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THE SCIENTIFIC METHOD

What is science? How is it different from other ways of thinking? and what are scientists like? How do they think and what do they mean when they talk about doing science? Science isn't just test tubes or strange apparatus. And it's not just frog dissections or names of plant species. Sciences is way of thinking, a vital, ever-growing way of looking at the world. It is a way of discovering how the world works a very particular way that uses a set of rules devised by scientists to help them also discover their own mistakes. Everyone knows how easy it is to make a mistake about the things you see or hear or perceive in any way. If you don't believe it, look at the two horizontal lines on the previous page. One looks like a two way arrow; the other has the arrow heads inverted. Which one do you think is longer (not including the arrow heads)? Now measure them both. Right: They are exactly the same length. Because it's so easy to go wrong in making observations and dra
Recent posts

Jurnal: PERPINDAHAN PANAS DAN MASSA PADA PENGEMBUNAN CAMPURAN METANOL-PROPANOL UDARA DALAM KONDENSOR TEGAK

Pengembunan campuran uap yang mengandung gas sering dijumpai di industri. Penelitian mengenai pengaruh gas pada proses pengembunan telah banyak dilakukan. Pengaruh tersebut diantaranya adalah penurunan koefsien perpindahan panas rerata pada pengembunan campuran uap air dan udara (Lee et al., 2001) dan meningkatkan hambatan permukaan dan menurunkan estimasi nilai koefisien pengembunan (Takaharu and Yurika, 2003), mempengaruhi kurva karakteristik perpindahan kalor kondensasi terutama pada daerah hambatan difusi pada pengembunan campuran uap-air, etanol dan udara (Wang and Utaka, 2004; Wang and Utaka, 2005). Pada pembangkit listrik tenaga panas bumi, keberadaan gas mempengaruhi kinerja termodinamiknya (Gokcen and Yildirim, 2008).

Jurnal: Vehicle Routing Problem with Backhaul, Multiple Trips and Time Window

Abstract: Transportation planning is one of the important components to increase efficiency and effectiveness in the supply chain system. Good planning will give a saving in total cost of the supply chain. This paper develops the new VRP variants’, VRP with backhauls, multiple trips, and time window (VRPBMTTW) along with its problem solving techniques using Ant Colony Optimization (ACO) and Sequential Insertion as initial solution algorithm. ACO is modified by adding the decoding process in order to determine the number of vehicles, total duration time, and range of duration time regardless of checking capacity constraint and time window. This algorithm is tested by using set of random data and verified as well as analyzed its parameter changing. The computational results for hypothetical data with 50% backhaul and mix time windows are reported.

Jurnal: Production Inventory Models for Deteriorating Items with Stochastic Machine Unavailability Time, Lost Sales and Price-Dependent Demand

Abstract: The economic production quantity (EPQ) model is widely employed in reality and is also being intensively developed in the research area. This research tries to develop more realistic EPQ models for deteriorating items by considering stochastic machine unavailability time (uniformly and exponentially distributed) and price-dependent demand. Lost sales will occur when machine unavailability time is longer than the non production time. Since the closed form solution cannot be derived, we use Genetic Algorithm (GA) to solve the models. A numerical example and sensitivity analysis is shown to illustrate the models. The sensitivity analyses show that a management can use price policy to minimize the profit loss due to machine unavailability time under a price- dependent demand situation.

Jurnal Bahasa Inggris: Mathematical Method for Predicting Nickel Deposit Based on Data from Drilling Points

Abstract: In this article we discuss several methods for predicting nickel ore content inside the soil under a given area/region. The prediction is the main objective of the exploration activity which is very important for conducting the exploitation activity from economic point of view. The prediction methods are based on the data obtained from the drilling activity at several „points‟. The data yields information on the nickel density at those points. Nickel density over the region is approximated (with an approximate function) by applying interpolation and/or extrapolation based on the data from those points. The nickel content is predicted by applying integral of the approximate function over the given region.

Jurnal Bahasa Inggris: Toward Modernization and Internationalization (M&I) of Higher Education Institution

Abstract: Knowledege based economy will be a matter of time for Indonesia’s future competitiveness. Therefore, to get there, several basic requirements have to be early prepared. Among others, human capital is perhaps the most important requirement for a country to be able to develop an economic condition based on the capability and capacity of knowledge. Human capital is not just Indonesia concern, it is the concern of all countries. In fact, only some countries can create a condition for human capital to grow effectively and efficiently.

Jurnal: Model Persediaan Multi Item dengan Mempertimbangkan Faktor Kadaluarsa dan Faktor All Unit Discount

        Persediaan berkaitan dengan penyimpanan suatu bahan baku/barang yang bertujuan untuk menun-jang kelancaran suatu sistem produksi atau ke-giatan bisnis yang dilakukan oleh sebuah peru-sahaan. Pengadaan persediaan yang terlalu banyak akan menyebabkan perusahaan mengeluarkan biaya yang besar untuk menyimpan bahan baku/ barang tersebut, seperti biaya perawatan, biaya sewa, atau biaya asuransi.