Interpretable machine learning with an eye for the physics: Hyperspectral Vis/NIR “video” of drying wood analyzed by hybrid subspace modeling

Chemometric multivariate analysis based on low-dimensional linear and bilinear data modelling is presented as a fast and interpretable alternative to more fancy “AI” for practical use of Big Data streams from hyperspectral “video” cameras. The purpose of the present illustration is to find, quantify and understand the various known and unknown factors affecting the process of drying moist wood. It involves an “interpretable machine learning” that analyses more than 350 million absorbance spectra, requiring 418 GB of data storage, without the use of black box operations. The 159-channel high-resolution hyperspectral wood “video” in the 500–1005 nm range was reduced to five known and four unknown variation components of physical and chemical nature, each with its spectral, spatial and temporal parameters quantified. Together, this 9-dimensional linear model explained more than 99.98% of the total input variance.

Plasma-wall self-organization in magnetic fusion

This paper introduces the concept of plasma-wall self-organization (PWSO) in magnetic fusion. The basic idea is the existence of a time delay in the feedback loop relating radiation and impurity production on divertor plates. Both a zero and a onedimensional description of PWSO are provided. They lead to an iterative equation whose equilibrium fixed point is unstable above some threshold. This threshold corresponds to a radiative density limit, which can be reached for a ratio of total radiated power to total input power as low as 1/2. When detachment develops and physical sputtering dominates, this limit is progressively pushed to very high values if the radiation of non-plate impurities stays low. Therefore, PWSO comes with two basins for this organization: the usual one with a density limit, and a new one with density freedom, in particular for machines using high-Z materials. Two basins of attraction of PWSO are shown to exist for the tokamak during start-up, with a high density one leading to this freedom. This basin might be reached by a proper tailoring of ECRH assisted ohmic start-up in present middle-size tokamaks, mimicking present stellarator start-up. In view of the impressive tokamak DEMO wall load challenge, it is worth considering and checking this possibility, which comes with that of more margins for ITER and of smaller reactors.

Analysis and Output Power Control of Unidirectional Secondary-Resonant Single-Active-Half-Bridge DC-DC Converter

Development of high-frequency-isolated DC-DC converters is underway for charging and discharging electric vehicle batteries. As a charger, a Single Active Bridge (SAB) converter, which is composed of a primary full-bridge converter, a high-frequency transformer, and a secondary full-bridge diode rectifier circuit, has been proposed as a unidirectional high frequency isolated DC-DC converter. In this paper, as a simple circuit configuration, a Secondary-Resonant Single-Active-Half-Bridge (SR-SAHB) converter, in which the primary and secondary circuits of the SAB converter are both half-bridge circuits, and a resonant capacitor connected in parallel to each secondary diode, is created. Due to the partial resonance on the secondary side, power transmission with unity transformer turn ratio and unity voltage conversion ratio can be realized, and a high total input power factor of the transformer can be achieved. As a result, the maximum voltage and current of the switching devices and the transformer voltage can be reduced. Moreover, soft switching in all commutations can be realized. The operation waveform is analyzed, and output power control is derived using the variable frequency control method. The effectiveness of the proposed SR-SAHB has been verified by experimental results using a 2.4 kW 20 kHz, 265V laboratory prototype.

Energy Balance in Wastewater Systems with Energy Recovery: A Portuguese Case Study

This paper presents and discusses the application of a novel energy balance scheme for assessing energy efficiency in wastewater systems. The energy balance is demonstrated with a Portuguese real-life case study, using mathematical modelling to estimate the different energy components and to compute two energy efficiency indices. The total inflow intrinsic energy can represent a significant amount (>95%) of the total energy used in systems mainly composed of gravity sewers. The total input energy is significantly (four-times) higher in the wet season than in the dry season, mostly due to undue inflows (e.g., direct rainfall and infiltration). The potential for energy recovery strongly depends on the available head and flow rate at the delivery point, being 0.01 kWh/m3 in the current case, with a project payback period of 4 years. The energy balance components and the respective energy efficiency indices strongly depend on the considered reference elevation. Thus, a unique regional reference elevation is recommended in the calculations.

Validation of a 6-Dye Short Tandem Repeat System: A Dry Kit With Lyophilized Amplification Reagent

The SureID®S6 system used a lyophilized pellet as the amplification reagent to enable multiplexing of sex-determining marker Amelogenin, 21 autosomal short tandem repeats (STRs), and one Y-STR. To assess the performance, reliability, and limitation of the dry amplification system, the validation studies including PCR condition, reproducibility, sizing and precision, analytical threshold calculation, sensitivity and stochastic threshold calculation, species specificity, stability, mixture, case sample, and population and concordance were conducted according to the Scientific Working Group on DNA Analysis Methods (SWGDAM) Validation Guidelines. Experimental data suggested that the optimal range of total input DNA was from 125 to 500 pg; the appropriate analytical threshold was 80 relative fluorescence units (RFUs) while the stochastic threshold was 260 RFUs; for the stability studies, SureID®S6 system could resist against less than 500 μmol/L of hematin, 100 ng/μl of humic acid, 4 mM of indigotin, 800 mM of tannic acid, and 800 mM of calcium ion. Population and concordance studies using 500 unrelated individuals showed that the combined probability of discrimination (CPD) and cumulative probability of exclusion (CPE) values were 0.999999999999 and 0.999999998416, respectively. The genotypes for the same sample were concordant with the previously validated HUAXIA™ Platinum kit. The validation results demonstrated that the SureID®S6 system could be used for forensic applifications.

Evaluation of enterprise technology innovation capability in prefabricated construction in China

Purpose This study aims to evaluate enterprise technology innovation capability in prefabricated construction (PC) from an input-output perspective, using six integrated enterprises in China as cases. Design/methodology/approach An evaluation system for enterprise technology innovation capability in PC was constructed, including total input, technology output (TO) and project output. All the evaluation indexes were quantified, and the subject and object indexes weights were determined using the fuzzy cognitive map and information entropy, respectively. The final scores and ranks were evaluated through gray relational analysis (GRA) based on the combined weights. Findings It was found that enterprise technology innovation capability in PC was low in China, with its unbalanced development in different dimensions and the poorest performance in TO, currently. Originality/value This research has developed an evaluation system for technology innovation capability in PC at the enterprise level and scientifically quantified all the indexes, which is a breakthrough over existing studies. The GRA model based on the combined weights proposed in this study can be applied to other comparable fields and regions, with its easy operation.

Steric Effects on Space Electroosmotic Thrusters in Soft Nanochannels

The influence of steric effects on the performances of space electroosmotic thrusters (EOTs) was numerically delineated in soft nanochannels for which its walls are covered with polyelectrolyte materials. The size effect of the ionic species, namely the steric effect, is neglected in many previous research studies, but it has vital influences on electrostatic potential and electroosmotic velocity, which is further introduced into the present study in order to understand and improve the exploration of nano electroosmotic thrusters with soft channels. The thruster’s thrust, specific impulse, total input power, thruster efficiency and thrust-to-power ratio are computed based on finite difference methods. It is found that the thruster’s thrust and specific impulse increase with the steric parameter while the efficiency and thrust-to-power ratio possess opposite trends due to the enhancement of Joule heating dissipation. For real situations with the consideration of ion size, although the thruster’s thrust could be promoted, the efficiency is only 30–70%, and the peak values of thrust-to-power ratio fade away.

Tingkat Produktivitas Pada Aglomerasi Industri (Studi Kasus : Sentra Industri Mebel Tunjungsekar, Kota Malang)

Industri pengolahan non migas menjadi salah satu pilar perekonomian masyarakat Indonesia salah satunya adalah sektor Industri Kecil dan Menengah (IKM), IKM mampu menyerap tenaga kerja lebih dari 60% dari sektor industri, memiliki ketahanan akan kiris ekonomi dan juga berperan dalam ekonomi lokal, karena penyerapan tenaga kerja yang memanfaatkan masyarakat di sekitarnya. Industri pengolahan kayu menjadi salah satu industri yang berkembang pesat namun memiliki permasalahan terhadap ketersediaan bahan baku. Agar industri dapat terus berkompetisi salah satu strategi untuk efisiensi produksi dengan memanfaatkan industri yang beraglomerasi. Aglomerasi ini biasanya memunculkan manfaat ekonomi berupa limpahan tenaga kerja, kerja sama suplier khusus, terjadinya transfer pengetahuan dan teknologi, serta kerja sama pemasaran. Salah satu aglomerasi industri di Kota Malang ialah Industri Mebel Tunjungsekar. Produktivitas sentra industri mebel ini mengalami rintangan terutama pada persediaan bahan baku kayu dan tenaga kerja yang masih mengandalkan kekerabatan, selain itu ini belum didukung kelembagaan yang baik serta belum ada jaringan pemasaran yang kuat. Maka penelitian ini bertujuan untuk melihat bagaimana tingkat produktivitas sentra indutri mebel sebagai salah satu bentuk terjadinya aglomerasi menggunakan rumus produktivitas yaitu perbandingan nilai total output/ pendapatan dengan nilai total input/ pengeluaran (biaya tenaga kerja, modal dan bahan baku) di tahun 2019. Hasil analisis menunjukkan bahwa ke-30 industri mebel memiliki nilai di atas 1,0 dengan rata-rata nilai 1,31. Nilai produktivitas yang tidak jauh di atas 1,00 dikarenakan masih terdapat permasalahan pada tingginya biaya bahan baku dan modal namun tidak diimbangi dengan tingginya jumlah pesanan produk mebel yang terjual.

Energy Auditing of Cape Gooseberry (Physalis peruviana L.) Production with Agronomic Manipulations in Sodic Soils of Indo-gangetic Plains

This study investigated the energy input-output relationship in biomass production of cape gooseberry (Physalis peruviana L.) grown in Sodic soils of Indo-Gangetic plains with agronomic manipulations of plant spacing (90 x 75 cm, 75 x 75 cm, 75 x 75 cm) and NPK fertilizers (0, 60:40:40, 80:60:60, 100:80:80 N:P2O5:K2O kg ha-1). Results indicated that total input energy requirements in various treatments ranged from 16784.72 MJ ha-1 in 90 x 75 cm spacing without NPK fertilizers to 24395.04 MJ ha-1 in case of 75 x 60 cm spacing with NPK at 100:80:80 kg ha-1. Irrespective of agronomic manipulations, share of non-renewable energy in total input energy was very high (64.56%) and the percentage proportions of direct and indirect energies in the total input energy were 75.56 and 24.13%, respectively. Among various inputs, diesel accounted for the greatest proportion (40.44%) of total input energy, followed by water (32%), fertilizers (19.28%) and these three inputs constituted 92.08% of total input energy. Crop raised at 75 x 60 cm spacing with NPK at 100:80:80 kg ha-1 resulted the highest output energy (80863 MJ ha-1), net energy return (56529.91 MJ ha-1) and energy use efficiency (3.22); however, the results obtained at 75 x 60 cm spacing with NPK at 100:80:80 kg ha-1 were comparable. The best energy productivity (0.43) was achieved with 75 x 75 cm spacing and 100:80:80 kg NPK ha-1.