• Journal of Science and Technology Studies
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• v.2 no.2 s.4
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• pp.25-54
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• 2002

Without much communication, large-scale surveys of public knowledge of, and attitudes to, science (quantitative PUS) and case-study analyses of the public's understandings of science in particular (constructivist PUS) have dominated in the public understanding of science (PUS) area. Not only methodological preference but also a strong antipathy against value-orientations that each approach presumed to have and support has been barriers for quantitative PUS and constructivist PUS to benefit each other. In order to overcome such barriers, this paper demonstrates that value orientations guiding quantitative PUS have been much more diverse than what constructivist PUS researchers might think, and that quantitative PUS has indeed yielded the results consistent with and complementary to constructivist PUS. Finally this paper proposes that (1)quantitative PUS should test propositions provided by constructivist PUS, so that it can contribute much to the construction of more generalizable PUS theories and policies, and (2)constructivist PUS uses the outcome of quantitative PUS to develop more complex case studies which consider heterogeneous publics, trends of public evaluations of science, and how public attitudes to science in the abstract and public attitudes to science in particular in a specific context have effect on each other.

• Elastomers and Composites
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• v.58 no.2
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• pp.70-80
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• 2023

The effect of phenylphosphonic acid (PPOA) on polyurethane (PU) thermal stability was studied through Fourier transform infrared spectroscopy and Thermogravimetric analysis. To synthesize PPOA-modified PUs (PPOA-PUs), polyether-type diols (Mw=62, 106, 190, 419, 605) were chemically modified with PPOA and then reacted with 4,4'-dicyclohexylmethane diisocyanate (H₁₂MDI) and 4,4-diphenylmethane diisocyanate (MDI). During thermal decomposition in air, the PPOA embedded in the PUs formed intumescent phosphocarbonaceous char. Below 400℃, PPOA-H₁₂MDI-PUs were more unstable, as PPOA decomposed at lower temperatures than phenyl groups and aliphatic ethers. Above 550℃, the thermal stability of PUs followed this order: PPOA-MDI-PUs > PPOA-H₁₂MDI-PUs > MDI-PUs > H₁₂MDI-PUs. At 700℃, unmodified PUs had no residue, while the PPOA-MDI-PU residue was 4.4~23.0 wt.% and the PPOA-H₁₂MDI-PU residue was 1.5~17.5 wt.%. The enhanced thermal stability of PPOA-MDI-PUs at high temperatures can be attributed to the synergetic effect of PPOA and phenyl groups on the formation of phosphocarbonaceous char.

• Journal of Science and Technology Studies
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• v.2 no.2 s.4
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• pp.1-23
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• 2002

This Article examines the main approaches to the public understanding of science(PUS) in light of the changing relation of science and public. Traditional approach called deficit model recognizes scientific knowledge as a entity, unidirectionally diffusing to public. This View basically presupposes the gap between science and public. Meanwhile, this approach has an aspiration to reduce the gap. So there is a paradoxical situation in the traditional PUS. Public perception of environmental crisis and risk of science has been risen since late 1980's. And the science technology studies (STS) have criticized traditional approach. STS proposes new approach of constructive PUS. Constructive PUS conceives the public to have heterogeneous, local characteristic. This approach has been very fertile both in theory and practice. But most recently, newly proposed approach, so called heterogeneous PUS, criticizes constructive PUS. Main point of criticism is that constructive PUS has dichotomy between science and public, and romanticizes the public. It is uncertain whether heterogeneous PUS can take place of constructive PUS. But this trend has the implication that the relation of science and public is constantly changing.

• The Journal of the Korean dental association
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• v.9 no.12
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• pp.841-845
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• 1971

Author has made the studies on the pH of pus in the 53 suppurative disesed patients who had admitted to department of ora surgery, Infirmary of Schoo of Dentistry, Seoul National University. The results were obtained as follows; 1. The average pH of pus in the patients with suppurative oral diseases was 6.46 and the pH of pus was ranging 5.0 to 7.2. 2. The pH value of pus was not significant between the males(pH: 6.58) and females (pH: 6.40). 3. The pH vaule of pus in patients treated by antibiotics trend to slightly alkaline than that of untreated patients. 4.The pH vaule of pus in the pericoronitis, periodontal abscess and other localized oral infections were slightly alkaline than buccal abscess and osteomyelitis, and acute suppurative diseases of jaws was more acid than chronic diseases. In general, it was seemed the early stages of inflammation was alkaline, and the later stages was acid.

• Journal of Korea Technology Innovation Society
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• v.6 no.2
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• pp.137-158
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• 2003

This paper examines theoretical trends and policy issues concerning science and public. The dominant perspective about it was changed from “popularization of science” to “public understanding of science (PUS)”. PUS pays attention to active roles of public in the understanding of science based on the contextual model. And recently various concepts are attempted to complement PUS such as “heterogeneous PUS”, “quantitative PUS”, “public understanding of research”, and “public participation in science”. PUS related activities in Korea can be analyzed using the concept of “science and technology culture system”. The characteristics of science and technology culture system in Korea can be summarized as follows: Its purpose is confined to support existing national innovation system; Its constituents have been unevenly and separately developed; Its material and institutional infrastructure is not sufficiently prepared; Its organizing mechanism is strongly influenced by government's execution power.

• Journal of Navigation and Port Research
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• v.35 no.2
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• pp.121-130
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• 2011

The localization of vehicle is an important part of an unmanned vehicle control problem. Pseudolite ultrasonic system(PUS) is the method to find an absolute position with a high accuracy by using ultrasonic sensor. And Gyro is the inertial sensor to measure yaw angle of vehicle. PUS can be able to estimate the position of mobile robot precisely, in which errors are not accumulated. And Gyro is a more faster measure method than PUS. In this paper, we suggest a more accuracy method of calculating PUS which is numerical analysis approach named Newtonian method. And also propose the fusion method to increase the accuracy of estimated angle on moving vehicle by using PUS and Gyro integrated system by Kalman filtering. To control the 4WS unmanned vehicle, the trajectory following algorithm is suggested. And the new concept arbitration of goal controller is suggested. This method considers the desirability function of vehicle state. Finally, the performances of Newtonian method and designed controller were verified from the experimental results with the 4WS vehicle scaled 1/10.

• Aerospace Engineering and Technology
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• v.6 no.1
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• pp.92-96
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• 2007

The conventional commands & telemetry system of Korean low-earth orbiting satellites has certain limitations in accommodating various missions. As the payload becomes complex, it requires very complicated operational concepts in terms of commands and telemetry. With the current design, commands and telemetry formats have to be rebuilt whenever new payloads or operation concepts are involved, and many constraints in operation shall be produced due to the lacks of its flexibility. In this paper, a new strategy for commands & telemetry development partially derived from PUS (Packet Utilization Standard) of European Space Agency, which provides enhanced features for the accommodation of payloads & operational requirements, is presented.

• The Journal of the Korea Contents Association
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• v.16 no.2
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• pp.117-128
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• 2016

The growing socio-economic effect caused by science and technology requires public to participate in policy-making process, which makes government to boost public understanding of science(PUS). Government has also exerted to construct infra for PUS. However results are not so meaningful. The government-funded science museum has mainly provided the program for students. Besides, science broadcasting channel has recorded the worst viewing rate. Meanwhile, some of the private sector-manufactured contents have attracted public attention in recent years, which is realized by considering elements such as an interesting topic selection, use of outside experts, two-way communication system, level adjusting for public through flexible running system. This study analyze podcast based program, face to face lectures, display contents by private industry, fab lab etc. on the base of the reciprocal PUS model to sort out the reason they have successful results. Futhermore, it argues that government should intensify support for private sector and create synergy effect by cultivate collaboration system between government and private sector to enhance the efficiency of PUS and offers public policy to realize the plan.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.7
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• pp.2212-2230
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• 2014

Cognitive radio (CR) users, known as secondary users (SUs), should avoid interference with primary users (PUs) who own the licensed band, while trying to access it; when the licensed band is unused by the PUs. To detect PUs, spectrum sensing should be performed over in-band channels that are currently in use by SUs. If PUs return to access the band, SUs need to vacate it, disrupting the SUs' communication unless a non-utilized band is discovered. Obtaining a non-utilized band in a short period facilitate seamless communication for SUs and avoid interference on PUs by vacating from the channel immediately. Searching for a non-utilized band can be done through proactive out-of-band (OB) sensing. In this paper, we suggest a proactive OB sensing scheme that minimizes the time required to discover a non-utilized spectrum in order to continue communication. Although, the duration spent on OB sensing reduces the throughput of the CR networks that can be achieved on band being utilized, the lost throughput can be compensated in the new discovered band. We demonstrate that, the effect of our proposed scheme on the throughput owing to OB sensing is insignificant, while exhibiting a very short channel discovery time.

• Journal of Communications and Networks
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• v.17 no.4
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• pp.440-448
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• 2015

In this paper, we study the problem of selfish behavior of secondary users (SUs) based on cognitive radio (CR) with the presence of primary users (PUs). SUs are assumed to contend on a channel using the carrier sense multiple access with collision avoidance (CSMA/CA) and PUs do not consider transmission of SUs, where CSMA/CA protocols rely on the random deference of packets. SUs are vulnerable to selfish attacks by which selfish users could pick short random deference to obtain a larger share of the available bandwidth at the expense of other SUs. In this paper, game theory is used to study the systematic cheating of SUs in the presence of PUs in multichannel CR networks. We study two cases: A single cheater and multiple cheaters acting without any restraint. We identify the Pareto-optimal point of operation of a network with multiple cheaters and also derive the Nash equilibrium of the network. We use cooperative game theory to drive the Pareto optimality of selfish SUs without interfering with the activity of PUs. We show the influence of the activity of PUs in the equilibrium of the whole network.