• Journal of the Society of Naval Architects of Korea
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• v.43 no.6 s.150
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• pp.693-699
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• 2006

This paper proposes a design optimization technique for ship RCS signature reductions using Taguchi method. The proposed technique comprises of i)evaluating initial RCS signatures, ii)defining critical areas which should be modified as design parameters, and threat factors which can't be controlled artificially as noise parameters, and finally iv)finding optimum parameters via analyzing signal to noise ratios for designated characteristics. We applied the technique to a model ship and found that it is suitable for radar stealth designs. In addition, the proposed technique is applicable to submarine designs against sonar threats.

• Management & Information Systems Review
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• v.6
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• pp.1-19
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• 2001

Partial transactions which use computer networks are formed in the cyberspace due to rapid progress of communication and computer technology. Electronic business transactions have security problems according to the special quality of opening networks, while it can be approached easily by anyone without being tied to time and places through Internets. To revitalize the electronic business transactions, security technology which can establish its security and trust is the prior task and both safe information communication and better information security service offer are essential factors. The method to exchange information through Internets must be made after confirming one another's exact connection in the mutual identity certification to prevent a lot of threat which can occur in the use of password techniques. To satisfy these electronic business transactions, we intend to increase understanding of authentication algorithm provided with authentication function of messages and users as well to plan safety and trust of business information and contents in the electronic business transactions.

• Structural Engineering and Mechanics
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• v.32 no.2
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• pp.269-282
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• 2009

Responding to the threat of terrorist attacks around the world, numerous studies have been conducted to search for new methods of vulnerability assessment and protective technologies for critical infrastructure under extreme bomb blasts or high velocity impacts. In this paper, a two-dimensional behavioral rate dependent lattice model (RDLM) capable of analyzing reinforced concrete members subjected to blast and impact loading is presented. The model inherently takes into account several major influencing factors: the progressive cracking of concrete in tension, the inelastic response in compression, the yielding of reinforcing steel, and strain rate sensitivity of both concrete and steel. A computer code using the explicit algorithm was developed based on the proposed lattice model. The explicit code along with the proposed numerical model was validated using experimental test results from the Woomera blast trial.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.21 no.3
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• pp.15-20
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• 2013

Pilots' fatigue is one of the most serious threat to flying safety. Fatigue is influenced by many factors like sleep deprivation, daily activities, aging, stress, etc. This study was designed to investigate military pilots' daily activities. 20 pilots' daily activity was monitored by activity monitor, Fitbit(R), and the survey about sleep time and flight time was conducted. They placed Fitbit(R) on their waist for 5 days. During flight, they removed Fitbit(R) that had been used for checking their steps and walking distances. It was found that the average sleep time is 6.7 hours for fighter pilots. It was a little shorter than average sleep time for adults, 8 hours. Average steps per day was 6,838 which is more than sedentary worker's but less than active worker's. Their daily activities were not as high as we had expected. But their sleep time was very short. Flight surgeons should recommend them to take a rest and get sleep during rest period.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1252-1254
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• 2003

Debris flows associated with landslides occur as one of the most devastating natural disasters that threat Taiwan. Typically, three essential factors are needed simultaneously to trigger debris flow, namely sufficient soils and rocks, favorable slope, and abundant water. Among the three essentials, the slope is natural and static without external forcing, while the landslide is generally induced by earthquake or rainfall events, and the water is produced by heavy rainfall events. In this study, we analyzed the landslides triggered by the typhoons Herb (1996) and typhoon Troaji (2001). It is concluded that the statistical data are useful to quantify the threshold of the potential landslide area. Then, the possibility to prevent the debris flow occurrence may be increased.

• The Korean Nurse
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• v.37 no.2
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• pp.87-92
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• 1998

Immdeiate hypersensitivity reactions to natural rubber and latex products pose a significant threat to patients, healthcare workers, and the general population. The purpose of this study is to summarize the clinical syomptoms of latex rubber allergy and provide guidelines for the management of latex allergy. Contact dermatitis from the nearly constant use of latex gloves during the workday has become a real problem for many health care professionals. Moreover, the patient who come in contact with these gloves or with other latex-containing equipment may show reactons. Far worse than skin problems is life-threatening anaphyaxis, which can be the first indication that a person has latex sensitivity. In conclusion, nurses shold know the latex precautions such as risk factors, adverse reactons to latex, emergent treatment and so on.

• The Korean journal of internal medicine
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• v.33 no.6
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• pp.1070-1078
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• 2018

Vibrio vulnificus is a gram-negative bacterium that can cause serious, potentially fatal infections. V. vulnificus causes three distinct syndromes: an overwhelming primary septicemia caused by consuming contaminated seafood, wound infections acquired when an open wound is exposed to contaminated warm seawater, and gastrointestinal tract-limited infections. Case-fatality rates are higher than 50% for primary septicemia, and death typically occurs within 72 hours of hospitalization. Risk factors for V. vulnificus infection include chronic liver disease, alcoholism, and hematological disorders. When V. vulnificus infection is suspected, appropriate antibiotic treatment and surgical interventions should be performed immediately. Third-generation cephalosporin with doxycycline, or quinolone with or without third-generation cephalosporin, may be potential treatment options for patients with V. vulnificus infection.

• International Journal of Oral Biology
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• v.47 no.2
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• pp.17-24
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• 2022

Preserving intact genetic material and delivering it to the next generation are the most significant tasks of living organisms. The integrity of DNA sequences is under constant threat from endogenous and exogenous factors. The accumulation of damaged or incompletely-repaired DNA can cause serious problems in cells, including cell death or cancer development. Various DNA damage detection systems and repair mechanisms have evolved at the cellular level. Although the mechanisms of these responses have been extensively studied, the global RNA expression profiles associated with genomic instability are not well-known. To detect global gene expression changes under different DNA damage and hypoxic conditions, we performed RNA-seq after treating human cervical cancer cells with ionizing radiation (IR), hydroxyurea, mitomycin C (MMC), or 1% O₂ (hypoxia). Results showed that the expression of 184-1037 genes was altered by each stimulus. We found that the expression of 51 genes changed under IR, MMC, and hypoxia. These findings revealed damage-specific genes that varied differently according to each stimulus and common genes that are universally altered in genetic instability.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.29 no.2
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• pp.111-116
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• 2021

Normal Operation Safety Survey (NOSS) is a safety management tool used by air traffic control organizations to measure data related to threats and errors to proactively prevent accidents before they occur. NOSS was developed to be applied to the air traffic control field according to the concept of Line Operation Safety Audit (LOSA) conducted by airlines to reduce human errors in the cockpits. Safety management based on data is crucial for the prevention of control-related accidents, and the competency of observers for this is important for the successful implementation of NOSS. Based on LOSA implementation experiences and expert interviews, this paper introduces the international NOSS methods and discusses the key factors required for effective observation and the implementation methods and implications of NOSS observer training.

• International Journal of Computer Science & Network Security
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• v.22 no.12
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• pp.29-36
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• 2022

Smart grid (SG) software platforms and communication networks that run and manage the entire grid are increasingly concerned about cyber security. Characteristics of the smart grid networks, including heterogeneity, time restrictions, bandwidth, scalability, and other factors make it difficult to secure. The age-old strategy of "building bigger walls" is no longer sufficient given the rise in the quantity and size of cyberattacks as well as the sophisticated methods threat actor uses to hide their actions. Cyber security experts utilize technologies and procedures to defend IT systems and data from intruders. The primary objective of every organization's cybersecurity team is to safeguard data and information technology (IT) infrastructure. Consequently, further research is required to create guidelines and methods that are compatible with smart grid security. In this study, we have discussed objectives of of smart grid security, challenges of smart grid security, defensive cybersecurity techniques, offensive cybersecurity techniques and open research challenges of cybersecurity.