• Journal of Advanced Navigation Technology
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• v.15 no.5
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• pp.865-870
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• 2011

MD-64 is a 64-bit block cipher suitable for the efficient implementation in hardware environments such as WSN. In this paper, we propose a related-key amplified boomerang attack on the full-round MD-64. The attack on the full-round MD-64 requires $2^{45.5}$ related-key chosen plaintexts and $2^{95}$ MD-64 encryptions. This work is the first known cryptanalytic result on MD-64.

• Membrane Journal
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• v.7 no.2
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• pp.57-64
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• 1997

Membrane Distillation(MD) is reviewed as an application to new separation technology. Hydrophobic membrane which has been used to microfiltration is feasible material for MD process. MD has perfect selectivity under moderate temperature and is promised to simplify typical water treatment process. The principle of MD separation is phase transition by vapor-liquid interface at the pore of membrane surface. Feed and permeate temperature, composition, membrane wetting, heat and mass transfer phenomena affect the selectivity and flux of MD.

• International Journal of Internet, Broadcasting and Communication
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• v.11 no.3
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• pp.41-48
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• 2019

The Management Discussion and Analysis(MD&A) provides investors with an opportunity to gain insight into the company from a manager's perspective and enables short-term and long-term analysis of the business. And MD&A is an important channel through which companies and investors can communicate, providing a useful source of information for analyzing financialstatements. MD&A is measured by the quality of disclosure and there are many previous studies on the usefulness of disclosure information. Therefore, it is very important for the financial analyst who is the representative information user group in the capital market that MD&A Disclosure Quality is measured in real-time in combination with IT information technology and provided timely to financial analyst. In this study, we propose a method that real-time data is converted to digitalized data by combining MD&A disclosure with IT information technology and provided to financial analyst's information environment in real-time. The real-time information provided by MD&A can help the financial analysts' activities and reduce information asymmetry.

• Journal of Korean Society for Quality Management
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• v.50 no.4
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• pp.735-749
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• 2022

Purpose: The purpose of this study is to investigate whether the Management Discussion and Analysis (MD&A) has an impact on auditors' audit efforts. MD&A is a means of disclosure that provides information about a company from the management's perspective in financial reporting. The MD&A is a standardized format of nonfinancial information that can be useful for the stake-holders. The auditors have incentives to utilize the nonfinancial information contained in the MD&A for their decision-making. We posit that the MD&A disclosure quality is associated with the level of audit efforts. Methods: We hand-collect the disclosure data from the Financial Supervisory Service of Korea (the Korean SEC). Results: By employing two measures of audit efforts, we document evidence that the quality of MD&A is associated with both audit hours and audit fees. Conclusion: It implies that the auditors perform intensive audit work for companies with high-quality disclosure of MD&A. The study contributes to the literature by providing the first approach to examine the association between the MD&A disclosure and audit efforts.

• The korean journal of orthodontics
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• v.41 no.3
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• pp.184-190
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• 2011

Objective: The purpose of this study was to investigate the relationship between the enamel thickness of proximal surfaces and the morphologic features of mandibular incisors. Methods: Mesiodistal/faciolingual (MD/FL) index, MD width, and height of contour width/cervical width ratio were measured in 40 incisors extracted from Koreans. For determining the height of contour width/cervical width ratio, the cervical width was measured as the distance between proximal cementoenamel junctions. Then, the labial surface was ground to the height of the contour level to measure enamel thickness. Pearson correlation analysis was used to investigate the correlation between enamel thickness and morphologic features. Results: Enamel thickness was $0.75{\pm}0.07mm$ per side, and MD width was $5.56{\pm}0.40mm$. Enamel thickness and MD width were significantly correlated. However, a significant relationship was not observed between enamel thickness and MD/FL index or the height of contour width/cervical width ratio. Conclusions: The results suggest that enamel thickness is affected only by MD width. Therefore, if the MD width is the same for mandibular incisors with a large MD/FL index or triangular shape and mandibular incisors with normal shape, then the limit of enamel reduction for reproximation will be the same.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.2
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• pp.63-74
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• 2009

In 2005, Wang et al. discovered devastating collision attacks on the main hash functions from the MD4 family. After the discovery of Wang, many analysis results on the security of existing hash-based cryptographic schemes are presented. At CRYPTO'07, Fouque, Leurent and Nguyen presented full key-recovery attacks on HMAC/NMAC-MD4 and NMAC-MD5[4]. Such attacks are based on collision attacks on the underlying hash function, and the most expensive stage is the recovery of the outer key. At EUROCRYPT'08, Wang, Ohta and Kunihiro presented improved outer key recovery attack on HMAC/NMAC-MD4, by using a new near collision path with a high probability[2]. This improves the complexity of the full key-recovery attack on HMAC/NMAC-MD4 which proposed by Fouque, Leurent and Nguyen at CRYPTO'07: The MAC queries decreases from $2^{88}$ to $2^{72}$, and the number of MD4 computations decreases from $2^{95}$ to $2^{77}$. In this paper, we propose improved outer key-recovery attack on HMAC/NMAC-MD4 with $2^{77.1246}$ MAC queries and $2^{37}$ MD4 computations, by using divide and conquer paradigm.

• Journal of Korea Multimedia Society
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• v.12 no.1
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• pp.1-15
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• 2009

This paper presents an assignment method of the multidimensional type inheritance indexes (MD-TIXs) to support the processing of XML queries in XML databases. MD-TIX uses a multidimensional index structure for efficiently supporting nested predicates that involve both nested element and type inheritance hierarchies. In this paper, we have analyzed the strategy of the query processing by using the MD-TIXs, and presented an assignment method of the MD-TIXs in the framework of complex queries, containing conjunctions of nested predicates, each one involving an Xpath having target types or domain types substitution. We first consider MD-TIX operations caused by updating of XML data-bases, and the use of the MD-TIXs in the case of a query containing a single nested predicate. And then, we consider the assignments of the MD-TIXs in the framework of more general queries containing nested predicates over overlapping paths that have common subpaths.

• Journal of the Korean Mathematical Society
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• v.46 no.6
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• pp.1179-1192
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• 2009

In this note we give a new generalization of the notions of $Pr{\ddot{U}}fer$ domain and PvMD which uses quasi semistar invertibility, the "quasi P$\star$MD", and compare them with the P$\star$MD. We show in particular that the problem of when a quasi P$\star$MD is a P$\star$MD is strictly related to the problem of the descent to subrings of the P$\star$MD property and we give necessary and sufficient conditions.

• The Journal of Engineering Geology
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• v.11 no.3
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• pp.269-278
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• 2001

We describe the calculation of thermal expansion coefficients of $\alpha$-quartz, muscovite and albite using a MD simulation method. The selection of interatomic potentials is important for the MD calculation, and we used the 2-body interatomic potential function. The coefficients are calculated using a differential operation of the temperature dependence of the lattice constant obtained from the NPT-ensemble molecular dynamics simulation. Reasonable agreement is found between the analytical results and measured data.

• Journal of Information Technology Services
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• v.22 no.4
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• pp.21-35
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• 2023

Software as Medical Devices (SaMD) is a growing category of medical devices that are composed of software to perform one or more medical purposes. SaMD is less likely to cause physical harm compared to conventional medical devices, particularly medical electrical equipments, and may be more vulnerable to privacy issues. This difference was acknowledged and resulted in introducing new regulation guidance specifically for cybersecurity of SaMD. It guides stakeholders of SaMD what to consider in what context in terms of cybersecurity. This study examines the current guidance of how cybersecurity is considered for SaMD by analyzing current medical device standards, then suggest which concept or details beyond current medical device standards may be applicable through analysis of international standards documents published for software in general.