• Title/Summary/Keyword: Centralization

Search Result 259, Processing Time 0.03 seconds

Influences of Organizational Structure on Organizational Culture and Job Satisfaction in Construction Management Site Organizations (건설사업관리 현장조직의 조직구조가 조직문화 및 직무만족에 미치는 영향)

  • An, Sung-Hoon;Umuhoza, Esperance
    • Journal of the Korea Institute of Building Construction
    • /
    • v.21 no.3
    • /
    • pp.241-247
    • /
    • 2021
  • As construction projects become more complex and larger, the role of the organization becomes more important. In order to increase the performance of the construction management(CM) site organization, it is necessary to find an organizational structure suitable for the CM, lead an organizational culture correctly, and increase the job satisfaction of the members. Therefore, the purpose of this study is to study the influence of the organizational structure of the CM site organization on the organizational culture and job satisfaction. As results of the study, the organizational structure of the CM site organization was the highest at 3.51 for formalization and the lowest at 2.71 for centralization(out of 5). In addition, as results of correlation analysis, organizational structure was found to have a correlation with organizational culture and job satisfaction. This study is considered to be helpful in planning an organizational structure suitable for the CM site organization.

Posterior decentering of the humeral head in patients with arthroscopic rotator cuff repair

  • Nakamura, Hidehiro;Gotoh, Masafumi;Honda, Hirokazu;Mitsui, Yasuhiro;Ohzono, Hiroki;Shiba, Naoto;Kume, Shinichiro;Okawa, Takahiro
    • Clinics in Shoulder and Elbow
    • /
    • v.25 no.1
    • /
    • pp.22-27
    • /
    • 2022
  • Background: In some patients with rotator cuff tear (RCT), the axial view of magnetic resonance imaging (MRI) shows subtle posterior decentering (PD) of the humeral head from the glenoid fossa. This is considered to result from a loss of centralization that is typically produced by rotator cuff function. There are few reports on PD in RCT despite the common occurrence of posterior subluxation in degenerative joint disease. In this study, we investigated the effect of PD in arthroscopic rotator cuff repair (ARCR). Methods: We conducted a retrospective study of consecutive patients who underwent ARCR at our institute and were followed-up for at least 1 year. PD was identified as a 2-mm posterior shift of the humeral head relative to the glenoid fossa in the axial MRI view preoperatively. The tear size and fatty degeneration (FD, Goutallier classification) were also evaluated using preoperative MRI. Retears were evaluated through MRI at 1 year postoperatively. Results: We included 135 shoulders in this study. Ten instances of PD (including seven retears) were observed preoperatively. Fifteen retears (three and 12 retears in the small/medium and large/massive tear groups, respectively) were observed postoperatively. PD was significantly correlated with tear size, FD, and retear occurrence (p<0.01 each). The odds ratio for PD in retears was 34.1, which was greater than that for tear size ≥3 cm and FD grade ≥3. Conclusions: We concluded that large tear size and FD contribute to the occurrence of PD. Furthermore, PD could be a predictor of retear after ARCR.

Blockchain-Based Smart Home System for Access Latency and Security (지연시간 및 보안을 위한 블록체인 기반 스마트홈 시스템 설계)

  • Chang-Yu Ao;Kang-Chul Kim
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.18 no.1
    • /
    • pp.157-164
    • /
    • 2023
  • In modern society, smart home has become a part of people's daily life. But traditional smart home systems often have problems such as security, data centralization and easy tampering, so a blockchain is an emerging technology that solves the problems. This paper proposes a blockchain-based smart home system which consists in a home and a blockchain network part. The blockchain network with 8 nodes is implemented by HyperLeger Fabric platform on Docker. ECC(Elliptic Curve Cryptography) technology is used for data transmission security and RBAC(role-based access control) manages the certificates of network members. Raft consensus algorithm maintains data consistency across all nodes in a distributed system and reduces block generation time. The query and data submission are controlled by the smart contract which allows nodes to safely and efficiently access smart home data. The experimental results show that the proposed system maintains a stable average query and submit time of 84.5 [ms] and 93.67 [ms] under high concurrent accesses, respectively and the transmission data is secured through simulated packet capture attacks.

Planning and Establishment of Sejong City Smart City (세종시 스마트시티 구상 및 수립 방안)

  • Park, Jungsu;Jung, Hanmin
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2021.10a
    • /
    • pp.161-163
    • /
    • 2021
  • This urban centralization is expected to develop rapidly, with 75% of the population living in the city by 2035. Large cities are becoming unsustainable due to side effects such as environmental pollution, severe traffic jams, excessive energy depletion, and destruction of the natural ecosystem. In addition, the happiness index of citizens of large cities is also falling because of high crime rates and safety accidents, the work-life imbalance caused by inequality and polarization, and overly competitive education. To solve this problem, Smart City, an IT-based future city model, was born. The Korean government is also actively attempting to improve urban competitiveness and promote sustainable development through efficient construction and operation of smart cities as a national focus project. To support the effort, we review the basic directions and strategies of Sejong City's Smart City service infrastructure based on the comprehensive national land plan, Smart City plan, and Smart City strategy plan.

  • PDF

Distributed AI Learning-based Proof-of-Work Consensus Algorithm (분산 인공지능 학습 기반 작업증명 합의알고리즘)

  • Won-Boo Chae;Jong-Sou Park
    • The Journal of Bigdata
    • /
    • v.7 no.1
    • /
    • pp.1-14
    • /
    • 2022
  • The proof-of-work consensus algorithm used by most blockchains is causing a massive waste of computing resources in the form of mining. A useful proof-of-work consensus algorithm has been studied to reduce the waste of computing resources in proof-of-work, but there are still resource waste and mining centralization problems when creating blocks. In this paper, the problem of resource waste in block generation was solved by replacing the relatively inefficient computation process for block generation with distributed artificial intelligence model learning. In addition, by providing fair rewards to nodes participating in the learning process, nodes with weak computing power were motivated to participate, and performance similar to the existing centralized AI learning method was maintained. To show the validity of the proposed methodology, we implemented a blockchain network capable of distributed AI learning and experimented with reward distribution through resource verification, and compared the results of the existing centralized learning method and the blockchain distributed AI learning method. In addition, as a future study, the thesis was concluded by suggesting problems and development directions that may occur when expanding the blockchain main network and artificial intelligence model.

Effects of Spinal Mobilization with Leg Movement and Neural Mobilization on Pain, Mobility, and Psychosocial Functioning of Patients with Lumbar Disc Herniation: A Randomized Controlled Study

  • Seung Jin Kim;Ho Young Jang;Suk-Min Lee
    • Physical Therapy Rehabilitation Science
    • /
    • v.12 no.2
    • /
    • pp.92-104
    • /
    • 2023
  • Objective: The purpose of this study was to investigate the effect of spinal mobilization with leg movement (SMWLM) and neural mobilization (NM) in patients with lumbar disc herniation (LDH) accompanied by radiating pain. Design: Three-group pre-test-post-test control group design. Methods: We enrolled 48 participants, whom we randomly assigned to three groups. The SMWLM group (n=16) underwent 20 min of conventional physical therapy (CT) and 20 min of SMWLM. The NM group (n=16) underwent 20 min of CT and 20 min of NM. The control group (n=16) underwent 20 min of CT. These interventions in all the groups were performed three times a week for 4 weeks. Numeric pain rating score (NPRS), body grid chart score (BGCS), passive straight leg raise (PSLR), active lumbar flexion range of motion (ALFROM), korean version oswestry disability index (KODI), and korean version fear avoidance beliefs questionnaire (KFABQ) were measured pre- and post-intervention. Results: In all three groups, the NPRS, PSLR, KODI, and KFABQ scores were significantly different pre- and post-intervention (p<0.05). Significant differences were observed in BGCS and ALFROM in the SMWLM and NM groups pre- and post-intervention (p<0.05). The SMWLM group showed more improvement in the NPRS of leg pain, ALFROM, and KFABQ score than that exhibited by the NM and control groups (p<0.05). Conclusions: Both SMWLM and NM were effective for improving back and leg pain, centralization of symptoms, mechanical sensitivity, lumbar mobility, lumbar functional disability, and psychosocial functioning in patients with LDH with radiating pain.

Factors on the Social Welfare Expenditures of the Local Governments (지방정부의 정부 간 관계가 기초지방정부의 사회복지비지출에 미치는 영향에 관한 연구)

  • Kim, Seung Yun;Hong, Kyung Zoon
    • Korean Journal of Social Welfare Studies
    • /
    • v.42 no.3
    • /
    • pp.207-231
    • /
    • 2011
  • The purpose of this study is to investigate the effect of the intergovernment relationship on the local government's social welfare expenditure. The data of 230 local governments from 2003 to 2008 were analyzed with the PCSE(Panel Corrected Standard Errors) Model of Beck and Kats. The results were as follow. First, financial transfer from the higher governments increase the social welfare expenditure of the local governments. Second, the party structure, that is the political relationships among local, regional, and central governments, affect the social welfare expenditure of the local governments. Third, the local governments compete each other to expand the social welfare expenditure in Korea. These results suggest that the relationship of local governments with the higher ones as well as the community factors is important in Korea, where the centralization is still strong in the local autonomy system, to understand the development of social welfare.

Predicting the Performance of Recommender Systems through Social Network Analysis and Artificial Neural Network (사회연결망분석과 인공신경망을 이용한 추천시스템 성능 예측)

  • Cho, Yoon-Ho;Kim, In-Hwan
    • Journal of Intelligence and Information Systems
    • /
    • v.16 no.4
    • /
    • pp.159-172
    • /
    • 2010
  • The recommender system is one of the possible solutions to assist customers in finding the items they would like to purchase. To date, a variety of recommendation techniques have been developed. One of the most successful recommendation techniques is Collaborative Filtering (CF) that has been used in a number of different applications such as recommending Web pages, movies, music, articles and products. CF identifies customers whose tastes are similar to those of a given customer, and recommends items those customers have liked in the past. Numerous CF algorithms have been developed to increase the performance of recommender systems. Broadly, there are memory-based CF algorithms, model-based CF algorithms, and hybrid CF algorithms which combine CF with content-based techniques or other recommender systems. While many researchers have focused their efforts in improving CF performance, the theoretical justification of CF algorithms is lacking. That is, we do not know many things about how CF is done. Furthermore, the relative performances of CF algorithms are known to be domain and data dependent. It is very time-consuming and expensive to implement and launce a CF recommender system, and also the system unsuited for the given domain provides customers with poor quality recommendations that make them easily annoyed. Therefore, predicting the performances of CF algorithms in advance is practically important and needed. In this study, we propose an efficient approach to predict the performance of CF. Social Network Analysis (SNA) and Artificial Neural Network (ANN) are applied to develop our prediction model. CF can be modeled as a social network in which customers are nodes and purchase relationships between customers are links. SNA facilitates an exploration of the topological properties of the network structure that are implicit in data for CF recommendations. An ANN model is developed through an analysis of network topology, such as network density, inclusiveness, clustering coefficient, network centralization, and Krackhardt's efficiency. While network density, expressed as a proportion of the maximum possible number of links, captures the density of the whole network, the clustering coefficient captures the degree to which the overall network contains localized pockets of dense connectivity. Inclusiveness refers to the number of nodes which are included within the various connected parts of the social network. Centralization reflects the extent to which connections are concentrated in a small number of nodes rather than distributed equally among all nodes. Krackhardt's efficiency characterizes how dense the social network is beyond that barely needed to keep the social group even indirectly connected to one another. We use these social network measures as input variables of the ANN model. As an output variable, we use the recommendation accuracy measured by F1-measure. In order to evaluate the effectiveness of the ANN model, sales transaction data from H department store, one of the well-known department stores in Korea, was used. Total 396 experimental samples were gathered, and we used 40%, 40%, and 20% of them, for training, test, and validation, respectively. The 5-fold cross validation was also conducted to enhance the reliability of our experiments. The input variable measuring process consists of following three steps; analysis of customer similarities, construction of a social network, and analysis of social network patterns. We used Net Miner 3 and UCINET 6.0 for SNA, and Clementine 11.1 for ANN modeling. The experiments reported that the ANN model has 92.61% estimated accuracy and 0.0049 RMSE. Thus, we can know that our prediction model helps decide whether CF is useful for a given application with certain data characteristics.

Determinants and Processes of IT Consolidation: A Case Study of Korean Conglomerates (IT 통합의 결정 요인과 과정: 국내 대기업들에 대한 사례 연구)

  • Zo, Hang-Jung;Song, Chan-Hoo;Han, Seung-Hun
    • Information Systems Review
    • /
    • v.10 no.3
    • /
    • pp.223-255
    • /
    • 2008
  • This study explores the determinants and processes of IT consolidation of Korean conglomerates. Through an extensive analysis of cases, this study identifies the drivers, benefits and critical success factors of IT consolidation, and observes the transition of vision for the IT service subsidiaries in the conglomerates. The results show that most firms in this analysis have completed the organizational, physical, and logical consolidation of their IT resources, and currently some of them are preparing for the next stage of IT consolidation such as rational consolidation and virtualization. It is also found that the strategic factor was one of the most significant determinants in consolidating IT resources which leaded the transition of vision of the IT service firms in the conglomerates from "cost center" to "profit center". The results of this study can provide a fundamental and empirical basis for building a theory of IT consolidation, and be used as a valuable benchmarking model for the organizations which consider starting a project of IT consolidation.

Teacher Knowledge Necessary to Analyze Student's Errors and Difficulties about the Concept of Irrational Numbers (무리수 개념에 관한 학생의 오류와 어려움 해석에 필요한 교사지식)

  • Kang, Hyangim;Choi, Eunah
    • School Mathematics
    • /
    • v.19 no.2
    • /
    • pp.319-343
    • /
    • 2017
  • In this study, we hope to reveal specialized content knowledge(SCK) and its features necessary to analyze student's errors and difficulties about the concept of irrational numbers. The instruments and interview were administered to 3 in-service mathematics teachers with various education background and teaching experiments. The results of this study are as follows. First, specialized content knowledge(SCK) were characterized by the fixation to symbolic representation like roots when they analyzed the concentration and overlooking of the representations of irrational numbers. Secondly, we observed the centralization tendency on symbolic representation and the little attention to other representations as the standard of judgment about irrational numbers. Thirdly, In-service teachers were influenced by content of students' error when they analyzed the error and difficulties of students. Lately, we confirmed that the content knowledge about the viewpoint of procept and actual infinity of irrational numbers are most important during the analyzing process.