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The Variations of Stratospheric Ozone over the Korean Peninsula 1985~2009 (한반도 상공의 오존층 변화 1985~2009)

  • Park, Sang Seo;Kim, Jhoon;Cho, Nayeong;Lee, Yun Gon;Cho, Hi Ku
    • Atmosphere
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    • v.21 no.4
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    • pp.349-359
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    • 2011
  • The climatology in stratospheric ozone over the Korean Peninsula, presented in previous studies (e.g., Cho et al., 2003; Kim et al., 2005), is updated by using daily and monthly data from satellite and ground-based data through December 2009. In addition, long-term satellite data [Total Ozone Mapping Spectrometer (TOMS), Ozone Monitoring Instrument (OMI), 1979~2009] have been also analyzed in order to deduce the spatial distributions and temporal variations of the global total ozone. The global average of total ozone (1979~2009) is 298 DU which shows a minimum of about 244 DU in equatorial latitudes and increases poleward in both hemispheres to a maximum of about 391 DU in Okhotsk region. The recent period, from 2006 to 2009, shows reduction in total ozone by 6% relative to the values for the pre-1980s (1979~1982). The long-term trends were estimated by using a multiple linear regression model (e.g., WMO, 1999; Cho et al., 2003) including explanatory variables for the seasonal variation, Quasi-Biennial Oscillation (QBO) and solar cycle over three different time intervals: a whole interval from 1979 to 2009, the former interval from 1979 to 1992, and the later interval from 1993 to 2009 with a turnaround point of deep minimum in 1993 is related to the effect of Mt. Pinatubo eruption. The global trend shows -0.93% $decade^{-1}$ for the whole interval, whereas the former and the later interval trends amount to -2.59% $decade^{-1}$ and +0.95% $decade^{-1}$, respectively. Therefore, the long-term total ozone variations indicate that there are positive trends showing a recovery sign of the ozone layer in both North/South hemispheres since around 1993. Annual mean total ozone (1985~2009) is distributed from 298 DU for Jeju ($33.52^{\circ}N$) to 352 DU for Unggi ($42.32^{\circ}N$) in almost zonally symmetric pattern over the Korean Peninsula, with the latitudinal gradient of 6 DU $degree^{-1}$. It is apparent that seasonal variability of total ozone increases from Jeju toward Unggi. The annual mean total ozone for Seoul shows 323 DU, with the maximum of 359 DU in March and the minimum of 291 DU in October. It is found that the day to day variability in total ozone exhibits annual mean of 5.7% in increase and -5.2% in decrease. The variability as large as 38.4% in increase and 30.3% in decrease has been observed, respectively. The long-term trend analysis (e.g., WMO, 1999) of monthly total ozone data (1985~2009) merged by satellite and ground-based measurements over the Korean Peninsula shows increase of 1.27% $decade^{-1}$ to 0.80% $decade^{-1}$ from Jeju to Unggi, respectively, showing systematic decrease of the trend magnitude with latitude. This study also presents a new analysis of ozone density and trends in the vertical distribution of ozone for Seoul with data up to the end of 2009. The mean vertical distributions of ozone show that the maximum value of the ozone density is 16.5 DU $km^{-1}$ in the middle stratospheric layer between 24 km and 28 km. About 90.0% and 71.5% of total ozone are found in the troposphere and in the stratosphere between 15 and 33 km, respectively. The trend analysis reconfirms the previous results of significant positive ozone trend, of up to 5% $decade^{-1}$, in the troposphere and the lower stratosphere (0~24 km), with negative trend, of up to -5% $decade^{-1}$, in the stratosphere (24~38 km). In addition, the Umkehr data show a positive trend of about 3% $decade^{-1}$ in the upper stratosphere (38~48 km).

An Influence of the Source Information of Word Mouth on the Sales of Educational Service (구전의 정보원천이 교육서비스 판매에 미치는 영향)

  • Kang, Gye-Young;Song, In-Am;Hwang, Hee-Joong
    • Journal of Distribution Science
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    • v.9 no.2
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    • pp.73-81
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    • 2011
  • This study is designed to examine the effects of information source effects of the word mouth have on the formed expectations for the private institution and to explore the formed expectations' effects on the actual sales of the educational service. Moreover, its purpose is in analyzing what medication effects the pre-conceived expectation has on selecting the educational service. After testing hypothesis, the results showed that the source effects of the information from word of mouth had a significant effect on the expectation factors, in terms of expertise, similarity, likability and familiarity expectation factors. However, it was found that effect was not significant for the truthfulness. The significant result was found on the expectation factors before visiting the private institution on selecting educational service, indicating a positive effect. As for the influence of source of the word of mouth information on selecting educational service, the results from the mediation effects of the expectation factors on selecting the educational service showed that for expectation factors, expertise had the partial mediation effect, truthfulness, perfect mediating effect, similarity, partial mediation effect, likability, perfect mediating effect, and familiarity, perfect mediating effect. A test of the mediating role of attribute expectations in the influence of WOM message source attributes on educational services choices showed the following: 1) It was proven that attribute expectations played a partial mediating role in the influence of expertise and similarity, respectively, on educational services choices. 2) On the influence of trustworthiness, likability, and familiarity on educational services choices, respectively, attribute expectations had a full mediation effect. This research differs from the previous ones, which focused only on consumer satisfaction with educational services offered by private educational institutions in that it covers not only the influences of both WOM source attributes and key component factors of educational services on both educational services choices and satisfaction with such services but also the influence of WOM source attributes on attribute expectations prior to the first visit to a particular private educational institutions, and in turn the influence of such attribute expectations on educational services choices. Most particularly, the significance of this study lies in the fact that in an effort to more clearly explain the causal relationship between WOM source effects and educational services choices a test of the mediating role of attribute expectations was conducted. Although the research seems simple, some theoretical implications can be drawn as follows: WOM message source effects on educational services choices were positive and moreover these positive impacts are likely to be reinforced by means of the mediating variable of attribute expectations.

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Characteristics of Water Quality Parameters of Han River Related to THMs Formation in Water Treatment Plants in Seoul (서울시 정수장의 THMs 생성과 관련된 한강 원수의 주요 수질 특성 조사)

  • Lee, Jin-Hyo;Lee, Ki-Seon;Hwang, Dong-Hyun;Lee, Man-Ho;Han, Sun-Hee;Park, Yong-Sang;Lee, Mok-Young;Lee, Jin-Sook;Koo, Ja-Yong
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.12
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    • pp.886-892
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    • 2011
  • In a study on THMs formation at the distribution facilities in Seoul water supply for past 3 years from 2007 to 2009, THMs production was increased from inlet to outlet during the process in water treatment plant. However, such increased THMs amount was very small compared to THMs production formed after pre-chlorination and post chlorination. Accordingly, this study is aimed to investigate the characteristics of water quality parameters of Han River related to THMs formation in 6 water treatment plants in Seoul. The results showed that THMs and other factors such as temperature (r = 0.539~0.846) and turbidity (r = 0.421~0.863) had positive correlation while THMs had negative correlation with pH (r = -0.613~-0.800) and algae (r = -0.582~-0.901). There is no correlation between THMs and $NH_3-N$. According to the factor analysis, generally metabolite and organic matter factor $X_1$ (pH, BOD, algae), and seasonal and natural factor $X_2$ (temperature, turbidity) played an important role in the formation of THMs. Multiple regression analysis for THMs formation showed significance of regression appeared in most water systems.

Immunocytochemical Localization of Parvalbumin and Calbindin-D 28K in Monkey Dorsal Lateral Geniculate Nucleus (원숭이 외측슬상체배측핵에서 칼슘결합단백 Parvalbumin과 Calbindin-D 28K의 분포)

  • Ko, Seung-Hee;Bae, Choon-Sang;Park, Sung-Sik
    • Applied Microscopy
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    • v.24 no.4
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    • pp.61-77
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    • 1994
  • The calcium-binding proteins (CaBP), parvalbumin (PV) and calbindin-D 28K (calbindin) are particularly abundant and specific in their distribution, and present in different subsets of neurons in many brain regions. Although their physiological roles in the neurons have not been elucidated, they are valuable markers of neuronal subpopulations for anatomical and developmental studies. This study is designed to characterize dorsal lateral geniculate nucleus (dLGN) neurons and axon terminals in terms of differential expression of immunoreactivity (IR) for two well-known CaBPs, PV and calbindin. The experiments were carried out on 6 adult monkeys. Monkeys were perfused under deep Nembutal anesthesia with 2% paraformaldehyde and 0.2% glutaraldehyde in 0.1M phosphate buffer. After removal, the brains were postfixed for 6-8 hr in 2% paraformaldehyde at $4^{\circ}C$ and infiltrated with 30% sucrose at $4^{\circ}C$. Thereafter, they were frozen in dry ice. Serial sections of the thalamus, at $20{\mu}m$, were made in the frontal plane with a sliding microtome. The sections were stained for PV and calbindin with indirect immunocytochemical methods. For electron microscopy, after infiltration with 30% sucrose the blocks of thalamus were serially sectioned at $50{\mu}m$ with a Vibratome in the coronal plane and stained immediately by indirect ABC methods without Triton X-100 in incubation medium. Stained sections were postfixed in 0.2% osmium tetroxide, dehydrated and flat-embedded in Spurr resin. The block was then trimmed to contain only a selected lamina or interlaminar space. The dLGN proper showed strong PV IR in fibers in all laminae and interlaminar zones. Particularly dense staining was noted in layers 1 and 2 that contain many stained fibers from optic tract. Neuronal cell body stained with PV was concentrated only in the laminae. In these laminae staining was moderate in cell bodies of all large and medium-sized neurons, and was strong in cell bodies of some small neurons together with their processes. Calbindin IR was marked in the neuronal cell body and neuropil in the S layers and interlaminar zones whereas moderate in the neuropil throughout the nucleus. Regional difference in distribution of PV and calbindin IR cell is distinct; the former is only in the laminae and the latter in both the S layer and interlaminar space. The CaBP-IR elements were confined to about $10{\mu}m$ in depth of Vibratome section. The IR product for CaBP was mainly associated with synaptic vesicle, pre- and post-synaptic membrane, and outer mitochondrial membrane and along microtubule. PV-IR was noted in various neuronal elements such as neuronal soma, dendrite, RLP, F, PSD and some myelinated or unmyelinated axons, and was not seen in the RSD and glial cells. Only a few neuronal components in dLGN was IR for calbindin and its reaction product was less dense than that of PV, and scattered throughout cytoplasm of soma of some relay neurons, and was also persent in some dendrite, myelinated axons and RLP. The RSD, F, PSD and glial elements were always non-IR for calbindin. Calbindin labelled RLP were presynaptic to unlabeled dendrite or dendritic spine and PSD. Calbindin-labeled dendrite of various sizes were always postsynaptic to unlabeled RSD, RLP or F. From this study it is suggested that dLGN cells of different functional systems and their differential projection to the visual cortex can be distinguished by differential expression of PV and calbindin.

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Clinical Characteristics of Miliary Tuberculosis (속립성 폐결핵의 임상적 특성)

  • Kim, Jin-Ho;Moon, Doo-Seop;Lee, Dong-Suck;Park, Ik-Soo;Yoon, Ho-Joo;Shin, Dong-Ho;Kim, Tae-Wha;Park, Sung-Soo;Lee, Jung-Hee
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.2
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    • pp.144-151
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    • 1994
  • Background: Miliary tuberculosis almost always results from the discharge of infected caseous material into the blood stream, usually from a well hidden lymph node in the presentation of this disease in the past four decades, and although it is seen less frequent1y today than previously, its presentation and manifestation may require greater suspicion and diligence by the physician. We investigated the clinical characteristics, predisposing factors and accompanying diseases of miliary tuberculosis and tried to acquire the early diagnosis and treatment of this disease. Methods: A retrospective clinical study was done on 40 cases of miliary tuberculosis admitted to Hanyang University Hospital from Mar. 1989 to Dec.1992. The study investigated age and sex distribution, seasonal distribution, duration of symptoms before admission, pre-disposing factors, clinical symptoms, biochemical findings, chest X-ray findings, extrapulmonary tuberculosis associated with miliary tuberculosis, prognosis and mortality rate. Results: 1) The patients were most common in the age group between 20 and 29(23%) and the ratio of male to female was 1.4:1(male 23 : female 17). 2) Sputum smears for tubercle bacilli were positive in 5 cases(13%). 3) The most common clinical symptoms were fever with chilling(47.5%), coughing(47.5%), second most common symptom was dyspnea(32.5%), and the physical findings on admission were tachycardia(30%), weight loss(27.5%), meningeal signs(17.5%) in order. 4) The predisposing factors were heavy alcohol drinking(6 cases), steroid use(3 cases), pregnancy(2 cases) etc. 5) The chest X-ray findings on admission were miliary shadow only(40%), in addition pneumonic infiltration, pleurisy, and calcification in order. 6) The extrapulmonary tuberculosis associated with miliary tuberculosis were tuberculous meningitis(30%), bone and joint tuberculosis(17.5%), intestinal tuberculosis(15%) in order. 7) Biochemical findings were increased SGOT/SGPT(32.5%), increased alkaline phosphatase(32.5%), hypoalbuminemia(15%), hyponatremia(15%) etc. 8) About 4-6 weeks later after treatment(INH, RFP, PZA, EMB), 26 cases(65%) were improved on clinical symptoms or chest X-ray, 12 cases(30%) were stationary or aggravated, and 2 cases(5%) were died. Conclusion: For the early diagnosis and treatment of miliary tuberculosis, we must see its presentation and manifestation with greater interest and suspicion and investigate its predisposing factors and accompanying diseases.

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The Occurrence and Origin of a Syn-collisional Mélange in Timor (티모르섬 충돌 동시성 멜란지의 산상 및 기원)

  • Park, Seung-Ik;Koh, Hee Jae;Kim, Sung Won;Kihm, You Hong
    • Economic and Environmental Geology
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    • v.47 no.1
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    • pp.1-15
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    • 2014
  • The Bobonaro m$\acute{e}$lange is one of the youngest syn-collisional m$\acute{e}$langes, located between the Indo-Australian and Eurasian plates. The m$\acute{e}$lange has formed in association with a collision between the Australian continental margin and the Banda arc initiated in Neogene. The Suai area at the southern part of Timor is a good place to examine the genetic relationship between the m$\acute{e}$lange and other rock sequences because various tectonostratigraphic units coexist in the area. In this study, we present the structural characteristics and spatial distribution of the Bobonaro m$\acute{e}$lange investigated as a part of 1:25K scale geologic mapping in the area, and discuss on the origin of the m$\acute{e}$lange. The Bobonaro m$\acute{e}$lange in the Suai area is composed of unmetamorphosed clay matrix and blocks of various lithologies. The clay matrix mainly is reddish brown or greenish gray in colour, and has scaly texture. Most blocks are allochthonous, but mostly derived from nearby formations. Based on the internal structure and relationship with surrounding rocks, the Bobonaro m$\acute{e}$lange is genetically classified into 1) diapiric m$\acute{e}$lange; 2) tectonic m$\acute{e}$lange; and 3) broken formation. The spatial distribution of the Bobonaro m$\acute{e}$lange indicates that it intruded all pre-collisional units including the lower Australian continental margin unit(Gondwana megasequence) and the Banda arc unit. Taking the field evidences and previous genetic models into consideration, the Bobonaro m$\acute{e}$lange is interpreted to be mainly formed as a diapiric m$\acute{e}$lange originated from Gondwana megasequence, consistently effected by faulting events. This study reflects that diapiric m$\acute{e}$lange is a significant component in recent accretionay-collision belts. It suggests that diapiric process should be considered as a main genetic factor even in ancient m$\acute{e}$lange.

The Standard of Judgement on Plagiarism in Research Ethics and the Guideline of Global Journals for KODISA (KODISA 연구윤리의 표절 판단기준과 글로벌 학술지 가이드라인)

  • Hwang, Hee-Joong;Kim, Dong-Ho;Youn, Myoung-Kil;Lee, Jung-Wan;Lee, Jong-Ho
    • Journal of Distribution Science
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    • v.12 no.6
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    • pp.15-20
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    • 2014
  • Purpose - In general, researchers try to abide by the code of research ethics, but many of them are not fully aware of plagiarism, unintentionally committing the research misconduct when they write a research paper. This research aims to introduce researchers a clear and easy guideline at a conference, which helps researchers avoid accidental plagiarism by addressing the issue. This research is expected to contribute building a climate and encouraging creative research among scholars. Research design, data, methodology & Results - Plagiarism is considered a sort of research misconduct along with fabrication and falsification. It is defined as an improper usage of another author's ideas, language, process, or results without giving appropriate credit. Plagiarism has nothing to do with examining the truth or accessing value of research data, process, or results. Plagiarism is determined based on whether a research corresponds to widely-used research ethics, containing proper citations. Within academia, plagiarism goes beyond the legal boundary, encompassing any kind of intentional wrongful appropriation of a research, which was created by another researchers. In summary, the definition of plagiarism is to steal other people's creative idea, research model, hypotheses, methods, definition, variables, images, tables and graphs, and use them without reasonable attribution to their true sources. There are various types of plagiarism. Some people assort plagiarism into idea plagiarism, text plagiarism, mosaic plagiarism, and idea distortion. Others view that plagiarism includes uncredited usage of another person's work without appropriate citations, self-plagiarism (using a part of a researcher's own previous research without proper citations), duplicate publication (publishing a researcher's own previous work with a different title), unethical citation (using quoted parts of another person's research without proper citations as if the parts are being cited by the current author). When an author wants to cite a part that was previously drawn from another source the author is supposed to reveal that the part is re-cited. If it is hard to state all the sources the author is allowed to mention the original source only. Today, various disciplines are developing their own measures to address these plagiarism issues, especially duplicate publications, by requiring researchers to clearly reveal true sources when they refer to any other research. Conclusions - Research misconducts including plagiarism have broad and unclear boundaries which allow ambiguous definitions and diverse interpretations. It seems difficult for researchers to have clear understandings of ways to avoid plagiarism and how to cite other's works properly. However, if guidelines are developed to detect and avoid plagiarism considering characteristics of each discipline (For example, social science and natural sciences might be able to have different standards on plagiarism.) and shared among researchers they will likely have a consensus and understanding regarding the issue. Particularly, since duplicate publications has frequently appeared more than plagiarism, academic institutions will need to provide pre-warning and screening in evaluation processes in order to reduce mistakes of researchers and to prevent duplicate publications. What is critical for researchers is to clearly reveal the true sources based on the common citation rules and to only borrow necessary amounts of others' research.

Deformational Phased Structural Characteristics of the Hadong Southern Anorthosite Complex and its Surrounding Area in the Jirisan Province, Yeongnam Massif, Korea (영남육괴 지리산지구에서 하동 남부 회장암복합체와 그 주변지역의 변형단계별 구조적 특성)

  • Lee, Deok-Seon;Kang, Ji-Hoon
    • The Journal of the Petrological Society of Korea
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    • v.22 no.2
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    • pp.179-195
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    • 2013
  • The study area, which is located in the southeastern part of the Jirisan province, Yeongnam massif, Korea, is mainly composed of the Precambrian Hadong southern anorthosite complex (HSAC), the Jirisan metamorphic rock complex (JMRC) and Cretaceous sedimentary rock which unconformably covers them. Lithofacies distribution of the Precambrian constituent rocks mainly shows NS and partly NE trends. This paper researched deformational phased structural characteristics of HSAC and JMRC based on the geometric and kinematic features and the forming sequence of multi-deformed rock structures, and suggests that the geological structures of this area was formed through at least three phases of ductile deformation. The first phase ($D_1$) of deformation happened due to the large-scale top-to-the SE shearing, and formed the sheath or "A"-type fold and the regional tectonic frame of NE trend in the HSAC and JMRC. The second phase ($D_2$) of deformation, like the $D_1$ deformation, regionally occurred under the EW-directed tectonic compression, and most of the NE-trending $D_1$ tectonic frame was reoriented into NS trend by the active and passive folding, and the persistent and extensive ductile shear zone (Hadong shear zone) with no less than 2.3~1.4 km width was formed along the eastern boundary of HSAC and JMRC through the mylonitization process. The third phase ($D_3$) of deformation occurred under the NS-directed tectonic compression, and partially reoriented the pre-$D_3$ structural elements into ENE or WNW direction. It means that the distribution of Precambrian lithofacies showing NE trend locally and NS trend widely in this area is closely associated with the $D_1$ and $D_2$ deformations, respectively, and the NS-trending Hadong shear zone in the eastern part of Hadong northern anorthosite complex, which is located in the north of Deokcheon River, also extends into the HSAC with continuity.

Prediction of Potential Species Richness of Plants Adaptable to Climate Change in the Korean Peninsula (한반도 기후변화 적응 대상 식물 종풍부도 변화 예측 연구)

  • Shin, Man-Seok;Seo, Changwan;Lee, Myungwoo;Kim, Jin-Yong;Jeon, Ja-Young;Adhikari, Pradeep;Hong, Seung-Bum
    • Journal of Environmental Impact Assessment
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    • v.27 no.6
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    • pp.562-581
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    • 2018
  • This study was designed to predict the changes in species richness of plants under the climate change in South Korea. The target species were selected based on the Plants Adaptable to Climate Change in the Korean Peninsula. Altogether, 89 species including 23 native plants, 30 northern plants, and 36 southern plants. We used the Species Distribution Model to predict the potential habitat of individual species under the climate change. We applied ten single-model algorithms and the pre-evaluation weighted ensemble method. And then, species richness was derived from the results of individual species. Two representative concentration pathways (RCP 4.5 and RCP 8.5) were used to simulate the species richness of plants in 2050 and 2070. The current species richness was predicted to be high in the national parks located in the Baekdudaegan mountain range in Gangwon Province and islands of the South Sea. The future species richness was predicted to be lower in the national park and the Baekdudaegan mountain range in Gangwon Province and to be higher for southern coastal regions. The average value of the current species richness showed that the national park area was higher than the whole area of South Korea. However, predicted species richness were not the difference between the national park area and the whole area of South Korea. The difference between current and future species richness of plants could be the disappearance of a large number of native and northern plants from South Korea. The additional reason could be the expansion of potential habitat of southern plants under climate change. However, if species dispersal to a suitable habitat was not achieved, the species richness will be reduced drastically. The results were different depending on whether species were dispersed or not. This study will be useful for the conservation planning, establishment of the protected area, restoration of biological species and strategies for adaptation of climate change.

Analysis of Growth-Decline Type and Factors Influencing Growth Commercial Area Using Sales Data in Alley Commercial Area - Before and After COVID-19 - (골목상권 매출액 데이터를 활용한 성장-쇠퇴 유형화와 성장상권 영향요인 분석 - 코로나19 전후를 대상으로 -)

  • Jiwan Park;Leebom Jeon;Seungil Lee
    • Journal of the Korean Regional Science Association
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    • v.39 no.1
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    • pp.53-66
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    • 2023
  • Due to COVID-19, the external activities of urban residents have greatly shrunk, causing a lot of damage to the commercial district, such as a decrease in population and sales. The downturn in commercial districts means the collapse of the infrastructure of the national economy, and can have serious side effects on the local economy and individual lives. Therefore, it is necessary to look at the alley commercial area, which is closely related to the national local economy, and pay attention to the damage and stagnation of the alley commercial area where small business owners are concentrated. The purpose of this study is to classify alley commercial districts into growth commercial districts and decline commercial districts by using commercial sales time series data and DTW time series group analysis for the pre- and post-COVID-19 period. The main findings of the study are as follows. First, using the time series data on commercial sales before and after COVID-19, the alley commercial districts were divided into growth commercial districts and decline commercial districts, and it was confirmed that the distribution of growth commercial districts and decline commercial districts was regionally different. Therefore, it is necessary to actively manage commercial districts in areas where many declining commercial districts are distributed, and it is required to prepare policies for each region in consideration of the spatial distribution of declining commercial districts. Second, during the COVID-19 period, face-to-face essential industries, density of guest facilities, and population density negatively affected the sustainability of commercial districts, which is the opposite of previous studies. This is the result of empirically confirming the specificity of the COVID-19 period and the negative effects of the integrated economy, and can be used as basic data for effective commercial district management and policy preparation in the event of a national disaster in the future. Third, the characteristics of the background of the commercial district had a significant effect on the sustainability of the commercial district, and the negative effect of the attracting facilities inducing population concentration in the background area was found. This suggests that it is necessary to consider the characteristics of the background as well as the inside of the commercial district when establishing policies to revitalize the commercial district and support small business owners in a national disaster situation.