• The Journal of the Acoustical Society of Korea
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• v.19 no.5
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• pp.9-12
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• 2000

Voice dialing system can recognize the speaker's command and dial the destinate phone number automatically. Such a system is useful for wireless handsets and portable communication devices. As a personal voice dialing system, all the commands are used to train the HMM for speech recognition based on owner-selected phrases. Its implementation requires much less memory space and computation resource compared to a speaker-independent system. Since only two or three training utterances per command are used in this system, it is difficult to estimate exact state duration distribution to improve the recognition performance. Therefore a post-processor is presented to improve the performance. Experiments which use the database collected through the telephone line showed that the proposed post-processor improves the recognition system performance.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.449-457
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• 2012

The purpose of this study is to investigate the relationship between radiation origin and health professionals, and to reduce exposed dose of radiation through efficient management. Increasing exposed dose of radiation to health professionals are caused by the increase of PET/CT use and a radioactive isotope. Hence, in this study, space dose from each origin of radiation generating was analyzed and the use of personnel protective clothing and shields was compared. As a result of this study, we confirmed that the exposed dose of radiation was much higher in case of wearing personnel protective clothing(0.5 mm pb) than no wearing personnel protective clothing under high energy gamma radiation(511 keV) of the position emitter($^{18}F$).

• Hwankyungkyoyuk
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• v.12 no.1
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• pp.335-347
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• 1999

Restricted by time and space, formal environmental education has a limit in accommodating fast changing socal phenomena and quickly spreading environmental problems. Therefore, to carry out more efficiently the environmental education for middle and high school students, this study is intended to search for a way to establish a network of formal and nonformal environmental education. More than 80% of civil environmental organizations replied they agree to establish a network of environmental education. As for the establishment of a network, they preferred the establishment in which middle and high school, civil environmental organizations, government, the environment-related departments of the universities. They preferred ‘civil environmental organizations’ for the operator, ‘local municipal or provincial level for the scale, ‘direct personal relations’ for the interchange method. To establish a network, they replied that ‘funding’, ‘specialists in environmental education’, ‘staff to proceed educations’, ‘reform of law and systems’ are required. They also preferred ‘funding from government budget’ for a way to fund a network. We can draw the following conclusions from the survey, We need a training program for environmental education staff not to make those educational programs by civil environmental organizations temporary Also, more studies should be done to establish more organized network of environmental education and nonformal environmental education by civil environmental organizations. Environmental problem varies depending on the local characteristics, and thus environmental education should be carried out locally at the network center for environmental education. Besides, local self-governing bodies should support it administratively and financially.

• Journal of Korean Elementary Science Education
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• v.18 no.2
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• pp.1-19
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• 1999

Based on the analysis of commonalities and differences in the views of science achievement in major reform documents in the United States and Korea, an aggregated view of science achievement is presented in this paper Science achievement is conceived of in terms of science content and science process. The components of science content include: (a) concepts and theories I n physical, life, and earth and space science;(b) science, mathematics, and technology;(c) science in personal and social perspectives;(d)history and nature of science;and (e) unifying themes. The components of science process include: (a) scientific understanding;(b) scientific investigation;(c) scientific communication; and (d) scientific habits of mind. The components of science process.cut across and intersect with the components of science content. The components of science achievement overlap and are related to one another. Despite such an overlap, understanding the rot e that each component plays provides insight into its unique contributions as well as its interactions with other components. A definition of science achievement and identification of its components based on major reform documents provides a guideline for science assessment as well a s science teaching and learning.

• ETRI Journal
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• v.31 no.6
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• pp.680-687
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• 2009

This paper reports on an improved piezoelectric microspeaker with a high sound pressure level of 90 dB, a total harmonic distortion of less than 15%, and coherence higher than 0.9. The fabricated Pb(Zr,Ti)$O_3$ (PZT) microspeakers have a thickness of only 1 mm including the speaker frame and an active area of 18 mm${\times}$20 mm. To achieve higher sound pressure and lower distortion, the PZT piezoelectric microspeaker has a well-designed speaker frame and a piezoelectric diaphragm consisting of a tilted PZT membrane and silicone buffer layer. From the simulation and measurement results, we confirmed that the silicon buffer layer can lower the first resonant frequency, which enhances the microspeaker's sound pressure at a low frequency range and can also reduce useless distortion generated by the harmonics. The fabricated PZT piezoelectric microspeakers are implemented on a multichannel speaker array system for personal acoustical space generation. The output sound pressure at a 30 cm distance away from the center of the speaker line array is 15 dB higher than the sound pressure at the neighboring region 30 degrees from the vertical axis.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.278-279
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• 2018

Crew on board perform their respective duties in a limited space. Personal factors and job stress affect job satisfaction of seafarers. In this study, it was conducted for a basic survey on relationship stress and satisfaction among the crew members' job stress factors. Job stress of crew who are responsible for the navigation was higher than that of managerial staff, and job satisfaction of navigating crew was also lower than managerial crew. In order to compensate for these results, it is necessary to change the recognition of the managerial personnel. It is necessary to develop and operate education programs to prevent these factors beforehand.

• Journal of Power Electronics
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• v.9 no.4
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• pp.654-666
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• 2009

Direct torque control (DTC) of induction machines (IM) is a well-known strategy of these drives control which has a fast dynamic and a good tracking response. In this paper a nonlinear DTC of speed sensorless IM drives is presented which is based on input-output feedback linearization control theory. The IM model includes iron losses using a speed dependent shunt resistance which is determined through some effective experiments. A stator flux vector is estimated through a simple integrator based on stator voltage equations in the stationary frame. A novel method is introduced for DC offset compensation which is a major problem of AC machines, especially at low speeds. Rotor speed is also determined using a rotor flux sliding-mode (SM) observer which is capable of rotor flux space vector and rotor speed simultaneous estimation. In addition, stator and rotor resistances are estimated using a simple but effective recursive least squares (RLS) method combined with the so-called SM observer. The proposed control idea is experimentally implemented in real time using a FPGA board synchronized with a personal computer (PC). Simulation and experimental results are presented to show the capability and validity of the proposed control method.

• IEMEK Journal of Embedded Systems and Applications
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• v.12 no.1
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• pp.11-18
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• 2017

Finite field arithmetic has been extensively used in error correcting codes and cryptography. Low-complexity and high-speed designs for finite field arithmetic are needed to meet the demands of wider bandwidth, better security and higher portability for personal communication device. In particular, cryptosystems in GF($2^m$) usually require computing exponentiation, division, and multiplicative inverse, which are very costly operations. These operations can be performed by computing modular AB multiplications or modular $AB^2$ multiplications. To compute these time-consuming operations, using $AB^2$ multiplications is more efficient than AB multiplications. Thus, there are needs for an efficient $AB^2$ multiplier architecture. In this paper, we propose a low latency Montgomery $AB^2$ multiplier using redundant representation over GF($2^m$). The proposed $AB^2$ multiplier has less space and time complexities compared to related multipliers. As compared to the corresponding existing structures, the proposed $AB^2$ multiplier saves at least 18% area, 50% time, and 59% area-time (AT) complexity. Accordingly, it is well suited for VLSI implementation and can be easily applied as a basic component for computing complex operations over finite field, such as exponentiation, division, and multiplicative inverse.

• International Journal of Advanced Culture Technology
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• v.7 no.4
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• pp.194-207
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• 2019

This paper is the author's personal experience and interpretation as a student whilst participating in Professor Kyung-Sook Shin's English Literature graduate course, "Literature and Technology II: Feminisms and Digital Humanities," during the 2019 spring semester at Yonsei University, South Korea. Exploring the intersections of literary feminist theory and digital humanities, this paper examines not only the content, but also the methodology and political effects of collaboratively digitally annotating Elizabeth Barrett Browning's epic novel/poem, Aurora Leigh (1856) through the medium, Google Docs. In particular, this paper observes the students' interaction with the digital tools and literature-related pedagogy in two main parts. First, the democratic political nature of classroom culture when creating a new language/code during annotation. Second, the coexistence of cyberspace and the physical classroom space and its effect on time, specifically in the archival of the past, influencing of the future, and the splitting into the present multiverse. From a student's perspective in digital literary annotation, this paper shows that technology could become a way to decolonize and reprogram education to be more inclusive and collaborative.

• Journal of Families and Better Life
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• v.20 no.1
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• pp.33-44
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• 2002

The purpose of this study is to define the concept of community based on the residential area and to review the issues on the research of community in related discipline area. The discourse about community has been developed in the field of social psychology, regional planning and architecture, housing studies, and research results by NGO. These studies of community has been dealt with social interaction and norm as well as the physical aspects of community. The research on community has been studied with the approach of structure and functionalist, systems theory approach, conflict theory approach, ecological approach, microsociological approach, and social construction approach. However, these approaches have not integrated together, but recognized community in a social or personal context. The social construction approach among these approaches suggest a useful conceptual framework for studying community in the point of view that social condition changes according to the autonomic individual. Understanding of community will influence to establishing a community norm, to planning a communal space, and to developing strategies of community. And it also takes a Important role t\ulcorner change the housing policy, institution and life style.