读书不统观首尾,不可妄下批评——读《周代乡乐考论》札记

近读李婷婷先生<周代乡乐考论>一文(载<中国文化研究>2007年夏之卷.文中简称"李文"),觉得颇有可议之处.今不揣谫陋,将若干大大小小不敢苟同之处,凡十二处,次第列出,加上拙按,幸方家有以教我.李文的问题,归纳起来,大体有以下三点.第一,"读书不统观首尾,不可妄下批评",这是陈垣先生<陈垣史源学杂文>一书中告诫后学的两句话,[1]笔者深深服膺,而纵观李文,颇有与此告诫相违者,拙文之第六、第十二条所论是也.第二,率尔操觚,贸然立论.拙文中第二、第五、第七、第十一条所论是也.第三,当简则繁,当繁则简,处置失当.例如,"何谓乡乐",这本来是一个给乡乐下定义的问题,竟然不避雷同地繁征博引五六百字,是所谓当简则繁.而所谓"郑玄、贾公彦及其后世之学者等在言及无算乐时,还将乡乐与无算乐混为一谈"这样一个大问题,本来应该多方举证,以证服人,而遗憾的是作者仅仅举了两个例子,还都不符合学术规范.梁启超说:"凡立一义,必凭证据.孤证不为定说."[2]前辈学者说:"例不十不立."诚哉斯言!     

Recent progress in the plastic methods of structural analysis

The techniques described in Part I of this paper for the calculation of plastic failure loads under proportional loading are further exemplified by indicating solutions for a rectangular building frame, a Vierendeel girder, and a shed-type portal frame. A method for estimating deflections of a frame just as the collapse load is attained is then described, with some indications as to its reliability. More general conditions of loading than proportional loading are next discussed, and generalized load and failure concepts are defined. The theorems and techniques for determining critical shakedown loads under variable, repeated loading are then described and illustrated. The relation of the elastic-plastic shakedown analysis to the much simpler analysis for failure under single load applications is discussed.     

Climate control through ionization

This paper summarizes some of the experimental evidence of the apparent biological effects produced by atmospheric ionization. Thermionic ion sources are discussed and the results of experimental determinations of their characteristics are presented.     

Frequency-coordinate vector diagram

From the standpoint of circuit synthesis as well as for a fundamental comprehension of circuit behavior, it is desirable to be able to visualize the response of a circuit over an extended frequency range by means of a geometrical construction. Mathematically, the response of a circuit can be expressed with the La Place transform theory as a function of the complex frequency variable, p = α + jωw, in which a is the decrement and ω is the “real” angular frequency. Physically, the nature of the real-frequency response is usually not discernible by casual inspection of the mathematical function. This paper develops a means of visualizing this frequency response readily through the construction of a vector diagram from the response function.