HVAC Optimal Control Based on the Sensitivity Analysis:An Improved SA Combination Method Based on a Neural Network

Aiming at optimizing the energy consumption of HVAC,an energy conservation optimization method was proposed for HVAC systems based on the sensitivity analysis(SA),named the sensitivity analysis combination method(SAC).Based on the SA,neural network and the related settings about energy conservation of HVAC systems,such as cooling water temperature,chilled water temperature and supply air temperature,were optimized.Moreover,based on the data of the existing HVAC system,various optimal control methods ofHVAC systems were tested and evaluated by a simulated HVAC system in TRNSYS.The results show that the proposed SA combination method can reduce significant computational load while maintaining an equivalent energy performance compared with traditional optimal control methods.

两步升温热轧工艺对AZ31镁合金薄板各向异性及成形性能影响

采用两步梯度升温轧制工艺对AZ31镁合金板材进行轧制,探究轧制过程对镁合金板材显微组织织演化、各向异性及成形性能的影响。第I步轧制在300℃开展,其每道次压下量为15%;第II步轧制在550℃进行,其每道次压下量为40%。经过共4道次轧制后,最终获得厚度为1 mm的镁合金薄板。结果显示,第I步低温轧制过程不更换轧制方向时,试样中生成大量剪切带;而更换轧制方向时,组织内部主要为孪晶和再结晶晶粒。随着II步轧制温度的升高,由于动态再结晶急剧激发,剪切带数量及尺寸逐渐减小,晶粒明显细化。根据IGMA分析得出,非基面滑移,特别是棱柱面滑移活动增强。轧制退火后的AZ31镁合金薄板的力学性能得到提高,各向异性减小,冲压成形性能得到明显改善。

Unveiling the planar deformation mechanisms for improved formability in pre-twinned AZ31 Mg alloy sheet at warm temperature

To investigate the role of pre-twins in Mg alloy sheets during warm planar deformation, the stretch forming is conducted at 200 ℃. Results suggest the formability of the pre-twinned AZ31 Mg alloy sheet is enhanced to 11.30 mm. The mechanisms for the improved formability and the deformation behaviors during the planar stretch forming are systematically investigated based on the planar stress states. The Schmid factor for deformation mechanisms are calculated, the results reveal that planar stress states extremely affect the Schmid factor for {10-12}twinning. The detwinning is activated and the prismatic slip is enhanced in the pre-twinned sheet, especially under the planar extension stress state in the outer region. Consequently, the thickness-direction strain is accommodated better. The dynamic recrystallization(DRX) type is continuous DRX(CDRX) regardless of the planar stress state. However, the CDRX degree is greater under the planar extension stress state.Some twin lattices deviate from the perfect {10-12} twinning relation due to the planar compression stress state and the CDRX. The basal texture is weakened when the planar stress state tends to change the texture components.

Phytoestrogen-derived multifunctional ligands for targeted therapy of breast cancer

Nano-targeted delivery systems have been widely used for breast tumor drug delivery.Estrogen receptors are considered to be significant drug delivery target receptors due to their overexpression in a variety of tumor cells.However,targeted ligands have a significant impact on the safety and effectiveness of active delivery systems,limiting the clinical transformation of nanoparticles.Phytoestrogens have shown good biosafety characteristics and some affinity with the estrogen receptor.In the present study,molecular docking was used to select tanshinone IIA(Tan IIA)among phytoestrogens as a target ligand to be used in nanodelivery systems with somemodifications.Modified Tan IIA(Tan-NH2)showed a good biosafety profile and demonstrated tumor-targeting,anti-tumor and anti-tumor metastasis effects.Moreover,the ligand was utilized with the anti-tumor drug Dox-loaded mesoporous silica nanoparticles via chemical modification to generate a nanocomposite Tan-Dox-MSN.Tan-Dox-MSN had a uniform particle size,good dispersibility and high drug loading capacity.Validation experiments in vivo and in vitro showed that it also had a better targeting ability,anti-tumor effect and lower toxicity in normal organs.These results supported the idea that phytoestrogens with high affinity for the estrogen receptor could improve the therapeutic efficacy of nano-targeted delivery systems in breast tumors.

MAQMC:Multi-Agent Deep Q-Network for Multi-Zone Residential HVAC Control

The optimization of multi-zone residential heating,ventilation,and air conditioning(HVAC)control is not an easy task due to its complex dynamic thermal model and the uncertainty of occupant-driven cooling loads.Deep reinforcement learning(DRL)methods have recently been proposed to address the HVAC control problem.However,the application of single-agent DRL formulti-zone residential HVAC controlmay lead to non-convergence or slow convergence.In this paper,we propose MAQMC(Multi-Agent deep Q-network for multi-zone residential HVAC Control)to address this challenge with the goal of minimizing energy consumption while maintaining occupants’thermal comfort.MAQMC is divided into MAQMC2(MAQMC with two agents:one agent controls the temperature of each zone,and the other agent controls the humidity of each zone)and MAQMC3(MAQMC with three agents:three agents control the temperature and humidity of three zones,respectively).The experimental results showthatMAQMC3 can reduce energy consumption by 6.27%andMAQMC2 by 3.73%compared with the fixed point;compared with the rule-based,MAQMC3 andMAQMC2 respectively can reduce 61.89%and 59.07%comfort violation.In addition,experiments with different regional weather data demonstrate that the well-trained MAQMC RL agents have the robustness and adaptability to unknown environments.

用于眼后段持续给药的原位pH触发凝胶系统中三七总皂苷的研制与评价

目的:为三七总皂苷(PNS)在pH敏感型原位凝胶中的研究及相关制剂的开发和改进奠定基础。方法:我们使用Carbopol■940(一种常用的pH敏感聚合物)和增稠剂羟丙基甲基纤维素(HPMC E4M)作为眼用凝胶基质来制备PNS眼用原位凝胶。此外,通过评估凝胶能力和体外释放研究结果进行配方优化。还进行了体外(角膜渗透、流变学和稳定性)和体内(眼部刺激和玻璃体的初步药代动力学)研究。结果:研究表明,含有三七总皂苷的原位凝胶系统显示出药物的缓释性,使其成为改善眼后生物利用度的理想眼部给药系统。结论:本研究为原位pH触发凝胶中PNS的研究及相关制剂的开发和改进奠定了基础。同时,它将传统中药与现代原位凝胶技术相结合,为糖尿病视网膜病变等后眼病的治疗提供了新的方向。

Acetate coverage effect on the reactivity of vinyl acetate synthesis on Pd/Au alloy surfaces

Vinyl acetate (VA) synthesis on Pd/Au(111) and Pd/Au(100) surfaces has been systematically investigated through first-principles density functional theory (DFT) calculations. The DFT results showed that for VA synthesis, the 'Samanos' reaction mechanism (i.e., direct coupling of coadsorbed ethylene and acetate species and subsequent β-hydride elimination to form VA) is more favorable than the 'Moiseev' mechanism (i.e., ethylene first dehydrogenates to form vinyl species which then couple with the coadsorbed acetate species to form VA). More importantly, it was found the surface coverage of acetate has a significant effect on the reactivity of VA synthesis, and the activation energy of the rate-controlling step on Pd/Au(100) surface is smaller than that on Pd/Au(111) surface (0.88 vs. 0.95 eV), indicating the former is more active than the latter.

The anti-pulmonary fibrosis of Salvia miltiorrhiza Bunge: A systematic review

The characteristics of PF are diffuse alveolitis and disruption of alveolar structure leading to pulmonary interstitial fibrosis.At the same time,pulmonary fibrosis reduces lung volume and restricts ventilation,ultimately leading to hypoxemia and respiratory failure.In clinical guidelines,Nintedanib or Pirfenidone is often used for treatment.However,the two drugs,although they may slow the progression of the disease,cannot stop,or reverse fibrosis and generally result in a variety of toxic side effects.In 184-220 A.D.,it was already recorded in Supplementary Records of Famous Physicians that the function of SMB was to invigorate blood circulation and disperse blood stasis.In modern medical research,the active ingredients of SMB have likewise been found to be used in treatments such as anti-fibrosis,anti-inflammatory,antithrombotic,antioxidant,microcirculatory improvement,and antineoplastic.In this review,a comprehensive search of the former literature on SMB and pulmonary fibers was conducted using databases including PubMed,CNKI,the National Science and Technology Library,Hindawi,Chinese Science and Technology Journal Database,and the Scientific Network Database.Meanwhile,this review presents the mechanisms of the active ingredients in SMB which have anti-pulmonary fibrosis effects through the signal pathways,cytokines,inflammation response,oxidative stress,apoptosis,and matrix metalloproteinases.SMB could offer a direction for therapy for pulmonary fibrosis by identifying the possible active components and exploring the potential mechanisms.Those could provide a reference for further research and application of SMB in the treatment of pulmonary fibrosis.

Efect of Pre‑stretch Strain at High Temperatures on the Formability of AZ31 Magnesium Alloy Sheets

High-temperature pre-stretching experiments were carried out on the AZ31 Mg alloy at 723 K with strain levels of 2.54%,6.48%,10.92%,and 19.2%to alter the microstructure and texture for improving room-temperature formability.The results showed that the strain-hardening coefcient increased,while the Lankford value decreased.In addition,the Erichsen values of all pre-stretch sheets were enhanced compared with that of the as-received sheet.The maximum Erichsen value increased from 2.38 mm for the as-received sample to 4.03 mm for the 10.92%-stretched sample,corresponding to an improvement of 69.32%.This improvement was mainly attributed to the gradual increase in grain size,and the(0001)basal texture was weakened due to the activated non-basal slip as the high-temperature pre-stretching strain levels increased.The visco-plastic self-consistent analysis was performed on the as-received and high-temperature pre-stretched samples.Results confrmed the higher activity of the prismatic slip in 10.92%-stretched sample,leading to divergence and weakening of basal texture components.This results in an augmentation of the Schmid factor under diferent slip systems.Therefore,it can be concluded that high-temperature pre-stretching technology provided an efective method to enhance the formability of Mg alloy sheets.

MAML^(2):meta reinforcement learning via meta-learning for task categories

Meta-learning has been widely applied to solving few-shot reinforcement learning problems,where we hope to obtain an agent that can learn quickly in a new task.However,these algorithms often ignore some isolated tasks in pursuit of the average performance,which may result in negative adaptation in these isolated tasks,and they usually need sufficient learning in a stationary task distribution.In this paper,our algorithm presents a hierarchical framework of double meta-learning,and the whole framework includes classification,meta-learning,and re-adaptation.Firstly,in the classification process,we classify tasks into several task subsets,considered as some categories of tasks,by learned parameters of each task,which can separate out some isolated tasks thereafter.Secondly,in the meta-learning process,we learn category parameters in all subsets via meta-learning.Simultaneously,based on the gradient of each category parameter in each subset,we use meta-learning again to learn a new metaparameter related to the whole task set,which can be used as an initial parameter for the new task.Finally,in the re-adaption process,we adapt the parameter of the new task with two steps,by the meta-parameter and the appropriate category parameter successively.Experimentally,we demonstrate our algorithm prevents the agent from negative adaptation without losing the average performance for the whole task set.Additionally,our algorithm presents a more rapid adaptation process within readaptation.Moreover,we show the good performance of our algorithm with fewer samples as the agent is exposed to an online meta-learning setting.

Respiratory arrest associated with polymyxin B in a lung transplant patient

To the Editor:The polymyxin antibiotics colistin(polymyxin E)and polymyxin B(PMB)became available in the 1950s;thus,they did not undergo contemporary drug development procedures.Their clinical use has recently resurged,assuming an important role as salvage therapv for otherwise untreatable gram-negative infection.[1]Multidrug-resistant(MDR)bacterial infections are primarily caused by gram-negative bacilli(GNB),such as Pseudomonas aeruginosa and Klebsiella pneumoniae^in lung transplant(LT)patients.[2]The increasing prevalence of MDR-GNB infections in LT patients has led to an upsurge in the use of these“older”drugs.During the treatment course,we should pay attention to severe and life-threatening respiratory paralysis caused by neuromuscular blockage associated with PMB.Herein,we report a rare case of a 67-year-old LT patient who suffered from respiratory arrest induced by PMB.