• Title/Summary/Keyword: importance of system

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Ecological Importance of Water Budget and Synergistic Effects of Water Stress of Plants due to Air Pollution and Soil Acidification in Korea (한국에서 수분수지의 생태적 중요성과 대기오염 및 토양 산성화로 인한 식물의 수분스트레스 증대 효과)

  • 이창석;이안나
    • The Korean Journal of Ecology
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    • v.26 no.3
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    • pp.143-150
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    • 2003
  • Korea has plentiful precipitation but rainfall events concentrate on several months of rainy season in her weather condition. Korea, therefore, experiences drought for a given period every year. Moreover the soil has usually low water holding capacity, as it is composed coarse particles originated from the granite. Response of several oaks and the Korean red pine (Pinus densiflora) on water stress showed that water budget was significant factor determining vegetation distribution. In addition, dehydration level due to cold resistance mechanism of several evergreen plants during the winter season was closely related to their distribution in natural condition. Experimental result under water stress showed that the Korean red pine was very tolerant to desiccation but the seedlings showed high mortality during the dry season. The mortality tended to proportionate to soil moisture content of each site. A comparison between soil moisture content during June when it is severe dry season and moisture content of the culture soil when the pine seedlings reached the permanent wilting point due to water withheld proved that high mortality during the dry season was due to water deficit. Water potential of sample plants measured during the exposure experiment to the air pollutant showed a probability that water related factors would dominate the occurrence of visible damage and the tolerance level of sample plants. In both field survey and laboratory experiment, plants exposed to air pollution showed more rapid transpiration than those grown in the unpolluted condition. The result would due to injury of leaf surface by air pollutants. Aluminum (Al/sup 3+/) increased in the acid soil not only inhibits root growth but also leads to abnormal distribution of root system and thereby caused water stress. The water stresses due to air pollution and soil acidification showed a possibility that they play dominating roles in inducing forest decline additionally to the existing water deficit due to weather and soil conditions in Korea. Sludge, which can contribute to improve field capacity, as it is almost composed of organic matter, showed an effect ameliorating the retarded growth of plant in the acidified soil. The effect was not less than that of dolomite known in widely as such a soil ameliorator. Litter extract contributed also to mitigate the water stress due to toxic Al/sup 3+/. We prepared a model showing the potential interaction of multiple stresses, which can cause forest decline in Korea by synthesizing those results. Furthermore, we suggested restoration plans, which can mitigate such forest decline in terms of soil amelioration and vegetation restoration.

Food Sources of the Ascidian Styela clava Cultured in Suspension in Jindong Bay of Korea as Determined by C and N Stable Isotopes (탄소 및 질소안정동위원소 조성에 의한 남해안 진동만 양식 미더덕의 먹이원 평가)

  • Moon, Changho;Park, Hyun Je;Yun, Sung Gyu;Kwak, Jung Hyun
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.19 no.4
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    • pp.302-307
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    • 2014
  • To examine the trophic ecology of the ascidian Styela clava in an aquaculture system of Korea, stable carbon and nitrogen isotopes were analyzed monthly in S. clava, coarse ($>20{\mu}m$, CPOM) and fine particulate organic matters ($0.7<<20{\mu}m$, FPOM). CPOM (means: $-18.5{\pm}1.2$‰, $9.3{\pm}0.7$‰) were significantly higher ${\delta}^{13}C$ and ${\delta}^{15}N$ values than those ($-20.5{\pm}1.5$‰, $8.4{\pm}0.5$‰) of FPOM. S. clava had mean ${\delta}^{13}C$ and ${\delta}^{15}N$ values of $-18.9({\pm}1.7)$‰ and $11.6({\pm}0.7)$‰, respectively. S. clava were more similar to seasonal variations in ${\delta}^{13}C$ and ${\delta}^{15}N$ values of FPOM than those of CPOM, suggesting that they rely largely on the FPOM as a dietary source. In addition, our results displayed that the relative importance between CPOM and FPOM as dietary source for the ascidians can be changed according to the availability of each component in ambient environment, probably reflecting their feeding plasticity due to non-selective feeding irrespective of particle size. Finally, our results suggest that dynamics of pico- and nano-size plankton (i.e., FPOM) as an available nutritional source to S. clava should be effectively assessed to maintain and manage their sustainable aquaculture production.

Geosites, Geoheritages and Geotrails of the Hwaseong Geopark, the Candidate for Korean National Geopark (화성 국가지질공원 후보지의 지질명소, 지질유산 그리고 지오트레일)

  • Cho, Hyeongseong;Shin, Seungwon;Kang, Hee-Cheol;Lim, Hyoun Soo;Chae, Yong-Un;Park, Jeong-Woong;Kim, Jong-Sun;Kim, Hyeong Soo
    • The Journal of the Petrological Society of Korea
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    • v.28 no.3
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    • pp.195-215
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    • 2019
  • Geopark is a new system for development of the local economy through conservation, education, and tourism that is an area of scientific importance for the earth sciences and that has outstanding scenic values. The Hwaseong Geopark, the candidate for Korean National Geopark is composed of 10 geosites: Gojeongri dinosaur egg fossils, Ueumdo, Eoseom, Ddakseom, Goryeom, Jebudo, Baengmiri Coast, Gungpyeonhang, Ippado and Gukwado geosites. In this study, geosites, geoheritages, and geotrails of the Hwaseong Geopark were described in detail, and the value and significane as a geopark were also discussed. The geology of the Hwaseong Geopark area belonging to the Gyeonggi Massif consists of the Precambrian metamorphic and meta-sedimentary rocks, Paleozoic sedimentary and metamorphic rocks, Mesozoic igneous and sedimentary rocks, and Quaternary deposits, indicating high geodiversity. The Gojeongri Dinosaur Egg Fossils geosite, designated as a natural monument, has a geotrail including dinosaur egg nest fossils, burrows, tafoni, fault and drag fold, cross-bedding. Furthermore, a variety of infrastructures such as eco-trail deck, visitor center are well-established in the geosite. In the Ueumdo geosite, there are various metamorphic rocks (gneiss, schist, and phyllite) and geological structures (fold, fault, joint, dike, and vein), thus it has a high educational value. The Eoseom geosite has high academic value because of the orbicular texture found in metamorphic rocks. Also, various volcanic and sedimentary rocks belonging to the Cretaceous Tando Basin can be observed in the Ddakseom and Goryeom geosites. In the Jebudo, Baengmiri Coast, and Gungpyeonghang geosites, a variety of coastal landforms (tidal flat, seastacks, sand and gravel beach, and coastal dunes), metamorphic rocks and geological structures, such as clastic dikes and quartz veins can be observed, and they also provide various programs including mudflat experience to visitors. Ippado and Gukwado geosites have typical large-scale fold structures, and unique coastal erosional features and various Paleozoic schists can be observed. The Hwaseong Geopark consists of outstanding geosites with high geodiversity and academic values, and it also has geotrails that combine geology, geomorphology, landscape and ecology with infrastructures and various education and experience programs. Therefore, the Hwaseong Geopark is expected to serve as a great National Geopark representing the western Gyeonggi Province, Korea.

The Jurisdictional Precedent Analysis of Medical Dispute in Dental Field (치과임상영역에서 발생된 의료분쟁의 판례분석)

  • Kwon, Byung-Ki;Ahn, Hyoung-Joon;Kang, Jin-Kyu;Kim, Chong-Youl;Choi, Jong-Hoon
    • Journal of Oral Medicine and Pain
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    • v.31 no.4
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    • pp.283-296
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    • 2006
  • Along with the development of scientific technologies, health care has been growing remarkably, and as the social life quality improves with increasing interest in health, the demand for medical service is rapidly increasing. However, medical accident and medical dispute also are rapidly increasing due to various factors such as, increasing sense of people's right, lack of understanding in the nature of medical practice, over expectation on medical technique, commercialize medical supply system, moral degeneracy and unawareness of medical jurisprudence by doctors, widespread trend of mutual distrust, and lack of systematized device for solution of medical dispute. This study analysed 30 cases of civil suit in the year between 1994 to 2004, which were selected among the medical dispute cases in dental field with the judgement collected from organizations related to dentistry and department of oral medicine, Yonsei university dental hospital. The following results were drawn from the analyses: 1. The distribution of year showed rapid increase of medical dispute after the year 2000. 2. In the types of medical dispute, suit associated with tooth extraction took 36.7% of all. 3. As for the cause of medical dispute, uncomfortable feeling and dissatisfaction with the treatment showed 36.7%, death and permanent damage showed 16.7% each. 4. Winning the suit, compulsory mediation and recommendation for settlement took 60.0% of judgement result for the plaintiff. 5. For the type of medical organization in relation to medical dispute, 60.0% was found to be the private dental clinics, and 30.0% was university dental hospitals. 6. For the level of trial, dispute that progressed above 2 or 3 trials was of 30.0%. 7. For the amount of claim for damage, the claim amounting between 50 million to 100 million won was of 36.7%, and that of more than 100 million won was 13.3%, and in case of the judgement amount, the amount ranging from 10 million to 30 million won was of 40.0%, and that of more than 100 million won was of 6.7%. 8. For the number of dentist involved in the suit, 26.7% was of 2 or more dentists. 9. For the amount of time spent until the judgement, 46.7% took 11 to 20 months, and 36.7% took 21 to 30 months. 10. For medical malpractice, 46.7% was judged to be guilty, and 70% of the cases had undergone medical judgement or verification of the case by specialists during the process of the suit. 11. In the lost cases of doctors(18 cases), 72.2% was due to violence of carefulness in practice and 16.7% was due to missing of explanation to patient. Medical disputes occurring in the field of dentistry are usually of relatively less risky cases. Hence, the importance of explanation to patient is emphasized, and since the levels of patient satisfaction are subjective, improvement of the relationship between the patient and the dentist and recovery of autonomy within the group dentist are essential in addition to the reduction of technical malpractice. Moreover, management measure against the medical dispute should be set up through complement of the current doctors and hospitals medical malpractice insurance which is being conducted irrationally, and establishment of system in which education as well as consultation for medical disputes lead by the group of dental clinicians and academic scholars are accessible.

Analysis of Aquifer Test Data in Fractured Aquifers and the Application of the Generalized Radial Flow (균열암반에서의 양수시험자료 해석과 일반 방사상 유동모델의 적용성 연구)

  • Seong Hyeonjeong;Kim Yongie;Lee Chul-Woo;Kim Kue-Young;Woo Nam-Chil
    • Economic and Environmental Geology
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    • v.38 no.2 s.171
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    • pp.177-185
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    • 2005
  • Data from 122 pumping tests were obtained from 100 boreholes in granites, volcanic rocks, metamorphic rocks, and Cretaceous and Tertiary sedimentary rocks, and then were analyzed using AQTESOLV. Results from 86 of the 122 tests ($71\%$) have an analytical solution corresponding to Theis (1935), Cooper-Jacob (1946), Papadopulos-Cooper (1967), Hantush (1962), Moench (1985), or Hantush-Jacob (1955), whereas the remaining 36 results ($29.5\%$) do not correspond to any of the analytical methods. Of the 86 results, only 17 match the Theis and Cooper-Jacob methods, indicating that the basic methods fer pumping test analysis are useful far only $14\%$ of the total data. This suggests that analytical solutions derived using leaky boundary conditions are appropriate for the analysis of pumping test data in fractured aquifers in this study. Furthermore, the results show the importance of carefully selecting an appropriate model for the analysis of pumping test data. Results from the 122 pumping tests were also analyzed using the GRF model. Using the Barker method, the results show that 77 of the 122 tests ($63\%$) have dimensions ranging between 1.1-2.9. Of these 77 solutions, ($39(44.2{\%})$) have a fractional dimension of 1.1-1.9, ($26(6.5{\%})$) show 2-dimensional radial flow also applicable to the Theis method, and ($38(49.3{\%})$) have dimensions of 2.1-2.9. The results show that groundwater flows according to a fractional flow dimension in fractured aquifers.

Community Dwellers' Perception of Past Life Recollection and Preparation for Death (서울시 일 지역 주민의 인생회고 및 죽음준비 인식)

  • Kang, Kyung-Ah;Lee, Kyung-Soon;Park, Gang-Won;Kim, Yong-Ho;Jang, Mi-Ja;Lee, Eun
    • Journal of Hospice and Palliative Care
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    • v.14 no.2
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    • pp.81-90
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    • 2011
  • Purpose: This study is to understand how community members perceive past life recollection and preparation for death. Methods: Using a questionnaire, we surveyed 160 adult residents of one of the districts (gu) in Seoul, Korea. Descriptive statistics were used. Results: Participants chose their 30s and 40s as the most difficult time in their lives. The most painful experience was "an illness of a family member", followed by "trouble with a spouse", and "trouble with children". As for the most difficult social experience, "sense of loss in life" was ranked the highest. Personally, the happiest time was "accomplishment of a goal", while it was "happiness through children" in family relationship and "contribution to society through my career" in social life. As for the most regrettable experience, personally "having lived without purpose" was the highest, "not meeting my parents' expectation more" in family relationship; "not providing sufficient education" in relationship with children; "not having an occupation that I wanted" in work life, and "lack of social skills" in social life. More than 87% of the surveyed showed a positive attitude about the system of the do not resuscitate (DNS) order. For a situation where participants were supposed to have an incurable disease, "I want to be notified of the true condition" and "I want to write a will and advanced directives" ranked high, receiving more than 3.1 points out of 4. Conclusion: These results demonstrate the need for death education to provide people with an opportunity to accept their regrettable experiences in the past as part of their life. Also, this study suggests the importance of writing advanced directives for people to prepare for "death with dignity" how it can help their decision to be better respected.

Nammyeong Jo-Sik's Practical Social Reformism (남명 조식의 현실적 사회개혁론 - 경(敬)·의(義)를 중심으로 -)

  • Lee, mi rim
    • The Journal of Korean Philosophical History
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    • no.39
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    • pp.29-52
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    • 2013
  • Philosophy of respect righteousness advocated by Nammyung points to what first needs to be done to drive social changes. It is consistent with the Confucianism, which views the world from within oneself. After all, developing a proper view of the society starts from looking at oneself in the right perspective. The view that personal cultivation can develop into cultivation and eventually reform of the entire society is also present in Confucius' belief that one can only be at peace after disciplining oneself and observe good manners only after perseverance. Also, one can lead the world in peace only after disciplining one's body and mind. In other words, it suggests that individuals and the community where they belong to are not independent from one another. Rather, individuals gather to create a society and righteous individuals are the basis for righteous society. These principles of social system in Confucianism can be understood as a mutual or layered division and integration. The society is not conflicted with individuals or the nation but rather perceived as moral communities to co-exist. Hence, power of execution observed in the philosophy of respect and righteousness by Nammyung is identical to power of execution applied to the society. The power of execution shows up as 'the execution of righteousness' in Nammyung's philosophy of respect and righteousness. It is also demonstrated in the acts by Nammyung's disciples when the nation was at crisis. This is what differentiates Nammyung's new-Confucianism in Joseon Dynasty from Toegye or Yulgok as he tried to deliver 'the execution of righteousness.' It does not mean that neo-Confucian scholars did not emphasize the importance of execution, but Nammyung, in particular, warned how deceitful ideological or inner-directed thinking can be since they fail to come up with concrete solutions to social issues. In summary, Nammyung's moral discipline and training based on respect and righteousness cannot be evaluated in a state of vacuum separate from social and historical aspects but under the context of enlightening virtue and social execution. This can draw the conclusion that Nammyung's execution of respect and righteousness is in the starting point of the realistic 'theory of social reform' for creating a better world.

The Prediction of Export Credit Guarantee Accident using Machine Learning (기계학습을 이용한 수출신용보증 사고예측)

  • Cho, Jaeyoung;Joo, Jihwan;Han, Ingoo
    • Journal of Intelligence and Information Systems
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    • v.27 no.1
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    • pp.83-102
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    • 2021
  • The government recently announced various policies for developing big-data and artificial intelligence fields to provide a great opportunity to the public with respect to disclosure of high-quality data within public institutions. KSURE(Korea Trade Insurance Corporation) is a major public institution for financial policy in Korea, and thus the company is strongly committed to backing export companies with various systems. Nevertheless, there are still fewer cases of realized business model based on big-data analyses. In this situation, this paper aims to develop a new business model which can be applied to an ex-ante prediction for the likelihood of the insurance accident of credit guarantee. We utilize internal data from KSURE which supports export companies in Korea and apply machine learning models. Then, we conduct performance comparison among the predictive models including Logistic Regression, Random Forest, XGBoost, LightGBM, and DNN(Deep Neural Network). For decades, many researchers have tried to find better models which can help to predict bankruptcy since the ex-ante prediction is crucial for corporate managers, investors, creditors, and other stakeholders. The development of the prediction for financial distress or bankruptcy was originated from Smith(1930), Fitzpatrick(1932), or Merwin(1942). One of the most famous models is the Altman's Z-score model(Altman, 1968) which was based on the multiple discriminant analysis. This model is widely used in both research and practice by this time. The author suggests the score model that utilizes five key financial ratios to predict the probability of bankruptcy in the next two years. Ohlson(1980) introduces logit model to complement some limitations of previous models. Furthermore, Elmer and Borowski(1988) develop and examine a rule-based, automated system which conducts the financial analysis of savings and loans. Since the 1980s, researchers in Korea have started to examine analyses on the prediction of financial distress or bankruptcy. Kim(1987) analyzes financial ratios and develops the prediction model. Also, Han et al.(1995, 1996, 1997, 2003, 2005, 2006) construct the prediction model using various techniques including artificial neural network. Yang(1996) introduces multiple discriminant analysis and logit model. Besides, Kim and Kim(2001) utilize artificial neural network techniques for ex-ante prediction of insolvent enterprises. After that, many scholars have been trying to predict financial distress or bankruptcy more precisely based on diverse models such as Random Forest or SVM. One major distinction of our research from the previous research is that we focus on examining the predicted probability of default for each sample case, not only on investigating the classification accuracy of each model for the entire sample. Most predictive models in this paper show that the level of the accuracy of classification is about 70% based on the entire sample. To be specific, LightGBM model shows the highest accuracy of 71.1% and Logit model indicates the lowest accuracy of 69%. However, we confirm that there are open to multiple interpretations. In the context of the business, we have to put more emphasis on efforts to minimize type 2 error which causes more harmful operating losses for the guaranty company. Thus, we also compare the classification accuracy by splitting predicted probability of the default into ten equal intervals. When we examine the classification accuracy for each interval, Logit model has the highest accuracy of 100% for 0~10% of the predicted probability of the default, however, Logit model has a relatively lower accuracy of 61.5% for 90~100% of the predicted probability of the default. On the other hand, Random Forest, XGBoost, LightGBM, and DNN indicate more desirable results since they indicate a higher level of accuracy for both 0~10% and 90~100% of the predicted probability of the default but have a lower level of accuracy around 50% of the predicted probability of the default. When it comes to the distribution of samples for each predicted probability of the default, both LightGBM and XGBoost models have a relatively large number of samples for both 0~10% and 90~100% of the predicted probability of the default. Although Random Forest model has an advantage with regard to the perspective of classification accuracy with small number of cases, LightGBM or XGBoost could become a more desirable model since they classify large number of cases into the two extreme intervals of the predicted probability of the default, even allowing for their relatively low classification accuracy. Considering the importance of type 2 error and total prediction accuracy, XGBoost and DNN show superior performance. Next, Random Forest and LightGBM show good results, but logistic regression shows the worst performance. However, each predictive model has a comparative advantage in terms of various evaluation standards. For instance, Random Forest model shows almost 100% accuracy for samples which are expected to have a high level of the probability of default. Collectively, we can construct more comprehensive ensemble models which contain multiple classification machine learning models and conduct majority voting for maximizing its overall performance.

Timing and Risk Factors of Adoption for Legally-Free Foster Children after Having Parental Rights Terminated in the U. S. (미국 위탁아동의 친권상실선고 이후 입양 결정요인에 관한 생존분석)

  • Song, Min-Kyoung
    • Korean Journal of Social Welfare
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    • v.59 no.1
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    • pp.301-327
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    • 2007
  • The purpose of this study is to examine the timing and the risk factors associated with the adoption of legally-free foster children. The sample of the study was drawn from foster care files of Adoption and Foster Care Analysis and Reporting System(AFCARS) in 32 states between October 1998 (FY 1999) and September 2002(FY 2002). The timing post-TPR to adoption was examined by plotting the Kaplan-Meier cumulative hazard function for adoption and by plotting the KM hazard functions stratified by child's race and child's age at TPR. Cox proportional-hazards regression analysis was used to identify risk factors for adoption of legally-free foster children after TPR. The hazard of adoption was very low immediately after TPR but increased steadily starting at 3 months and then declined after 20 months. The cumulative hazard functions for White non-Hispanic children and Black non-Hispanic children crossed over at 13 months after TPR. Racial minority status, older age, and disability were negatively associated with the hazard of adoption. Physical abuse, sexual abuse had the lower hazard for adoption compared by neglect. Caretaker's inability to cope had the slightly lower hazard for adoption whereas inadequate housing showed the slightly greater hazard for adoption. Characteristics of foster care services turned into be powerful predictors of adoption. Specifically, legally-free children placed in pre-adoptive homes, those who shared the same racial/ethnic background with their foster caretakers, and those who were placed in two-parent families have a greater likelihood of adoption. The findings highlight the importance of foster care service provisions after TPR to facilitate adoption of legally-free foster children. Furthermore, a more substantial resources and targeted support for foster children who experience physical abuse and sexual abuse in need of adoption should be provided for moving the foster children into permanency.

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A Study on the Policy Proposal for the Expansion of Design Utilization in the Public Sector : Focused on the Case of the National Design Group (공공분야 디자인 활용 확대를 위한 정책제안 연구: 국민디자인단 사례를 중심으로)

  • Bang, Songhee;Kim, Taewan
    • Journal of Service Research and Studies
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    • v.13 no.3
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    • pp.160-171
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    • 2023
  • The importance of design utilization as a method for establishing policies and services in the public sector is increasing. Accordingly, Korea has introduced a public service design development method and has implemented and operated a national design group for consumer-centered policy development since 2014. This study analyzes the cases of the National Design Group to expand the use of design in the public sector and propose sustainable public service design strategies. The time range of this study is from 2014 to 2021, when the National Design Group was implemented, and the content is limited to tasks that can be found on the Gwanghwamun 1st Street website and the National Design Group casebook. This study was conducted as follows. First, we looked for implications for how to use and identify the role of design in the public policy development stage by referring to the literature on design policy and public service design, and second, based on major implications, we analyzed the task name and contents. Based on literature studies and case studies, we found implications that design can be used in various public fields, and the policy implications proposed to expand the use of sustainable design in the public sector are as follows. First, by raising awareness of service design in public policies and services, it continues to provide opportunities for the use of design to expand as a role that leads to voluntary behavioral changes of citizens beyond civic participation. Second, more active publicity is needed for the successful cases of the National Design Group, a product of the active use of public service design. Third, a more specific evaluation system should be introduced to verify the effectiveness and effectiveness of public service design. Through this, it is expected that it will greatly contribute to reducing the error in policy delivery and realizing citizen-centered public services by utilizing design for various problems facing our society.