KM1型空间辐射制冷器环境模拟设备研制

研制了一台空间辐射制冷器热模拟试验专用的清洁无油环境模拟设备。着重论述了其主要结构、性能指标及设计思路和原理 ,给出了辐射制冷器热模拟试验结果和在轨测试结果。

用蒙特卡罗法计算G型空间辐射制冷器的耦合因子

采用蒙特卡罗法计算了G型空间辐射制冷器的耦合因子.在计算中通过积分分布概率方程确定了发射能束,跟踪了复杂曲面系统的反射过程,提出了计算结果的误差估算方法,并采用计算机系统时间作为计算伪随机数据的工作条件,这在一定程度上避免了伪随机数的周期性出现.计算结果表明,蒙特卡罗法能够有效地计算G型空间辐射制冷器的耦合因子,计算误差同几何面的大小成反比,并且通过增加随机能束数,减小了不确定性对结果的影响,提高了计算结果的精度.

为真实的世界而设计——大变局时代的设计思维定势分析

当设计思维定势与其所服务的现实世界紧密关联时,是经验的总结与智慧的结晶;当设计思维定势与现实世界脱离关系时,就会成为设计创新的阻碍。在大变局的时代背景下,一些设计师难以顺应时代变化,不能从设计思维定势中脱离出来。针对这种现象,文章以文献法和案例法进行分析,指出设计思维定势形成阻碍的内在原因是设计师忽视了大变局时代设计服务的本质属性变化、设计技术整合的趋势以及设计需求的变化,根本原因是设计师沉浸在自我世界里,忽视了为真实世界而设计的本义。

探究中国现代化的微观逻辑——以1959年中国革命博物馆和中国历史博物馆为例

不同于当前来自哲学社会科学领域以宏观尺度为主的中国式现代化理论体系与话语体系研究,本文考察中国现代化进程中城市建筑领域所呈现的微观历史逻辑。1959年建成的中国革命博物馆和中国历史博物馆,作为新中国现代化早期“十大建筑”之一,成为本文理想研究个案。今天来看,中国革命博物馆和中国历史博物馆的空间生产过程,在国家现代化、社会现代化、城市现代化三个方面,均显现出决策者、设计者与建造者的重要贡献:一是在国家现代化方面,准确研判了符合中国特色社会主义国家身份的文化模板;二是在社会现代化方面,协同发明了经济与速度条件下“边设计边施工”的社会生产逻辑;三是在城市现代化方面,创造性并置了北京城市双重“左祖右社”的空间逻辑。中国革命博物馆和中国历史博物馆个案体现出中国现代化进程有丰富、辩证与复杂的微观历史逻辑,对深入理解中国式现代化理论体系的内涵具有启示意义。

oncausal spatial prediction filtering based on an ARMA model

Conventional f-x prediction filtering methods are based on an autoregressive model. The error section is first computed as a source noise but is removed as additive noise to obtain the signal, which results in an assumption inconsistency before and after filtering. In this paper, an autoregressive, moving-average model is employed to avoid the model inconsistency. Based on the ARMA model, a noncasual prediction filter is computed and a self-deconvolved projection filter is used for estimating additive noise in order to suppress random noise. The 1-D ARMA model is also extended to the 2-D spatial domain, which is the basis for noncasual spatial prediction filtering for random noise attenuation on 3-D seismic data. Synthetic and field data processing indicate this method can suppress random noise more effectively and preserve the signal simultaneously and does much better than other conventional prediction filtering methods.

A Study on Feelings of Worriment Due to Middle-Sized Robot in Living Space

Recently, the demand of services for architectural space is more increasing due to the diversification and complication of people＇s needs. In this research, it is assumed that the robot will support people＇s various needs and people＇s lives in the near future. In this study, the authors investigated the relationship between a robot and a person in quasi space close to actual life space. The authors carried out an experiment to clarify the feelings of worriment due to a robot in the living room in the case of Japanese males. This research aims to establish architecture techniques for robots and humans living together. In this experiment, the robot approached a male sitting on a sofa in quasi space. At different distances between the robot and the male, the subject evaluated his feelings of worriment from ＂no worriment＂ to ＂worriment＂ in five steps from one to five. The robot used in this experiment is middle-sized （380 mm （L） × 380 mm （W） × 350 mm （H））. In this experiment, it is considered that the robot asks for help outside when an emergency occurs. In this experiment, the authors had three situations for the subject： watching television, reading a magazine and just sitting.

Responsive Prototypes： Urban Machines as a Framework for the Digital City

Over the last few decades, a diverse and expanded practice has emerged from the increasingly collaborative work developed among architects, urbanists, artists, and media designers. This collaboration has more and more developed a particular landscape of projects which share the same operative principles and modes of operation. The city at large has been the context where these projects have been implemented and developed with the will of bringing these types of experimentation to the people and to the public and social scale. Cities are continuously produced through entropic processes that mediate between complexity and immediacy. Information technology operates as a linkage able to set up new rules for communication between man and matter. In this framework, by looking at spatial interventions in the urban space, the aim of the paper is to dissect the modes in which spatial practitioners operate in the digital city through ＂Urban Machines＂ and how information technology becomes a tool for place-making. The paper looks at integrated systems or machines that have spatial, social, and environmental implication in how we experience the city. Machines imply ＂something that has been constructed＂ and ＂function with a specific purpose＂ while being composed by parts that respond to a ＂functioning whole＂. These interventions start from sharing the same principle： How do we generate through technologically mediated experiences opportunities for new types of production of（social）space？; How such systems shape our urban experience and deploy forms of participation in civic life？.

On Impulse Switching Functions of Inverters as an Orthogonal System

The paper deals with impulse switching function which are used as exciting functions of one- and multidimensional state-space models of power electronic converters. Obviously, these functions are harmonic but using power converters they can be strongly non-harmonic, sometimes piecewise constants with zero spaces between them. Then, one deals with power series of time pulses. The impulse switching functions which are orthogonal ones can be derived from these series. The new impulse switching functions are created using Z-transform, inverse Z-transform and numerical series/sequences. The impulse switching functions created this way can be used for both steady- and transient state investigation of converters.

Simulation of higher-order topological phases and related topological phase transitions in a superconducting qubit

Higher-order topological phases give rise to new bulk and boundary physics,as well as new classes of topological phase transitions.While the realization of higher-order topological phases has been confirmed in many platforms by detecting the existence of gapless boundary modes,a direct determination of the higher-order topology and related topological phase transitions through the bulk in experiments has still been lacking.To bridge the gap,in this work we carry out the simulation of a twodimensional second-order topological phase in a superconducting qubit.Owing to the great flexibility and controllability of the quantum simulator,we observe the realization of higher-order topology directly through the measurement of the pseudo-spin texture in momentum space of the bulk for the first time,in sharp contrast to previous experiments based on the detection of gapless boundary modes in real space.Also through the measurement of the evolution of pseudo-spin texture with parameters,we further observe novel topological phase transitions from the second-order topological phase to the trivial phase,as well as to the first-order topological phase with nonzero Chern number.Our work sheds new light on the study of higher-order topological phases and topological phase transitions.

Dynamics of tether-tugging reorbiting with net capture

To control the growth of space debris in the geostationary earth orbit （GEO）, a novel solution of net capture and tether-tugging reorbiting is proposed. After capture, the tug （i.e., active spacecraft）, tether, net, and target （i.e., GEO debris） constitute a rig- id-flexible coupled tethered combination system （TCS）, and subsequently the system is transported to the graveyard orbit by a thruster equipped on the tug. This paper attempts to study the dynamics of tether-tugging leorbiting after net capture. The net is equivalent to four flexible bridles, and the tug and target are viewed as rigid bodies. A sophisticated mathematical model is developed, taking into account the system orbital motion, relative motion of two spacecraft and spacecraft attitude motion. Given the complexity of the model, the numerical method is adopted to study the system dynamics characteristics. Particular attention is given to the investigation of the possible risks such as tether slack, spacecraft collision, tether rupture, tether-tug intertwist and destabilizing of the rug＇s attitude. The influence of the initial conditions and the magnitudes of the thrust are studied.

Monte Carlo Likelihood Estimation of Mixed-Effects State Space Models with Application to HIV Dynamics

The statistical inference for generalized mixed-effects state space models （MESSM） are investigated when the random effects are unknown. Two filtering algorithms are designed both of which are based on mixture Kalman filter. These algorithms are particularly useful when the longitudinal ts are sparse. The authors also propose a globally convergent algorithm for parameter estimation of MESSM which can be used to locate the initial value of parameters for local while more efficient algorithms. Simulation examples are carried out which validate the efficacy of the proposed approaches. A data set from the clinical trial is investigated and a smaller mean square error is achieved compared to the existing results in literatures.

Closed Timelike Curves in Type Ⅱ Non-Vacuum Spacetime

Here we present a cyclicly symmetric non-vacuum spacetime, admitting closed timelike curves(CTCs) which appear after a certain instant of time,i.e.,a time-machine spacetime. The spacetime is asymptotically flat, freefrom curvature singularities and a four-dimensional extension of the Misner space in curved spacetime. The spacetime is of type Ⅱ in the Petrov classification scheme and the matter field pure radiation satisfy the energy condition.