Semakin menipisnya ketersediaan sumber energi mengakibatkan harga bahan bakar minyak menjadi tinggi. Kenaikan harga bahan bakar minyak ini berdampak pada dunia maritime. Hal ini dikarenakan kapal ...merupakan salah satu alat transportasi yang menggunakan bahan bakar minyak dalam jumlah besar. Berangkat dari permasalahan tersebut, tugas akhir ini mencoba menghadirkan satu solusi untuk mengurangi pemakaian bahan bakar minyak dengan cara memanfaatkan potensi energi angin di wilayah perairan Indonesia. energi angin tersebut digunakan sebagai penggerak towing kite yang dipasang pada Tanker 6500 DWT untuk memberikan tambahan daya dorong pada kapal dan mengurangi beban kerja mesin induk pada saat kapal beroperasi. Tujuan tugas akhir ini adalah untuk mendapatkan tipe dan ukuran towing kite yang optimum serta memiliki biaya investasi yang rendah dari beberapa jenis dan ukuran towing kite. Analisis kerja towing kite yang dilakukan adalah pada kecepatan kapal 12 knot, kecepatan angin 10,9 knot dan sudut vektor relative angin terhadap laju kapal sebesar 45°. Dari hasil analisis didapatkan towing kite yang optimum untuk dipasang di kapal adalah Skysails SKS 320 tipe Flexyfoil. Dengan menggunakan rumus teoritis didapatkan penghematan bahan bakar akibat pemasangan towing kite sebesar 3,0234 ton untuk sekali trip atau 99 , 7813 ton per tahun. Berdasar hasil analisis ekonomis, dengan biaya investasi sebesar Rp. 5.690.917.960 pemasangan towing kite diperkirakan dapat tercapai Break Even Point pada tahun ke 9 dari 20 tahun investasi.
Diurnal raptors inhabiting wetland areas where waterfowl shooting is conducted have many opportunities to ingest lead (Pb) shot pellets when feeding on their prey. Exposure to Pb shot was studied in ...the Spanish imperial eagle (Aquila adalberti), an endangered species with a world population of about 150 breeding pairs, and in the red kite (Milvus milvus) from Doñana (southwest Spain). Lead exposure was evaluated by the presence of Pb shot in the pellets of both species. Results obtained by this noninvasive method demonstrated Pb shot in 11.0% of Spanish imperial eagle and 5.5% of red kite pellets. When the data of both species were pooled, there was a significant relationship between Pb shot ingestion and consumption of waterfowl during the hunting season. Pb shot found in pellets exhibited signs of erosion, and their weight distribution had peaks at 70, 170, and 240 mg, which could correspond to ammunition used for duck and goose hunting.
Un de nos grands défis actuels est la décarbonisation du réseau électrique en éliminant les générateurs d'électricité à base de carburant, et de les remplacer de préférence par des ressources ...publiquement acceptés et qui respectent la nature de l'environnement. C'est où les ressources énergétiques renouvelables soulèvent comme une solution prometteuse. Les Systèmes de génération d'électricité à cycle de relaxation représentent notamment une classe intéressante des énergies renouvelables. Un tel système doit retrouver périodiquement un état qui permet la production d'énergie, ce qui entraîne un cycle à deux phases : une phase de génération et une phase de récupération qui consomme l'énergie. L'intérêt principal de cette thèse est focaliser sur le système de traction à base de cerf-volant, appelé par la suite le Kite Generator System (KGS). Il s'agit d'une solution proposée pour extraire l'énergie du vent stable et forte dans les hautes altitudes. Son principe de fonctionnement est d'entraîner mécaniquement un générateur électrique au sol en utilisant un ou plusieurs cerfs-volants captifs. La problématique est divisée en deux objectifs : 1 - L'optimisation et le contrôle du cycle de relaxation afin de maximiser la puissance moyenne produite par le système. Deux stratégies de contrôle sont proposées à cet effet : une basée sur un contrôle du modèle non linéaire prédictif (Nonlinear model predictive control - NMPC), et la deuxième basée sur l'application des contraintes virtuel (Virtual Constraints Control - VCC). 2 - L'Intégration du système sur le réseau électrique ou l'employer pour alimenter une charge isolée. Ces problèmes sont abordés dans cette thèse, réalisée au laboratoire de génie électrique de Grenoble (G2ELab) en collaboration avec le laboratoire d'Image Parole Signal Automatique de Grenoble (GIPSA-Lab).
One of our current major challenges is decarbonizing the electric grid by eliminating fuel based electricity generators, and replacing them preferably by nature-friendly publicly accepted resources. That is where renewable energy resources raise as a promising solution. Power relaxation-cycle systems represent an interesting and particular class of renewable. Such a system needs to regain periodically a state that allows energy production. Hence, it has two phases: A generation during which the system is working in its "power" region and is able to generate power and a recovery phase that starts when the system reaches its power region boundaries and resets the system's state to start a new generation phase, which results in power consumption. The main focus of this PhD dissertation is the kite-based traction system, named thereafter the kite generator system (KGS), which emerged as an important class of renewable energy systems that uses relaxation phases. It is a solution proposed to extract energy from the steady and strong wind found in high altitudes. Its operation principle is to mechanically drive a ground-based electric generator using one or several tethered kites. The problematic is divided into two objectives: 1 - Optimization and control of the relaxation cycle to maximize the system's average produced power. Two control strategies are proposed for this purpose: A nonlinear model predictive control (NMPC) based and virtual constraints control (VCC) based one. 2 - Integration of the system on the electric grid or employing it to supply an isolated load. These problems are addressed in this thesis, realized in Grenoble Electrical Engineering laboratory (G2ELab) with collaboration with Grenoble Image Parole Signal Automatique laboratory (GIPSA-Lab).
The author reports on her experience at the National Institute of Design (NID) in Ahmedabad, India 1994 and her role in teaching graphic design aimed at helping students to apply Indian ...aesthetics/design traditions appropriate to Western tastes. She comments on the challenges of teaching modern design techniques and demonstrates examples of the students' work (illus.)
Crvena lunja nastanjuje otvorena mozaična staništa zapadnog palearktika s najvažnijim gnijezdećim populacijama u Njemačkoj, Švicarskoj, Francuskoj i Španjolskoj. Prema istoku Europe brojnost parova ...postaje sve manja. U Hrvatskoj se sve do 2018. godine smatrala regionalno izumrlom gnjezdaricom te rijetkom zimovalicom istočne Slavonije i Baranje. Ranije se gnijezdila na istoku Hrvatske, a posljednje gniježđenje je zabilježeno 1968. godine kod Migalovaca. Nakon što je 2014. godine u Austriji, Slovačkoj i Češkoj pokrenut projekt praćenja crvenih lunja pomoću GPS/GSM i GPS/GSM/UHF uređaja, pokazalo se da mnoge od njih zalaze i u Hrvatsku. Ovaj rad daje kratak pregled rezultata dobivenih analizom podataka sa satelitske telemetrije. U razdoblju od rujna 2014. do listopada 2018.g. u Hrvatskoj je zabilježeno 39 različitih crvenih lunja označenih uređajima za praćenje te su ovdje provele sveukupno 1484 dana. Glavni period pojavljivanja crvenih lunja u Hrvatskoj je od rujna do ožujka (s vrhuncem selidbe u listopadu odnosno ožujku), dok se malobrojne ptice ovdje zadržavaju i tijekom ljetnog lutanja. Ptice koje gnijezde u srednjoj Europi kroz Hrvatsku sele u širokom pojasu, pojavljujući se u svim dijelovima zemlje pa čak i na nekim pučinskim otocima, prateći osnovni smjer JJZ do zimovališta u Italiji, dok manji broj jedinki seli u smjeru JI i zimuje u Grčkoj. Između 2014. i 2018. zabilježeno je zimovanje četiri označene crvene lunje u Hrvatskoj (po jedna ptica u Baranji, istočnoj Slavoniji, srednjoj Posavini i Pokupskom bazenu), s dolaskom na zimovališta većinom ulistopadu i odlaskom oko sredine ožujka. Terenski obilasci su pokazali da se tijekom zime crvene lunje u manjim skupinama (3-13 jed.) okupljaju na redovito korištenim noćilištima (šumarci, drvoredi i sl.) te je na dva mjesta utvrđeno zajedničko noćenje s crnim lunjama Milvus migrans. Tijekom ranog proljeća 2018. godine jedna od crvenih lunja zadržavala se u istočnoj Slavoniji južno od Đakova te se sumnjalo na mogući pokušaj gniježđenja. Radilo se o mladoj ženki s uređajem AUKI49 označenoj kao ptić prstenom C144030 tijekom 2016. godine u okolici Břeclava u Češkoj, nakon čega je u dva navrata zimovala u Italiji i redovito selila preko Hrvatske. Obilaskom terena u travnju opaženo je svadbeno ponašanje ženke i mužjaka crvene lunje bez oznake, dok je u svibnju na istom mjestu na rubu šume hrasta i graba pronađeno gnijezdo na hrastu lužnjaku i ženka koja je sjedila u njemu. Početkom lipnja tijekom provjere gnijezda nisu pronađeni mladi, već samo nekoliko pera i jedno napuklo jaje crvene lunje. Mužjak je uočen iznad šume dok je ženka netom prije napustila područje i uputila se prema Češkoj. Na temelju analize uzorka kretanja ženke tijekom proljeća odnosno činjenica utvrđenih terenskim obilascima, pretpostavlja se da se u gnijezdu najmanje jedan ptić uspješno izlegao te da je vjerojatno postao žrtvom predacije. Iako tijekom
2018.godine par crvenih lunja nije othranio nijednog ptića, nedvojbeno je dokazano ponovno gniježđenje vrste nakon 50 godina izostanka. Tijekom zimovanja i gniježđenja u Hrvatskoj crvene lunje su koristile mozaična nizinska poljoprivredna područja s manjim njivama, livadama, drvoredima i šumarcima. Noviji podaci prikupljeni tijekom zimskog prebrojavanja ptica odnosno satelitskim praćenjem ptica iz sjevernijih populacija, pokazali su da je crvena lunja redovita preletnica u čitavoj Hrvatskoj te redovita zimovalica, prvenstveno u istočnoj Slavoniji i Baranji. Gnijezdeća populacija crvene lunje u srednjoj Europi pokazuje blago rastući trend te se u narednim godinama može očekivati eventualni pronalazak novih gnijezdećih parova i u Hrvatskoj.
A pelagic and/or mid water trawl using canvas kites as net-mouth opening device was developed. The wing kites for horizontal net-mouth opening and the para-kites for vertical opening were designed ...and the optimum dimension of kites was determined according to the drag of a trawl net of 25.96m in total length. As a result of sea trials using the trawl net, the height of the net-mouth was kept to be 6.03m on average and little change in the height of the net-mouth was observed, within the wide towing speed from 1.55m/s to 2.58m/s. The depth of the cod-end was also maintained at the same level as the center of the net-mouth. The drag of the trawl net was approximately 17.8kN at a towing speed of 2.06m/s (4knot). In addition, working depth of the net was controllable with change in the warp length, but at a given warp length the depth of mid water trawl with canvas kites was almost half of that of the one with conventional otter boards.
We studied the diets of nesting Swallow-tailed Kites (Elanoides forficatus) at eight nests in 1988–1989 in southern Florida, where the species reaches its greatest abundance in the United States. ...Males fed females during the incubation stage an average of 2.1 ± 0.8 times per day. The adults averaged 10.9 ± 4.5 deliveries daily during the nestling stage, and 10.3 ± 12.5 deliveries to young daily following nest departure. Vertebrates comprised 97% of the biomass for the 1092 identifiable prey items delivered to nests. Frogs accounted for 56%, birds 30%, and reptiles 11% of all prey. Numerically, frogs made up 83% of the reptile and amphibian prey. The relative proportions of prey types varied substantially among nests within years, and significantly more snakes and insects were delivered in 1989. Total biomass delivered in 1988 did not differ from that in 1989. Bird biomass, however, was greater in 1988 and insect biomass was greater in 1989. Anoles and snakes were brought to nests in larger numbers during the morning and evening hours; and birds were delivered mainly from midmorning to midafternoon. Entregas de Alimentos en Nidos de Elanoides forficatus en el Sur de Florida Resumen. Durante 1988 y 1989 estudiamos la dieta de los polluelos de Elanoides forficatus en ocho nidos localizados en el sur de la Florida, donde la especie alcanza su mayor abundancia de nidificacion dentro de los Estados Unidos. Durante la incubación, los machos alimentaron a las hembras un promedio de 2.1 ± 0.8 veces por día. Durante la etapa de polluelos, los adultos hicieron un promedio de 10.9 ± 4.5 entregas diarias y un promedio de 10.3 ± 12.5 entregas diarias después de abandonar el nido. Los vertebrados comprendieron el 97% de la biomasa de las 1092 presas identificables entregadas en los nidos. Las ranas constituyeron el 56%, las aves el 30% y los reptiles el 11% del total de las presas. Numéricamente, las ranas constituyeron el 83% de la herpetofauna depredada. Las proporciones relativas de los tipos de presa variaron substancialmente entre los nidos a través de los años, y considerablemente más serpientes e insectos fueron entregados en 1989. La biomasa total entregada durante 1988 no difirió de la observada en 1989. Sin embargo, la biomasa de las aves fue mayor en 1988, mientras que la de los insectos fue mayor en 1989. Las lagartijas y serpientes fueron entregadas a los nidos en mayor cantidad durante las horas de la mañana y de la tarde, mientras que las aves fueron entregadas principalmente desde la mitad de la mañana hasta la mitad de la tarde.
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