• Proceedings of the KSME Conference
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• 2008.11a
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• pp.523-528
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• 2008

An open frame structure is fastened by bolt joints for strength and shock attenuation. Therefore the full finite element model of an open frame structure should be properly modeled including bolt joints for strength analysis of the frames and joint assemblies which are operated under multi-loading conditions such as driving, drop, inertia and torsional loads. Then the joints and frames must satisfy the specified allowable strength constraints. Because the full finite element model has a large number of elements to perform strength analysis, a detailed fine bolt analysis seems to be very expensive. Therefore bolts of the full finite element model are approximately modeled by constraints equations to constrain degree of freedoms between adjacent nodes. However, the constraints equation method can exaggerate stress results at the constrained nodes. Thus a detailed bolt analysis and a theoretical/experiential formula of bolts for a worst bolt joint are performed using reaction force applied both bolt and bolt joint. Finally, the results from the two methods are compared and discussed to verify the safety of the open frame structure.

• KIEAE Journal
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• v.13 no.2
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• pp.151-156
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• 2013

This study examines the properties of spaces where historical and cultural resources have been preserved in the street system of Daegu Yakryeong market district, by using Space Syntax methodology. The results were obtained through ASA(Angular Segment Analysis) on each node (spatial unit) in the street network. An overall characteristic of spatial configuration in street system of the surveyed district is that nodes in the street network tend to form socially integrated spatial structure to allow easy access to each space in the system. There are a small number of socially isolated spaces in the street system, which are located at nodes in narrow streets adjacent to the roadway outside the district, or in narrow alleys between early modern Korean buildings. More than half of the surveyed spaces have high levels of social integration, which contain buildings playing a central role of the community, a traditional street market, symbolic landmarks. In conclusion, it is expected that the achievements of this study will contribute in leading to rational land use planning for sound and sustainable development of historical and cultural resources in an urban district.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.3 no.3
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• pp.331-343
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• 2009

Many types of sensor data exhibit strong correlation in both space and time. Both temporal and spatial suppressions provide opportunities for reducing the energy cost of sensor data collection. Unfortunately, existing clustering algorithms are difficult to utilize the spatial or temporal opportunities, because they just organize clusters based on the distribution of sensor nodes or the network topology but not on the correlation of sensor data. In this paper, we propose a novel clustering algorithm based on the correlation of sensor data. We modify the advertisement sub-phase and TDMA schedule scheme to organize clusters by adjacent sensor nodes which have similar readings. Also, we propose a spatio-temporal suppression scheme for our clustering algorithm. In order to show the superiority of our clustering algorithm, we compare it with the existing suppression algorithms in terms of the lifetime of the sensor network and the size of data which have been collected in the base station. As a result, our experimental results show that the size of data is reduced and the whole network lifetime is prolonged.

• Journal of Welding and Joining
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• v.34 no.2
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• pp.11-15
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• 2016

FE analyses for weldment of ship structure are required for various reasons such as stress concentration for bead tow, residual stress and distortion after welding, and hydrogen diffusion for prediction of low temperature crack. These analyses should be done by solid element modeling, but most of ship structures are modeled by shell element. If we are able to make solid element in the shell element FE modeling it is easily to solve the requirement for solid elements in weld analysis of large ship structures. As the nodes of solid element cannot take moments from nodes of shell element, these two kinds of element cannot be used in one model by conventional modeling. The PSCM (Perpendicular shell coupling method) can connect shell to solid. This method uses dummy perpendicular shell element for transferring moment from shell to solid. The target of this study is to develop a FE pre-processing system applicable at welding at ship structure by using PSCM. We also suggested glue-contact technique for controlling element numbers and element qualities and applied it between PSCM and solid element in automatic pre-processing system. The FE weldment modeling through developed pre-processing system will have rational stiffness of adjacent regions. Then FE results can be more reliable when turn-over of ship-block with semi-welded state or ECA (Engineering critical assessment) of weldment in a ship-block are analyzed.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.4
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• pp.530-536
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• 2008

Localization is one of the fundamental problems in wireless sensor networks (WSNs) that forms the basis for many location-aware applications. Localization in WSNs is to determine the position of node based on the known positions of several nodes. Most of previous localization method use triangulation or multilateration based on the angle of arrival (AOA) or distance measurements. In this paper, we propose an enhanced centroid localization method based on edge weights of adjacent nodes using fuzzy modeling and genetic algorithm when node connectivities are known. The simulation results shows that our proposed centroid method is more accurate than the simple centroid method using connectivity only.

• Journal of Digestive Cancer Research
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• v.11 no.1
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• pp.49-54
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• 2023

Colorectal cancers often invade adjacent organs; however, direct duodenal invasion is rare. Adenocarcinoma is the most common type of colorectal cancer, but an undifferentiated carcinoma type is unusual. Herein, we present a case of undifferentiated carcinoma of the colon that directly invaded the duodenum and metastasized to distant lymph nodes. An 85-year-old female patient was admitted with a 7-cm-sized colonic mass invading the duodenum, detected by computed tomography. Positron emission tomography revealed fluorodeoxyglucose uptake in the colon, duodenum, and aortocaval lymph nodes. A large encircling mass in the ascending colon and an ulcerated mass in the duodenum were revealed by colonoscopy and esophagogastroduodenoscopy, respectively. Pathologic examinations of the colon and the duodenum revealed nonglandular, diffusely infiltrating atypical round cells, confirming undifferentiated carcinoma of the colon. The histologic type of this tumor was distinguished using immunohistochemical (IHC) markers. Finally, microscopic characteristics and IHC markers aided in identifying the histologic type of colorectal cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4347-4351
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• 2012

Background: Breast cancer is the most common cancer of women and the principal cause of death in middle aged women. The objective of this study was to describe the trend of breast cancer and its management in Aden and adjacent south-eastern governorates of Yemen during the last 20 years. Patients and Methods: This is a retrospective analysis of previous studies on patients with breast cancer in Aden and adjacent south-eastern governorates, Yemen (January 1989 through December 2007). The studied variables were: sex, age, time and type of presentation, disease stage, pathological types and the performed surgical treatment. The sources of information were the treatment registry of Aden health office, archives of Al-Gamhouria teaching hospital; major referral and other public and private hospitals in Aden and Aden Cancer Registry. Results: The total number of patients was 476, 99% being females. The age range was 19-88 years. The most affected age was 30-50 years (60.5%), 95% presenting after one month of having breast symptoms. Forty-five percent presented with signs of advanced local disease, while 59.2% had palpable axillary lymph nodes on presentation. Early breast cancer (stages I-II) occurred in 47%, and late breast cancer (stages III-IV) in 51.5%. Invasive ductal carcinoma was the commonest pathology (89.3%). The main surgical treatment was mastectomy (modified radical mastectomy (50%). Conclusion: Breast cancer is predominantly a disease of young with late presentation and advanced disease. Improving health awareness and earlier diagnosis of the disease by health education, encouraging breast self-examination, and providing the mammography equipment and mammary clinics in hospitals are recommended. Establishment of oncology and radiotherapy centers in Aden is a necessity.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.4
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• pp.774-784
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• 2009

A wireless sensor network consisting of a large number of nodes with limited battery power should minimize energy consumption at each node to prolong the network lifetime. To improve the sensitivity of wireless sensor networks, an efficient scheduling algorithm and energy management technology for minimizing the energy consumption at each node is desired. ill this paper, we propose energy-aware routing mechanism for maximum lifetime and to optimize the solution quality for sensor network maintenance and to relay node from its adjacent cluster heads according to the node"s residual energy and its distance to the base station. Proposed protocol may minimize the energy consumption at each node, thus prolong the lifetime of the system regardless of where the sink is located outside or inside the cluster. Simulation results of proposed scheme show that our mechanism balances the energy consumption well among all sensor nodes and achieves an obvious improvement on the network lifetime. To verify propriety using NS-2, proposed scheme constructs sensor networks adapt to current model and evaluate consumption of total energy, energy consumption of cluster head, average energy dissipation over varying network areas with HEED and LEACH-C.

• Journal of IKEEE
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• v.11 no.4
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• pp.187-192
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• 2007

Since wireless sensor networks (WSN) have relatively narrow bandwidth and have limited memory space. Mosaic by inlaying images transmitted by adjacent sensors can provide wider field of view and smaller storage memory. Most WSN are used for surveillance purpose, image acquisition period should be sufficiently short, so that mosaic algorithm has to be run in real time. Proposed algorithm is derived by using the fact that position of sensor nodes are fixed and known. Transformation matrix can be calculated by using distance between sensor nodes and distance between sensor nodes and predefined object. Simulation result shows that proposed algorithm provides very short processing time whereas it preserves image quality.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.19-27
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• 1991

A new bandwidth reduction algorithm is developed by combining the two-step approach and the frontal ordering scheme. In the two-step approach, finite elements are numbered first, followed by nodal numbering based on the graph theory. The concept of wave front is incorporated into it to control the cardinality of the set of adjacent nodes and the bandwidth to be achieved. They are controlled systematically by rational selection of next candidates with the purpose of getting the smaller bandwidth efficiently. Eighteen meshes are renumbered and the results are compared with those of well-known algorithms. The results demonstrate the efficiency and the reliability of the proposed algorithm.