• Journal of the Korean Wood Science and Technology
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• v.47 no.3
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• pp.324-335
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• 2019

Timber from plantation forests has inferior physical and mechanical properties compared to timber from natural forest because it is mostly from fast-growing tree species that are cut at a young age. Filling cell voids with methyl methacrylate (MMA) can improve the wood properties. The purpose of this study was to determine the physical and mechanical properties of MMA-impregnated wood from three fast-growing wood species, namely jabon (Anthocephalus cadamba (Roxb.) Miq.), mangium (Acacia mangium Willd) and pine (Pinus merkusii Jungh. & de Vriese). Wood samples were either immersed in MMA monomer or impregnated with it and then heated to induce the polymerization process. Jabon, which was the lowest density wood, had the highest polymer loading, followed by pine and mangium. The physical and mechanical properties of samples were affected by wood species and the presence of MMA, with higher-density wood having better properties than wood with a lower density. Physical and mechanical properties of MMA wood were enhanced compared to untreated wood. Furthermore, the impregnation process was better than immersion process resulting the physical and mechanical properties. Based on MOR values, the MMA woods were one strength class higher compared to untreated wood with regard to Strength Classification of Indonesian Wood.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.1055-1062
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• 2021

This study aims to determine the effect of consumer preferences and awareness on interest in organic vegetables. Factors observed in this study were information, consumer preferences, consumer awareness, and consumer buying interest toward organic vegetables. This research uses descriptive quantitative method. The data sampling technique uses accidental sampling method. The data was collected from respondents consisted of 100 consumers of five major retailers in the city of Bogor in Indonesia. The respondents consist of 80 female (80%), and 57 respondents are 25-34 years old (57%). In terms of education, type of job and monthly income of respondent, the sample can be categorized as middle-class segment. The data obtained were analyzed using Structural Equation Modeling with Partial Least Square (SEM-PLS). The results of this study indicate that the information obtained by consumers significantly and positively affects consumer preferences and consumer awareness of organic vegetables. Then, consumer preferences and consumer awareness significantly and positively affect the interest of consumers to buy organic vegetables. Consumer preference for organic vegetables is still considered quite low. The factors that influence the low consumer preference are the price of organic vegetables, which is more expensive than non-organic vegetables and the unattractive packaging of organic vegetables.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.9
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• pp.351-360
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• 2022

This study aims to determine the factors that can influence investors in selecting stocks in the Indonesian capital market to establish an optimal portfolio, and find phenomena that occurred during the COVID-19 pandemic so that buying interest / the number of investors increased in the Indonesian capital market. This study collection technique uses primary data obtained from the survey questionnaire and secondary data which is market data, stock price movement data sourced from the Indonesia Stock Exchange, Indonesian Central Securities Depository, and Bank Indonesia, as well as empirical literature on behavior finance, investment decision, and interest in buying stock. The method used in this research is the survey questionnaire analysis with the SEM (statistical approach). The results of the analysis using SEM show that investor behavior influences the stock-buying interest, investor behavior, and the stock-buying interest influences investor decision-making. However, risk management does not influence investor-decision making. This occurs when the investigator's psychological capacity produces more decision information by decreasing all potential biases, allowing the best stock selection model to be selected. When the investigator's psychological capacity creates more decision information by reducing biases, the optimum stock selection model can be chosen.

• Animal Bioscience
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• v.37 no.7
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• pp.1185-1195
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• 2024

Objective: This meta-analysis aimed to evaluate the impact of wilted and unwilted silage on various parameters, such as nutrient content, fermentation quality, bacterial populations, and digestibility. Methods: Thirty-six studies from Scopus were included in the database and analyzed using a random effects model in OpenMEE software. The studies were grouped into two categories: wilting silage (experiment group) and non-wilting silage (control group). Publication bias was assessed using a fail-safe number. Results: The results showed that wilting before ensiling significantly increased the levels of dry matter, water-soluble carbohydrates, neutral detergent fiber, and acid detergent fiber, compared to non-wilting silage (p<0.05). However, wilting significantly decreased dry matter losses, lactic acid, acetic acid, butyric acid, and ammonia levels (p<0.05). The pH, crude protein, and ash contents remained unaffected by the wilting process. Additionally, the meta-analysis revealed no significant differences in bacterial populations, including lactic acid bacteria, yeast, and aerobic bacteria, or in vitro dry matter digestibility between the two groups (p>0.05). Conclusion: Wilting before ensiling significantly improved silage quality by increasing dry matter and water-soluble carbohydrates, as well as reducing dry matter losses, butyric acid, and ammonia. Importantly, wilting did not have a significant impact on pH, crude protein, or in vitro dry matter digestibility.

• Journal of the Korean Wood Science and Technology
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• v.43 no.2
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• pp.248-257
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• 2015

This research focused on the natural durability of twenty one lesser known tropical wood species planted in West Java, Indonesia against subterranean termite (Coptotermes curvignathus). It was observed that both heartwood and sapwood of Kiara payung (Filicium decipiens); heartwoods of Nangka (Arthocarpus heterophyllus), Mahoni (Swietenia macrophylla) and Simpur (Dillenia grandifolia); and sapwood of Bungur (Lagerstroemia speciosa) were rated as resistant (natural durability class II) according to Indonesian standard SNI 01.7207.2006 (BSN 2006). Both heartwood and sapwood of Salam (Syzigium polyanthum), Pasang (Lithocarpus sundaicus), Bisbul (Diospyros discolor), Rukam (Flacourtia rukam) and Trembesi (Samanea saman); heartwood of Puspa (Schima walichii), Bungur, Tanjung (Mimusops elangi) and Angsana (Pterocarpus indicus) were rated as moderately resistant (natural durability class III). Both heartwood and sapwood of Sungkai (Peronema canescens), Pine (Pinus merkusii), Mangium (Acacia mangium) and Afrika (Maesopsis eminii); sapwoods of Mahoni, Puspa and Tanjung were rated as poorly resistant (natural durability class IV). Both heartwood and sapwood of Agathis (Agathis dammara), Durian (Durio zibethinus), Ki sampang (Evodia latifolia) and Jabon (Anthocephalus cadamba); sapwoods of Nangka and Angsana were rated as very poorly resistant (natural durability class V). This reserach showed that woods with lower resistance against C. curvignathus attack (natural durability class IV and V) tend to have lower termite mortality values compared to woods with higher resistance against C. curvignathus attack (natural durability class II and III). Results of the study will provide some valuable information on termite resistance of twenty one lesser known tropical wood species planted in Indonesia.

• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.519-532
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• 2019

The objectives of this study were to evaluate the effects of shelling ratio and resin content on the properties of bamboo oriented strand board (BOSB) from betung (Dendrocalamus asper) and to determine the correlation between the results of dynamic and static bending tests. Strands were steam-treated at $126^{\circ}C$ for 1 h under 0.14 MPa pressure and followed by washing with 1% NaOH solution. Three-layer BOSB with the core layer perpendicular to the surface was formed with shelling ratios (face:core ratio) of 30:70; 40:60; 50:50; 60:40 and binded with 7% and 8% of phenol formaldehyde (PF) resin with the addition of 1% of wax. The evaluation of physical and mechanical properties of BOSB was conducted in accordance with the JIS A 5908:2003 standard and the results were compared with CSA 0437.0 standard for commercial OSB (Grade O-1). Non-destructive testing was conducted using Metriguard Model 239A Stress Wave Timer which has a wave propagation time from 1 to $9,999{\mu}s$ and a resolution of $1{\mu}s$. BOSB with 8% resin content showed better physical and mechanical properties than those with 7% resin content. The increase of the face layer ratio improved the strength of BOSB in parallel direction to the grain. The results suggested that shelling ratio of 50:50 could be used as a simple way to reduce PF resin requirements from 8% to 7% and to meet the requirements of CSA 0437.0 standard. The results of non-destructive and destructive tests showed a strong correlation, suggesting that non-destructive test can be used to estimate the bending properties of BOSB.

• NEWSLETTER 전기공업
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• no.92-28 s.71
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• pp.1-19
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• 1992

• 전기산업
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• v.3 no.4
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• pp.77-91
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• 1992

• Journal of the Korean Wood Science and Technology
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• v.46 no.6
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• pp.656-669
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• 2018

Tropical bamboo species, which have a very rapid growth rate, are considered as a promising non-timber forest product capable of exhibiting new functionality by carbonization technology. This study was conducted to compare the characteristics of carbonized bamboos from Andong (G. pseuudoarundinacea (Steudel) Widjaja), Hitam (G. atrovialacea), Tali (G. apus), Kuning (B. vulgaris Var. striata (Lodd. Ex Lindl)), and Ampel (B. vulgaris Scharad. ex Wendland), and Betung (D. asper). Each bamboo was carbonized at 200, 400, 600, 800, and $1,000^{\circ}C$, respectively, and their physical and anatomical characteristics were investigated. The result showed that the volume and weight of carbonized bamboo decreased with increasing carbonization temperature and showed the substantial changes of volume and weight between 200 and $400^{\circ}C$. The highest and the lowest density of carbonized samples were found in Ampel bamboo and Betung bamboo, respectively. The density of all carbonized bamboos tended to decrease after carbonization at 200 and $400^{\circ}C$ and relatively become constant afterwards. The carbonized bamboo prepared at 800 and $1,000^{\circ}C$ showed better refining degree. The results of the anatomical observation showed that the vascular diameter of carbonized bamboo decreased with increasing carbonization temperature, and the shrinkage in radial and tangential direction showed similar tendency. Statistical analysis showed that there was significant correlation between physical contraction and anatomical contraction. Based on the results of this study, comprehensive data about Indonesian bamboo charcoals could be obtained and it will be useful for future application studies.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.3
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• pp.465-479
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• 2020

Objective: This study performed a meta-analysis of published trials to determine the effects of zinc on the immune response and production performance of broilers. Methods: A database was built from published literature regarding the addition of zinc forms or doses and their relation to the immune response and production performance of broilers. Different doses or forms of zinc were identified in the database. The recorded parameters were related to the immune response and production performance. The database contained a total of 323 data points from 41 studies that met the criteria. Then, the data were processed for a meta-analysis using a mixed model methodology. The doses or different forms of zinc were considered fixed effects, different studies were treated as random effects, and p-values were used as the model statistics. Results: An increase in zinc dose increased (p<0.05) pancreas metallothionein (MT) and zinc concentrations in the plasma, tibia and meat, all in quadratic patterns, but linearly decreased (p<0.05) the heterophil/lymphocyte (H/L) ratio. Regarding the different zinc forms, both inorganic and organic zinc increased (p<0.05) the zinc concentrations in the plasma and tibia, the calcium and phosphorus contents in the tibia, and the antioxidant activity of superoxide dismutase in meat as compared to control. An increase in zinc dose increased average daily gain (ADG) and decreased feed conversion ratio (FCR) following a quadratic pattern (p<0.05). Inorganic and organic zinc decreased (p<0.05) FCR and H/L ratio than that of control, but these two forms were similar for these parameters. Conclusion: Zinc addition has a positive impact on immunity and broiler production. Zinc can suppress stress and inhibit the occurrence of lipid peroxidation in broilers, and it can also improve ADG, FCR, and the quality of broiler carcasses.