Jove
Visualize
お問い合わせ
JoVE
x logofacebook logolinkedin logoyoutube logo
JoVEについて
概要リーダーシップブログJoVEヘルプセンター
著者向け
出版プロセス編集委員会範囲と方針査読よくある質問投稿
図書館員向け
推薦の声購読アクセスリソース図書館諮問委員会よくある質問
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experimentsアーカイブ
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教員リソースセンター教員サイト
利用規約
プライバシーポリシー
ポリシー

関連する概念動画

Entropy02:39

Entropy

35.0K
Salt particles that have dissolved in water never spontaneously come back together in solution to reform solid particles. Moreover, a gas that has expanded in a vacuum remains dispersed and never spontaneously reassembles. The unidirectional nature of these phenomena is the result of a thermodynamic state function called entropy (S). Entropy is the measure of the extent to which the energy is dispersed throughout a system, or in other words, it is proportional to the degree of disorder of a...
35.0K
Entropy01:18

Entropy

3.5K
The first law of thermodynamics is quantitatively formulated via an equation relating the internal energy of a system, the heat exchanged by it, and the work done on it. A quantitative formulation of the second law of thermodynamics leads to defining a state function, the entropy.
When an ideal gas expands isothermally, the disorder in the gas increases. From the molecular perspective, the gas molecules have more volume to move around in.
Consider an infinitesimal step in the expansion, which...
3.5K
Standard Entropy Change for a Reaction03:00

Standard Entropy Change for a Reaction

24.0K
Entropy is a state function, so the standard entropy change for a chemical reaction (ΔS°rxn) can be calculated from the difference in standard entropy between the products and the reactants.
24.0K
Entropy and Solvation02:05

Entropy and Solvation

8.3K
The process of surrounding a solute with solvent is called solvation. It involves evenly distributing the solute within the solvent. The rule of thumb for determining a solvent for a given compound is that like dissolves like. A good solvent has molecular characteristics similar to those of the compound to be dissolved. For example, polar solutions dissolve polar solutes, and apolar solvents dissolve apolar solutes. A polar solvent is a solvent that has a high dielectric constant (ϵ...
8.3K
Entropy within the Cell01:22

Entropy within the Cell

12.7K
A living cell's primary tasks of obtaining, transforming, and using energy to do work may seem simple. However, the second law of thermodynamics explains why these tasks are harder than they appear. None of the energy transfers in the universe are completely efficient. In every energy transfer, some amount of energy is lost in a form that is unusable. In most cases, this form is heat energy. Thermodynamically, heat energy is defined as the energy transferred from one system to another that...
12.7K
Entropy and the Second Law of Thermodynamics01:20

Entropy and the Second Law of Thermodynamics

4.8K
The second law of thermodynamics can be stated quantitatively using the concept of entropy. Entropy is the measure of disorder of the system.
The relation  between entropy and disorder can be illustrated with the example of the phase change of ice to water. In ice, the molecules are located at specific sites giving a solid state, whereas, in a liquid form, these molecules are much freer to move. The molecular arrangement has therefore become more randomized. Although the change in average...
4.8K

こちらも読む

関連記事

共著者、ジャーナル、引用グラフによってこの研究に関連する記事。

並び替え
Same author

Underwater Acoustic Target Recognition Based on Attention Residual Network.

Entropy (Basel, Switzerland)·2022
Same author

DOT1L regulates dystrophin expression and is critical for cardiac function.

Genes & development·2011
Same author

The ribosomal intergenic spacer (IGS) region in Schistosoma japonicum: structure and comparisons with related species.

Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases·2011
Same author

Effects of intravesical liposome-mediated human beta-defensin-2 gene transfection in a mouse urinary tract infection model.

Microbiology and immunology·2011
Same author

A polyacrylamide microbead-integrated chip for the large-scale manufacture of ready-to-use esiRNA.

Lab on a chip·2011
Same author

Investigation on wide-band scattering of a 2-D target above 1-D randomly rough surface by FDTD method.

Optics express·2011

関連する実験動画

Updated: Jan 22, 2026

Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy
11:15

Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy

Published on: June 27, 2013

34.4K

スペクトルエントロピー駆動型マルチパス分離に基づく水中時間遅延推定法

Xuerong Cui1, Lurui Chao1, Juan Li2

  • 1College of Oceanography and Space Informatics, China University of Petroleum (East China), Qingdao, 266000, China.

The Journal of the Acoustical Society of America
|January 21, 2026
PubMed
まとめ

本研究では、水中時間遅延推定のための新しいスペクトルエントロピー駆動型手法を導入します。これにより、マルチパス信号を効果的に分離し、ノイズの多い複雑な音響環境での測位精度が向上します。

キーワード:
水中音響チャネルマルチパス時間遅延推定スペクトルエントロピー測位精度ノイズ除去

さらに関連する動画

Optimization of Processing of Tiebangchui with Highland Barley Wine Based on the Box-Behnken Design Combined with the Entropy Method
09:12

Optimization of Processing of Tiebangchui with Highland Barley Wine Based on the Box-Behnken Design Combined with the Entropy Method

Published on: May 19, 2023

1.2K
Development of New Methods for Quantifying Fish Density Using Underwater Stereo-video Tools
09:32

Development of New Methods for Quantifying Fish Density Using Underwater Stereo-video Tools

Published on: November 20, 2017

9.7K

関連する実験動画

Last Updated: Jan 22, 2026

Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy
11:15

Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy

Published on: June 27, 2013

34.4K
Optimization of Processing of Tiebangchui with Highland Barley Wine Based on the Box-Behnken Design Combined with the Entropy Method
09:12

Optimization of Processing of Tiebangchui with Highland Barley Wine Based on the Box-Behnken Design Combined with the Entropy Method

Published on: May 19, 2023

1.2K
Development of New Methods for Quantifying Fish Density Using Underwater Stereo-video Tools
09:32

Development of New Methods for Quantifying Fish Density Using Underwater Stereo-video Tools

Published on: November 20, 2017

9.7K

科学分野:

  • 音響学
  • 信号処理
  • 海洋学

背景:

  • 水中音響チャネルはマルチパス効果に悩まされ、信号エイリアシングを引き起こします。
  • 非定常な海洋ノイズは、既存の時間遅延推定アルゴリズムをさらに劣化させます。
  • 高精度な水中測位は、正確な時間遅延推定に大きく依存しています。

研究 の 目的:

  • 複雑な水中環境のための堅牢な時間遅延推定手法を開発すること。
  • 信号エイリアシングとノイズ干渉の問題に対処すること。
  • 水中測位の精度を向上させること。

主な方法:

  • スペクトルエントロピー駆動型マルチパス分離技術を提案しました。
  • モード選択のためにスペクトルエントロピー駆動型帯域幅オーバーラップ基準を利用しました。
  • エネルギー勾配と情報エントロピーを組み込んだ時間領域エネルギー検出メカニズムを実装しました。

主要な成果:

  • 効果的なマルチパスモードの動的選択とノイズ優勢モードの破棄を達成しました。
  • 時間周波数エイリアシング信号の分離に成功しました。
  • シミュレーションにおいて、マルチパス分離精度の顕著な向上（52.1%-61.4%）と時間遅延RMSEの削減（36.6%-47.2%）を示しました。

結論:

  • 提案手法は、固定パラメータモーダル分解の限界を克服します。
  • 低信号対雑音比条件下でも高精度な時間遅延推定を可能にします。
  • 困難な水中音響環境におけるマルチパス測位のための理論的進歩を提供します。