• Title/Summary/Keyword: acyclic

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Semantic-based Automatic Open API Composition Algorithm for Easier-to-use Mashups (Easier-to-use 매쉬업을 위한 시맨틱 기반 자동 Open API 조합 알고리즘)

  • Lee, Yong Ju
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.5
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    • pp.359-368
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    • 2013
  • Mashup is a web application that combines several different sources to create new services using Open APIs(Application Program Interfaces). Although the mashup has become very popular over the last few years, there are several challenging issues when combining a large number of APIs into the mashup, especially when composite APIs are manually integrated by mashup developers. This paper proposes a novel algorithm for automatic Open API composition. The proposed algorithm consists of constructing an operation connecting graph and searching composition candidates. We construct an operation connecting graph which is based on the semantic similarity between the inputs and the outputs of Open APIs. We generate directed acyclic graphs (DAGs) that can produce the output satisfying the desired goal. In order to produce the DAGs efficiently, we rapidly filter out APIs that are not useful for the composition. The algorithm is evaluated using a collection of REST and SOAP APIs extracted from ProgrammableWeb.com.

A Study of Privacy Protection for Users of Electronic Money Using Blockchain Technology (블록체인 기법을 사용하는 전자화폐 사용자의 프라이버시 보호에 대한 연구)

  • Kang, Yong-Hyeog
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.10a
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    • pp.571-572
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    • 2017
  • The blockchain technology that implements electronic money uses decentralized computing and all transactions in a blockchain are open to everyone. This technique seems to guarantee anonymity by performing the transaction on the address instead of the user, but by using direction acyclic graph based on the transaction graph, the privacy problem is caused by tracking the addresses. In this paper, we analyze various techniques for centralized processing which makes it difficult to find the relevance on the graph in order to protect the privacy in the block chain technology. We also analyze the techniques of anonymizing in a distributed way to enhance privacy. Using the zero knowledge proof scheme guarantees full distributed anonymity but requires more computation and storage space, and various techniques to make this efficient are proposed. In this paper, we propose a privacy protection scheme of blockchain technology to integrate existing privacy protection techniques into a blockchain technology and perform it more efficiently with a centralized or decentralized technique.

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Stereoselective Synthesis of (2S,3R)-3-Hydroxyhomoserine Lactone via anti Selective Dihydroxylation of an OBO Group-Protected Vinyl Glycine Analog ((2S,3R)-3-하이드록시호모세린락톤의 입체선택적 합성 : 바이닐글라이신 OBO Ester 유도체의 입체선택적인 이중알콜화 반응)

  • Koh, Moo-hyun;Jeon, Jongho;Kim, Young Gyu
    • Applied Chemistry for Engineering
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    • v.31 no.2
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    • pp.187-192
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    • 2020
  • (2S,3R)-3-hydroxyhomoserine lactone (HSL) has been used as a key intermediate for the synthesis of various biologically active compounds. In this study, we demonstrated an efficient synthesis of HSL via anti selective dihydroxylation of a protected vinyl glycine analog with an oxabicyclo[2.2.2]octyl orthoester (OBO) ester group. Because the acyclic conformation of the substrate was efficiently controlled by the bulky OBO ester group, a diastereoselectivity of > 10 : 1 was obtained in the dihydroxylation reaction without the use of a chiral reagent. By using this result, the target compound 1 can be obtained from commercially available N-Cbz-L-serine 2 in seven steps with an overall yeid of 34%. This result could be applied to the stereoselective synthesis of biologically active molecules containing a vicinal amino diol moiety.

Analyses on the Workflow Critical Path (워크플로우 임계 경로에 관한 분석)

  • Son, Jin-Hyun;Chang, Duk-Ho;Kim, Myoung-Ho
    • Journal of KIISE:Databases
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    • v.28 no.4
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    • pp.677-687
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    • 2001
  • The critical path has been widely applied to many areas of computer engineering especially a directed acyclic graph. Its concept can also be useful in the context of a workflow. The workflow critical path is defined as a path which has the longest average execution time from the start activity to the end activity of workflow. Because there can be several concurrently executed workflow instances for a specific workflow a new method to determine the critical path should be developed. In this paper we specify our workflow queuing network model from which we can easily analyze many workflow characteristics. Based on this workflow model. we propose a method to identify the critical path In addition, we show come workflow areas which can utilze the critical path.

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Analysis of Guidance Laws for Impact Angle Control Mission of Cooperative Missiles Based on Communication Structure (협업 유도탄 간 상대 충돌 각 제어 임무에서 통신 구조에 따른 유도기법의 영향 분석)

  • Hyosang Ko;Danil Lee;Myunghwa Lee;Hanlim Choi
    • Journal of Aerospace System Engineering
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    • v.18 no.2
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    • pp.1-11
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    • 2024
  • This paper applies a relative impact angle control guidance law to a communication-based multi-missile network system with uncertainties and disturbances. The multi-missile network system is represented as a transitive reduction directed acyclic graph. Furthermore, this paper introduces both centralized and decentralized guidance laws based on the graph's structure. The relationship between these guidance laws is analyzed by comparing them based on the communication structure and the presence of system noise. To analyze the effects of decentralized optimal cooperative guidance law, this paper assumes uncertainty in missile dynamics and predicted impact point information for the relative impact angle control mission. Monte Carlo simulations are conducted for various mission environments to analyze the impact of communication and its structure on the system.

The Solvent Extraction of Silver Ion by Novel Sulfur-Containing Podans (황을 포함하는 새로운 포단드에 의한 은 이온의 용매추출)

  • Jung, Jong Hwa;Park, Jung Min;Kim, Dae Yeon;Lee, Shim Sung
    • Analytical Science and Technology
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    • v.7 no.2
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    • pp.225-232
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    • 1994
  • The podands I-VII, acyclic polyethers, expected high extractability for $Ag^+$ against $Pb^{2+}$ were designed and synthesized with high yields. Using podands I-VII as extractants, the %extraction(%Ex) of $Ag^+$ and $Pb^{2+}$ as picrates were determined in water/chloroform systems. The stability constants(log K) for the complexation of $Ag^+$ with podands I-VII were also determined by potentiometry. %Ex($Ag^+$) were proportional to the numbers of substituted sulfur donor atoms. Podand VI(log K : 7.65) having 3 substituted sulfur and podand VII(log K : 9.15) having 4 substituted sulfur, however, exhibited almost 100% of extractability, respectively. In %Ex($Ag^+/Pb^{2+}$, oxygen-sulfur mixed donor podands(IV-VII) showed the higher values. Otherwise, the values of log K and %Ex($Ag^+$) largely depended on the variation of donor-site of sulfur. From the results of NMR experiments, it seems that it is due to the ${\pi}-{\pi}$ stacking interaction between the aromatic end-groups.

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Leptin Is a Metabolic Signal for GnRH-LH/FSH Axis in Feed-restricted Ewes

  • Towhidi, A.;Khazali, H.;Zhandi, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.7
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    • pp.1039-1048
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    • 2007
  • Two experiments were conducted to determine whether leptin is a metabolic signal for gonadotropin secretion in ewes. In the first experiment, twenty-eight cyclic Chal ewes were assigned randomly to an energy restricted, no leptin group (ERNL) (60% of maintenance; n = 14) and an energy normal, no leptin group (ENNL) (100% of maintenance; n = 14) for 71 days (6 estrous cycles). Estrus was synchronized with seven consecutive injections of $PGF_{2{\alpha}}$ Biweekly, body weight (BW) and body condition score (BCS) were determined and blood samples were collected to measure plasma leptin concentration. Blood samples were also taken to determine plasma progesterone concentration twice weekly. After each PG injection from the second injection to the end of experiment, four ewes were selected and blood samples were collected at 20 minutes and at hourly intervals for 3 h to detect plasma LH and FSH concentration. In the second experiment, after the ceasing of the estrous cycle caused by energy restriction, six acyclic ewes were selected and randomly allotted to two groups (n = 3) and received the following treatment for four days. Ewes in an energy restricted, leptin group (ERL) were fed with a ration which provided 60% of maintenance energy requirements and intravenously injected with $4{\mu}g$ leptin/kg BW daily. Ewes in an energy excess, no leptin group (EENL) were fed with a ration that provided 180% (120%+60%) of maintenance energy requirements and intravenously injected with 1 ml saline daily. In both groups, blood samples were collected at 20 minutes and at hourly intervals for 3 h before feeding on d 0 and d 5, and for 3 h before and after injections as above on d 2 and d 4 to detect plasma LH and FSH concentration. In the first experiment, BW and BCS from the $2^{nd}$ estrous cycle, and leptin from the $3^{rd}$ estrous cycle to the end of the experiment significantly (p<0.05) decreased. In ERNL ewes, mean plasma concentrations of FSH significantly (p<0.01) decreased from the $4^{th}$ estrous cycle to d 71 and LH pulsatile secretion was suppressed on d 71, so that, mean plasma concentrations of LH (p<0.05), LH pulse frequency (p<0.01) and LH pulse amplitude (p<0.05) significantly decreased. In the second experiment, injection of leptin significantly increased mean circulating concentrations of LH (p<0.05), LH pulse frequency (p<0.01), LH pulse amplitude (p<0.05) and mean circulating concentrations of FSH (p<0.01) and leptin (p<0.01). High energy intake significantly (p<0.05) stimulated pulsatile secretion of LH and leptin secretion (p<0.01), but non-significantly increased plasma FSH concentration. The results of this study indicate that leptin is a metabolic signal for the GnRH-LH/FSH axis in feed-restricted fat-tailed ewes.

Comparison of Clinical Menifestations between Adolescents and Unmarried Young Women with Endometriosis in Daegu (대구 지역 청소년 및 미혼 여성 자궁내막증 환자의 임상 특성에 관한 비교연구)

  • Kim, Yoon-Jeong;Choi, Min-Hye;Chung, Min-Ji;Lee, Jung-Ho;Lee, Taek-Hoo
    • Clinical and Experimental Reproductive Medicine
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    • v.34 no.3
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    • pp.167-172
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    • 2007
  • Objective: The purpose of this study is to find out the differences of clinical characteristics of endometriosis and to emphasize the significance of early diagnosis of endometriosis to protect disease progression in adolescents. Methods: A retrospective analysis was carried out. All cases (n=130) were diagnosed surgically as endometriosis between January 2000 and August 2007 in two university hospitals in Daegu. Adolescents were 23 cases and unmarried young women were 107 cases. Data were collected through review of medical records. Results: The predominant symptom in adolescents was cyclic pain. 52.2% of adolescent patients were stage I or II. And stage III was 47.8% but stage IV was none. The other side 82.2% of unmarried young women patients were stage II or III and stage IV was 15.8%. Serum CA-125 level was elevated in adolescents, also. But there was no significant difference between the two groups. Conclusions: Endometriosis is progressive disease. Early diagnosis is necessary for prevention of the disease progression and free from pain. Appropriate gynecologic examination and careful concerns about adolescents are mandatory.

A Novel Task Scheduling Algorithm Based on Critical Nodes for Distributed Heterogeneous Computing System (분산 이기종 컴퓨팅 시스템에서 임계노드를 고려한 태스크 스케줄링 알고리즘)

  • Kim, Hojoong;Song, Inseong;Jeong, Yong Su;Choi, SangBang
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.3
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    • pp.116-126
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    • 2015
  • In a distributed heterogeneous computing system, the performance of a parallel application greatly depends on its task scheduling algorithm. Therefore, in order to improve the performance, it is essential to consider some factors that can have effect on the performance of the parallel application in a given environment. One of the most important factors that affects the total execution time is a critical path. In this paper, we propose the CLTS algorithm for a task scheduling. The CLTS sets the priorities of all nodes to improve overall performance by applying leveling method to improve parallelism of task execution and by reducing the delay caused by waiting for execution of critical nodes in priority phase. After that, it conditionally uses insertion based policy or duplication based policy in processor allocation phase to reduce total schedule time. To evaluate the performance of the CLTS, we compared the CLTS with the DCPD and the HCPFD in our simulation. The results of the simulations show that the CLTS is better than the HCPFD by 7.29% and the DCPD by 8.93%. with respect to the average SLR, and also better than the HCPFD by 9.21% and the DCPD by 7.66% with respect to the average speedup.

Profile Framework based on Web Services for Efficient Management of Profiles (효율적인 프로파일 운영을 위한 웹 서비스 기반의 프로파일 프레임워크)

  • Kim, Kyung-Sik;Lee, Jae-Dong
    • Journal of KIISE:Computing Practices and Letters
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    • v.13 no.1
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    • pp.11-23
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    • 2007
  • In this paper, we design and implement a framework based on Web Services for effective management of the profiles that were proposed to provide a user with personalized service. The profiles must be constituted the related information of the user and could be exchanged according to cyclic.acyclic or event among user's device, profile repository and service server for providing the user with personalized service. The profiles also must be supplied the services providers that need to the profiles for the personalized service. The profile framework is necessary to provide the functions like this for managing effectively of the personalized service. The proposed framework used the Web Services for exchanging and providing the profile regardless the various devices and platform. The framework also was applied the metadata constitute method and dynamic constitute method for managing effectively of the profile. The result of experiment using proposed framework was effective process and management of the profile and could exchange the profile with regardless of platform and device. The implemented system using the proposed framework was foundation of providing the personalized services with a user by through a effective management function of the profile.