Oven Control Research Articles

An oven controlled piezoelectric MEMS dual-resonator platform with frequency stability of [formula omitted]100 ppb over industrial temperature range

This work demonstrates a piezoelectric MEMS dual-resonator platform with an oven control. The platform includes a micro-oven in-chip, which integrates a frequency output resonator and a temperature sensing resonator. The two resonators operate using a phase-locked loop system, one in width-extensional (WE) mode and the other in width-shear (WS) mode. An equivalent thermal model of the dual-resonator platform is established and both resonators exhibit extremely uniform temperature distributions. The real-time temperature of the resonators is monitored by measuring the frequency difference between the two resonators and a closed-loop oven control is implemented to maintain the dual-resonator platform at an oven-set temperature. The reported oven controlled piezoelectric MEMS dual-resonator platform exhibits a measured frequency stability of ±100 ppb across the industrial temperature range of −40 to 85 °C. This result signifies the promising potential of the device in high-end timing applications.

Optimizing winged-bean meal through oven and autoclave heating as viable alternative for plant-based aquafeed

Winged-bean meal can serve as a substitute for soybean meal in plant-based fish feed, despite its trypsin-inhibitor properties, which can be alleviated through heating processes. This study aimed to explore the potential of winged-bean meal subjected to different heating methods, namely oven (110 °C for 30 minutes) and autoclave (121 °C for 30 minutes), based on proximate analysis and trypsin activity. The study applied three treatments with four replications: oven heating (O), autoclave heating (A), and control (without heating, E). All data were analyzed using analysis of variance and Duncan’s multiple range test to determine the best treatment. Data were also compared to the nutrient requirements of several cultured freshwater fish in Indonesia. Heating treatments improved in vitro trypsin activity (1300 units/O and 1135 units/A vs. 835 units) but reduced protein (29.05±1.96%/A and 31.73±1.52%/O vs. 35.17±0.38%) and moisture contents. Additionally, the O treatment met the standards for aquafeed protein content (27-45%) and potentially fulfilled the protein requirements for catfish (25-40%), Nile tilapia (30-35%), and Java barb (30-32%). Therefore, oven heating presents a viable candidate as an alternative plant-based aquafeed ingredient. Nevertheless, the in vivo application of winged-bean meal as an aquafeed ingredient should be further evaluated to determine whether heating treatment effectively enhances digestive activity, nutrient retention, and growth performance in target fish species.

High Precision Hemispherical Resonator Gyroscopes With Oven Control Systems

This work presents a high reliable hemispherical resonator gyroscope (HRG) with a solution of an oven control system. The dynamics and thermal characteristics are firstly analyzed with a indication that the conventional look-up table (LUT) method can not fully compensate the HRG errors. The temperature cycling experiments show the hysteresis effect of the key parameters of HRG and fit the theoretical analysis. Then an advanced oven control approach is proposed to solve the challenges with optimized mechanical isolation, sensing and actuation electronics. The experimental verification results illustrate a comprehensive improvement for the HRG. Particularly, the bias instability (BI) is one order of magnitude better than uncompensated HRG that reaches a sub 0.001°/hr level. The daily bias and scale factor repeatability is 6× and 3× improved with a 1 week measurement, respectively. It also shows an excellent robustness to the environmental variation by doing a temperature cycling test. The bias level error of the uncompensated system is improved by 40×, and the scale factor stability can be also increased up to 19×. The BI and rate random walk (RRW) are all significantly enhanced to show a good environmental adaptability of the proposed ovenized HRG.

Global H3K79 di-methylation mediates DNA damage response to PAH exposure in Chinese coke oven workers.

Polycyclic aromatic hydrocarbons (PAHs) are the main contaminants of coke oven emissions which can induce serious genetic damage in coke oven workers. Epigenetic alternations play essential roles in the regulation of DNA damage effect of PAHs. Previous studies indicate that H3K79 di-methylation (H3K79me2) is integral in DNA damage repair. However, the potential role of H3K79me2 in DNA damage response (DDR) following PAHs exposure is still unclear. In this study, we recruited 256 male coke oven workers and control workers, and examined H3K79me2 and DNA damage in their peripheral blood lymphocytes (PBLCs). The results showed that global H3K79me2 of coke oven workers was 29.3% less than that of the controls (P<0.001). The H3K79me2 was negatively correlated with the concentration of urinary 1-hydroxypyrene (1-OHP) (β=-0.235, P<0.001) and level of genetic damage evaluated by comet assay (βTail DNA %=-0.313, P<0.001; βOTM=-0.251, P=0.008). Consistently, we found that benzo(a)pyrene (BaP) inhibited H3K79me2 in immortalized human bronchial epithelial (HBE) cells in a time-dependent manner. In order to explore the function of H3K79me2 in PAHs DDR, we established histone 3.1/3.3 K79A mutant cells (H3K79A) to suppress H3K79me2. H3K79A cells showed more serious DNA damage and decreased cell viability than control cells after BaP treatment. In addition, we also found that the expression of DOT1L, the only methyltransferase in H3K79, was repressed by BaP dose-dependently. DOT1L knockdown resulted in decreased H3K79me2 level and aggravated DNA damage after BaP exposure. This suggests that BaP induces H3K79me2 repression via inhibiting DOT1L expression. In conclusion, these findings indicate that PAH exposure decreases the level of global H3K79me2, which is integral for DNA damage response regulation of PAHs.

A Digitally Programmable CMOS Feedback ASIC for Highly Stable MEMS-Referenced Oscillators

This paper describes a digitally programmable single-chip feedback ASIC for MEMS-referenced oscillators in the 0.4–15-MHz range. The chip contains a differential-difference low-noise amplifier (DD-LNA), a variable-gain amplifier (VGA) for analog gain control, several programmable-gain amplifiers (PGAs) for digital gain control, two second-order active $R-C$ band-pass filters (BPFs) for band selection, two all-pass filters (APFs) for phase shifting, an automatic level control (ALC) loop, and differential output buffers to allow interfacing with a wide variety of MEMS devices. Many on-chip parameters are digitally programmable via a standard serial peripheral interface (SPI) bus, thus allowing fine-grained optimization of the overall feedback transfer function. In addition, a compensation path with its own PGAs, a programmable attenuator, and an APF is provided for canceling electrical feedthrough within the chosen MEMS resonator. The chip was designed in 180-nm CMOS and consumes 4.6 mW. It was used to realize a ~6.9-MHz low-phase-noise (−105 dBc/Hz at 10 Hz) oscillator based on an ultra-high- $Q$ ( $\sim 3.2\times 10^{6}$ at a bias voltage of 35 V) wafer-level vacuum-encapsulated Lame mode single-crystal Silicon (SCS) MEMS resonator. Oven control and active temperature compensation improve the oscillator’s frequency stability to ±0.5 ppm with an Allan deviation of $1 \times 10^{-8}$ at $10^{3}$ s. Two such oscillators were also electrically coupled to realize a low-phase-noise quadrature reference oscillator suitable for complex-domain PLLs.

Oven controlled N++ [1 0 0] length-extensional mode silicon resonator with frequency stability of 1 ppm over industrial temperature range

This paper presents an oven controlled N++ [1 0 0] length-extensional mode silicon resonator, with a lookup-table based control algorithm. The temperature coefficient of resonant frequency (TCF) of the N++ doped resonator is nonlinear, and there is a turnover temperature point at which the TCF is equal to zero. The resonator is maintained at the turnover point by Joule heating; this temperature is a little higher than the upper limit of the industrial temperature range. It is demonstrated that the control algorithm based on the thermoresistor on the substrate and the lookup table for heating voltage versus chip temperature is sufficiently accurate to achieve a frequency stability of ±0.5 ppm over the industrial temperature range. Because only two leads are required for electrical heating and piezoresistive sensing, the power required for heating of this resonator can be potentially lower than that of the oscillators with closed-loop oven control algorithm. It is also shown that the phase noise can be suppressed at the turnover temperature because of the very low value of the TCF, which justifies the usage of the heating voltage as the excitation voltage of the Wheatstone half-bridge.

The comparison of reproductive hormones and liver enzymes in coke oven workers and control group

The comparison of reproductive hormones and liver enzymes in coke oven workers and control group

Coke Oven Intelligent Integrated Control System

In order to improve the level of management and control of coke oven, the research on intelligent integrated control system is carried out. In modern advanced control system of coke oven, the control scheme of feedback combined with feed-forward, and control merged with management are widely utilized. The integrated management and control system of coke oven is introduced systematically, including the system model, production plan and management, heating control system, the model and method of evaluating temperature, intelligent combustion control and the pressure control gas collector of coke oven. It is pointed out that the integration of management and control develops towards the orientation of coke oven control system. Considering the complexity and importance of flue temperature control in coke oven heating process, the control method of combining the stopping heating time control with the heating gas flow adjustment is proposed, hybrid intelligent control models of flue temperature are built.

Intelligent Control and Management Integrated System of Coke Oven

In order to improve the level of control and management of coke oven, the research on control and management integrated system is carried out. In modern advanced control system of coke oven, the control scheme of feedback combined with feed-forward, and control merged with management is widely used. The integrated control and management system of coke oven is introduced systematically, including the system model, production planning and management, heating control system, the model and method of evaluating temperature, intelligent combustion control and the pressure control gas collector of coke oven. It is pointed out that the integration of control and management is the developing orientation of coke oven control system.

Aromatic DNA adduct levels in coke oven workers: correlation with polymorphisms in genes GSTP1, GSTM1, GSTT1 and CYP1A1

The aim of this study was to use DNA adducts levels, detected by 32 P -postlabelling, as a biomarker to assess human exposure to polycyclic aromatic hydrocarbons (PAHs) from a coke oven plant and explore the possible association between CYP1A1 MspI, GSTP1, GSTM1 and GSTT1 genotypes, and smoking status on bulky DNA adduct formation. A large amount of inter-individual variation in adduct level was observed among workers with the same job and the same smoking habits. No significant differences were observed in DNA adduct levels between the coke oven workers and control group. Smokers in the control group had significantly higher DNA adducts than the non-smokers in the same group (35.13±21.11 versus 11.18±8.00, per 10 8 nucleotides, P=0.003). In this group, the correlation between the level of DNA adducts and the cigarettes smoked was strongly significant ( r=0.70, P<0.0005), but no correlation was found among the coke oven workers. Among non-smokers there was a significant difference between the control group and the coke oven workers (11.18±8.00 versus 24.62±15.20, per 10 8 nucleotides, P=0.03). These results suggests that tobacco smoke could behave as a confounding factor for evaluation of DNA adducts arising from occupational exposure. The levels of DNA adducts in smokers not occupationally exposed to PAHs is dependent on the polymorphisms CYP1A1 MspI in the 3′ non-coding region (49.04±22.18 versus 25.85±15.87, per 10 8 nucleotides, P<0.05), but no effect was observed for the GST genotypes studied.

The Cook, the Cooker and the Gendering of the Kitchen

This article combines the approaches of actor-network theory and poststructuralism to consider how a household technology has interacted with patterns of gender hierarchies over time. Two major innovations in cooking technologies are analysed in relation to cooking activities and the related conceptions of women's roles in families, which are central to these concerns. The first technological development is the thermostat oven control, introduced in the 1920s and 1930s; the second is the microwave oven, introduced in the late 1980s and 1990s. Important conceptions of the cook's performance are examined and various implicit roles that have been tacitly assumed by innovating agents in the use of cookers are made explicit. The study contributes to discussions of gender and technology in the context of domestic life.

Convection automated logic oven control

We describe a patented automated cooking process called Convection AutoLogic (CAL). The beauty of our technology is that it requires no extra hardware for the existing oven system. We use the existing temperature probe, whether it is an RTD, thermocouple, or thermistor. This means that the manufacturer does not have to be burdened with extra costs associated with automated cooking in comparison to standard ovens. The only change to the oven is the program in the central processing unit (CPU) on the board. As for its operation, when the user places the food into the oven, he or she is required to select a category (e.g., beef, poultry, or casseroles) and then simply press the start button. The CAL program then begins its cooking program. It first looks at the ambient oven temperature to see if it is a cold, warm, or hot start. CAL stores this data and then begins to look at the food's thermal footprint. After CAL has properly detected this thermal footprint, it can calculate the time and temperature at which the food needs to be cooked. CAL then sets up these factors for the cooking stage of the program and, when the food has finished cooking, the oven is turned off automatically. The total time for this entire process is the same as the standard cooking time the user would normally set. The CAL program can also compensate for varying line voltages and detect when the oven door is opened. With all of these varying factors being monitored, CAL can produce a perfectly cooked item with minimal user input.

Stable high-temperature (500 °C) thermistors

Thermistors which are stable in their resistance-temperature characteristic after extended high-temperature exposure have been formed by attaching platinum wires or Fernico (Kovar) ribbons with Birox thick film paste to thermistor spinel material (from two vendors) with a resistivity of 2000 Ω cm. Other resistivity compositions were not stable at elevated temperatures. Shifts in the original calibration curve were less than 2 °C at room temperature after 10 000 h at 240 °C, even with periodic jumps to 500 °C. Held and measured at 500 °C, resistance shifts were less than 2 °C for periods up to 750 h. These thermistor structures should provide low-cost, stable, reliable, and interchangeable temperature sensors for oven and furnace measurement and control.

The design of domestic electric cookers

The paper is devoted chiefly to those aspects of cooker design by which cooking performance is affected. Mechanical design is reviewed, but in much less detail, and mainly with the object of recording present practice.The question of the indication of the “heating condition” of ovens is discussed, and the desirability is stressed of taking account of radiation as well as air temperature. Consideration is given to the problem of oven ventilation, particularly from the point of view of its effect on “steaming” at the vent. The Advantages offered by thermostatic oven control are outlined and an attempt is made to forecast the changes, especially in connection with methods of heating and lagging, to which it is likely to lead.The history of the development of boiling-plates is briefly reviewed, and the relative advantages and disadvantages of the various methods of construction commonly employed in this country are discussed.