bluuebunny/crossref_metadata_2025_split huggingface dataset:
PERBEDAAN HASIL BELAJAR SISWA DENGAN MENGGUNAKAN MODEL PELATIHAN BERBASIS METODE PRAKTIKUM
Authors: Maurita Siska 
Published: June 2019

Penelitian ini bertujuan untuk mengetahui hasil belajar siswa yang diajar dengan menggunakan model pelatihan berbasis metode praktikum di SMAN 1 Meulaboh T. P 2016/ 2017. Metode penelitian yang digunakan adalah Eksperimen, dan desain penelitian adalah Pretest-Posttest Control Group Design. Populasi penelitian adalah siswa kelas X SMAN 1 Meulaboh yang terdiri dari enam kelas setiap kelas berjumlah 40 siswa, dan kelompok sampel ditentukan dengan teknik random sampling sehingga diperoleh dua kelas yang menjadi sampel penelitian. Instrumen yang digunakan adalah tes bentuk pilihan berganda yang telah ditentukan validitas dan reliabilitasnya sebanyak 20 soal.Kemudian pada sampel diberikan perlakuan yang berbeda, kelas eksperimen menggunakan model pelatihan berbasis metode praktikum dan kelas kontrol menggunakan pembelajaran konvensional. Pada awal pembelajaran siswa diberikan pretes dengan hasil rata – rata kelas eksperimen 28,4 dan kelas kontrol 27,8. Setelah pembelajaran selesai diperoleh postes dengan hasil rata – rata kelas eksperimen 81,5 dan kelas kontrol 69,1. Dengan demikian diperoleh kesimpulan bahwa ada perbedaan hasil belajar antara kelas eksperimen yang menggunakan model pelatihan berbasis metode praktikum dan kelas kontrol yang menggunakan pembelajaran konvensional selama kegiatan belajar mengajar di SMAN 1 Meulaboh T.P 2016 / 2017Kata Kunci: model pelatihan, metode praktikum.
Evaluasi Hate Rate dan Efisiensi suatu PLTU dengan menggunakan Batubara yang Berbeda dari Spesifikasi Design
Authors: Aziz Amiral , Hasan Andi Rinaldi 
Published: June 2019

Tulisan ini menampilkan beberapa hasil penelitian yang dilakukan untuk mengevaluasi hate rate dan efisiensi PLTU batubara berkapasitas 300 MW yang menggunakan spesifikasi batubara yang berbeda dari spesifikasi rancangan setelah beroprasi sekitar dua tahun. Hasil dari penelitian ini memperlihatkan bahwa efisiensi boiler (HHV basis) pada pengujian aktual 100% LRC mengalami penurunan sebesar 3,25% dan pada pengujian dengan komposisi 50% LRC dan 50% MRC mengalami mengalami penurunan sebesar 2,91% dibandingkan dengan hasil komisioning. Kehilngan panas karena gas buang kering, kandungan air dalam bahan bakar dan pembakaran hidrogen memberikan kontrobusi yang besar terhadap penurunan efisiensi boiler dibandingkan dengan hasil komisioning. Pada beban maksimun, turbine hate rate pada 2 (dua) pengujian aktual 100% LRC masing-masing sebesar 1.994, 67 kcal/kWh dan 1.918,55 kcal/kWh, sedangkan pada pengujian dengan komposisi 50% LRC dan 50% MRC turbine hate rate adalah 1.977,52 kcal/kWh. Nilai tersebut lebih rendah 4,47% dan 3,78% untuk pengujian aktual 100% LRC dan lebih rendah 3,45% untuk pengujian 50% LRC dan 50% MRC dibandingkan dengan hasil komisioning. Gross plant hate rate (HHV basis) pada 2 (dua) pengujian 100% LRC masing-masing 2.320,60 kcal/kg dan 2.293,63% kcal/kg, sedangkan pengujian 50% LRC dan 50% MRC gross plant hate rate (HHV basis) adalah 2.290,75 kcal/kg. Nilai ini lebih besar masing-masing sebesar 3,28%, 2,08% dan 1,95% dibandinkan hasil komisioning (2.246.84 kcal/kWh)
Pengaruh Perubahan Mikrostruktur Terhadap Perubahan Kekerasan Radiant Tube Yang Telah Beroperasi Sejak 2003
Authors: Sari Laili Novita 
Published: June 2019

Abstract B2TKS - Sub- Analysis of Damage and residual life has done Remaining Life Assessment to the radiant tube on oil and gas companies from 2003 - 2016. In determining the RLA, it was used graph of the Era Technology where the determination is based on the microstructural changes while there are no literature or research which shows the hardness changing of material ASTM A 213 T5 which occurs during the aging process. Therefore it need to make formulation about the changes of spheriodizationto the chages of hardness of radiant tube material ASTM A 213 T5. By knowing a reasonable decrease in hardness to spheriodization, it was expected to detect the abnormal condition or damage earlier. Based on the examination of metallographic and hardness testing ,is was known that the reduction of hardness occur in proportion to the increase ofsperiodization percentage. In spheriodzation changing of Classification A, B, C the decrease of hardness below 0.7 HB / HB0 while classification D until the next classification,reduction of hardness above 0,7HB / HB0. B2TKS – Sub Bidang Analisa Kerusakan dan umur sisa telah melakukan Remaining Life Assesment pada radiant tube pada perusahaan minyak dan gas bumi dari tahun 2003 – 2016. Dalam penentuan RLAdigunakan grafik dari Era Teknologi dimana penentuannya berdasarkan perubahan struktur mikro sedangkan untuk perubahan kekerasan material belum ada literatur atau penelitianyang menunjukkan tentang perubahan kekerasan pada material ASTM A 213 T5yang terjadi selama proses penuaan. Karena itu dilakukan perumusanperubahan kekerasan terhadap speriodisasi pada tube radiant material ASTM A 213 T5. Dengan mengetahui penurunan kekerasan yang wajar terhadap speriodisasi diharapkan akan mempermudah pendeteksian awal kondisi abnornal atau kerusakan. Berdasarkan pengamatan metalografi dan uji kekerasan diketahui bahwa penurunan kekerasan terjadi secara proporsional dengan peningkatan prosentase spriodisasi. Klasifikasi A, B, C penurunan kekerasan dibawah 0,7 HB/HB0 sedangkan klasifikasi D sampai berikutnya penurunan kekerasan diatas 0,7HB/HB0. Keywords: Hardness, radiant tube, in situ metallography, ASTM A 213 T5
ANALISIS KERUSAKAN GERBONG DATAR “PPCW”42 TON AKIBAT BEBAN OPERASI
Authors: . Anwar , Gozali M. 
Published: June 2019

Several units of PPCW wagons capacity of 42 ton are used for the cement transportation, cracked on the under frame structures. To determine the cause of the cracks, the investigation was conducted by measuring the stress that occurs when the wagons operation.Results of the investigations are the mean stresses and amplitude stresses measured in real-time in the various road conditions, and then be analyzed using fatigue limit diagram approach to get fatigue strength of the wagon structure. The analysis result shows that the stresses at several points of the wagon structure under the operational loads are in the critical area or is above the fatigue limit diagram. This is the cause of the failure of the under frame of the PPCW wagon structure.AbstrakBeberapa unit gerbong PPCW kapasitas 42 ton yang digunakan untuk pengangkutan semen, mengalami retak pada bagian rangka bawah. Untuk menegetahui penyebab terjadinya retak tersebut, dilakukan penelitian dengan cara mengukur tegangan yang terjadi pada saat gerbong beroperasi.Hasil penelitian berupa besaran tegangan rata-rata dan tegangan amplitudo yang diukur secara real-time pada berbagai kondisi jalan, dianalisis dengan menggunakan pendekatan diagram batas lelah. Hasil analisis menunjukkan bahwa tegangan pada beberapa titik berada pada daerah kritis atau diagram garis batas lelah. Hal ini merupakan penyebab terjadinya kerusakan struktur rangka bawah gerbong PPCW.Keywords : PPCW wagon, stresses, fatigue limit diagram.
PENIPISAN PIPA KETEL AKIBAT ELEMEN KOROSIF AIR
Authors: Nusa M. N. Setia , . Hernadi 
Published: June 2019

Inspection and testing is done to determine the metallurgical phenomena that occur on the boiler pipes that have been operating several years continuously at a temperature of 560 ° C. The study is also intended to determine the operational feasibility of the pipeline and to avoid undetected damage.Investigation of these pipes is also carried out in the laboratory with micro-structure analysis method, inspection crust, tensile test, bending test, hardness and thickness test.From the analysis of the microstructure, boiler pipes are in condition ferrite pearlite spheroidization with a crust that is thick and contains graphite. In addition, The pipes are attacked by uniform and pitting corrosion. The results of tensile and bending tests are still normal (standard). The hardness test results show significant values compared to the standard, as well as the thickness of the pipe thinning as a result of the corrosion process.AbstrakInspeksi dan pengujian dilakukan untuk mengetahui fenomena metalurgis yang terjadi terhadap pipa ketel uap yang sudah beroperasi beberapa tahun secara terus menerus pada suhu 560°C. Penelitian juga dimaksudkan untuk mengetahui kelayakan operasional pipa tersebut dan untuk menghindari terjadinya kerusakan yang tidak terdeteksiInvestigasi pipa-pipa tersebut juga dilakukan di laboratorium dengan metode analisa struktur mikro, pemeriksaan kerak, uji tarik, uji bending, uji kekerasan dan ketebalan.Dari analisa struktur mikro, pipa ketel berada pada kondisi ferrit spheroidisasi perlit dengan lapisan kerak yang cukup tebal serta mengandung grafit. Selain itu juga terjadi serangan korosi merata dan korosi sumuran. Hasil uji tarik dan hasil uji bengkok masih normal (memenuhi standar). Hasil uji kekerasan terjadi penurunan nilai yang signifikan dibanding standar, demikian juga pada ketebalan pipa terjadi penipisan akibat dari adanya proses korosi.Keywords: Boiler pipe, spheroidization, corrosion, thinning.
PENGARUH PERSENTASE REDUKSI WARM ROLLING TERHADAP SIFAT MEKANIK PADUAN Cu-Zn 70/30
Authors: Ridhowati Ayu Rizeki , Febriyanti Eka , Riastuti Rini 
Published: June 2019

Warm rolling is one of the thermomechanical method has several advantages such as produces high mechanical properties, but does not decrease % elongation and toughness value because partial recrystallization phenomenon that produces micron-sized new grain. This paper reports the results of an investigation carried out on the effects of holding time annealing to mechanical properties Cu-Zn 70/30 alloy. These alloy after homogenization process and quenched in the air then heated to temperature of 300°C, later the heated copper samples are warm rolled at 25%, 30%, and 35% reduction, after that heated at temperature 300°C and held during 120 minutes. Then sample is experienced rewarm rolling with reduction 25%, 30%, and 35%. The results obtained showed that the ultimate tensile strength and yield strength are higher proportional with the increasing of % reduction, their values are 501,1 MPa; 599,3 MPa; later decrease to 546, 5 MPa and to yield strength are 441,8 MPa; 466,1 MPa; then decrease to 458,6 MPa. Moreover hardness value increase proportional with % reduction such as 154 HV; 162 HV; after that decrease to 160 HV While, % elongation decreases inversely proportional with % reduction namely 12,4%; 8,2%; later increase to 11,2 %. It is caused of the partial recrystallization phenomenon as evidenced by the presence micron-sized.AbstrakWarm rolling merupakan salah satu metode termomekanik yang mempunyai beberapa keuntungan yaitu salah satunya menghasilkan sifat mekanik yang tinggi, namun tidak mengurunkan nilai keuletan karena adanya fenomena rekristalisasi parsial yang menghasilkan butiran baru berbentuk micron. Paper ini menjelaskan tentang hasil penelitian berupa pengaruh persentase reduksi terhadap sifat mekanis paduan Cu-Zn 70/30. Paduan Cu-Zn 70/30 setelah dilakukan proses homogenisasi dan didinginkan di udara lalu dipanaskan ke suhu 300°C, kemudian masing-masing dilakukan warm rolling dengan persentase reduksi sebesar 25%, 30%, dan 35% kemudian ditahan di suhu 300°C dalam waktu 120 menit. Selanjutnya sampel dilakukan rewarm rolling dengan persentase reduksi sebesar 25%, 30%, dan 35%. Hasil penelitian yang dilakukan antara lain nilai kekuatan tarik (UTS dan YS) yang semakin tinggi sebanding dengan peningkatan % reduksi warm rolling yaitu masing-masing untuk nilai UTS sebesar 501,1 MPa; 599,3 MPa; lalu menurun menjadi 546,5 MPa serta untuk nilai kekuatan luluh sebesar 441,8 MPa; 466,1 MPa; lalu menurun menjadi 458,6 MPa. Selain itu, nilai kekerasan meningkat sebanding dengan peningkatan % reduksi warm rolling masing-masing sebesar 154 HV; 162 HV; lalu menurun menjadi 160 HV. Sedangkan persentase elongasi semakin menurun berbanding terbalik dengan peningkatan % reduksi masing-masing sebesar 12,4%; 8,2%; lalu meningkat menjadi 11,2%. Hal tersebut disebabkan karena adanya fenomena rekristalisasi parsial yang dibuktikan dengan kehadiran butir kecil berukuran mikron.Keywords : Cu-Zn 70/30 alloy, warm rolling, anneal, % reduction, mechanical properties
GAMBARAN KESEJAHTERAAN SUBJEKTIF LANSIA YANG AKTIF DALAM KEGIATAN RELIGIUS
Authors: Kosalina Novi 
Published: June 2019

<p><em>There were images that older adults are predominantly senile, unproductive, poor in health, and useless. In fact, there are many older adults who still optimally function, such as on religious activities. Religious activities give positive impact for these older adults life. Having social support from religious community and give sense of meaning and purpose. Older adults can have subjective wellbeing, which can decrease depression risk and health problems. Subjective wellbeing is evaluation about one’s happiness, on emotional, psychological, and social aspect. This research was conducted as an effort to understanding in much deeper and more comprehensive way about subjective wellbeing in older adults who is active in religious activities. There are four subjects that involved in this research. They were 67-77 years old, widowed, and active in religious activities. This research is using interview method, conducted in about one month. Results indicate that all subjects have subjective wellbeing.</em></p><p><em> </em></p><p><strong><em>Keyword:</em></strong><em> Older Adults, Subjective Well-Being, Religious Activities</em></p>
Fractal analysis of colony margins as an aid for screening freshwater yeast cultures for bioclarification of turbid polluted water resources
Authors: Pal Sheela , Kamat Nankumar 
Published: June 2019

In Iron ore mining areas of Goa, water resources are polluted due to high turbidity and mineral colloids. For bioclarification of the turbidity, we need to identify some promising property of strains by which the strains of freshwater yeasts can be screened. This work presents a screening of freshwater yeast cultures, based on the complexity of colony margins. We performed screening of the wild aquatic yeasts isolated from different fresh water bodies of Goa on 2nd, 4th and 6th day of incubation respectively. Colony margins of sixteen different strains were studied for their fractality indexes and on comparison significant differences were observed among them. We report comparative analysis of five representative strains in this paper. Particularly strain Bchlm-1-2 showed high fractality index approximately 1410 on 6th day of incubation. This work provides quantitative scoring system of the morphological behavior of large number of strains. Our approach has the potential to improve the accuracy and speed to quantify and compare large number of isolates on the basis of their colony margins.
Non rhizobial endophytic bacteria from chickpea (Cicer arietinum L.) tissues and their antagonistic traits
Authors: Chhabra Deepika , Sharma Poonam 
Published: June 2019

Bacteria that colonize plant tissues other than rhizobia and are beneficial for plant growth referred to non rhizobial plant growth-promoting endophytic bacteria (PGPEB). This study was designed to assay the biocontrol activity of plant growth promoting endophytic bacterial isolates those found positive for P. solubilization, ACC deaminase, Indole acetic acid and Gibberelic acid production. These bacterial isolates were obtained from chickpea (Cicer arietinum L.) tissues (roots and nodules). In a previous study a total of 263 non rhizobial endophytic bacterial isolates were isolated. Out of 263 isolates, 64.5% and 34.5% were Gram positive and negative, respectively. Further for biochemical characterization, catalase, oxidase, citrate utilization, nitrate reduction, methyl red and Voges Proskauer’s tests, were performed. On the basis of P solubilization, ACC deaminase, Indole acetic acid and Gibberelic acid production 75 potential isolates were selected and screened for their biocontrol activity viz. (production of cell wall degrading enzymes, production of HCN and fluorescent pigment). Out of 75 isolates, only 29 isolates produced cellulase, 64 isolates were able to produce protease and 28 were positive for both cellulose and protease. Of 75 endophytic isolates 12 isolates (7 from root tissue and 5 from nodules tissue, respectively) were positive for HCN production and 16 isolates were found to be fluorescent pigment producer under µv ligh. As chemical fertilizers and pesticides have detrimental effects on the environment. So these bacterial endophytic isolates will be used not only as a biofertilizer because of their plant growth promotional activities but also used as an alternative of synthetic chemicals for control of several plant diseases.
Kitchen waste management by vermicomposting using locally available epigeic earthworm species
Authors: Sharma Deepshikha 
Published: June 2019

A large quantity of kitchen waste is generated in India which is either burnt, left in open or landfilled posing a serious problem of its safe disposal. To mitigate this problem all the kitchen waste can be converted into highly valuable nutrient rich vermicompost using the locally available epigeic earthworms. The biodegradable kitchen waste like vegetables, fruits, food waste etc can be cultured with earthworms to form the vermicompost by using vermitechnology. Since these vermicomposts are rich in nutrients which can replace the chemical fertilizers. In the present study the vermicomposting of kitchen waste has been attempted using locally available epigeic earthworm species of Jammu namely Amynthus diffringens, Metaphire houlleti and Octolasion tyrtaeum. The physico-chemical analysis of generated vermicomposts was carried out and compared with each other and with that of original soil sample that has been added in vermibeds prior to earthworm inoculation and addition of kitchen waste. The average values of macronutrients in the vermicompost produced by O. tyrtaeum were observed to be the highest among all types of vermicomposts i.e. Organic Carbon (OC)- 11.66 ± 0.34% , Nitrogen (N)- 1.17 ± 0.20%, Phosphorus (P)- 2.97 ± 0.32%, Potassium (K)- 1.18 ± 0.15%, Calcium (Ca)- 0.26 ± 0.04%, Magnesium (Mg)- 0.17 ± 0.04%.
Sustainable traditional dyeing of wool by Bhotia tribe in Himalayan region: A case study
Authors: Rawat Harsha , Rani Anita , Goel Alka 
Published: June 2019

Bhotia tribe is one of the community residing in the high Himalayan region of Uttarakhand state that shares the border with Tibet. The tribe is divided into five sub-groups viz., the Jadhs , Marchas, Tolchas , Shaukas and Rung. The present study was conducted in the five villages namely Lata and Chinka from Chamoli, Darkot and Baluwakot from Pithoragarh and Dunda from Uttarkashi of Uttarakhand for exploring the information from different sub-groups of Bhotia tribe about plants used by them for extracting dyes and used for traditional textile coloration in past and during present time. The rich flora of Himalayan region in Uttarakhand has been abode to varieties of plant species. The wild plant species were used by the Bhotia tribals for dyeing their woolen products. These plant dyes were obtained from jangli palak (Rumex nepalensis), bagmaru (Eupatorium), kilmora (Berberis asiatica), akhrot (Juglans regia), dholu (Rheum aystrale), tea leaves, tantri (Rheum moorcroftianum), kaphal (Myrica esculenta), darim (Punica grantum), burans (Rhodendron araborium) and harda (Terminlia chebula). Today only Shauka and Jadh tribals are using natural dyes for dyeing woolen yarn. Reasons for the reduction in usage of natural dyes among Bhotia tribals were the extinction of plant species, change in land use, natural disasters, government restriction on plucking certain plant species, the availability of synthetic dyes and colored yarns at low cost in the market. The identification of factors that led to the non-practice of sustainable dying practice among tribals for woolen craft will help in planning and conducting interventions through public, private and government organizations.
Influence of two management systems on the growth performance of adult African giant land snails (Archachatina marginata)
Authors: Dododawa Z. , Ejidike B. N. 
Published: June 2019

African gaint land snails are important as means of alleviating acute protein shortage in Nigeria livestock Industries. The present study aimed to study the influence of intensive and extensive management systems on the growth Performance of adult African Giant Land Snails (Archachatina marginata) was carried out in the wildlife domestication unit of the Department of Forest Resources and Wildlife Management, University of Benin, Benin City, Nigeria. Ninety African giant land snails (A. marginata) of average body weight 160.31g ± 0.38g were used for the study. The snails were grouped into two- Group A and Group B. 45 snails in group A were raised in an intensive system of management while 45 snails in group B were raised in an extensive system of management. The data collected on weight gain, shell length increment and shell width increment during the experiment were subjected to student t-Test at 5% significant level. Results showed that there was a significant difference at (p<0.05) in the weight gain. The intensive management system had a higher weight gain of 128.96g with mean value of 4.96 while the extensive management system had a weight gain of 88.37g with mean value of 3.40. There was no significant difference at (p>0.05) in the shell length increment. The snails in the extensive management system had the higher shell length increment of 5.32cm with mean value of 0.20 while the snails in the intensive management system had a shell length increment of 2.43cm with mean value of 0.09. There was a significant difference at (p<0.05) in the shell width increment. The snails in the extensive management system had the higher shell width increment of 9.31cm with mean value of 0.36 while the snails in the intensive management system had a shell width increment of 4.30cm with mean value of 0.17. The snails in the intensive system had a Feed Conversion Ratio of 5.03. For better growth performance of A. marginata in terms of weight gain, snail farmers should raise their snails in an intensive system of management and formulated diet should be used in feeding the snails along side with natural feed such as leaves and fruits.