Locally Constrained Representations in Reinforcement Learning

The success of Reinforcement Learning (RL) heavily relies on the ability to learn robust representations from the observations of the environment. In most cases, the representations learned purely by the reinforcement learning loss can differ vastly across states depending on how the value functions change. However, the representations learned need not be very specific to the task at hand. Relying only on the RL objective may yield representations that vary greatly across successive time steps. In addition, since the RL loss has a changing target, the representations learned would depend on how good the current values/policies are. Thus, disentangling the representations from the main task would allow them to focus more on capturing transition dynamics which can improve generalization. To this end, we propose locally constrained representations, where an auxiliary loss forces the state representations to be predictable by the representations of the neighbouring states. This encourages the representations to be driven not only by the value/policy learning but also self-supervised learning, which constrains the representations from changing too rapidly. We evaluate the proposed method on several known benchmarks and observe strong performance. Especially in continuous control tasks, our experiments show a significant advantage over a strong baseline

Microwave Microlitre Lab-on-Substrate Liquid Characterisation based on SIW Slot Antenna

A microwave microlitre binary liquid mixture concentration detection sensor with potential biological analysis is presented. The microwave lab-on-substrate sensor is fabricated using a substrate integrated waveguide (SIW) slot antenna. The microfluidic channel encapsulating liquid under investigation is located on top of the antenna slot at a quarter wavelength from the short-circuited end of the SIW. The radiated electric nearfield interaction with the liquid mixture exhibits different relationships between the complex permittivity of the liquid mixtures versus the resonant frequency and return loss, discriminating types and percentages of mixed liquid. The sensor was initially demonstrated with three types of samples: deionised water, methanol and air. A resonant frequency shift of 110MHz was measured to discriminate between air and deionised water while we obtained a 20MHz resonant frequency shift between air and methanol. Furthermore, the sensor was used to assess deionised water-methanol mixtures with methanol fractional volumes of 0 to 1 in 0.2 steps. The microwave-microfluidic sensor is contactless, uses readily available materials, cost effective and offers fast and accurate liquid characterisation

A Microfluidic-Integrated SIW Lab-on-Substrate Sensor for Microliter Liquid Characterization

A novel microfluidic-integrated microwave sensor with potential application in microliter-volume biological/biomedical liquid sample characterization and quantification is presented in this paper. The sensor is designed based on the resonance method, providing the best sensing accuracy, and implemented by using a substrate-integrated-waveguide (SIW) structure combining with a rectangular slot antenna operating at 10 GHz. The device can perform accurate characterization of various liquid materials from very low to high loss, demonstrated by measurement of deionized (DI) water and methanol liquid mixtures. The measured relative permittivity, which is the real part of complex permittivity, ranges from 8.58 to 66.12, which is simply limited by the choice of test materials available in our laboratory, not any other technical considerations of the sensor. The fabricated sensor prototype requires a very small liquid volume of less than 7 µl, while still offering an overall accuracy of better than 3 %, as compared to the commercial and other published works. Key advantages of the proposed sensor are that it combines 1.) a very low-profile planar and miniaturized structure sensing microliter liquid volume; 2.) ease of design and fabrication, which makes it cost-effective to manufacture and 3.) noninvasive and contactless measurements. Moreover, since the microfluidic subsystem can potentially be detached from the SIW microwave sensor and, afterward, replaced by a new microfluidic component, the sensor can be reused with no life-cycle limitation and without degrading any figure of merit

Spurious Stopband Improvement of Dual-Mode Dielectric Resonator Filters Using T-shaped Coupling Probe

This paper presents a new design technique for dual-mode dielectric loaded resonator filter operating at 2.18GHz by using T-shape coupling probe. A cylindrical dielectric puck is suspended in the middle of metallic cavity and short-circuited on the side walls. Four vertically etched-slots through the dielectric puck from the top to the base of the ceramic puck offer a high unloaded quality factor of 4300 at the fundamental T E11δ mode and allows the T-shape coupling to be located close to the centre of the dielectric puck. The size reduction ratio in this resonator was 11% compared with air filled coaxial resonator. Fourth-poles Chebyshev bandpass filter (BPF) with planar configuration was designed and implemented by employing two dielectric-loaded cavities. The experimental results show that the spurious-free window of approximately 820 MHz from the fundamental frequency of 2.18GHz and the operational bandwidth of 77 MHz were achieved

エソ筋原繊維タンパク質の脱水および冷凍変性に及ぼす甲殻類エビキチンおよびエビキチン加水分解物の影響

長崎大学学位論文 学位記番号:博(生)甲第55号 学位授与年月日:平成17年3月18

Compact Triple-Mode Microwave Dielectric Resonator Filters

This paper presents a novel and compact triple-mode dielectric resonator (DR) band- pass filter (BPF) based on a single waveguide cavity. A triple-mode resonator can be achieved by pairing the degenerate EH₁₁ modes with a TM01δ mode. The DR structure is composed of two slitted pieces of dielectric pucks that are placed in the middle of a cylindrical metallic cavity. The resonator offers a size reduction ratio of about 15.6% compared with equivalent air-filled coaxial filters. A coaxial probe is used to excite the degenerate EH₁₁ modes while the TM01 mode is excited using a vertical hole etched in the ceramic pucks. Finally, a 3rd order generalised Chebyshev BPF is simulated using HFSS software. The filter has finite transmission zeros(TZ) on the high or low side of the passband

Design study of Low Loss Single-Mode Hollow Core Photonic Crystal Terahertz Waveguide with Support Bridges

We present a design study of an all-polymer low loss single-mode hollow-core photonic crystal (HCPC) terahertz (THz) waveguide with dielectric bridges used as mechanical supports. By exploiting a modal-filtering effect and Brewster phenomenon, we maximize the loss discrimination between the fundamental and other higher order modes resulting in an effectively single-mode operation, though the HCPC THz waveguide is ostensibly multi-mode. Owing to the use of support bridges, which increase the propagation loss, the non-ideal HCPC THz waveguide has higher loss than an ideal one. Nonetheless, the propagation loss of the fundamental HE11 mode can still be minimized, to lower than 5 dB/m over the frequency range from 0.75 to 1.1 THz. In addition, the group velocity dispersion of the HE11 mode is less than -0.5 ps/THz/cm

Novel RF Interference Rejection Technique using a Four-port Diplexer

A novel RF interference rejection technique using four-port network is presented in this paper by using two diplexers combined together. This technique offers the signal isolation of 68.46 dB between transmitter and receiver module, which is the best figure ever reported. The four-port network exploits both high and low-Q factor filters for the cost reduction. The design tolerance with phase deviation between 180º and 183º of four-port network was investigated and the novel concept still has signal isolation (S32) of better than 65.47 dB, which is still superior compared to the existing diplexer. Finally, RF interference rejection technique can be used in wireless communication systems whereas small size, low losses and low complexity are required

Effect of Supplementing Tamarind Seed Husk in Ration on Productive Performance of Fattening Dairy Steer

This  study  aimed  to  investigate  nutrient  composition  and  effects  of  tamarind  seed husk  (TSH)  in  rations  onproductive  performance  of  fattening  dairy  steers.The  TSH  samples from tamarind starch factory were examinednutritional compositions by the proximate analysis and  detergent  method  while  the  bomb  calorimeter  was  used  to  determine  gross  energy.    The results  showed  crude  protein(CP),  fat,  crude  fibers(CF),  nitrogen  free  extract  (NFE),  ash, neutral detergent fiber (NDF), acid detergent fiber (ADF) and gross energy(GE) at 7.23, 0.74, 20.87, 57.44, 1.35, 29.15, 34.74% dry matter and 4,200 Kcal/kg, respectively.  For astudy on effects of TSH in rations on productive performance of fattening dairy steers, 20 at least 87.5% of crossbred Holstein-Friesian steers were divided into 5 groups (block).  Steers in each group were fed  with rations supplemented  with 4 various levels of TSH: 0,2,5, 5.0 and 7.5% at the ratio of 2% of body weight.  Steers were allowed straw and water ad libitum.  The data were analyzed  by  the  randomizedcomplete  block  design.    No  significant  differences  were  found among  treatments  (P>0.05).    The  growth  rates  were  averaged  at  1.16,  1.10,  1.09  and  1.20 kg/steer/day.  The feed conversion rates were 6.93, 7.48, 7.76 and 7.47, and the average feed costs per 1 kg of weight gain were 61.02, 61.54, 64.64, and 59.53 baht, respectively.  It can be concluded that the supplementation of TSH at 0-7.5% in steer rations seems to be practical at the farm