There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Sustainable composite material based on surface-modified rape straw and environment-friendly adhesive

https://iopscience.iop.org/article/10.1088/1755-1315/105/1/012010/pdf

Design optimization of hybrid biomass and wind turbine for minapolitan cluster in Domas, Serang, Banten, Indonesia

http://library.um.ac.id/free-contents/downloadpdf.php/buku/introduction-to-physical-metallurgy-sidney-h-avner-30435.pdf

Introduction to physical metallurgy / Sidney H. Avner

/pdf/body-design-concept-of-remotely-operated-vehicle-rov-of-4v8qbjeif7.pdf

Body Design Concept of Remotely Operated Vehicle (ROV) of Observation Class with the Method of Concept Screening and Concept Scoring

The flyover development today is very much at all to do because it is one solution as degrading congestion and lifter segment flyover is one important tool in the construction of flyovers. This final project offers an example of the calculation and planning lifter segment fly over the beam structure for lifting can be separated pairs which can later be changed in accordance with the specification segment flyover to be lifted. The final project is expected to be one of the references manufacture segments lifter fly over. This design uses Pahl and Beitz method and the results of this research. Specifications lifter segment fly over with beam structure for lifting to be loose tide is Lifting Equipment; Wire rope with two types of options on each drum are strands left and right torsion. Mechanism trolley; Can move on the path along the 3,019 mm, diameter the wheel trolley 381 mm, Trolley the wheel shaft diameter: 12 cm or 120 mm with material JIS S45C. Struktur lifter ; Beam lifting using a beam with a weight per unit length of 1.97 N / mm with JIS G3101 SS540 material along the 4900 mm and a surface area of retaining cylindrical pedestal A of 5024 mm2 with material JIS G3101 SS540. The mechanism of motion lifter can move on the path along the 4000 mm. Wheel lifter diameter 533.4 mm. Hydraulic of lifters driver using a double acting hydraulic with a maximum

https://jurnal.untirta.ac.id/index.php/vanos/article/download/9123/6711

Design of Lifter Flyover Segment with a Structure of Lifting Beam can Escape Pairs

Use of NACA 0012 at the Sultan Wind Turbine prototype provide value coefficient power turbine at wind speed 5.5 m / s by 0017 , wind speed 6.1 m / s at 0.015 , wind speed 7.7 m / s at 0.016 , wind speed 6.5 m / s for 0018 and wind speed 6.2 m / s by 0017 . Where the value of the highest efficiency obtained at a speed of 6.5 m / s at 0.018 . This result is not as expected to generate sufficient energy.The next development carried out investigations on some kind of airfoil, from investigations obtained by using Qblade software that NACA 6612 has a value of 1.78 CL at 15 degrees angle of attack is the largest of all the airfoil .In this research, NACA 6612 will be simulated with a variable chord length, angle of attack, and wind speed, of these three variables will be created which will map graphics 3d sliding value of the ratio of the 3 variables, this graph will give recommendations most optimum combination of variables to types are mapped wind speed throughout the year, to produce optimum power.Optimum combination of NACA 6612 with wind speed varied from 2-7 m/s is chord length 30 cm and angle of attack 7 degree.

Development of the Third Darrieus Blade of Sultan Wind Turbine for Low Wind Speed

Particle boards are widely used as furniture materials in the world. The particle boards on the market have a disadvantage that is when this materials contact with water, the mechanical properties decrease significantly. Material engineering is carried out by changing the particle board composition and other factors. One of the factors that influence the quality of particle board is wood sawdust mesh. Filler mesh combinations are carried out to obtain the best quality particle board. The result of experiment refers to SNI 03-2105-2006 for some mechanical properties, such as density, thickness swelling, hardness, bending strength, and impact toughness. The compositions of particle board in this research are 15% fibre of oil palm, 50% wood sawdust, 15% resin epoxy and 20% polyvinyl acetate (PVAc). Samples were carried out by cold press single punch method with pressure 30 bar. The result from this research known that the best mechanical properties of particle board on filler mesh combination M40-60-80, those are: density 0.95 g/cm3, thickness swelling 1.93%, hardness 29.30 N/mm2, bending strength 16.38 MPa, and impact toughness 3.38 kJ/m2. This value has exceeded the particle board on the market.

/pdf/the-effect-of-wood-sawdust-mesh-combination-on-mechanical-1raserebh4.pdf

The Effect of Wood Sawdust Mesh Combination on Mechanical Behaviour of Particle Board

Potensi limbah tandan kosong kelapa sawit yang kurang dimanfaatkan menjadi inspirasi untuk pembuatan papan komposit dari limbah tersebut. Pembuatan papan komposit dari limbah tandan kelapa sawit bertujuan untuk menghasilkan produk furniture yang ramah lingkungan dan memiliki karakteristik yang lebih baik dibandingkan yang ada di pasaran. Bahan yang digunakan adalah serat tandan kelapa sawit, serbuk kayu sengon resin epoxy dan PVAc. Fraksi volume dari komposit ini adalah serat tandan kelapa sawit 15%, serbuk kayu 50%, resin epoxy 15% dan lem fox 20%. Pembuatan bahan dilakukakn dengan metode cold press single punch dengan tekanan 300 kg/cm2. Karakteristik bahan yang diteliti yaitu densitas, pengembangan tebal, kekerasan, impak, bending serta pengamatan struktur mikro. Dari hasil pengujian diperoleh papan komposit dengan karakteristik optimum yaitu pada panjang variasi serat 15 mm. Papan komposit variasi panjang 15 mm memiliki nilai densitas 0.973 g/cm3, pengembangan tebal 1.025%, kekerasan 26 N/mm2, nilai max force 41.904 N, batas elastisitas 904, 745 N/mm2, nilai impak 8.247 kj/m2.

https://jurnal.untirta.ac.id/index.php/jwl/article/download/520/404

Rina Lusiani

Papers

Body Design Concept of Remotely Operated Vehicle (ROV) of Observation Class with the Method of Concept Screening and Concept Scoring

Design of Lifter Flyover Segment with a Structure of Lifting Beam can Escape Pairs

Development of the Third Darrieus Blade of Sultan Wind Turbine for Low Wind Speed

The Effect of Wood Sawdust Mesh Combination on Mechanical Behaviour of Particle Board

Pemanfaatan limbah tandan kosong kelapa sawit sebagai papan komposit dengan variasi panjang serat