• Title/Summary/Keyword: Periodic problems

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Research on Landscape Design by Flexibly Using Resilient Theory - Focused On 'New York High Line Park'- (리질리언트 이론을 활용한 경관 디자인에 관한 연구 - 'The High Line' 를 중심으로 -)

  • Chen, Wen-Li;Hong, Kwan-Seon
    • The Journal of the Korea Contents Association
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    • v.20 no.1
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    • pp.644-657
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    • 2020
  • As the development of urbanization has cause some environmental problems and natural disasters such as natural earthquakes and floods have brought about impact, designers have turned their attention to the independent prevention ability of urban ecosystems in face of environmental pollution and natural disasters, as well as its ability to adapt to the future. This study introduces 'elasticity theory' to discuss the practical application of elasticity design in landscapes and to solve the problem of lack of elasticity in space, which can provide more scientific reference meaning to create economic, cultural, and social values for space. After selecting 'The High Line' as the object, this paper investigates the previous theories and practical cases, and infers ecology, sustainability, diversity, and adaptability. And then this paper applies five components and analyzes the specific application of these five components of the landscape spatial elasticity strategy, and summarizes the application characteristics and influencing factors of elasticity design in 'The High Line' landscape planning. It can be known from the research that elasticity strategy which is reflected in the design process is the systematic management of landscape space. Elasticity design itself can strengthen environment quality and satisfy the requirements of the environment to defense external shocks so as to adapt to environment changes. Therefore, the elasticity design can strengthen the sustainable development of the city and establish a periodic recycle system.

An Approach to the Logistics Outsourcing Factors of the Korean Companies (한국 기업의 물류아웃소싱 활용요인에 관한 연구)

  • Bang, Hee-Seok;Park, Keun-Sik;Oh, Woon-Yul
    • Journal of Korea Port Economic Association
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    • v.25 no.4
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    • pp.21-44
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    • 2009
  • This study aims to understand the conditions for using logistics outsourcing of Korean enterprises, present existing problems, examine factors affecting utility, and analyze the pattern of logistics outsourcing based on contract term, and to ultimately contribute to enhancing competitiveness of logistics enterprises. Through the literature survey 8 factors were identified as three broad factors of corporate strategy, corporate characteristics, and environment. Factor analysis was conducted on the bases of 155 collected data among 400 distributions for 2 months from April to May in 2008. From the result of analysis, the implication and finding can be summarized into three aspects. Firstly, Korean companies value factors relative to corporate strategies as motivating factors for logistics outsourcing. Secondly, Korean companies consider logistics outsourcing depending on how to handle customers' demands and the severity of competition. Thirdly, it was found that product and organization characteristics are perceived as more important when contract term with logistics business is longer. The implications can be observed into two aspects. Firstly once the logistics outsourcing between manufacturers and logistics companies are determined, it was verified that mutual agreement, particular contracts and periodic communications can increase the outcome. Secondly the logistics outsourcing appeared to be different depending on the level of entering to foreign market and resulted in higher performance as well.

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ORTHODONTIC TREATMENT OF THE PALATALLY IMPACTED MAXILLARY CANINE (구개측 매복된 상악 견치의 교정적 치험례)

  • Kam, Dong-Hoon;Kim, Jung-Wook;Hahn, Se-Hyun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.25 no.1
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    • pp.127-133
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    • 1998
  • An impacted tooth is defined pathologically as a tooth that remains under the mucosa of inside bone without eruption of the crown after a specific period of eruption. Clinically, the term includes those teeth, even before eruption period, that are not expected to erupt due to shape, position and alignment of tooth and lack of space. Canine is prone to impaction more than other teeth because it has the longest time to develop and a complex route from the place of formation to the site of eruption. The impaction incidence of maxillary canine is repoted 0.92$\sim$3.3% (Ferguson, 1990). In 1995 Orton reported that the incidence was 0.92$\sim$2.2% and palatal impaction was more frequent than labial impaction(85%:15%). In 1969 Johnston presented it was more common to woman than to man(3:1). The etiology includes systemic disease such as endocrine disorder, cleidocranial dysostosis, irradiation, Crouzon syndrome, ricketts, facial hemihypertrophy and hereditary and local problems such as ectopic position of the tooth, distance of tooth from its place of eruption, malformation of the tooth, presence of supernumerary teeth, trauma of tooth germ, infection of tooth germ, displacement of tooth germ or tooth by a neoplasm, ankylosis, overretention of deciduous predecessor, lack of space for the tooth in the dental arch and mucosal barrier due to gingival fibrosis. The maxillary canine is especially important as it has the longest root, provides guidance for lateral movement of the mandible and masticatory function and assumes an important role esthetically as it is located at mouth angle. If left untreated, it may cause migration and external, internal resorption of adjacent teeth, loss of arch length, formation of dentigerous cyst or tumors, infection and referred pain as well as malposition of the tooth. Therefore, periodic examination of the development and eruption of the maxillary canine is especially important in a growing child. This case study presents the results of treatment of palatally impacted maxillary canine utilizing surgical exposure and orthodontic tooth movement on patients visiting SNUDH dept. of pediatric dentistry.

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Comparisons on the worker's health status and working environment between small and large industries in Kyeungin industrial complex (경인지역 대규모 사업장과 소규모 사업장의 작업환경 및 종사 근로자의 질병 이환율 비교)

  • Won, Jong-Uk;Song, Jae-Suk;Roh, Jae-Hoon
    • Journal of Preventive Medicine and Public Health
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    • v.30 no.2 s.57
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    • pp.392-401
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    • 1997
  • Generally working environment and worker's health status of small scale industries (SSI) which employ less than 50 workers are known to be poorer than those of large scale industries(LSI) which employ more than 500 workers. However, according to the analysis of occupational injuries in Korea, prevalence rate of occupational injuries of SSI was 3.1 times as high as LSI. But there was no difference in prevalence rate of occupational disease and werkers with suspected occupational disease(D1) between SSI and LSI. To confirm these two different facts, we surveyed working environment and worker's health status of SSI and LSI in Kyeungin industrial complex. Workers in SSI were 10,878 and workers in LSI were 8,291 and number of hazardous agents in SSI were 3,554 and those of LSI were 1,916. We found following results. First, proportion of male workers and workers who were less than 30 yens old and more than 50 yens old was higher in SSI compared to LSI. Second, worker in SSI had more liver disease, viral hepatitis, and pneumoconiosis than in LSI, and there were more worker with suspected occupational disease, general disease, and worker needed close observation in SSI. But these effects had not statistical significance under the condition controlled by age and sex with logistic regression. Third, the numbers measured for specific chemicals, organic solvents, and heavy metals in SSI was more than in LSI. However there was on difference in the excess rate of each hazardous agent between SSI and LSI. As the above results workers' health status in SSI was poorer than in LSI, but these results were mainly due to the population structure difference. Although there were some limitation of this study and problems of sensitivity and validity for periodic health examination and working environment evaluation method, the concept that working environment and worker's health status in SSI should be reviewed. In future the study that will reveal the real weak point of SSI should be performed.

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A Query Result Integrity Assurance Scheme Using an Order-preserving Encryption Scheme in the Database Outsourcing Environment (데이터베이스 아웃소싱 환경에서 순서 보존 암호화 기법을 이용한 질의 결과 무결성 검증 기법)

  • Jang, Miyoung;Chang, Jae Woo
    • Journal of KIISE
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    • v.42 no.1
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    • pp.97-106
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    • 2015
  • Recently, research on database encryption for data protection and query result authentication methods has been performed more actively in the database outsourcing environment. Existing database encryption schemes are vulnerable to order matching and counting attack of intruders who have background knowledge of the original database domain. Existing query result integrity auditing methods suffer from the transmission overhead of verification object. To resolve these problems, we propose a group-order preserving encryption index and a query result authentication method based on the encryption index. Our group-order preserving encryption index groups the original data for data encryption and support query processing without data decryption. We generate group ids by using the Hilbert-curve so that we can protect the group information while processing a query. Finally, our periodic function based data grouping and query result authentication scheme can reduce the data size of the query result verification. Through performance evaluation, we show that our method achieves better performance than an existing bucket-based verification scheme, it is 1.6 times faster in terms of query processing time and produces verification data that is 20 times smaller.

A Resilient Key Renewal Scheme in Wireless Sensor Networks (센서 네트워크에서 복원력을 지닌 키갱신 방안)

  • Wang, Gi-Cheol;Cho, Gi-Hwan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.2
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    • pp.103-112
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    • 2010
  • In sensor networks, because sensors are deployed in an unprotected environment, they are prone to be targets of compromise attack, If the number of compromised nodes increases considerably, the key management in the network is paralyzed. In particular, compromise of Cluster Heads (CHs) in clustered sensor networks is much more threatening than that of normalsensors. Recently, rekeying schemes which update the exposed keys using the keys unknown to the compromised nodes are emerging. However, they cause some security and efficiency problems such as single group key employment in a cluster, passive eviction of compromised nodes, and excessive communication and computation overhead. In this paper, we present a proactive rekeying scheme using renewals of duster organization for clustered sensor networks. In the proposed scheme, each sensor establishes individual keys with neighbors at network boot-up time, and these keys are employed for later transmissions between sensors and their CH. By the periodic cluster reorganization, the compromised nodes are expelled from network and the individual keys employed in a cluster are changed continuously. Besides, newly elected CHs securely agree a key with sink by informing their members to sink, without exchangingany keying materials. The simulation results shows that the proposed scheme remarkably improves the confidentiality and integrity of data in spite of the increase of compromised nodes. Also, they show that the proposed scheme exploits the precious energy resource more efficiently than SHELL.

DENTAL MANAGEMENT OF A PATIENT WITH MUSCULAR DYSTROPHY UNDER GENERAL ANESTHESIA: CASE REPORT (근이영양증(muscular dystrophy) 환자의 전신마취 하 치과치료 : 증례보고)

  • Chae, Jong Kyun;Song, Ji-Soo;Shin, Teo Jeon;Hyun, Hong-Keun;Kim, Jung-Wook;Jang, Ki-Taeg;Lee, Sang-Hoon;Kim, Young-Jae
    • The Journal of Korea Assosiation for Disability and Oral Health
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    • v.15 no.1
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    • pp.50-54
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    • 2019
  • Muscular dystrophy (MD) is a heterogeneous group of inherited neuromuscular disorders, characterized by progressive muscle weakness. Severity of the disease ranges from mild to severe, and the disease is mostly caused by mutations in a number of genes. These genetic mutations cause lack of proteins which are essential for muscle cell stability. Muscle fibers are gradually replaced by fat and fibrous tissue. The muscles of the head and neck are affected in several types of MD that manifest as altered craniofacial morphology and dental malocclusion. A 3-year-10-month old, 15.0 kg boy with MD presented to Seoul National University Dental Hospital, Seoul, South Korea because of extensive carious teeth. A number of dental caries in primary dentition were identified during clinical oral examination. Due to dental anxiety and underlying systemic disease, general anesthesia was considered. General anesthesia was induced and maintained with intravenous anesthetics, propofol and remifentanil. Caries treatments - resin restoration, pulpectomy, zirconia crown restoration, stainless steel crown restoration - were performed. Under general anesthesia, successful dental procedure was done. Total intravenous anesthesia (TIVA) was performed instead of inhalation anesthesia in order to avoid risk of complications such as malignant hyperthermia and life-threatening rhabdomyolysis. With decreasing muscle function, plaque control becomes more difficult and leads to gingivitis. Especially, the open-mouth posture worsens gingivitis and can leads to malocclusions and problems in swallowing. Regular and periodic dental care is essential for maintaining oral health for patients with MD.

A Study on the Framework and Arrangement of Interior Column in Single-Story Buddhist Halls (단층 불전 내주의 결구 및 배열 방식에 관한 연구)

  • Lee, U-Jong;Jeon, Bong-Hui
    • Korean Journal of Heritage: History & Science
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    • v.33
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    • pp.210-255
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    • 2000
  • This study aims to classify the framework and arrangement of interior columns (Naeju) which are used in single-story Buddhist halls into several types, and to develop a theory on the process of changes among those types. Since interior columns are building materials which hold up the roof structure and make partitions in the interior space of halls, their framework and arrangement is closely linked to the development of building technology and is expected to reflect new architectural needs. The kinds of interior columns classified by the shape of framework are goju, chaduju, oepyonju, naepyonju. The arrangement of interior columns can he classified by two methods: One which counts the number of the interior column arrangements in a hall, and the other whose classification relates with the side wall columns - Jeongchibup and yijubup. With the combination of these classifications, we can divide the framework and arrangement of interior columns into 8 types From the remains of Korean and Chinese Architecture, we can presume that before the late-Goryo period, jeongchibup had always been applied in the construction of Buddhist halls, and gamju(column reducing) had only been used in examples of small scale. After the founding of Choseon Kingdom, however, national policy had weakened the economic power of Buddhist temples. Because of that, large-scale outdoor Buddhist mass was replaced by small-scale indoor mass, and for this reason, though the scale of Buddhist halls became smaller, the need for a broad interior space became stronger. Thus in early-Choseon period, reduction of interior columns became widely spread. Those types of framework and arrangement of interior columns where yijubup was applied were developed because the rear interior columns arrangements, in order to expand the interior space, have moved backward. Among these types, yiju-goju and yiju-chaduju were developed for the Buddhist halls with paljak roof(hipped-gabled roof), where the load of their side eaves caused structural problems at the side walls. And oepyonju type was for the small-scale and middle-scale Buddhist halls which needed more interior space but didn't want the extension of roof structure. From the local and periodic distribution of each types, we can conclude that the types jeongchi-goju, jeongchi-chaduju and yiju-chaduju have been settled as typical technique of local carpenters. Oepyonju was developed later than the other types, but for its merit of low cost, it became a popular type across the nation.

A study on The Improvement Plan of The Restricted Development Zone Monitoring system (개발제한구역 모니터링체계 개선방안 연구)

  • Lee, Se-won
    • Journal of Cadastre & Land InformatiX
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    • v.52 no.1
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    • pp.17-36
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    • 2022
  • The purpose of this study is to diagnose problems in the regulation and management of Restricted Development Zone and to prepare a construction plan to convert it to a data-based monitoring system. Unlike other land-use zones, the Restricted Development Zone is a exceptional zone that prohibits all development activities other than the minimum maintenance and must be strictly controlled and managed by the local government. However, the current Restricted Development Zone management is distributed according to the conditions of each local government, and it is not possible to monitor changes in the entire Restricted Development Zone as shown in the survey results. In particular, in this study, by introducing an AI-based monitoring system, MOLIT sends the results of detecting changes across the country at regular time points(monthly and quarterly) to the local governments based on the same regulation standards, and the local governments can be trusted while inputting the regulation results into the system. To propose this methodology, first, a survey and interview were conducted with local government officials and experts. Second, we analyzed cases in which AI analysis was applied to local governments and proposed a plan to improve the efficiency of regulation work according to the introduction of the monitoring system. Third, a plan was prepared to establish a monitoring system based on the advancement of the management information system. This monitoring system can be expanded and applied to land that needs periodic regulation and management in the future, and this study tried to propose a methodology and policy for this.

A prospective multicenter clinical study on the efficiency of detachable ball- and spring-retained implant prosthesis

  • Min-Jung Kim;Won-Tak Cho;Su-Hyun Hwang;Ji-Hyeon Bae;Eun-Bin Bae;June-Sung Shim;Jong-Eun Kim;Chang-Mo Jeong;Jung-Bo Huh
    • The Journal of Advanced Prosthodontics
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    • v.15 no.4
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    • pp.202-213
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    • 2023
  • PURPOSE. This prospective clinical study was conducted to evaluate the clinical usefulness of the freely detachable zirconia ball- and spring-retained implant prosthesis (BSRP) through a comparative analysis of screw- and cement-retained implant prosthesis (SCRP). MATERIALS AND METHODS. A multi-center, randomized, prospective clinical study evaluating the clinical usefulness of the detachable zirconia ball- and spring-retained implant prostheses was conducted. Sixty-four implant prostheses in 64 patients were examined. Periodic observational studies were conducted at 0, 3, 6, and 12 months after delivery of the implant prosthesis. Factors such as implant success rate, marginal bone resorption, periodontal pocket depth, plaque and bleeding index, and prosthetic complications were evaluated, respectively. RESULTS. During the 1-year observation period, all implants survived without functional problems and clinical mobility, showing a 100% implant success rate. Marginal bone resorption was significantly higher in the SCRP group than in the BSRP group only at the time of implant prosthesis delivery (P = .043). In all observation periods, periodontal pocket depth was slightly higher in the BSRP group than in the SCRP group, but there was no significant difference (P > .05). The modified plaque index (mPI) scores of both groups were moderate. Higher ratio of a score 2 in modified sulcus bleeding index (mBI) was observed in the BSRP group in the 6- and 12-months observation. CONCLUSION. Within the limitations of this study, the newly developed zirconia ball- and spring-retained implant prosthesis could be considered as an applicable and predictable treatment method along with the existing screw- and cement-retained prosthesis.