• Journal of Navigation and Port Research
• /
• v.33 no.7
• /
• pp.469-476
• /
• 2009

Recent collapse of shipping market right after unprecedent surge clearly demonstrates that shipping industry is extremely risky. Due to the volatile movements of the freight rates, investors tend to ask higher rate of return; higher required return reduces the total net present value of the investment project. For several decades, the Discounted Cash Flow(DCF hereafter) analysis has been the most frequently used valuation technique. However, the main problem of the DCF analysis is its assumption that the discount rate would stay the same during the project life. In other words, it usually does not address the decisions that managers have after a project has been accepted. The purpose of this study is investigate a new valuation method of investment: the Real Option Analysis(ROA hereafter) on ship investment. By replacing the existing valuation methods with the new one, the research will present a new perspective on investment with uncertainty. While uncertainty increases risk of investment and consequently discounts the value of it in the traditional feasibility analysis, in the ROA, a new valuation method which will be addressed in the research, uncertainty means some additional value of flexibility so that the tool can help investors produce more accurate decisions. Contrary to the DCF analysis, the ROA takes managerial flexibilities into account. In reality, capital budgeting and project management is typically dynamic, rather than static in nature. The ROA finds and assesses the values of managerial flexibilities or real options in the investments. The main structures of the research will be as follows: (1) overview of the ship investment project, (2) evaluation of the project by the Net Present Value analysis, (3) evaluation of the same project by the Real Option Analysis, (4) comparision of the two techniques.

• Tuberculosis and Respiratory Diseases
• /
• v.40 no.6
• /
• pp.742-746
• /
• 1993

Recent literature reveals that pulmonary embolism secondary of pulmonary tumor embolism are dyspnea, hemoptysis, pulmonary hypertension, and circulatory collapse. We experienced a case of pulmonary embolism secondary to hepatocelluar cancer in 53-year-old man. From 2 months before admission, he began to experience cough and mild shortness of breath. Within a few days these symptoms progressed to near total incapacity. Pulmonary embolism was confirmed by angiography and the diagnosis of hepatocellular cancer was estabillished by abdomen CT and $\alpha$-FP(21,000 ng/ml). There was no evidence of intravascular cogulation elsewhere in deep vein of the extremities or risk factors of deep vein thrombosis. Thus we consider that pulmonary embolism in this patients is related to hepatocellular cancer rather than deep vein thrombosis. Therefore we report the first case which hepatocellular cancer initially presented as pulmonary embolism in Korean literature.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.21 no.5
• /
• pp.135-140
• /
• 2021

In this paper, we propose an on-line mechanism that simultaneously detects cracks and profiling pavement blocks to detect the displacement of ground surface adjacent to the excavation in the urban area. The proposed method utilizes a 2D laser to profile the information about pavement blocks including the depth and distance among them. In particular, it is designed to enable the detection of cracks and portholes at runtime. For the experiment, real data was collected through Gocator, and trainng was carried out using Faster R-CNN. The performance evaluation shows that our detection precision and recall are more than 90% and the pavement blocks are profiled at the same time. Our proposed mechanism can be used for monitoring management to quantitatively detect the level of excavation risk before a large-scale ground collapse occurs.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.4
• /
• pp.653-658
• /
• 2021

Convergence of ICT technology and various industry have been proliferated. It makes human life affluent pulling existing industry paradigm down while they do not realize. Also, it impacts on personal life and becomes a driving force which strengthen the state level and its competitiveness. Complexity is increasing, knowledge is expanding and ICT technology is evolving in the present industrial society. Thus, new business model is being created, established business without competitiveness is eliminated and new ecosystem is constructed for industry change or creation. The new business and its competitive order driving in current convergence environment is apt to be exposed to uncertainty risk. These changes promote the collapse of existing industry or create new business models. There are digital transformation and ICT convergence in the center of the changes. The change of society and industry caused by this phenomenon will be analyzed. Also, development direction, strategy and execution method for securing industry competitiveness of ICT convergence will be researched.

• Archives of Craniofacial Surgery
• /
• v.22 no.6
• /
• pp.296-302
• /
• 2021

Background: The reconstruction of large full-thickness alar defects requires complex surgical procedures that are usually performed in two stages, with concomitant disadvantages in terms of patient trauma, surgical risk, and cost. This study presents a functional folded nasolabial island flap (FNIF) that can be used to repair large-sized full-thickness alar defects in a straightforward manner. Methods: This retrospective study included seven patients who received a FNIF for a full-thickness alar defect between January 2007 and December 2020. The FNIF is different from the conventional nasolabial flap in that it is folded and twisted to achieve nostril reconstruction with a satisfactory three-dimensional mucosal lining in a single stage. The cosmetic and functional results of FNIF were evaluated by both patients and physicians. Results: The age ranged from 51 to 82 years (mean, 65.6 years). The causes of the defects were squamous cell carcinoma, basal cell carcinoma, and trigeminal trophic syndrome. The nostril lining did not collapse, there was no hypertrophic scarring, and air movement through the nostrils on the flap side was normal. Overall, FNIF produced excellent aesthetic and functional outcomes, with minimal patient discomfort. There were no postoperative complications. Conclusion: Compared with existing reconstruction methods for large full-thickness alar defects, FNIF can easily achieve aesthetic and functional success in a single-stage procedure. It provides satisfactory results for both the patient and the surgeon.

• Earthquakes and Structures
• /
• v.22 no.2
• /
• pp.169-184
• /
• 2022

The importance of seismicity in developing countries and the strengthening of buildings is a topic of major importance. Therefore, the study of several solutions with the development of new technologies is of great importance to investigate the damage on retrofitted structures by using probabilistic methods. The Federal Emergency Management Agency considers three types of performance levels by considering different scenarios, intensity and duration. The selection and scaling of ground motions mainly depends on the aim of the study. Intensity-based assessments are the most common and compute the response of buildings for a specified seismic intensity. Assessments based on scenarios estimate the response of buildings to different earthquake scenarios. A risk-based assessment is considered as one of the most effective. This research represents a practical method for developing countries where exists many active faults, tall buildings and lack of good implementable approaches. Therefore, to achieve the main goal, two high-rise steel buildings have been modeled and assessed. The contribution of buckling-restrained braces in the elastic design of both buildings is firstly verified. In the nonlinear static range, both buildings presented repairable damage at the central top part and some life safety hinges at the bottom. The nonlinear incremental dynamic analysis was applied by 15 representative/scaled accelerograms to obtain levels of performance and fragility curves. The results shown that by using probabilistic methods, it is possible to estimate the probability of collapse of retrofitted buildings by buckling-restrained braces and tuned mass dampers, which are practical retrofitting options to protect existing structures against earthquakes.

• The Journal of Engineering Geology
• /
• v.31 no.4
• /
• pp.533-540
• /
• 2021

Gravity field analysis and density modeling were performed to evaluate the internal state of the rock mass, which is the cause of cut slope collapse. The shape of the weathered zone and the depth of basement could be confirmed from the complete Bouguer anomaly and density model. The basement depth at the center of the cut slope calculated using the Euler deconvolution inverse method is 30 m, which is about 10 m deeper than the surrounding area. In addition, the depth of basement and the thickness of the weathered zone are similar to the boundary between low resistivity and high resistivity in dipole-dipole survey. From the study results, gravity field analysis and density modeling recognizes the internal state of the rock slope and can be used for slope safety analysis, and is particularly suitable as a method to determine the shape of weathered zones in interpreting the safety of cut slopes

• Structural Monitoring and Maintenance
• /
• v.10 no.1
• /
• pp.87-105
• /
• 2023

Seismic regulations have been updated from time to time to accommodate an increase in seismic hazards. Comparison of seismic fragility of the existing bridges in Indonesia from different historical periods since the era before 1990 will be the basis for seismic assessment of the bridge stock in Indonesia, most of which are located in earthquake-prone areas, especially those built many years ago with outdated regulations. In this study, seismic fragility curves were developed using incremental non-linear time history analysis and more holistically according to the actual strength of concrete and steel material in Indonesia to determine the uncertainty factor of structural capacity, βc. From the research that has been carried out, based on the current seismic load in SNI 2833:2016/Seismic Map 2017 (7% probability of exceedance in 75 years), the performance level of the bridge in the era before SNI 2833:2016 was Operational-Life Safety whereas the performance level of the bridge designed with SNI 2833:2016 was Elastic - Operational. The potential for more severe damage occurs in greater earthquake intensity. Collapse condition occurs at As = F_PGA x PGA value of bridge Era I = 0.93 g; Era II = 1.03 g; Era III = 1.22 g; Era IV = 1.54 g. Furthermore, the fragility analysis was also developed with geometric variations in the same bridge class to see the effect of these variations on the fragility, which is the basis for making bridge risk maps in Indonesia.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.66 no.1
• /
• pp.39-48
• /
• 2024

Plastic greenhouses are simple structures consisting of lightweight materials such as steel pipes and polyvinyl chloride. However, serious damage occurs due to heavy winds and typhoon every year. To prevent a collapse of structural members, the Ministry of Agriculture and Rural Development has distributed plans and specifications for disaster-resistant standards. Despite these efforts, more than 50% of greenhouses still do not satisfy the disaster-resistant standards. Among the greenhouses that do not meet these standards, 85% are single-span greenhouses proposed 20 years ago. Consequently, there is a need to evaluate the safety of wind loads for the single-span greenhouse. Unfortunately, there are no design specifications for the greenhouses under wind loads. Therefore, a Korean design standard (KDS) has been utilized. KDS is defined with reference to wind speeds occurring once every 500 years, raising concerns about potential overdesign when considering the durability of plastic greenhouses. To address this, the modified wind load, considering the durability of the plastic greenhouse, was calculated, and a safety evaluation was conducted for sigle G-type plastic greenhouse. It was observed that the moment acting on the windward surface was substantial, and there was a risk of the foundation being pulled out if the basic wind speed exceeded 32 m/s. In terms of the combination strength ratio, it was less than 1.0 only on the leeward side when the basic wind speed was 24 m/s and 26 m/s. However, in all other cases, it exceeded 1.0, indicating an unsafe condition and highlighting the necessity for reinforcement.

• Earthquakes and Structures
• /
• v.26 no.3
• /
• pp.203-218
• /
• 2024

Beam-column joints in the frame structure are at high risk of brittle shear failure which would lead to significant residual deformation and even the collapse of the structure during an earthquake. In order to improve the damage issue and enhance the recoverability of the beam-column joints, a sector lead rubber damper (SLRD) has been developed. The SLRD can increase the bearing capacity and energy dissipation capacity, and also demonstrating recoverability of seismic performance following cyclic loading. In this paper, the hysteretic behavior of SLRD was experimentally investigated in terms of the regular hysteretic behavior, large deformation behavior and fatigue behavior. Furthermore, a parametric analysis was performed to study the influence of the primary design parameters on the hysteretic behavior of SLRD. The results show that SLRD resist the exerted loading through the shear capacity of both rubber parts coupled with the lead cores in the pre-yielding stage of lead cores. In the post-yielding phase, it is only the rubber parts of the SLRD that provide the shear capacity while the lead cores primarily dissipate the energy through shear deformation. The SLRD possesses a robust capacity for large deformation and can sustain hysteretic behavior when subjected to a loading rotation angle of 1/7 (equivalent to 200% shear strain of the rubber component). Furthermore, it demonstrates excellent fatigue resistance, with a degradation of critical behavior indices by no more than 15% in comparison to initial values even after 30 cycles. As for the designing practice of SLRD, it is recommended to adopt the double lead core scheme, along with a rubber material having the lowest possible shear modulus while meeting the desired bearing capacity and a thickness ratio of 0.4 to 0.5 for the thin steel plate.