Recent advancements in machine learning-based car-following models have shown promise in leveraging vehicle trajectory data to accurately reproduce real-world driving behaviour in simulations. However, existing data-driven car-following models only explicitly consider individual vehicle trajectories for model training, overlooking broader traffic phenomena. This limitation hinders their ability to accurately capture the oscillation dynamics of vehicle platoons, which are critical for simulating and evaluating mesoscopic and macroscopic traffic phenomena such as congestion propagation, stop-and-go, string stability and hysteresis. To fill this gap, our study introduces a hybrid physical model-driven and data-driven framework, Multiscale Car-Following (MultiscaleCF), aimed at explicitly capturing mesoscopic oscillation dynamics within data-driven car-following models. MultiscaleCF offers two methodological advancements in the development of machine learning-based car-following models: the recursive simulation of a platoon of vehicles to reduce compound error and mesoscopic feature engineering using domain-specific attributes. Evaluated using the OpenACC database, the MultiscaleCF framework exhibited a simultaneous improvement in both microscopic and mesoscopic traffic simulation patterns. It outperforms the baseline model in microscopic trajectory prediction accuracy by up to 21%. For oscillation dynamics, it outperforms the baseline model by 42%, 32%, 29% and 42% in duration, amplitude, intensity, and hysteresis magnitude, respectively.

This article demonstrates that there is a fundamental relationship between temporal logic and languages that involve multiple stages, such as those used to analyze binding times in the context of partial evaluation. This relationship is based on an extension of the Curry-Howard isomorphism, which identifies proofs with programs, and propositions with types. Our extension involves the “next time” (○) operator from linear-time temporal logic and yields a λ-calculus λ° with types of the form ○ A for expressions in the subsequent stage, with appropriate introduction and elimination forms. We demonstrate that λ° is equivalent to the core of a previously studied multilevel binding-time analysis. This is similar to work by Davies and Pfenning on staged computation based on the necessity (□) operator of modal logic, but □ only allows closed code, and naturally supports a code evaluation construct, whereas ○ captures open code, thus is more flexible, but is incompatible with such a construct. Instead, code evaluation is an external global operation that is validated by the proof theory regarding closed proofs of ○ formulas. We demonstrate the relevance of λ° to staged computation directly by showing that that normalization can be done in an order strictly following the times of the logic. We also extend λ° to small functional language and show that it would serve as a suitable basis for directly programming with multiple stages by presenting some example programs.

Ear detection from a profile face image is an important step in many applications including biometric recognition. But accurate and rapid detection of the ear for real-time applications is a challenging task, particularly in the presence of occlusions. In this work, a cascaded AdaBoost based ear detection approach is proposed. In an experiment with a test set of 203 profile face images, all the ears were accurately detected by the proposed detector with a very low (5 × 10-6) false positive rate. It is also very fast and relatively robust to the presence of occlusions and degradation of the ear images (e.g. motion blur). The detection process is fully automatic and does not require any manual intervention.

We show that a type system based on the intuitionistic modal logic S4 provides an expressive framework for specifying and analyzing computation stages in the context of typed λ-calculi and functional languages. We directly demonstrate the sense in which our λ e →□ -calculus captures staging, and also give a conservative embeddng of Nielson and Nielson's two-level functional language in our functional language Mini-ML □ , thus proving that binding-time correctness is equivalent to modal correctness on this fragment. In addition, Mini-ML □ can also express immediate evaluation and sharing of code across multiple stages, thus supporting run-time code generation as well as partial evaluation.

We reconsider the foundations of modal logic, following Martin-Löf's methodology of distinguishing judgments from propositions. We give constructive meaning explanations for necessity and possibility, which yields a simple and uniform system of natural deduction for intuitionistic modal logic that does not exhibit anomalies found in other proposals. We also give a new presentation of lax logic and find that the lax modality is already expressible using possibility and necessity. Through a computational interpretation of proofs in modal logic we further obtain a new formulation of Moggi's monadic metalanguage.

We show that standard formulations of intersection type systems are unsound in the presence of computational effects, and propose a solution similar to the value restriction for polymorphism adopted in the revised definition of Standard ML. It differs in that it is not tied to let-expressions and requires an additional weakening of the usual subtyping rules. We also present a bi-directional type-checking algorithm for the resulting language that does not require an excessive amount of type annotations and illustrate it through some examples. We further show that the type assignment system can be extended to incorporate parametric polymorphism. Taken together, we see our system and associated type-checking algorithm as a significant step towards the introduction of intersection types into realistic programming languages. The added expressive power would allow many more properties of programs to be stated by the programmer and statically verified by a compiler.

The World Wide Web is rich in content and services, but access to these resources must be obtained mostly through manual browsers. We would like to be able to write programs that reproduce human browsing behavior, including reactions to slow transmission-rates and failures on many simultaneous links. We thus introduce a concurrent model that directly incorporates the notions of failure and rate of communication, and then describe programming constructs based on this model.

The Curry-Howard isomorphism identifies proofs with typed /spl lambda/-calculus terms, and correspondingly identifies propositions with types. We show how this isomorphism can be extended to relate constructive temporal logic with binding-time analysis. In particular we show how to extend the Curry-Howard isomorphism to include the O ("next") operator from linear-time temporal logic. This yields the simply typed /spl lambda//sup O/-calculus which we prove to be equivalent to a multi-level binding-time analysis like those used in partial evaluation for functional programming languages. Further, we prove that normalization in /spl lambda//sup O/ can be done in an order corresponding to the times in the logic, which explains why /spl lambda//sup O/ is relevant to partial evaluation. We then extend /spl lambda//sup O/ to a small functional language, Mini-ML/sup O/, and give an operational semantics for it. Finally, we prove that this operational semantics correctly reflects the binding-times in the language, a theorem which is the functional programming analog of time-ordered normalization.

We show that a type system based on the intuitionistic modal logic S4 provides an expressive framework for specifying and analyzing computation stages in the context of functional languages. Our main technical result is a conservative embedding of Nielson & Nielson's two-level functional language in our language Mini-ML, thus proving that binding-time correctness is equivalent to modal correctness on this fragment. In addition Mini-ML can also express immediate evaluation and sharing of code across multiple stages, thus supporting run-time code generation as well as partial evaluation.