111,058 research outputs found
Kojima-1Lb is a mildly cold Neptune around the brightest microlensing host star
No full textWe report the analysis of additional multiband photometry and spectroscopy and new adaptive optics (AO) imaging of the nearby planetary microlensing event TCP J05074264+2447555 (Kojima-1), which was discovered toward the Galactic anticenter in 2017 (Nucita et al.). We confirm the planetary nature of the light-curve anomaly around the peak while finding no additional planetary feature in this event. We also confirm the presence of apparent blending flux and the absence of significant parallax signal reported in the literature. The AO image reveals no contaminating sources, making it most likely that the blending flux comes from the lens star. The measured multiband lens flux, combined with a constraint from the microlensing model, allows us to narrow down the previously unresolved mass and distance of the lens system. We find that the primary lens is a dwarf on the K/M boundary (0.581 +- 0.033 MO) located at 505 +- 47 pc, and the companion (Kojima-1Lb) is a Neptune-mass planet (20.0 +- 2.0 MO) with a semimajor axis of 1.08+0.62-0.18 au. This orbit is a few times smaller than those of typical microlensing planets and is comparable to the snow-line location at young ages. We calculate that the a priori detection probability of Kojima-1Lb is only ~35%, which may imply that Neptunes are common around the snow line, as recently suggested by the transit and radial velocity techniques. The host star is the brightest among the microlensing planetary systems (Ks = 13.7), offering a great opportunity to spectroscopically characterize this system, even with current facilities.</p
A polynomial algebraic approach to Lyapunov stability analysis of higher-order 2D systems
No full textWe introduce a four-variable polynomial matrix equation which plays an essential role in the stability analysis of discrete 2-D systems and in the computation of Lyapunov functions for such systems; we call this the 2-D polynomial Lyapunov equation (2-D PLE). We also give necessary and sufficient conditions for the stability of "square" 2-D systems based on solutions of the 2-D PLE satisfying additional properties
Lyapunov stability analysis of higher-order 2D systems
No full textWe prove a necessary and sufficient condition for the asymptotic stability of a 2D system described by a system of higher-order linear partial difference equations. We show that asymptotic stability is equivalent to the existence of a vector Lyapunov functional satisfying certain positivity conditions together with its divergence along the system trajectories. We use the behavioral framework and the calculus of quadratic difference forms based on four-variable polynomial algebra
Lyapunov stability analysis of higher-order 2-D systems
No full textWe give necessary and sufficient conditions, based on the existence of a Lyapunov functional, for the asymptotic stability of a square autonomous 2-D behavior in the sense of Valcher
Parapolybia flava Saito-Morooka, Nguyen & Kojima, sp. nov.
No full text<i>Parapolybia flava</i> Saito-Morooka, Nguyen & Kojima, sp. nov. <p>(Figs 41–52, 80, 86)</p> <p> <i>Parapolybia indica indica</i> (?): van der Vecht 1966: 29, part.</p> <p> <b>Diagnosis.</b> This species can be distinguished from other species of the <i>P. i n di ca</i> species-group by the combination of the following characters: female gena well developed, swollen posterolaterally; in both sexes, T2 distinctly concave on both sides of median line.</p> <p> <b>Type material.</b> HOLOTYPE: ♀, VIETNAM: Thanh Cong, Nguyen Binh, Cao Bang Prov., 22°32.5'N, 105°52'E, 700 m, 7.viii.2012, J. Kojima & H. Nugroho, nest# VN-NE2012-Pp-10” [IUNH, long-term loan from IEBR], PARATYPES: VIETNAM: Cao Bang: 7 ♀ 2 ♂ [IUNH], Thanh Cong, Nguyen Binh, J. Kojima & H.</p> <p>Nugroho, [5 ♀ 2 ♂, 22°32.5'N, 105°52'E, 700 m, 7.viii.2012, nest# VN-NE2012-Pp-10; 3 ♀, 22°34'N, 105°52.5'E, 1000 m, 9.viii.2012, nest# VN-NE2012-Pp-11]; 6 ♀ [IUNH], Nguyen Binh, Thanh Cong, J. Kojima, H. Nugroho & IED-c [4 ♀, 22°34'N, 105°53'E; 1 ♀, 22°32.5'N, 105°52'E]; Bac Kan: 4 ♀ 1 ♂ [IUNH], Na Ri, 22°12'51''N, 105°58'42''E, 550 m, 5.viii.2012, J. Kojima & H. Nugroho, nest# VN-NE2012-Pp-09; Ha Tinh: 700 m, 30.v.2004, L.T.P. Nguyen.</p> <p> <b>Description.</b> FEMALE. Body length 15.0–18.0 mm; fore wing length 14.0– 15.5 mm. Head in frontal view 1.1 × as wide as high (Fig. 41). Gena developed, swollen laterally, in frontal view of head visible in its entire height (Fig. 41), in lateral view about as wide as eye (Fig. 42). Ocelli close to each other (Fig. 43); distance between anterior and posterior ocelli shorter than Od; POD less than their Od; anterior ocellus diameter 0.20–0.24 mm, posterior ocellus diameter 0.20–0.24 mm; OOD 2.0 × as large as Od. Propodeum finely and shallowly striate in anterior half, deeper posteriorly. T1 posteriorly swollen (4.0–5.0 mm long, Figs 44–45), 3.0 × longer than the maximum height, 3.0 × as long as its own maximum width. T2 distinctly depressed sublaterally (Fig. 46).</p> <p> <i>Color.</i> Body yellow (Fig. 80), with following parts brown to dark brown: dorsal part of scape, pedicel, basal half of flagellum (varying between individuals), paired ill-defined spots on clypeus, frons, vertex, anterior spot and line along posterodorsal margin of pronotum, median longitudinal band of mesoscutum, scutellum, tegula, median longitudinal band of propodeum, anterodorsal half of T1, anterior half of S1, S2–S6 except for dorsal yellow markings (remarkably varying in size and shape), basal spot of mid and hind femerora, basal half of mid and hind tibiae. Following parts black: anterior margin of clypeus, teeth of mandible, margin of ocelli, anterior margin and posterior line of mesoscutum, groove of mesopleuron, mid and hind tarsi.</p> <p>MALE. Body length about 13.0 mm; fore wing length 12.0 mm. Head in frontal view 1.1 × higher than wide (Fig. 47). Eye enlarged. Ocelli close to each other (Fig. 48); distance between anterior and posterior ocelli less than half of Od; POD about half of their Od; anterior ocellus diameter 0.24–0.26 mm, posterior ocellus diameter 0.22– 0.24 mm; OOD 1.3 × as Od. Antenna thin and long, F11 2.0 × as long as F10. T1 not robust (about 3.5 mm, Figs 49–50), 3.0 × longer than its maximum height, 3.0 × as long as its own maximum width. T2 distinctly depressed sublaterally (Fig. 46). Legs thin and long, hind tibia 4 mm. Volsella elongate. Digitus broadly bulged, strongly bend inward. Parameral spine short, with dense hairy setae (Fig. 51). Proximal margin of aedeagus ventrally produced (Fig. 52).</p> <p> <i>Color.</i> Body light yellow (Fig. 80); following parts light brown to orange: mesoscutum and scutellum; following parts brown to dark brown: dorsal part of scape, pedicel, dorsal side of flagellum (darker basally), frons, vertex, anterial mark and dorsolateral line of pronotum, median line and anterior margin of mesoscutum, median line of scutellum, median and dorsolateral lines of propodeum, groove on mesopleuron, dorsal mark of T1, T2 except for paired large yellow spots, tarsi.</p> <p> <b>Etymology.</b> The specific name originates from a Latin <i>flavus</i> with reference to the body coloration.</p> <p> <b>Distribution.</b> Vietnam (North Vietnam).</p>Published as part of <i>Saito-Morooka, Fuki, Nguyen, Lien T. P. & Kojima, Jun-Ichi, 2015, Review of the paper wasps of the Parapolybia indica species-group (Hymenoptera: Vespidae, Polistinae) in eastern parts of Asia, pp. 215-235 in Zootaxa 3947 (2)</i> on pages 225-227, DOI: 10.11646/zootaxa.3947.2.5, <a href="http://zenodo.org/record/232726">http://zenodo.org/record/232726</a>
The changing interpretations of the flying geese model of economic development
No full textThe flying geese model, a theory of industrial development in latecomer economies, was developed in the 1930s by the Japanese economist Akamatsu Kaname (1896–1974). While rarely known in western countries, it is highly prominent in Japan and seen as the main economic theory underlying Japan’s economic assistance to developing countries. Akamatsu’s original interpretation of the flying geese model differs fundamentally from theories of western origin, such as the neoclassical model and Raymond Vernon’s product cycle theory. These differences include the roles of factors and linkages in economic development, the effects of demand and supply, as well as the dynamic and dialectical character of Akamatsu’s thinking. Later reformulations of the flying geese model, pioneered by Kojima Kiyoshi, attempt to combine aspects of Akamatsu’s theory with neoclassical thinking. This can be described as the “westernization” of the flying geese model. It is this reformulated interpretation that has become popular in Japan’s political discourse, a process that might be explained by the change in Japan’s perspective from that of a developing to that of an advanced economy. The position taken by Japan in its recent controversy with the World Bank, however, shows that many basic elements of Akamatsu’s thinking are still highly influential within both Japan’s academia and its government and are therefore relevant for understanding current debates on development theory
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Eusynnada canariumi Kojima, Ayri & Ramamurthy, 2016, sp. nov.
No full text<i>Eusynnada canariumi</i> sp. nov. <p>(Figs. 3, 4, 7, 8, 13, 24–30)</p> <p> <b>Description.</b> Male. Length: 4.4–4.8 mm; width: 1.9–2.0 mm.</p> <p> Male. Very similar to <i>E. plaxioides</i> except derm concolorous reddish brown except antennae and tarsi slightly paler; rostrum slightly shorter than pronotum (9: 10); antennae inserted at middle in female; prothorax 1.3 times as wide as long; elytra 1.6 times as long as wide; front tibiae slightly dentate ventrally near apex; aedeagal body truncate at caudal margin, apodemes short, about 1/3 of aedeagal body.</p> <p>Female. Resembles male except rostrum longer than pronotum (13–15: 10); antennae inserted at middle of rostrum.</p> <p> <b>Type series.</b> Holotype: male, Doi Suthep-Doi Pui, Thailand, 4–7.vii.1995, H. Kojima (TUA). Paratypes, 3 males and 2 females, same data as the holotype; 1 male and 5 females, Port Blair, S. Andaman, India, 16.xii.1991, Venna (NPC) [teneral].</p> <p> <b>Etymology.</b> This species is named after the plant genus <i>Canarium</i> on which weevils were collected.</p> <p> <b>Biology.</b> Weevils were collected from <i>Canarium euphyllum</i> Kurz. (Burseraceae) on Andaman Island. Weevils were also captured on a flowering tree probably belonging to <i>Neolamarckia</i> sp. (Rubiaceae) in Thailand by using an insect net with a long handle, which is about 6 m in length.</p> <p> <b>Distribution.</b> Andaman Island (India), Thailand.</p> <p> <b>Comment.</b> This new species is easily separable from the type species by the coloration.</p>Published as part of <i>Kojima, Hiroaki, Ayri, Shaloo & Ramamurthy, V. V., 2016, Eusynnada, a resurrected genus of Ochyromerina (Coleoptera: Curculionidae: Curculioninae: Tychiini), with description of a second species from India and Thailand, pp. 469-476 in Zootaxa 4066 (4)</i> on pages 474-475, DOI: 10.11646/zootaxa.4066.4.7, <a href="http://zenodo.org/record/270556">http://zenodo.org/record/270556</a>
Comparative Study of Judicial Administration
No full textDescription of an international project directed by Takeshi Kojima (Chuo University) with the assistance of Professor Frederick H. Zemans (Osgoode Hall Law School)
Amystax urara Kojima and Yoro 2020, sp. nov.
No full textAmystax urara Kojima and Yôro, sp. nov. http://zoobank.org/ urn:lsid:zoobank.org:act: D4A26A9A-BEC8-495C-9CCC-0854A2978384 (Figs. 1–11 & 13–17) Description. Male. Length: 5.8–7.0 mm (including rostrum); width: 2.0– 2.4 mm. Brownish to blackish brown; antennae and legs reddish to brownish black; scaling variable (Figs. 1–4 & 6–8), dense, scales ovate to circular, grayish brown to ash green with metallic shimmer (or luster); pronotum with stripes; elytra with transverse band behind middle between third intervals, sometimes band indefinite; underside with only hair-like scales. Head 1.4 times as wide as rostrum; rostrum 1.2 times as long as wide, widest and weakly depressed at base, with faint marginal carina at epistome; postmentum with pair of long setae at middle; eyes moderately convex, exterior contour in dorsal aspect angled about 45º at junction to basal side of rostrum. Pronotum 1.3–1.4 times as wide as head, nearly as wide as long, widest slightly before middle, weakly arcuate at sides; disc wrinkled, without granules or median furrow. Scutellum triangular, bare. Elytra 1.6–1.7 times as long as wide, widest at basal fifth, neither costate across basal margin nor sinuate at side margin; intervals flat, with row of subrecumbent decurved scale-like setae, each slightly longer than one scale on dorsum and becoming longer, inclined on declivity; striae weakly punctate, each puncture filled with lanceolate scale. Terminalia as illustrated (Figs. 13–16); aedeagal body nearly as long as apodeme, with apical part tapered and attenuate apically; flagellum very long, longer than total length of aedeagus. Female. Length: 5.7–6.5 mm (including rostrum); width: 2.2–2.3 mm. Differs from the male by the following points: scaling denser, stripes of pronotum and band of elytra often indefinite; and elytra 1.5–1.6 times as long as wide. Spermatheca (Fig. 14) rather large, about 0.5 mm in length α, ramus and collum not differentiated and very short. Type material. Holotype male, Nageishidaira (1,700 m a.s.l.), Yakushima Is., Kagoshima Pref., 10.VI.– 12.VIII.2019, H. Kojima. Paratypes: 6 males and 8 females, same data as the holotype (all TUA). Distribution. Japan (Kyushu: mountainous area on Yakushima Island). Etymology. “Urara” means beautiful things in Japanese, and is also the name of our close associate on Yakushima Island, Mrs. Urara Ogata of the Riverside Café Bar, St. Pote. The brownish gray to ash green lustrous scales of this species make it the brightest species in the genus Amystax. Biology. Adults were found on the leaves of Pieris japonica var. yakushimensis T. Yamaz. and Buxus microphylla var. japonica (Müll. Arg. ex Miq.) Rehder et E.H.Wilson from June to the middle of August. They were not found in October at the type locality. Adults are common in July and their feeding scars were observed on leaf margins of the aforementioned shrubs (Figs. 9 & 10). The microhabitat of this weevil seems to be restricted to shrubs on nearly flat or gently sloping areas at the type locality; no adults were found on shrubs on slopes. The type locality, Nageishidaira, is a relatively flat, rocky site, ca. 1,700 m a.l.s, with low-growing shrubs such as R. yakushimanum, P. japonica var. yakushimensis, Buxus microphylla var. japonica (Tsuge in Japanese; Buxaceae), etc. Weevils appeared to associate with, not only P. j. var. yakushimensis, but also B. m. var. japonica. Remarks. The new species can easily be separated from other congeners, including the recently described Amystax yakushimanus Nakamura and Morimoto, 2015, by the following key. 1(2) Scales grayish brown to ash green with metallic shimmer. Rostrum with rather shallow transverse depression at base. Pronotum reticulate and without granules on disc. Elytra neither costate nor depressed along basal margin; striae weakly punctate, each puncture with lanceolate scale (Fig. 11). Underside clothed with only hair-like scales.................. A. urara sp. nov. 2(1) Scales grayish, pale ochraceous or brownish, usually without metallic shimmer. Rostrum with more or less distinct transverse depression at base. Pronotum granulate on disc. Elytra costate along basal margin and shallowly depressed along hind margin of costa; striae coarsely punctate, each puncture with broad ovate scale (Fig. 12). Underside densely clothed with ovate scales........................................................................ A. yakushimanus and other congenersPublished as part of Kojima, Hiroaki & Yôro, Takeshi, 2020, A new species of Amystax Roelofs, 1873 endemic to the mountainous area of the Yakushima World Natural Heritage site, Kyushu, Japan, pp. 495-500 in Zootaxa 4732 (3) on page 496, DOI: 10.11646/zootaxa.4732.3.12, http://zenodo.org/record/366718
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