• Journal of Ship and Ocean Technology
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• v.3 no.1
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• pp.27-41
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• 1999

The objective of the paper is to study the impact of changing the traditional hull design of bulk carriers by providing them with a double hull while keeping the same deadweight. It is demonstrated that by introducing the double hull the structural reliability is increased throughout the entire life and also the extend of the needed repair is reduced. The results are obtained with recently developed mathematical tools for the reliability assessment of ship hulls subjected to the existence of multiple cracks both in the stiffeners and in the plating and it models the crack growth process. The effect of corrosion is represented as time dependent. The long-term stress range acting on the elements is defined as a function of the local transverse pressure of the internal cargo and outside sea water combined with the stresses resulting from the longitudinal bending of the hull, which is a combined with the stresses resulting from the longitudinal bending of the hull, which is a combineation of horizontal and vertical bending moments. The effect of maintenance actions is modelled as a stochastic process. The results show that a different design of the midship section improves the structural safety and also the economy with respect to structural repair of bulk carriers.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.929-936
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• 2022

In the U.S., the state, local, tribe, and territorial governments seek funding from the federal government through the Public Assistance program to carry out these recovery works. In this paper historic public assistance data between 1998 and 2021 have been analyzed to derive several insights such as: types of disasters causing the most damage, states requiring more support, net present value of the federal expense etc. This paper has found that the states requiring more support from the federal government are not always the states suffering the maximum losses from the disasters. It has also found that the net present value of the federal expense between 1998 and 2020 to restore, repair, reconstruct, or replace disaster damaged roads and bridges across the U.S. is $15 billion in 2021 values. Moreover, this paper has tested the correlation between the states' public assistance funds requirements and the existing condition and performance of roads and bridges as revealed by the American Society of Civil Engineer's infrastructure grade card. It has found a weak correlation between these two. The outcomes of this paper can be used by the decision makers to analyze the viability of any possible alternative to the exiting public assistance program. The insights can also help in better decision making in pre-disaster preparation and post-disaster funds allocation.

• Korean Journal of Head & Neck Oncology
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• v.11 no.1
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• pp.47-55
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• 1995

A large lateral facial defects especially a through and through defect of the cheek remains as challenging field of reconstruction for the head and neck surgeons. Closure of these wounds is technically troublesome due to the magnitude and location of the soft tissue and skin defect, functional and aesthetic consideration. optimal cancer surveillance, and desire for good nourishment. Most traditional methods dealing with these defects, including split-thickness skin graft, local and regional flaps as well as musculocutaneous flaps have their limitations. We applied four different methods for these reconstruction in four cases. We utilized temporal muscle flap, forearm free flap and secondary healing for repair of mucosal defects, and medial base cervicopectoral flap, pectoralis major myocutaneous flap and cervicofacial flap for the reconstruction of external skin defects. In one case, both sides were reconstructed with single forearm free flap. In our experiences, secondary healing could be one of the useful method for mucosal repair in the defect between upper and lower gingivobuccal sulcus. However, forearm free flap was thought to be more ideal for the cases with mandibulectomy. For the external repair, the regional skin flap was considered to be superior to pectoralis major myocutaneous flap or forearm free flap especially on color matching.

• Journal of the Korea Society for Simulation
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• v.15 no.3
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• pp.79-86
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• 2006

This paper proposes a new protocol to enhance the routing performance and applies our proposal to AODV (Ad hoc On-demand Distance Vector routing) protocol, which is a typical on-demand routing protocol in MANET. In general, when a route repair procedure is performed due to the transfer or failure of a node, the source node re-initiate a route discovery procedure in most routing protocols of MANET. This causes to increase the control traffic overhead largely and degrade the routing performance. The main idea of our study is to provide a methodology that can minimize the control traffic overhead and enhance the performance by initiating a route repair procedure at destination node and utilizing the previous routing information maximumly. To evaluate the performance of the our mechanism, we have performed a series of simulations. The simulations include comparisons with AODV and AODV with local repair. The simulations have been executed under simulation environments taking into account mobility speed and network site. The simulation results show that our proposal overall outperforms the existing protocols.

• Journal of the Korean Society of Radiology
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• v.11 no.4
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• pp.177-181
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• 2017

Dose response curves using absorbed dose to the biological effect are usually available in case of conventional X beam. However, absorbed dose is not consider in treatment planning for carbon beam such as heavy ions. Because the biological effects also depend on other quantities such as the local variation, which is often characterized by the linear energy transfer (LET). So LQ model cannot explain the entire response of fractionated carbon beam irradiation. The variation in LET with penetration depth leads to substantial differences in biological effect of carbon beam. And it is therefore essential in treatment planning to calculate not only the absorbed dose but also the LET to estimate the biological outcome of the radiation of interest. LET variation plays an important role in the fractionated irradiations. It is suggested that consideration of LET is necessary in biophysical model.

• The Journal of Sustainable Design and Educational Environment Research
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• v.17 no.2
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• pp.38-47
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• 2018

In Korea, it is difficult to secure student health and safe educational environment due to the rapid deterioration of many school facilities built in the 70s and 80s in the past. As a result, through the improvement of school facilities, social needs for safe schools from various disasters, accidents, Is increasing. The purpose of this study was to establish a standard for the establishment of the national and school facilities for the mid - to long - term plan for the improvement of the old school facilities, and to propose a framework for mid - to long - term and rational planning that can be used by the national and local government offices. The purpose of this study is to establish a mid - and long - term plan for the improvement of old school facilities. The appropriate repair cycle for the improvement of the school facilities set up in this study can be utilized as a standard for the mid - and long - term planning for improvement of the school facilities in the Ministry of Education and the School of Education. To this end, a standard model, It is possible to roughly estimate the overall improvement in the mid- to long-term facilities at the national and regional levels.

• Journal of Chest Surgery
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• v.57 no.3
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• pp.291-299
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• 2024

Background: Postoperative pain management following minimally invasive repair of pectus excavatum (MIRPE) remains a critical concern due to severe post-procedural pain. Promising results have been reported for cryoanalgesia following MIRPE; however, its invasiveness, single-lung ventilation, and additional instrumentation requirements remain obstacles. Serratus anterior plane block (SAPB) is a regional block technique capable of covering the anterior chest wall at the T2-9 levels, which are affected by MIRPE. We hypothesized that SAPB would be a superior alternative pain control modality that reduces postoperative pain more effectively than conventional methods. Methods: We conducted a retrospective study of patients who underwent MIRPE between March 2022 and August 2023. The efficacy of pain control was compared between group N (conventional pain management, n=24) and group S (SAPB, n=26). Group N received intravenous patient-controlled analgesia (IV-PCA) and subcutaneous local anesthetic infusion. Group S received bilateral continuous SAPB with 0.3% ropivacaine after a bilateral bolus injection of 30 mL of 0.25% ropivacaine with baseline IV-PCA. Pain levels were evaluated using a Visual Analog Scale (VAS) at 1, 3, 6, 12, 24, 48, and 72 hours postoperatively and total intravenous rescue analgesic consumption by morphine milligram equivalents (MME). Results: Mean VAS scores were significantly lower in group S than in group N throughout the 72-hour postoperative period (p<0.01). Group S showed significantly lower MME at postoperative 72 hours (group N: 108.53, group S: 16.61; p<0.01). Conclusion: SAPB improved immediate postoperative pain control in both the resting and dynamic states and reduced opioid consumption compared to conventional management.

• Restorative Dentistry and Endodontics
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• v.24 no.1
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• pp.187-199
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• 1999

Bone remodeling is characterized by the continuing processes of osteoblast-mediated bone formation and osteoclast-mediated bone resorption. Bone metabolism is tightly regulated at the local level by networks of hormones, cytokines, and other factors. In pathological conditions of bone remodeling, including osteoporosis and periodontal diseases, inflammatory cytokines and local mediators are responsible for enhancement of osteoclast resorption and inhibition of repair at the sites of bone resorption. TNF-${\alpha}$ is a pleiotropic hormone with actions on the differentiation, growth, and functional activities of normal and malignant cells from numerous tissues. TNF-${\alpha}$ has been proposed as a local mediator of the control of bone turnover in situations of chronic inflammation, and it has been assumed that the local source of TNF-${\alpha}$ is the monocyte in the adjacent bone marrow or the local circulation. TNF-${\alpha}$ is a potent inducer of bone resorption. TNF-${\alpha}$ is known to induce the activation of apoptotic signaling pathway, which leads to the apoptosis of bone cells. We demonstrated that treatment of murine osteoblastic MC3T3E1 cells with TNF-${\alpha}$ decreases proliferation as well as alkaline phosphatase (ALP) activity in a dose depenent manner. In addition, TNF-${\alpha}$ increases osteoclast-like cell formation in $1{\alpha}$, 25(OH)2D3 or PGE2-treated bone marrow cell culture. When cells were cultured in TNF-${\alpha}$ free ${\alpha}$-MEM, this inhibitory effect of ALP activity was reversible up to 10 ng/ml TNF-${\alpha}$, in contrast, at the 20 ng/ml TNF-${\alpha}$, irreversible. In this concentration, TNF-${\alpha}$ may induce apoptosis in MC3T3E1 cells. In this study, TNF-${\alpha}$ induces apoptosis resulting in chromosomal DNA fragmentation, preceded by JNK/SAPKs and caspase-3 activation. Our present results show that JNK/SAPKs and caspase-3 are activated by TNF-${\alpha}$, suggesting that the JNK/SAPKs and caspase-3 participate in the bone resorption, associated with apoptosis.

• The Korean Journal of Community Living Science
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• v.17 no.4
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• pp.67-80
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• 2006

This study conducted research on the actual state of community-oriented services for elderly rural inhabitants and their desire related to them to develop a local community service network model suitable to the characteristics of rural longevity villages. The research was conducted on 906 elderly people over 65 living in 20 rural longevity villages through questionnaires assessing filming and economy, economic activity, health care, learning and leisure activities as well as asking their wants and needs relative to local community services. As a result, it was found rural elderly people showed a high desire for local community services such as health, transportation and economy activity. In addition, they were mainly cultivating farm products as their economic activity and showed a high demand in the future as well. Most were found to take a walk in the healthcare field and showed a high demand for health examinations, health education, health consulting, hot spring bathing and basking in the woods. Respecting learning, social and leisure activities, they were mostly found to watch TV and do house chores, and showed a high desire for village environment repair, traditional farm music, visiting and tourism. With the above results, it is expected that the desire of rural elderly for such services can be satisfied, and the development of a local community service network model suitable to the characteristic of a local community is recommended.

• Journal of Soil and Groundwater Environment
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• v.16 no.6
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• pp.106-112
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• 2011

This study developed preliminary assessment methodology for priority listing of soil and groundwater contamination sources, considering source characteristics, local environments and risk receptors. Source characteristics were evaluated by scoring relative risk of contamination sources. Local environments were evaluated by scoring annual rainfall, hydraulic conductivity of aquifer, and annual groundwater use. Risk receptors were evaluated by scoring local population, direct distance to surface water, direct distance to drinking-water wells. Scores of each parameter were allocated by analysing distribution of parameter values obtained from government databases. Distributed scores of source characteristics local environments: risk receptors were 12 : 12 : 12. The preliminary assessment scored 0 to 36 for each soil and groundwater sources. Inventory of soil and groundwater sources consisted of 7 categories. This study applied the preliminary assessment methodology to Manan-Gu, Anyang City, Korea. The number of car repair and washing facility was the largest in the contamination source inventory. Petroleum storage facilities showed the highest assessment score. The preliminary assessment methodology also indicated that Anyang-Dong was the priority section among Anyang-Dong, Suksu-Dong, Bakdal-Dong. This study is the first trial for relative ranking soil and groundwater contamination sources by considering source and local characteristics. Therefore, further researches and revision of the preliminary assessment methodology need to be pursued for various applications.