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Pilot-scale Applications of a Well-type Reactive Barrier using Autotrophic Sulfur-oxidizers for Nitrate Removal (독립영양 황탈질 미생물을 이용한 관정형 반응벽체의 현장적용성 연구)

  • Lee, Byung-Sun;Um, Jae-Yeon;Lee, Kyu-Yeon;Moon, Hee-Sun;Kim, Yang-Bin;Woo, Nam-C.;Lee, Jong-Min;Nam, Kyoung-Phile
    • Journal of Soil and Groundwater Environment
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    • v.14 no.3
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    • pp.40-46
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    • 2009
  • The applicability of a well-type autotrophic sulfur-oxidizing reactive barrier (L $\times$ W $\times$ D = $3m\;{\times}\;4\;m\;{\times}\;2\;m$) as a long-term treatment option for nitrate removal in groundwater was evaluated. Pilot-scale (L $\times$ W $\times$ D = $8m\;{\times}\;4\;m\;{\times}\;2\;m$) flow-tank experiments were conducted to examine remedial efficacy of the well-type reactive barrier. A total of 80 kg sulfur granules as an electron donor and Thiobacillus denitrificans as an active bacterial species were prepared. Thiobacillus denitrificans was successfully colonized on the surface of the sulfur granules and the microflora transformed nitrate with removal efficiency of ~12% (0.07 mM) for 11 days, ~24% (1.3 mM) for 18 days, ~45% (2.4 mM) for 32 days, and ~52% (2.8 mM) for 60 days. Sulfur granules attached to Thiobacillus denitrificans were used to construct the well-type reactive barrier comprising three discrete barriers installed at 1-m interval downstream. Average initial nitrate concentrations were 181 mg/L for the first 28 days and 281 mg/L for the next 14 days. For the 181 mg/L (2.9 mM) plume, nitrate concentrations decreased by ~2% (0.06 mM), ~9% (0.27 mM), and ~15% (0.44 mM) after $1^{st}$, $2^{nd}$, and $3^{rd}$ barriers, respectively. For the 281 mg/L (4.5 mM) plume, nitrate concentrations decreased by ~1% (0.02 mM), ~6% (0.27 mM), and ~8% (0.37 mM) after $1^{st}$, $2^{nd}$, and $3^{rd}$ barriers, respectively. Nitrate plume was flowed through the flow-tank for 49 days by supplying $1.24\;m^3/d$ of nitrate solution. During nitrate treatment, flow velocity (0.44 m/d), pH (6.7 to 8.3), and DO (0.9~2.8 mg/L) showed little variations. Incomplete destruction of nitrate plume was attributed to the lack of retention time, rarely transverse dispersion, and inhibiting the activity of denitrification enzymes caused by relatively high DO concentrations. For field applications, it should be considered increments of retention time, modification of well placements, and intrinsic DO concentration.

Inter-device Mutual authentication and Formal Verification in M2M Environment (M2M 환경에서 장치간 상호 인증 및 정형검증)

  • Bae, WooSik
    • Journal of Digital Convergence
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    • v.12 no.9
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    • pp.219-223
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    • 2014
  • In line with the advanced wireless communication technology, M2M (Machine-to-Machine) communication has drawn attention in industry. M2M communication features are installed and operated in the fields where human accessibility is highly limited such as disaster, safety, construction, health and welfare, climate, environment, logistics, culture, defense, medical care, agriculture and stockbreeding. In M2M communication, machine replaces people for automatic communication and countermeasures as part of unmanned information management and machine operation. Wireless M2M inter-device communication is likely to be exposed to intruders' attacks, causing security issues, which warrants proper security measures including cross-authentication of whether devices are legitimate. Therefore, research on multiple security protocols has been conducted. The present study applied SessionKey, HashFunction and Nonce to address security issues in M2M communication and proposed a safe protocol with reinforced security properties. Notably, unlike most previous studies arguing for the security of certain protocols based on mathematical theorem proving, the present study used the formal verification with Casper/FDR to prove the safety of the proposed protocol. In short, the proposed protocol was found to be safe and secure.

Effects of Salt Stress on Protein Content, ATPase and Peroxidase Activities in Tobacco. (염스트레스가 담배식물의 Protein, ATPase 및 Peroxidase 활성에 미치는 영향)

  • Lee, Sang-Gak;Kang, Byeung-Hoa;Lee, Hak-Su;Bae, Gill-Kwan
    • Korean Journal of Environmental Agriculture
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    • v.17 no.4
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    • pp.296-300
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    • 1998
  • The analysis of biochemical changes in tobacco plant as increase of NaCl concentraion was conducted. Total protein content and soluble protein content were decreased as NaCl concentration was increased, in that steady decreased until 120mM NaCl and largely decreased at 150mM NaCl. The expression of 74Kd subunit was increased until 60mM NaCl. However, the amount of 74Kd protein was decreased from 90mM NaCl. There was no difference for expression of other protein subunits. Chlorophyll a content was significantly decrease as NaCl concentration was increased, but chlorophyll b content was not much decreased. The slow increase up to 120mM NaCl and large increase at 150mM NaCl for ATPase and peroxidase activities indicated that 120mM NaCl could be a limiting concentration for salt injury.

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COLOCALIZATION OF LOCAL HOMOLOGY MODULES

  • Rezaei, Shahram
    • Bulletin of the Korean Mathematical Society
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    • v.57 no.1
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    • pp.167-177
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    • 2020
  • Let I be an ideal of Noetherian local ring (R, m) and M an artinian R-module. In this paper, we study colocalization of local homology modules. In fact we give Colocal-global Principle for the artinianness and minimaxness of local homology modules, which is a dual case of Local-global Principle for the finiteness of local cohomology modules. We define the representation dimension rI (M) of M and the artinianness dimension aI (M) of M relative to I by rI (M) = inf{i ∈ ℕ0 : HIi (M) is not representable}, and aI (M) = inf{i ∈ ℕ0 : HIi (M) is not artinian} and we will prove that i) aI (M) = rI (M) = inf{rIR𝖕 (𝖕M) : 𝖕 ∈ Spec(R)} ≥ inf{aIR𝖕 (𝖕M) : 𝖕 ∈ Spec(R)}, ii) inf{i ∈ ℕ0 : HIi (M) is not minimax} = inf{rIR𝖕 (𝖕M) : 𝖕 ∈ Spec(R) ∖ {𝔪}}. Also, we define the upper representation dimension RI (M) of M relative to I by RI (M) = sup{i ∈ ℕ0 : HIi (M) is not representable}, and we will show that i) sup{i ∈ ℕ0 : HIi (M) ≠ 0} = sup{i ∈ ℕ0 : HIi (M) is not artinian} = sup{RIR𝖕 (𝖕M) : 𝖕 ∈ Spec(R)}, ii) sup{i ∈ ℕ0 : HIi (M) is not finitely generated} = sup{i ∈ ℕ0 : HIi (M) is not minimax} = sup{RIR𝖕 (𝖕M) : 𝖕 ∈ Spec(R) ∖ {𝔪}}.

Mobility Management of M2M Devices with Grouping in the LTE System (LTE 시스템에서 그룹 기반 M2M 단말 이동성 관리)

  • Roh, Hee-Tae;Lee, Jang-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37B no.12
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    • pp.1119-1127
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    • 2012
  • The one of features of M2M communications, which are recently attracted attention as a future business of mobile communications, is that there is a large number of devices compared with traditional communication services. Hence, the control signal that are generated by the M2M devices may cause a significant congestion in the network and in order to solve this problem, a standardization is progressing for reducing the redundant signaling by managing M2M devices as a group in 3GPP standardization. In this paper, we propose a method of group based mobility management by managing M2M devices that have the same mobility as a group. In the proposed method, M2M devices that have the same mobility are grouped by the Mobility Management Entity (MME) and the MME elects a group header among the M2M devices in the group. Then, the group header performs the Tracking Area Update (TAU) on behalf of the group members to reduce the signaling overhead of mobility management. With the proposed method, we can achieve 80% decrease of the signaling overhead of mobility management compared with the case where each M2M device individually performs its TAU procedure.

A remote device authentication scheme in M2M communications (M2M 통신에서 원격장치 인증 기법)

  • Lee, Song-Hee;Park, Nam-Sup;Lee, Keun-Ho
    • Journal of Digital Convergence
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    • v.11 no.2
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    • pp.309-316
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    • 2013
  • Machine-to-machine (M2M) communication occurs when devices exchange information independent of human intervention. Prominent among the technical challenges to M2M communication are security issues, such as eavesdropping, spoofing, modification, and privacy violation. Hence, it is very important to establish secure communication. In this paper, we propose a remote authentication scheme, based on dynamic ID, which provides secure communication while avoiding exposure of data through authentication between the M2M domain and the network domain in the M2M architecture. We then prove the correctness and security of the proposed scheme using a logic-based formal method.

Effects of Polyamine on the Self-splicing Inhibition of Group I Intron by Spectinomycin (Polyamine이 Spectinomycin에 의한 Group I Intron의 Splicing 억제에 미치는 영향)

  • Park, In-Kook
    • Korean Journal of Microbiology
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    • v.35 no.4
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    • pp.253-257
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    • 1999
  • Effects of polyamines such as cadaverine, putrescine, spermidine and spermine on the self-splicig inhibition of the T4 phage thymidylate synthase(td) intron by spectinomycin have been investrigated. Without polyamine 7mM spectinomycin caused 40% reduction of the splicing rate. Cadaverine reduced the splicing rate over the concentrations of 0.1 to 5 mM. Putrescine at 0.5 mM increased the splicing rate by 13%. Spermidine at 0.5 mM enhanced the splicing rate by 11% while spermine at 0.01 mM enhanced the splicing rate by 16%. Of the all polyamines tested, spermine exhibited the maximum activation effect to counteract the splicing inhibition by spectinomycin. This effect appears to be due to the role of polyamine in stabilizing the conformation of td intron ribozyme essential for the catalytic function.

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Optimizing the Design of M2M Device and Methodology for Integrating 4M Manufacturing Resources (M2M Device최적화 설계와 4M 생산자원 정보통합)

  • Yoon, Jai-Young;Kim, Han-Gyu;Lee, Sung-Geun;Heo, Young-Sook;Cha, Suk-Keun
    • Journal of the Korean Society for Precision Engineering
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    • v.29 no.4
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    • pp.380-385
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    • 2012
  • This paper contains the optimized M2M technology, and the information of production resource of 4M, which understanding the roles and functions of M2M Device, and the explanation of its effectiveness, and the information of optimized M2M Device in IT convergence point of view. In addition, this content also points out the optimized M2M Device, analyzes and collects various type of management information which emphasizes the need for a common platform's were Middleware, and Auto-Configuration, WebLine Monitoring, WebService through the functionality of an integrated management information supports the productions by digitizing the information with standardized data for management efficiency.

GROUP-FREENESS AND CERTAIN AMALGAMATED FREENESS

  • Cho, Il-Woo
    • Journal of the Korean Mathematical Society
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    • v.45 no.3
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    • pp.597-609
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    • 2008
  • In this paper, we will consider certain amalgamated free product structure in crossed product algebras. Let M be a von Neumann algebra acting on a Hilbert space Hand G, a group and let ${\alpha}$ : G${\rightarrow}$ AutM be an action of G on M, where AutM is the group of all automorphisms on M. Then the crossed product $\mathbb{M}=M{\times}{\alpha}$ G of M and G with respect to ${\alpha}$ is a von Neumann algebra acting on $H{\bigotimes}{\iota}^2(G)$, generated by M and $(u_g)_g{\in}G$, where $u_g$ is the unitary representation of g on ${\iota}^2(G)$. We show that $M{\times}{\alpha}(G_1\;*\;G_2)=(M\;{\times}{\alpha}\;G_1)\;*_M\;(M\;{\times}{\alpha}\;G_2)$. We compute moments and cumulants of operators in $\mathbb{M}$. By doing that, we can verify that there is a close relation between Group Freeness and Amalgamated Freeness under the crossed product. As an application, we can show that if $F_N$ is the free group with N-generators, then the crossed product algebra $L_M(F_n){\equiv}M\;{\times}{\alpha}\;F_n$ satisfies that $$L_M(F_n)=L_M(F_{{\kappa}1})\;*_M\;L_M(F_{{\kappa}2})$$, whenerver $n={\kappa}_1+{\kappa}_2\;for\;n,\;{\kappa}_1,\;{\kappa}_2{\in}\mathbb{N}$.

Adaption and Assessment of ETSI M2M Standard in Smart Home Environments (ETSI M2M 표준의 스마트 홈 적용 및 적합성 평가)

  • Park, Yunjung;Wu, Hyuk;Paek, Hyung-Goo;Min, Dugki
    • Journal of Information Technology Services
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    • v.11 no.3
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    • pp.241-255
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    • 2012
  • Recently, smart home environments which provide complex services through smart appliances are becoming realized, due to the advances in connected devices and network technologies. Current smart home environments are mostly restricted, because of difficultly of integration of heterogeneous smart appliances. Therefore radical service integration is impracticable. In this paper, we analyze and implement Machine-to-Machine (M2M) standards which are established by European Telecommunications Standards Institute (ETSI) for integrating heterogeneous devices and services. Smart Home is one of the areas covered by ETSI M2M standards, however these standards are just standardized, so adaption and assessment in smart home are not proved yet. Therefore, this paper analyze ETSI M2M standards by focusing the data transport model and evaluate by selecting the most commonly used smart home scenarios and by implementing ETSI M2M standards compatible smart metering system. In some points ETSI M2M standards are not efficient because of its complexity of structure, however ETSI M2M provides sophisticated features for integrating M2M which are appropriate to adopt diverse smart home environments.