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Diversity and Potential of Cellulolytic Bacteria and Fungi From The Gut of Oryctes rhinoceros L.
No full textThe gut of insects is the natural habitat of various microbes that have the ability to
degrade cellulose, which is the main component of plant walls. Oryctes rhinoceros L.,
is one of the pests in oil palm and is thought to have potential cellulolytic bacteria and
fungi in the digestive tract that have not been widely explored. This study aims to
uncover the diversity and potential of cellulolytic bacteria and fungi from the gut of
O. rhinoceros L. as a new source of enzymes. Isolation of bacteria and fungi is
conducted by the spread plate method using the medium of Nutrient Agar (NA) for
bacteria and Potato Dextrose Agar (PDA) for fungi. Screening of cellulolytic activity
was conducted using the selective medium of Carboxymethyl Cellulose (CMC) 1%.
Identification of isolates could potentially be conducted based on morphological
characters as well as molecular analysis of the 16S rRNA gene for bacteria and ITSrDNA for fungi. The cellulase enzyme was purified using gel filtration
chromatography and ion exchange chromatography using DEAE-cellulose. Enzyme
characterization includes molecular weight analysis with SDS-PAGE, measurement of
specific activity, pH, optimal temperature, and the influence of metal ions on enzyme
activity. A total of 42 bacterial and fungal isolates were successfully isolated from the
digestive tract of instar III larvae and O. rhinoceros L. beetles, consisting of 19
bacterial isolates and 23 fungal isolates. Based on the Shannon and Simpson index, it
shows that the diversity of bacteria and fungi in the gut of O. rhinoceros L. is high
with a Shannon index value of 1.768-1.979 and a Simpson index of 0.826-0.847. Four
isolates showing the highest cellulolytic activity index were identified as Bacillus
tequilensis B01L (1.28) and Fusarium oxysporum F05L (0.90) isolated from the
gastrointestinal tract of instar III larvae. Bacillus cereus B19L (2.50) and Aspergillus
niger KOr15J (1.93) from the digestive tract of beetles. Pure cellulase yields a
molecular weight of 52.23 kDa for bacterial enzymes and 72.61 kDa for fungal
enzymes obtained from ion exchange chromatography. The highest specific activity
was shown by the cellulase enzyme of B. cereus B19L at 9.221 U/mg, followed by B.
tequilensis B01L (8.529 U/mg), F. oxysporum F05L (8.077 U/mg), and A. niger
KOr15J (4.242 U/mg). The cellulase activity of the bacteria shows optimum at pH 6–
7 and pH 5–6 for fungi, an optimum temperature of 30°C to 60°C. Ca²⁺ ions increase
the activity of cellulase enzymes from bacteria, while Fe²⁺ ions increase cellulase
activity from fungi. This study shows that bacteria and fungi from the digestive tract
of O. rhinoceros L. have high diversity and great potential in the stable and efficient
production of cellulase enzymes. This potential also shows the alpha ability to degrade
filterpaper, making it very prospective for the bioconversion of cellulose waste.152 PagesDisertasi Dokto
Analysis of the Effect of Wage System on Productivity of Oil Palm Harvesting Employees at PT. Langkat Nusantara Kepong
No full textSolihinta Aulia Pratama (180304097) with the thesis title is “Analysis of the Effect of Wage System on Productivity of Oil Palm Harvesting Employees at PT. Langkat Nusantara Kepong". Guided by Bapak. Ir.M. Jufri, M.Si and Ibu Dr. Ir. Salmiah, MS. The purpose of this study was to analyze the effect of salaries, premiums and bonuses on the work productivity of oil palm harvesters. The analytical method used is multiple linear regression analysis with SPSS 17.0. The method of sampling uses the census method and the samples of this study are 33 employees of oil palm harvesters at PT. Langkat Nusantara Kepong. Determination of the study area done purposively. The results of the study concluded that simultaneously the salary, premium and bonus factors had a significant effect on the productivity of oil palm harvesters at PT. Langkat Nusantara Kepong. Partially, the salary and bonus factors have no significant effect on the productivity of oil palm harvesters, while the premium factor significantly affects the productivity of oil palm harvesters at PT. Langkat Nusantara Kepong.58 PagesSkripsi Sarjan
Hardness of Scaffolds Based on Nano-Hydroxyapatite from Nile Tilapia Fish Scales and Commercial Gelatin Using the Porogen Leaching Method with Different Weight Concentration Ratios
No full textAlveolar bone defects caused by periodontitis require a bone tissue engineering approach using scaffolds with adequate mechanical and biological properties. Nano-hydroxyapatite is a biomaterial that resembles natural bone minerals and has the potential to be used as a scaffold material, while tilapia fish scales (Oreochromis niloticus), as fisheries waste, can be utilized as a natural source of hydroxyapatite. This study is an experimental laboratory study aimed at analyzing the hardness of scaffolds based on nano-hydroxyapatite from tilapia fish scales and commercial gelatin using the porogen leaching method at weight concentration ratios of 20:10, 30:15, and 40:20. This study used scaffolds as samples with a diameter of 6.5 mm and a thickness of 10.8 mm made from nano-hydroxyapatite synthesized from tilapia fish scales using the calcination and alkaline heat treatment methods, followed by ball milling until the material reached nano size (<100 nm). A total of 30 samples were prepared and divided into 3 groups (n=10) according to the weight ratio of hydroxyapatite and gelatin, namely 20:10 (I), 30:15 (II), and 40:20 (III). The scaffolds were fabricated using the porogen leaching method and calcined at a temperature of 800°C. Hardness testing was conducted using a Vickers Hardness Tester. The results showed the highest hardness value in group III (4.31 ± 0.06 VHN), followed by group II (3.03 ± 0.01 VHN), and the lowest in group I (1.13 ± 0.01 VHN). Statistical analysis using One-Way ANOVA showed significant differences in scaffold hardness values at various weight concentration ratios among all treatment groups (p<0.05). It can be concluded that the concentration of nano-hydroxyapatite increases the hardness value of the scaffold, with a higher percentage of nano-hydroxyapatite than gelatin. Scaffolds based on nano-hydroxyapatite from tilapia fish scales and commercial gelatin show potential as scaffold materials for bone regeneration applications.104 PagesSkripsi Sarjan
Design of a 4-Meter-High Cantilever Retaining Wall Alternative 1 for Landslide Mitigation Using Analytical Methods and PLAXIS 2D (Case Study: Perkebunan Nusantara, North Sumatra)
No full textLandslides frequently occur in Indonesia due to various factors, including
geological and topographical conditions, high rainfall, volcanic activity, and soil
types prone to failure. Landslides can damage infrastructure and cause economic
losses, as in the case at the palm oil mill owned by Perkebunan Nusantara. A slope
failure on one side of the loading ramp disrupted the production process, requiring
a geotechnical analysis to determine an appropriate reinforcement alternative so
that the ramp could operate again.This study aims to analyze slope stability under
existing conditions and after reinforcement. The analysis was conducted using two
methods: manual calculation and numerical modeling with PLAXIS 2D 2024.2
software. The results from both methods were compared to evaluate the
effectiveness of the planned reinforcement.Based on the analysis, the safety factor
of the original slope was found to be below the required standard (SF < 1.5),
indicating that the slope was vulnerable to landslides. After reinforcement with a
cantilever retaining wall based on the proposed design, the safety factor increased
to 1.506 under static conditions and 1.160 under seismic loading. Both values meet
the stability criteria.Therefore, the cantilever retaining wall proved effective in
improving slope stability and reducing landslide potential. This solution is expected
to support smooth operations at the loading ramp and serve as an alternative
method in slope reinforcement planning as well as a reference for landslide
mitigation using retaining walls.152 PagesSkripsi Sarjan
The Effect of Government Expenditure in the Education and Health Sectors on the Human Development Index (HDI) in Indonesia: An Ardl Approach
No full textThis study aims to analyze the effect of government expenditure in the education and health sectors on the Human Development Index (HDI) in Indonesia by incorporating control variables, namely population size, open unemployment rate, and gender ratio. The analytical method employed is the Autoregressive Distributed Lag (ARDL) model using EViews 10 software. The data used in this study are time series data covering the period 1990-2023, obtained from the Central Statistics Agency (BPS) and the Ministry of Finance of the Republic of Indonesia. The results indicate that in the short run, education expenditure has a positive and significant effect on HDI, while health expenditure and population size have a negative and significant effect. The open unemployment rate and sex ratio have a negative but insignificant effect on HDI. In the long run, education expenditure has a positive but insignificant effect, while health expenditure, population size, and sex ratio have a negative and significant effect. Meanwhile, the open unemployment rate has a positive but insignificant effect on HDI in Indonesia. Overall, the findings emphasize that improvements in HDI in Indonesia depend not only on the magnitude of government expenditure but also on the effectiveness of budget management, population growth control, employment expansion, and the enhancement of gender equality to achieve sustainable human development.144 PagesTesis Magiste
Implementation of an Iot-Based Smart Security System Using Esp32-Cam, Pir, And Esp32 With Dual Mode, Powered By Solar Energy
No full textThe use of conventional CCTV systems is considered inefficient for security applications due to manual monitoring requirements, the need for additional guards, the absence of real-time alerts, and strong dependence on grid electricity. These limitations highlight the need for a more capable and efficient visual-based security system. This study designs and implements an intelligent security device integrating an ESP32 microcontroller, an ESP32-CAM, a PIR sensor, and a servo mechanism powered by a 100 Wp Surya panel. System performance was quantitatively evaluated using detection accuracy, latency, and power consumption parameters. Experimental results demonstrate excellent performance, achieving 100% detection accuracy across 10 test cycles in both manual and automatic modes, with consistent system latency between 2.3–2.5 seconds and stable video streaming at 14–15 fps. The dual-mode operation eliminates synchronization conflicts and priority issues reported in previous studies, while maintaining zero streaming disruptions and 100% servo motor positioning precision with an angular error of ±1°. Power consumption was optimized to 1.9 W, supported by a Surya-battery system providing 403.56 Wh of backup energy, enabling continuous 24-hour security operation even under suboptimal lighting conditions. This prototype validates its practical applicability for remote industrial security monitoring in off-grid locations, offering a sustainable and cost-effective solution for agricultural, construction, and residential environments.108 PagesSkripsi Sarjan
Structural Design of a Cantilever-Type Retaining Wall with 60 cm Diameter Bored Pile Reinforcement as an Alternative for Landslide Mitigation Using the PLAXIS 2D Program (Case Study: Perkebunan Nusantara, North Sumatra)
No full textLandslides are one of the most frequent geotechnical disasters in Indonesia,
often causing significant losses in terms of infrastructure and economy. They are
triggered by various factors such as geological conditions, steep topography, high
rainfall, seismic activity, and poor soil stability. One such case occurred at the
loading ramp area of a palm oil mill, which disrupted the production process and
required geotechnical analysis to determine the appropriate slope reinforcement.
This study focuses on the design of a cantilever retaining wall structure combined
with bored pile reinforcement as an alternative solution. The analysis was
conducted using two approaches: manual calculations based on slope stability
theory and numerical simulations with PLAXIS 2D 2024.2, and the results of both
methods were compared to evaluate the effectiveness of the proposed design. The
results show that the existing slope has a safety factor (SF) below the required
standard (SF < 1.5), indicating a critical and failure-prone condition. However, after
the reinforcement was applied, the safety factor increased to 1.506 under static
conditions and 1.106 under seismic loading, both of which met the minimum slope
stability requirements. Therefore, it can be concluded that the use of a cantilever
retaining wall with bored pile reinforcement is effective in improving slope stability
and preventing potential recurrent landslides, while also ensuring smooth
operational performance in the loading ramp area. Moreover, this approach can
serve as a design reference for similar geotechnical problems in other locations.154 PagesSkripsi Sarjan
Pre-Design of the Plant for the Manufacture of N-Butyl Acetate from Acetic Acid and Butanol Using The Reactive Distillation and Pervaporation Membrane Separation Method with a Production Capacity of 10,000 Tons/Year
No full textN-Butyl Acetate is a compound that can be obtained from the esterification process
of acetate compounds and butyl alcohol compounds either in batch or continuously.
N-Butyl Acetate is widely used as a solvent in various industries such as the paint
and coating industry such as nail polish and printing ink, the cosmetics industry
such as perfume, the food and beverage industry such as synthetic flavors, the
textile industry, plastics and artificial leather, and the pharmaceutical industry. The
pre-design of the n-butyl acetate manufacturing plant from acetic acid and butanol
is designed with a production capacity of 10,000 tons/year and operates for 330
days a year. The factory location is planned to be built in the Java Integrated
Industrial and Port Estate (JIIPE) Gresik Industrial area, which is located on Jl. Kig
Raya, Manyar District, Gresik Regency, East Java, Indonesia with a factory area of
15,268 m2. The workforce required is 160 people with the factory business entity
form being a Limited Liability Company (PT) with a line and staff organizational
structure. The results of the economic evaluation show that the investment capital
(CI) value is Rp. 541,359,582,913.90, the total production cost is Rp.
396,107,190,620.20 and sales profit is Rp. 534,815,453,365.90 with a net profit of
Rp. 108,693,395,737. This factory is projected to reach the break-even point (BEP)
at 53.425% capacity with a return on investment (POT) of 5 years and 2 months.
Based on the results of the economic analysis, the factory design is considered
feasible to be established.502 PagesSkripsi Sarjan
Synthesis of Coffee Parchment-Dolomite-Calcium Oxide Based Pellet Catalysts for Biomass Waste Gasification
No full textIndonesia memiliki potensi biomassa yang melimpah, salah satunya limbah kulit tanduk kopi (KT) yang belum dimanfaatkan secara optimal. Limbah ini berpotensi digunakan sebagai bahan baku dalam teknologi gasifikasi untuk menghasilkan gas sintetis (syngas) yang ramah lingkungan. Penelitian ini bertujuan untuk mengembangkan katalis berbasis dolomit dan residu pembakaran KT serta mengevaluasi pengaruhnya terhadap efisiensi proses dan kualitas produk gas dalam proses gasifikasi biomassa. Katalis disintesis menggunakan residu pembakaran KT yang dikombinasikan dengan dolomit dan kalsium oksida dalam berbagai komposisi. Residu KT diperoleh melalui pembakaran terkontrol pada temperatur 500 ℃, 600 ℃, dan 700 ℃ menggunakan furnace, dan pembakaran secara manual (tanpa kontrol temperatur). Pembakaran KT tanpa kontrol temperatur menghasilkan material dengan kandungan mineral utama seperti K dan Ca yang lebih tinggi, selanjutnya disebut CR (combustion residue). Katalis dibuat dengan rasio CR, dolomit, dan kalsium oksida 1:1:1; 2:1:1; 1:2:1; 1:1:2; 1:0:0; 0:1:0; 0:0:1 (b/b). Berdasarkan uji daya serap iod, rasio 1:2:1 menunjukkan nilai tertinggi yaitu 182,74 mg/g. Katalis ini kemudian dicetak berbentuk pellet untuk memudahkan aplikasi pada reaktor gasifikasi tipe downdraft. Gasifikasi menggunakan limbah biomassa KT dan menambahkan 10%, 20%, 30%, dan 40% (b/b) katalis pellet dan temperatur proses 500 ℃, 600 ℃, dan 700 ℃. Hasil penelitian menunjukkan bahwa gasifikasi limbah KT menggunakan 20% katalis pellet pada temperatur 600 ℃, menghasilkan syngas yang memiliki kandungan H₂ mencapai 36,02% dengan rasio H₂/CO sebesar 1,18, dan nilai kalor (lower heating value, LHV) 7,63 MJ/m³. Penelitian ini membuktikan bahwa katalis berbasis dolomit dan residu pembakaran KT efektif dalam meningkatkan performa gasifikasi biomassa, baik dari segi efisiensi maupun kualitas produk gas. Selain itu, inovasi ini memberikan solusi dalam pengelolaan limbah agroindustri kopi dan mendukung penerapan teknologi produksi energi bersih. Penelitian lebih lanjut disarankan untuk mengoptimalkan variabel proses gasifikasi dan mengevaluasi potensi regenerasi katalis untuk penggunaan berulang.Disertasi Dokto
Analysis of the Leadership of the Head of the Inpatient Ward in Improving Patient Safety Culture at Kabanjahe Regional General Hospital in 2025
No full textEstablishing a culture of patient safety is essential in delivering healthcare services. A strong patient safety culture can reduce adverse events and enhance hospital accountability toward patients and the community. Therefore, hospitals must prioritize patient safety and build systems that support its continuous improvement. Effective leadership is crucial in implementing patient safety culture. One of the patient safety standards emphasizes the role of leadership in fostering such a culture. Strong leadership can enhance safety culture through competency development and active engagement. This study employed a qualitative approach using phenomenological methods to understand the meaning behind participants' experiences. Interviews with the heads of inpatient units at Kabanjahe Regional Hospital revealed that they hold strategic roles as frontliners in implementing patient safety culture. These leaders employ well-planned and measurable operational strategies to build a robust safety culture. The findings indicate that a participatory leadership approach characterized by effective communication, staff mentoring, and exemplary behaviour is key to success. To further improve the patient safety culture at Kabanjahe Hospital, it is recommended to strengthen the organizational structure by establishing a dedicated team focusing on patient safety and creating formal frameworks to support implementation.109 PagesSkripsi Sarjan