Ehime Prefecture
Evaluate What You Can't Evaluate: Unassessable Quality for Generated Response
Liu, Yongkang, Feng, Shi, Wang, Daling, Zhang, Yifei, Schütze, Hinrich
LLMs (large language models) such as ChatGPT have shown remarkable language understanding and generation capabilities. Although reference-free evaluators based on LLMs show better human alignment than traditional reference-based evaluators, there are many challenges in using reference-free evaluators based on LLMs. Reference-free evaluators are more suitable for open-ended examples with different semantics responses. But not all examples are open-ended. For closed-ended examples with unique correct semantic response, reference-free evaluators will still consider it high quality when giving a response that is inconsistent with the facts and the semantic of reference. In order to comprehensively evaluate the reliability of evaluators based on LLMs, we construct two adversarial meta-evaluation dialogue generation datasets KdConv-ADV and DSTC7-ADV based on KdConv and DSTC7-AVSD, respectively. Compared to previous meta-evaluation benchmarks, KdConv-ADV and DSTC7-ADV are much more challenging since they requires evaluators to be able to reasonably evaluate closed-ended examples with the help of external knowledge or even its own knowledge. Empirical results show that the ability of LLMs to identify unreasonable responses is insufficient. There are risks in using eference-free evaluators based on LLMs to evaluate the quality of dialogue responses.
First counterterror drill for drone attack held at nuclear plant in Ehime
Some 60 people from the police and Japan Coast Guard participated in the exercise at the Ikata nuclear power plant, which simulated a drone launched from a boat planting a makeshift explosive device on the premises of reactor 3. Officials of Shikoku Electric Power Co., which runs the plant, and members of the bomb disposal unit in the Ehime Prefectural Police also took part. "We took into account the serious situation regarding terrorism in conducting this drill, and I think it is important to prepare for the unpredictable," said Hideto Murase, the local security chief of the Ehime Prefectural Police. Reactor 3 was restarted last August after clearing safety requirements introduced after the March 2011 Fukushima nuclear crisis. The reactor runs on plutonium-uranium mixed oxide fuel, or MOX, which contains plutonium extracted by reprocessing spent fuel. Shikoku Electric plans to finish building by March 2020 a facility that is capable of withstanding major terror attacks, such as those involving intentional aircraft crashes, and preventing the release of radioactive materials.
SAR Image Despeckling Algorithms using Stochastic Distances and Nonlocal Means
Torres, Leonardo, Frery, Alejandro C.
This paper presents two approaches for filter design based on stochastic distances for intensity speckle reduction. A window is defined around each pixel, overlapping samples are compared and only those which pass a goodness-of-fit test are used to compute the filtered value. The tests stem from stochastic divergences within the Information Theory framework. The technique is applied to intensity Synthetic Aperture Radar (SAR) data with homogeneous regions using the Gamma model. The first approach uses a Nagao-Matsuyama-type procedure for setting the overlapping samples, and the second uses the nonlocal method. The proposals are compared with the Improved Sigma filter and with anisotropic diffusion for speckled data (SRAD) using a protocol based on Monte Carlo simulation. Among the criteria used to quantify the quality of filters, we employ the equivalent number of looks, and line and edge preservation. Moreover, we also assessed the filters by the Universal Image Quality Index and by the Pearson correlation between edges. Applications to real images are also discussed. The proposed methods show good results.
Polarimetric SAR Image Smoothing with Stochastic Distances
Torres, Leonardo, Medeiros, Antonio C., Frery, Alejandro C.
Polarimetric Synthetic Aperture Radar (PolSAR) images are establishing as an important source of information in remote sensing applications. The most complete format this type of imaging produces consists of complex-valued Hermitian matrices in every image coordinate and, as such, their visualization is challenging. They also suffer from speckle noise which reduces the signal-to-noise ratio. Smoothing techniques have been proposed in the literature aiming at preserving different features and, analogously, projections from the cone of Hermitian positive matrices to different color representation spaces are used for enhancing certain characteristics. In this work we propose the use of stochastic distances between models that describe this type of data in a Nagao-Matsuyama-type of smoothing technique. The resulting images are shown to present good visualization properties (noise reduction with preservation of fine details) in all the considered visualization spaces.