1,720,955 research outputs found
Konstanta Pembentukan Biogas dari Limbah Cair Pabrik Kelapa Sawit (LCPKS) Menggunakan Pemodelan Gompertz yang Dimodifikasi pada Variasi Laju Pengadukan
No full textResearch on the process of making biogas from Palm Oil Liquid Waste (LCPKS) has been carried out. The study was conducted by varying the rate of mixing (ω). The research objective was to determine the effect of the mixing rate on the production of biogas produced and the kinetic constant of the modified Gompertz equation. The material used is LCPKS and Starter with a ratio of 80: 20. The method of making biogas is carried out by a one-stage anaerobic digestion process in a 6000 ml batch reactor. The reactor is operated at 55 ° C. Mixing rate variations (ω) are 100 rpm, 150 rpm, 200 rpm, 250 rpm and 300 rpm. The analysis is carried out on solids (VS, VSS, and COD) and gas (biogas volume and composition). The process has been stopped when VS (volatile solid) value has been achieved and the biogas volume accumulation is constant. The best results were obtained at ω 200 rpm which produced a total biogas of 121.43 ml / g VS, with the composition: methane (91.84%), carbon dioxide (8.15%), and hydrogen sulfide (0.0123%). The best overall degradation of VS and COD was obtained at ω 200 rpm in the amount of 68.18% and 59.68%. The accumulated biogas yield produced is then modeled using the modified Gompertz equation and analyzed using the non-linear regression method. Obtained the best kinetic parameters A, Rmax, and λ at ω 200 rpm, namely 150.479 ml / g VS, 94.721 ml / g VS, and 1.591 days. The difference in biogas results predicted and measured at ω 200 rpm is 0.98% with the coefficient of determination (R2) and root-mean-square error (RMSE) is 0.999 and 5.258. The results of R2 and RMSE show that making biogas can be modeled using a modified Gompertz model.Penelitian tentang proses pembuatan biogas dari Limbah Cair Kelapa Sawit (LCPKS) telah dilakukan. Penelitian dilakukan dengan memvariasikan laju pengadukan (ω). Tujuan penelitian untuk mengetahui pengaruh laju pengadukan terhadap produksi biogas yang dihasilkan dan konstanta kinetik persamaan Gompertz yang dimodifikasi. Bahan yang digunakan adalah campuran LCPKS (LCPKS: Starter = 80 : 20) pada pH 7±0,2. Metode pembuatan biogas dilakukan dengan proses digestasi anaerobik one-stage pada reaktor batch 6000 ml. Reaktor dioperasikan pada temperatur 55 °C. Variasi laju pengadukan (ω) yaitu 100 rpm, 150 rpm, 200 rpm, 250 rpm, dan 300 rpm. Analisis yang dilakukan yaitu terhadap padatan (VS, VSS, dan COD) dan gas (volume dan komposisi biogas). Proses dihentikan pada saat dicapai nilai VS (volatile solid) dan akumulasi volume biogas konstan. Hasil terbaik didapat pada ω 200 rpm yang menghasilkan total biogas sebesar 121,43 ml/g VS, dengan komposisi: metana (91,84%), karbon dioksida (8,15%), dan hidrogen sulfida (0,0123%). Degradasi keseluruhan VS dan COD terbaik diperoleh pada ω 200 rpm yaitu sebesar 68,18 % dan 59,68 %. Akumulasi yield biogas yang dihasilkan kemudian dimodelkan menggunakan persamaan Gompertz yang dimodifikasi dan dianalisis menggunakan metode regresi non-linier. Diperoleh parameter kinetik A, Rmax, dan λ terbaik pada ω 200 rpm yaitu 150,479 ml/g VS, 94,721 ml/g VS, dan 1,591 hari. Perbedaan hasil biogas yang diprediksi dan diukur pada ω 200 rpm ialah 0,98% dengan koefisien determinasi (R2) dan root-mean-square error (RMSE) sebesar 0,999 dan 5,258. Hasil R2 dan RMSE menunjukkan bahwa pembuatan biogas dapat dimodelkan menggunakan model Gompertz yang dimodifikasi.106 HalamanSkripsi Sarjan
Pengaruh Laju Pengadukan Terhadap Stabilitas Digester Anaerobik Satu Tahap pada Pembentukan Biogas dari Limbah Cair Pabrik Kelapa Sawit Menggunakan Lab Scale Reaktor Batch
Full text linkMixing is essential to increase the efficiency of interactions between active microbes and organic matter during the anaerobic digestion process. The purpose of this research is to study the effect of mixing rate on the stability of one stage anaerobic digesters in biogas production in terms of pH and alkalinity. The production of biogas from palm oil mill effluent was carried out in a 6000 ml batch reactor at varying mixing rates: 100 rpm, 150 rpm, 200 rpm, 250 rpm, and 300 rpm. The reactor is operated with a mixture condition maintained at a pH of 7 ± 0.2 and an operating temperature of 55 ° C. NaHCO3 is added to the mixture to control and maintain the pH of the mixture. Analysis of pH and alkalinity is carried out every day to see the reactor stability. The best results were obtained at a mixing rate of 200 rpm with the pH produced stable during the process is 7. The alkalinity profile produced at each mixing rate was relatively stable with an alkalinity range is 3500-4500 mg/L. The best mixing rate is 200 rpm with a stable pH and alkalinity and the highest biogas production is 457 ml/day
Penerapan Konseling Kelompok Untuk Mengurangi Kecanduan Game Online Pada Siswa
Full text linkOnline game addiction is a form of addiction caused by internet technology which makes a person very attached to playing online games, from time to time there will be an increase in frequency and duration. Online games are games that are very popular and popular among teenagers, including students. Online games have a bad influence on students if they are played for an excessive amount of time so that addiction to online games causes students to reduce their study time. The aim of this research is to determine the reduction of online game addiction through group counseling services for students. The method in this research uses a quantitative approach with a One Group Pretest and Posttest design. The research sample consisted of 5 students based on the recommendation of the guidance and counseling teacher using purposive sampling technique. The data collection technique uses a questionnaire to measure students\u27 level of online game addiction. The research results showed that there was a significant reduction after providing treatment through group counseling in the level of online game addiction with a calculated t value of 20,250 which was greater than the t table of 2,131 (20,250>2,131). This means that the alternative hypothesis (Ha) is accepted and the null hypothesis (Ho) is rejected. It can be concluded that research shows that the application of group counseling can reduce online game addiction in student
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
