Estimating δ15N and δ13C in Barley and Pea Mixtures Using Near-Infrared Spectroscopy with Genetic Algorithm Based Partial Least Squares Regression

Stable isotope measurements have been increasingly used as a method to obtain information on relationships between plants and their environment (Dawson et al., 2002). Stable isotopes are seen as a powerful tool for advancing our knowledge on stock cycling and, nitrogen and carbon isotopic compositions have provided key insights into biogeochemical interactions between plants, soils and the atmosphere (Robinson, 2001). For the stable isotope measurements, the δ13C isotopic signature has been used successfully to disentangle physiological, ecological and biogeochemical processes and, δ15N studies have significantly improved our knowledge on nitrogen cycling pathways and nitrogen acquisition by plants (Vallano and Sparks, 2008). For the stable isotope measurements, traditional laboratory methods using isotope analysis are accurate and reliable, but usually time-consuming and expensive. Near-infrared spectroscopy (NIRS) analysis provides rapid, accurate and less expensive estimation. NIRS have been made to estimate herbage parameters using statistical methods such as multiple linear regression and partial least square regression (PLSR). PLSR uses all available wavebands in multivariate calibration for quantitative analysis of the spectral data. However, previous studies indicated that PLSR with waveband selection might improve their predictive accuracy in multivariate calibration at laboratory (Leardi, 2000) and the selection of appropriate wavelengths can refine the predictive accuracy of the PLS model by optimizing important spectral wavebands both in laboratory NIRS (Jiang et al., 2002). To optimize important spectral wavebands by wavelength selection, genetic algorithms (GA) is widely used, because GA has the ability to simulate the natural evolution of an individual and GA is well suited for solving variable subset selection problems (Ding et al., 1998). Barley and pea mixture is one of the most important forage species for livestock farming in Korea. To investigate nitrogen fixation and transfer in barley and pea mixture, stable isotope measurements was widely used. However, there was no research to estimate stable isotope in barley and pea mixture using NIRS in Korea. The aim of this study was to investigate performance of NIRS with PLSR using genetic algorithms based wavelength selection (GA-PLSR) and compare with PLSR without wavelength selection (FS-PLSR) for the estimation of δ15N and δ13C in barley and pea mixture

Special Apparel Needs of Consumers with Visual Impairments

The purpose of this study is to understand apparel consumers with visual impairments in terms of their apparel selection and shopping needs. The apparel needs of disabled consumers, specifically consumers with visual impairments, have not been thoroughly investigated (Chang et al., 2014). It is not known to what extent they differ, if at all, from consumers who are not visually impaired. Thus, this research provides insight into their apparel needs so that apparel manufacturers and retailers can better meet the needs of these disabled consumers

Effect of Phosphatic Fertilizer Rates Level on Growth, Crude Protein Content and Nitrogen Fixation Ability of Alfalfa at Sowing Year

The experiment was conducted to determine effects of phosphate fertilizers on growth characteristics, crude protein content and nitrogen fixation ability of alfalfa (Medicago sativa L) in the sowing year. Two rates of phosphate (200 and 400 kg/ha P) were applied to phosphorus -deficient native soil in Korea and samples were taken every 7 days from the 30th to the 93rd day. Number of branches, root length and dry matter weight at phosphate fertilizer level of 400kg in sowing year more increased than those at 200kg/ha. The number of nodules did not differ due to phosphate fertilizer rate. The crude protein contents of leaves, stems and roots were not significantly affected by the phosphate fertilizer levels, except for those of leaves with 400kg/ha at 72 days after sowing that were higher. The crude protein contents of each plant along the growing stages were higher at the 44th and 72nd day after sowing. The dry weight of roots did not significantly respond to phosphate rates from 30 days to 51 days after sowing, but that was increased at phosphate fertilizer level of 400kg/ha from 51 days after sowing. The amount of ethylene evolved by samples during 2 hours and the calculated amount of nitrogen fixed were higher on phosphate fertilizer level of 400kg/ha from 30 days to 58 days after sowing, but decreased that

Numerical Sensitivity Tests of Volatile Organic Compounds Emission to PM2.5 Formation during Heat Wave Period in 2018 in Two Southeast Korean Cities

A record-breaking severe heat wave was recorded in southeast Korea from 11 July to 15 August 2018, and the numerical sensitivity simulations of volatile organic compound (VOC) to secondarily generated particulate matter with diameter of less than 2.5 mu m (PM2.5) concentrations were studied in the Busan and Ulsan metropolitan areas in southeast Korea. A weather research and forecasting (WRF) model coupled with chemistry (WRF-Chem) was employed, and we carried out VOC emission sensitivity simulations to investigate variations in PM2.5 concentrations during the heat wave period that occurred from 11 July to 15 August 2018. In our study, when anthropogenic VOC emissions from the Comprehensive Regional Emissions Inventory for Atmospheric Transport Experiment-2015 (CREATE-2015) inventory were increased by approximately a factor of five in southeast Korea, a better agreement with observations of PM2.5 mass concentrations was simulated, implying an underestimation of anthropogenic VOC emissions over southeast Korea. The simulated secondary organic aerosol (SOA) fraction, in particular, showed greater dominance during high temperature periods such as 19-21 July, 2018, with the SOA fractions of 42.3% (in Busan) and 34.3% (in Ulsan) among a sub-total of seven inorganic and organic components. This is considerably higher than observed annual mean organic carbon (OC) fraction (28.4 +/- 4%) among seven components, indicating the enhancement of secondary organic aerosols induced by photochemical reactions during the heat wave period in both metropolitan areas. The PM2.5 to PM10 ratios were 0.69 and 0.74, on average, during the study period in the two cities. These were also significantly higher than the typical range in those cities, which was 0.5-0.6 in 2018. Our simulations implied that extremely high temperatures with no precipitation are significantly important to the secondary generation of PM2.5 with higher secondary organic aerosol fraction via photochemical reactions in southeastern Korean cities. Other possible relationships between anthropogenic VOC emissions and temperature during the heat wave episode are also discussed in this study

A new command shaping guidance law using Lagrange multiplier

This article presents a new command shaping guidance law by change of Lagrange multiplier (LM), called CSGL-LM. The Schwarz inequality approach is used to solve the optimal guidance problems considering both terminal constraints on interception and impact angle control. LM is introduced to combine two terminal constraints into a single equation. The main idea of this paper is to use LM as a design parameter for shaping the guidance command as well as controlling the terminal constraints. The guidance command of CSGL-LM is given a unified functional form of the time-to-go, the state variables, and LM. Therefore, through an appropriate choice of LM, we can achieve various shapes of the guidance commands for the interception case, as well as the impact angle control case. As illustrative examples, this paper also shows that a class of previous guidance laws is just one of particular solutions of CSGL-LM. Numerical simulations are performed to validate the properties of CSGL-LM, compared with the conventional guidance law

Effects of Temperature, Nitrgoen Fertilizer, and Cutting Height on Regrowth and Dry Matter Production

Orchardgrass (Dactylis glomerata L.) is used extentively in South Korea for green-chop and pasture mixtures. Maintaining orchardgrass stands over summer is a major problem in South Korea. Orchardgrass was grown in soil in growth chambers to evaluate the effect of temperature (day/night:20/JO, 27/17 and 3S/25°C), nitrogen (N) application (0, 5 and 10 kg/ha) and cutting height (5 and IO cm) on plant height, above­and below-ground dry matter yield, and leaf area accumulation. High temperatures (35/25°C) greatly reduced plant height, DM yields and leaf area expansion, Cutting to 10 cm gave greater DM yields and leaf areas, compared to cutting to 5 cm, but there were no differences between N fertiliser levels. High temperature is thought to be partially responsible for the commonly observed summer depression of orchardgrass growth and cutting to a greater height could improve DM yield and minimise stand losses during hot summers

Preparation of TiO2 nanotube/nanoparticle composite particles and their applications in dye-sensitized solar cells

Efficiency of dye-sensitized solar cells [DSSCs] was enhanced by combining the use of TiO2 nanotubes [TNTs] and nanoparticles. TNTs were fabricated by a sol-gel method, and TiO2 powders were produced through an alkali hydrothermal transformation. DSSCs were constructed using TNTs and TiO2 nanoparticles at various weight percentages. TNTs and TiO2 nanoparticles were coated onto FTO glass by the screen printing method. The DSSCs were fabricated using ruthenium(II) (N-719) and electrolyte (I3/I3-) dyes. The crystalline structure and morphology were characterized by X-ray diffraction and using a scanning electron microscope. The absorption spectra were measured using an UV-Vis spectrometer. The incident photocurrent conversion efficiency was measured using a solar simulator (100 mW/cm2). The DSSCs based on TNT/TiO2 nanoparticle hybrids showed better photovoltaic performance than cells made purely of TiO2 nanoparticles

EFFECTS OF MO, CR, AND V ADDITIONS ON TENSILE AND CHARPY IMPACT PROPERTIES OF API X80 PIPELINE STEELS

In this study, four API X80 pipeline steels were fabricated by varying Mo, Cr, and V additions, and their microstructures and crystallographic orientations were analyzed to investigate the effects of their alloying compositions on tensile properties and Charpy impact properties. Because additions of Mo and V promoted the formation of fine acicular ferrite (AF) and granular bainite (GB) while prohibiting the formation of coarse GB, they increased the strength and upper-shelf energy (USE) and decreased the energy transition temperature (ETT). The addition of Cr promoted the formation of coarse GB and hard secondary phases, thereby leading to an increased effective grain size, ETT, and strength, and a decreased USE. The addition of V resulted in a higher strength, a higher USE, a smaller effective grain size, and a lower ETT, because it promoted the formation of fine and homogeneous of AF and GB. The steel that contains 0.3 wt pct Mo and 0.06 wt pct V without Cr had the highest USE and the lowest ETT, because its microstructure was composed of fine AF and GB while its maintained excellent tensile properties.X1126sciescopu

Energy-optimal waypoint-following guidance considering autopilot dynamics

This paper addresses the problem of energy-optimal waypoint-following guidance for an Unmanned Aerial Vehicle with the consideration of a general autopilot dynamics model. The proposed guidance law is derived as a solution of a linear quadratic optimal control problem in conjunction with a linearized kinematics model. The algorithm developed integrates path planning and following into a single step and is able to be applied to a general waypoint-following mission. Theoretical analysis reveals that previously suggested optimal point-to-point guidance laws are special cases of the proposed approach. Nonlinear numerical simulations clearly demonstrate the effectiveness of the proposed formulations