UMA - Open Access Journals (Universitas Medan Area)
Not a member yet
5228 research outputs found
Sort by
Pengaruh Pupuk Batu bara dan Kalium Terhadap Bunga dan Produksi Tanaman Kelapa Sawit (Elaeis guineensis Jacq.)
Get PDFThis study discusses the Effect of Coal and Potassium Fertilizers on the Flower and Production of Oil Palm Plants (Elaeis guineensis Jacq.). This study aimed to determine the interaction between coal fertilizer and potassium fertilizer, as well as the influence of each single factor, on the flower and production of oil palm plants, as well as the correlation between the observed variables. This study was conducted experimentally using a factorial Complete Random Design (RAL) with two aspects of treatment. The first aspect is the dosage of coal fertilizer with three levels: 0, 1, and 2 kg per plant per 6 months. The second aspect is the dosage of potassium fertilizer with 3 levels: 3, 4, and 5 kg per plant per 6 months. The results of the analysis showed that the combination of 1 kg of coal fertilizer and 5 kg of potassium fertilizer per plant was the best treatment. This treatment has been proven to accelerate the ripening time of fruit and significantly increase the production of oil palm plants
Pengaruh Keaktifan dan Komitmen Berorganisasi terhadap Kesiapan Kerja Mahasiswa Demisioner BEM KM UNISA
Get PDFArtikel ini bertujuan untuk menganalisis keaktifan berorganisasi dan komitmen berorganisasi terhadapkesiapan kerja mahasiswa sebagai demisioner BEM KM (Badan Eksekutif Mahasiswa KeluargaMahasiswa) Universitas ‘Aisyiyah Yogyakarta periode 2023/2024 yang beranggotakan 118 orang.Masalah difokuskan pada hubungan antara keaktifan dan komitmen berorganisasi dengan kesiapankerja. Guna mendekati masalah ini, menggunakan acuan teori dari Pool & Sewell (2007) yang membahasseputar keterlibatan organisasi dan kesiapan kerja. Data-data dikumpulkan melalui angket dengan skalaLikert yang telah diuji validitas dan reliabilitasnya, dan dianalisis secara kuantitatif korelasionalmenggunakan regresi linier berganda. Kajian ini menyimpulkan bahwa keaktifan berorganisasiberpengaruh signifikan terhadap kesiapan kerja, sedangkan komitmen berorganisasi tidak berpengaruhsignifikan berdasarkan hasil uji T dengan angka signifikan >0,05 yaitu 0,185. Namun, kedua variabelsecara bersama-sama berpengaruh terhadap kesiapan kerja dengan kontribusi 52,9% menurut hasil ujiR2. Hal ini menunjukkan semakin sering mahasiswa terlibat aktif dalam kegiatan organisasi, semakinbesar pula kesiapan kerja mereka untuk terjun ke dunia kerja. Dengan begitu, keaktifan berorganisasilebih berperan membentuk kesiapan kerja daripada tingkat komitmennya
Hubungan Body Image dengan Kepercayaan Diri pada Remaja Karang Taruna di Kecamatan Turi
Get PDFArtikel ini bertujuan untuk mengetahui hubungan antara body image dengan kepercayaan diri pada remaja Karang Taruna di Kecamatan Turi. Fokus utama dari penelitian ini adalah bagaimana persepsi remaja terhadap tubuhnya berpengaruh terhadap tingkat kepercayaan dirinya. Penelitian ini menggunakan metode kuantitatif korelasional, dengan teori body image menurut Thompson dan teori kepercayaan diri menurut Lauster sebagai acuan. Data dikumpulkan melalui penyebaran skala menggunakan Google Form kepada 127 responden, terdiri dari 52 laki-laki dan 75 perempuan, dengan mayoritas berusia 20 tahun. Analisis data menggunakan SPSS, data dianalisis melalui uji normalitas, linearitas, dan korelasi. Hasilnya menunjukkan adanya hubungan positif yang signifikan antara body image dan kepercayaan diri dengan nilai signifikansi 0,000 (<0,05) dan koefisien determinasi sebesar 0,642, yang berarti body image memberikan kontribusi 64,2% terhadap kepercayaan diri, sementara 35,8% dipengaruhi faktor lain. Kategorisasi data menunjukkan bahwa sebagian besar responden termasuk dalam kategori body image tinggi (92,1%) serta memiliki tingkat kepercayaan diri yang tergolong tinggi (44,9%). Temuan penelitian ini menunjukkan bahwa remaja yang memandang tubuhnya secara lebih positif cenderung menunjukkan tingkat kepercayaan diri yang lebih tinggi. Dengan demikian, body image menjadi salah satu faktor utama yang berperan dalam pembentukan kepercayaan diri pada remaja Karang Taruna di Kecamatan Turi
Komunikasi Lingkungan Masyarakat Destinasi Wisata Komunikasi Lingkungan Masyarakat di Kawasan Wisata Geopark Meratus Tahura Mandiangin
Get PDFThis study aims to analyze environmental communication practices in the context of managing the Meratus Geopark natural tourist destination, particularly in the Tahura Sultan Adam Mandiangin area, Banjar Regency, South Kalimantan. The approach used is a descriptive, qualitative one, employing Lasswell's communication model framework and Yenrizal's (2017) concept of environmental communication. The research findings indicate that environmental conservation communication practices remain hierarchical and top-down, with government institutions, particularly the Forestry Department, playing a dominant role in communication. Local communities have not been strategically involved in the process of message delivery or in the formulation of management policies for the area. The messages conveyed tend to be technocratic and have not integrated local cultural wisdom, while the media used include banners, the “bottle cage” trash bin innovation, and social media that have not been systematically coordinated. Feedback from tourists indicates a positive effect on conservation messages, but long-term effectiveness still depends on active local community participation and the strengthening of two-way communication. This study recommends the need to strengthen the role of local actors as communicators, integrate cultural values into environmental messages, and optimize digital media as part of a community-based conservation communication strategy
Hubungan Kebersyukuran dan Harga Diri dengan Kebahagiaan Anggota PGRI Aceh Barat
Get PDFPenelitian ini bertujuan untuk mengetahui hubungan variabel kebersyukuran dan harga diri dengan kebahagiaan anggota PGRI Aceh Barat. Populasi dalam penelitian ini sebanyak 1000 responden. Penelitian menggunakan pendekatan kuantitatif dan pengambilan sampel dalam penelitian ini dengan teknik purposive sampling berjumlah 100 orang. Instrumen yang digunakan adalah angket kebersyukuran, harga diri dengan kebahagian yang telah valid dan reliabel. Penelitian dianalisis dengan menggunakan uji Analisis Berganda. Hasil penelitian menunjukkan bahwa: (1) Ada hubungan yang positif dari kebersyukuran dengan kebahagiaan. Hal ini ditunjukkan Rx1-y = 0,317 dengan thitung = 3,568 > ttabel = 1,660 dan nilai signifikansi sebesar 0,001 < 0,05. (2) Ada hubungan yang positif dari harga diri dengan kebahagiaan anggota PGRI Aceh Barat. Hal ini ditunjukkan Rx2-y = 0,215 dengan thitung = 2,405 > ttabel = 1,660 dan nilai signifikansi sebesar 0,012 < 0,18. (3) Ada hubungan yang positif dari kebersyukuran dan harga diri dengan kebahagiaan anggota PGRI Aceh Barat. Dengan hasil Rx1.x2-y = 0,0389. Dan dari output diperoleh koefisien determinan (R2) sebesar 0,133 dengan nilai signifikansi 0,000 < 0,05
Bioenergy as a Key Driver of Energy Transition: A Case Study of Emission Reduction and Energy Security
Get PDFThe transition to renewable energy is an urgent step in addressing the global climate crisis and reducing dependence on fossil fuels, which have increased greenhouse gas emissions and exacerbated climate change. In this context, bioenergy emerges as an important solution because it not only helps reduce carbon emissions through cleaner and carbon-neutral combustion but also increases energy security by diversifying energy sources, especially through the utilization of organic biomass such as agricultural and forestry waste. This study aims to study more deeply about bioenergy as a key driver of energy transition through case studies related to emission reduction and energy security enhancement. Bioenergy plays an important role in the global energy transition because it is able to reduce dependence on fossil fuels and reduce carbon emissions. In addition to helping create a more resilient energy system by utilizing local biomass resources, bioenergy also supports the principle of a circular economy through the utilization of organic waste. Despite offering many benefits, bioenergy development faces challenges such as resource supply and production efficiency, but the opportunities to overcome these challenges remain large through technological innovation and supportive policies. Bioenergy plays an important role in the global energy transition towards clean energy by reducing carbon emissions and increasing energy security through the utilization of renewable biomass. Despite challenges in terms of policy, technology, and raw material supply, the great potential of bioenergy can be optimized through innovation and policy support to strengthen a more sustainable energy system. This study shows that bioenergy has great potential to reduce carbon emissions and increase energy security through the use of renewable biomass, but further development is needed to overcome efficiency and policy challenges to support the transition to a more sustainable energy system
Evaluation of Occupational Safety and Health Requirements in Confined Space at Turbine Maintenance PT. Sinergi Nusantara Gula PG Tjoekir
Get PDFConfined space is a high-risk workplace because it contains various sources of danger such as toxic gases, lack of oxygen, and fire risk. PT. Sinergi Gula Nusantara PG Tjoekir has implemented work procedures based on BINWASNAKER No. 113/DJPPK/XI/2006, but evaluation is needed to ensure compliance with the latest regulations, namely Permenaker No. 11 of 2023. The study aimed to evaluate the OSH Requirements in confined space turbine maintenance at PT. SGN PG Tjoekir is by Permenaker no. 11 of 2023, including confined space classification, access restrictions to enter confined spaces, entry permits, safe work procedures, equipment and equipment, and OSH confined space personnel. The type of research method used is qualitative descriptive, namely providing an overview of OSH requirements in a limited space for turbine maintenance. Then the data obtained is compared to its conformity with Permenaker No. 11 of 2023. The results of this study out of 17 conditions that must be met only 60% that have been met. The conditions that have not been met are the classification of confined space, testing and monitoring of hazardous atmospheric gases, labeling and energy isolation forms, supply respirators, testing, and monitoring equipment for hazardous atmospheric gases, penetrating voltage measuring instruments, and OSH confined space personnel. This study concludes that the OSH requirements in confined space turbine maintenance are in the category of lacking. The advice provided by the company can update the entry permit procedure and increase compliance with the latest regulation, namely Permenaker No. 11 of 2023 to improve work safety
Experimental Study on the Effect of a Cooling System on an Unmanned Surface Vehicle Prototype Using a Zenoah G32FC Engine
Get PDFThis study presents a performance test of the cooling system on an unmanned vessel prototype using a Zenoah G32FC engine. The purpose of this research is to evaluate the impact of the cooling system on engine temperature, radiator effectiveness, and vessel speed. The experiment was conducted using a platform supply vessel (PSV) prototype with a monohull design, measuring 120 cm in length and 35.15 cm in width. The Zenoah G32FC engine is a 2-stroke engine with a displacement of 31.8 cc, serving as the main propulsion unit for the prototype. Two types of coolant fluids were tested: water and radiator coolant. The results showed that the use of a radiator helped maintain engine temperature more effectively compared to operating without one, with an average test temperature of 64.3°C and a peak temperature of 71.6°C. The radiator coolant achieved the highest effectiveness, reaching 57.6%, with a heat transfer rate of 341 watts. Vessel speed remained relatively constant throughout all tests, indicating that the use of a radiator had minimal impact on speed, while still maintaining engine temperature within a safe range. Therefore, the use of a radiator is strongly recommended to optimize engine performance
Characteristics of Profile Pin Variation in HDPE Friction Stir Welding to Mechanical Properties of Materials
No full textFriction Stir Welding (FSW) is one of the Solid-State Welding processes, which joins materials below their melting point by continuously rubbing two workpieces together to generate heat. The FSW process heavily relies on the use of pin profiles, which play a crucial role in forming the weld joint, as they directly affect material flow in the weld zone and heat distribution during the welding process. This research aims to evaluate the mechanical properties of FSW joints made using different pin profile variations, in order to achieve high-quality welds. The study applies a descriptive statistical analysis approach, utilizing tensile testing, flexural testing, hardness testing, and macro photography. The material used in this research is High-Density Polyethylene (HDPE), with three types of pin profiles: triangular, threaded cylindrical, and grooved cylindrical. The welding parameters are kept constant: feed rate of 25 mm/min, spindle speed of 930 RPM, plunge depth of 3.84 mm, and tilt angle of 0°. The results show that the threaded pin profile produced the highest average values: hardness of 59.5 SHD, tensile strength of 11.5 MPa, and flexural strength of 22.4 MPa. In contrast, the grooved pin profile showed the lowest average values: hardness of 57.83 SHD, tensile strength of 4.99 MPa, and flexural strength of 4.22 MPa. The mechanical strength test results were influenced by weld defects observed through macro images. These weld defects significantly impacted the mechanical properties and demonstrated that pin profile geometry plays a vital role in heat generation through friction and in controlling the material flow dynamics, which directly determine the structural integrity and mechanical performance of the weld joint
Performance Analysis of Centrifugal Pump Head in Series and Parallel Circuit
Get PDFWhen the pump starts working and the fluid flow capacity is different from the pump capacity, an analysis is performed on the head value obtained from the pump whose value is insufficient to the required capacity. Analysis of the pump head capacity value is necessary to ensure that the pump can operate efficiently and according to system requirements. The method used to calculate the pump head value includes a theoretical approach and quantitative calculations. The pump head calculation is carried out by applying the Reynolds equation and other fluid mechanics principles, as well as considering factors such as flow velocity, pipe diameter, and fittings or supporting components used. The purpose of this analysis is to determine and calculate the optimal pump head value in a series or parallel arrangement so that the system can work under ideal conditions. The results of this study indicate that the pump head in a series arrangement is 3.9 m, while the Head value for a parallel arrangement is 2.2 m. The head loss value for the series arrangement is 0.000007108 or 71.08 {\times10}^{-6}, while the head loss value for the parallel arrangement is \ 0.000001197 m or 11.97 {\times10}^{-6}. Pumps with a series configuration are used to obtain higher pressures. Pumps with a parallel configuration are used to obtain larger flow rates