, 80° angle exhibited lower efficiency, with the lowest power output of 26.55 W/m. The average power output over time reflects consistent energy conversion, with the 0° angle demonstrating the highest average power output of 123.72 W/m, while the 80° case exhibited less efficient pneumatic power potential with an average of 3.5 W/m. A uniform cross section provides higher pneumatic power when with PTO in OWC. The efficiency of power generation can be increased by approximately 10 to 20% by keeping 0 to 10° angle of front wall without any appendages fitted with into the wall.