• Journal of KIISE:Computer Systems and Theory
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• v.35 no.7
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• pp.327-331
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• 2008

Optimal Extension Fields (OEFs) are finite fields of a special form which are very useful for software implementation of elliptic curve cryptosystems. Bailey and Paar introduced efficient OEF arithmetic algorithms including the $p^ith$ powering operation, and an efficient algorithm to construct OEFs for cryptographic use. In this paper, we give a counterexample where their $p^ith$ powering algorithm does not work, and show that their OEF construction algorithm is faulty, i.e., it may produce some non-OEFs as output. We present improved algorithms which correct these problems, and give improved statistics for the number of OEFs.

• KOREAN POULTRY JOURNAL
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• v.42 no.5
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• pp.105-109
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• 2010

종축업 등록제 시행으로 종계장은 큰 폰 증가했지만, 과거 허가제였던 종축업에 대한 법적 자율성을 부여하기 위해 등록제로 전환되면서 영세한 농가들의 참여로 전문성이 떨어지고, 질병에 노출되면서 생산성이 하락하는 결과를 낳았다. 총 509 농가 종계장 가운데 등록종계장은 373 개소 (73.3%)와 미등록종계장중 육성전문농장은 25개소 (4.9%), 성계사육농장은 111개소 (21.8%)를 차지하면서 (2010년 2월 기준) 종계시육시설이 노후화되거나 미비한 농가에 대한 정부차원의 관리가 이루어지지 않는 것이 현실이다. 정부는 국내 양계산업 생산성을 높이기 위한 방안으로 종축장의 위생수준과 종축 능력 향상을 위해 지난해 종돈장에 이어 올해 초 종계장을 대상으로 '우수종계장 종합평가사업'을 진행했다. 주최 농림수산식품부, 주관 국립축산과학원, 시행기관은 종축개량협회(종돈)와 대한양계협회(종계)에서 진행한 이번 사업은 우수농장을 꼽아 시설 및 운영자금에 대한 인센티브를 제공해 1차 산업의 전문화와 청정화를 가속화해 종계장간의 자율경쟁을 유도할 뿐만 아니라 종계장 평가를 통해 양계농가에 종계 선택 지표를 제공한다는 계획이다. 지난해 말부터 대한양계협회를 비롯해 국립축산과학원, 국립수의과학검역원, 한국계육협회, 농협중앙회에서는 신청한 농가를 대상으로 평가에 참여한 32개 농가 중 서류심사를 통과한 16개 농가를 대상으로 실사위원이 현지 점검을 통해 지난 3월 19일 총 7개의 우수종계장을 선발했다. 본지를 통해 종계장의 평가기준에 따라 현장 실시를 통해 선정된 총7개소 농장을 소개해 농가 선택지표에 도움을 주고자 소개하고자 한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.15 no.12
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• pp.981-989
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• 1990

Thos paper summarized previously proposed several public key distribution systems and proposes a new public key distribution system to generate an common secret conference key for public key distribution systems three or more user. The now system is based on discrete exponentiation, that is all operations involve reduction modulo p for large prime p and we study some novel characteristics for computins multiplicative inverse in GF(p). We use one-way communication to distribute work keys, while the other uses two-way communication. The security of the new system is based on the difficulty of determining logarithms in a finite field GF(p) and stronger than Diffie-Hellman public key distribution system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1C
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• pp.21-27
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• 2009

We present an efficient exponentiation algorithm for a finite field $GF(2^n)$ determined by an optimal normal basis of type II using signed digit representation of the exponents. Our signed digit representation uses a non-adjacent form (NAF) for $GF(2^n)$. It is generally believed that a signed digit representation is hard to use when a normal basis is given because the inversion of a normal element requires quite a computational delay. However our result shows that a special normal basis, called an optimal normal basis (ONB) of type II, has a nice property which admits an effective exponentiation using signed digit representations of the exponents.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.4
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• pp.97-104
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• 2005

Vision-based lane sensing systems require accurate and robust sensing performance in lane detection. Besides, there exists trade-off between the computational burden and processor cost, which should be considered for implementing the systems in passenger cars. In this paper, a stereo vision-based lane detection system is developed with considering sensor configuration aspects. An inverse perspective mapping method is formulated based on the relative correspondence between the left and right cameras so that the 3-dimensional road geometry can be reconstructed in a robust manner. A new monitoring model for estimating the road geometry parameters is constructed to reduce the number of the measured signals. The selection of the sensor configuration and specifications is investigated by utilizing the characteristics of standard highways. Based on the sensor configurations, it is shown that appropriate sensing region on the camera image coordinate can be determined. The proposed system is implemented on a passenger car and verified experimentally.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.265-270
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• 2009

In October 2009, hunting billbug, Sphenophorus venatus vestitus Chittenden, was first found on zoysiagrass at Yongweon country club in Jinhae. The adult was 6~11mm long and dark brown to black color. The pronotum is coarsely punctate except for a "Y"-shaped area in the center and a parenthesis-like marking on each side. This pattern is characteristic of the species. This billbug feeds on warm-season grasses like zoysiagrass and Burmudagrass. As the hunting billbug is one of the plant quarantine pests in Korea, the National Plant Quarantine Service surveyed additional occurrence for neighboring golf courses and some turfgrass farms, but not found yet.

• The Southeast Asian review
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• v.21 no.2
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• pp.1-41
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• 2011

Southeast Asia developed maritime trade from the early period due to the suitable physical and cultural conditions. The land consists of peninsular and archipelago, and located at the junction of the two monsoons in South China Sea and India Ocean. The people inherit cultural openness to receive outer influences positively. When Portuguese came to Southeast Asia in 16th century, the region had already enjoyed certain level of commercial development and sociocultural dynamics through the long time experience of interactions with outer world. The Portuguese contact to Southeast Asia was more of participation and assimilation than of conquest and rule experienced in South America. It was due to the higher level of spiritual and material civilization existed in Southeast Asia. Portuguese brought several new elements into Southeast Asia such as colonization and new weapons, Cartaz system and commercial monopoly, and Catholic mission and Casado policy. These new elements, however, did not impact much on the existing Maritime trade that played an important role to change the sociocultural structure of Southeast Asia. Even though Portuguese contact itself did not make significant differences in Southeast Asia, it was meaningful in a sense that it opened a path and left a model case for the more powerful Europeans who came soon after her.

• Iberoamérica
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• v.23 no.2
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• pp.135-178
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• 2021

A teacher's talk does not make a simple delivery of information. It reflects the role of the teacher, since the language used by a teacher intervenes in a crucial way in the complex mechanisms that underlie teaching and learning of foreign languages. In this sense, the ways in which teachers give feedback have an impact on the process, not only of learning, but also of teaching. The important role of emotional factors in learning has resonated strongly in the intuition of many second and foreign language teachers. As a result, over the past three decades, research on foreign language acquisition has confirmed the hypothesis that language learning is enhanced by rapport between teacher and student. This study analyses the positive feedback given by native Spanish teachers in the context of university classes in Korea. The positive words from a language teacher are related to forming emotional factors such as motivation, attitude, interest, self-confidence, self-esteem, anxiety, and empathy, which directly influence in the acquisition of Spanish. 35 hours of oral practical classes taught by three native teachers of Colombian, Spanish and Mexican nationality were examined. According to the result, almost all the correct answers from students were corresponded with some type of positive feedback. The most frequent strategies are making a compliment, an approval, a repetition, and laughter or non-verbal cues. It is interesting to observe that teachers don't use only a single strategy to provide positive feedback, but instead combine multiple ways to enrich the positiveness of the feedback.

• Iberoamérica
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• v.23 no.2
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• pp.179-208
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• 2021

Luis Humberto Crosthwaite, as a witness to the accelerated changes in Tijuana since the 80's, has built a chronicle of the city based on nostalgia, fantasy, popular language, music, and criticism of the inequality between both sides of the border, but above all, on humour and irony. Among the gallery of characters that populate his stories, the common resident of the border has a special place. Here we are not talking about the passing person or newcomers, but of those who have shaped their social and personal identity from a long every day relationship with the city and the borderline, which makes up what we will call the border-being. In this work, we dialogue with the psychoanalytic concept of border personality or borderline disorder, which refers in a general way to subjects with a deep fracture between the self and the being, which prompts a psychotic search to reconcile this division. In addition, we will engage in an interdisciplinary dialogue to analyse how Crosthwaite characterises the fracture of the border-subjects in some of the stories of the book Instrucciones para cruzar la frontera, to point out the psychosis caused by the sociocultural tensions of life in a border city like Tijuana.

• Iberoamérica
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• v.23 no.2
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• pp.209-241
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• 2021

Over the last few years, rural areas in northeastern Mexico have present significant changes in social, economic, and territorial aspects linked to the New Rurality. In this context, winemaking has become one of the most dynamic and growing activities in the regional economy. This emerging development has prompted different forms of appropriation and use of this space, but it also highlights the lack of access to knowledge for wine production due to the lack of formal educational centers. As a result, learning communities enable the development of skills and competencies through non-formal educational practices. The objective of this paper is to analyze the role of learning communities in non-formal educational environments, taking as a case study: a collective of small-scale wine producers in Parras de la Fuente, Coahuila. This research focuses on two perspectives of learning: appropriation and technology transfer, and promotion of Mexican wine culture. The main finding was to demonstrate the importance of including educational processes that respond to the context and needs of the community.