Kazuyuki YamamotoAssociate Professor
■Researcher basic information
Research Areas
Educational Background
Career
■Research activity information
Paper
- Categorization of ICT Inquiry Data using Mail Subjects
Taisuke Kawamata; Kazuyuki Yamamoto; Yasuhiro Ohtaki, 情報系センターにおける業務の一つである問合わせ対応の効率化を目的に，問合わせデータを機械的にカテゴライズする方法を検討した．問合わせはメールで行われることが多いが，メールの本文には問合わせと無関係なノイズが多く含まれ，それらのノイズを前処理で削除するための工程が，自動的なカテゴライズを困難なものにしている．そこで本研究では，メールの件名が本文の要約であり，また短文であることからノイズが少ないという点に着目し，件名の活用方法について検討を行う．短文に含まれる単語情報を効果的に活用するため，文書の文脈を考慮することが可能な深層言語モデルBERTを用いて特徴抽出を行った．実際の問い合わせデータを対象に，抽出した特徴をクラスタリングし，人間のカテゴライズと比較した．その結果，件名を用いた分類は本文を用いた分類よりも意味としてまとまったクラスタを生成することが明らかになった．これにより，件名を活用することで，メール分析における前処理の課題を解決できる可能性が示唆された．, Academic eXchange for Information Environment and Strategy
Journal for Academic Computing and Networking, Nov. 2024, [Reviewed] - Constructing a Client Certificate Distribution System
Yasuhiro Ohtaki; Kazuyuki Yamamoto, Springer
Lecture Notes in Networks and Systems. NBiS 2022, Sep. 2022, [Reviewed] - Constructing a Network with Unified Cybersecurity Measure for Primary and Secondary School Students
Kazuyuki Yamamoto; Yasuhiro Ohtaki; Hiroshi Noguchi; Tadafumi Nishihara; Hiromasa Habuchi and Hideyuki Tonooka, Lead, 学術情報処理研究編集委員会
Journal for Academic Computing and Networking, Nov. 2021, [Reviewed] - Estimating User's Movement Path using Wi-Fi Authentication Log
Jun Yamano; Yasuhiro Ohtaki; Kazuyuki Yamamoto, Springer
Lecture Notes in Networks and Systems. NBiS 2021, Sep. 2021, [Reviewed] - Categorization of ICT Inquiry Data using Distributed Representation
Kazuyuki Yamamoto; Yasuhiro Ohtaki; Shinya Sato; Toshiyuki Shimada; Hiroshi Noguchi; Hiromasa Habuchi; Hideyuki Tonooka, Lead, 学術情報処理研究編集委員会
Journal for Academic Computing and Networking, 01 Dec. 2020, [Reviewed] - How did Ibaraki University Cope with Distance Learning and Telecommuting?
Yasuhiro Ohtaki; Toshiyuki Shimada; Kazuyuki Yamamoto; Hiroshi Noguchi; Shinya Sato; Hideyuki Tonooka; Habuchi Hiromasa, 学術情報処理研究編集委員会
Journal for Academic Computing and Networking, 01 Dec. 2020, [Reviewed] - Enabling Nessesity Multi-Factor Authentication for levels and Expanding the scope of Authentication Federation
Hiroshi Noguchi; Yasuhiro Ohtaki; Kazuyuki Yamamoto; Tadafumi Nishihara; Hideyuki Tonooka, 学術情報処理研究編集委員会
Journal for Academic Computing and Networking, 01 Dec. 2020, [Reviewed] - Changes in students’ behavior due to changes of the printing environment
Yasuhiro Ohtaki; Hiroshi Noguchi; Kazuyuki Yamamoto; Hideyuki Tonooka and Masaru Kamada, 学術情報処理研究編集委員会
学術情報処理研究, 17 Sep. 2019, [Reviewed] - Development and Verification of CSIRT Information Sharing System for Cyber Security Incident Response in Ibaraki University
Kazuyuki Yamamoto; Yasuhiro Ohtaki; Hiroshi Noguchi; Hiromasa Habuchi and Hideyuki Tonooka, Lead, 学術情報処理研究編集委員会
学術情報処理研究, 17 Sep. 2019, [Reviewed] - Identification of Unutilized IP Address and Inventory by Using Host Registration System
S. Aoyama; K. Yamamoto; K. Miyakita; K. Mikawa, Corresponding, 学術情報処理研究編集委員会
学術情報処理研究, 10 Sep. 2018, [Reviewed] - Modification of IP Address Management Database with Network Access Authentication
K. Miyakita; K. Yamamoto; S. Aoyama; K. Mikawa
インターネットと運用技術シンポジウム2016論文集, 01 Dec. 2016, [Reviewed] - Operation and Extension of IP Address Management Database with Network Access Authentication
Kazuyuki Miyakita; Kazuyuki Yamamoto; Shigeyoshi Aoyama; Kenji Mikawa
情報処理学会研究報告インターネットと運用技術, 19 May 2016 - Guidance of information security measure necessary for student teachers in Niigata University
佐藤亮一,佐藤雄二,平賀保博,早川潤,畠山森魚,青山茂義,山本一幸,岡野勉,下保敏和,鈴木賢治, In this paper, we introduce our efforts to improve educational effects on" information security measure" for all the students who want to be teachers in Niigata University, in the pre-training guidance hosted by Faculty of Education, Niigata University, in collaboration with Center for Academic Information Service, Niigata University. Our security guidance simply comprises the following four items as 1) Understanding and dissemination of" information security policies" not only for university but also for practice schools (for the boards of education where the practice schools belong to), 2) Requirement of filling out and submitting "security check sheet" for the students who want to bring their computers and the related ICT devices to the schools, 3) Human support for the students who do not have enough skill to carry out the security measure procedure to their computers by themselves, and 4) Providing secure environment for them to safely do the security measure to their computers without risk of computer virus infection., 新潟大学教育学部
新潟大学教育学部研究紀要 自然科学編, Mar. 2015 - Network design and operation for Niigata University wireless LAN system using dynamic VLAN assignments
K. Yamamoto; S. Aoyama; K. Mikawa, Lead, 学術情報処理研究編集委員会
Journal for Academic Computing ,and Networking, 25 Sep. 2014, [Reviewed] - Particle Capture Reaction using Extended Core Plus Valence Nucleon Model
K. Yamamoto; H. Masui; M. Ohta; K. Kato, We investigate the O-17(n, gamma)O-18 capture reaction cross section at the astrophysical energy using a microscopic O-16+n+n, model. The data of this reaction cross section for the s-process nucleosynthesis becomes important. The O-17(n, gamma)O-18 reaction cross section is not measured by the experiment, because the natural abundance of O-17 is the 0.038%. We consider that it is necessary to estimate the O-17(n, gamma)O-18 reaction cross section by a theoretical approach. In this paper, we apply the available wave function obtained by the microscopic O-16+n+n model to the estimation of the O-17(n, gamma)O-18 reaction cross section., KOREAN PHYSICAL SOC
JOURNAL OF THE KOREAN PHYSICAL SOCIETY, Aug. 2011, [Reviewed] - EFFECT OF O-16 CORE EXCITATION FOR PARTICLE CAPTURE REACTIONS AT ASTROPHYSICAL ENERGY
Kazuyuki Yamamoto; Hiroshi Masui; Masahisa Ohta; Kiyoshi Kato, In order to investigate the particle capture reactions at the astrophysical energy, we consider that the structure of the negative-parity states near the threshold energy becomes important. To study the structure, it is necessary to extend the model space take into account the effect of the core excitation. In this paper, we discuss the effect of the core excitation for the reaction cross sections at the astrophysical energy., WORLD SCIENTIFIC PUBL CO PTE LTD
MODERN PHYSICS LETTERS A, Jul. 2010 - Study of 16O(n,g)17O reaction with core excitation
K. Yamamoto; H. Masui; M. Ohta; K. Kato, Lead, We extend the model space for a theoretical evaluation of cross sections and reaction rates in astrophysical energies. In order to reproduce the experimental data of the O-16(n, gamma)O-17 reaction near the threshold energy through the El transition, the investigation of the transition from an s-wave scattering state to the negative:parity bound states of O-17 becomes important. To obtain the negative-parity bound states of the O-17, it is necessary to take into account the excitation of the O-16 core. In this paper, we estimate the mixing of the one particle - one hole excitation for the low-lying states using the norm kernel calculation and derive the intrinsic densities of the closed shell and the one particle - one hole configuration of O-16., AMER INST PHYSICS
AIP Conference Proceedings, 01 Jun. 2010 - Effect of Uncertainties in Nuclear Reaction Rate on Nucleosynthesis Paths
Kazuyuki Yamamoto; Kiyoshi Kato; Takahiro Wada; Masahisa Ohta, We propose a Monte Carlo analysis that provides us with a useful diagnostic method to identify the nucleosynthesis paths giving helpful information to understand the nuclear burning mechanism in stellar evolution, connecting with network calculations. Applying the Monte Carlo analysis to the nucleosynthesis in the He shell flash model, we show that a. considerable change in synthesis paths occurs from (16)O to Ne isotopes depending on the reaction rate of (17)O(n, gamma)(18)O., PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE
PROGRESS OF THEORETICAL PHYSICS, Jun. 2010, [Reviewed] - Radiative Capture Cross Section for O-16(n, gamma)O-17 and O-16(p, gamma)F-17 below Astrophysical Energies
Kazuyuki Yamamoto; Hiroshi Masui; Kiyoshi Kato; Takahiro Wada; Masahisa Ohta, In this paper we aim to construct a reliable theoretical framework to analyze nuclear reaction cross sections concerning the nucleosyntheses of light nuclei. To explain the reaction cross sections of O-16(n, gamma)O-17 and O-16(p, gamma)F-17, we propose a theoretical procedure combining an O-16+N model and the complex scaling method with the Lippmann-Schwinger solution for the complex-scaled Green's operator. We demonstrate that this procedure is a powerful tool in the analysis of the reactions observed in the lower-energy region including astrophysical energies., PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE
PROGRESS OF THEORETICAL PHYSICS, Feb. 2009, [Reviewed] - Neutron capture reaction in oxygen nuclei near threshold energy regions
K. Yamamoto; H. Masui; K. Kato; T. Wada and M. Ohta, Lead, For the key reactions O-16(n, gamma)O-17 and O-17(n, gamma)O-18 on nucleosyntheses in stellar interior, the theoretical estimate for the cross section and reaction rate have been made. The careful description of the nuclear structure is important in very low energy regions. The Cluster Orbital Shell Model is adopted for reproducing the structure of the nuclei. Our results for the cross section of the O-16(n, gamma)O-17 reaction are consistent with that of the microscopic two cluster model. The straightforward application becames possible to the case of the O-17(n, gamma)O-18 reaction with a substantial reliance., AMER INST PHYSICS
AIP Conference Proceedings, 21 May 2008 - Fission modes of neutron-rich nuclei in the r-process nucleosynthesis
S. Tatsuda; K. Yamamoto; T. Asano; M. Ohta; T. Wada; S. Chiba; H. Koura; T. Maruyama; T. Tachibana; T. Kajino; K. Sumiyoshi and K. Otsuki, The fission fragments mass distribution (FFMD) which is the important nuclear information in the study of the r-process nucleosynthesis is estimated for the neutron-rich nuclei (Z>85) according to the theoretical investigation of the potential energy surface. The details for determining FFMD are discussed. In this paper, the network calculation on the r-process nucleosynthesis is also performed including the data of FFMD. The comparison of the results of the network calculation, with and without the fission processes, is shown., AMER INST PHYSICS
AIP Conference Proceedings, 21 May 2008 - Systematic study for the mass distribution of fission fragments in the neutron rich region
M. Ohta; S. Tatsuda; T. Hashizume; K. Yamamoto; T. Wada; K. Sumiyoshi; K. Otsuki; T. Kajino; H. Koura; S. Chiba; T. Tachibana, The systematic data on the fission fragment mass distribution for nuclei ranging from Z = 88 to 120 relevant to the r-process nucleosynthesis is constructed in a semi-empirical way. The mass distribution is estimated from the potential energy surface by means of the liquid drop model with the shell energy correction and also by referring the results in the dynamical calculation of fission paths by the Langevin equation in the three-dimensional deformation space. The results are compared with the mass asymmetric values at the saddle point driven by the extended Thomas-Fermi Struchinsky integral (ETFSI) model. In the lighter nuclei Z < 100, our results are consistent with the values of ETFSI, on the other hand in the heavier nuclei our estimation gives a larger mass asymmetry and approaches to zero due to the decrease of shell effect beyond Z > 120., E D P SCIENCES
INTERNATIONAL CONFERENCE ON NUCLEAR DATA FOR SCIENCE AND TECHNOLOGY, VOL 1, PROCEEDINGS, 2008 - 恒星における元素合成と関係する天体核反応データの問題点
山本 一幸; 和田 隆宏; 太田 雅久; 西村 高徳; 藤本 正行; 加藤 幾芳; 合川 正幸; 須田 拓馬, Lead, 素粒子論グループ
素粒子論研究 / 素粒子論グループ [編], 20 Oct. 2007 - The importance and the sensitivity of the reaction 17O(n, γ)18O in the s-process nucleosynthesis
K. Yamamoto; T. Wada; M. Ohta; T. Nishimura; M. Y. Fujimoto; K. Kato; T. Suda; M. Aikawa, Lead, We apply our Monte Carlo method to the s-process element synthesis in the helium shell flash model for extremely metal-poor stars. We emphasize the importance of the reaction O-17(n gamma)O-18. It is presented that the uncertainty of this reaction rate affects the heaver elements abundance. We also discuss the variation of the O-Ne reaction paths with the uncertainty of the reaction rate of O-17(n gamma)O-18., AMER INST PHYSICS
AIP Conference Proceedings, 26 Feb. 2007 - Systematic study for the shell effect in the fission fragment mass distribution ruptured from neutron rich nuclei
M. Ohta; S. Tatsuda; K. Hashizume; K. Yamamoto; T. Wada; K. Sumiyoshi; K. Otuski; T. Kajino; H. Koura; S. Chiba and T. Tachibana, Science Direct
Nuclear Physics A, 2007 - Study on the dominant reaction path in nucleosynthesis during stellar evolution by means of the Monte Carlo method
K. Yamamoto; T. Wada; M. Ohta; T. Nishimura; M. Y. Fujimoto; K. Kato; T. Suda; M. Aikawa, Lead, We propose a Monte Carlo method to study the reaction paths in nucleosynthesis during stellar evolution. Determination of reaction paths is important to obtain the physical picture of stellar evolution. The combination of network calculation and our method gives us a better understanding of physical picture. We apply our method to the case of the helium shell flash model in the extremely metal poor star., AMER INST PHYSICS
AIP Conference Proceedings, 12 Jul. 2006
MISC
- Operation and Extension of IP Address Management Database with Network Access Authentication
宮北 和之; 山本 一幸; 青山 茂義; 三河 賢治
電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 26 May 2016 - 2011年度北海道大学原子核反応データベース研究開発センター年次報告
JCPRG Annual Report, Mar. 2012 - Observation/information disclosure system of environmental radiation
牧永 あや乃; 松本 琢磨; 椿原 康介; 山本 一幸; Odsuren Myagmarjav; 立石 謙太; 合川 正幸; 古立 直也; 加藤 幾芳; 木村 真明
日本原子力学会 年会・大会予稿集, 19 Oct. 2011 - コア励起を取り入れたM-Scheme Cluster Orbital Shell Model Approach
升井 洋志; 山本 一幸; 加藤 幾芳; 池田 清美
日本物理学会講演概要集, 01 Mar. 2010 - Particle capture reaction with core excitation in low energy
山本一幸; 升井洋志; 加藤幾芳
日本原子力学会 年会・大会予稿集, 2009
Lead - Microscopic Analysis of the neutron capture reaction near threshold energies
山本 一幸; 升井 洋志; 加藤 幾芳; 和田 隆宏; 太田 雅久
日本原子力学会 年会・大会予稿集, 2008 - S-process元素合成における17O(n,γ)180反応の重要性とその感度II
山本 一幸; 和田 隆宏; 太田 雅久; 加藤 幾芳; 升井 洋志
日本物理学会講演概要集, 28 Feb. 2007
Lead - r-process領域での核分裂片の質量分布II
龍田早苗; 山本一幸; 和田隆宏; 太田雅久; 住吉浩介; 大槻かおり; 梶野敏貴; 小浦寛之; 千葉敏; 有友嘉浩
日本物理学会講演概要集, 18 Aug. 2006 - s-process元素合成における17O(n，γ)18O反応の重要性とその感度
山本一幸; 和田隆宏; 太田雅久; 西村高徳; 藤本正行; 加藤幾芳; 合川正幸; 須田拓馬
日本物理学会講演概要集, 18 Aug. 2006
Lead - モンテカルロ法による元素合成経路の解析
山本 一幸; 橋詰 和明; 和田 隆宏; 太田 雅久; 西村 高徳; 須田 拓馬; 藤本 正行; 加藤 幾芳; 合川 正幸
日本物理学会講演概要集, 04 Mar. 2006
Lead - r-process領域での核分裂片の質量分布
龍田 早由; 山本 一幸; 和田 隆宏; 太田 雅久; 住吉 浩介; 大槻 かおり; 梶野 敏貴; 小浦 寛之; 千葉 敏
日本物理学会講演概要集, 04 Mar. 2006
Books and other publications
Lectures, oral presentations, etc.
- 新型コロナウイルス感染症の影響把握のためのIR活動を振り返って
嶌田 敏行、山本 一幸
R1：IR実務担当者セッション, 22 Mar. 2021, 大学評価コンソーシアム
20210322, 20210322 - 短期間での多要素認証への移行と定常運用に向けた業務の自動化
大瀧保広; 西原忠史; 山本一幸; 野口宏
第24回学術情報処理研究集会, 25 Sep. 2020, 国立大学法人情報系センター協議会
20200924, 20200925 - 茨城大学におけるダークネット宛通信のハニーポットによる分析と比較
戸谷 信暁; 米山 一樹; 大瀧 保広; 山本 一幸; 西原 忠史
2020年 暗号と情報セキュリティシンポジウム, 28 Jan. 2020
Research Themes
