PRODUKSI DAN KARAKTERISASI BAHAN BAKAR TERBAHARUI DARI SAMPAH PERKOTAAN (REFUSE DERIVED FUEL)

ABSTRAKSebahagian besar kota di negara-negara berkembang menghadapi masalah serius dalam penanganan sampah perkotaan. Metode pengelolaan sampah perkotaan konvensional yang umum dilakukan menyebabkan dampak lingkungan, khususnya terkait dengan emisi gas rumah kaca (Green House Gas, GHG) dan lindi dari Tempat Pembuangan Akhir (TPA). Di sisi lain, pemenuhan kebutuhan energi tidak sebanding dengan pesatnya pertumbuhan penduduk dan ekonomi karena kekurangan sumber daya alam. Penelitian ini bertujuan mengevaluasi potensi pemanfaatan sampah perkotaan sebagai sumber bahan bakar terbaharui. Bahan bakar terbaharui dari sampah perkotaan biasa disebut sebagai Refuse Derived Fuel (RDF) diproduksi dengan menvariasikan kandungan sampah organik antara 0-80%, dan ukuran partikel 4, 6, 8 dan 12 mesh. Selanjutnya karakteristik RDF ditentukan berdasarkan proksimat dan ultimat analisis, serta uji nilai bakar untuk menentukan nilai kalor rendah (Low Heating Value, LHV). Dari hasil penelitian diketahui bahwa LHV tertinggi 7.016 kkal/kg diperoleh pada RDF dengan kandungan sampah organik sebesar 0% dan ukuran partikel sebesar 6 mesh. Dari data juga menunjukkan bahwa RDF dapat digunakan untuk mensubtitusi sebagian batubara dalam proses pembakaran utama dan kalsinasi industri semen dengan kandungan sampah organik masing-masing 60% dan 80%, dengan LHV sekitar 5.137 dan 4.542 kkal/kg.Kata kunci: sampah perkotaan, emisi gas rumah kaca, bahan bakar terbaharui, refuse derived fuel, negara-negara berkembang, Indonesia

PENGARUH PERAN GURU SEBAGAI MOTIVATOR TERHADAP HASIL BELAJAR SISWA PADA MATA PELAJARAN PRODUKTIF ADMINISTRASI PERKANTORAN DI SMK BINA WISATA LEMBANG

Penelitian ini dilakukan di SMK Bina Wisata Lembang. Permasalahan yang menjadi kajian dalam penelitian ini adalah belum optimalnya hasil belajar siswa pada mata pelajaran produktif Administrasi Perkantoran, hal ini dibuktikan dengan masih terdapat siswa yang belum memenuhi Kriteria Ketuntasan Minimal (KKM). Peran guru sebagai motivator merupakan faktor yang diduga memiliki pengaruh terhadap hasil belajar siswa. Oleh karena itu penelitian ini mengkaji seberapa besar pengaruh peran guru sebagai motivator (x) terhadap hasil belajar siswa (y). Penelitian ini menggunakan metode survey dengan teknik pengumpulan data menggunakan angket. Responden adalah siswa kelas X jurusan Administrasi Perkantoran SMK Bina Wisata Lembang sebanyak 90 orang. Teknik analisis data menggunakan analisis regresi. Hasil penelitian menunjukkan bahwa: (1) peran guru sebagai motivator pada mata pelajaran produktif Administrasi Perkantoran di SMK Bina Wisata Lembang berada pada kategori tinggi, (2) hasil belajar siswa pada mata pelajaran produktif Administrasi Perkantoran di SMK Bina Wisata Lembang berada pada kategori rendah, (3) hasil analisis regresi menunjukkan bahwa peran guru sebagai motivator berpengaruh positif dan signifikan terhadap hasil belajar siswa. ; This research was held in SMK Bina Wisata Lembang. The problems to be studied in this research was an ineffective study results in productive Office Administration subject, this is proved because some student still not reach the minimum completeness criteria (KKM). The role of teachers as motivator is one of the factors that maybe have an influence towards the result of students learning. Therefore, this research examines how big the role of teachers as motivator (x) for the result of student learning (y). This research uses survey method with technique of collecting data questionnaires. The respondent is the student from grade X of Offce Administration class SMK Bina Wisata Lembang for 90 people. The technique of data analysis using regression analysis. The result of the research indicate that: (1) the role of teachers as motivator in productive Office Administration subject in SMK Bina Wisata Lembang was in a high category, (2) the result of the student learning in productive Office Administration subject in SMK Bina Wisata Lembang was in a low category, (3) the result of regression analysis indicate that the act of teachers role as motivator has a positive and significant influence towards the result of students learning

Predicting field performance of five irrigated tree species using seedling quality assessment in Burkina Faso, West Africa

Five exotic tree species (Acacia angustissima (Mil.) Kuntze, Acacia mangium Wild, Gliricidia sepium (Jacq.) Alp., Leucaena hybrid (LxL), and Leucaena leucocephala (Lam.) de Wit) were investigated to determine whether parameters of nursery seedling stock quality could be used to predict their field performance in a plantation irrigated with treated waste-water to produce fodder and wood. Plants were grown in the nursery in two contrasting rooting substrates (ordinary nursery soil and sand), predicted to have different effects on resource allocation. Three categories of morphological indicators were measured, i.e. plant dimensions (height, diameter, root length), plant weights (shoot, root and whole plant weights) and indices (sturdiness quotient ‘SQ’, shoot:root dry weight ratio ‘SRR’ and Dickson’s quality index ‘DQI’). In the nursery, all species performed better in the ordinary nursery soil for all growth parameters except root length. Thus ordinary nursery substrate appeared superior to sand in terms of plant quality. However, a follow up at plantation phase revealed that only some morphological attributes or ratios were suitable to predict field performance for the five tested species in irrigated plantation. In addition, the effect of the substrate observed at the nursery stage had disappeared 12 months after out planting due to the availability of water and nutrients provided by the treated waste water used for the irrigation. The results showed that root collar diameter and DQI appeared to be the most appropriate indicators to predict the outplanting performance of the five tested species in a short-rotation irrigated plantation in semi-arid Burkina Faso. The former measure is simpler and non-destructive

Fattori di influenza per il dimensionamento di sistemi solari termici: analisi comparata delle procedure di determinazione della frazione solare e definizione di una scala di rendimenti

Questa tesi di laurea nasce in un contesto di grande sensibilizzazione verso i temi riguardanti l’ambiente, il risparmio energetico e l’utilizzo di fonti rinnovabili. Stante questo “humus” culturale, si ingenera naturalmente un’attenzione particolare verso tutti quei fattori in grado di influenzare la concezione progettuale di queste fonti energetiche. Obiettivo della presente tesi di laurea è indagare su quanta parte abbia nella determinazione della resa dei sistemi solari la procedura di calcolo adottata e su quanto le raccomandazioni sull’inclinazione delle superfici di captazione solare siano da essa influenzati. Le diverse procedure di calcolo, il cui numero è evidentemente molto elevato, sono state applicate ad un caso pratico di un edificio adibito ad uso uffici di cui si sono analizzati nel dettaglio tutti i dati sensibili, dal punto di vista energetico, dei vari componenti. Ad una prima applicazione limitata alla produzione di ACS (acqua calda sanitaria) segue una seconda per la produzione combinata di ACS e integrazione del riscaldamento. Gli obiettivi di preminente interesse, che ci si è posti a principio dell’indagine, sono due. Il primo è quello di definire qualitativamente e quantitativamente, ove possibile, quale ruolo rivesta la scelta del modello di calcolo nella determinazione della percentuale di copertura del fabbisogno, (frazione solare f), che può essere garantita da un’installazione di pannelli solari, stante la presenza in letteratura di diverse procedure di determinazione della radiazione solare incidente su una superficie. Il secondo obiettivo è quello di stabilire una scala di rendimenti delle diverse tipologie di collettori prese in considerazione e parimenti di individuare, se vi siano e in che misura, difetti procedurali nella determinazione medesima

Access control: AAAA where the first two As stand for Ability Authentication

We investigate the notion of authentication procedure. We show how this can be split in several phases: establishing that an ability can be performed, deducing a certain information from such an ability, witnessing the authenticity of the information deduced by the ability. In our framework, ability means that that one is able to perform role in a protocol. We argue that the concept of ability authentication is more general that the one of identity authentication, that is commonly used in AAA systems. We then develop an architecture for managing abilities and we show some application scenarios

The emerging role of the inwardly rectifying K+ channels in autism spectrum disorders and epilepsy

Autism is a complex behavioral disorder that develops prior to age three years and is distinguished by high heritability. Many genes predisposing to autism spectrum disorders (ASDs) have been identified. These findings have demonstrated that ASDs are etiologically heterogeneous; although, the mutations underlying ASDs are identifiable only in a minority of patients. Indeed, the causes of ASDs are unknown in more than 70% of patients. Recently, we have described two unrelated families whose affected individuals display a characteristic triad of symptoms of autism; such as impairments in social interaction, impairments in communication, restricted interests and repetitive behavior. They also displayed other symptoms commonly observed in autistic individuals; such as gait imbalance, clumsiness, mental retardation and epilepsy. The genetic analysis of these families resulted in the identification of new heterozygous point mutations in the KCNJ10 gene that encodes the inwardly-rectifying K+ channel Kir4.1 expressed predominantly, but not exclusively, in astrocytes. Functionally, the mutated channels exhibited a phenotype consistent with gain-of-function defects. These new findings highlight the emerging role of inwardly-rectifying K+ channels and astrocyte dysfunction in autism spectrum disorders associated with epilepsy.peer-reviewe

Componente di Sicurezza del TIX e della Infrastruttura di RTRT - Indicazioni tecniche per le fasi di progettazione e gestione

TIX (Tuscany Internet eXchange) is a Neutral Access Point (NAP) to promote territorial connectivity cover of Tuscany region for Public Local Government that belongs to RTRT (Tuscany Data Transmission Network) Infrastructure. Starting from TIX planning analysis, we provide a description of the process to secure and protect TIX indicating strategies and methodologies to improve the security system level

Anonymous crypt P2P. A model for a secure and private communication

The aim of this work is to contribute to the modelling of a peer-to-peer protocol in order to fill a lack that still remains in the wide panorama of developed model, i.e. .e. a deterministic anonymous and crypt peer-to-peer communication system. This work considers first the most important model confirmed by the diffusion and the reliability for their purposes, presenting an overview that focuses on the main characteristics. Than an analysis of the requirements is done and two different strategies are analysed, building two models for different anonymity and security levels. The two models are discussed and a communication protocol for a minimal user client interface is described. Finally the scalability problem is discussed

Do Political Factors affect Government Health Spending? Empirical Evidence from Sub-Sahara African Countries

In Sub-Saharan Africa (SSA), access to essential health care services remains problematic. The financing of health care is mainly provided by private sources, mainly out-of-pocket payments which represent respectively 53.12% and 36.73% of total health expenditure in 2016. As for public health expenditure, essential for ensuring universal health coverage, it represents only about 35% of health expenditure. Thus, the increase in public spending on health from domestically sources proves to be a major challenge for the countries of the region in the prospect of reaching the SDG relating to health by 2030. This paper aims to analyse the determinants of domestic government health spending in SSA by focusing on political factors. We use data from 39 SSA countries covering the period 2010-2016 and panel-corrected standard errors method for empirical investigation. The results show that democracy favours an increase in government health spending. Furthermore, a political competitive environment, the guarantee and the protection of civil liberties and political right, accountability, government effectiveness and political stability are decisive for increasing government health spending. The results also showed that political participation does not affect public health spending. These results indicate that improving political factors is essential to increase public spending in SSA