• Proceedings of the Korean Vacuum Society Conference
• /
• 2010.02a
• /
• pp.387-387
• /
• 2010

식품산업 및 가정의 주방에 이르기까지 다양한 분야에서 식품을 가공 조리하는 곳에는 보건 건강을 위하여 비닐장갑은 반드시 필요하다. 최근에는 다양한 소재를 이용하여 위생 비닐장갑을 개발을 하고 있으나 일회용성으로 저가의 물품으로 인식되어 생활에 중요성에 비해 개발이 미흡한 실정이다. 위생 비닐장갑은 다양한 산업에서 필수품으로 활용되고 있는 만큼 위생적이고 내구성이 높은 제품의 개발이 절실히 요구되는 실정이다. 이에 본 연구에서는 봉합면의 측면이 사용중 터지지 않도록 하기 위하여 봉합선의 폭을 기존의 0.1 mm 대신에 1 mm정도로 넓게 하는 기술과 무균성 위생 비닐장갑의 제조 공정 자동화에 주력함으로써, 고품위 무균성 위생비닐장갑을 열공정 안정화 자동화 공정으로 제작코자 하였다. 본 연구의 수행시 당면한 가장 큰 문제점은 봉합선의 폭이 넓어짐에 따라서 knife 형태를 갖는 가열된 금형의 칼날이 비닐과 접촉되어 실링을 하는 단계에서 금형에 비닐이 녹아서 붙어버리는 sticking 현상이 발생하였다. 이는 현장에서 심각한 문제로 더 이상 상용화가 불가능함을 의미한다. 이에 본 연구에서는 금형(die) 재료로 2가지의 서로 다른 소재를 선택해서 상온 상압플라즈마 처리를 함으로써 금형과 비닐사이에 발생하던 sticking 문제를 해결하고자 하였다. 금형으로 사용한 소재는 스테인리스(STS304)와 공구강(SCM)을 사용하였다. 두 시편에 대하여 상온상압 플라즈마 처리를 수행한 뒤 증류수와 Diiodomethane를 이용하여 접촉각과 표면에너지를 측정하였다. 상온 상압플라즈마 처리 시간은 0 ~ 9초로 하였다. 스테인리스의 경우 접촉각이 증류수를 이용하였을 때 $69.7^{\circ}$, $32.2^{\circ}$, $16.7^{\circ}$였으며 Diiodomethane을 이용하였을 때는 $37.3^{\circ}$, $17.6^{\circ}$, $10.6^{\circ}$였다. 표면에너지(surface energy)의 경우 48.13 mN/m, 72.06 mN/m, 78.66 mN/m로 플라즈마 처리시간이 길어질수록 표면 에너지 값이 증가하였다. 공구강의 경우는 증류수를 이용하였을 때 접촉각이 $70.2^{\circ}$, $36.8^{\circ}$, $28.9^{\circ}$였으며 Diiodomethane를 이용하였을 때는 $38.65^{\circ}$, $22.8^{\circ}$, $20.2^{\circ}$였다. 표면에너지의 경우 47.43 mN/m, 69 mN/m, 73.15 mN/m로 스테인리스와 같이 표면에너지 값이 커지는 것을 확인할 수 있었다. 학술대회에서는 금형의 표면에너지를 증기시키거나 감소시키는 방법에 대한 연구결과를 발표할 예정이다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.2
• /
• pp.285-292
• /
• 2009

In 2005, Lee and Chen suggested an enhanced one-time password authentication scheme which can prevent the stolen verifier attack that the Yeh-Shen-Whang's scheme has. The Lee-Chen's scheme addresses the stolen verifier attack by deriving each user's pre-shared secret SEED from the server secret. However, we investigated the weakness of the Lee-Chen's scheme and found out that it was suffering from the off-line dictionary attack on the server secret. We demonstrated that the off-line dictionary attack on the server secret can be easily tackled with only the help of the Hardware Security Modules (HSM). Moreover, we improved the scheme not to be weak to the denial of service attack and allow compromise of the past session keys even though the current password is stolen. Through the comparison between the Lee-Chen's scheme and the proposed one, we showed that the proposed one is stronger than other.

• Journal of Korean Biological Nursing Science
• /
• v.21 no.2
• /
• pp.133-140
• /
• 2019

Purpose: The purpose of this study was to check the degree of residual microbial contamination after disinfection of reusable suction containers, used in an intensive care unit (ICU) and present basic data for efficient use through cost analysis in comparison to disposable suction containers. Methods: This study was conducted on 32 reusable suction containers used in an ICU on a selected specific day. After disinfection and washing, specimens were collected from the used containers and cultured to check for microbial contamination. Additionally, a comparative narrative study analyzes the cost of using reusable suction containers and disposable suction containers. Data were analyzed with the SPSS WIN 20.0 program using real numbers and percentage ${\chi}^2$-test. Results: As a result of the study, microorganisms were found in all samples where in 30 were gram-positive (62.5%) while 13 were gram-negative (27.1%). Based on level of contamination, microorganisms were less than 10CFU/ml in 18 samples (56.3%); 11-99CFU/ml in six samples (18.8%); and more than 100CFU/ml in eight samples (25%). Cost per day for a reusable suction container was $10,655+{\alpha}$ while cost per day for a disposable suction container was 10,666 won. Conclusion: This study found that reusable suction containers, even after disinfection, accounted for factors of potential infection as well as microbial contamination. So, disposable suction containers are superior in cost-effectiveness and highly efficient for use with infected patients.

• Smart Media Journal
• /
• v.10 no.3
• /
• pp.48-53
• /
• 2021

The authentication process is a key step that should be used to verify that a user is legitimate, and it should be used to verify that a user is a legitimate user and grant access only to that user. Recently, two-factor authentication and OTP schemes are used by most applications to add a layer of security to the login process and to address the vulnerability of using only one factor for authentication, but this method also allows access to user accounts without permission. This is a known security vulnerability. In this paper, we propose a Zero Knowledge Proofs (ZKP) personal information authentication scheme based on a Smart Contract of a block chain that authenticates users with minimal personal information exposure conditions. This has the advantage of providing many security technologies to the authentication process based on blockchain technology, and that personal information authentication can be performed more safely than the existing authentication method.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.22 no.6
• /
• pp.1271-1282
• /
• 2012

Recently, security incidents occur continuously, resulting in the leakages of a large amount of the company's confidential and private information. For these reasons, the security technologies such as the authentication and the access control in order to prevent the information leakage are attracting attention. In particular, location-based authentication that utilizes the user's current location information which is used an authentication factor. And it provides more powerful authentication by controlling the users who attempt to access and blocks internal information leakage path. However, location information must be handled safely since it is the personal information. The location based authentication scheme proposed in this paper enhances the stability of the process location information compared with existing relevant location-based authentication protocol. Also it strengthens the end-user authentication by using one-time password. In addition, the proposed scheme provides authentication to prevent information leakage and employs the concept of the user's physical access control. Resultingly, the proposed scheme can provide higher security than the previous studies, while guarantee to low communication cost.

• Journal of IKEEE
• /
• v.25 no.4
• /
• pp.607-612
• /
• 2021

This paper presents a novel CPW-fed UWB monopole paper antenna made by paper and copper tape. Through the simulation, the optimized antenna design parameters were obtained, and an antenna having an omni-directional radiation pattern and a gain of 2.2 dBi or more in the UWB frequency band of 3.1-10.6 GHz was designed. The antenna was manufactured using general A4 paper and copper tape, and the measurement result satisfies the return loss of -10dB or less in the UWB frequency band and confirm that the return loss characteristic was maintained even when the antenna plane was bent by 3 mm in the longitudinal direction. The proposed antenna is a wearable device that can provide services in the UWB band, and can be manufactured inexpensively by printing it with a conductive print on paper. So it can be used as a wearable antenna for UWB communication in various application fields such as logistics and disposable terminals.

• The Journal of the Acoustical Society of Korea
• /
• v.41 no.4
• /
• pp.461-467
• /
• 2022

Sonobuoy is a disposable device that collects underwater acoustic information and is designed to transmit signals collected in a particular area to nearby aircraft or ships and sink to the seabed upon completion of its mission. In a conventional sonobouy signal transmission and reception system, collected signals are modulated and transmitted using techniques such as frequency division modulation or Gaussian frequency shift keying, and received and demodulated by an aircraft or a ship. However, this method has the disadvantage of the large amount of information to be transmitted and low security due to relatively simple modulation and demodulation methods. Therefore, in this paper, we propose a method that uses an autoencoder to encode a transmission signal into a low-dimensional latent vector to transmit the latent vector to an aircraft or ship and decode the received latent vector to improve signal security and to reduce the amount of transmission information by approximately a factor of a hundred compared to the conventional method. As a result of confirming the sample spectrogram reconstructed by the proposed method through simulation, it was confirmed that the original signal could be restored from a low-dimensional latent vector.

• Journal of Biomedical Engineering Research
• /
• v.44 no.1
• /
• pp.1-10
• /
• 2023

With the announcement of MEDICAL DEVICE REGULATION 2017/745 (MDR) on April 5 2017, medical device manufacturers shall apply ISO 14971:2019 (3^rd) revised in December 2019. However, there is not much related information and guidance available to medical device manufacturers, especially single use medical device. Risk management process basically follow 5 steps which are Risk Analysis, Risk Evaluation, Risk Control, Evaluation of overall residual risk and post-production activities. The purpose of this study is to provide a guidance of from risk analysis with Failure Mode and Effects Analysis (FMEA) table to overall residual risk evaluation for the single use medical device and to reflect it in a Periodic Safety Update Reports (PSUR) to satisfy with MDR requirements with single use medical device which are widely used and manufactured FDA class 2 or CE class IIb as examples. For this study, single use medical device manufacturer can adopt ISO 14971:2019 in accordance with MDR requirements and it can be extended to the PSUR. But there are still limitations to adopt to the all-single use medical device especially high class, private device and implantable device. So, Competent Authority (CA) shall publish more guidance for the single use medical device.

• Journal of Korean Clinical Nursing Research
• /
• v.28 no.1
• /
• pp.76-87
• /
• 2022

Purpose: The purpose of this study was to examine the psychological distress related to quality of life (QoL) of patients with colorectal cancer receiving 5-fluorouracil (5-FU) chemotherapy at home with disposable Elastomeric infusion pumps. Methods: In this study, 179 colorectal outpatients were recruited between September 2019 and January 2021. National Cancer Center Psychological Symptom Inventory scores, general self-efficacy, and the EORTC QLQ-C30 scores were measured. Data were analyzed using Independent t-test, One-way ANOVA with Bonferroni post hoc analysis, and hierarchical multiple linear regression with the SPSS/WIN 26.0 programs. Results: The overall prevalence of psychological distress was 52.0% in colorectal patients. In multiple regression, psychological distress (β=-.20, p=.005), appetite loss (β=-.20, p=.001), chemotherapy cycles (β= .19, p=.002), fatigue (β=-.16, p=.035), physical functioning (β=-.16, p=.024), and emotional functioning (β=-.15, p=.025) were significant factors of QoL, and the final model explained 45.0% of the total variance of QoL. Conclusion: Supporting patients toward decreased psychological distress and increased physical and emotional functioning, especially in the first or second cycle of chemotherapy, could be used to improve their QoL. To consider the thresholds for clinical importance, it is necessary to increase the interpretation of psychological distress in clinical practice and further research.

• Applied Chemistry
• /
• v.15 no.1
• /
• pp.17-20
• /
• 2011

A disposable light exposure detector kit has been developed by UV curing of a hydrogel material. The devised light exposure detector kit consisted of light sensitive structures, bottom plate, character sheet and sticky back plate. A light exposure detector kit has a serial light sensitive structures that contain various light sensitive dyes such as rhodamine and fluorescein. The light sensitive structure composed of UV curable hydrogel polymer material as a supporing material and photosensitive dye in a certain concentration. The fabrication procedure of the ligh exposure detector kit is very simple and fast due to UV curing procedure of a photopolymerizable hydrogel material such as poly(ethylene glycol) methyl ether acrylate (PEGMEA) and poly(ethylene glycol) diacrylate (PEGDA) with a photosensitive dye. By the proposed fabrication method, various size and shape of a light exposure detector kit could be fabricated using a flexible elastomer mold. Due to a fast and inexpensive fabrication method, the light exposure detector kit could be use a single use for various industrial applications. According to light irradation, the light sensitive structure on a light exposure detector kit could be lose its color by decomposition of a photosensitive dye chemical in the structure. Thus the amount of the exposed light on a substrate could easily be recognised by changing color or transparency of the structure.