• Journal of the Korean Magnetics Society
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• v.10 no.3
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• pp.123-132
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• 2000

Cerium substituted YIG thin films were grown by rf magnetron sputter techniques. We investigated the effects of post-deposition heat-treatment as well as various deposition parameters such as substrate materials, substrate temperature. sputter power, and sputter gas types on the crystallinity, chemical composition, microstructure and magnetic characteristics of the films. Post-deposition heat treatment over 750 $\^{C}$ was applied to crystallize as-prepared amorphous films, and a strong tendency of particular crystallographic planes tying parallel to substrate surface was observed for the post-deposition heat-treated films on GGG substrate. The chemical composition of the films exhibited a wide range of chemical stoichiometry depending on the oxygen fraction of sputter gas, and in particular the composition of the film deposited in sputter gas with an oxygen fraction of R = 10% was Ce$\_$0.23/Y$\_$1.30/Fe$\_$3.50/O$\_$12/. With raising the temperature of post-deposition heat-treatment from 900 $\^{C}$ to 1100 $\^{C}$, the surface roughness of the film on GGG substrates increased from about 3 nm to 40 nm, but their coercive force and ferromagnetic resonance line width decreased from 0.477 kA/m to 0.369 kA/m and from 12.5 kA/m to 8.36 kA/m, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.363-363
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• 2008

The development of dry etching process for sapphire wafer with plasma has been key issues for the opto-electric devices. The challenges are increasing control and obtaining low plasma induced-damage because an unwanted scattering of radiation is caused by the spatial disorder of pattern and variation of surface roughness. The plasma-induced damages during plasma etching process can be classified as impurity contamination of residual etch products or bonding disruption in lattice due to charged particle bombardment. Therefor, fine pattern technology with low damaged etching process and high etch rate are urgently needed. Until now, there are a lot of reports on the etching of sapphire wafer with using $Cl_2$/Ar, $BCl_3$/Ar, HBr/Ar and so on [1]. However, the etch behavior of sapphire wafer have investigated with variation of only one parameter while other parameters are fixed. In this study, we investigated the effect of pressure and other parameters on the etch rate and the selectivity. We selected $BCl_3$ as an etch ant because $BCl_3$ plasmas are widely used in etching process of oxide materials. In plasma, the $BCl_3$ molecule can be dissociated into B radical, $B^+$ ion, Cl radical and $Cl^+$ ion. However, the $BCl_3$ molecule can be dissociated into B radical or $B^+$ ion easier than Cl radical or $Cl^+$ ion. First, we evaluated the etch behaviors of sapphire wafer in $BCl_3$/additive gases (Ar, $N_2,Cl_2$) gases. The behavior of etch rate of sapphire substrate was monitored as a function of additive gas ratio to $BCl_3$ based plasma, total flow rate, r.f. power, d.c. bias under different pressures of 5 mTorr, 10 mTorr, 20 mTorr and 30 mTorr. The etch rates of sapphire wafer, $SiO_2$ and PR were measured with using alpha step surface profiler. In order to understand the changes of radicals, volume density of Cl, B radical and BCl molecule were investigated with optical emission spectroscopy (OES). The chemical states of $Al_2O_3$ thin films were studied with energy dispersive X-ray (EDX) and depth profile anlysis of auger electron spectroscopy (AES). The enhancement of sapphire substrate can be explained by the reactive ion etching mechanism with the competition of the formation of volatile $AlCl_3$, $Al_2Cl_6$ or $BOCl_3$ and the sputter effect by energetic ions.

• Journal of Technologic Dentistry
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• v.25 no.1
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• pp.173-185
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• 2003

This study mainly intends to determine the factors for which dental technicians are satisfied with their jobs and how much the resulting job transfer rate is and thus to identify the correlation between them. For these purpose, 200 subjects were sampled out of dental technicians in Seoul and Incheon, and the survey was performed from July 19, 2002 to August 15 (for 25 days) with self-administered questionnaire. Out of all collected questionnaires, 131 pieces(65.5%) were addressed for this study. As for the tools for this study, the structured questionnaire was used with its proven reliability and feasibility, and the contents of questionnaire consisted of 32 questions on the basis of related references. The contents of questionnaire were categorized into 3 sections: General attribute of subjects; Factors for which dental technicians are satisfied with their jobs; and their intention of job transfer. The questionnaire consisted of total 32 questions which included general attribute of subjects(10 questions), factors of their satisfaction with jobs(17 questions) and intention of job transfer(5 questions). The data analysis was processed by computerized system with SPSS(Statistical Package for Social Sciences). Statistical analysis techniques included frequency, percentage, T-test, F-test analysis and regression analysis. As a result of those analyses, the conclusion can be summarized as follows: 1. As a result of analyzing the factors for which the subjects were satisfied with their jobs, it was found that there were significant differences in career and job title out of question items(P<0.001). It was also shown that the factors of subjects' satisfaction averaged 3.43, which was considerably higher value than I expected. It was found that job and management factors were major job satisfaction factors. 2. As a result of analyzing the intention of subjects to decide their job transfer, it was found that there were significant differences in job title and marital status out of question items(P<0.001). It was shown that the total average of the intention of their job transfer amounted to 3.06. It was shown that dental technicians have relatively higher intention of job transfer from their current work place. 3. It was found that there was inverse correlation between the factors of subjects' satisfaction with their jobs and their intention of job transfer(r=-0.490, P<0.05). Likewise, it was also found that there was inverse correlation mostly between the evaluation value for each independent variable region in term of each factor of job satisfaction and the value for the intention of job transfer. In view of these correlations, it was concluded that higher job satisfaction likely led to lower job transfer. 4. As a result of regression analysis so as to determine the influences of job satisfaction factors on the intention of job transfer, it was found that the highest influential factor was management factor. And it was shown that the test values of model were statistically significant and its explanatory power amounted to 54.6%.

• Journal of Digital Convergence
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• v.16 no.1
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• pp.409-420
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• 2018

This is a convergence study to investigate the factors affecting the psychological happiness of leisure sports participants(social baseball club) and to present a strategy for effective program development. The subjects of this study were 151 participants of social baseball clubs in J-do area and collected data by self-reported questionnaire. Data were analyzed by descriptive statistics, t-test, ANOVA, correlation analysis and stepwise multiple regression analysis. The results of this study were the explanatory power was 54.1% with psychological happiness, quality of life, self-efficacy. As a result, it was confirmed that strengthening interpersonal relationship ability, positive reinforcement of self-efficacy, and quality of life were important for improvement of psychological happiness. and in the future, it is necessary to study repeatedly to confirm the influence of psychological through objective measurement.

• Journal of agricultural medicine and community health
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• v.41 no.3
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• pp.129-139
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• 2016

Objective: The purpose of this study was to identify the predictors and frailty level in the frail elderly receiving home visiting health care services. Methods: The subjects were 177 frail elders aged over 65 registered in the home visiting health care services of three public health centers in Daegu. The data collection was performed from June 9 to June 24, 2015. This study used descriptive statistics, t-test, ANOVA, scheffe test and stepwise multiple regression by SPSS Win 18.0 program. Results: The mean of the frailty score was 10.05 (${\pm}4.52$). Age and life satisfaction were the significant factors related to the frailty score in frail elderly. Health promotion behavior, empowerment, social participation and perceived health status had a negative correlation with the frailty score. Thirty seven point four percent of the variance in the frailty score can be explained by perceived health status (${\beta}=-0.398$, p<0.001), health promotion behavior (${\beta}=-0.251$, p<0.001) and age (${\beta}=0.232$, p<0.001)(Cum $R^2=0.374$, F=25.744, p<0.001). Perceived health status was the most important factor related to the frailty score in our study. Conclusions: An integrative care program which includes these significant variables of subjects is essential to prevent the deterioration of frailty in frail elderly.

• Journal of Animal Science and Technology
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• v.51 no.3
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• pp.201-206
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• 2009

Seventeen porcine microsatellite (MS) markers recommended by the EID+DNA Tracing EU project, ISAG and Roslin institute were selected for the use in porcine individual and brand identification. The MSA, CERVUS, FSTAT, GENEPOP and API-CALC programs were applied for calculating heterozygosity indices. By considering the hetreozygosity value and PCR product size of each marker, we established a MS marker set composed of 13 MS markers (SW936, SW951, SW787, S00090, S0026, SW122, SW857, S0005, SW72, S0155, S0225, SW24 and SW632) and two sexing markers. The expected probability of identity among genotypes of random individuals (PI), probability of identity among genotypes from random half sibs ($PI_{half-sibs}$) and among genotypes of random individuals, probability of identity among genotypes from random sibs($PI_{sibs}$) were estimated as $2.47\times10^{-18}$, $6.39\times10^{-13}$ and $1.08\times10^{-8}$, respectively. The results indicate that the established marker set can provide a sufficient discriminating power in both individual and parentage identification for the commercial pigs produced in Korea.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.625-628
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• 2015

POLARBEAR is a ground-based experiment located in the Atacama desert of northern Chile. The experiment is designed to measure the Cosmic Microwave Background B-mode polarization at several arcminute resolution. The CMB B-mode polarization on degree angular scales is a unique signature of primordial gravitational waves from cosmic inflation and B-mode signal on sub-degree scales is induced by the gravitational lensing from large-scale structure. Science observations began in early 2012 with an array of 1.274 polarization sensitive antenna-couple Transition Edge Sensor (TES) bolometers at 150 GHz. We published the first CMB-only measurement of the B-mode polarization on sub-degree scales induced by gravitational lensing in December 2013 followed by the first measurement of the B-mode power spectrum on those scales in March 2014. In this proceedings, we review the physics of CMB B-modes and then describe the Polarbear experiment, observations, and recent results.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.427-435
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• 2023

Changes in flowering time due to weather fluctuations impact plant growth and ecosystem dynamics. Accurate prediction of flowering timing is crucial for effective forest ecosystem management. This study uses a process-based model to predict flowering timing in 2023 for five major tree species in Korean forests. Models are developed based on nine years (2009-2017) of flowering data for Abeliophyllum distichum, Robinia pseudoacacia, Rhododendron schlippenbachii, Rhododendron yedoense f. poukhanense, and Sorbus commixta, distributed across 28 regions in the country, including mountains. Weather data from the Automatic Mountain Meteorology Observation System (AMOS) and the Korea Meteorological Administration (KMA) are utilized as inputs for the models. The Single Triangle Degree Days (STDD) and Growing Degree Days (GDD) models, known for their superior performance, are employed to predict flowering dates. Daily temperature readings at a 1 km spatial resolution are obtained by merging AMOS and KMA data. To improve prediction accuracy nationwide, random forest machine learning is used to generate region-specific correction coefficients. Applying these coefficients results in minimal prediction errors, particularly for Abeliophyllum distichum, Robinia pseudoacacia, and Rhododendron schlippenbachii, with root mean square errors (RMSEs) of 1.2, 0.6, and 1.2 days, respectively. Model performance is evaluated using ten random sampling tests per species, selecting the model with the highest R². The models with applied correction coefficients achieve R² values ranging from 0.07 to 0.7, except for Sorbus commixta, and exhibit a final explanatory power of 0.75-0.9. This study provides valuable insights into seasonal changes in plant phenology, aiding in identifying honey harvesting seasons affected by abnormal weather conditions, such as those of Robinia pseudoacacia. Detailed information on flowering timing for various plant species and regions enhances understanding of the climate-plant phenology relationship.

• Asia Marketing Journal
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• v.14 no.1
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• pp.1-24
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• 2012

Nowadays, customer satisfaction has been one of company's major objectives, and the index to measure and communicate customer satisfaction has been generally accepted among business practices. The major issues of CSI(customer satisfaction index) are three questions, as follows: (a)what level of customer satisfaction is tolerable, (b)whether customer satisfaction and company performance has positive causality, and (c)what to do to improve customer satisfaction. Among these, the second issue is recently attracting academic research in several perspectives. On this study, the second issue will be addressed. Many researchers including Anderson have regarded customer satisfaction as core competencies, such as brand equity, customer equity. They want to verify following causality "customer satisfaction → market performance(market share, sales growth rate) → financial performance(operating margin, profitability) → corporate value performance(stock price, credit ratings)" based on the process model of marketing performance. On the other hand, Insoo Jeon and Aeju Jeong(2009) verified sequential causality based on the process model by the domestic data. According to the rejection of several hypotheses, they suggested the balance model of marketing performance as an alternative. The objective of this study, based on the existing process model, is to examine the causal relationship between customer satisfaction and corporate value performance. Anderson and Mansi(2009) proved the relationship between ACSI(American Customer Satisfaction Index) and credit ratings using 2,574 samples from 1994 to 2004 on the assumption that credit rating could be an indicator of a corporate value performance. The similar study(Sangwoon Yoon, 2010) was processed in Korean data, but it didn't confirm the relationship between KCSI(Korean CSI) and credit ratings, unlike the results of Anderson and Mansi(2009). The summary of these studies is in the Table 1. Two studies analyzing the relationship between customer satisfaction and credit ratings weren't consistent results. So, in this study we are to test the conflicting results of the relationship between customer satisfaction and credit ratings based on the research model considering Korean credit ratings. To prove the hypothesis, we suggest the research model as follows. Two important features of this model are the inclusion of important variables in the existing Korean credit rating system and government support. To control their influences on credit ratings, we included three important variables of Korean credit rating system and government support, in case of financial institutions including banks. ROA, ER, TA, these three variables are chosen among various kinds of financial indicators since they are the most frequent variables in many previous studies. The results of the research model are relatively favorable : R², F-value and p-value is .631, 233.15 and .000 respectively. Thus, the explanatory power of the research model as a whole is good and the model is statistically significant. The research model has good explanatory power, the regression coefficients of the KCSI is .096 as positive(+) and t-value and p-value is 2.220 and .0135 respectively. As a results, we can say the hypothesis is supported. Meanwhile, all other explanatory variables including ROA, ER, log(TA), GS_DV are identified as significant and each variables has a positive(+) relationship with CRS. In particular, the t-value of log(TA) is 23.557 and log(TA) as an explanatory variables of the corporate credit ratings shows very high level of statistical significance. Considering interrelationship between financial indicators such as ROA, ER which include total asset in their formula, we can expect multicollinearity problem. But indicators like VIF and tolerance limits that shows whether multicollinearity exists or not, say that there is no statistically significant multicollinearity in all the explanatory variables. KCSI, the main subject of this study, is a statistically significant level even though the standardized regression coefficients and t-value of KCSI is .055 and 2.220 respectively and a relatively low level among explanatory variables. Considering that we chose other explanatory variables based on the level of explanatory power out of many indicators in the previous studies, KCSI is validated as one of the most significant explanatory variables for credit rating score. And this result can provide new insights on the determinants of credit ratings. However, KCSI has relatively lower impact than main financial indicators like log(TA), ER. Therefore, KCSI is one of the determinants of credit ratings, but don't have an exceedingly significant influence. In addition, this study found that customer satisfaction had more meaningful impact on corporations of small asset size than those of big asset size, and on service companies than manufacturers. The findings of this study is consistent with Anderson and Mansi(2009), but different from Sangwoon Yoon(2010). Although research model of this study is a bit different from Anderson and Mansi(2009), we can conclude that customer satisfaction has a significant influence on company's credit ratings either Korea or the United State. In addition, this paper found that customer satisfaction had more meaningful impact on corporations of small asset size than those of big asset size and on service companies than manufacturers. Until now there are a few of researches about the relationship between customer satisfaction and various business performance, some of which were supported, some weren't. The contribution of this study is that credit rating is applied as a corporate value performance in addition to stock price. It is somewhat important, because credit ratings determine the cost of debt. But so far it doesn't get attention of marketing researches. Based on this study, we can say that customer satisfaction is partially related to all indicators of corporate business performances. Practical meanings for customer satisfaction department are that it needs to actively invest in the customer satisfaction, because active investment also contributes to higher credit ratings and other business performances. A suggestion for credit evaluators is that they need to design new credit rating model which reflect qualitative customer satisfaction as well as existing variables like ROA, ER, TA.

• Strategy21
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• s.32
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• pp.222-270
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• 2013

서구 근대 국제관계학의 태동은 "전쟁의 원인"을 밝혀내려고 했던 유럽 지식인들의 학문적 도전에서부터 비롯되었다고 할 수 있다. 1, 2차 세계대전의 잔혹함을 겪으면서 이들은 전쟁(특히 전쟁의 원인)에 대한 좀 더 과학적인 연구를 통해 어떻게 하면 국가들 간의 전쟁을 예방할 수 있을까에 집중해 왔다. 이러한 학문적 경향을 반영한 것이 잘 알려진 미국 미시간 대학의 "전쟁 상관성 연구 프로젝트(Correlates of War Project)"이다. 이는 나폴레옹 전쟁이 끝나고 비엔나체제가 시작된 1815년 이후 국가들 간 발생한 모든 전쟁 관련 자료를 데이터베이스화하여,국제관계학자들이 전쟁(Interstate War)이나 군사분쟁(Militarized Interstate Disputes)을 정량 또는 정성적으로 연구할 수 있도록 다양한 정보들을 제공하고 있다. 최근 Paul F. Diehl, William R. Thompson과 같은 학자들은 전쟁을 분석단위로 하는 전쟁의 원인(Causes of War)을 연구하는 학풍에서 벗어나, 국가들 간의 분쟁과 전쟁을 연구하기 위해 숙적관계(Rivalry)라는 새로운 분석의 단위를 제시하였다. 숙적관계는 국제관계에 있어서 지속적으로 분쟁 또는 전쟁을 일으키는, 즉 무력분쟁의 긴 역사를 가지고 있는, 두 국가를 일컫는다. 국가들 간의 숙적관계는 학자들에 따라 Interstate Rivalry, Enduring Rivalry, Strategic Rivalry 등 다양한 정의와 성격을 갖고 있다. 이러한 국가들의 사례로는 2차대전 이전까지 프랑스-독일 관계, 2차대전 이후 중동지역 이스라엘과 아랍국가들 간의 관계, 냉전기 미소관계, 인도-파키스탄 및 남북한 관계 등을 예로 들 수 있다. 이렇게 널리 알려진 숙적관계 외에도 남미의 칠레-아르헨티나, 에콰도르-페루와 아프리카의 소말리아-에티오피아 등 학자들에 따라 1815년 이후 약 200개의 숙적관계를 제시하고 있다. 숙적관계에 대한 연구는 기존의 전쟁의 원인 중심이었던 정량적 국제분쟁 연구에 두 국가의 분쟁역사를 포함시키는 정성적 연구를 접합시키고 있다. 본 연구는 1945년 이후 숙적관계 국가들의 관계종식과 관련하여, 거시론적이고 전체론적 접근방법(Macro - level Holistic Approach)을 제시하고 있다. 먼저 1945년 이후 발생한 국가들 간의 숙적관계 종식(Rivalry Termination)을 이해하기 위해, 거시적 관점에서 숙적관계를 발생시키게 된 역사적 원인을 살펴보고 있다. 특히 1945년 이후 숙적관계와 관련된 중요한 요인들 중에서 전쟁, 영토분쟁, 그리고 근대국가 형성에 대해 살펴보고 다음과 같은 두 가지 명제(proposition)를 제시한다. 첫째, 1945년 이후의 숙적관계 형성과 지속에는 2차대전 이후 독립국가 형성, 헌팅턴이 주장한 제3의 물결(민주화), 그리고 냉전기 미소경쟁 등의 역사적 배경이 영향을 주었다는 것이다. 둘째, 이러한 역사적 배경에 더하여 1945년 이후 숙적관계는 전쟁에 의해 시작된 숙적관계와 전쟁 없이 시작된 숙적관계 등 2가지로 나눌 수 있으며, 전쟁에 의해 시작되고 영토분쟁과 근대국가 형성 문제를 내포하고 있는 숙적관계가 그렇지 않은 숙적관계에 비해 오랫동안 지속되며 관계해결이 어렵다는 것이다. 앞서 제시된 2가지 명제들과 관련하여 본문에서는 다양한 학자들이 제시한 숙적관계 정의들에 일치하는 23개의 숙적관계(Consensus Rivalries)를 선정하여 이들에 대한 비교분석(Descriptive Analysis)을 실시하였다. 이들 사례들을 1945년 이전과 이후로 나누어, 숙적관계 형성과 종식에 있어 핵심요소인 국가들 간 힘의 차이(Power Relations), 분쟁의 주요 원인(Primary Conflict Issue), 숙적관계에 있어 다른 국가들과의 연계성(Rivalry Linkage), 전쟁의 횟수와 시기 등을 통해 비교하였다. 숙적관계의 종식과 관련하여 약소국 간의 숙적관계(Minor Dyad)가 오래 지속되고, 영토분쟁(Territorial Disputes)이 숙적관계를 지속시키는 주요인이며, 다른 숙적관계와의 연계성이 적은 숙적들이 오래 지속된다는 비교분석 결과가 나왔다. 또한 전쟁의 횟수는 숙적관계 종식에 큰 영향을 미치지 못하지만 전쟁으로 인해 시작된 숙적관계가 그렇지 않은 경우보다 더욱 오래 지속되는 것으로 확인되었다. 끝으로 2차대전 이전의 숙적관계는 대부분 전쟁을 통해 종식되었지만, 1945년 이후에는 전쟁 없이도 숙적관계가 종식된 경우가 많았음을 보여 주고 있다. 본 연구의 주목적은 "1945년 이후 형성된 숙적관계를 어떻게 종식시킬 수 있을 것인가?"라는 규범적 논제를 통해, 23개의 주요 숙적관계를 발굴하여 거시적, 역사적 관점에서 비교분석함에 있다. 이는 특히 우리나라가 처한 현실과 관련하여 중요한 시사점을 갖는다. 남북관계가 갖는 특수성보다는 1945년 이후 국제정치 역사속에서 발생한 숙적관계 현상이라는 일반성의 틀에서 남북관계를 이해하고자 했다. 남북관계를 베트남, 예멘, 독일 등 분단국가의 사례들과만 비교 연구하는 제한된 시각에서 벗어나, 인도-파키스탄, 그리스-터키, 에콰도르-페루 등 유사한 숙적들 간의 관계들과 비교하는 새로운 연구의 장을 제시하고자 한다. 따라서 앞으로 숙적관계 종식에 대한 더욱 다양화된 사례연구를 통해 한반도 분쟁해결에 필요한 새로운 교훈을 얻을 수 있을 것이다. 예를 들면 2차대전 이후 발생한 국경을 접하고 있는 비강대국들의 평화적인 숙적관계 종식에 대한 사례연구는 남북한이 앞으로 지향해야 할 방향을 제시해 줄 수 있을 것이다. 끝으로 본 연구는 특정한 정책적 함의를 도출하기 보다는 숙적관계와 관련된 하나의 거시적 이론를 제시하고, 주요 숙적관계 국가들에 대한 비교설명을 통해 현존하는 숙적관계 해결을 위한 하나의 분석의 틀을 제시하는 것으로 국제분쟁 연구에 기여하고자 하였다.