In this work, the design and the characterization of a broadband circular polarized monopole having low-profile and wide axial ratio beamwidth were presented. The antenna was designed on readily available, inexpensive glass-reinforced epoxy substrate having an overall size of 0.56λ0×0.50λ0×0.029λ0 (at center frequency 5.5 GHz). The proposed antenna was a modification of a square-shaped monopole antenna, which incorporates a pair of peripheral slits and an off-center slot for a elliptical polarized radiation. A v-shaped notch below the feed line was introduced and extended as antenna ground to generate broadband circular polarization characteristics. The −10 dB reflection coefficient bandwidth and 3-dB axial-ratio bandwidth of the proposed antenna were measured to be of 47.6 and 27 %, respectively. The 3-dB axial ratio beamwidth of the antenna was 93.5°. The antenna proposed in this work covers multiple application frequency bands including HiperLAN/2 IEEE 802.11a (5.15 - 5.35 GHz / 5.47 - 5.725 GHz) band, WLAN frequency band (5.1 - 5.9 GHz), C-band uplink (5.925 - 6.325 GHz) and part of military application band (4.75 - 4.99 GHz). HIGHLIGHTS Design and characterization of a broadband circular polarized monopole having low-profile and wide axial ratio beamwidth Proposed antenna covers multiple application frequency bands including HiperLAN/2 IEEE 802.11a, WLAN, C-band uplink and part of military application bands Proposed antenna is compact, low-profile and exhibits good polarization purity GRAPHICAL ABSTRACT
The present study was based on a participatory action research (PAR) design with the objectives of developing a participatory health care model for farmers and stakeholders involved in snakeskin gourami fish farming in Bang Bo District. The study was conducted from May 1, 2017 - April 30, 2018. The sample was composed of 85 people who were fish farmers, fish pond owners, and fish farming laborers involved in the processing and distribution of snakeskin gourami, 35 VHVs (village health volunteers), 1 registered nurse, and 1 administrator of a Tambon Health Promoting Hospital (THPH) for a total of 122 subjects. The PAR process involved 3 stages: Stage 1- Situation Analysis, Stage 2 - Participatory Action Research Process, and Stage 3 - Outcome Evaluation. The findings revealed 2 types of health problems: 1) work-related problems: incorrect work behaviors such as lifting heavy objects 1 - 5 times per day, repetitive work postures/positions causing aching bones and muscles and working fast to obtain large amounts and finish in time until work-related accidents occur such as knife cuts, pricked fingers from fish fins and slips/fallsand 2) Risks and illnesses caused by chronic disease. The synthesis of the participatory health care model disclosed that the health care activities covered 4 dimensions, encompassing health promotion, disease prevention, treatment, and recovery. The sample had a high level of satisfaction in the organization of the project at a mean of 4.40 of 5 points.
Vinegar is a liquid product produced from alcoholic and acetous fermentation. Vinegar contains acetic acid and bioactive compounds, which are brewed by liquid-state and solid-state fermentation techniques. This study reviews chemical fermentation process properties, bioactive compounds, and health benefits of fruit vinegars in Thailand. Chemical properties are the alcohol percentage and acetic acid percentage of vinegar. Bioactive compounds include antioxidant activity and total phenolic content, which have the role of antioxidative activity, blood pressure and glucose control, and anti-tumor. However, further studies are needed to find the new fruit raw materials to produce fruit vinegar which have more bioactive compound and more good taste.
Biogas upgraded to biomethane can be utilized as a renewable energy source to substitute LPG in households and industry. This study explored biogas upgrading by CO2 removal from 20 - 75 % CO2-N2 simulated biogas mixture. The experimental unit using the microbubble technique combined with the water absorption column was set up and used for CO2 removal from the gas. Microbubble sizes of 20 - 30 µm were generated by a venturi ejector and measured with an automated bubble size measurement. The experiments confirmed that a microbubble with an inline mixer could enhance the effectiveness of the absorption process. The tests demonstrated over 85.80 % removal of CO2 from the simulated biogas by the experimental unit. The effects of various parameters, including the size of venturi ejector, gas flow rate, water flow rate, liquid-gas ratio, and initial concentration of CO2, were investigated. The results revealed that 2 L/min gas flow rate, 15 L/min water flow rate, L/G ratio 7.5, and venturi ejector size 0.50 inches are the optimum conditions. The use of the tube absorber gave much higher CH4 recovery than an absorption column. The appropriate operating conditions gave over 96 % CH4 concentration or less than 4 % CO2 concentration, matching the CH4 purity required by biomethane specifications. The results indicated that the new technique demonstrated in this study can upgrade biogas to biomethane.
Tis study aimed to evaluate the embryo quality and embryo transfer rate of Thai crossbred goats fed different levels of protein in total mixed rations (TMR) during the hot season. Twenty-four non- pregnant Thai crossbred goats with an average body weight of 26±5.9 kg were assigned with a random complete block design (RCBD). Dietary treatments contained 8, 13, and 18 % crude protein (CP) in TMR. The feeding trial lasted for 42 days. Does (female goat) were scheduled to determine embryo quality by surgical laparotomy and flushing. At the end of the feeding trial, the digestion trial was conducted by the total collection method for a 5-day period. The results showed that the average total feed intake and feed conversion ratio did not differ among all treatments (p ˃ 0.05), however, digestible protein intake had increased from 70.39, 79.77 to 89.11 g/d in 8, 13, and 18 % CP group, respectively. Increasing CP levels in TMR resulted in linearly increased goat final body weight (30.25, 28.75, and 32.00 kg), weight gain (3.00, 4.00, and 4.25 kg), and average daily gain (ADG) (87.84, 114.87 and 121.63 g/d). Embryo quality (1, 1, and 3.5 morular follicle state) and pregnancy of embryo transfer rate (25, 25, and 50 %) of the animal received CP level at 8 and 13 % less than that 18 %. These results indicated that dietary protein level during program superovulation regimen affected the good quality of an embryo and the pregnancy rate in an embryo transfer in Thai crossbred goats.
