• Title/Summary/Keyword: minimal field extension

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Where Some Inert Minimal Ring Extensions of a Commutative Ring Come from

  • Dobbs, David Earl
    • Kyungpook Mathematical Journal
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    • v.60 no.1
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    • pp.53-69
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    • 2020
  • Let (A, M) ⊂ (B, N) be commutative quasi-local rings. We consider the property that there exists a ring D such that A ⊆ D ⊂ B and the extension D ⊂ B is inert. Examples show that the number of such D may be any non-negative integer or infinite. The existence of such D does not imply M ⊆ N. Suppose henceforth that M ⊆ N. If the field extension A/M ⊆ B/N is algebraic, the existence of such D does not imply that B is integral over A (except when B has Krull dimension 0). If A/M ⊆ B/N is a minimal field extension, there exists a unique such D, necessarily given by D = A + N (but it need not be the case that N = MB). The converse fails, even if M = N and B/M is a finite field.

Basis Translation Matrix between Two Isomorphic Extension Fields via Optimal Normal Basis

  • Nogami, Yasuyuki;Namba, Ryo;Morikawa, Yoshitaka
    • ETRI Journal
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    • v.30 no.2
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    • pp.326-334
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    • 2008
  • This paper proposes a method for generating a basis translation matrix between isomorphic extension fields. To generate a basis translation matrix, we need the equality correspondence of a basis between the isomorphic extension fields. Consider an extension field $F_{p^m}$ where p is characteristic. As a brute force method, when $p^m$ is small, we can check the equality correspondence by using the minimal polynomial of a basis element; however, when $p^m$ is large, it becomes too difficult. The proposed methods are based on the fact that Type I and Type II optimal normal bases (ONBs) can be easily identified in each isomorphic extension field. The proposed methods efficiently use Type I and Type II ONBs and can generate a pair of basis translation matrices within 15 ms on Pentium 4 (3.6 GHz) when $mlog_2p$ = 160.

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CLASS FIELDS FROM THE FUNDAMENTAL THOMPSON SERIES OF LEVEL N = o(g)

  • CHOI So YOUNG;Koo JA KYUNG
    • Journal of the Korean Mathematical Society
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    • v.42 no.2
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    • pp.203-222
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    • 2005
  • Thompson series is a Hauptmodul for a genus zero group which lies between $\Gamma$o(N) and its normalizer in PSL2(R) ([1]). We construct explicit ring class fields over an imaginary quadratic field K from the Thompson series $T_g$($\alpha$) (Theorem 4), which would be an extension of [3], Theorem 3.7.5 (2) by using the Shimura theory and the standard results of complex multiplication. Also we construct various class fields over K, over a CM-field K (${\zeta}N + {\zeta}_N^{-1}$), and over a field K (${\zeta}N$). Furthermore, we find an explicit formula for the conjugates of Tg ($\alpha$) to calculate its minimal polynomial where $\alpha$ (${\in}{\eta}$) is the quotient of a basis of an integral ideal in K.

Efects of Biodegradable Mulching Films Containing Rice Powder on Sweetpotato Growth (쌀 분말이 함유된 생분해성 멀칭필름이 고구마 생육에 미치는 영향)

  • Sin Young Park;Ju Hyun Im;Eun Byul Go;Kil Ja Kim;Jae Min Park;Dong Kwan Kim
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.69 no.2
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    • pp.123-132
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    • 2024
  • In this study, two types of biodegradable film prototypes were produced using plastic resin containing rice powder. The application of these biodegradable films in sweetpotato (Ipomoea batatas L. Lam) fields and their impacts of plant growth, yield, and the soil environment were assessed, in comparison with Polyethylene (PE) film. The light transmittance of the biodegradable film containing 30% of 350 mesh rice powder (BF30-350RP) was 0.8%, which was lower than the 2.0% light transmittance of the biodegradable film containing 40% of 500 mesh rice powder (BF40-500RP) and 2.7% light transmittance of PE film. Surface temperature measurements on clear day indicated that the PE film exhibited the lowest temperature, with the minimal difference observed between BF40-500RP and BF30-350RP. Assessment of the damage ratio resulting from agricultural work revealed a ranking of 0.4% for the PE film, 3.3% for BF500-400RP, and 5.3% for BF350-30RP. Visible decomposition of BF40-500RP and BF30-350RP commenced after 40 and 30 days of outdoor exposure, reaching 62.3% and 70.4% decomposition at 90 days post-exposure, respectively. The decomposition of biodegradable films applied to sweetpotato fields progressed more slowly in BF40-500RP than in BF30-350RP. The BF40-500RP film on the surface of the ridges was decomposed by 5%, 30%, 55%, and 90% after 30, 60, 90, and 120 days after planting sweetpotato cuttings, respectively. Both types of biodegradable films at the ridge and furrow borders were completely decomposed after 75 days of sweetpotato planting. In a field where the surface was sealed by mulching without growing sweetpotatoes, the soil moisture and its deviation were lower in the order of PE film, BF40-500RP, and BF30-350RP, but the differences were not significant. The soil temperature was higher for PE film mulching than for the biodegradable films containing rice powder, but the differences were small. Two months after sweetpotato planting, the daily average soil moisture decreased by 2.5%point for BF30-350RP mulching, 1.5%point for BF40-500RP mulching, and 1.1%point for PE film mulching over seven days. Soil temperature was similar for both biodegradable film mulches, but increased steadily for the PE film mulch, reaching a daily average of 0.1℃ higher than for the biodegradable films. Sweetpotato vine growth and tuber yield were similar for all the mulching films tested.

A Study of Mobile Patient Identification System Using EM4095 (EM4095를 이용한 모바일 의료환자인식 시스템 연구)

  • Jo, Heung-Kuk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.10
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    • pp.2337-2342
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    • 2010
  • There is a vast field of application for RFID(Radio Frequency IDentification) technology. In the case of hospitals, RFID can be used for organizing patient data. Generally, patient data has been handled with medical cards. In order to look up data about a patient, the medical card would have to be found first, within a lot of other medical cards, by hand or with a computer. This is a very inconvenient system. Also, if the card is searched by the name of the patient, fatal medical accidents may occur in cases of mix-ups. If remote RFID Tag monitoring systems are applied in this case, the patient data would be accessible in the hospital. This article will discuss the grafting of RFID systems and wireless data communicating technology. The EM4095 chip, which uses 125KHz carrier waves was used in this study. And a Bluetooth module was added for wireless data communication. The ATMEGA128 microcomputer was used to control the RFID system and wireless module. A LCD monitor was connected to the extension port for nurses to view patient data, and also, the same information was displayed on PC monitors for doctors to see. The circuit was designed to consume minimal amounts of electricity for portability, and to transmit Tag ID's in environments with a lot of noise. The article is concluded with a diagram of the whole system, and performance of each data transmitting section has been analyzed.

A study of the development of the public libraries in the "Chun-Buk" province in Korea (전북지역 공공도서관의 발전책에 관한 연구)

  • 김포옥
    • Journal of Korean Library and Information Science Society
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    • v.15
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    • pp.25-77
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    • 1988
  • A Library is the fundamental character of culture in a country and it is also a barometer of culture in its community. Every cultural reality, however, can hardly come to fruition in a short time and so, it will be effected through a long time and tradition. This study aims at catching up how the above-mentioned public libraries have an influence on culture of its community people. For this purpose, the actual conditions of the public libraries have been investigated and analyzed and as a result of it, the problems have been reilluminated from the nation-wide point of view. And in the new changes, developing improvement measures have been tried to find. How to study was on the basis of the actual materials of the on the-spot survey, the interviews with the working officials and the response by way of questionnaire. Summing up the investigated and analyzed contents are as followings. In the above mentioned province, therefore, number of the public libraries are very limited compared with number of the people. And so, it is very essential to increase the public libraries in the province. In terms of the actual conditions, the public libraries lags far behind the other provinces in Korea from this library field. The present chronic conditions are the budgetary deficit, the collections insufficient to the legal minimal standards, the lack of professional librarians ignorance of the people and library managements by unprofessionals, etc.. This hinders the progress of the public libraries and to seculate them from the people. The improvements and the solutions to the above-mentioned problems are as follows. 1. To recruit the personnel sufficient to the legal standards and to reorganize the offices and to turn upward the highest class of librarian's position above the 4th class. 2. To secure collections sufficient to the legal standards and to strang then the extension services. 3. To organize the council composed of the chief librarians of the public libraries including the working chiefs in the province and to develop the works-in-hand of the libraries from the level of decision-making. 4. To organize the librarian training group and to study the working problems and to seek the qualified improvement of librarians. 5. The management of the public libraries in the province are, at present, der the Ministry of Education and the local government takes the financial power. So both should be shortly unified. 6. To do regularly the course of how to use library materials for the community people and to seek the inducement measures for the people through the various cultural events. 7. The public libraries organize the mutual cooperation networks and to seek the system automatized plans of free use of library materials and every library works. 8. To enlarge book mobile system actively and to infiltrate into the daily living of people deeply. Finally, what the present writer would like to speak to the chief librarians of the public libraries the human aspects of librarians should not be ignored no mater how excellent a library organization may be. In addition to this, the present writter is sure that the far-reached future of our library organization will depend on the librarians.

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"Poor Theatre, Poor Art" - Jerzy Grotowsky's Play and Arte Povera ('가난한 연극, 가난한 미술' - 그로토프스키 연극이론과 아르테 포베라)

  • Kang, Young-Joo
    • The Journal of Art Theory & Practice
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    • no.5
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    • pp.109-133
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    • 2007
  • What a concept of theatricality in modern art became more controversial is through a review "art and object-hood" on Michael Fried's minimal art, as having been already known broadly. As he had been concerned, the art following the minimalism is accepting as the very important elements such as the introduction of temporality, the stage in the exhibition space, and the audience's positive participation, enough to be no exaggeration to say that it was involved in almost all the theatricality. Particularly even in the installation art and the environment art, which have substantially positioned since the 1970s, the space is staged, and the audience's participation is greatly highlighted due to the temporal character and the site-specific in works. In such way, the theatricality in art work is today regarded as one of the most important elements. In this context, it is thought to have significance to examine theatricality, which is shown in the works of Arte Povera artists, who had been active energetically between 1967-1971. That is because the name of this group itself is what was borrowed from "Poor Theatre" in Jerzy Grotowski, who is a play director and theorist coming from Poland, and because of having many common points in the aspect of content and form. It reveals that the art called Arte Povera is sharing many critical minds in the face of commanding the field called a play and other media. Grotowski's theatre theory is very close to the theory and substance in Arte Povera in a sense that liberates a play, which was locked in literature, above all, renews the relationship between stage and seat and between actor and audience, and pursues a human being's change in consciousness through this. That is because Arte Povera also emphasizes the communication with the audience through appealing to a human being's perception and through the direct and living method, not the objective art concept of centering on the work. In addition, the poor play or poor art all has tendency that denies a system, which relies upon economic and cultural system, and seeks for what is anti-cultural, elemental, and fundamental. It is very similar even in a sense that focuses on the exploration process itself rather than the result, excludes the transcendental concept, and attaches importance to empiricism. However, Arte Povera accepts contradictoriness and complexity, and suggests eclecticism and tolerance, thereby being basically the nomadic art and the art difficult to be captured constitutively. On the other hand, there is difference in a sense that the poor play is characterized by purity, asceticism, seriousness, and solemnity. If so, which significance does this theatricality, which was introduced to art, ultimately have? As all the arts desire to be revealed with invisible things beyond the visual thing, theatricality comes to play a very important role at this time. If all the artists and audiences today came to acquire actual or virtual freedom much more, that can be said to be a point attributable to that art relied upon diverse conditions in a play.

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