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In this paper the logical structure of contactless telemechanical system for distributed objects is discussed. A simple method of variable system structure for transmitting and receiving telemechanical information is adopted. The idea is that the information oc-curred in every controlled point (station) and the information of some of those objects,which frequently change their states, are transmitted continually and cyclically, while for other objects their information is transmitted only after any change in... In this paper the logical structure of contactless telemechanical system for distributed objects is discussed. A simple method of variable system structure for transmitting and receiving telemechanical information is adopted. The idea is that the information oc-curred in every controlled point (station) and the information of some of those objects,which frequently change their states, are transmitted continually and cyclically, while for other objects their information is transmitted only after any change in their states. Thus,the speed of operation will be increased, and also the error probability of system syn-chronization will be decreased. For the realization of the variable logical system struc-ture, several blocks are used repetitively. For example, two commutators and one sim-ple logical unit are used to construct a simple automatic sequential encoder, and at the same time, the two commutators are used also to operate as a matrix commutator for receiving telesignalling information etc. Therefore the system is comparatively simplified and attains a higher degree of "minimization". 本文研究了无触点集中-分散目标远动系统的逻辑结构.文中提出了采用简单的系统变结构来发送和接收信息的逻辑结构方式.对被控制点及一部分比较重要或变化比较频繁的被控制目标的信息,保留了循环传送,而对大部分变化比较慢的被控制目标则采用目标有变化时才传送信号的方式,这样就提高了系统的平均动作速度,同时也减小系统的失步概率.文中采用环节的复合利用及简化的逻辑单元线路来实现这种系统的逻辑结构.例如用两个分配器和一个简单的逻辑单元“和”线路组成了很简化的选点自动程序编码器,同时这两个分配器又复合利用兼组成目标信号接收矩阵式分配器等,因而可以使得这种系统同时又具有较高的极简化度. In order to determine flood discharges in rivers without any previous hydrometric record, estimation according to its trace is the only approximation method that is comparatively reliable. The method requires only to find the flood trace, measure its slope and section of flow, estimate the channel roughness, and then substitute these data into hydraulic formulas to calculate the velocity and discharge. Although the results thus obtained may not be accurate, and it is impossible to ascertain the probability of... In order to determine flood discharges in rivers without any previous hydrometric record, estimation according to its trace is the only approximation method that is comparatively reliable. The method requires only to find the flood trace, measure its slope and section of flow, estimate the channel roughness, and then substitute these data into hydraulic formulas to calculate the velocity and discharge. Although the results thus obtained may not be accurate, and it is impossible to ascertain the probability of occurrence corresponding to the flood, nevertheless, the data based upon are direct, and so the errors are low in comparison with those of indirect methods, such as the hydro-meteorological and the analogical, which might even yield radically unreliable results. Besides, in the statistical method of estimating flood flows, this method has been used to supplement those extraordinary flood data not recorded in history and yet valuable for statistics.The current method of estimating flood discharges from its trace assumes the state of steady flow and its velocity formula, from which it is impossible to obtain the maximum discharge that actually happens in the state of unsteady flow, and is only possible to calculate the discharge at maximum water level smaller than the peak discharge. This paper analyzes the shortcomings of the current method and suggests another means of estimating by taking average of the upper and lower limits of the maximum discharge. The error of estimation in the new method will not be over 17% by analysis, which, as compared with the standard of allowable error in hydrometrical survey, is not considerable. 工程設計中,欲在未經水文測驗的河流上定出設計用的洪水流率,依据洪水痕跡估算是唯一此較可靠而近似的方法。这方法只須調查洪水痕跡,測量其坡度及过水断面,估計河槽糙度,就可代入水力学中的公式而算出流速和流率,虽然这样所得的結果未必准确,且無从得知这次洪水相应的概率,但所憑借的资料是直接的,因而誤差的程度此較还小;不象水文气象法从雨量間接推算,或各种此照法依据其他流域的資料間接估計,可能得出很不可靠的結果。在流率資料統計法中,这方法也曆来增补那些历史上未曾测得的特大的可貴的洪水流率資料。 現行从洪水痕跡估算流率的方法假設了水力学中穩定流的流速公式,不能得出实际發生的不定流中的最大流率,而只約略算出那較小的最高水位吋的流率,憑以設計工程是不安全的。本文分析了現行方法的缺点所在,建議另一估算的方法,从最大流率的上下兩極限值取其平均数以估計之。新的方法的沽算誤差,循理推論,不会超过17%;衡以流速仪測量流率的許可誤差标准,並不算大。 Minute amount of sulfur dioxide and impurities are always present in the air of industrial area. Under sunlight, smog is formed, scattering light and reducing visibility. This article is to ascertain the effect of rate of photochemical oxidation of sulfur dioxide in air at high relative humidities. 工业区大气中常含微量二氧化硫及各种杂质。天晴时可能形成烟雾,分散光线,减缩视距,本研究即系确定其影响。 实验时以经过特种过滤器所得纯粹空气与二氧化硫在不同湿度下混合,贮於Lucite容器(7.94升),用RS日光灯自顶部相继透过红外线过滤器及Plexiglas IA照耀达1至2小时。光切断后作用即中断。所得硫酸气溶胶质点大小作对数一概率分布。然后将硫酸气溶胶在声速下抽经喷射撞击器,利用气溶胶质点惰性作用,收集微量硫酸。撞击器中有百里香蓝处理过的胶片。藉可见光线透过胶片的强度,可以分析硫酸气溶胶的数量,最低可测至0.01微克硫酸。 实验结果显示二氧化硫在高湿度(98%相对湿度)时所得光化学反应速率与低湿度时相同。这表示化学反应主要为气相反应,在液相中反应速率相对而言是很低的。二氧化氮,氯化钠核及五氧化二钒为工业区大气中常存在的杂质,经引入后,并未发生触媒作用。世界上若干工业区大气中二氧化硫在所研究情况下约需300小时中午日光照耀,可将视距减至1公里。
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