National Defense Academy of Japan

Why do leaders sometimes pursue aggressive policies driven by outrage rather than by rational calculation? Although anger has long been recognised in international relations as a source of conflict, existing accounts under-theorise its causal impact on state behaviour and overlook insights from evolutionary psychology. Drawing on recalibrational theory, I develop outrage balancing, a new theory of aggressive foreign policy, defined as an anger-driven response to perceived injustice whereby leaders adopt punitive policies to recalibrate an adversary’s disregard for their welfare. I specify the conditions under which outrage arises and demonstrate how it produces disproportionate, risk-prone, and morally framed foreign policies that diverge from rational expectations. As a plausibility probe, the article re-examines Japan’s 1941 decision to enter the Pacific War, arguing that the Hull Note acted as the proximate trigger, provoking elite outrage and shifting preferences toward war.

Abstract Passwords remain the most widely used authentication method and play a critical role in maintaining practical security. Previous research has highlighted the influence of linguistic factors on the strength of user-created passwords, demonstrating that evaluating passwords created by users speaking languages other than English requires specific contextual knowledge. Despite this, no prior studies have specifically investigated the passwords of Japanese users. This paper presents the first study of the characteristics of Japanese user-created passwords across websites offering five types of services. Using a dataset of 48.5 million real-world leaked passwords, we conduct a comprehensive analysis of various aspects of password behavior. Our findings reveal several unique characteristics of Japanese web passwords. For instance, Japanese passwords exhibit greater dispersion compared to those of English and Chinese users, with keyboard-walk patterns being particularly prevalent among the most frequently used passwords. To address these findings, we propose a suggestion for helping users improve their password selection strategies. The experimental results demonstrate that the suggestion led to 82.15% and 93.88% of passwords being strengthened as evaluated by two effective PSMs, and reduced the cracking success rate of PCFG-guesser by up to 56.12%.

This study focuses on a system identification method for attitude control on large scale spacecraft. Large scale spacecraft generally has uncertain flexible modes that may not be modeled precisely. This paper provides a method to identify the system model for attitude control via a novel frequency-separated identification method.

Polyoxyethylene and its derivatives are highly soluble in both water and conventional organic solvents, and are widely used for many applications. Their usefulness is largely due to the ethylene glycol (EG) unit that makes up the chain. In order to understand the unique properties of the chain, many studies have been reported on its monomeric model compound, 1,2-dimethoxyethane (DME). We have attempted to study how substitution of the terminal methyl by bulky nonpolar groups affects the through-space 1,5-interaction and consequently the gauche oxygen effect of the central C-C bond. Conformational analysis of 1,2-di-tert-butoxyethane (DTBE, X-OCH2-CH2O-X with X = t-butyl) was carried out using Raman spectroscopy, with supplementary use of NMR and quantum chemical calculations. Introduction of the t-butyl groups should largely enhance the hydrophobicity of the molecular environment, yet DTBE was found to be soluble in water. While bond rotations around the terminal X-O bonds are significantly constrained, the gauche preference around the central C-C bond was found to be less affected. While electrostatic interactions play an important role in the non-hydrogen-bonding media, hydrogen-bonding comes into play in the solvents capable of forming intermolecular hydrogen-bonds. Unexpectedly, some observable amount of the through-space 1,5-t-Bu⋯O contact characteristic of the tgg' conformation was detected in DTBE in the gas phase. Unlike DME, however, such electrostatic attractions are completely suppressed in the condensed phase. These results indicate that the gauche oxygen effect of EG units is not necessarily related to the through-space 1,5-contact involving adjacent C-O bonds.

In recent years, improvised explosive devices (IEDs) have caused many casualties, especially in conflict zones. These simple powerful bombs are hard to detect due to their varied forms and hidden placements. While the number of victims has declined, around 6,000 casualties were reported in 2022. To reduce the impact on vehicles, countermeasures such as MRAP vehicles, detection sensors, and radio jamming systems are used. This study proposes an electromagnetic suspension seat system designed to protect occupants from blast injuries. The system works by detaching the seat when a shock is detected and absorbing the impact through cushioning. A scaled model was tested using a seesaw apparatus that simulated blast conditions. The results showed that the mechanism reduced the maximum acceleration transmitted to the human model below the injury threshold, although the seat separation time was slower than expected. These findings demonstrate the potential of the proposed system for occupant protection in blast scenarios.

One of the most essential applications of terahertz time-domain spectroscopy (THz-TDS) is the material parameter characterization. To assess the material parameters precisely, accurately determining the time origin of time-domain waveforms is indispensable. Here, we propose and demonstrate an analytical method for correcting the shift of the time origin due to temperature change in the fiber-laser-based THz-TDS. Based on the simple criterion that the complex refractive index spectra should be smoothest, the degree of thermal phase shift can be evaluated successfully. Using the proposed method, we can determine the dispersive complex refractive index of poly(lactic) acid thin film. Because our method has no complicated assumptions, the presented method is also applicable to the phase-resolved spectroscopy based on the time-domain measurement in other frequency regions.

This paper proposes a practical method for estimating wind in the inertial frame by estimating the parameters of an aircraft’s lateral-directional equations of motion. The north, east, and down-wind components are estimated as part of the parameters of the equations of motion, along with stability and control derivatives, using a standard estimation algorithm such as the least-squares method. The wind is assumed to be constant or linearly varying with time. The proposed method, based on the observation that the state variables regarding speed in the right-hand side of the linear equations of motion are the airspeed and that the wind is given by the coordinate transformation from the inertial frame to the body frame, is not only theoretically sound but also practically applicable. The method’s effectiveness was investigated through simulation using the flight data generated by NASA’s Generic Transport Model (GTM).

In conventional multiband base station antennas, the beam direction is the same for all shared frequency bands; however the electrical length of the antenna becomes shorter and the beam width becomes wider in the lower frequency bands. Therefore, adjacent areas experience increased interference in the low-frequency band. To solve this problem, a three-dimensional phase shifter has been proposed that can tilt the beam direction of the 1.5 GHz band from that of the 2.0 GHz band by applying a composite right-handed/left-handed (CRLH) transmission line to an an-tenna that shares the 1.5 GHz and 2.0 GHz bands. In this paper, we propose a frequency dispersive phase shifter (FDPS) that can double the phase advance compared to the conventional structure and can be constructed in a planar structure. Using an electromagnetic field simulator based on the finite element method (FEM), we clarify the structure to realize the circuit parameters. We also design a matching element that matches 50 Ω. Furthermore, we apply the designed FDPS with 5 series-connected unit cells to a 16-element array antenna consisting of 4-element subarrays, and show that the beam direction at 1.5 GHz tilt up to 8.8 degrees when the tilt angle is set to 5 degrees at 2.0 GHz. The validity of the design is verified by a prototype.