• Earthquakes and Structures
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• v.10 no.5
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• pp.1233-1251
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• 2016

In this paper, it is aimed to determine the stochastic response of a suspension bridge subjected to spatially varying ground motions considering the geometric nonlinearity. Bosphorus Suspension Bridge built in Turkey and connects Europe to Asia in Istanbul is selected as a numerical example. The spatial variability of the ground motion is considered with the incoherence, wave-passage and site-response effects. The importance of site-response effect which arises from the difference in the local soil conditions at different support points of the structure is also investigated. At the end of the study, mean of the maximum and variance response values obtained from the spatially varying ground motions are compared with those of the specialised cases of the ground motion model. It is seen that each component of the spatially varying ground motion model has important effects on the dynamic behaviour of the bridge. The response values obtained from the general excitation case, which also includes the site-response effect causes larger response values than those of the homogeneous soil condition cases. The variance values calculated for the general excitation case are dominated by dynamic component at the deck and Asian side tower. The response values obtained for the site-response effect alone are larger than the response values obtained for the incoherence and wave-passage effects, separately. It can be concluded that suspension bridges are sensitive to the spatial variability of ground motion. Therefore, the incoherence, the wave-passage and especially the site-response effects should be considered in the stochastic analysis of this type of engineering structures.

• Computational Structural Engineering
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• v.8 no.3
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• pp.103-111
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• 1995

Evaluating nonlinear response of a MDOF system under dynamic stochastic loads such as seismic excitation usually requires excessive computational efforts. To alleviate this computational difficulty, an approximation is developed in which the MDOF inelastic system is replaced by a simple nonlinear equivalent system(ENS).Me ENS retains the most important properties of the original system such as dynamic characteristics of the first two modes and the global yielding behavior of the MDOF system. The system response is described by the maximum global(building) and local(interstory) drifts. The equivalency is achieved by two response scaling factors, a global response scaling factor R/sub G/, and a local response scaling factor R/sub L/, applied to the responses of the ENS to match those of the original MDOF system. These response scaling factors are obtained as functions of ductility and mass participation factors of the first two modes of structures by extensive regression analyses based on results of responses of the MDOF system and the ENS to actual ground accelerations recorded in past earthquakes. To develop the ENS with two response scaling factors, Special Moment Resisting Steel Frames are considered. Then, these response scaling factors are applied to the response of ENS to obtain the nonlinear response of MDOF system.

• Korean Journal of Head & Neck Oncology
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• v.6 no.1
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• pp.11-23
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• 1990

Systemic chemotherapy is usually regarded as the standard treatment for palliation in patients with recurrent or metastatic cancer who have failed the definite local treatment with surgery and/or radiotherapy. Recently, with the introduction of more active chemotherapeutic agents and combinations, systemic chemotherapy is being increasingly used before or after local therapy in patients with previously untreated locally advanced head and neck cancer. The most active agents for the head and neck caner are methotrexate, 5-fluorouracil (5-FU), cisplatin and bleomycin. The overall response rates to each of these four drugs are 15-30% expecially when used as first line therapy. But most of these responses are partial with a mean duration of 3-5 months. Various combinations with methotrexate, 5-FU, cisplatin, and bleomycin have been tried with overall response rates of 50-90%, and 10-20% of complete responses. The introduction of chemotherapy prior to local therapy, induction chemotherapy, has been investigated with improved survivals in patients with complete response, especially pathologic, though improvement in overall survival has not been proved yet after the induction chemotherapy. Other therapeutic modalities, such as 'Sandwich' chemotherapy between surgery and radiotherapy, concomittent chemo-radiotherapy and post local treatment adjuvant chemotherapy have been pursued with some hopeful results but these trials should be compared with prospective randomized Phase III trials. To increase the response rates and enhance the survival, important work still remains; 1. Identification of better prognostic factors, 2. Improvement in staging, 3. Development of more active and safter chemotherapeutic agents, 4. Identification of the proper sequence for the addition of chemotherapy to multimodality treatment, and 5. Testing the value of such chemotherapy in locally advanced cancer patients.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.5
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• pp.39-46
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• 2009

The purpose of this study is to compare and analyze the organizations for responses in disaster fields to cope with large-scaled disasters including Emergency Management Agency, Emergency Response Unit, Emergency Support Center, and Field Command Center (Field Command Office). According to the results of the analysis, the problems of the organizations for responses in local disaster fields are; 1) the scopes of roles among the organizations for responses in disaster fields are ambiguous, 2) the structures of the organizations for responses in disasters are different each other, 3) the integrated management functions among the organizations for responses in disasters are overlapped, and 4) the one who assumes the integrated command is not defined. In order to improve the problems, first, the range of working of each organization for responses in local disaster fields should be definitely established and an agreement in services among the organizations should be settled in advance. Second, similar designs in the structure among the organizations for responses in disasters are necessary for amicable communication. Third, the works for integration and management for each organization for responses should be apportioned. Fourth, the organization in charge and the one who assumes the integrated command for each type of disasters should be appointed in advance for rapid decision-making.

• Journal of the Korean Regional Science Association
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• v.12 no.2
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• pp.79-97
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• 1996

Local dispute resolution has evolved in response to the need for effective ways to cope with the increasing numbers and types of local disputes. Where resources are limited, where the activities of individeuals or communities affect other individuals or communities, and where interests deviate or compete, disputes are likely to emerge. Efforts to resolve local disputes vary in their particulars but generally have certain elements in common. Therefore, this study focuses upon the fundamental directions and strategies for resolving local disputes. More specifically, the purpose of this study is to examine the causes of local disputes, to suggest fundamental directions for resolving local disputes, and then to explore the strategies for resovling local disputes. In the face of rising local disputes, planners need to become more aware of the possibilities for consensual dispute than one potential path to consensus. In spite of this variability, desirable strategies in local dispute resoultion processes can be identified.

• Communications for Statistical Applications and Methods
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• v.9 no.3
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• pp.743-752
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• 2002

The estimation of the response curve is the important problem in the quantal bioassay. When we estimate the response curve, we determine the design points in advance of the experiment. Then naturally we have a question of which design would be optimal. As a response curve estimator, locally weighted quasi-likelihood estimator has several more appealing features than the traditional nonparametric estimators. The optimal design density for the locally weighted quasi-likelihood estimator is derived and its ability both in theoretical and in empirical point of view are investigated.

• Journal of Radiation Protection and Research
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• v.41 no.3
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• pp.301-309
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• 2016

Background: A contamination screening process for the local population in radiation emergencies is discussed. Materials and Methods: We present an overview of the relevant Korean governmental regulations that underpin the development of an effective response system. Moreover, case studies of foreign countries responding to mass casualties are presented, and indicate that responses should be able to handle a large demand for contamination screening of the local public as well as screening of the immediate victims of the incident. Results and Discussion: We propose operating procedures for an off-site contamination screening post operated by the local government for members of the public who have not been directly harmed in the accident. In order to devise screening categories, sorting strategies assessing contamination and exposure are discussed, as well as a psychological response system. Conclusion: This study will lead to the effective operation of contamination screening clinics if an accident occurs. Furthermore, the role of contamination screening clinics in the overall context of the radiation emergency treatment system should be clearly established.

• Smart Structures and Systems
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• v.4 no.6
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• pp.795-807
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• 2008

A challenging problem in structural damage detection based on vibration data is the requirement of a large number of sensors and the numerical difficulty in obtaining reasonably accurate results when the system is large. To address this issue, the substructure identification approach may be used. Due to practical limitations, the response data are not available at all degrees of freedom of the structure and the external excitations may not be measured (or available). In this paper, an adaptive damage tracking technique, referred to as the sequential nonlinear least-square estimation with unknown inputs and unknown outputs (SNLSE-UI-UO) and the sub-structure approach are used to identify damages at critical locations (hot spots) of the complex structure. In our approach, only a limited number of response data are needed and the external excitations may not be measured, thus significantly reducing the number of sensors required and the corresponding computational efforts. The accuracy of the proposed approach is illustrated using a long-span truss with finite-element formulation and an 8-story nonlinear base-isolated building. Simulation results demonstrate that the proposed approach is capable of tracking the local structural damages without the global information of the entire structure, and it is suitable for local structural health monitoring.

• Radiation Oncology Journal
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• v.7 no.2
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• pp.213-225
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• 1989

An analysis has been made of two hundred seven patients who were treated at the department of Radiation Oncology of Korea University Hospital for lung cancer from January 1981 through December 1986. There were 137 patients of nonsmall cell carcinoma (137/207, 66%), 26 patients of small cell carcinoma (26/207, 12.5%) and 44 patients of unproven histology. By aims of treatment, there were 104 patients (104/207, 50%) treated for cure, 89 patients (89/207, 42.9%) for palliation and 14 patients treated postoperatively. In 22 out of 207 patients, chemotherapy was done with radiotherapy, 12 of which were patients with small cell carcinoma. Stage II patients were 49 (49/207, 23.6%), stage III patients were 157 (157/207, 75.8%) and one patient had an occult cancer The tumor was initial Iy measured by CAT scan and chest X-rays in the 165 (165/207, 79.7%) patients, among which 117 patients had tumor diameter more than 5cm and 48 patients less than 5cm. Radiation therapy was given with Cobalt 60 teletherapy unit and the treatment volume encompassed primary tumor and the mediastinum. For curative aim, daily tumor dose of 180 cGy was given up to the range of 5,400~6,120cGy/30~34F/6~7 week period and for palliative aim, daily tumor dose of 300 cGy was given up to the range of 3,600~4,500 cGy/12~15F/2~3 week period. Postoperatively, mediastinum was treated for total dose of 5,040 cGy/28F/5.5 week period. 123 patients (123/207, 59%) were followed up after completion of radiotherapy for 14 months to 7 years. Local tumor response to the irradiation was measured by chest X-ray taken at one month follow up and was evaluated for response rate, if they were regressed more than 50% or less than 50% of the initial tumor size. The treatment results were as follows; 1. The median survival time was 8.5 months and survival rates for 1 year, 2 year and 5 year was 25%, 3.5% and 1% of nonsmall cell lung ca of 74 evaluable patients. 2. More than 50% of local tumor response rate was obtained in about half of overall cases; 90.5% for small cell ca, 50% for squamous cell ca, 25% for adenoca and 57% for large cell ca. 3. Response rate more than 50% was seen in the 50% of the patient group with tumor diameter more than 5cm and in the 55% of those with tumor diameter less than 5cm. 4. By total raidation dose given, patient group which was given 5,400~6,120 cGy equivalent dose or higher showed tumor response rate more than 50% in 53% of the patients, whereas the group with dose less than 5,400cGy equivalent, in 25% of the patients. 5. Survival rate for 6 month, 1 year and 2 year was compared between the group of local tumor response rate more than 50% vs. group with response rate less than 50%; 74% vs. 43%, 33% vs, 23%, 10% vs. 1%, respectively. 6. Local failure was seen in 21%(44/207) of the patients, which occured mostly within 15 months after completion of radiation therapy. Distant metastases were seen in 49.7%(103/207) of the patients, of which 43 cases were found before initiation of radiotherapy. The most common metastatic sites were bone and brain. In this sutdy, 1 year,2 year and S year survival rates were somewhat poor compared to the other studies. It mainly seems to be due to the poor general status of the patients and the far-advanced stage of the disease. In nonsmall cell cancer patients who had limited local disease and had small primary tumor size, we observed better local response. In addition, dose higher than 6,000 cGy group showed better tumor control than lower dose group. Survival rate was better for the local control group. For imporvement of local control of the lung cancer and hence, the survival of the patients with lung cancer, proper radical radiotherapy with high dose for localized disease is needed. New modality of treatment such as high LET beam in radiation therapy or drugs for the advanced disease as well as early diagnosis is also needed.

• Journal of applied mathematics & informatics
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• v.41 no.6
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• pp.1341-1364
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• 2023

This article introduces a method for estimating the conditional hazard function of a real-valued response variable based on a functional variable. The method uses local linear estimation of the conditional density and cumulative distribution function and is applied to a functional stationary ergodic process where the explanatory variable is in a semi-metric space and the response is a scalar value. We also examine the uniform almost complete convergence of this estimation technique.