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Feathermoss is ubiquitous in the boreal forest and across various land‐cover types of the arctic and subarctic. A variety of affordable commercial sensors for soil moisture content measurement have recently become available and are in use in such regions, often in conjunction with fire‐susceptibility or ecological studies. Few come supplied with calibrations suitable or suggested for soils high in organics. Aims to test seven of these sensors for use in feathermoss, seeking calibrations between sensor output and volumetric water content.

Measurements from seven sensors installed in live, dead and burned feathermoss samples, drying in a controlled manner, were compared to moisture content measurements. Empirical calibrations of sensor output to water content were determined.

Almost all of the sensors tested were suitable for measuring the moss sample water content, and a unique calibration for each sensor for this material is presented. Differences in sensor design lead to changes in sensitivity as a function of volumetric water content, affecting the spatial averaging over the soil measurement volume.

The wide range of electromagnetic sensors available include frequency and time domain designs with variations in wave guide and sensor geometry, the location of sensor electronics and operating frequency.

This study provides information for extending the use of electromagnetic sensors to feathermoss.

A comparison of volumetric water content sensor mechanics and design is of general interest to researchers measuring soil water content. In particular, researchers working in wetlands, boreal forests and tundra regions will be able to apply these results.

This paper analyses how the history of the Mongol invasions of Japan in the 13th century was used to create a collective national memory of modern Japan and how individuals and the Japanese public promoted these memories through a campaign of constructing memorials to strengthen Japan's unified national consciousness in times of national crisis.

The main research material is derived from Japanese newspaper archives, National Diet library database as well as Japanese and English secondary literature.

This paper argues that three Japanese concepts, such as kokunan (national crisis), kokui (national prestige or pride) and gokoku (protecting the country), were essential for the creation of collective Japanese memory and identity.

The paper outlines the narrative formed around the history of the Mongol invasions of Japan to create a unified national identity through a collective historical memory in times of Japanese “national crisis” felt in its external relations.

The purpose of this paper is to propose methods for fast incremental indexing with effective and efficient query processing in XML element retrieval. The effectiveness of a search system becomes lower if document updates are not handled when these occur frequently on the Web. The search accuracy is also reduced if drastic changes in document statistics are not managed. However, existing studies of XML element retrieval do not consider document updates, although these studies have attained both effectiveness and efficiency in query processing. Thus, the authors add a function for handling document updates to the existing techniques for XML element retrieval.

Though it will be important to enable fast updates of indices, preliminary experiments have shown that a simple incremental update approach has two problems: some kinds of statistics are inaccurate, and it takes a long time to update indices. Therefore, two methods are proposed: one to approximate term weights accurately with a small number of documents, even for dynamically changing statistics; and the other to eliminate unnecessary update targets.

Experimental results show that this proposed system can update indices up to 32 per cent faster than the simple incremental updates while the search accuracy improved by 4 per cent compared with the simple approach. The proposed methods can also be fast and accurate in query processing, even if document statistics change drastically.

The paper shows that there could be a more practical XML element search engine, which can access the latest XML documents accurately and efficiently.

Nowadays there are a large number of XML documents on the web. This means that information retrieval techniques for searching XML documents are very important and necessary for internet users. Moreover, it is often said that users of search engines want to browse only relevant content in each document. Therefore, an effective XML element search aims to produce only the relevant elements or portions of an XML document. Based on the demand by users, the purpose of this paper is to propose and evaluate a method for obtaining more accurate search results in XML search.

The existing approaches generate a ranked list in descending order of each XML element's relevance to a search query; however, these approaches often extract irrelevant XML elements and overlook more relevant elements. To address these problems, the authors' approach extracts the relevant XML elements by considering the size of the elements and the relationships between the elements. Next, the authors score the XML elements to generate a refined ranked list. For scoring, the authors rank high the XML elements that are the most relevant to the user's information needs. In particular, each XML element is scored using the statistics of its descendant and ancestor XML elements.

The experimental evaluations show that the proposed method outperforms BM25E, a conventional approach, which neither reconstructs XML elements nor uses descendant and ancestor statistics. As a result, the authors found that the accuracy of an XML element search can be improved by reconstructing the XML elements and emphasizing the informative ones by applying the statistics of the descendant XML elements.

This work focused on the effectiveness of XML element search and the authors did not consider the search efficiency in this paper. One of the authors' next challenges is to reduce search time.

The paper proposes a method for improving the effectiveness of XML element search.