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5) The behavior of DouGong and Joggle joint of Chinese ancient wooden structure.


Change in the power of EEG activity in the α range in response to tonic nociceptive stimulation of the distal joint of the littl


Examination of 12 healthy volunteers aged 2056 years was performed to study the EEG changes caused by a tonic squeeze of the distal joint of the little finger of the left and then the right hand.


Sound radiation from a joint of plates of different thickness


A number of data acquistion and processing systems developed and produced at the Joint of Institute of Nuclear Research in order to implement the infrared synchrotronaccelerator diagnostics are described.

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 The socalled "truss rigid frames" are those rigid frames with trusses as their horizontal beams, of which the two ends are rigidly connected to columns. Within the author's knowledge, all the methods available at present for analyzing such rigid frames are based on Certain special assumptions such as (1) that the positions of the points of contraflexure in all the columns are previously known; (2) that the end rotations of a truss may be reprensented by that of its assumed line of axis as in the case of an... The socalled "truss rigid frames" are those rigid frames with trusses as their horizontal beams, of which the two ends are rigidly connected to columns. Within the author's knowledge, all the methods available at present for analyzing such rigid frames are based on Certain special assumptions such as (1) that the positions of the points of contraflexure in all the columns are previously known; (2) that the end rotations of a truss may be reprensented by that of its assumed line of axis as in the case of an ordinary beam; or (3) that the end verticals of trusses may be given certain prescribed deformations. Of course, the adoption of any of such assumptions leads to only approximate results inconsistent with the actual deformations of such rigid frames under any loading. Heretofore, the author did not know any correct method for analyzing such rigid frames. In this paper, the author presents two principles of the correct analysis of truss rigid frames. The first principle is that of "moment action on column" for computing the angle change constants of columns, and the second principle is that of "effect of spanchange in truss" for computing the angle and span change constants of trusses.As, for computing the angle change constants of a truss, the dummy unit moment is a couple applied to its end verticals, so, for computing the angle change constants of a column, the dummy unit moment must also be a couple applied to the section of column rigidly connected to the end of a truss, in order to effect a consistent deformation at the joint of the two. This is the first principle.A truss just like a curved or gabled beam of which the effect of spanchange can not be neglected, so truss rigid frames belong to the same category of what may be called "spanchange" rigid frames such as rigid frames with curved or gabled beams. Therefore the spanchange constants of trusses should be included besides their anglechange constants for analyzing truss rigid frames. This is the second principle.With the constants of columns and trusses are all computed in accordance with respectively the first and second principles mentioned above, truss rigid frames may be analyzed by any method including the effect of spanchange as in the case of rigid frames with curved or gabled beams, and the results thus obtained will be exactly the same as by the method of least work or deflections without any special assumptions.In this paper, after the two principles are described and the formulas for computing the constants of columns and trusses are derived, the correctness of the two principles are then proved by the methods of least work, deflections and slopedeflection. A twospan truss rigid frame is analyzed under the following three conditions:Ⅰ. Applying both of the two principles to obtain the correct results.Ⅱ. Applying only the first principle to show the discrepancies of neglecting the effect of spanchange in trusses as born out by comparing the results of Ⅱ with Ⅰ.Ⅲ. Applying neither of the two principles, and the truss rigid frames being analyzed by the special assumption (2) mentioned above with the line of axis at the bottom chord of truss, in order to show the discrepancies of neglecting the moment action on column as born out by comparing the results of Ⅲ with Ⅱ. For the sake of brevity, only the results are given in Tables 1 to 5 without computations in details.Although the discrepancies of neglecting the moment acticn on column are only slight as shown by comparing the results of Ⅲ with Ⅱ in Tables 2, 4 and 5, there is no reason why special assumptions should not be replaced by the correct principle of moment action on column to obtain correct results. As shown by comparing the results of Ⅱ with Ⅰ in Tables 2, 4 and 5, the discrepancies by neglecting the span change in trusses are generally considerable and, in certain particular part, as large as 3000%. Therefore, for the safe and economical design of truss rigid frames, the effect of spanchange in trusses should not be neglected in their analysis.Finally, for analyzing co  所謂“桁架剛構”即以桁架為横梁与柱相剛接之剛構。現下採用分析剛構之任一方法,以分析此項剛構时,均須採用種種特殊之假定而得近似之結果。據著者所知,中外書刊中似尚无此項剛構之正確分析法。於本文中,著者發表关於桁架剛構正確分析之兩項原理,即柱頂力矩作用与桁架跨变影響之兩项原理。前項原理使柱頂段之角夔与桁架端豎桿相同,以符合柱与桁架剛接处之連续性。後項原理指出桁架与曲梁(即拱)及折梁(即山墙式梁)相同係一種“跨变横梁”,故桁架刚構亦与拱式及山墙式剛構相同,係一種“跨变剛構”。若根據此兩项原理,分别计算柱与桁架兩端的撓曲常数,再用分析跨变刚構之任一分析法以分析此項刚構,則所得之枯果,与不作任何特殊假定用最少功法或变位法所得者完全相同。本文先說明此兩项原理及根據此兩項原理计算柱与桁架撓曲常數之方法。次取一最簡單之桁架刚構为例,證明此丙項原理之正確性。桁架刚構既与拱式及山墙式刚構同属於跨变刚構一類型,分析後者之任何方法均可用以分析前者,本文无須贅述。但取一兩跨之桁架刚構為例,列举所得之正確結果,与用近似法所得者相比较,藉以顯出近似法有相當巨大之差誤。關於階形之複式桁架刚構之分析,本文用“代替桁架”之辦法,但只說明其原則,不... 所謂“桁架剛構”即以桁架為横梁与柱相剛接之剛構。現下採用分析剛構之任一方法,以分析此項剛構时,均須採用種種特殊之假定而得近似之結果。據著者所知,中外書刊中似尚无此項剛構之正確分析法。於本文中,著者發表关於桁架剛構正確分析之兩項原理,即柱頂力矩作用与桁架跨变影響之兩项原理。前項原理使柱頂段之角夔与桁架端豎桿相同,以符合柱与桁架剛接处之連续性。後項原理指出桁架与曲梁(即拱)及折梁(即山墙式梁)相同係一種“跨变横梁”,故桁架刚構亦与拱式及山墙式剛構相同,係一種“跨变剛構”。若根據此兩项原理,分别计算柱与桁架兩端的撓曲常数,再用分析跨变刚構之任一分析法以分析此項刚構,則所得之枯果,与不作任何特殊假定用最少功法或变位法所得者完全相同。本文先說明此兩项原理及根據此兩項原理计算柱与桁架撓曲常數之方法。次取一最簡單之桁架刚構为例,證明此丙項原理之正確性。桁架刚構既与拱式及山墙式刚構同属於跨变刚構一類型,分析後者之任何方法均可用以分析前者,本文无須贅述。但取一兩跨之桁架刚構為例,列举所得之正確結果,与用近似法所得者相比较,藉以顯出近似法有相當巨大之差誤。關於階形之複式桁架刚構之分析,本文用“代替桁架”之辦法,但只說明其原則,不列出公式及算例。  Many methods of analyzing statically indeterminate structures are now available. The method of redundant forces and that of deformations (i. e. the slopedeflection method), heretofore generally used in the U. S. S. R., both require the solution of a system of simultaneous simple equations. In the case of multistorey and multibay bents, the large number of such equations would greatly complicate the calculation work, it being both timeconsuming and liable to make mistakes. The method of moment distribution... Many methods of analyzing statically indeterminate structures are now available. The method of redundant forces and that of deformations (i. e. the slopedeflection method), heretofore generally used in the U. S. S. R., both require the solution of a system of simultaneous simple equations. In the case of multistorey and multibay bents, the large number of such equations would greatly complicate the calculation work, it being both timeconsuming and liable to make mistakes. The method of moment distribution simplifies calculations to a great extent, as there is no need to solve simultaneous equations, and therefore it has been warmly received bY practical engineers. Many soviet scholars are also devoted to its study. There are, however, defects in this method, namely: (1) Should the moments obtained in the successive cycles of distribution and carryingover prove to converge very slowly, twenty or more such cycles must be done if fairly accurate results are expected.(2) In the case of analyzing structures under various conditions of loading, while it is possible to find the influence moments by applying a unit moment at each joint as proposed by Prof. Hardy Cross, it would bequite laborious in the case of multistorey and multibay bents containing a large number of members, especially when subjected to unsymmetrical loadings.For the remedy of the first defect, such Chinese scholars as Profs. Lin Tung Yen, Chao Tsu Wu, Meng Chao Li and Tsai Fang Yin have made much contribution, and the author of this paper has recently written a discussion on the two papers of the lastmentioned scholar. For the remedy of the second defect, the author is unaware of any except that mentioned below.One of the soviet scholars, Dr. P. P. Shaggin (i.e.) has suggested important improvements with regard to both these defects. For the former, he adopted a method of singlecycle distribution; and for the latter, he invented the method of successive conjugation which greatly reduces the work of calculation in finding the influence moments. The essence of these methods is wellworth studying on the part of our Chinese engineers. After an intensive study, the author of this paper thinks that, while Dr. Shaggin's methods are quite correct in principle, his methods of calculation can still be somewhat improved, as described herein, so as to be made more easily applied in practice.This paper Shaggin based upon the book, (Calculation of Multistorey Frames by the Method of Successive Conjugation) published in 1954 by Dr. P. P. Shaggin in Leningrad, U. S. S. R., shows that, in applying a unit moment at each joint of a given statically indeterminate structure, one can easily find the influence moments at the ends of all the members, and that, after multiplying the unbalanced fixedend moments at each joint calculated in accordance with the given external loads, by the respective influence moments, the sum of such products added to the original fixedend moments will give at once the actual moments at each end of the members in the structure.Three notable improvements are indicated in this paper:(1) Dr. Shaggin's formula (5") on page 11 of his book, has been altered to formulas (3) in this paper. (2) For multistorey bents, Dr. Shaggin's method of finding the conjugate moments (i. e. the influence moments) by formulas is replaced by the usual method of simple momentdistribution.(3) The author of the paper has extended the method to the analysis of multistorey and multibay bents under any system of unsymmetrical loading.Of course, for structures under a single system of loading, influence moments need not be found and, generally speaking, it would be more convenient to apply the original method of momentdistribution; for a multistorey bent, it would be better, even in this case, to modify it by applying the method of successive conjugation.The author is of the opinion that the application of the methods described in this paper, being convenient and timesaving, would be useful to the practical engineers.  本文以蘇聯學者沙金博士最近出版之“用逐次互聯法計算多層排架”一書为依據,叙述在已知超靜定結構中每一結點,施以單位力矩,可以很容易地求得各桿端的影響力矩;然後依照其所受外力荷載,求得各結点處的定端力矩,分別乘以相當的影響力矩,相加之後並加以原有的定端力矩,即得各該桿端的實際力矩。若結構承受多種多样的荷載(不問其為豎向的或平向的、對稱的或不對稱的),用此篇所述之方法以推算各桿端力矩,著者認為最便利、最省時,並且適合實際工作者之需要。  In the present paper three species of Lamproglena are reported with two nauplius larvae belonging to Lamproglena chinensis and L. carassii.1. Nauplius larva of Lamproglena chinensis (fig. 11)The larva is pyriform or ovoid in outline, with a sharp process at its posterior end. The body is slightly transparent, measuring 0.209 mm in its total length and 0.125 mm in the greatest width. The yolk spherules are small and numerous. There are three pair of appendages. First antenna has two joints and bears three setae.... In the present paper three species of Lamproglena are reported with two nauplius larvae belonging to Lamproglena chinensis and L. carassii.1. Nauplius larva of Lamproglena chinensis (fig. 11)The larva is pyriform or ovoid in outline, with a sharp process at its posterior end. The body is slightly transparent, measuring 0.209 mm in its total length and 0.125 mm in the greatest width. The yolk spherules are small and numerous. There are three pair of appendages. First antenna has two joints and bears three setae. Second antenna is biramus: exopod singlejointed and with three setae at terminal end; endopod possessing three joints and bearing four setae. Mandible is also biramus; exopod possessing three joints and endopod only one joint. The posterior end has a pair of setae functional as balancers.2. Lamproglena orientalis Markewitsch, 1936 (figs. 110)The female specimen is parasitic on the gills of Erythroculter erythropterus (Nanking, Wushin), E. recurviceps (Nanking), E. dabryi (Shanghai, Soochow), Culter albernus (Shanghai, Wushi) and C. brevicauda (Shanghai, Soochow and Wushi).The body is cylindrical, somewhat depressed, being 1.71 to 2.60 mm in total length. The abdomen is without segmentation, the length of the abdomen varying from 0.27 to 0.34 mm in length. The caudal ramusis fingershaped and without any processes.Antennae are present. Mandible (formerly called first maxilla)is "S"shaped, with small teeth at its terminal end. A hooklike spine present at the terminal end of first maxilla (formerly called second maxilla). The maxillipeds are not far away from the mouth parts, and possess three hooklike spines at the terminal end. Fives pairs of swimming legs are present. The basipodites of the 14 legs each bears a seta. For seta formula of this species see figures 6 to 10.3. Lamproglena carassii Sproston et al., 1950.The female specimen is found on the gills of Carassius auratus taken from Nanking, Wushi. This species differs from the type specimen in the following particulars:(1) The terminal end of the abdomen is not pointed.(2) A seta present on the basipodite of the first to fourth legs.(3) A seta on the second joint of the exopod of the fourth leg.Nauplius larva of Lamproglena carassii (fig. 24).Body is ovoid in shape, measuring 0.327 mm in length by 0.137 mm in width. The yolk spherules are less numerous than those found in the nauplius larva of L. chinensis. There are three pairs of appendages, as found in the nauplius larva of L. chinensis. The exopod of its mandible possesses four joints instead of only 3, as in L. chinensis.  (1)这次在南京至上海一带从淡水魚的鳃上共获得了3种狹腹鳋(中华狹腹鳋、东方 狹腹鳋和鯽狹腹鳋),并对中华狹腹鳋和鯽狹腹鳋的无节幼体也加以補充描述。 (2)从这次所得的东方狹腹鳋來看,腹部的长度存在着明显的变异,又增添五种新宿主鱼。 (3)本文对鯽狹腹鳋的特徴,有新的補充和修正。   << 更多相关文摘 
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