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 Formulas are derived for the solution of the transient currents of dissipative lowpass Ttype electric wave filters. Oscillograms taken by cathode ray oscillograph for dc. and ac. cases are found to agree with results calculated from these formulas. From these calculations, the following conclusions are derived. When terminating resistance is gradually increased from O, the damping constants of the sine terms begin to differ from each other, ranging in decreasing magnitude from term of the lowest frequency... Formulas are derived for the solution of the transient currents of dissipative lowpass Ttype electric wave filters. Oscillograms taken by cathode ray oscillograph for dc. and ac. cases are found to agree with results calculated from these formulas. From these calculations, the following conclusions are derived. When terminating resistance is gradually increased from O, the damping constants of the sine terms begin to differ from each other, ranging in decreasing magnitude from term of the lowest frequency to the last term of cutoff frequency. Hence the transient is ultimately of the cutoff frequency. At cutoff frequency, this constant is near to but greater than R/2L. For each increase of section, there is introduced an additional sine term with smaller damping constant. Therefore transients die out faster in filters of smaller number of sections. Since transient amplitudes are of the same order of magnitude before and after cutoff, filtering property only exists in the steady states.  此篇先推求收端加电阻时,低频滤波器瞬流之公式。依此公式算出之图与用阴极光示波器映出之曲线相符合。自推算之结果,可得下列结论: (一)在滤波器收端电阻渐加时,瞬流各项之挫率渐互异,其数量由低频项至隔阻频之项顺序渐减;其最小数仍比收端无电阻时之挫率(R/2L)为大。故瞬流终必变为隔阻频之电流;而较收端无电阻时易于消减。 (二)当滤波器增加一段时,瞬流之项数亦加一。所加项之挫率皆比前有者为小。故少段滤波器之瞬流易于消减。 (三)在隔阻频後瞬流之数量与在其前者相彷恒较隔阻频後之安定数量大数十倍,故滤波之特性仅能见之于安定状态。  Formulas are derived for the solution of the transient currents of resistanceterminated dissipative πtype lowpass, T and πtype highpass electric wave filters. Oseillograms taken by cathode ray oscillograph for dc. and ac. cases are found to agree with the results calculated from these formulas. From these calculations, the following conclusions are derived: (1) When the terminating resistance is gradually increased from 0, the damping constants of the damped sine terms begin to differ greatly from each... Formulas are derived for the solution of the transient currents of resistanceterminated dissipative πtype lowpass, T and πtype highpass electric wave filters. Oseillograms taken by cathode ray oscillograph for dc. and ac. cases are found to agree with the results calculated from these formulas. From these calculations, the following conclusions are derived: (1) When the terminating resistance is gradually increased from 0, the damping constants of the damped sine terms begin to differ greatly from each other, ranging in decreasing magnitudes from the first damped sine term to the last term of cutoff frequency. Hence the transient is ultimately of the cutoff frequency. At the cutoff frequency, this constant is greater than the corresponding constant (R/2L) when the termination is absent. (2) For each increase of one section, there is introduced an additional damped sine term with smaller damping constants. Therefore transients die out faster in filters of small no. of sections. (3) With the same network constants, the damping constants of πtype filters are greater than the corresponding values of Ttype filters. As a result, transients die out faster in πtype filters. (4) The amplitudes of the transient terms in the attenuation and transmission ranges are of the same order of magnitude, and the filtering property only exists in the steady states. (5) The cutoff frequency of the πtype filters varies with the no. of sections used. When only two sections of low, or, highpass filter are used, the variation amounts to nearly 26 per cent from the theoretical value.  此篇先推求收端加电阻时,低频与高频滤波器瞬流之公式依此公式算出之图与用阴极光示波器映出之曲线相符合。自推算之结果,可得下列结论: (一)在滤波器收端电阻渐加时,瞬流各项之挫率渐渐互异其数量,由第一挫波项至最後隔阻频项,顺序渐减;其最小数仍比收端无电阻时之挫率(约等于R/2L)为大。故瞬流终必变为隔阻频之电流,而较收端无电阻时易于消灭。 (二)当滤波器增加一段时,瞬流之项数亦加一,所加项之挫率皆比前有者为小,故少段滤波器之瞬流易于消灭。 (三)在π式滤波器中,其瞬流各项之挫率恒较同一电恒数T式滤波器中之相当项之挫率为大故在π式滤波器中,瞬流消灭较易。 (四)在隔阻频后瞬流之数量与在其前者相彷,恒较隔阻频后之安定数量大数十倍,故滤波器之特性仅能见之于安定状态之下。 (五)π式滤波器之隔阻电频随所用之段数而变化在二段之滤波器中,此变化数为最高,其数与理想之数相差百分之二十六。  Nine Marchi series of albino rats in which various points of the retina were destroyed by the method of thermocautery have been carefully studied. The courses and the terminations of the degenerated optic fibers have been determined. The results are summarized by a composite diagram (fig. 9). It shows:(1) that the fibers issuing from the upper quadrant of the retina are lying in the lateral of the optic nerve, crossed in the lower level of the chiasma passed along the medial part of the crossed optic tract and... Nine Marchi series of albino rats in which various points of the retina were destroyed by the method of thermocautery have been carefully studied. The courses and the terminations of the degenerated optic fibers have been determined. The results are summarized by a composite diagram (fig. 9). It shows:(1) that the fibers issuing from the upper quadrant of the retina are lying in the lateral of the optic nerve, crossed in the lower level of the chiasma passed along the medial part of the crossed optic tract and terminated partly in the ventral of the posterior half of the lateral geniculate body and partly in the caudolateral part of the superior colliculus;(2) that those from the lower retina are lying in the lower part of the nerve, crossed in the higher level of the chiasma, passed along the lateral border of the crossed tract, and terminated partly in the dorsal part of the anterior half of the lateral geniculate body and partly in the mediooral part of the superior colliculus;(3) that those from the temporal retina are lying in the lateral part of the nerve, crossed in the lower level of the chiasma, passing through the inner part of the tract and terminated partly in the medial part of the lateral geniculate body and partly in the lateral part of the superior colliculus;(4) that those from the nasal retina are lying in the medial of the nerve, crossed in the higher level of the chiasma, passing through the outer border of the tract and terminated partly in the lateral part HSIANGTUNG CHANGof the anterior half of the geniculate body and partly in the medial part of the superior colliculus;(5) that those from the peripheral margin of the temporal retina are lying in the lateral half of the nerve, uncrossed in the chiasma, passing through the upper half of the tract, terminated in the central part of the geniculate body and never reached the superior colliculus; and(6) that the anterior and posterior accessory optic tracts composed probably of the collaterals of the crossed optic neurons are traced to the corpus Luysii and the nucleus opticus tegmenti respectively.(7) that the optic fibers also terminate in the pretectal nucleus of the thaIamus.  本實驗曾將九隻白鼠之視網膜的各處用電燒法加以毁壞,然後用马基氏染色法(Marchi's method)製成連續切片,详加研究,以斷定其枯萎的神经纖维所经之路徑及终止之點。 實驗结果如下: (一) 自網膜上部發出之神经纖維,位於視神经之外侧,由視神经叉之近尾段跨越於對面,又经對邊視神经通路之内側部,而一部终止於背外側膝體之后腹部,一部终止於上叠體之外侧部。 (二) 自網膜下部發出之纖維,位於視神经之下侧,由視神经叉之近首段跨越於對邊,再沿對邊視神经通路之外侧進行,而一部终止於背外側膝體之前背部,一部终止於上叠體之前内側部。 (三) 自網膜外侧部發出之纖维,位於視神经之外侧部,由視神经叉之近尾段跨越於對面,再沿對邊視神经通路之内側部進行,而一部终止於背外側膝體之后内側部,一部终止於上叠體之外側部。 (四) 自網膜内側部發出之纖维,位於视神经之内側,由视神经叉之近首叚跨越於對面,再经對邊視神经通路之外邊,而一部终止於背外側膝體之前外側部,一部终止於上叠體之内側部。 (五) 自網膜之外側邊緣部發出之纖维,位於视神经之外側,不到對邊,经本邊視神经通路之下半部而终止於背外侧膝體之中央。無及於上叠體... 本實驗曾將九隻白鼠之視網膜的各處用電燒法加以毁壞,然後用马基氏染色法(Marchi's method)製成連續切片,详加研究,以斷定其枯萎的神经纖维所经之路徑及终止之點。 實驗结果如下: (一) 自網膜上部發出之神经纖維,位於視神经之外侧,由視神经叉之近尾段跨越於對面,又经對邊視神经通路之内側部,而一部终止於背外側膝體之后腹部,一部终止於上叠體之外侧部。 (二) 自網膜下部發出之纖維,位於視神经之下侧,由視神经叉之近首段跨越於對邊,再沿對邊視神经通路之外侧進行,而一部终止於背外側膝體之前背部,一部终止於上叠體之前内側部。 (三) 自網膜外侧部發出之纖维,位於視神经之外侧部,由視神经叉之近尾段跨越於對面,再沿對邊視神经通路之内側部進行,而一部终止於背外側膝體之后内側部,一部终止於上叠體之外側部。 (四) 自網膜内側部發出之纖维,位於视神经之内側,由视神经叉之近首叚跨越於對面,再经對邊視神经通路之外邊,而一部终止於背外側膝體之前外側部,一部终止於上叠體之内側部。 (五) 自網膜之外側邊緣部發出之纖维,位於视神经之外側,不到對邊,经本邊視神经通路之下半部而终止於背外侧膝體之中央。無及於上叠體者。 (六) 前副視神经通路,终止於路易斯氏體(Corpus Luysii),而后副视神经通路則终止於视底巢(   << 更多相关文摘 
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