Development of Novel Cicada-Resistant Optical Drop Cable

Dead-twig discrimination for oviposition in a cicada, Cryptotympana facialis (Hemiptera: Cicadidae)

“…Rather, dead-twig discrimination seems more likely to be accomplished by sensing the absence of evidence that twigs are alive, for the following two reasons. First, C. facialis females frequently attempt oviposition into various artificial substrates that lack both live and dead plant cues, such as paper poles and cables sheathed with rubber and resinous materials (Tsukamoto et al 2008(Tsukamoto et al , 2010M. Moriyama, personal observation).…”

“…Therefore, two possible mechanisms, which are not mutually exclusive, may be involved in this discrimination phase in cicadas: 1) plant chemicals released during boring are sensed using sensillum-bearing organs adjacent to the ovipositor, and 2) physical properties of substrates are sensed through the ovipositor. Experiments using artificial cables that are coated with resins having various physical properties have revealed that elastic or hard substrates decrease the depth of boring injuries by C. facialis females and inhibit the subsequent egg laying process (Katsuya 2007;Tsukamoto et al 2010). Therefore, at least the physical properties of substrates are likely to influence the decision of egg laying.…”

“…Recently, extensive domination of this species in urban areas, which is associated with loss of cicada diversity, has become a new social problem in Japan Numata 2011, 2015;Takakura and Yamazaki 2007). In fact, heavy infestation of C. facialis in residential areas causes breakdown of optical fiber cables due to piercing with the cicadas' ovipositor (Cyranoski 2007;Tsukamoto et al 2008Tsukamoto et al , 2010). In the first step to understand how cicada females discriminate dead twigs from live twigs, we observed behaviors of C. facialis females that were experimentally hung on dead or live plant material, and analyzed the behavioral sequence leading toward oviposition.…”

Development of a Handheld Optical Fusion Splicer with a Wing Sleeve Optical Connector

“…Figure 5 shows the configuration diagram of the fusion-spliced wingtype ferrule optical connector head between an existing product (a) and our new design (b). Next, after fusion splicing the optical connector head and the optical drop cable [18], a cable boot is designed to strongly stabilise the optical connector head and the jacket of the optical drop cable. The designed cable boot directly connects the frame of the connector head to the jacket of the optical drop cable.…”

“…To achieve this, a lift/lower function for the fusion splice module is developed to allow the wing sleeve to be folded into the splice module. As shown in Figure 7b, the size and weight are reduced by using only one camera module, Next, after fusion splicing the optical connector head and the optical drop cable [18], a cable boot is designed to strongly stabilise the optical connector head and the jacket of the optical drop cable. The designed cable boot directly connects the frame of the connector head to the jacket of the optical drop cable.…”