Conventional Ring Research Articles

Investigation of Yarn Quality in Ring Yarn by Modifying Bottom Apron/Nose Bar with Perforations and Air-Suction

Currently, ring spinning has limitations of poor integration of fibers that protrude from yarn surface, which causes hairiness and irregularity. The aim of this research is to improve yarn quality by modification of bottom apron/nose bar with perforation and applying air-suction in a conventional Reiter G35 ring frame and spinning 29.52 Tex (20 Ne) and 14.76 Tex (40 Ne). To produce modified yarn 17 combinations of apron hole diameter, suction pressure, and widthwise hole distance was used. The ANOVA result shows that as suction pressure increases hairiness, tenacity, and thick place (+50%/km) were improved significantly for both counts. Based on the result suction pressure, apron hole diameter, and hole distance were optimized to 23.9 mbar, 1.58 mm and 10 mm respectively for 40 Ne and 25 mbar, 1.75 mm, and 11.6 mm respectively for 20 Ne. As compared with conventional hairiness, tenacity, thin place, and thick place of 40 Ne modified yarn were improved by 16.25%, 12.7%, 17.42%, and 14.62% respectively. Whereas hairiness, tenacity, and thick place of 20 Ne modified yarn were improved by 8.87%, 7.42%, and 18.2% respectively. Thus, the modified G35 method of yarn condensing has capability to be used as an alternative method of conventional spinning as it is capable of producing better quality yarn.

Enhanced rotation sensing and exceptional points in a parity-time-symmetric coupled-ring gyroscope.

Enhancement in rotation sensitivity is achieved in a parity-time-symmetric gyroscope consisting of a ring with gain coupled to a lossy ring, operated below laser threshold and in the vicinity of its exceptional point (EP). An external laser and a conventional readout system are used to measure the large rotation-induced shifts in resonance frequency known to occur in this device. A complete model of the rotation sensitivity is derived that accounts for gain saturation caused by the large circulating power. Compared to a single-ring gyro, the sensitivity is enhanced by a factor of ∼300 when the inter-ring coupling is tuned to its EP value κEP, and ∼2400 when it is decreased from κEP, even though the Sagnac frequency shift is then much smaller. ∼40% of this 2400-fold enhancement is assigned to a new sensing mechanism where rotation alters the gain saturation. These results show that this compact gyro has a far greater sensitivity than a conventional ring gyro, and that this improvement arises mostly from the gain compensating the loss, as opposed to the enhanced Sagnac frequency shift from the EP. This gyro is also shown to be much more stable against gain fluctuations than a single-ring gyro with gain.

Precision Manufacturing of a Linear Fiber Assembly with Axially Varying Compositions and Structures by Using Computer Numerically Controlled Ring Spinning

Ring spinning is an effective technology for forming multi-component spun yarns. There is an increasing need for multifunctional textiles with characteristics, such as antibacterial properties, UV protection, easy cleaning, and color alteration, which can be achieved via various physical and mechanical processing approaches, such as electrospinning, friction spinning, hollow spindle spinning, and ring spinning. In particular, ring spinning is based on the mechanical processing of fibers, and it is suitable for mass customized production systems. However, conventional ring spinning involves a fixed fiber blending ratio and yarn linear density, which limits its usefulness for fabricating multifunctional textiles due to the uncontrollable composite yarn structure. In the present work, we propose a new method for manufacturing a three-component spun yarn by combining a computer numerical control system with a ring spinning frame, which increases the flexibility of yarn production. The as-prepared composite yarns possess axially varying compositions and structures, which can be readily tuned by changing the feeding speeds of the back rollers, and these aspects can facilitate the fabrication of multifunctional textiles for mass production at a low cost. To the best of our knowledge, this is the first work to demonstrate the feasibility of fabricating a three-component spun yarn with tunable compositions and structures by employing a ring spinning frame.

Design Principles for a Novel Lightweight Configurable PUF Using a Reconfigurable FET

This article presents a mixed signal-based novel configurable ring oscillator (CRO) physical unclonable function (PUF) architecture for resource constrained Internet of Things (IoT) devices. PUF can protect the IoT devices through their unique inherited fingerprints obtained from the manufacture variations. However, the conventional ring oscillator (RO) PUF need multiple replicas of ROs to produce a large set of challenge response pairs (CRPs) which invalidates its usage in an IoT environment. Using the concept of reconfigurable hetero material hetero dielectric FET (HM-HD-RFET) proposed in this manuscript, we have designed a novel CRO which allows 512 challenges and a sigma delta analog to digital converter (ADC) at the end generates a stream of response bits. HM-HD-RFET can be configured into four different combinations of transistors through two polarity gates (PGs) and their switching can be controlled using a control gate (CG). Next, we compare HM-HD-RFET with configurable silicon FET (Si-RFET) and homogenous dielectric FET (HM-RFET) to show that the proposed device performs well in all of the four configurations with negligible ambipolarity. The device characteristics is realized in Silvaco Atlas tool, circuit implementation is done in Cadence using Verilog-A based look table approach and properties of CRO PUF are computed in MATLAB.

A simple electrically small microwave sensor based on complementary asymmetric single split resonator for dielectric characterization of solids and liquids

The article presents an asymmetric single split resonator (ASSR) unit cell, its resonant properties, and an electrically small microwave sensor employing the complementary asymmetric single split resonator (CASSR) structure with high quality factor (Q) on the FR4 substrate. The structure is compared with the conventional symmetric split ring resonator. The CASSR sensor designed and fabricated on a substrate of dielectric constant 4.4 and a thickness 1.6 mm has an electrically small size of 0.127λ0 × 0.127λ0 × 0.007λ0 at 1.27 GHz, which yields ka = 0.56 < 1 with low radiation efficiency. The properties and performance of the proposed CASSR for extracting the permittivity of both solid and liquid samples using amplitude and phase sensing in a simple lab-in-touch approach are validated with full-wave simulations and experimental results.

Numerical Investigation of All-Optical Manipulation for Polarization-Multiplexed Cavity Solitons

Temporal cavity solitons (CSs) are pulses that can maintain their shape and circulate indefinitely in a resonant cavity under coherent driving. The approach for writing, erasing, and moving of CSs have significant ramifications for optical signal processing such as buffering. Previous work mainly focused on the manipulation of scalar CSs while conventional macroscopic fiber ring cavity usually supports two polarization states simultaneously. Exploring the CSs manipulation for both one is of great significance for today's polarization-multiplexed systems. In this article, the all-optical CSs manipulation associated with two orthogonal polarizations in a monochromatically driven Kerr resonator is investigated. Based on the vectorial mean-field Lugiato–Lefever equations, we theoretically demonstrate the independent writing, erasing, and moving of polarization-multiplexed CSs through intensity-modulation- or phase-modulation-induced perturbation. The results can be useful guidance for high-speed and high capacity information processing.

Comparison between Conventional Ring and Compact Spinning of some Egyptian Cotton Varieties

The current experiments was conducted at Plant Production Department, Faculty of Agriculture (Saba-Basha) Alexandria University, during 2019 season to evaluate the fiber and yarn properties of combed yarns by compact and conventional ring spun yarns for three Egyptian cotton varieties (Giza 94, Giza 92 and Giza 86) which belong to long staple category under three yarn count (Ne 80’s, Ne 100’s and Ne 120’s). The fiber properties were measured as well as yarn properties by two spinning system were made at Cotton Research Institute under comparable technological condition on RstI Marzoli ring and compact spinning fitted with Olfil system on one frame. The results showed that the compact spinning surpassed than conventional ring spinning in yarn traits i.e. lea count strength product (LCSP), single yarn strength (cN/tex), elongation (%), CV%, thin and thick places, neps, total imperfections and yarn hairiness. as that the compact spinning recorded the higher desirable values for lea count strength product (LCSP) (2900), single yarn strength (cN/tex) (25.39) and elongation (%) (5.03). as recorded the lower desirable values for CV%, thin (16) and thick places (36), neps (68), total imperfections (120) and yarn hairiness (1.60). As well as cotton variety Giza 92 recorded the desirable values for lea count strength product (LCSP) (3030), single yarn strength (cN/tex) (25.24) and CV% (12.08). On the other side, Giza 86 recorded the better values for thin (11) and thick places (21), neps (67), total imperfections (99) and yarn hairiness (1.80). Yarn count Ne 80’s gave the desirable values for above studied traits. The first order and second order interaction were significant differences for all studied traits. From the previous results it could be say that cotton variety Giza 92 under both compact spinning and Ne 80’s recorded the best values for the studied characters. In general, the properties of combed yarns produced with compact spinning system are better than the those with conventional ring spinning system, compact yarns were having better tensile properties, elongation ratio and lower hairiness than conventional ring yarns, that could be due to the elimination of spinning triangle in spinning system, and the decrease from the flight of fibers of structure yarn increase and this leads to higher yarn tenacity and elongation ratio. Also, Compact spun combed yarn was to found to have higher evenness and lower number of total imperfection values (thin places, thick places and neps). If the evenness property of compact yarn can be improved, it will have a potential for improving quality and profitability of cotton yarn manufacturing.

Simulation of mechanical stresses in reinforced REBaCuO ring bulks during pulsed-field magnetization

We have performed numerical simulations of the electromagnetic, thermal and mechanical properties of a REBaCuO ring-shaped bulk with various reinforcement structures during pulsed-field magnetization (PFM). Compressive and tensile electromagnetic stresses, , are developed in the ring-shaped bulk during the ascending and descending stages of PFM, respectively. These stresses increase at lower operating temperatures and for higher applied pulsed fields. In order to reduce these stresses, the ring-shaped bulk was fully encapsulated by outer and inner ring with upper and lower plates made by Al alloy. In particular, this reinforcement structure can achieve the lowest electromagnetic compressive stress, which corresponds to about 54% of that for a conventional ring reinforcement structure, and the electromagnetic tensile stress was also reduced. We also compared the simulation results of the electromagnetic stresses for the ring-shaped bulk to those for a disk-shaped bulk.

Enhanced toroidal localized spoof surface plasmons in homolateral double-split ring resonators.

In this paper, toroidal localized spoof surface plasmons (LSSPs) based on homolateral double-split ring resonators is proposed and experimentally demonstrated at microwave frequencies. By introducing a new split in the conventional single-split ring resonator, the magnetic field in resonator is locally modified. The double-split ring resonator can create the mixed coupling in the structure, leading to the enhancement of magnetic field. Both numerical simulations and experiments are in good agreement. Compared with traditional toroidal LSSPs based on the single-split ring resonators, the imperfection of toroidal LSSPs is resolved, the intensity of toroidal resonance and the figure of merit (FoM) are significantly enhanced. To understand and clarify the enhanced magnetic field phenomena, we analyze the role of the double-split ring resonator. The effect of location of source and spacing between two splits on the resonance intensity are also discussed. A higher intensity of toroidal LSSPs resonance could be achieved by changing the spacing between two splits. Additionally, it is experimentally demonstrated that the enhanced toroidal LSSPs resonance is sensitivity to the background medium. The results of our research provide a new idea for exciting the enhanced toroidal dipole.

Non-Contacting Finger Seal Piston for Oil Less Engines

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;The current quest to reduce CO&lt;sub&gt;2&lt;/sub&gt; emissions combined to new technologies has sparked an interest in revisiting radically different engine configuration concepts, such as adiabatic and split-cycle engines. To achieve the full potential of both concepts, the combustion chamber must be sealed without lubricating oil. A promising approach that has yet remained elusive, is to lubricate the piston-liner interface with gases. This paper explores the concept of using non-contacting finger seals to seal piston engines combustion chambers. The finger seals, made of a gas-lubricated pad at the end of a flexible beam, are fixed on a rotating piston that uses the centrifugal force to close the piston-liner gap. A physics-based fluid-structure model is developed to predict finger displacements and sealing performances. The model shows that the radial displacement of the fingers naturally creates a convergent profile with the liner that generates sufficient aerodynamic pressure to maintain a micrometer gap that prevents the piston to contact the liner. The results also show that the achievable leakage area would be similar to that of Wankel rotary engine and friction losses would be negligible compared to those of conventional piston rings. On the other hand, the study reveals challenges that will need to be addressed in order that finger seals be practical in engines, such as the finger torsion, dynamic behavior when exposed to bore distortion as well as the manufacturing tolerances required to ensure contact-free operation.&lt;/div&gt;&lt;/div&gt;

Design of a segment-type ring burst test device to evaluate the pressure resistance performance of composite pressure vessels

Composite pressure vessels used to store fuel gases or liquids should exhibit mechanical properties that allow them to withstand high pressures without being damaged. Therefore, an accurate measurement of their mechanical properties is essential prior to their commercial release. A segment-type ring burst test is a facile method to determine the burst pressure; however, the application of uniform pressure to the specimen remains a crucial issue to be addressed. Therefore, in this study, the conventional ring burst test device is modified to enhance the uniformity of pressure applied to the specimen. First, the equation of load transfer ratio from the applied load is derived. To verify the uniformity of pressure in the ring burst test device, the hoop strain distribution of the ring specimen is compared with that of the hydraulic pressure test obtained from the theoretical equation and finite element analysis. Based on the result, the number of segments is determined, and a polytetrafluoroethylene sheet is placed between the segments and the specimen to reduce the discrepancy of the hoop strain. Furthermore, to verify the reliability of the redesigned test device, the strain distribution and fracture behavior are assessed using the digital image correlation method and a high-speed camera.

Modified Ring Power Divider Using Stepped-Impedance Resonator

In this paper, the design of a modified ring power divider dedicated for wideband communication or measurement systems is presented. The proposed power divider is built by using a conventional ring power divider and an additional Stepped-Impedance Resonator (SIR). The even-odd mode analysis is used to derive the design equations. In order to observe the bandwidth improvement, a comparative study between the designed device and the previously reported ring power divider is conducted. The electromagnetic (EM) simulated results show that the proposed divider has a fractional bandwidth of 90.2 % at the center frequency of 3.17 GHz and shows a bandwidth enhancement up to 27.2 % compared to the conventional ring structure. The measurement results of the fabricated prototype demonstrate high performance over the considered operational bandwidth from 1.7 GHz to 4.64 GHz with a return loss lower than -10 dB while maintaining a good insertion loss and a good isolation between the output ports. The maximum amplitude imbalance is better than 0.21 dB and the phase imbalance is better than 2.5 degrees between the output signals. The simulation and measurement results are in good agreement over the whole band of interest.

Effects of nozzle structural parameters on yarn hairiness in jetring spinning system

In this study, the effects of the performance of air nozzles called jetring, which can be connected to a conventional ring spinning machine, over the yarn hairiness values were investigated. To determine the lowest yarn hairiness value, experimental and statistical studies were carried out on various nozzle structural parameters. The response surface methodology was used to optimize the yarn hairiness value. In the experiment, 100% cotton Ne 30/1 yarns were produced. In all jetring yarn productions, the air pressure was kept at 125 kPa (gauge). Hairiness results were analyzed using ANOVA in the Design Expert 11.0 program. Nozzle structural configuration that provided the lowest yarn hairiness according to the statistical model was as follows: twisting chamber diameter Ø2 mm, injector diameter Ø0.5 mm and injector angle 35° as determined. Ne 30/1 100% cotton yarns produced with this nozzle structural configuration, yarn hairiness values were reduced by 12%.

A novel miniaturized asymmetric CPW split ring resonator with extended field distribution pattern for sensing applications

Novel modified split-ring resonator (SRR) for expanded field distribution and miniaturized dimensions for sensing with double sided detection capability is proposed. The proposed design is based on an asymmetric coplanar waveguide type SRR and demonstrate a smaller radius of 0.035 × λ with a resonance of 1.57 GHz at its first harmonic. The proposed structure has the potential of higher sensitivity, requires smaller sample volume and is miniaturized compared to the conventional ring resonators. The long but narrow overlap gaps evident in the proposed miniaturized SRR create capacitive and inductive contributions for better sensing performance regime and optimized for superior efficiency and miniaturization capability. For sensitivity evaluation, a coplanar SRR prototype operating at the same resonance is compared with the proposed miniaturized coplanar SRR to underscore its superior performance profile. The resulting design is prototyped on RO3003 microwave laminate with dielectric permittivity (ℇr) of 3 and measured. Sensitivity analysis is conducted by loading the both resonator on both planes with Teflon cladding sample of permittivity of 2.33, thickness of 3 mm and the results are compared. The final design is validated by loading the proposed resonator with a 0.05λ × 0.05λ sq.m and a strip of 0.045λ × 0.015λ sq.m moisture-responsive commercially available 3 M transparent water-soluble wave solder tape 5414 Poly-vinyl alcohol (PVA) film having a thickness of 20 μm.

An experimental verification on existence of air-drag force influencing yarn tension during rotor spinning

PurposeMost researchers have neglected the effect air-drag force on yarn tension during rotor spinning. This paper aims to study the effect of rotor air-vacuum pressure in conjunction with opening roller speed and yarn linear density on the yarn tension generated during the rotor spinning, which has established their significant influences on both the mean and the peak tension.This is the first of one-of-a-kind experimental study being reported to demonstrate the influence of air-drag force on yarn tension during the rotor spinning under dynamic condition.Design/methodology/approachThe dynamic measurements on yarn tension at the exit of the doffing tube were carried out by using an electronic capacitive yarn tension meter during rotor spinning. The derived experimental data were fitted into equations to construct the response equations and to work out the coefficients of multiple correlation between the data and the predicted equation for both the mean and the peak tension. Various surface plots were constructed by using those response surface equations, so as to study the effect of variables on yarn tension generated during the rotor spinning.FindingsThe study has established that the rotor vacuum is responsible in causing a change in yarn tension, it increases with the decrease in air-vacuum inside the rotor. The involvement of the opening roller speed in altering yarn tension during rotor spinning has been proved. As the opening roller speed changes, so does the air stream surrounding the opening roller speed with consequent alteration of the centrifugal force generated due to the rotation of the rotor. The centrifugal force and, hence, the yarn tension generated in the rotor will be simultaneously affected by both the rotor relative vacuum and the opening roller speed.Research limitations/implicationsThis is a structured experimental study to verify the influence of air-drag force generated during rotor spinning on yarn tension. Very limited theoretical work has been carried out in this direction as reported in the introductory part of the paper. The result of the present study will encourage future researchers to revisit the theory on generation of air-drag force during rotor spinning and work out a new formula.Practical implicationsNext only to the conventional ring spinning system, the rotor spinning holds the second place in the share of global yarn production. Because of its advantage of lower cost of production and amenability to automation, the rotor spinning has gained acceptance in spun yarn production, particularly for spinning coarse and medium counts of yarns. Currently, it has acquired about 25 per cent share in the world’s spun yarn production. As many of the rotor machine variables significantly affect fibre configurations and, subsequently, the yarn properties by influencing the airflow characteristics inside the rotor unit, the study of yarn tension during rotor spinning and its analysis assumes a significance.Social implicationsRotor spinning is a relatively new and faster method of conversion of discrete fibres into continuous staple yarn and, subsequently, various textiles and garments. Its yarn is distinct and a bit different compared to the conventional ring yarn. It has got wide acceptance in the market and fashion. As such, the spinning sector that converts fibres into yarns is an important industry world over, providing employment to many. Besides, being the basic operation in the fibre value chain, it supports many downstream activities, including human clothing and fashion. Thus, the research on rotor spinning, particularly the yarn engineering to produce better products will be helpful to strengthen and grow the textile value chain.Originality/valueThis is an original research study. The magnitude and the direction of the air drag on the yarn during rotor spinning is very difficult to assess. Thus, most researchers for the sake of simplicity in analysis have neglected its effect on yarn dynamics, but a few of them have taken note of it in their theoretical propositions. However, no experimental result has been reported so far in the literature, supporting the influence of such air-drag force on yarn tension in the rotor spinning. In fact, none of the above studies have considered the induced effect of centrifugal force caused because of the rotation of the opening roller on the airstream that flows from the transfer channel inlet into the rotor because of its partial vacuum, causing consequential effects on air-drag force and tension in the yarn inside the rotating rotor. This is the first of one-of-a-kind experimental study being reported to demonstrate the influence of air-drag force on yarn tension during the rotor spinning under dynamic condition.

The value of hybrid interstitial tandem and ring applicators for organ at risk dose reduction in small volume cervical cancer.

PurposeMagnetic resonance imaging (MRI)-guided adaptive brachytherapy is the standard of care for cervical cancer. Hybrid intracavitary/interstitial applicators for bulky tumor (high-risk clinical target volume [HR-CTV] > 30 cc) dose escalation is recommended in the EMBRACE II trial. The value of hybrid applicators for smaller HR-CTV (< 30 cc) in organ at risk (OAR) sparing is less certain.Material and methodsTwenty-seven patients with FIGO stage I-IVA cervical cancer treated with definitive chemoradiation and MRI-based brachytherapy using conventional tandem and ring (TR) applicators were re-planned using virtual needles. They were then summed with the external beam dose to evaluate target coverage and OAR dose using EQD2 summation. Target and OAR dose with/without hybrid applicator use were compared.ResultsEighty-one percent had HR-CTV volumes < 30 cc, for which, hybrid TR applicators had significantly lower mean D2cc to all OARs without differences in target coverage. For HR-CTV < 30 cc, the bladder and rectal OAR goals per EMBRACE II were exceeded in significantly fewer patients with the hybrid TR applicators. No significant difference was found in the sigmoid D2cc dose goal.ConclusionsIn small volume tumors (< 30 cc), hybrid applicators may offer improved OAR sparing compared with conventional tandem and ring applicators, and may increase the proportion of patients meeting EMBRACE II OAR goals.

Monitoring innate immune cell dynamics in the glioma microenvironment by magnetic resonance imaging and multiphoton microscopy (MR-MPM).

Rationale: Glioblastoma is the most frequent, primary brain tumor that is characterized by a highly immunosuppressive tumor microenvironment (TME). The TME plays a key role for tumor biology and the effectiveness of immunotherapies. Composition of the TME correlates with overall survival and governs therapy response. Non invasive assessment of the TME has been notoriously difficult. Methods: We have designed an in vivo imaging approach to non invasively visualize innate immune cell dynamics in the TME in a mouse glioma model by correlated MRI and multiphoton microscopy (MR-MPM) using a bimodal, fluorescently labeled iron oxide nanoparticle (NP). The introduction of Teflon cranial windows instead of conventional Titanium rings dramatically reduced susceptibility artifacts on MRI and allowed longitudinal MR-MPM imaging for innate immune cell tracking in the same animal. Results: We visualized tumor associated macrophage and microglia (TAM) dynamics in the TME and dissect the single steps of NP uptake by blood-born monocytes that give rise to tumor-associated macrophages. Next to peripheral NP-loading, we identified a second route of direct nanoparticle uptake via the disrupted blood-brain barrier to directly label tissue resident TAMs. Conclusion: Our approach allows innate immune cell tracking by MRI and multiphoton microscopy in the same animal to longitudinally investigate innate immune cell dynamics in the TME.

Lightweight Configurable Ring Oscillator PUF Based on RRAM/CMOS Hybrid Circuits

Physical unclonable function (PUF) is a lightweight security primitive for energy constrained digital systems. As an enhanced design of conventional ring oscillator (RO) PUFs, configurable ring oscillator (CRO) PUFs improve the uniqueness and reliability compared with the conventional RO PUF designs. In typical CRO PUF designs, multiplexers (MUXs) are utilized as configurable components. In this paper, a hybrid nano-scale CRO ( $hn$ -CRO) PUF is proposed. The configurable components of the proposed $hn$ -CRO PUF are implemented by RRAMs. The delay elements are based on CMOS inverters. Compared with traditional CRO PUF designs, the proposed $hn$ -CRO PUF is cost-efficient in terms of circuit density and gate per challenge response pair (CRP) bit. To validate the proposed $hn$ -CRO PUF, the Monte Carlo simulation results of a compact RRAM model under UMC 65 nm technology are presented. The results show that the proposed $hn$ -CRO PUF has a good uniqueness and low hardware consumption compared with the previous works.

KONVANSİYONEL RİNG VE YENİ BİR MODİFİYE RİNG İPLİK EĞİRME SİSTEMİ KULLANILARAK ÜRETİLEN İPLİK VE KUMAŞLARIN BAZI ÖZELLİKLERİNİN KARŞILAŞTIRILMASI

In this study, it is aimed to evaluate the properties of the yarns produced by conventional ring and a new modified ring (ProSPIN®) spinning system developed to solve the problems arising from the spinning triangle and the knitted fabrics obtained from these yarns by comparison. For this purpose, the equivalent ring and ProSPIN yarns with yarn counts Ne 20 and Ne 28 and twist coefficients αe 3,5 and αe 4,1 were produced using 100% combed cotton raw material and tensile strength, elongation, unevenness, yarn defects and hairiness of these yarns were examined. Then, single jersey fabrics were produced from these yarns and their burst strength, abrasion resistance and pilling resistance properties were examined. All test results were also evaluated statistically. As a result, 100% combed cotton ProSPIN yarns were found to have better values in general in all yarn properties than conventional ring yarns, especially in hairiness and breaking tenacity properties. When the test results of single jersey fabrics were evaluated, it was found that knitted fabrics produced using ProSPIN yarns had higher burst strength, abrasion resistance and pilling resistance values.

접힌 권선 링 공진 구조를 이용한 소형 대역통과 필터

This paper proposes a compact bandpass filter using a folded ring resonator, which occupies an area, one-quarter the size of a conventional ring resonator. For the filter design, circuit modeling is used to derive the coupling coefficients between the even- and odd-mode resonances of the proposed resonator with the perturbation stub. The validity of the proposed filter is demonstrated by designing and fabricating a two-pole bandpass filter with a 100 MHz bandwidth at the central frequency of 2.45 GHz.