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Drones have been attracting significant attention in the field of agriculture. They can be used for various tasks such as spraying pesticides, monitoring pests, and assessing crop growth. Sensors are also widely used in agriculture to monitor environmental parameters such as soil moisture and temperature. Due to the high cost of communication infrastructure and radio-wave modules, the adoption of high-density sensing systems in agriculture is limited. To address this issue, we propose an agricultural sensor network system using drones and Optical Camera Communication (OCC). The idea is to transmit sensor data from LED panels mounted on sensor nodes and receive the data using a drone-mounted camera. This enables high-density sensing at low cost and can be deployed in areas with underdeveloped infrastructure and radio silence. We propose a trajectory control algorithm for the receiving drone to efficiently collect the sensor data. From computer simulations, we confirmed that the proposed algorithm reduces total flight time by 30 % compared to a shortest-path algorithm. We also conducted a preliminary experiment at a leaf mustard farm in Kamitonda-cho, Wakayama, Japan, to demonstrate the effectiveness of the proposed system. We collected 5178 images of LED panels with a drone-mounted camera to train YOLOv5 for object detection. With simple On–Off Keying (OOK) modulation, we achieved sufficiently low bit error rates (BERs) under 10 − 3 in the real-world environment. The experimental results show that the proposed system is applicable for drone-based sensor data collection in agriculture. [ABSTRACT FROM AUTHOR]

We construct a superfield formulation for non-relativistic Chern–Simons-matter theories with manifest dynamical supersymmetry. By eliminating all the auxiliary fields, we show that the simple action reduces to the one obtained by taking non-relativistic limit from the relativistic Chern–Simons-matter theory proposed in the literature. As a further application, we give a manifestly supersymmetric derivation of the non-relativistic ABJM theory.

Using the ambitwistor string theory, we study graviton scattering amplitudes in a light-like linear dilaton background of 10-dimensional supergravity. At the tree level, we find that the three-graviton amplitude coincides with the type-II superstring theory, and the four-graviton or more amplitudes differ from the superstring theory but satisfy the scattering equations. Due to a modified momentum conservation law different at each order in genus expansion, a nonzero amplitude is determined solely from the particular order in perturbation theory without further corrections. [ABSTRACT FROM AUTHOR]

The Nelson-Seiberg theorem dictates conditions for the spontaneous breaking of the supersymmetry in Wess–Zumino models with generic, possibly nonrenormalizable, superpotential; the existence of the R-symmetry is necessary while the spontaneous breaking of the R-symmetry is sufficient. If we restrict ourselves to generic but renormalizable theories, however, there exist Wess–Zumino models whose vacua break the R-symmetry spontaneously while preserving the supersymmetry. The classification and conditions of such renormalizable exceptions are under active study. We give some new examples of spontaneous breaking of the R-symmetry with preserved supersymmetry that are not covered in the literature. [ABSTRACT FROM AUTHOR]

Old folklore says that there is no nontrivial renormalization group fixed point with U (1) gauge symmetry in four dimensions, but it can be circumvented by the existence of magnetic monopoles. We propose to construct (potentially infinitely many) novel types of field theories with U (1) gauge symmetry by gauging U (1) × U (1) global symmetry electrically and magnetically. If the construction is consistent, the resulting theory will most likely possess a nontrivial renormalization group fixed point for the U (1) gauge coupling constant and it will be a nontrivial conformal field theory without the U (1) × U (1) global symmetry in the infrared upon tunings of other relevant deformations. If the construction is CP-violating, a renormalization of the θ -parameter is accompanied. [ABSTRACT FROM AUTHOR]

Recent studies on swampland conjectures (e.g. non-SUSY AdS conjecture or AdS distance conjecture) predict that the (lightest) neutrino must be Dirac and the mass must be cosmologically small m < c Λ cc 1 / 4 ∼ 1 0 meV. The Dirac neutrino naturally accompanies a U (1) symmetry that can be embedded in the anomaly-free U (1) B − L global symmetry of the standard model. We point out that the swampland conjectures applied to a circle compactification with the U (1) symmetry twisting lead to further constraints. In particular, the U (1) symmetry must be broken down to ℤ 4 , ℤ 8 or ℤ 1 0 in the case of normal hierarchy, and ℤ 4 in the case of inverted hierarchy, providing evidence for the absence of continuous global symmetry in quantum gravity. We also predict a more constrained upper bound of the neutrino mass for each case. [ABSTRACT FROM AUTHOR]

We show that the Wess–Zumino action for the spontaneously broken Weyl (or conformal) symmetry, a.k.a dilaton effective action, in even D dimensions can be obtained from the Kaluza–Klein dimensional reduction of the Lovelock action in D + dimensions by taking the → 0 limit, where the dilaton is identified with the metric in the extra dimension. The construction gives an explicit form of the dilaton effective action in any even dimensions. [ABSTRACT FROM AUTHOR]

We point out that the bootstrap program in quantum mechanics proposed by Han et al. reduces to a bootstrap study of a microcanonical ensemble of the same Hamiltonian in the ℏ → 0 limit. In the limit, the quantum mechanical archipelago becomes an extremely thin line for an anharmonic oscillator. For a double-well potential, a peninsula in E ≤ 0 appears. [ABSTRACT FROM AUTHOR]

The Gauß hypergeometric function shows a recursive structure which resembles those found in conformal blocks. We compare it with the recursive structure of the conformal block in boundary/crosscap conformal field theories that is obtained from the representation theory. We find that the pole structure perfectly agrees but the recursive structure in the Gauß hypergeometric function is slightly "off-shell". [ABSTRACT FROM AUTHOR]

The supersymmetric Lee–Yang model is arguably the simplest interacting supersymmetric field theory in two dimensions, albeit nonunitary. A natural question is if there is an analogue of supersymmetric Lee–Yang fixed point in higher dimensions. The absence of any ℤ 2 symmetry (except for fermion numbers) makes it impossible to approach it by using perturbative expansions. We find that the truncated conformal bootstrap suggests that candidate fixed points obtained by the dimensional continuation from two dimensions annihilate below three dimensions, implying that there is no supersymmetric Lee–Yang fixed point in three dimensions. We conjecture that the corresponding phase transition, if any, will be the first-order transition. [ABSTRACT FROM AUTHOR]

In this paper, we study anomalous hydrodynamics with a dyonic charge. We show that the local second law of thermodynamics constrains the structure of the anomaly in addition to the structure of the hydrodynamic constitutive equations. In particular, we show that not only the usual E ⋅ B term but also E 2 − B 2 term should be present in the anomaly with a specific coefficient for the local entropy production to be positive definite. [ABSTRACT FROM AUTHOR]

We investigate an alternative quantization of R-NS string theory. In the alternative quantization, we define the distinct vacuum for the left-moving mode and the right-moving mode by exchanging the role of creation operators and annihilation operators in the left-moving sector. The resulting string theory has only a finite number of propagating degrees of freedom. We show that an appropriate choice of the GSO projection makes the theory tachyon free. The spectrum coincides with the massless sector of type IIA or type IIB superstring theory without any massive excitations. [ABSTRACT FROM AUTHOR]

Access-metro convergence networks (AMCN) have been proposed as a future optical communication network to realize flexible and dynamic bandwidth allocation. An AMCN requires transceivers with different wavelengths for the optical network units (ONUs). This causes an increase in production costs. Although an all-optical wavelength converter (AOWC) mitigates this issue, the AOWC increases the installation cost because it consists of many expensive optical devices. We propose the use of a remotely pumped AOWC (RP-AOWC) with an AMCN. The proposed technique can reduce the number of pump light sources in the AOWC. This paper demonstrates this reduction in the number of light sources and the feasibility of wavelength conversion using pump light propagation. We calculate the reduction in the number of pump sources and the number of transceiver types caused by the use of RP-AOWC and experiment with the wavelength conversion using pump light propagation. [ABSTRACT FROM AUTHOR]

This paper proposes a novel return light cancellation technique using an adaptive interference equalizer in the wavelength division multiplexed passive optical network (WDM–PON) transmission system employing the single-wavelength bidirectional transmission scheme. In this scheme, the same wavelength is assigned to both the uplink and the downlink. In other words, the number of the wavelengths allocated to optical network units can be half compared with a typical PON system. However, this presents us with a problem in that the reflected component of the transmitted signal light interferes with the received signal light. We investigated the performance of the proposed interference canceling equalizer using back-to-back transmission simulation and a dual-polarization-quadrature-phase-shift-keying signal transmission experiment. The results indicated that the proposed adaptive equalizer enabled reception with no error when the OSNR was sufficiently large, even when the power of the interfering light was large (i.e., SIR $\geq$ 2 dB). [ABSTRACT FROM AUTHOR]

Device-to-device (D2D) communication is expected to be a promising solution in next generation cellular technologies to efficiently provide connectivity over a wide area at low cost. However, autonomous D2D communication introduces challenging technical issues, and how to achieve the benefit and cooperation of users is an unsolved issue. To address this problem, we propose a novel concept of a bandwidth market called Banket for building a sharing economy in mobile networks. It provides an auction-based free marketplace for mobile users to buy and sell mobile bandwidth without cooperation with network operators. The contribution of the proposed Banket is to achieve dynamic and complete autonomous D2D communication established by market mechanisms without intervention. Banket prompts users to efficiently use network resources, and consequently achieves cost reduction for network operators and social profit by reducing resource and energy consumption. The validity of the proposed auction-based transaction scheme is confirmed through computer simulations. Furthermore, the feasibility of Banket is validated with experimental results using implemented applications. [ABSTRACT FROM AUTHOR]