• Title/Summary/Keyword: stability period

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A Study of Policy Change on K-ETS and its Objective Conformity (한국 배출권거래제 정책 변동의 목적 부합성 연구)

  • Oh, Il-Young;Yoon, Young Chai
    • Journal of Climate Change Research
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    • v.9 no.4
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    • pp.325-342
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    • 2018
  • The Korea Emissions Trading Scheme ( K-ETS), which manages roughly 70% of the greenhouse gas emissions in South Korea, was initiated in 2015, after implementation of its 1st basic plan and the 1st allocation plan (2014) for the 1st phase (2015-2017). During the three and a half years since the launch of K-ETS, there have been critical policy change such as adjustment of the institutions involved, development and revision of the 2030 national GHG reduction roadmap, and change in the allocation plans. Moreover, lack of liquidity and fluctuation of carbon prices in the K-ETS market during this period has forced the Korean government to adjust the flexibility mechanism and auction permits of the market stability reserve. To evaluate the policy change in the K-ETS regarding conformance to its objectives, this study defines three objectives (Environmental Effectiveness, Cost Effectiveness and Economic Efficiency) and ten indicators. Evaluation of Environmental Effectiveness of K-ETS suggests that the national GHG reduction roadmap, coverage of GHG emitters and credibility of MRV positively affect GHG mitigation. However, there was a negative policy change implemented in 2017 that weakened the emission cap during the 1st phase. In terms of the Cost Effectiveness, the K-ETS policies related to market management and flexibility mechanism (e.g. banking, borrowing and offsets) were improved to deal with the liquidity shortage and permit price increase, which were caused by policy uncertainty and conservative behavior of firms during 2016-2018. Regarding Economic Efficiency, K-ETS expands benchmark?based allocation and began auction-based allocation; nevertheless, free allocation is being applied to sectors with high carbon leakage risk during the 2nd phase (2018-2020). As a result, it is worth evaluating the K-ETS policies that have been developed with respect to the three main objectives of ETS, considering the trial?and?error approach that has been followed since 2015. This study suggests that K-ETS policy should be modified to strengthen the emission cap, stabilize the market, expand auction-based allocation and build K-ETS specified funds during the 3rd phase (2021-2025).

A Causal Relationship between Family Social Capital and Self-Esteem using Autoregressive Cross-Lagged Modeling (가족 내 사회적 자본과 자아존중감과의 관계 -ARCL모델을 적용한 종단연구-)

  • Shin, Won-Young
    • Journal of the Korean Society of Child Welfare
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    • no.32
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    • pp.7-32
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    • 2010
  • The purpose of this research is to identify the longitudinal reciprocal relationship between family social capital and self-esteem of adolescents. Five waves of panel data from the Korea Youth Panel Survey were employed for this research. Korean Adolescents Policy Research Institute collected the first wave data in 2004 from elementary school children in 4th grade. Autoregressive cross-lagged modeling was performed to analysis the longitudinal reciprocal relationship between family social capital and self-esteem. The major findings were as follows. First, stability coefficient of family social capital and self-esteem showed that both variables were significantly stable over time. Secondly family social capital(t) had statistically significant effect on self-esteem(t+1), whereas self-esteem did not predict family social capital at a statistically significant level. These findings suggest that family social capital and self-esteem is stable overtime, and that obtaining family social capital and establishing positive self-esteem is important during this period in childhood. In addition, the results show that family social capital affects self-esteem, which highlights the importance of family social capital accumulation on the development of adolescent self-esteem.

Effect of a 12-week Shoulder Stability Rehabilitation Program on the Range of Motion and Muscle Strength of Baseball Players with Shoulder Instability (12주의 어깨 안정성 회복 프로그램이 견관절 불안정성 야구선수의 관절가동범위, 근력에 미치는 영향)

  • Yoon, Jin-Ho;Oh, Jae-Keun;Song, Ki-Jae
    • Journal of the Korea Convergence Society
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    • v.12 no.10
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    • pp.277-286
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    • 2021
  • This study investigated the effect of a 12-week rehabilitation program on the range of motion (ROM) and muscle strength of high school baseball players with shoulder instability. We allocated 12 players with shoulder instability to the rehabilitation group and 13 players without shoulder instability to the normal exercise group. Covariate analysis (ANCOVA) was performed to assess the ROM of the internal (IR) and external (ER) rotational joints before and after participating in the 12 weeks of rehabilitation, and two-way ANOVA was performed to assess isokinetic muscle strength. The statistical significance level was set at p<.05. The IR ROM of the dominant (D) shoulder with instability and non-dominant (ND) shoulder was significantly increased before and after the rehabilitation program. The total ROM of the D shoulder with instability significantly increased after rehabilitation. IR isokinetic strength significantly improved at an angular velocity of 180°/s after rehabilitation. These results indicate that the rehabilitation program used in this study could be effective in improving ROM and muscle strength in patients with shoulder instability. However, due to the limited results, additional research on the premise of extending the rehabilitation period is necessary.

GEO-KOMPSAT-2A AMI Best Detector Select Map Evaluation and Update (천리안위성2A호 기상탑재체 Best Detector Select 맵 평가 및 업데이트)

  • Jin, Kyoungwook;Lee, Sang-Cherl;Lee, Jung-Hyun
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.359-365
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    • 2021
  • GEO-KOMPSAT-2A (GK2A) AMI (Advanced Meteorological Imager) Best Detector Select (BDS) map is pre-determined and uploaded before the satellite launch. After the launch, there is some possibility of a detector performance change driven by an abrupt temperature variation and thus the status of BDS map needs to be evaluated and updated if necessary. To investigate performance of entire elements of the detectors, AMI BDS analyses were conducted based on a technical note provided from the AMI vendor (L3HARRIS). The concept of the BDS analysis is to investigate the stability of signals from detectors while they are staring at targets (deep space and internal calibration target). For this purpose, Long Time Series (LTS) and Output Voltage vs. Bias Voltage (V-V) methods are used. The LTS for 30 secs and the V-V for two secs are spanned respectively for looking at the targets to compute noise components of detectors. To get the necessary data sets, these activities were conducted during the In-Orbit Test (IOT) period since a normal operation of AMI is stopped and special mission plans are commanded. With collected data sets during the GK2A IOT, AMI BDS map was intensively examined. It was found that about 1% of entire detector elements, which were evaluated at the ground test, showed characteristic changes and those degraded elements are replaced by alternative best ones. The stripping effects on AMI raw images due to the BDS problem were clearly removed when the new BDS map was applied.

Faunal Composition and Spatial Distributions of Macrozoobenthos in the Tidal Flat of the Nakdong River Estuary, Korea (낙동강 하구 모래갯벌에 서식하는 대형저서동물의 군집구조와 분포양상)

  • Seo, Jin-Young;Choi, Jin-Woo;Shin, Kyoungsoon
    • Journal of Marine Life Science
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    • v.5 no.2
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    • pp.81-91
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    • 2020
  • This study was conducted to find the faunal composition and distribution patterns of macrobenthos where the sand tidal flat around barrier island at Nakdong River estuary in May, 2016 and 2017. The number of species ranged from 31 to 39, and density was from 789 to 1,644 ind.m-2 during the study period in the three tidal flats. The number of species and density were the highest in the tidal flat of Shinja-do and Jinwoo-do, respectively. The dominant species were Gammaridae unid. in amphipods of crustacea, Scoletoma heteropoda, Scoloplos armiger, Heteromastus filiformis, Prionospio japonica in polychaeta and Batillaria cumingii, Laternula marilina in mollusks from the three tidal flats. The proportion of carnivores such as crustacea and mollusks was higher in the upper part of the tidal flat, and polychaetes of deposit feeders, dominated in the middle and lower tidal flat. Overall, the intertidal macrobenthic communities in the study area showed a high proportion of carnivores. However, the sites where the mud content is high such as muddy sand sites, they showed a higher proportion of surface deposit feeders belonging to tube-builders which contribute to sediment stability. From this study, it seemed that the macrobenthic fauna of the sandy tidal flat at the Nakdong River estuary showed a similar fauna composition and zonal distribution patterns from those in other sandy tidal flats in Korea.

Quality Characteristics of Makgeolli during Freezing Storage (냉동저장에 따른 막걸리의 품질특성)

  • Lee, Jin-Won;Shim, Jae-Yong
    • Food Engineering Progress
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    • v.14 no.4
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    • pp.328-334
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    • 2010
  • Recently the enhancement and development of makgeolli processing to extend shelf life are constantly accomplished. However, the standardization to restrict microorganisms including cold chain system and sterilizing system has not been established yet. Therefore, the objective of this study was to investigate the storage stability of makgeolli using quick freezing (QF) and slow freezing (SF) storage methods. The storage period was 40 days. Every 10 days, the samples were taken from the quick and slow freezing storage chamber. And then the samples were put into a $10^{\circ}C$ refrigerator for 24 hr to thaw them. The final samples were evaluated for chemical experiments and microbial cell counts. As a result, reducing sugar content was dramatically increased after 10 days for all of the samples. In titratable acidity and color values case, these values did not significantly change by storage time. In case of lactic acid bacteria and yeasts for all the samples, there was a decreasing tendency with storage time. Especially, in case of lactic acid bacteria, the changes from the beginning microbial cell counts ($4.1{\times}10^7$ CFU/mL) for QF and SF after 20 days were $3.6{\times}10^6$ CFU/mL and $1.8{\times}10^4$ CFU/mL, respectively. This result showed that the freezing methods could restrict the microbial growth in makgeolli.

Disaster risk predicted by the Topographic Position and Landforms Analysis of Mountainous Watersheds (산지유역의 지형위치 및 지형분석을 통한 재해 위험도 예측)

  • Oh, Chae-Yeon;Jun, Kye-Won
    • Journal of Korean Society of Disaster and Security
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    • v.11 no.2
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    • pp.1-8
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    • 2018
  • Extreme climate phenomena are occurring around the world caused by global climate change. The heavy rains exceeds the previous record of highest rainfall. In particular, as flash floods generate heavy rainfall on the mountains over a relatively a short period of time, the likelihood of landslides increases. Gangwon region is especially suffered by landslide damages, because the most of the part is mountainous, steep, and having shallow soil. Therefore, in this study, is to predict the risk of disasters by applying topographic classification techniques and landslide risk prediction techniques to mountain watersheds. Classify the hazardous area by calculating the topographic position index (TPI) as a topographic classification technique. The SINMAP method, one of the earth rock predictors, was used to predict possible areas of a landslide. Using the SINMAP method, we predicted the area where the mountainous disaster can occur. As a result, the topographic classification technique classified more than 63% of the total watershed into open slope and upper slope. In the SINMAP analysis, about 58% of the total watershed was analyzed as a hazard area. Due to recent developments, measures to reduce mountain disasters are urgently needed. Stability measures should be established for hazard zone.

Comparative Efficacy of Synthetic and Natural Tenderizers on Quality Characteristics of Restructured Spent Hen Meat Slices (RSHS)

  • Kantale, Rushikesh Ambadasrao;Kumar, Pavan;Mehta, Nitin;Chatli, Manish Kumar;Malav, Om Prakash;Kaur, Amanpreet;Wagh, Rajesh Vishwanath
    • Food Science of Animal Resources
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    • v.39 no.1
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    • pp.121-138
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    • 2019
  • In the present study, comparative efficacy of natural as well as synthetic tenderizers on the quality characteristics of restructured spent hen meat slices (RSHS) was studied. Four different batches of RSHS viz. Control (without any tenderizer), T1 (1.25% calcium chloride replacing salt in formulation), T2 and T3 (1.5% each of pineapple rind and fig powder, replacing binder in the formulation) were developed in pre-standardized formulation. Vacuum tumbling was performed for 2.5 h and cooked product (RSHS) was assayed for quality attributes. Samples were packaged in aerobic conditions, stored for 21 days under refrigeration ($4{\pm}1^{\circ}C$) and were evaluated for pH, oxidative and microbial quality parameters at regular interval of 7 days. Water holding capacity of T2 was recorded the highest and significantly higher (p<0.05) than all other samples. The textural attributes of T2 were comparable to T1 but significantly higher (p<0.05) than C and T3. The colour attributes ($L^*$, $a^*$, and $b^*$ value) of T2 and T3 were improved due to use of natural tenderizers. During sensory evaluation, tenderness scores for T2 samples were recorded the highest. Throughout storage period, thiobarbituric acid reactive substances (TBARS), free fatty acids (FFA) and peroxide value (PV) followed an increasing trend for control as well as treated products; however, T2 showed a significantly (p<0.05) lower value than control and other treated samples. It can be concluded that good quality RSHS with better storage stability could be prepared by utilizing 1.5% pineapple rind powder as natural tenderizer.

Correction of Spondylolisthesis by Lateral Lumbar Interbody Fusion Compared with Transforaminal Lumbar Interbody Fusion at L4-5

  • Ko, Myeong Jin;Park, Seung Won;Kim, Young Baeg
    • Journal of Korean Neurosurgical Society
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    • v.62 no.4
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    • pp.422-431
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    • 2019
  • Objective : In an aging society, the number of patients with symptomatic degenerative spondylolisthesis (DS) is increasing and there is an emerging need for fusion surgery. However, few studies have compared transforaminal lumbar interbody fusion (TLIF) and lateral lumbar interbody fusion (LLIF) for the treatment of patients with DS. The purpose of this study was to investigate the clinical and radiological outcomes between TLIF and LLIF in DS. Methods : We enrolled patients with symptomatic DS at L4-5 who underwent TLIF with open pedicle screw fixation (TLIF group, n=41) or minimally invasive LLIF with percutaneous pedicle screw fixation (LLIF group, n=39) and were followed-up for more than one year. Clinical (visual analog scale and Oswestry disability index) and radiological outcomes (spondylolisthesis rate, segmental sagittal angle [SSA], mean disc height [MDH], intervertebral foramen height [FH], cage subsidence, and fusion rate) were assessed. And we assessed the changes in radiological parameters between the postoperative and the last follow-up periods. Results : Preoperative radiological parameters were not significantly different between the two groups. LLIF was significantly superior to TLIF in immediate postoperative radiological results, including reduction of spondylolisthesis rate (3.8% and 7.2%), increase in MDH (13.9 mm and 10.3 mm) and FH (21.9 mm and 19.4 mm), and correction of SSA ($18.9^{\circ}$ and $15.6^{\circ}$) (p<0.01), and the changes were more stable from the postoperative period to the last follow-up (p<0.01). Cage subsidence was observed significantly less in LLIF (n=6) than TLIF (n=21). Fusion rate was not different between the two groups. The clinical outcomes did not differ significantly at any time point between the two groups. Complications were not statistically significant. However, TLIF showed chronic mechanical problems with screw loosening in four patients and LLIF showed temporary symptoms associated with the surgical approach, such as psoas and ileus muscle symptoms in three and two cases, respectively. Conclusion : LLIF was more effective than TLIF for spondylolisthesis reduction, likely due to the higher profile cage and ligamentotactic effect. In addition, LLIF showed mechanical stability of the reduction level by using a cage with a larger footprint. Therefore, LLIF should be considered a surgical option before TLIF for patients with unstable DS.

A Study on the Stability of Using Alkali Solution Desalination on Gilt Plated Silver-Iron Artifacts (알칼리 수용액을 이용한 출토 철지금은장관정의 탈염처리 적용성 평가)

  • Park, Jun Hyeon;Bae, Go Woon;Chung, Kwang Yong
    • Journal of Conservation Science
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    • v.37 no.2
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    • pp.179-189
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    • 2021
  • In this study, the research objects are gilt plated silver-iron nails excavated from the west of the tombs in Neungsan-ri, Buyeo. A gilt plated silver-iron nail was fabricated by combining silver and iron via heating and then gilding amalgam on top of this combination, demonstrating that this ancient artifact that can be replicated using current technology. Since the metal (Au, Ag) surface of these gilt plated artifacts are covered with iron oxide, which slips into the cracks and scratches of the artifacts as well, desalination is essential. Based on the results of the preliminary experiment, the research objects were classified into grades A, B, and C, according to the degree of corrosion and then desalinated using an alkali solution (NaOH, Sodium Sesquicarbonate of 0.1 M) at 60℃. The results demonstrate that the more serious is the degree of corrosion, the more is the amount of Cl- detected. Further, more Cl- was released when NaOH was used than when sodium sesquicarbonate was used, for all grades except Grade A. Furthermore, the more serious is the degree of corrosion, the longer is the desalination period and the reaction with NaOH for all grades except Grade A. A comparison of the Fe composition of the surface before and after desalination shows that Fe composition is the use of NaOH resulted in a smaller increase compared with the use of sodium sesquicarbonate, for all grades except Grade B. However, four of the nails were damaged owing to NaOH (Grade B 3ea, Grade C 1ea) during desalination. Thus, Cl- ions are more stably released when sodium sesquicarbonate is used than when NaOH is used.