• ETRI Journal
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• v.31 no.5
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• pp.625-627
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• 2009

This letter describes an improved side-channel attack on DES with the first four rounds masked. Our improvement is based on truncated differentials and power traces which provide knowledge of Hamming weights for the intermediate data computed during the enciphering of plaintexts. Our results support the claim that masking several outer rounds rather than all rounds is not sufficient for the ciphers to be resistant to side-channel attacks.

• ETRI Journal
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• v.32 no.2
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• pp.333-335
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• 2010

This letter proposes a non-coherent blind time-of-arrival (TOA) estimation scheme for impulse radio ultra-wideband systems. The TOA estimation is performed in two consecutive phases: the Rayleigh-quotient theorem-based coarse-signal acquisition (CSA) and the iterative-threshold-test-based fine time estimation (FTE). The proposed scheme serves in a blind manner without demanding any a priori knowledge of the channel and the noise. Analysis and simulations demonstrate that the proposed scheme significantly increases the signal detection probability in CSA and ameliorates the TOA estimation accuracy in FTE.

• ETRI Journal
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• v.34 no.1
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• pp.142-145
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• 2012

The main challenge at present in constructing hierarchical identity-based encryption (HIBE) is to solve the trade-off between private-key size and ciphertext size. At least one private-key size or ciphertext size in the existing schemes must rely on the hierarchy depth. In this letter, a new hierarchical computing technique is introduced to HIBE. Unlike others, the proposed scheme, which consists of only two group elements, achieves constant-size private keys. In addition, the ciphertext consists of just three group elements, regardless of the hierarchy depth. To the best of our knowledge, it is the first efficient scheme where both ciphertexts and private keys achieve O(1)-size, which is the best trade-off between private-key size and ciphertext size at present. We also give the security proof in the selective-identity model.

• Korean Journal of Oriental Medicine
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• v.14 no.2
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• pp.151-154
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• 2008

"EuiBangYooChui"(Classified Assemblage of Medical Prescriptions) preserves important historical documents about herbal medical prescriptions up to the beginning of Ming dynasty. Mikisakae, a well-known medical history scholar of Japan, attributed high values on "EuiBangYooChui"(Classified Assemblage of Medical Prescriptions) as he stated that it summarized all medical knowledge of all over China and promulgated korean medicine to world top level. "EuiBangYooChui"(Classified Assemblage of Medical Prescriptions) thoroughly cited herbal prescriptions of 150 medical books of China which contents reach up to 9.5millions of letters. Also clarified all the sources of its contents. These efforts made easy the utilization for upcoming experts. Existing block books serves in various aspects of philological field, such as revision of lost documents, block book studies, contents studies, medical history studies, letter studies, phoneme studies and scholia.

• Journal of Family Resource Management and Policy Review
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• v.5 no.2
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• pp.59-67
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• 2001

Pu-lei is a well-known translator in Chinese literature. He had delivered his experience, knowledge and paternal love to his son who was studying abroad, by hundreds of letters from 1954 to 1966. These letters are appreciated as the perfect expression for paternal love and concerns. Although he had experienced both cultures of the West and the East, his lessons for son are rooted in the oriental‘sprit training’. What he emphasized in his letters is that one should put sound personality first than merely enhancing abilities. Especially, he valued the recreation from meditation and living up to one's belief. Furthermore, he had taught his son to observe the properties, to manage time, and pride of his country and patriotism. The modern family education has overlooked the enhancement of human nature. The egoistic and jaundiced parental love and over-protectiveness led the disorder and the absence of morality today. In this point, the lessons from Pu-lei's letter will give us important suggestions.

• The Journal of Korea Robotics Society
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• v.14 no.4
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• pp.348-356
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• 2019

The backdrivable servovalve is a desirable component for force and interaction control of hydraulic actuation systems because it provides direct force generation mechanical impedance reduction by its own inherent backdrivability. However, high parametric uncertainty and friction effects inside the hydraulic actuation system significantly degrade its advantage. To solve this problem, this letter presents a disturbance-adaptive robust internal-loop compensator (DA-RIC) to generate ideal interactive control performance from the backdrivable-servovalve-based system. The proposed control combines a robust internal-loop compensator structure (RIC) with an explicit disturbance estimator designed for asymptotic disturbance tracking, such that the controlled system provide stable and ideal dynamic behavior for impedance control, while completely compensating the disturbance effects. With the aid of a backdrivable servovalve, we show that the proposed control structure can be implemented based on a simplified nominal model, and the controller enables implementation without accurate knowledge of the target system parameters and disturbances. The performance and properties of the proposed controller are verified by simulation and experiments.

• Iberoamérica
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• v.14 no.2
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• pp.119-145
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• 2012

This paper deals with the study of how the 'birth' of Brazil happened and how the European utopianism was represented in Brazilian Informative Literature of the sixteenth century, that is, the first literary manifestations of Brazil. There were at that time the Renaissance humanism and the scientific development that encouraged dozens of illustrious navigators for new discoveries ultra-seas, like Christopher Columbus who discovered America. Writings such as Letter to King Manuel of Pero Vaz de Caminha, had mostly an intention to inform Europeans about climates, indians and possibility to discover gold or silver. Main narrative characteristics were uncertainty and exageration, which ironically helped to attract more discoveries and explorations in the New World. Americo Vespucio's Mundus Novus inspired Thomas More to write Utopia, in which the author described through a Portuguese sailor the ideal but unrealizable society. Utopianism regarding the imaginary island of 'Brazi', well known among Europeans since long ago, may have influenced the current name of the country: 'Brazil'. On the other hand, utopianism shown in Brazilian Informative Literature worked as a justification for Europeans to explore and colonize the New World.

• Journal of Korean Public Health Nursing
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• v.19 no.1
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• pp.74-94
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• 2005

The purpose of this study was to compare the effect of education between CAI(Computer Assisted Instruction) and lectures for smoking cessation among male students who attended vocational high schools. Conducted from February 24th to April 26th, 2003, the study design was quasi-experimental with nonequivalent control group pretest-posttest design. The study subjects were 60 male students in K vocational high school in Daegu city, who were present smokers and had more than 7.0 ppm concentration level of carbon monoxide. Thirty students were randomly chosen as the experimental group which applied CAI education method for smoking cessation. The other 30 students served as the control group which received lecture education method of 40 minutes on four consecutive days. CAI education for smoking cessation was composed of ready-made individual learning contents, counseling by using cyber-communication, writing a letter to stop smoking, and writing a written agreement for smoking cessation. Lecture education for smoking cessation was composed of a ready-prepared lecture for the group, writing a letter to stop smoking, and writing a written agreement for smoking cessation. To measure smoking related knowledge, Jeong Ree Roh(1996)'s smoking related knowledge scale$(Cronbach's\;{\alpha}=0.84)$ was modified and used by the researcher. To measure smoking related attitude, Jeong Ree Roh(1996)'s smoking related attitude scale$(Cronbach's\;{\alpha}=0.91)$ was modified and used by the researcher. Smoking related knowledge scale's Cronbach's $\alpha$ was 0.83 in the pilot study and 0.93 in this study. Smoking related attitude scale's Cronbach's a was 0.80 in the pilot study and 0.98 in this study. To determine the smoking amount, the number of cigarettes smoked per day was checked. The concentration level of CO in the exhaled breath was measured (Micro CO Cat. No. MCO2, UK). Data was analyzed by $x^2-test$, t-test, repeated measures ANOVA. simple main effects, and time contrast test with SPSS/Win 11.0 program. The results of this study were as follows: 1. The first hypothesis. that 'Smoking-related knowledge score in the experimental group by using CAI education for smoking cessation will be higher than that in the control group by using lecture education for smoking cessation', was not supported. 2. The second hypothesis, that 'Smoking-related attitude in the experimental group by using CAI education for smoking cessation will be higher than that in the control group by using lecture education for smoking cessation'. was supported(F=6490.79. p=0.000). 3. The third hypothesis. that 'Smoking amount in the experimental group by using CAI education for smoking cessation will be less than that in the control group by using lecture education for smoking cessation'. was supported. 1) The third-1st sub-hypothesis. that 'The number of cigarettes smoked per day in the experimental group by using CAI education for smoking cessation will be less than that in the control group by using lecture education for smoking cessation'. was supported(F=134.19. p=0.000). 2) The third-2nd sub-hypothesis. that 'The concentration level of CO by ppm per one exhaled breath in the experimental group by using CAI education for smoking cessation will be lower than that in the control group by using lecture education for smoking cessation"' was supported(F=268.55. p=0.000). From the above results. CAI education can be an effective intervention to improve smoking-related knowledge and attitude. and to reduce the number of cigarettes smoked per day and the concentration level of CO by ppm per one exhaled breath. Lecture education can be effective to improve smoking-related knowledge. In the future, when CAI education and lecture education for smoking cessation are applied on the school nursing field. the students can gain a comprehensive understanding of smoking cessation, changes in smoking-related knowledge. smoking-related attitude and reducing smoking amount. Furthermore, CAI education for smoking cessation could be developed as an individual self initiative program and could give a guideline to apply CAI education for smoking cessation in other field.

• Journal of the Korean Dietetic Association
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• v.16 no.1
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• pp.39-48
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• 2010

This study was conducted to assess the perception of nutritional education by students in elementary school and their parents in terms of the degree of satisfaction with school foodservices. The survey was conducted on 322 parents and 322 students using a questionnaire. Most of the students and parents were satisfied with the school foodservices, the most satisfactory component of school foodservice was the "balanced nutrition intake". The students and parents acquired nutritional information from the "school letter" and "Mass media". They trusted professional dietitians, the school and the nutritional information acquired from accredited mass media. In regards to the type of nutritional education, 28.9% of parents preferred "clinical nutrition information on disease" and 26.9% of parents preferred "nutrition information of food". In contrast, 33.7% of the students preferred the "clinical nutrition information on disease" and 25.4% of the students preferred "right eating habit (unbalanced eating, skipping meal)". The top three reasons for wanting to provide offspring with nutritional information was "right eating habit" (48.9%), "correction of unbalanced diet" (19.8%) and "healthy physical strength" (12.1%). The dietitians need professionalism to deliver accurate information and knowledge relating to the subjects that the users demand and the development of teaching media should be conducted to effectively deliver this knowledge.

• Child Studies in Asia-Pacific Contexts
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• v.4 no.1
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• pp.47-63
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• 2014

The purpose of this study was to develop a screening test for children at risk of reading underachievement and to investigate the effectiveness of the early-stage intervention program. In the first part of the study, we recruited 155 elementary first grade students for a screening test. Phonological deletion, digit naming, object naming, and sound-letter correspondence knowledge of a screening test, all assessed at the beginning of the school year, predicted the reading ability at the end of the school year. In the second part of the study, we analyzed the difference in the reading ability between fourteen children who participated in the intervention program and eighteen non-participating children. Reading ability was assessed by evaluating word recognition, oral reading fluency, reading comprehension, and pseudo-word recognition. The reading ability of intervention group improved more compared to control group, and the difference between two groups accentuated over time. However, final analysis conducted in November revealed that two groups did not differ significantly in oral reading fluency. This suggests that, unlike word recognition and comprehension, fluency might not dramatically improve in a short period.