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The Effect of Lignin Extracted from Oil Palm Empty Fruit Bunches (OPEFB) as a Green Corrosion Inhibitor on ST 41 Steel in Sulfuric Acid Media
No full textThis research was conducted to investigate the effect of inhibitor concentration and immersion time on weight loss, corrosion rate, inhibition efficiency, and surface roughness variation of low-carbon steel ST 41. The study also aimed to evaluate the inhibition efficiency of lignin extracted from Oil Palm Empty Fruit Bunches (EFB) in reducing the corrosion rate of ST 41 steel and to analyze the morphological characteristics of the steel surface both with and without the inhibitor. The weight loss method was employed as the primary technique, as it is the simplest approach to determine the corrosion rate by comparing the initial weight of the specimen to its weight after immersion in the inhibitor solution. Morphological characterization and identification of the corrosion type were carried out through microscopic and cross-sectional observations. The results showed corrosion rate values of 31.6922 mpy, 24.8851 mpy, and 19.7146 mpy, corresponding to inhibition efficiencies of 34.56%, 53.93%, and 79.305% for the 3 g/L inhibitor concentration at immersion times of 1 hour, 3 hours, and 6 hours, respectively. Meanwhile, at a concentration of 7 g/L, the corrosion rates were 26.3358 mpy, 20.3842 mpy, and 15.9577 mpy, with inhibition efficiencies of 45.62%, 62.26%, and 83.24% for the same immersion durations. The adsorption behavior of the inhibitor on ST 41 steel was evaluated using the Langmuir adsorption isotherm model, which indicated that the dominant adsorption mechanism was physisorption.126 pagesSkripsi Sarjan
Effect of Lemongrass Essential Oil (Cymbopogon nardus) as an Alternative Solvent on Epoxy Resin Sealer Cleanliness of Root Canal Walls during Endodontic Retreatment (In Vitro)
No full textEndodontic retreatment requires the use of solvents to assist in the removal of
old obturation materials, including epoxy resin sealers that adhere strongly to root canal
walls. This study aimed to evaluate the effect of citronella essential oil (Cymbopogon
nardus) on the cleanliness of epoxy resin sealer on root canal walls during in
vitro endodontic retreatment. This in vitro experimental study with a post-test only
design used mandibular premolars divided into three groups: no solvent, orange oil,
and citronella essential oil. Root canal wall cleanliness was evaluated using a
stereomicroscope and analyzed quantitatively. The results demonstrated significant
differences in root canal wall cleanliness among the groups, with the orange oil group
showing the highest level of cleanliness, followed by the lemongrass essential oil
group, while the no-solvent group exhibited the lowest level. It can be concluded that
lemongrass essential oil contributes to improving the cleanliness of root canal walls
from epoxy resin sealer residues, although its effectiveness remains inferior to that of
orange oil.122 PagesSkripsi Sarjan
Experimental Study of Static Mechanical Properties and Crack Patterns of Concrete Reinforced with Palm Oil Fuel Ash and Fly Ash
No full textCement production significantly contributes to global carbon emissions, necessitating eco-friendly material innovations utilizing industrial waste. This study aims to analyze the effect of partial cement substitution using a combination of Fly Ash (FA) and Palm Oil Fuel Ash (POFA/ACS) on the static mechanical properties and crack pattern characteristics of Engineered Cementitious Composites (ECC) mortar. The experimental method involved varying Fly Ash levels (10% and 15%) and ACS levels (0%, 5%, 10%, and 15%) by weight of cement. Tests included slump flow, density, compressive strength, split tensile strength, microstructural analysis using Scanning Electron Microscope (SEM) and EDS, as well as crack pattern analysis following static testing. The results showed that all mixture variations exhibited good flowability with T500 spread times between 0.4 and 1.6 seconds. This material combination effectively improved density, where the M44 variation (15% FA + 15% ACS) recorded the lowest water absorption of 0.78%. The optimum composition was achieved in the M43 variation with a combination of 15% Fly Ash and 10% ACS. At 28 days, this variation yielded a maximum compressive strength of 49.56 MPa and a split tensile strength of 6.83 MPa, categorizing it as high-strength concrete. Microstructural analysis confirmed the formation of massive and dense Calcium Silicate Hydrate (C-S-H) gel due to pozzolanic reactions and the filler effect. Furthermore, the addition of ACS proved to alter the material's failure behavior from brittle columnar crack patterns in control specimens to more ductile shear crack patterns through a mechanical interlocking mechanism between particles.116 PagesSkripsi Sarjan
Small-Clawed Otters (Aonyx cinereus) Activities at the Rahmat Zoo and Park, Bengabing Village, Pegajahan, North Sumatera
No full textThis study aims to examine the activity patterns of small-clawed otters (Aonyx cinereus)
maintained at Rahmat Zoo and Park, Bengabing Village, Pegajahan, North Sumatra.
From a biological perspective, the study of daily activity provides important insights
into behavioral biology and supports conservation efforts by improving the
understanding of species adaptation under captive conditions. Observations are
conducted on a male and a female individual approximately one year old over a 14-day
period, from 08:00 to 16:00 WIB, using the focal animal sampling method with two
minute recording intervals. Activity data are classified into ten behavioral categories
and quantitatively analyzed by calculating the percentage frequency of each behavior,
which is then presented graphically. The results have shown that the dominant activities
of the male otter have been locomotion (36.32%) and resting (35.79%), whereas the
dominant activities of the female otters have been locomotion (34.72%) and resting
(36.85%). Other observed behaviors included vocalization, feeding, grooming, social
interaction, standing, alertness, elimination, territorial marking, begging, and mating,
all occurring at lower percentages. These findings demonstrated that the activities of
Aonyx cinereus in captivity have been largely dominated by locomotion and resting
behaviors and have been influenced by environmental factors and husbandry conditions.
This study has provided additional biological information to support management
practices and conservation strategies for small-clawed otters in conservation
institutions.70 PagesSkripsi Sarjan
Effect of Modified Orange Sweet Potato Flour (Beta-1 Variety) and Cinnamon Powder Concertration of Production of Cake Bolu Bhoi
No full textCUT PATHAN Effect of Modified Orange Sweet Potato Flour (Beta-1 Variety) and Cinnamon Powder Concentration on the Production of Cake Bhoi (supervision by MIMI NURMINAH as Head of the Supervisory Committee and ISMED SUHAIDI as Member of the Supervisory Committee).
The Beta-1 variety of orange sweet potato is rich in beta-carotene, a provitamin A that is beneficial to health. The orange sweet potatoes were processed into modified flour using annealing, acetic acid, bimo cf, and instant yeast to improve their physical and functional properties, and the best modification method was applied in the production of bolu bhoi. Bolu bhoi, a traditional Acehnese fish-shaped cake bhoi with a soft and sweet texture, was innovated by incorporating modified orange sweet potato flour to improve its nutritional value, along with cinnamon powder to enhance its flavor and aroma. Cinnamon contains cinnamaldehyde compounds with antioxidant properties. This study was aimed to determine the interaction effects of adding modified Beta-1 orange sweet potato flour and cinnamon powder concentration on the quality characteristics of cake bolu bhoi. The research employed a Completely Randomized Design (CRD) with two factors: modified orange sweet potato flour (T) (40%, 60%, 80%, 100%) and cinnamon powder concentration (B) (0%, 0,5%, 1%, 1,5%). The parameters analyzed included moisture content, ash content, fat, protein, carbohydrate, crude fiber, beta-carotene, antioxidant activity, color, texture, aroma, taste, and overall acceptance.
The results of the study showed that the addition of modified orange sweet potato flour of Beta-1 variety (T) had a highly significant effect (P<0,01) on moisture content, ash content, protein content, crude fiber content, color descriptives, flavor hedonic, texture descriptives, and overall acceptance hedonic, as well as a significant effect (P<0,05) on fat content, carbohydrate content, and aroma hedonic. The concentration of cinnamon powder (B) had a highly significant effect (P<0,01) on moisture content, ash content, color descriptives, aroma hedonic, flavor hedonic, and overall acceptance hedonic, and a significant effect (P<0,05) on fat content, carbohydrate content, protein content, crude fiber content, and texture descriptives. The best treatment, based on the De Garmo method, was T1B4, which was the treatment with the addition of 40% modified orange sweet potato flour of Beta-1 variety and 1,5% cinnamon powder concentration.146 PagesSkripsi Sarjan
Ownership Conflict Over Areas And Abandoned Land in Dusun I and V of Bandar Baru Village, Sibolangit District, Deli Serdang Regency
No full textLand has a very strategic position in the social, economic, and legal life of
Indonesian society, so that its management must be carried out in accordance with
the mandate of Article 33 paragraph (3) of the 1945 Constitution of the Republic of
Indonesia and Law Number 5 of 1960 concerning Basic Agrarian Regulations. This
study aims to determine and analyze how ownership conflicts and legal resolutions
occur in cases located in Hamlets I and V, Bandar Baru Village, Sibolangit District,
Deli Serdang Regency. The research method used is empirical juridical with a
qualitative approach. Data were obtained through library studies and field studies
in the form of structured interviews with the North Sumatra National Land Agency
(BPN), Legal Counsel and the Community of Hamlets I and V, Bandar Baru Village.
The results of this study indicate that the land ownership conflict has not yet been
resolved and is still in dispute, the conflict was also triggered by the indecisiveness
of the National Land Agency in providing legal certainty to the community
regarding the status of land in the area of Hamlet I and Hamlet V, Bandar Baru
Village, Sibolangit District, Deli Serdang Regency. This study also recommends
that the government needs to reorganize the legal status of land in a comprehensive,
transparent, and equitable manner to avoid the continuation of conflicts in the
future. The local government together with the land agency is expected to
immediately conduct an inventory and confirmation of the status of land rights by
involving the community as the party that has long controlled and utilized the land.126 PagesSkripsi Sarjan
Legal Protection for the Existence of the Pandumaan-Sipituhuta Indigenous Law Community Over the Customary Forest Post the Enforcement of Humbang Hasundutan Local Regulation No 3 of 2019 Concerning the Recognition and Protection of the Pandumaan-Sipituhuta Customary Law Community
No full textThe Pandumaan-Sipituhuta customary law community has historical, cultural, and economic ties to the Tombak Haminjon customary forest, which serves as their living space, source of livelihood, and their social identity. Changes in the legal framework following Constitutional Court Decision No. 35/PUU-X/2012, followed by the enactment of Humbahas Local Regulation No. 3 of 2019 and the customary forest decree, provide a strong basis for the recognition and protection of the customary rights of customary law community. However, the sustainability of legal protection for them still requires attention in order to keep pace with the times. This study aims to determine the legal protection of customary law community over customary forests in legislation, identify the mechanisms for recognizing and establishing customary law community and their customary forests, and examine the forms of legal protection for the Pandumaan–Sipituhuta customary law community before and after the enactment of Local Regulation No. 3 of 2019.
The method used was normative legal research with primary data support through interviews. The analysis was conducted qualitatively through a statute, conceptual, historical, and case approach..
The results of the study show that the legal protection of customary law cummunity over their forests has gained a strong normative basis, starting from the UUD 1945 to sectoral regulations such as the Forestry Law, followed by stages in accordance with ministerial regulations. The case study shows that before the Local Regulation, protection was still partial through the reservation of customary forests; while after the local regulation, recognition became more comprehensive, although there were still issues of inconsistency in the area covered by the 2020 customary forest decree, which was then revised in 2021. After this series of stagesthe customary law community and their rights to customary forests obtained legal protection guarantees, although the optimization of the implementation of the local regulation still needs to be strengthened.139 PagesSkripsi Sarjan
The Effect of Various Concentrations of BAP and NAA on In Vitro Shoot Multiplication of Red Barangan Banana (Musa acuminate colla).
No full textThe Barangan banana (Musa acuminate Colla) originates from North Sumatra and is distributed throughout Indonesia. The main problem in banana cultivation is the availability of seeds. Banana plants are generally propagated by suckers, making it difficult to obtain large numbers of seeds in a relatively short time. The resulting seeds are not uniform and are not free from pests and diseases. In vitro plant culture is a rapid method for plant propagation in an aseptic environment. This method can produce high-quality plants with characteristics consistent with the parent plant and free from pests and diseases. This study aims to determine the effect of various concentrations of BAP and NAA in MS medium on shoot multiplication of red Barangan banana (Musa acuminate colla). This research was conducted at the Biotechnology Laboratory, Faculty of Agriculture, University of North Sumatra, from June to October 2025. A completely randomized design (CRD) was used with two factors. The first factor was the concentration of benzyl aminopurine (BAP): B0 (0 ppm), B1 (4 ppm), and B2 (6 ppm). The second factor was the concentration of naphthalene acetic acid (NAA): N0 (0 ppm), N1 (1 ppm), and N2 (2 ppm). Parameters observed in this study included the percentage of live explants (%), age at shoot emergence, number of shoots, shoot length, number of roots, root length, and number of leaves. The results showed that the BAP concentration significantly affected the age at shoot emergence, number of shoots, and number of leaves. The interaction between BAP and NAA significantly affected shoot length, number of roots, and root length.68 pagesSkripsi Sarjan
Implementation Of The IndoBERT Method For Emotion Analysis On User Reviews Of The M-Paspor Application
No full textThe M-Paspor application serves as an essential digital platform for managing passport services online, making user reviews on the Google Play Store a valuable source for understanding public experiences with the system. These reviews contain various emotional expressions, ranging from appreciation to technical complaints, which require an artificial intelligence approach for effective analysis. This study employs the IndoBERT model due to its strong capability in interpreting Indonesian linguistic context through Deep learning methods. The research process includes collecting 2,996 user reviews, performing text cleaning and normalization, assigning initial sentiment labels using the Inset lexicon followed by manual verification, splitting the dataset, and fine-tuning IndoBERT with a maximum input length of 63 tokens. Evaluation on 446 test samples shows that IndoBERT achieves an accuracy of 86% and a macro F1-score of 0.61, demonstrating strong performance on positive and negative sentiment classes. This study concludes that IndoBERT is effective in identifying user emotions, although the neutral class remains challenging due to its limited representation and more ambiguous linguistic patterns. The findings also indicate inconsistencies between star ratings and textual sentiment in several reviews, suggesting that text-based analysis provides a more representative understanding of user perceptions toward the M-Paspor service.73 PagesSkripsi Sarjan
Morphological Characterization in the Vegetative and Generative Phases of Rainbow Corn (Zea Mays L.) F4 generation population of open polination 3 of parents
No full textThis study aims to determine the characteristics of F4 generation corn
plants resulting from F3 free crossing, which are expected to be useful as a genetic
source for forming a new base population as selection material for developing
desired varieties. The study was conducted at Jalan Pasar 1 No. 296 Tanjung Sari,
Medan Selayang District, from March to June 2025 using descriptive statistical
analysis methods. The corn seeds used were pre-mixed seeds taken at random. The
parameters observed were plant height, stem diameter, number of leaves, male
flowering age, female flowering age, difference in male and female flowering age,
male flower color, female flower color, stem color, and stem hair color. The results
showed that the phenotypic variance values had diverse or broad criteria for the
characteristics of plant height, number of leaves, stem diameter, male flowering
age, and female flowering age. Qualitative observations of male flower color and
variations between observations were green and greenish purple, while female
flowers varied in color between green and brown. Qualitative observation
characteristics for stem color showed color variations, namely green and purple.
In qualitative observations of hair color, there were no variations because there was
only one color, namely white.62 PagesSkripsi Sarjan