An improved ant system algorithm for maximizing system reliability in the compatible module

This paper presents an improved Ant System (AS) algorithm called AS-2Swap for solving one of the reliability optimization problems. The objective is to selection a compatible module in order to maximize the system reliability and subject to budget constraints. This problem is NP-hard and formulated as a binary integer-programming problem with a nonlinear objective function. The proposed algorithm is based on the original AS algorithm and the improvement, focused on choosing the feasible solutions, neighborhood search with Swap technique for each loop of finding the solution. The implementation was tested by the five groups of data sets from the existing meta-heuristic found in the literature. The computational results show that the proposed algorithm can find the global optimal solution and is more accurate for larger problems

The development of a 10.7-MHz fully balanced current-tunable bandpass filter with Caprio technique

Bandpass filters are integral in modern communication systems for selecting specific frequency ranges to ensure interference-free signal transmission and reception. This paper explores various bandpass filter designs, including those using active inductors, transmission-line unit-cells, microstrip open-loop resonators, and dual-port dual-frequency integration antennas. The focus is on the 10.7-MHz bandpass filter, widely used in FM radio and television systems. The study evaluates current-controlled and balanced designs, analyzing their performance, advantages, and drawbacks. Unique trade-offs in terms of linearity, distortion, temperature sensitivity, and component variations are discussed. Additionally, advancements in filter technology and diverse design options are presented. The paper introduces a novel current-balanced, frequency-adjusted bandpass filter to address odd-order noise issues. This filter aims to achieve high linearity, harmonic distortion attenuation, and the elimination of even-order harmonics. Through synthesis, analysis, simulation, and comparison with traditional filters, the proposed design enhances signal quality and efficiency. The fully-balanced current-tunable bandpass filter with the Caprio technique at 10.7 MHz is developed, exhibiting symmetrical characteristics with lower total harmonic distortion. The circuit’s structure is simple and adaptable for integration, validated through consistent simulation results. The study concludes by emphasizing the constant sensitivity of transistor differential amplifier circuits to the center frequency and the linear relationship between center frequency and adjustable bias current. The suggested transistor and capacitor selection criteria contribute to optimizing the circuit’s performance, aligning with the Caprio technique’s recommendations. Overall, this research presents a promising solution for achieving high-quality signal transmission in contemporary communication system

ระบบวัดแรงกดของเครื่องกดชิ้นงานแบบเวลาจริงด้วยตัวตรวจจับแรงดันในกระบอกสูบ Real-time Force Measurement System of the Pressing Machine with a Pressure Sensor in the Cylinder

บทความวิจัยนี้นำเสนอระบบการวัดแรงกดของเครื่องกดชิ้นงานแบบเวลาจริงด้วยตัวตรวจจับแรงดันในกระบอกสูบ ซึ่งเป็นวิธีการวัดแรงกดทางอ้อมด้วยตัวตรวจจับแรงดันในกระบอกสูบ โดยทำการวัดความดันอากาศในกระบอกสูบและวัดค่าแรงดันไฟฟ้าของตัวตรวจจับแรงดันในกระบอกสูบ จากนั้น นำค่าแรงดันไฟฟ้าที่วัดได้ไปเปลี่ยนเป็นแรงกดด้วยสมการที่ได้จากการทดลอง ข้อดีของการวัดแรงกดด้วยวิธีการดังกล่าวคือ ทำให้ลดเวลาที่สูญเสียในกระบวนการผลิต ส่งผลให้สามารถเพิ่มผลผลิตได้มากขึ้น ผลการทดลองวัดแรงกดเปรียบเทียบกับเครื่องวัดแรงกดอ้างอิงพบว่า เมื่อทำการทดลองวัดแรงกดด้วยอุปกรณ์วัดแรงกดที่พัฒนาขึ้นเปรียบเทียบกับโหลดเซลล์ที่เครื่องกดแบตเตอรี่ มีความคลาดเคลื่อนจากโหลดเซลล์ต่ำสุดอยู่ที่ 0.010 เปอร์เซ็นต์ และค่าความคลาดเคลื่อนสูงสุดอยู่ที่ 0.687 เปอร์เซ็นต์ นอกจากนั้นผลการทดลองที่เครื่องกดจุดเชื่อมต่อ PCB พบว่ามีความคลาดเคลื่อนจากโหลดเซลล์ต่ำสุดอยู่ที่ 0.043 เปอร์เซ็นต์ และค่าความคลาดเคลื่อนสูงสุดอยู่ที่ 1.768 เปอร์เซ็นต์ ในส่วนของการแสดงผลระบบได้แสดงผลการวัดแรงกดผ่านเว็บไซต์ที่ถูกพัฒนาขึ้นมาด้วยภาษา PHP HTML JavaScript และ Ajax ผลการทดสอบแสดงให้เห็นว่า ระบบที่พัฒนาขึ้นสามารถวัดแรงกดได้ใกล้เคียงกับอุปกรณ์ที่ใช้อ้างอิง (โหลดเซลล์) รวมทั้งสามารถวัดและแสดงผลแบบเวลาจริงได้This paper presents a real-time force measurement system of the pressing machine with a pressure sensor in the cylinder. It is an indirect measurement method of force with a pressure sensor in the cylinder. The air pressure is measured in the cylinder and also the voltage of the pressure sensor is measured. After that, the measured voltage is transformed into force by the equation from the experiments. The advantage of this method is that it can reduce the wasting time in the production process, resulting in increased productivity. The results of the force measurement comparing with the reference device (load cell) showed that performing force measurement experiments using the developed system compared to that of the load cells (reference device) at the battery pressing machine. The minimum error is 0.010% and the maximum error is 0.687%. Moreover, the results from the PCB connection pressing machine found that the minimum error is 0.043% and the maximum error is 1.768%. For the monitoring of the real-time force, the system showed the results of the force measurement in the website developed using PHP, HTML, JavaScript and Ajax. The results showed that the measured forces obtained the developed system were close to the measured force from the reference device (load cell) and it could measure and display the results in real-time.Keywordsวัดแรงกด; เวลาจริง; เซ็นเซอร์วัดความดันอากาศ; พีเอชพี; เอชทีเอ็มแอลForce Measurement; Real-Time; Pressure Sensor; PHP; HTM

Determination of Relationship between Dielectric Properties, Compressive Strength, and Age of Concrete with Rice Husk Ash Using Planar Coaxial Probe

This paper deals with an investigation of the dielectric properties of concretes that includes rice husk ash using a planar coaxial probe. The planar coaxial probe has a planar structure with a microstrip and coaxial features. The measurement was performed over the frequency range of 0.5-3.5 GHz, and concrete specimens with different percentages of rice husk ash were tested. The results indicated that the dielectric constant of the concretes was inversely proportional to the frequency, while the conductivity was proportional to the frequency. The dielectric constant decreased with the increasing age of the concrete at the frequency of 1 GHz. The conductivity of the concrete decreased with the increasing age of the concrete at the frequency of 3.2 GHz. In addition, the dielectric constant and the conductivity decreased when the compressive strength increased. It was also shown that the obtained dielectric properties of the concrete could be used to investigate the relationship between the compressive strength and age of the concrete. Moreover, there is an opportunity to apply the proposed probe to determine the dielectric properties of other materials

Design of a Compact Ultra-Wideband Bandpass Filter Using Inductively Compensated Parallel-Coupled Lines

An ultra-wideband bandpass filter (UWB-BPF) using inductively compensated parallel-coupled lines (ICPCL) is presented in this article. It consists of three circuits: a high-pass filter (HPF), a lowpass filter (LPF), and a transmission line. The HPF and the LPF are independently synthesized from the ICPCL. The proposed filter can suppress unwanted frequencies in the upper stopband and increase the skirt slope of the frequency response in the transition bands. The fabricated UWB-BPF with compact size provides good passband performances, with insertion loss of better than −0.49 dB and return loss of better than −12 dB in the frequency range of 2.92–10.95 GHz (the bandwidth of 8.03 GHz). The 107% bandwidth is achieved. In addition, the proposed filter can suppress the spurious frequencies at 2f0, which is greater than 30 dB. The measured results accord well with the simulation results. The novelty of the paper is the introduction of the ICPCL for the construction of the compact UWB-BPF

Design and Fabrication of Modified SMA-Connector Sensor for Detecting Water Adulteration in Honey and Natural Latex

A detection system for water adulteration in honey is proposed. It consists of a modified SMA-connector sensor and a vector network analyzer. A modified SMA-connector sensor is applied to measure complex relative permittivity, electrical conductivity, and phase constant of honey samples with the open-ended method. The system is tested in the frequency range of 0.5–4.0 GHz at the sample temperature of 25 °C. The relationships between the complex relative permittivity, electrical conductivity, the phase constant, and the honey samples with different concentrations (0–30%w/w) are determined. The experimental results show that the real part of the complex relative permittivity is significantly proportional in honey samples with adulteration of water in the range of 0–30%w/w. The frequency of 0.6 GHz is a suitable frequency for detection with a real part of complex relative permittivity as an indicator. The frequency of 3.74 GHz is an appropriate frequency for detection with electrical conductivity as in indicator while the frequency of 4.0 GHz is suitable for detection with phase constant as an indicator. In addition, the data are analyzed with regression analysis. This technique is also performed on natural latex samples to determine the dry rubber content. The frequency of 0.5 GHz is a suitable frequency with a real part of complex relative permittivity as an indicator while the frequency of 4.0 GHz is a suitable frequency with an imaginary part of complex relative permittivity, electrical conductivity, and phase constant as the indicators. The results demonstrate that it is possible to apply this technique to determine the dry rubber content in the natural latex samples as well

Design and Fabrication of Modified SMA-Connector Sensor for Detecting Water Adulteration in Honey and Natural Latex

A detection system for water adulteration in honey is proposed. It consists of a modified SMA-connector sensor and a vector network analyzer. A modified SMA-connector sensor is applied to measure complex relative permittivity, electrical conductivity, and phase constant of honey samples with the open-ended method. The system is tested in the frequency range of 0.5–4.0 GHz at the sample temperature of 25 °C. The relationships between the complex relative permittivity, electrical conductivity, the phase constant, and the honey samples with different concentrations (0–30%w/w) are determined. The experimental results show that the real part of the complex relative permittivity is significantly proportional in honey samples with adulteration of water in the range of 0–30%w/w. The frequency of 0.6 GHz is a suitable frequency for detection with a real part of complex relative permittivity as an indicator. The frequency of 3.74 GHz is an appropriate frequency for detection with electrical conductivity as in indicator while the frequency of 4.0 GHz is suitable for detection with phase constant as an indicator. In addition, the data are analyzed with regression analysis. This technique is also performed on natural latex samples to determine the dry rubber content. The frequency of 0.5 GHz is a suitable frequency with a real part of complex relative permittivity as an indicator while the frequency of 4.0 GHz is a suitable frequency with an imaginary part of complex relative permittivity, electrical conductivity, and phase constant as the indicators. The results demonstrate that it is possible to apply this technique to determine the dry rubber content in the natural latex samples as well