• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6C
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• pp.231-240
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• 2011

Various pile load tests were carried out at Gwangyang district for 10 different piles in order to analyze the characteristcs of steel pile using high strength steel and high driving energy. Pile drivability results showed that PHC piles needed highest total blow count even with the shortest pile length and high strength steel pipe piles showed smallest total blow count eventhough driven to a more hard ground condition with longer pile length. Pile dynamic analysis results showed that for PHC pile and general steel pipe pile the allowable pile design load was decided by the allowable material strength but for high strength steel pipe pile the design load can be decided according to the ground bearing capacity. Static load test and load transfer test results showed that the pile design efficiency could be improved over 80% allowing lesser number of piles necessary for a more economical solution. Set-up effects was analyzed and regression equation for the site ground condition was derived. Bearing capacity was checked with widely used design equation and the limitation of current design method and future technology development on this subject is dicussed in this paper.

• Journal of the Korean GEO-environmental Society
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• v.17 no.12
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• pp.55-64
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• 2016

In this paper bearing capacity and safety margin of shallow foundation on weathered soil ground against shear failure by using current design method of allowable stress design (ASD), load resistance factor design (LRFD) based on reliability analysis and partial safety factor design (PSFD) in Eurocode were estimated and compared to each other. Results of the plate loading test used in construction and design were collected and analysis of probability statistics on soil parameters affecting the bearing capacity of shallow foundation was performed to quantify the uncertainty of them and to investigate the resistance bias factor and covalence of ultimate bearing capacity. For the typical sections of shallow foundation in domestic field as examples, reliability index was obtained by reliability analysis (FORM) and the sensitivity analysis on soil parameters of probability variables was performed to investigate the effect of probability variable on shear failure. From stability analysis for these sections by ASD, LRFD with the target reiability index corresponding to the safety factor used in ASD and PSDF, safety margins were estimated respectively and compared.

• Magazine of the Korean Society of Agricultural Engineers
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• v.25 no.2
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• pp.35-41
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• 1983

This research is mainly to deal with the effects of submergence treatment on the grain yields of two rice plants, local variety, "Akibare" and Tongil line variety, "Milyang 23". The results obtained are summarized as follows. 1. According to the rice products of each plot the grain yield index was smallest in the plot treated at the early heading stage. The index of the next order became smaller in order of late flowering stage, late reduction division stage, milk ripe stage and dough ripe stage etc. The submerged stage at which the damages were smallest was tillering stage. Under the condition of two thirds or one third submerged depth of plant height, few differences in the grain yield index between Milyang 23 and Akibare was found, but except rooting stage, the damages of milyang 23 by whole submergence during growing period were mostly greater than those of Akibare. Especially the grain yield index of early heading stage at which the damages by whole submergence was most serious showed 45 percentage for one day submergence, 31 percentage for 3 days and 0.7 percentage for 7 days in Akibare plots, and 26.7% percentage for one day submergence, 7.9 percentage for 3 days and none for 7 days in Milyang 23 plots. 2. All the factors such as submerged stage, submerged depth and submerged period in this experimental test were highly recognized significance. The factors of the submerged depth and duration influenced on greater damages than the others. According to the difference in grain yield between plots, the larger the submerged depth and duration were, the larger the significant difference appeared. And between the treated levels at other submerged stages except both early tillering stage and most active tillering stage, the significance in the differences in grain yield was recognized, while only the submergence at early heading stage showed the most serious damages. 3. The decreased rate of grain yield for one day submergence at early heading stage indicated that in case of whole submergence of plant height it was 73 percentage in Milyang 23 plot and 55 percentage in Akibare plot, and in the event of two thirds and one third submergences of it, 20 percentage and 10 percentage in both Mulyang 23 and Akibare plots respectively. Therefore, the current criteria for planning project that restricted allowable submergence duration of more than 30cm submerged depth to 24 hours, should be amended not to exceed the submerged depth of 60cm when the duration of more than allowable submerged depth of 30cm will be limited to 24 hours, or within the limits of 12 hour submerged duration for locai variety and of less than 12 hour duration for Tong-illine variety as long as possible in case that submerged depth will be allowed to more than 60cm depth.ore than 60cm depth.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.5
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• pp.552-560
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• 2013

In this paper, an optimization algorithm for the block assembly accuracy control assessment is proposed with consideration for the current block assembly process and accuracy control procedure used in the shipbuilding site. The objective function of the proposed algorithm consists of root mean square error of the distances between design and measured data of the other control points with respect to a specific point of the whole control points. The control points are divided into two groups: points on the control line and the other points. The grouped data are used as criteria for determining the combination of 6 degrees of freedom in the registration process when constituting constraints and calculating objective function. The optimization algorithm is developed by using combination of the sampling method and the point to point relation based modified ICP algorithm which has an allowable error check procedure that makes sure that error between design and measured point is under allowable error. According to the results from the application of the proposed algorithm with the design and measured data of two blocks data which are verified and validated by an expert in the shipbuilding site, it implies that the choice of whole control points as target points for the accuracy calculation shows better results than that of the control points on the control line as target points for the accuracy of the calculation and the best optimized result can be acquired from the accuracy calculation with a fixed point on the control line as the reference point of the registration.

• Journal of Cadastre & Land InformatiX
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• v.49 no.1
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• pp.157-179
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• 2019

The Seoul's 2030 Youth-Housing has been regarded as the only option to procure rental housing sites in downtown Seoul. But its supply did not catch up with the initial expectation, and the criticism that it may disrupt the current zoning system of the city has persisted. Consequently, the 2030 Youth-Housing policy has undergone amendments for six times within the last three years, and the significant changes in its guideline also have been made within the last one year. The study, in this context, tries to figure out the tendencies of those changes made in the guidelines so far by analyzing the aspects of the parcels allowable for Youth-Housing as well as the areas allowable for up-zoning. In the process, the propositional logic is to be adopted to draw the scope of the buildable areas for Youth-Housing. For this, the study refines the raw GIS data, inputs the values for each proposition, and proceeds the logical operation to judge every parcel of the city to discern whether it is eligible for a buildable site and/or for up-zoning for Youth-Housing. It is seen that: 1) the buildable sites rather evenly distribute around the peripheral subway-station areas while more concentrating on the quasi-residential and commercial areas; and 2) the areas eligible for up-zoning have the tendency to concentrate more on quasi-residential areas than others.

• The Journal of the Convergence on Culture Technology
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• v.5 no.1
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• pp.127-137
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• 2019

In this study, I set the allowable range of viewing / copying rights of investigation records on criminal victims and bereaved families in the procedure of investigation. I tried to grasp the contents of the suspect's statement at an early stage and support it in order to cope appropriately Recently, the social consideration of people suffering from crime victims is expanding in fact. The scope of the investigation is set by the lawyer of the suspect in relation to the subordinate statute concerning the investigation and reading of the investigation record. In parallel, it is necessary to apply to the victim's lawyer or bereaved. This is a part that coincides with the purpose of certifying private rights such as browsing of litigation records to the victim and ultimately has a purpose related to the allowable range. Although it is the right to receive the investigation result at each stage, it is not used properly. Especially when distorted investigation progresses, if the suspect is not prosecuted, the victim may be in a state of regret. The important part can be summarized as the question of whether the investigation of the victim's lawyer is allowed to view and access the criminal records. This section has been reviewed with a focus on the current Act and its functional aspects should be emphasized and revised in accordance with the legal environment. These findings will contribute to ensuring victims' rights in the future. It is also used as an important resource in the legislative process, including the revision of the criminal procedure law.

• Journal of the Korean GEO-environmental Society
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• v.12 no.3
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• pp.5-12
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• 2011

In this paper, after studying structural performance for the representative corrugated steel plate used in Korea, we proposed the optimum shape for section of corrugated steel plate considering a width of steel plates that can be produced currently in the factory. Using AISI(1986) in examination for the performance of the corrugated steel plate, we determined the mechanical limit of the optimum sections considering shear force and bending moment of corrugated steel plate and also determined the geometric limit of them considering formability, shapes and ratio between width of steel plate before forming and that after forming. As a result of examination for performance of steel plate applying algorithm for searching optimal sections algorithm developed in this study to the existing representative corrugated steel plate, allowable force and moment of inertia indicated the maximum values at bending radius 76mm and internal bending angle $50^{\circ}$. And as an application result of the optimum design system that used SS490 with 1,550mm of width and 4,700mm of length considering current production situation in Korea, we developed the new section with more than 2 times of structural performance comparing with existing corrugated steel plate.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.3
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• pp.87-99
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• 1982

This study proposes a reliability based design criteria for the R.C. superstructures of highway bridges. Uncertainties associated with the resistance of T or rectangular sections are investigated, and a set of appropriate uncertainties associated with the bridge dead and traffic live loads are proposed by reflecting our level of practice. Major 2nd moment reliability analysis and design theories including both Cornell's MFOSM(Mean First Order 2nd Moment) Methods and Lind-Hasofer's AFOSM(Advanced First Order 2nd Moment) Methods are summarized and compared, and it has been found that Ellingwood's algorithm and an approximate log-normal type reliability formula are well suited for the proposed reliability study. A target reliability index (${\beta}_0=3.5$) is selected as an optimal value considering our practice based on the calibration with the current R.C. bridge design safety provisions. A set of load and resistance factors is derived by the proposed uncertainties and the methods corresponding to the target reliability. Furthermore, a set of nominal safety factors and allowable stresses are proposed for the current W.S.D. design provisions. It may be asserted that the proposed L.R.F.D. reliability based design criteria for the R.C. highway bridges may have to be incorporated into the current R.C. bridge design codes as a design provision corresponding to the U.S.D. provisions of the current R.C. design code.

• The Korean Journal of Air & Space Law and Policy
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• v.31 no.2
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• pp.145-176
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• 2016

Aviation safety can be secured through regulations and policies of various areas and thorough execution of them on the field. Recently, for aviation safety management Korea is making efforts to prevent aviation accidents by taking various measures: such as selecting and promoting major strategic goals for each sector; establishing National Aviation Safety Program, including the Second Basic Plan for Aviation Policy; and improving aviation related legislations. Obstacle limitation surface is to be established and publicly notified to ensure safe take-off and landing as well as aviation safety during the circling of aircraft around airports. This study intends to review current aviation obstacle management system which was designed to make sure that buildings and structures do not exceed the height of obstacle limitation surface and identify its operating problems based on my field experience. Also, in this study, I would like to propose ways to improve the system in legal and regulatory aspects. Nowadays, due to the request of residents in the vicinity of airports, discussions and studies on aviational review are being actively carried out. Also, related ordinance and specific procedures will be established soon. However, in addition to this, I would like to propose the ways to improve shortcomings of current system caused by the lack of regulations and legislations for obstacle management. In order to execute obstacle limitation surface regulation, there has to be limits on constructing new buildings, causing real restriction for the residents living in the vicinity of airports on exercising their property rights. In this sense, it is regarded as a sensitive issue since a number of related civil complaints are filed and swift but accurate decision making is required. According to Aviation Act, currently airport operators are handling this task under the cooperation with local governments. Thus, administrative activities of local governments that have the authority to give permits for installation of buildings and structures are critically important. The law requires to carry out precise surveying of vast area and to report the outcome to the government every five years. However, there can be many problems, such as changes in the number of obstacles due to the error in the survey, or failure to apply for consultation with local governments on the exercise of construction permission. However, there is neither standards for allowable errors, preventive measures, nor penalty for the violation of appropriate procedures. As such, only follow-up measures can be taken. Nevertheless, once construction of a building is completed violating the obstacle limitation surface, practically it is difficult to take any measures, including the elimination of the building, because the owner of the building would have been following legal process for the construction by getting permit from the government. In order to address this problem, I believe penalty provision for the violation of Aviation Act needs to be added. Also, it is required to apply the same standards of allowable error stipulated in Building Act to precise surveying in the aviation field. Hence, I would like to propose the ways to improve current system in an effective manner.

• Journal of the Korean GEO-environmental Society
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• v.19 no.4
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• pp.5-16
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• 2018

In the current study, the engineering behaviour of prebored and precast steel pipe piles was examined from a series of full-scale field measurements by conducting static pile load tests, dynamic pile load tests (EOID and restrike tests) and Class-A and Class-C1 type numerical analysis. The study includes the pile load - settlement relations, allowable pile capacity and shear stress transfer mechanism. Compared to the allowable pile capacity obtained from the static pile load tests, the dynamic pile load tests and the numerical simulation showed surprisingly large variations. Overall among these the restrike tests displayed the best results, however the reliability of the predictions from the numerical analysis was lower than those estimated from the dynamic pile load tests. The allowable pile capacity obtained from the EOID tests and the restrike tests indicated 20.0%-181.0% (avg: 69.3%) and 48.2%-181.1% (avg: 92.1%) of the corresponding measured values from the static pile loading tests, respectively. Furthermore, the computed results from the Class-A type analysis showed the largest scatters (37.1%-210.5%, avg: 121.2%). In the EOID tests, a majority of the external load were carried by the end bearing pile capacity, however, similar skin friction and end bearing capacity in magnitude were mobilised in the restrike tests. The measured end bearing pile capacity from the restrike tests were smaller than was measured from the EOID tests. The present study has revealed that if the impact energy is not sufficient in a restrike test, the end bearing pile capacity most likely will be underestimated. The shear stresses computed from the numerical analysis deviated substantially from the measured pile force distributions. It can be concluded that the engineering behaviour of the pile is heavily affected if a slime layer exists near the pile tip, and that the smaller the stiffness of the slime and the thicker the slime, the greater the settlement of the pile.