• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.279-290
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• 2021

This study evaluated the economic feasibility of facility farms according to the introduction of the ultra-high density pot cultivation (UHDPC) for mango. The basic model was selected as a representative farmhouse case in the Jeonnam region, and seven scenarios for conventional crops were tested. The economic feasibility of crop switching was analyzed through partial budget analysis (PBA). The PBA analysis results were supplemented by adding a sensitivity analysis and a break-even point (BEP) analysis. As a result of the analyses, it was found that crop conversion was economical because the increase in the profit coefficient was greater than the increase in the loss coefficient due to the introduction of mango for all conventional crops. The economics of introducing mango was more sensitive to changes in gross income than to changes in cost items. The results show the detailed conditions of crop selection according to the conditions and preferences of individual farms by presenting the direction of increase and decrease by budget item and information on the amount of increase or decrease. In particular, the BEP analysis result, which is about half of the farms case, is significant in that it presents the minimum target value according to production and market risks.

• 한국노년학
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• v.37 no.4
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• pp.835-852
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• 2017

The purpose of this study was to examine the moderating effects of social support on material hardship of low-income elderly people that have been excluded from the National Basic Livelihood Security System. For this research, data of 255 persons aged 65 and over were collected using a survey conducted in 2014 by the National Human Rights Commission of Korea on the minimum living cost of low-income household. Data analysis was performed through descriptive analysis, correlation analysis, and multiple regression analysis with STATA13. According to the results, the average level of material hardship in low-income elderly people was 1.45 out of 6, with the most hardship shown in heating and health care. The results of multiple regression analysis showed that when low-income elderly people became excluded from the system, they suffered more than the recipients. They also showed that the social support system of low-income elderly people brought a negative impact on their material hardship when they were connected by the strong social support system. In other words, social support system reduced their material hardship caused by exclusion. Based on the results, this study suggests some practical and political means to reduce material hardship of low-income elderly people.

• Journal of Korea Water Resources Association
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• v.54 no.7
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• pp.475-484
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• 2021

The optimal design for water distribution system (WDS) is not only satisfying the minimum required water pressure of the nodes, but also minimizing pipe cost, etc. The number of designs of WDS increases exponentially due to the arrangement of various pipes. Various optimization algorithms were applied to propose an optimized design of WDS. In this study, Modified Hybrid Vision Correction Algorithm (MHVCA) with improved self-adapting parameter was applied to optimal design of WDS. The performance was improved by changing the Hybrid Rate (HR) of the existing Hybrid Vision Correction Algorithm (HVCA) to nonlinear HR. To verify the performance of the proposed MHVCA, it applied to mathematical problems consisting of 2 and 30 decision variables and constrained mathematical problems. In order to review the application results of MHVCA, it was compared with Harmony Search (HS), Improved Harmony Search (IHS), Vision Correction Algorithm (VCA) and HVCA. Finally, MHVCA was applied to the optimal design problem of WDS and the results were compared with other algorithms. MHVCA showed better results than other algorithms in mathematical problems and WDS problem. MHVCA will be able to show good results by applying to various water resource engineering problems as well as problems applied in this study.

• Journal of the Korean Geotechnical Society
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• v.38 no.11
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• pp.43-54
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• 2022

The settlement at the railroad foundation is often the leading cause of track irregularity and potential derailment. The control of such deformation is considered necessary in track maintenance practice. Nevertheless, the monitoring process performed by in situ surveying requires an excessive amount of manpower and cost. The InSAR, a remote sensing technique by RADAR satellite, is used to overcome such a burden. The PS-InSAR technique is preferred for a long-term precise monitoring method. However, this study aims to obtain relatively brief analysis results from only two satellite images using the D-InSAR technique, while a minimum of 25 images are required for PS-InSAR. This study verifies the precision of D-InSAR within a few millimeters by inspecting railroad facilities and land settlements in Korea Railroad Research Institute's test track with images from TerraSAR-X Satellite. Multiple corner reflectors were adopted and installed on an embankment and the building roof to raise the surface reflectivity. Those reflectors were slightly adjusted periodically to verify the detecting performance. The results revealed the optimum distance between corner reflectors. Further, the deformation of railway tracks, slopes, and concrete structures was analyzed successively. In conclusion, this study indicates that the D-InSAR technique effectively monitors the short-term deformation of a broad area such as railway structures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.706-711
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• 1997

Low supply of water is generally the most serious factor limiting rice production. The experiment was conducted to identify the reasonable method for minimum irrigation under ridge direct seeding on dry paddy, at National Honam Agricultural Experiment Station, RDA in 1996. The results showed that the reduction ratio of irrigation water was high in order of furrow irrigation at 15-day>furrow irrigation at 10-day>flooding irrigation at 10-day>, and furrow irrigation at 5-day intervals. However, milled rice yield was high in the furrow irrigation at 5-day intervals and in flooding irrigation at 10-day intervals due to high ripened grain as compared with other treatments indicating two treatments were the most reasonable irrigation methods in terms of saving the labor cost and water supply as well as the admittable yield performance.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6C
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• pp.251-258
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• 2009

In this study, the optimum design conditions for embankment construction on soft clay layer improved by soil compaction pile (SCP) are discussed by comparing the practical design method to the reliability design which is based on the loss function and advanced first order second moment (AFOSM) method. The results are summarized as follows; 1) the relationship between safety factor and failure probability becomes heavy exponentially, failure probability decreases rapidly till 1% approximately until safety factor is smaller than 1.2 and after then, failure probability decrease gradually along the increase of the safety factor. The design safety factor of 1.2 may be the critical value that has been established on considering both relationships appropriately, 2) the safety factor of 1.15 at the minimum expected total cost is a little smaller than the design safety factor of 1.2 and the failure probability is about 1%, 3) the sensitivities of the ratio of stress share and the internal friction angle of sand is larger than the variables related the undrained shear strength of soft layer. This result means that the distribution characteristic of n and ${\phi}$ influences on the stability analysis considerably and they should be considered necessarily on stability analysis of embankment on soft layer improved by SCP, 4) new failure points of the input variables at the design safety factor of 1.2(below failure probability of 0.1~0.3%) is far 1~2 times of standard deviation from the initial design values of themselves.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.34 no.3
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• pp.393-401
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• 2024

Recently, the Internet of Things (IoT) has been widely used in industries and daily life that directly affect human safety, life, and assets. However, IoT devices, which need to meet low-cost, lightweight, and low-power requirements, face a significant problem of shortened battery lifetime due to battery draining attacks and interference. To solve this problem, the 802.11ba standard for the Wake-up Receiver (WuR) has emerged, this feature is playing a crucial role in minimizing energy consumption. However, the WuR protocol did not consider security mechanisms in order to reduce latency and overhead. Therefore, in this study, anAdaptive Power Saving Mechanism (APSM) is proposed for low-power WuR to counter battery draining attacks. APSM can minimize abnormally occurring power consumption by exponentially increasing power-saving time in environments prone to attacks. According to experimental results, the proposed APSM improved energy consumption efficiency by a minimum of 13.77% compared to the traditional Legacy Power Saving Mechanism (LPSM) when attack traffic ratio is 10% or more of the total traffic.

• Steel and Composite Structures
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• v.50 no.5
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• pp.595-608
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• 2024

In this study, aluminum lathe waste was used by replacing aggregates in certain proportions in order to obtain expansive concrete using recycled materials. For this reason, five different aluminum wastes of 1%, 2%, 3%, 4% and 5% were selected and also reference without aluminum waste was produced. Based on the mechanical tests conducted, which included slump, compression, splitting tensile, and flexural tests, it was evident that the workability of the material declined dramatically once the volume ratio of aluminum exceeded 2%. As determined by the compressive strength test (CST), the CS of concrete (1% aluminum lathe wastes replaced with aggregate) was 11% reducer than that of reference concrete. It was noted that the reference concrete's CS values, which did not include aluminum waste, were greater than those of the concrete that contained 5% aluminum. When comparing for splitting tensile strength (STS), it was observed that the results of STS generally follow the parallel inclination as the CS. The reduction in these strengths when 1% aluminum is utilized is less than 10%. These ratios modified 18% when flexural strength (FS) is considered. Therefore, 1% of aluminum waste is recommended to obtain expansive concrete with recycled materials considering minimum loss of strength. Moreover, Scanning Electron Microscope (SEM) analysis was performed and the results also confirm that there was expansion in the aluminum added concrete. The presence of pores throughout the concrete leads to the formation of gaps, resulting in its expansion. Additionally, for practical applications, basic equations were developed to forecast the CS, STS, and FS of the concrete with aluminum lathe waste using the data already available in the literature and the findings of the current study. In conclusion, this study establishes that aluminum lathe wastes are suitable, readily available in significant quantities, locally sourced eco-materials, cost-effective, and might be selected for construction using concrete, striking a balance among financially and ecological considerations.

• The Korean Society of Law and Medicine
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• v.21 no.1
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• pp.153-185
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• 2020

In principle, even if serious consequences such as death or serious injury of a patient occur as a result of a medical accident, if the medical malpractice of a health care worker is not recognized, the health care worker is not held liable for said consequences. However, with the opening of the Korea Medical Dispute Mediation and Arbitration Agency on April 7, 2012, a system was established to compensate health care personnel for their medical malpractices only in the case of "injuries caused by medical accidents in the course of childbirth" (hereinafter referred to as "program for compensation of medical accidents"). Article 46 paragraph 1 of the current Medical Dispute Mediation Act, which is the basis of the Force Majeure Medical Accident Compensation System, stipulates that "medical accidents under delivery" claims are to be determined by the Medical Accident Compensation Review Committee are subject to the compensation project. And the details of the compensation, ratio of sharing financial resources for compensation, scope of compensation, and the guidelines and procedure for the payment of compensations are prescribed by Presidential Decree. In other words, the Presidential Decree requires the state to pay 70 percent of the compensation funds, and 30 percent of the above funds among health care providers. The Constitutional Court has decided on the 2015Hun-Ga13 that the scope of the health care institution's founders and the share of the compensation funds cannot be directly determined by the law, and that the portion delegated by the Presidential decree does not violate the Principle of Legal Protection nor Comprehensive Nondelegation Doctrine. However, this can be seen as an exclusion of accountability for force-induced delivery accidents even if there is no negligence of the medical staff. If the nature of the system is a type of social security system with a social compensatory nature, it could consider eliminating the health care innovator's cost-sharing provisions, leaving the full cost to the state. However, it is also necessary to review institutional protocols that strengthen the efforts of medical institutions in areas such as analysis of the causes of medical accidents and measures to prevent their recurrence. In addition, I think that the conclusion of the Act is in line with the purpose of the Comprehensive Wage Support Regulations that at minimum the law sets an upper limit of the compensation funds that are to be paid by health and medical institutions. Moreover, it is reasonable for the Medical Accident Compensation Review Committee to specify gestational age and weight of births, which are the criteria for compensation, under the Enforcement Decree of the Medical Dispute Mediation Act, in relation to the criteria for payment of contributions by the Medical Accident Compensation Review Committee, and to set the detailed criteria.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.975-976
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• 1993

This talk presents the overview of the author's research and development activities on fuzzy inference hardware. We involved it with two distinct approaches. The first approach is to use application specific integrated circuits (ASIC) technology. The fuzzy inference method is directly implemented in silicon. The second approach, which is in its preliminary stage, is to use more conventional microprocessor architecture. Here, we use a quantitative technique used by designer of reduced instruction set computer (RISC) to modify an architecture of a microprocessor. In the ASIC approach, we implemented the most widely used fuzzy inference mechanism directly on silicon. The mechanism is beaded on a max-min compositional rule of inference, and Mandami's method of fuzzy implication. The two VLSI fuzzy inference chips are designed, fabricated, and fully tested. Both used a full-custom CMOS technology. The second and more claborate chip was designed at the University of North Carolina(U C) in cooperation with MCNC. Both VLSI chips had muliple datapaths for rule digital fuzzy inference chips had multiple datapaths for rule evaluation, and they executed multiple fuzzy if-then rules in parallel. The AT & T chip is the first digital fuzzy inference chip in the world. It ran with a 20 MHz clock cycle and achieved an approximately 80.000 Fuzzy Logical inferences Per Second (FLIPS). It stored and executed 16 fuzzy if-then rules. Since it was designed as a proof of concept prototype chip, it had minimal amount of peripheral logic for system integration. UNC/MCNC chip consists of 688,131 transistors of which 476,160 are used for RAM memory. It ran with a 10 MHz clock cycle. The chip has a 3-staged pipeline and initiates a computation of new inference every 64 cycle. This chip achieved an approximately 160,000 FLIPS. The new architecture have the following important improvements from the AT & T chip: Programmable rule set memory (RAM). On-chip fuzzification operation by a table lookup method. On-chip defuzzification operation by a centroid method. Reconfigurable architecture for processing two rule formats. RAM/datapath redundancy for higher yield It can store and execute 51 if-then rule of the following format: IF A and B and C and D Then Do E, and Then Do F. With this format, the chip takes four inputs and produces two outputs. By software reconfiguration, it can store and execute 102 if-then rules of the following simpler format using the same datapath: IF A and B Then Do E. With this format the chip takes two inputs and produces one outputs. We have built two VME-bus board systems based on this chip for Oak Ridge National Laboratory (ORNL). The board is now installed in a robot at ORNL. Researchers uses this board for experiment in autonomous robot navigation. The Fuzzy Logic system board places the Fuzzy chip into a VMEbus environment. High level C language functions hide the operational details of the board from the applications programme . The programmer treats rule memories and fuzzification function memories as local structures passed as parameters to the C functions. ASIC fuzzy inference hardware is extremely fast, but they are limited in generality. Many aspects of the design are limited or fixed. We have proposed to designing a are limited or fixed. We have proposed to designing a fuzzy information processor as an application specific processor using a quantitative approach. The quantitative approach was developed by RISC designers. In effect, we are interested in evaluating the effectiveness of a specialized RISC processor for fuzzy information processing. As the first step, we measured the possible speed-up of a fuzzy inference program based on if-then rules by an introduction of specialized instructions, i.e., min and max instructions. The minimum and maximum operations are heavily used in fuzzy logic applications as fuzzy intersection and union. We performed measurements using a MIPS R3000 as a base micropro essor. The initial result is encouraging. We can achieve as high as a 2.5 increase in inference speed if the R3000 had min and max instructions. Also, they are useful for speeding up other fuzzy operations such as bounded product and bounded sum. The embedded processor's main task is to control some device or process. It usually runs a single or a embedded processer to create an embedded processor for fuzzy control is very effective. Table I shows the measured speed of the inference by a MIPS R3000 microprocessor, a fictitious MIPS R3000 microprocessor with min and max instructions, and a UNC/MCNC ASIC fuzzy inference chip. The software that used on microprocessors is a simulator of the ASIC chip. The first row is the computation time in seconds of 6000 inferences using 51 rules where each fuzzy set is represented by an array of 64 elements. The second row is the time required to perform a single inference. The last row is the fuzzy logical inferences per second (FLIPS) measured for ach device. There is a large gap in run time between the ASIC and software approaches even if we resort to a specialized fuzzy microprocessor. As for design time and cost, these two approaches represent two extremes. An ASIC approach is extremely expensive. It is, therefore, an important research topic to design a specialized computing architecture for fuzzy applications that falls between these two extremes both in run time and design time/cost. TABLEI INFERENCE TIME BY 51 RULES {{{{Time }}{{MIPS R3000 }}{{ASIC }}{{Regular }}{{With min/mix }}{{6000 inference 1 inference FLIPS }}{{125s 20.8ms 48 }}{{49s 8.2ms 122 }}{{0.0038s 6.4㎲ 156,250 }} }}