Comparison between random forests, artificial neural networks and gradient boosted machines methods of on-line vis-NIR spectroscopy measurements of soil total nitrogen and total carbon

Accurate and detailed spatial soil information about within-field variability is essential for variable-rate applications of farm resources. Soil total nitrogen (TN) and total carbon (TC) are important fertility parameters that can be measured with on-line (mobile) visible and near infrared (vis-NIR) spectroscopy. This study compares the performance of local farm scale calibrations with those based on the spiking of selected local samples from both fields into an European dataset for TN and TC estimation using three modelling techniques, namely gradient boosted machines (GBM), artificial neural networks (ANNs) and random forests (RF). The on-line measurements were carried out using a mobile, fiber type, vis-NIR spectrophotometer (305-2200 nm) (AgroSpec from tec5, Germany), during which soil spectra were recorded in diffuse reflectance mode from two fields in the UK. After spectra pre-processing, the entire datasets were then divided into calibration (75%) and prediction (25%) sets, and calibration models for TN and TC were developed using GBM, ANN and RF with leave-one-out cross-validation. Results of cross-validation showed that the effect of spiking of local samples collected from a field into an European dataset when combined with RF has resulted in the highest coefficients of determination (R-2) values of 0.97 and 0.98, the lowest root mean square error (RMSE) of 0.01% and 0.10%, and the highest residual prediction deviations (RPD) of 5.58 and 7.54, for TN and TC, respectively. Results for laboratory and on-line predictions generally followed the same trend as for cross-validation in one field, where the spiked European dataset-based RF calibration models outperformed the corresponding GBM and ANN models. In the second field ANN has replaced RF in being the best performing. However, the local field calibrations provided lower R-2 and RPD in most cases. Therefore, from a cost-effective point of view, it is recommended to adopt the spiked European dataset-based RF/ANN calibration models for successful prediction of TN and TC under on-line measurement conditions

Estimation of secondary soil properties by fusion of laboratory and on-line measured vis-NIR spectra

Visible and near infrared (vis-NIR) diffuse reflectance spectroscopy has made invaluable contributions to the accurate estimation of soil properties having direct and indirect spectral responses in NIR spectroscopy with measurements made in laboratory, in situ or using on-line (while the sensor is moving) platforms. Measurement accuracies vary with measurement type, for example, accuracy is higher for laboratory than on-line modes. On-line measurement accuracy deteriorates further for secondary (having indirect spectral response) soil properties. Therefore, the aim of this study is to improve on-line measurement accuracy of secondary properties by fusion of laboratory and on-line scanned spectra. Six arable fields were scanned using an on-line sensing platform coupled with a vis-NIR spectrophotometer (CompactSpec by Tec5 Technology for spectroscopy, Germany), with a spectral range of 305-1700 nm. A total of 138 soil samples were collected and used to develop five calibration models: (i) standard, using 100 laboratory scanned samples; (ii) hybrid-1, using 75 laboratory and 25 on-line samples; (iii) hybrid-2, using 50 laboratory and 50 on-line samples; (iv) hybrid-3, using 25 laboratory and 75 on-line samples, and (v) real-time using 100 on-line samples. Partial least squares regression (PLSR) models were developed for soil pH, available potassium (K), magnesium (Mg), calcium (Ca), and sodium (Na) and quality of models were validated using an independent prediction dataset (38 samples). Validation results showed that the standard models with laboratory scanned spectra provided poor to moderate accuracy for on-line prediction, and the hybrid-3 and real-time models provided the best prediction results, although hybrid-2 model with 50% on-line spectra provided equally good results for all properties except for pH and Na. These results suggest that either the real-time model with exclusively on-line spectra or the hybrid model with fusion up to 50% (except for pH and Na) and 75% on-line scanned spectra allows significant improvement of on-line prediction accuracy for secondary soil properties using vis-NIR spectroscopy

Plant material booklet 1: palms of Malaysia

This book is intended as quick reference for landscape architects, architects and urban planners in identifying palms for landscape planning and design of open spaces, recreational areas, residential landscape and street planting. It begins with descriptions of the indigenous or introduced palms found in Malaysia. It then discuss how palms can be used as spatial articulation features in shaping human spaces. The book also includes a set of table describing eight subfamilies of palms in alphabetical order. This booklet is the first in a series of plant material booklets on the utilization of plants in landscape planning and designs. Other titles in this series include, among others, Herbs and Medicinal Plants, Wayside Trees and Bamboos in Malaysia

Evidence of bank lending channel in Malaysia

The aim of this paper is to analyse the role of banks in the transmission of monetary policy and business cycle. This paper attempts to look into the assets side as a monetary policy channel to influence economic activities. Changes in the monetary policy channel give an idea to regulate and strengthen the banking industry. The different views raise the following questions: how do changes in the monetary policy transmission affect commercial banks portfolio? If bank lending plays as a monetary policy channel, does it affect the other portfolios? Do the current regulations (such as capital requirement)affect the bank portfolio behaviour? Furthermore, Generalise Least Squares method was used to estimate the monetary changes toward commercial banks portfolio. Annual data was compiled from the year 1994 until 2004. The number of observations was based on the combination of time series and cross-sectional data, which is known as pooled data. In addition, an unbalanced bank-level panel data set for commercial banks was used. Finally, our results found that there exists a bank-lending channel in the case of Malaysia

Desain Multimedia Pembelajaran

Abstrak. Tulisan ini merupakan bagian yang tak terpisahkan dari penelitian yang berjudul: Perancangan Media Pembelajaran Berbasis Informasi Teknologi (IT). Penelitian tersebut bertujuan untuk membuat prototype sistem, metode dan pola media pembelajaran mata kuliah Nirmana Dwimatra, dengan produk akhirnya berupa rekaman di media DVD. Merancang sebuah media pembelajaran untuk mata kuliah tertentu, maka acuan awal yang sangat mendasar adalah mengetahui dan memahami isi mata kuliah tersebut, baik Tujuan Insruksional secara Umum maupun Khusus, agar tujuan perancangan dapat diidentifikasi dengan akurat. Dalam merancang media pembelajaran ini menekan proses perancangan/desain, sehingga dibutuhkan suatu metodologi khusus yang dalam hal ini disebut sebagai ‘metodologi riset desain’. Metodologi riset tersebut memiliki kekhususan tersendiri dengan melalui proses analisis, proses sintesa, dan evaluasi. Pada setiap jenjang proses tersebut dibutuhkan perlakuan khusus, terutama pada proses sintesa yang menggabungkan antara deskripsi kuantitatif dan kualitatif (dalam bentuk visual). Dengan adanya media pembelajaran seperti yang dimaksud di atas, maka diharapkan akan memudahkan pengajar dalam mengampu mata kuliahnya dan sekaligus peserta didik diharapkan relatif lebih mudah memahami materi yang disampaikan

Tentang Kemasan

Ringkasan. Pengemasan adalah suatu proses pembungkusan, pewadahan atau pengepakan suatu produk dengan menggunakan bahan tertentu sehingga produk/barang yang ada di dalamnya bisa terwadahi dan terlindungi. Pada masa lalu, pengemasan dilakukan secara tradisional dengan memanfaatkan bahan-bahan alami yang tersedia di lingkungan sekitar, seperti dedaunan atau anyaman bambu, misalnya orang membuat tempe yang dibungkus dengan daun pisang atau daun jati, atau membungkus gula aren dengan daun kelapa atau daun pisang kering. Teknologi pengemasan yang semakin maju dan modern telah hampir meniadakan penggunaan bahan pengemas tradisional tersebut, dimana pada saat ini telah beralih menggunakan bahan-bahan hasil temuan ilmu pengetahuan (sains) yang terus berkembang, yaitu antara lain dengan menggunakan bahan plastik, kaleng/logam, kertas komposit, dan lain-lain. Seiring dengan semakin berkembangnya kebutuhan dan tuntutan masyarakat dalam kehidupan keseharian, dan sejalan pula dengan kemajuan sains dan teknologi yang mengalami perkembangan sangat pesat dari waktu ke waktu, maka pada saat ini para pengusaha/industrialis menyadari sepenuhnya betapa pentingnya pengemasan (desain kemasan) dalam rangka menggerakkan sektor usaha perdagangan. Desain Kemasan menjadi perhatian utama dalam meren-canakan strategi pemasaran barang/produk yang dihasilkan untuk ditawarkan/dipasarkan kepada masyarakat konsumen

Mendesain Logo

Abstrak. Desain logo yang dirancang dengan baik akan berpengaruh secara signifikan terhadap khalayak sasaran (target audiens) yang dibidiknya, dimana tampilan visual logo dapat langsung menginformasikan bagaimana bisnis yang dikelola itu (baik berupa produk ataupun jasa) dapat memuaskan calon konsumen/klien (Cortiss, Gordon, & Nubie, 2015). Vladimir Gendelman (desainer, founder dan CEO Company Folders, Inc.) menuliskan dalam sebuah artikel bahwa Desain Logo sebuah perusahaan yang paling berhasil tidak hanya menampilkan merek perusahaan itu, namun desain tersebut juga mempresentasikan pesan/informasi dari perusahaan tersebut. Desainer logo dapat disejajarkan seperti halnya seorang ahli juru masak (master chef) yang mampu meramu/mengolah berbagai bahan makanan dalam suatu komposisi tertentu sehingga menghasilkan jenis makanan yang lezat dan menggiurkan (Gendelman, 2015). Mendesain logo selalu diawali dengan mengetahui/memahami eksistensi, visi, dan misi dari ‘entitas’ yang akan dibuatkan logonya. Selain sebagai acuan untuk mem-visualisasi-kan informasi tentang ‘entitas’ tersebut, juga sekaligus dapat digunakan dalam memilih dan menentukan jenis logo apa yang cocok untuknya. Tahapan selanjutnya, mengolah dan menata unsur-unsur visual menjadi satu kesatuan komposisi yang harmonis dan estetis, dengan tetap mempertimbangkan faktor-faktor determinan yang terkait dengan eksistensi ‘entitas’ yang bersangkutan. Kata kunci: desain, logo, perusahaan