• Journal of the Optical Society of Korea
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• v.20 no.6
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• pp.722-732
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• 2016

A new optical one-time password (OTP) authentication method using digital holography is proposed, which enhances security strength in the authentication system. A challenge-response optical OTP algorithm based on two-factor authentication is presented using two-step phase-shifting digital holography, and two-way authentication is also performed using challenge-response handshake in both directions. Identification (ID), password (PW), and OTP are encrypted with a shared key by applying phase-shifting digital holography, and these encrypted pieces of information are verified by each party by means of the shared key. The encrypted digital holograms are obtained by Fourier-transform holography and are recorded on a CCD with 256 quantized gray-level intensities. Because the intensity pattern of such an encrypted digital hologram is distributed randomly, it guards against a replay attack and results in higher security level. The proposed method has advantages, in that it does not require a time-synchronized OTP, and can be applied to various authentication applications. Computer experiments show that the proposed method is feasible for high-security OTP authentication.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.6
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• pp.1070-1075
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• 2006

TETRA system provides the radio authentication service which permits only authorized radio to access network. Radio authentication is the process which checks the sameness of authentication-key(K) shared between radio and authentication center by challenge-response protocol. TETRA standard authentication protocol can prevent the clone radio to copy ISSI from accessing network, but can't prevent the clone radio to copy ISSI & authentication-key. This paper analyzes authentication-key generation/delivery/infection model in TETRA authentication system and analyzes the threat of clone radio caused by authentication-key exposure. Finally we propose the new authentication protocol which prevent the clone radio to copy ISSI & authentication-key from accessing network.

• Biomolecules & Therapeutics
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• v.2 no.4
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• pp.331-335
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• 1994

As a part of the safety evaluation of Pseudomonas vaccine(CFC-101), antigenicity tests were carried out in guinea pigs and mice. In active systemic anaphylaxis(ASA) test, guinea pigs showed no sign or only moderate sign(1/5) when sensitized and challenged with up to 200 $\mu\textrm{g}$/kg. In homologous passive cutaneous anaphylaxis(PCA) test using guinea pigs, inoculation of CFC-101 alone did not produce CFC-101-specific antibody. When inoculated with 200 $\mu\textrm{g}$/kg plus adjuvant, challenge of 200 $\mu\textrm{g}$/kg produced PCA titer of 32(5/5) but challenge of 20 $\mu\textrm{g}$/kg did not produce CFC-101-specific antibody. In heterologous PCA test using mice, CFC-101-specific antibody was not detected when sensitized with CFC-101 alone. Some animals(3/12) showed positive PCA response when inoculated with 200 $\mu\textrm{g}$/kg plus alum. In passive hemagglutination (PHA) test, although no antibody was detected at 20 $\mu\textrm{g}$/kg, inoculation of 200 $\mu\textrm{g}$/kg alone or with alum produced positive response in all animals. This result has already been predicted because CFC-101 is a vaccine developed for the purpose of immunization. From the above results, it can be concluded that there is no adverse antigenic potential up to 10 times clinical dose of 200 $\mu\textrm{g}$/kg.

• Clinical and Experimental Pediatrics
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• v.46 no.5
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• pp.495-499
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• 2003

Purpose : Eosinophil is one of the important inflammatory cell involved in the airway inflammation in childhood asthma. It has been demonstrated that markers of eosinophil activation, including eosinophil cationic protein or eosinophil protein X(EPX), are increased in childhood asthma. Furthermore, they are related to disease activity and are assumed to be helpful in monitoring the treatment effect as urinary EPX(U-EPX) can be obtained easily and in a noninvasive way in children of all ages. Methods : Twenty-five children(22 male and three female) aged $11.87{\pm}3.82$ years with stable asthma were challenged with methacholine and urine was collected from each child during the following periods; before methacholine challenge test(MCT); 0-3 hr after the end of MCT; 4-7 hr after the end of MCT; and 8-24 hr after the end of MCT. Bronchial reactivity was determined by using Dosimeter( Jeager, Germany) with serially diluted methacholine from 0.05 to 25.0 mg. The $FEV_1$ less than 80% of baseline value were classified into positive MCT. U-EPX was measured with a sensitive and specific radioimmunoassay(Pharmacia & Upjohn AB, Uppsala, Sweden). Results were expressed as ${\mu}gEPX/mmol$ creatinine. Results : An early airway response after MCT was associated with an increase of U-EPX excretion for 0-3 hr after methacholine inhalation in comparison with beseline values. Most subjects showed a small increase in U-EPX excretion during late asthmatic response for 4-7 hr, which then decreased to normal level in 8-24 hr. Also, a tendency for a higher increase of U-EPX was associated with a lower threshold of methacholine challenge and a longer duration of asthma. Conclusion : Measurement of EPX in urine is a noninvasive and easy method to assess the severity of airway inflammation in asthmatic children. It may be a helpful index of the events underlying the airway inflammatory responses during nonspecific bronchial challenge, and in monitoring asthma management.

• Coupled systems mechanics
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• v.5 no.2
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• pp.157-190
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• 2016

This paper deals with frequency analysis of Euler-Bernoulli beams carrying an arbitrary number of Kelvin-Voigt viscoelastic dampers, subjected to harmonic loads. Multiple external/internal dampers occurring at the same position along the beam axis, modeling external damping devices and internal damping due to damage or imperfect connections, are considered. The challenge is to handle simultaneous discontinuities of the response, in particular bending-moment/rotation discontinuities at the location of external/internal rotational dampers, shear-force/deflection discontinuities at the location of external/internal translational dampers. Following a generalized function approach, the paper will show that exact closed-form expressions of the frequency response under point/polynomial loads can readily be derived, for any number of dampers. Also, the exact dynamic stiffness matrix and load vector of the beam will be built in a closed analytical form, to be used in a standard assemblage procedure for exact frequency response analysis of frames.

• Journal of Technology Innovation
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• v.25 no.4
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• pp.17-45
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• 2017

This article reviews studies on the societal challenge and technological innovation. Technological innovation in response to social problems is a relatively recent topic of Innovation Studies. Socially-oriented innovations and policies are different in terms of the goals, innovation processes, and ecosystems when compared with industrial innovation. This study examines the existing research that discusses science and technology innovation from the viewpoint of solving societal problems and discusses the direction of future research. This paper presents major research issues on the characteristics of innovation in societal problem solving, innovation governance, roles and ecosystem of innovators, and relationship between societal problem solving policies and other policies.

• Journal of Animal Science and Technology
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• v.55 no.4
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• pp.281-288
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• 2013

This experiment was conducted to determine the effects of extracts from fruit by-products on the blood characteristics, antioxidant activities, and immune response to Escherichia coli lipopolysaccharide (LPS) in growing pigs. A total of 96 pigs [(Landrace ${\times}$ Yorkshire) ${\times}$ Duroc] with an initial BW of $27.94{\pm}0.92kg$ were used in a 6-week feeding trial. The pigs were randomly placed into one of four treatment groups with six replications (four pigs per replication) per treatment according to their initial BW. Treatments were: 1) CON (basal diet), 2) PRO (CON + 0.5% procyanidin), 3) HES (CON + 0.5% hesperetin), 4) TAN (CON + 0.5% tannin). At the end of the sixth week, five pigs (total 20 pigs, $BW=27.94{\pm}0.92kg$) were selected from each treatment and injected with LPS ($100{\mu}g/kg$ of BW). Blood samples were collected 3 h after LPS injection to assess anti-oxidative and inflammatory responses. After the LPS challenge, the concentration of serum cholesterol decreased with fruit by-product treatment compared with CON (p<0.05). The administration of TAN increased the concentration of blood total protein compared with the CON group 3 h after LPS challenge (p<0.05). The albumin concentration was also higher with PRO treatment compared to HES treatment (p<0.05). The concentration of IgM was increased by fruit by-product supplementation at 0 and 3 h (p<0.05). In addition, IgG concentration was higher in PRO, HES, and TAN treatments compared to CON treatment at 0 h, and IgG concentrations were also higher in the HES group compared to the CON group at 3 h (p<0.05). The concentration of IgA also increased with fruit by-product treatments at 3 h (p<0.05). In conclusion, dietary supplementation with fruit by-products may moderate the immune response after a LPS challenge in growing pigs.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.379-384
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• 2003

Coal-burning utilities are facing a major NOx control compliance challenge due to the heavy emission regulation. In response to this challenge, some applicative technologies to effectively reduce NOx are developed and applied in the pulverized coal power plants. One of these is low NOx burner(LNB) equipped with multi-staged air register. In this study, NOx emission rate and flame shapes are investigated with secondary and tertiary air flow conditions in air staged coal burner, and the optimal windows of flow conditions to minimize NOx emission rate are found out. The test conditions treated in this study are the flow rate, swirl direction and intensity and throat injection velocity of secondary and tertiary air.

• Toxicological Research
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• v.22 no.4
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• pp.357-364
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• 2006

This study was undertaken to develop a reliable mice model demonstrating similar immunologic phenomena as human atopic dermatitis characterized with predominance of type-2 immune response. BALB/C mice and NC/Nga mice were sensitized twice with $100{\mu}l$ of 1% 2,4-dinitrochlorobenzene (DNCB) or vehicle (acetone : olive oil=4:1 mixture) in a week and challenged twice with $100{\mu}l$ of 0.2% DNCB or the vehicle at the following week. Mice were sacrificed at 19 days following the second DNCB or vehicle challenge for NC/Nga mice and at 28 days following the second DNCB or vehicle challenge for BALB/c mice. Upregulation of plasma 1gE, a hallmark of atopic dermatitis occurrence, was evident in the plasma obtained 4 day after the second DNCB challenge from BALB/c mice (approximately 4-fold) and NC/Nga mice (approximately 6-fold) treated with DNCB in comparison with that of the vehicle treated-control mice, and remain higher $3{\sim}4$ week after the second challenge. Ratio of plasma IgG1 versus IgG2a concentration was significantly higher in the mice treated with DNCB than the control mice, which also implies the skewed type-2 reactivity in vivo. Ratio of interleukin-4 versus interferon gamma produced in the splenic T cell culture supernatants was approximately 3-fold higher in the both strains of mice treated with DNCB than their control mice, respectively. The DNCB-treated mice demonstrated atopic dermatitis-like skin legions characterized with erythma, scaling, and hemorrhage, which was not observed with the control mice. Scratching on face or dorsal area was significantly more frequent (approximately 25-fold) in the DNCB-treated mice than the control at next day of the second DNCB challenge, and scratching frequency remains higher (approximately 4-fold) in the mice treated with DNCB than the control at 14 day following the second DNCB challenge. Overall, the mice model developed through sensitization and challenge with DNCB may be useful for research on atopic dermatitis and development of treatment materials for atopic dermatitis.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.7A
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• pp.717-723
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• 2007

There are many weaknesses in sensor networks due to hardware limitation of sensor nodes besides the vulnerabilities of a wireless channel. In order to provide sensor networks with security, we should find out the approaches different from ones in existing wireless networks; the security mechanism in sensor network should be light-weighted and not degrade network performance. Sowe proposed a novel data origin authentication satisfying both of being light-weighted and maintaining network performance by using Unique Random Sequence Code. This scheme uses a challenge-response authentication consisting of a query code and a response code. In this paper, we show how to make a Unique Random Sequence Code and how to use it for data origin authentication.