• The Korean Journal of Applied Statistics
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• v.27 no.7
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• pp.1115-1123
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• 2014

The main purpose of phase I clinical trials is to estimate the Maximum Tolerated Dose (MTD), which minimizes side effect and assures safety of a new drug by evaluating the toxicity at each dose-level. The conventional MTD estimation methods is Standard method (Storer, 1989; Korn et al., 1994), Accelerated Titration Designs (Simon et al., 1997) and DM method (Dixon and Mood, 1948) etc. In this paper, MTD estimation method with de-escalation is suggested phase I clinical trials. The proposed MTD estimation method is compared to Accelerated Titration Designs, SM3 without de-escalation method and SM3 with de-escalation method using a Monte Carlo simulation.

• Korean Journal of Construction Engineering and Management
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• v.20 no.3
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• pp.3-11
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• 2019

The construction of a facility is an act whereby infrastructure such as roads and railways and other facilities such as housing and office spaces are constructed, and due to the characteristics of the relevant industry where such construction is carried out in a custom order method, it requires a long period of time mostly. While the construction is carried out over a long period of time, fluctuations in the price of raw materials required for the construction occur. Therefore, the cost of the construction also fluctuates inevitably. The fluctuation of the construction cost meshes closely with the profit of a constructor and the efficiency of government spending. Therefore, it is necessary to maintain the construction cost at a reasonable level by adjusting the construction cost rationally in order to secure the required construction quality and spend the budget efficiently. The buffer system for solving such problem is the contract amount adjustment system by fluctuations in prices (Escalation/De-Escalation). In this study, the method combining the escalation method based on the item adjustment method was suggested for an efficient contract amount adjustment method. In addition, it is proposed that there be an investigation and codification of matters not applied to government acts and regulations on contracts related to the adjustment of fluctuations in prices legally.

• Journal of KIISE:Databases
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• v.28 no.4
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• pp.742-757
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• 2001

Since database management systems(DBMSS) have limited lock resources, transactions requesting locks beyond the limit mutt be aborted. In the worst carte, if such transactions are aborted repeatedly, the DBMS can become paralyzed, i.e., transaction execute but cannot commit. Lock escalation is considered a solution to this problem. However, existing lock escalation methods do not provide a complete solution. In this paper, we prognose a new lock escalation method, adaptive lock escalation, that selves most of the problems. First, we propose a general model for lock escalation and present the concept of the unescalatable look, which is the major cause making the transactions to abort. Second, we propose the notions of semi lock escalation, lock blocking, and selective relief as the mechanisms to control the number of unescalatable locks. We then propose the adaptive lock escalation method using these notions. Adaptive lock escalation reduces needless aborts and guarantees that the DBMS is not paralyzed under excessive lock requests. It also allows graceful degradation of performance under those circumstances. Third, through extensive simulation, we show that adaptive lock escalation outperforms existing lock escalation methods. The results show that, compared to the existing methods, adaptive lock escalation reduces the number of aborts and the average response time, and increases the throughput to a great extent. Especially, it is shown that the number of concurrent transactions can be increased more than 16 ~256 fold. The contribution of this paper is significant in that it has formally analysed the role of lock escalation in lock resource management and identified the detailed underlying mechanisms. Existing lock escalation methods rely on users or system administrator to handle the problems of excessive lock requests. In contrast, adaptive lock escalation releases the users of this responsibility by providing graceful degradation and preventing system paralysis through automatic control of unescalatable locks Thus adaptive lock escalation can contribute to developing self-tuning: DBMSS that draw a lot of attention these days.

• Korean Journal of Construction Engineering and Management
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• v.12 no.4
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• pp.70-78
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• 2011

In case of long time progressive construction work, we need contract sum adjustment due to escalation for a period of works and the process of applying, consistent and obvious criterion is required. In this study, it were attempted to figure out problem and study this rational improvement by giving examples based on core activities of escalation adjustment. Based on literature study and legal system analysis, we classified processes of contract sum adjustment for escalation and defined 20 core activities for each process. From this measured variable, we carried out case study by giving 37 examples of escalation. As a result of case study, problems of each process was found and we suggested rational improvement. As this study, providers will be able to waste budget and the other will be given smooth escalation adjustment.

• Journal of the Korea Institute of Building Construction
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• v.12 no.1
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• pp.108-114
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• 2012

Escalation method examining the changes in price index has been widely utilized in public construction projects. The previous escalation method determined estimated changes in price based on the average unit price of contract items over a period of time. In relation to this method, the issue has been raised that the fluctuation rates of previous method show different trends compared with other related price indices, as the influence of the small group of contract items with large unit prices overwhelms the others. This research suggested an improved escalation method which estimates the fluctuation rate by examining the changes in CCI (construction cost index) and applies it to the total amount or the partial amount deducted for labor cost in price escalation for previous bid price method. To verify the improvement, a case study is conducted on an educational facility, and the fluctuation rate was estimated in two different base periods (short term, long term). The results over the long term showed similar tendencies to those of related price indices, as well as significant differences in fluctuation rates compared to those of the previous method.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.11a
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• pp.117-120
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• 2005

The business market of architecture has got a system that controls a deposit according to the price function. This system is written on a law of contract about countries. So the main body of construction has to make a reasonable contract. This study is written about a rate of numerical index on controling a deposit. We tried to fine problems and solutions of labor expenses, instrument costs and material costs which is so big and changable on the construction market Labor expenses are expressed according to the rate of construction scale between direct and indirect cost that applies ability of works. Instrument costs are expressed according to an output method of a unit price annually and a weight allowance of local instrument conditions and use frequence. The last material costs expressed according to a local weight allowance make a decision of the material cost index. They applies locally relative index more than absolute one on what uses the price rate of producers and importations. This solutions are not enough to apply to the real market, so it needs to exam and to be on the market after a feasibility study.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.1063-1070
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• 2017

This paper presents a method for forecasting future uranium prices that is used as input data to calculate the uranium cost, which is a rational key cost driver of the nuclear fuel cycle cost. In other words, the statistical autoregressive integrated moving average (ARIMA) model and existing engineering cost estimation method, the so-called escalation rate model, were subjected to a comparative analysis. When the uranium price was forecasted in 2015, the margin of error of the ARIMA model forecasting was calculated and found to be 5.4%, whereas the escalation rate model was found to have a margin of error of 7.32%. Thus, it was verified that the ARIMA model is more suitable than the escalation rate model at decreasing uncertainty in nuclear fuel cycle cost calculation.

• Korean Journal of Construction Engineering and Management
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• v.5 no.6 s.22
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• pp.203-211
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• 2004

This study is the results to survey on the problems and improvable Policies for current escalation system in construction contracts, through a Delphi survey to experts. From the survey results, it is desirable to decide the fluctuation rate of construction cost, which is the requirement of escalation clause, on the basis of inflation rate or construction cost index. The desirable price fluctuation rate is proposed as a $3\%$ level. However, it is difficult for construction companies to cope with the sudden increase of material price in advance, arising from short-term shock factors such as exchange rate and international raw material's price. Accordingly escalation system for specified materials, as an exceptional mode, should be introduced. As a method to calculate the fluctuation rate, ARCA(adjustment rate for the categories of articles) is more desirable than ARI(adjustment rate for an index), because the ARCA can be more reflected the characteristics of each construction work.To rationalize the ARI method, it is needed to announce the wage index, material index and machinery expense index via detailed classification by construction types. Also, it is desirable to prescribe the bidding date as a starting date of the price change, rather than contact signing date. considering the price change can happen since the biddiilg stage.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.540-545
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• 2008

The purpose of this study is to suggest problems and improving plan of process of calculating escalation rate of the Historical Cost by price fluctuation. In order to implement this research, we analyzed problems by calculating the rate of price fluctuation with Historical Cost and measurement applying method making on-site with historical cost data were included as samples and suggested improving plan to the adjustment of contract cost. The results of research according to this are same as followings:1) Of all construction details, it is more appropriate to calculate price fluctuation by applying measurement method to the contents of historical cost unit. 2) To avoid confusion in calculating method, it was indicated that amendment in part should be achieved in order to calculate by measuring the part of calculating escalation rate of Historical Cost at related law and regulation.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.21-31
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• 2020

This study investigates the dynamic effects of economic development, international cooperation, electricity consumption, and political risk on the escalation of CO₂ emission in Vietnam. We adopted autoregressive distributed lag model and Granger causality method to examine the interaction between CO₂ and various economic and political factors, including foreign direct investment, trade openness, economic growth, manufacture, electricity consumption, and political risk in Vietnam since the economic revolution in 1986. The findings reflect opposite influence between these factors and the level of CO₂ in the intermediate and long-term durations. Accordingly, foreign direct investment and CO₂ emission have a bidirectional relationship, in which foreign direct investment accelerates short-term CO₂ emission, but reduces it in the long run through an interactive mechanism. Moreover, economic development increases the volume of CO₂ emission in both short and long run. There was also evidence that political risk has a negative effect on the environment. Overall, the findings confirm lasting negative environmental effects of economic growth, trade liberalization, and increased electricity consumption. These factors, with Granger causality, mutually affect the escalation of CO₂ in Vietnam. In order to control the level of CO₂, more efforts are required to improve administrative transparency, attract high-quality foreign investment, and decouple the environment from economic development.