The three-body recombination of a condensed Bose gas near a Feshbach resonance

In this paper, we study the three-body recombination rate of a homogeneous dilute Bose gas with a Feshbach resonance at zero temperature. The ground state and excitations of this system are obtained. The three-body recombination in the ground state is due to the break-up of an atom pair in the quantum depletion and the formation of a molecule by an atom from the broken pair and an atom from the condensate. The rate of this process is in good agreement with the experiment on $^{23}$Na in a wide range of magnetic fields.Comment: 10 pages, 2 figures, to be published in Phys. Rev.

信号の多重化方式変換における複数の光信号処理の一括動作

近年、インターネットやスマートフォンなどの普及により、大容量かつ高速なネットワークの実現が求められている。そのため、光通信における信号の多重化技術の研究が進められており、特に、波長分割多重(WDM: Wavelength Division Multiplexing)及び光時分割多重(OTDM: Optical Time Division Multiplexing)が積極的に利用されている。波長分割多重は広い波長領域にわたる光ファイバの低損失性を有効に利用する特徴がある一方、光時分割多重は伝送速度を高速化する利点があるため、これらの多重化技術を組み合わせることにより、高速で大容量なネットワークが実現されることが期待されている。多様な多重化技術をそれぞれ採用するネットワーク同士を接続する際、WDM/OTDM間の信号フォーマット変換が重要な役割を果たしている。しかし、WDM/OTDM変換及び信号フォーマット変換を単に組み合わせると系が複雑になる。そこで、本報告では、簡単な構成を目的とした信号の多重化方式変換における複数の光信号処理の一括動作をNRZ-OOK(Nonreturn to Zero-On Off Keying)信号に応用し、検証した。　まず、2×10Gb/s NRZ-OOK信号に対して、波形変換及びWDM-to-OTDM変換の一括動作を検証するあたり、クロック光のパルス圧縮なし及びクロック光のパルス圧縮あり、の二つの場合について検証を行った。その結果として、パルス圧縮なしの場合では波形変換及び多重化変換の一括動作で、単チャネル分離後、符号誤り率特性におけるエラーフリーを達成できたのに対して、パルス圧縮ありの場合では、波形変換及び多重化変換の一括動作は成功したが、変換後のOTDM信号波形の劣化により、多重分離を行うことができなかった。　さらに、パルス圧縮なしの場合と同じ構成で、入力信号の波長を変えることにより波形変換及びWDM-to-Multi-OTDM変換の一括動作を提案し、検証を行った。その結果、2×10Gb/sWDM(NRZ-OOK)-to-2×20Gb/sOTDM(RZ-OOK)変換に成功し、OTDM信号の波形劣化は観察された。したがって、一括動作後に有効なOTDM信号が得られている。電気通信大学201

The Impact of Byline Order of Corresponding Author - A Preliminary Study

Corresponding author (C-Au) holds an important position in byline order. Some papers have analyzed the contribution of C-Au, but they do not consider the variation in different byline order. Furthermore, some studies use ques-tionnaire and found that people perception on other authors’ contribution would be influence by the byline order of C-Au, but the real situation remains unclear. Thus, this poster aims to analyze two questions: (1) What kind of byline order do C-Au have and are their contribution influenced by their by-line order? (2) Are other authors contributions influenced by the byline order of C-Au? Three main findings emerge: firstly, the last author are not always to be C-Au; following with the decline of byline order of C-Au, the contribution of C-Au deceases; finally, as the byline order of C-Au changes, other authors’ contribution change significantly. For instance, second author has the lowest contribution when the last author is C-Au

Does Attention Mechanism Possess the Feature of Human Reading? A Perspective of Sentiment Classification Task

[Purpose] To understand the meaning of a sentence, humans can focus on important words in the sentence, which reflects our eyes staying on each word in different gaze time or times. Thus, some studies utilize eye-tracking values to optimize the attention mechanism in deep learning models. But these studies lack to explain the rationality of this approach. Whether the attention mechanism possesses this feature of human reading needs to be explored. [Design/methodology/approach] We conducted experiments on a sentiment classification task. Firstly, we obtained eye-tracking values from two open-source eye-tracking corpora to describe the feature of human reading. Then, the machine attention values of each sentence were learned from a sentiment classification model. Finally, a comparison was conducted to analyze machine attention values and eye-tracking values. [Findings] Through experiments, we found the attention mechanism can focus on important words, such as adjectives, adverbs, and sentiment words, which are valuable for judging the sentiment of sentences on the sentiment classification task. It possesses the feature of human reading, focusing on important words in sentences when reading. Due to the insufficient learning of the attention mechanism, some words are wrongly focused. The eye-tracking values can help the attention mechanism correct this error and improve the model performance. [Originality/value] Our research not only provides a reasonable explanation for the study of using eye-tracking values to optimize the attention mechanism, but also provides new inspiration for the interpretability of attention mechanism

Aluminum Mineral Processing and Metallurgy: Iron-Rich Bauxite and Bayer Red Muds

Bauxite is the main source for alumina production. With the rapid development of iron and steel industry and aluminum industry, high-quality iron ore and bauxite resources become increasingly tense. However, a lot of iron-rich bauxite and Bayer red mud resources have not been timely and effectively recycled, resulting in serious problems of environmental pollution and wastage of resources. The comprehensive utilization of iron-rich bauxite and red mud is still a worldwide problem. The industrial stockpiling is not a fundamental way to solve the problems of iron-rich bauxite and red mud. As to the recovery of valuable metals from iron-rich bauxite and red mud, there are a lot of technical and cost problems, which are serious impediments to industrial development. Applying red mud as construction materials like cement, soil ameliorant applications face the problem of Na, Cr, As leaching into the environment. However, the high-temperature reduction, smelting and alkaline leaching process is a feasible method to recover iron and alumina from iron-rich bauxite and red mud. This chapter intends to provide the reader an overview on comprehensive utilization technology of the low-grade iron-rich bauxite and Bayer red mud sources