• Journal of the Daesoon Academy of Sciences
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• v.43
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• pp.67-102
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• 2022

The purpose of this study is to analyze the human rights found in the North Korean Constitution and their core problem by focusing on elements of human rights suggested by Daesoon Jinrihoe's doctrine of Haewon-sangsaeng (解冤相生 the Resolution of Grievances for Mutual Beneficence). Haewon-sangsaeng is seemingly the only natural law that could resolve human resentment lingering from the Mutual Contention of the Former World while leading humans work for the betterment of one another. Haewon-sangsaeng, as a natural law, includes the right to life, the right to autonomous decision-making, and duty to act according to human dignity (physical freedom, the freedom of conscience, freedom of religion, freedom of speech, freedom of press, etc.), the right to equal treatment in one's social environment, and the right to ensure the highest level of health through treatment. The North Korean Constitution does not have a character as an institutional device to guarantee natural human rights, the fundamental principle of the Constitution, and stipulates the right of revolutionary warriors to defend dictators and dictatorships. The right to life is specified so that an individual's life belongs to the life of the group according to their socio-political theory of life. Rights to freedom are stipulated to prioritize group interests over individual interests in accordance with the principle of collectivism. The right to equality and the right to health justify discrimination through class discrimination. The right to life provided to North Koreans is not guaranteed due to the death penalty system found within the North Korean Criminal Code and the Criminal Code Supplementary Provisions. The North Korean regime deprives North Koreans of their right to die with dignity through public executions. The North Korean regime places due process under the direction of the Korea Worker's Party, recognizes religion as superstition or opium, and the Korea Worker's Party acknowledge the freedoms of bodily autonomy, religion, media, or press. North Koreans are classified according to their status, and their rights to equality are not guaranteed because they are forced to live a pre-modern lifestyle according to the patriarchal order. In addition, health rights are not guaranteed due biased availability selection and accessibility in the medical field as well as the frequent shortages of free treatments.

• Journal of the Korean Geotechnical Society
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• v.24 no.4
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• pp.101-114
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• 2008

Pressurized grouting is a common technique in geotechnical engineering applications to increase the stiffness and strength of the ground mass and to fill boreholes or void space in a tunnel lining and so on. Recently, the pressurized grouting has been applied to a soil-nailing system which is widely used to improve slope stability. Because interaction between pressurized grouting paste and adjacent ground mass is complicated and difficult to analyze, the soil-nailing design has been empirically performed in most geotechnical applications. The purpose of this study is to analyze the ground behavior induced by pressurized grouting paste with the aid of laboratory model tests. The laboratory tests are carried out for four kinds of granitic residual soils. When injecting pressure is applied to grout, the pressure measured in the adjacent ground initially increases for a while, which behaves in the way of the membrane model. With the lapse of time, the pressure in the adjacent ground decreases down to a value of residual stress because a portion of water in the grouting paste seeps into the adjacent ground. The seepage can be indicated by the fact that the ratio of water/cement in the grouting paste has decreased from a initial value of 50% to around 30% during the test. The reduction of the W/C ratio should cause to harden the grouting paste and increase the stiffness of it, which restricts the rebound of out-moved ground into the original position, and thus increase the in-situ stress by approximately 20% of the injecting pressures. The measured radial deformation of the ground under pressure is in good agreement with the expansion of a cylindrical cavity estimated by the cavity expansion theory. In-situ test revealed that the pullout resistance of a soil nailing with pressurized grouting is about 36% larger than that with regular grouting, caused by grout radius increase, residual stress effect, and/or roughness increase.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.2
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• pp.65-80
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• 2022

Despite the uncertainty and risky factors of startups, the special and critical role of accelerators in carrying out professional nurturing and investment for them is becoming increasingly significant in the startup social-system. However, academic research on investment determinants that have a profound impact on the survival of accelerators is lacking, and there are only a few empirical studies on the classification and importance of factors, and they do not enjoy the benefits of theoretical studies. This study proposes a business model innovation framework based on the business model innovation theory that reflects the nature and properties of startups that are investment targets of accelerators and derives 12 investment decision factors. The framework defines that the target, direction, and performable force of startup innovation are a business model, strategy, and dynamic capability. Besides, the framework analyzes the investment decision factors of the existing accelerators based on the business model innovation framework to verify the suitability and sufficiency of the composition. As a result of the analysis, first, most of the items were faithfully composed from a static point of view of business model innovation, but it was found that the factors related to the core activities to evaluate the activity and customer relationship were insufficient. Second, from the strategic point of view, the necessity of developing factors that can encompass the definition and content of core resources, which are internal strategic factors, was raised. Third, from the dynamic point of view, it was found that many of the investment determinants of accelerators were concentrated on the lower level of dynamic competencies. This can be judged as a result of reflecting the characteristics of a startup that needs to develop a solution with few resources and a small number of team members. In addition, the roles and interrelationships between each factor are not clear, thus it was found as a limiting point for startups to view and evaluate the direction and process in which startups dynamically innovate their business models. This study is considerably differentiated in that it provides a business model innovation framework and offers a theoretical basis for investment determinants by deriving the investment determinants of accelerators based on the framework and design the foundation for subsequent research. The business model innovation framework presented in this study has great implications in that it contributes to the achievement of startups, accelerators, and startup support organizations.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.1
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• pp.63-73
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• 2014

This study was intended to analyze the correlation between the builder's intentions and the colors that are revealed through the analysis of the manifestation of symbolic colors as the signs and symbols that are shown in the traditional space of Soshaewon as one of the representative retreating villa gardens of Chosun Dynasty and the interpretation of the meanings. The research on the traditional colors and the intended background of Soshaewon and so on was conducted by examining the relative literature and the contents as the objects for the empirical analysis were the scenic beauties and spatial elemnts that are shown in the plan of Soshewon and the poems about Soshewon 48 scenes as well as the contents of the poems related to Five Primary Colors that are used based on "the Ideology of Five Elements of the Positive and Negative". Espectially, this study was conducted by dividing the spatial elements shown in Soswaewon broadly into the visual, synesthetic and symbolic & cognitive spaces in order to classify the locations and directions of the spaces and natural objects as the visual space, the seasons, the points of times and the five sensory organs as the synesthetic space and the "Four Moral Begginings" & the "Seven Emotions" of New Confucianism as the symbolic and cognitive space and by analyzing if there are any correlation between the decided intentions and the spatial meanings that are revealed by analyzing the system of five primary colors which are used in each spatial element.7) As a result from the analysis of the colors that are used based on the three spatial components of Soshaewon, it was found that one of Five Primary Colors were used 74 times in total. First, in the visual spatial component, one of the colors was used 18 times in total including 2 times of blue, 1 time of red, 6 times of yellow, 4 times of white and 5 times of black. The fact that yellow symbolizing the source of everything and white symoblizing cleanness and pureness are used relatively more often than blue and red symbolizing nature and life respectively can be interpreted that the builder, Mr. San-bo Yang's intention to build Soshaewon is related to the meaning symbolizing the pure will of the builder who wanted to seclude himself from society rather than to give priority to enjoying nature. Second, in the synesthetic spatial component which are selected from the 48 scenes of Soshaewon, one of Five Primary Colors was used 38 times in total including 11 times of blue, 8 times of red, 4 times of yellow, 5 times of white and 10 times of black. Since blue and red symbolizing nature and life respectively are used more often than yellow and black symbolizing the source of the world and pureness & knowledge respectively, it was interpreted that the builder means to be faithful to the unique basic functions of the retreating villa with which the builder wanted to enjoy his passion for enjoying nature and exploring knowledge even though the builder built the villa garden for the purpose of keeping himself pure while being unstained by the world. Finally, it was analyzed that one of Five Primary Colors was used 18 times in total including 4 times of blue, 5 times of red and 9 times of white in the symbolic and cognitive spatial components of the 48 scenes. Since it was found that white symbolizing the builder's political pureness is used at the same frequency as blue and red symbolizing nature and life respectively are used as a result from the analysis, it was interpreted that the intention of creating Soshaewon was emotionally revealed at the same percentage in the aspects of his political pureness and enjoyment of nature through his poems. Especially, as a result from such 3 kinds of analyses regarding to the frequency of using Five Primary Colors, it was found that the number of times using Five Primary Colors in the synesthetic spatial component was 38 as the highest percentage, around 51% followed by each 18 times as the24.5% respectively in the visual and cognitive & symbolic spatial spaces. Based on such results, it can be interpreted that the builder, Mr. San-bo Yang's intention of creating Soshaewon sympolizes that his intention for enjoying the basic nature and the vitality of nature within the retreating villa garden is hidden at the same proportion as his intention for keeping himself pure from the unrightful world. It was intended to reveal the traditional colors which are hidden in a traditional retreating villa by analyzing the correlation between the symbolic meanings and the spatial components of Soshaewon based on the Five Primary Colors which are originated from the "Ideology of the Five Natural Elements of the Positive and Negative", but it is thought that it is possible to explore whether such a theory can be generally applied to other kinds of retreating villa gardens or not through a study on other retreating villa gardens as other examples in which the builder's apparent pure intentions, such as enjoyment of nature and persuit of study, etc., unlike Soshaewon are hidden.

• Korean Security Journal
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• no.36
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• pp.93-109
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• 2013

This research is mainly based on the experimental result due to seek different outcomes whena certain security motion with a paticular gear is applied in a plausible confrontational situation. For the purpose of this research an Expandable Baton, which is one of the most commonsecurity equipments, was chosen to be applied in a situation of hitting a person's head. Alsothe results will be studied in the view of Kinematic theory. To demonstrate, 10 students who were majeored in Escort Crane studies at 'H' university werechosen as testees. The participants were grouped into two-one is practiced with the 'expanadable baton use program' and the other is pre-practiced. In this report two groups abovewill be reffered as 'group A' and 'group B' for conveniency. There were a number of differences and changes between two groups. Group B took more timethan the other group did. Group A spent about 0.428sec in section 'e2' and 0.230sec in section'e3' while Group B took 0.435sec, 0.232sec in each sections.To add on, more distinctive results were out when it was more focused on physical movements. Two gropus presented considerable changes- in an 'left-right' moving displacement-Group A;$2.16{\pm}0.9cm$ (left side), $3.78{\pm}1.42cm$ (right side), total $5.94{\pm}2.03cm$. Group B; $2.97{\pm}1.01cm$ (left side),$4.56{\pm}1.57cm$ (right side), total $7.53{\pm}2.13cm$.Continuously, different outcomeswere shown between two groups in a 'back and forth' moving displacement-Group A;$32.48{\pm}3.86cm$, $35.21{\pm}4.64cm$, total $69.36{\pm}5.72$. Group B; $34.50{\pm}6.12cm$, $37.04{\pm}3.70cm$, total $71.46{\pm}7.17cm$. Furthermore, changes in an 'up and down' moving displacement were - GroupA; $5.62{\pm}2.41cm$, $4.54{\pm}1.87cm$, total $10.11{\pm}1.57cm$. Group B; $6.33{\pm}1.78cm$, $4.86{\pm}1.85cm$,total $10.68{\pm}1.81cm$. To continue, there were few modifications of degree on participants' joints, espcially on 'Wristjoint', 'Elbow joint' and 'Shoulder joint', depend on different sections -Wrist joint;Group A; e1 $114.62{\pm}7.13$, e2 $68.27{\pm}6.37$, e3 $131.64{\pm}6.27$. Group B; e1 $112.62{\pm}6.13$, e2 $66.28{\pm}7.38$, e3$137.42{\pm}4.28$ and Elbow joint ; Group A e1 $132.31{\pm}6.55$, e2 $117.92{\pm}8.42$, e3 $144.41{\pm}6.32$. Group B; e1 $133.58{\pm}8.56$, e2 $114.45{\pm}8.21$, e3 $139.89{\pm}4.38$. Lastly, degree changes ofshoulder joint were; Group A; e1 $13.55{\pm}3.85$, e2 $131.42{\pm}11.24$, e3 $78.32{\pm}6.28$. Group B; e1$9.45{\pm}1.23$, e2 $136.74{\pm}13.21$, e3 $79.75{\pm}4.24$.

• Journal of Environmental Science International
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• v.4 no.2
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• pp.223-232
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• 1995

New two macrocyclic compounds using as carriers of liquid emulsion menbrame, have been synthesized. These reuslts provide evidance for the usefulness of the theory in designing the systems. The efficiency of selective transport for heavy metal ions have been discussed from the membrane systems that make use of $SCN^-$,<>,$I^-$,CN- and $Cl^-$ ion as co-anions in source phase and make use of $S_2O_3^{2-}$ and $P_2O_7^{4-}$ ion as receiving phase, respectively. The transport rate of M(II) was highest when a maximum amount of the M(II) in the source phase was present as$Cd(SCN)_2$$(P[SCN^-]= 0.40M)$, $Hg(SCN)_2([SCN^-]=0.40M)$ and Pd(CN)$([CN^-]= 0.40M)$. The Cd(II) and Pb(II) over each competitive cations were well transprted with 0.3M-S2032- and 0.3M-P2O74-, respectively in the receiving phase. Results of this study indicate that two criteria must be met in order to have effective macrocycle-mediated transport in these emulsion system. First one must effective extraction of the $M^{n+}$ into the toluene systems. The effectiveness of this extraction is the greatest if locK for $M^{n+}$macrocycle interaction is large and if the macrocycle is very insoluble in the aqueous phase. Second, the ratio of the locK values (or Mn+-receiving phase ($S_2O_3^{2-}$- or $P_2O_7^{4-}$) to $M^{n+}$-macrocycle (($L_1$이나 $L_2$) interaction must be large enough to ensure quantitative stripping of Mn+(($Cd^{2+}$,$Pb^{2+}$)at the toluene receiving Phase interface. $L_1$(3.5-benzo-10,13,18,21-tetraoxa-1,7,diazabicyclo(8,5,5) eicosan) forms a stable ($Cd^{2+}$ and >,$Pb^{2+}$ complexes and $L_1$ is very insoluble in water and its $Cd^{2+}$ and >,$Pb^{2+}$ complex is considerably less stable than $Cd^{2+}$-(S2O3)22- and $Pd^{2+}-P_2O_7^{4-}$ complexes. On the other hand, the stability of the $Hg^{2+}$)+-$L_1$( complex exceed that of the $Hg^{2+}$- (S2O3)22- and Hg2+-P2O74-, and the distribution coefficient of $L_2$(5,8,15,18,23,26-hexaoxa-1,12- diazabicyclo-(10,8,8) octacosane) is much smaller than that of $L_1$. Therefore, the partitioning of Lr is favored by the aqueous receiving Phase, and little heavy metal ions transport is seen despite the large logK for $Hg^{2+}$+-$L_1$ and $Mn^+$($Cd^{2+}$+, $Pb^{2+}$+ and $Hg^{2+}$)-$L_2$ interactions. Key Words : macrocycles, transport, heavy metal, co-anion, source phase, receiveing, complex separation, interaction, destribution coefficient.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.2
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• pp.68-81
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• 2014

This study was conducted to identify the spacialty, to illuminate the existence and values of Myeongwoldae(明月臺) and Forest Myeongwol, and to suggest the sustainable usage, preservation and management plans with the purpose of ecological and cultural landscaping characteristic and value identification. The result of the study is as follows. Castle Myeongwol and Port Myeongwol shows the status of Hallim-eup Myeongwol District which is the administrative center of western Jeju as well as is the fortress. Building Wolgyejeongsa and School Woohakdang, the head temple of education and culture, located in Myeongwol District represents the spaciality of Myeonwol-ri which was the center of education. Stand Myeongwol is one of the most representative Confucian cultural landscapes in Jeju Island and the field of communion with nature where scholars enjoy poetries, nature, changgi(Korean chess), and go in the Joseon Dynasty period. It was found that the current relics of Myeongwoldae was recovered through the maintenance project conducted by Youth Group Myeongwol composed with Hongjong-si(洪鍾時) as the center during the Japanese colonial era in 1931. It seems that the stonework of Myeongwoldae composed of three levels in the order of square, octagon, and circle based on the heaven-man unity theory of Confucianism and the octagon in the middle is the messenger of Cheonwonjibang(天圓地方), in other words, between the square-shaped earth and the circle-shaped sky. It is assumed that both Grand Bridge Myeongwol and Bridge Myeongwol were constructed as arched bridges in early days. Bridge Myeongwol is the only arched bridge remaining in Jeju Island now, which has the modern cultural heritage value. In Forest Myeongwol, 97 taxa of plants were confirmed and in accordance with 'Taxonomic Group and Class Criteria of Floristic Specific Plants', eight taxa were found; Arachniodes aristata of FD IV and Ilex cornuta, Piper kadsura, Litsea japonica, Melia azedarach, Xylosma congestum, Richosanthes kirilowii var. japonica, Dichondra repens, Viburnum odoratissimum var. awabuki of FD III. Otherwise, 14 taxa of naturalized plants including Apium leptophylihum which is imported to Jeju Island only were confirmed. In Forest Myeongwol, 77 trees including 41 Celtis sinensis, 30 Aphananthe aspera, two Wylosma congestum, a Pinus densiflora, a Camellia japonica, a Melia azedarach, and an Ilex cornuta form a colony. Based on the researched data, the preservation and plans of Myeongwoldae and Forest Myeongwol is suggested as follows. Myeongwoldae, Bridge Myeongwol, and Forest Myeongwol should be managed as one integrated division. Bridge Myeongwol, an arched bridge which is hard to be found in Jeju Island is a high-standard stonework requiring long-term preservation plans. Otherwise, Grand Bridge Myeongwol that is exposed to accident risks because of deterioration and needs safety diagnosis requires measures according to the result of precise safety diagnosis. It is desirable to restore it to a two-sluice arched bridge as its initial shape and to preserve and use it as a representative local landmark with Stand Myeongwol. In addition, considering the topophsis based on the analysis result, the current name of Jeju Special Self-Governing Province Monument No. 19 'Myoengwol Hackberry Colony' should change to 'Myeongwol Hackberry-Muku Tree Colony'. In addition, the serial number system which is composed without distinction of hackberry and muku tree should be improved and the regular monitoring of big and old trees, specific plants, and naturalized species is required.

• Journal of Intelligence and Information Systems
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• v.18 no.4
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• pp.59-77
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• 2012

This study focuses on predicting which firms will increase capital by issuing new stocks in the near future. Many stakeholders, including banks, credit rating agencies and investors, performs a variety of analyses for firms' growth, profitability, stability, activity, productivity, etc., and regularly report the firms' financial analysis indices. In the paper, we develop predictive models for rights issues using these financial analysis indices and data mining techniques. This study approaches to building the predictive models from the perspective of two different analyses. The first is the analysis period. We divide the analysis period into before and after the IMF financial crisis, and examine whether there is the difference between the two periods. The second is the prediction time. In order to predict when firms increase capital by issuing new stocks, the prediction time is categorized as one year, two years and three years later. Therefore Total six prediction models are developed and analyzed. In this paper, we employ the decision tree technique to build the prediction models for rights issues. The decision tree is the most widely used prediction method which builds decision trees to label or categorize cases into a set of known classes. In contrast to neural networks, logistic regression and SVM, decision tree techniques are well suited for high-dimensional applications and have strong explanation capabilities. There are well-known decision tree induction algorithms such as CHAID, CART, QUEST, C5.0, etc. Among them, we use C5.0 algorithm which is the most recently developed algorithm and yields performance better than other algorithms. We obtained data for the rights issue and financial analysis from TS2000 of Korea Listed Companies Association. A record of financial analysis data is consisted of 89 variables which include 9 growth indices, 30 profitability indices, 23 stability indices, 6 activity indices and 8 productivity indices. For the model building and test, we used 10,925 financial analysis data of total 658 listed firms. PASW Modeler 13 was used to build C5.0 decision trees for the six prediction models. Total 84 variables among financial analysis data are selected as the input variables of each model, and the rights issue status (issued or not issued) is defined as the output variable. To develop prediction models using C5.0 node (Node Options: Output type = Rule set, Use boosting = false, Cross-validate = false, Mode = Simple, Favor = Generality), we used 60% of data for model building and 40% of data for model test. The results of experimental analysis show that the prediction accuracies of data after the IMF financial crisis (59.04% to 60.43%) are about 10 percent higher than ones before IMF financial crisis (68.78% to 71.41%). These results indicate that since the IMF financial crisis, the reliability of financial analysis indices has increased and the firm intention of rights issue has been more obvious. The experiment results also show that the stability-related indices have a major impact on conducting rights issue in the case of short-term prediction. On the other hand, the long-term prediction of conducting rights issue is affected by financial analysis indices on profitability, stability, activity and productivity. All the prediction models include the industry code as one of significant variables. This means that companies in different types of industries show their different types of patterns for rights issue. We conclude that it is desirable for stakeholders to take into account stability-related indices and more various financial analysis indices for short-term prediction and long-term prediction, respectively. The current study has several limitations. First, we need to compare the differences in accuracy by using different data mining techniques such as neural networks, logistic regression and SVM. Second, we are required to develop and to evaluate new prediction models including variables which research in the theory of capital structure has mentioned about the relevance to rights issue.

• Journal of Intelligence and Information Systems
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• v.26 no.1
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• pp.135-149
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• 2020

Artificial intelligences are changing world. Financial market is also not an exception. Robo-Advisor is actively being developed, making up the weakness of traditional asset allocation methods and replacing the parts that are difficult for the traditional methods. It makes automated investment decisions with artificial intelligence algorithms and is used with various asset allocation models such as mean-variance model, Black-Litterman model and risk parity model. Risk parity model is a typical risk-based asset allocation model which is focused on the volatility of assets. It avoids investment risk structurally. So it has stability in the management of large size fund and it has been widely used in financial field. XGBoost model is a parallel tree-boosting method. It is an optimized gradient boosting model designed to be highly efficient and flexible. It not only makes billions of examples in limited memory environments but is also very fast to learn compared to traditional boosting methods. It is frequently used in various fields of data analysis and has a lot of advantages. So in this study, we propose a new asset allocation model that combines risk parity model and XGBoost machine learning model. This model uses XGBoost to predict the risk of assets and applies the predictive risk to the process of covariance estimation. There are estimated errors between the estimation period and the actual investment period because the optimized asset allocation model estimates the proportion of investments based on historical data. these estimated errors adversely affect the optimized portfolio performance. This study aims to improve the stability and portfolio performance of the model by predicting the volatility of the next investment period and reducing estimated errors of optimized asset allocation model. As a result, it narrows the gap between theory and practice and proposes a more advanced asset allocation model. In this study, we used the Korean stock market price data for a total of 17 years from 2003 to 2019 for the empirical test of the suggested model. The data sets are specifically composed of energy, finance, IT, industrial, material, telecommunication, utility, consumer, health care and staple sectors. We accumulated the value of prediction using moving-window method by 1,000 in-sample and 20 out-of-sample, so we produced a total of 154 rebalancing back-testing results. We analyzed portfolio performance in terms of cumulative rate of return and got a lot of sample data because of long period results. Comparing with traditional risk parity model, this experiment recorded improvements in both cumulative yield and reduction of estimated errors. The total cumulative return is 45.748%, about 5% higher than that of risk parity model and also the estimated errors are reduced in 9 out of 10 industry sectors. The reduction of estimated errors increases stability of the model and makes it easy to apply in practical investment. The results of the experiment showed improvement of portfolio performance by reducing the estimated errors of the optimized asset allocation model. Many financial models and asset allocation models are limited in practical investment because of the most fundamental question of whether the past characteristics of assets will continue into the future in the changing financial market. However, this study not only takes advantage of traditional asset allocation models, but also supplements the limitations of traditional methods and increases stability by predicting the risks of assets with the latest algorithm. There are various studies on parametric estimation methods to reduce the estimated errors in the portfolio optimization. We also suggested a new method to reduce estimated errors in optimized asset allocation model using machine learning. So this study is meaningful in that it proposes an advanced artificial intelligence asset allocation model for the fast-developing financial markets.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.1
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• pp.63-101
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• 2020

'Flight safety zone' means a zone that the Minister of National Defense designates under Articles 4 and 6 of the Protection of Military Bases and Installations Act (hereinafter 'PMBIA') for the safety of flight during takeoff and landing of military aircrafts. The purpose of flight safety zone is to contribute to the national security by providing necessary measures for the protection of military bases and installations and smooth conduct of military operations. In this case, when the state set and used the flight safety zone, the landowner claimed restitution of unjust enrichment against the country. This article is an analysis based on the existing legal theory regarding the legitimacy of plaintiff's claim, and the summary of the discussion is as follows. A person who without any legal ground derives a benefit from the property or services of another and thereby causes loss to the latter shall be bound to return such benefit (Article 741 of the Civil Act). Since the subject matter is an infringing profit, the defendant must prove that he has a legitimate right to retain the profit. The State reserves the right to use over the land designated as a flight safety zone in accordance with legitimate procedures established by the PMBIA for the safe takeoff and landing of military aircrafts. Therefore, it cannot be said that the State gained an unjust enrichment equivalent to the rent over the land without legal cause. Expropriation, use or restriction of private property from public necessity and compensation therefor shall be governed by Act: provided, that in such a case, just compensation shall be paid (Article 23 (1) of the Constitution of The Republic of KOREA). Since there is not any provision in the PMBIA for loss compensation for the case where a flight safety zone is set over land as in this case, next question would be whether or not it is unconstitutional. Even if it is designated as a flight safety zone and the use and profits of the land are limited, the justification of the purpose of the flight safety zone system, the appropriateness of the means, the minimization of infringement, and the balance of legal interests are still recognized; thus just not having any loss compensation clause does not make the act unconstitutional. In conclusion, plaintiff's claim for loss compensation based on the 'Act on Acquisition of and Compensation for land, etc. for Public Works Projects', which has no provision for loss compensation due to public limits, is unjust.