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A Study on Comparison of Changes in Ecological Characteristics for Bulgwangcheon(stream) Close-to Nature Section (불광천 자연형 하천 정비구간의 생태적 특성 변화 비교 연구)

  • Park, Won-Zei;Lee, Kyong-Jae;Han, Bong-Ho;Jang, Jae-Hoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.2
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    • pp.112-129
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    • 2012
  • The aim of this study was to provide basic data in managing the project that was carried out on Bulgwangcheon in a nature-friendly way to improve the conditions around the areas, which was brought to completion in 2002, based on changes in ecological characteristics. For this propose, this study examined documents related to the project, compared physical and enviromnental changes before and after the project was conducted and analyzed changes in the stream ecosystem. The result showed that in areas that effluent water was often observed, especially when it rained, the river wall was washed away and vegetation was found damaged. As for actual vegetation, this study compared planting coverage of each section of the research area and actual vegetation charts. The results indicated that Lespedeza spp., Aster koraiensis among mixed seeds that were planted in the reservoir path were almost swept away while Festuca arundinacea dominated the areas. Phragmites communis, Miscanthus sacchariflorns and Salix gracilistyla which had been planted in a small number were also almost washed out though a small number of them were left to form a colony. After examining the topography and structure of the plant community, this study found that areas where mixed seed were planted had changed into two types of vegetation: First type of area is dominated by P and R which are usually raised in apron with abundant floating particles. The second type of area is dominated by dry gramineous plant such as F and A. Areas around low flow channel where Phragmites communis, Miscanthus sacchariflorus and Salix gracilistyla planting construction method is applied was washed away with the width of low flow channel reduced. Though P, M and S formed a small community in some areas around the low flow area, they were in small number and in composition of simple plant species. Two ways were suggested in this study to manage the stream in an ecological way. First, adequate revetment construction methods should be applied by monitoring the flow of the stream as well as considering the flood control of urban streams. Second, target vegetation communities that are suitable for the environment of the stream should be chosen and be plantedconstantly with high density. At the same time, ornamental native plants shouldn't be planted as they have been and disturbing vegetation should be removed.

A Study on the Attraction Factors of Eco-city using Importance-Satisfaction Analysis - The Case of Suncheon City - (중요도-만족도(ISA) 분석을 활용한 생태도시 매력요인에 관한 연구 - 전남 순천시를 대상으로 -)

  • Lee, Jeong;Kim, Sa-Rang
    • Journal of the Korean Institute of Landscape Architecture
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    • v.42 no.2
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    • pp.52-64
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    • 2014
  • I the recent years, Seoul, Daejeon, Changwon, and Suncheon have started to strengthen P.R. efforts on eco-brands produced by the city and to publicize as a specialized tourist city in an attempt to change their identity and image. However, there is actually a question whether the efforts of the local governments have any direct impact on satisfaction with urban living environments and the attractions of the city. The purpose of this study was to examine the awareness of residents and visitors about the attractions of Suncheon City as an eco-city and to discuss the planning criteria for the eco-city brand building and its management. The research data was collected in Suncheon City and main results of this study are as follows. The residents and the visitors investigated were satisfied with the environmental friendliness of this city and regarded it as an eco-city. As a result of asking them why they viewed the city as an eco-city, many of the residents cited diverse green tracts of land as the reason, whereas the visitors replied they were satisfied with the state of marshy areas preserved by the city. The psychological factors related to the satisfaction of the eco-city by the residents were composed of four factors, 'cultural factor', 'urban infrastructure factor', 'ecological factor' and 'scenery factor'. The visitors were composed of five factors, 'cultural factor', 'urban infrastructure factor', 'ecological factor', 'scenery factor' and 'amenity factor'. Out of the factors, the cultural factor and the urban infrastructure factor were found to exert the largest influence on the overall satisfaction of the residents and the visitors. The ISA(Importance-Satisfaction Analysis) was made, the residents and the visitors gave top priority to 'diversity of natural attractions', 'pleasant season and weather', 'beautiful scenery', 'diversity of rare animals and plants', 'diversity of parks', 'green areas and streets', 'broad ecological area' and 'the preservation of marshy areas' among the attractions of the eco-city. They placed importance on the activation of green traffic and walking environments as well, but they weren't satisfied with the state of the two in the city. Therefore there was much room for improvement in that regard.

A STUDY ON FRACTURAL BEHAVIOR OF DENTIN-RESIN INTERFACE (상아질-복합레진 접착계면의 파괴거동에 대한 연구)

  • Ryu, Gil-Joo;Choi, Gi-Woon;Park, Sang-Jin;Choi, Kyung-Kyu
    • Restorative Dentistry and Endodontics
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    • v.32 no.3
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    • pp.208-221
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    • 2007
  • The fracture toughness test is believed as a clinically relevant method for assessing the fracture resistance of the dentinal restoratives. The objectives of this study were to measure the fracture toughness $(K_{1C})$ and microtensile bond strength of dentin-resin composite interface and compare their relationship for their use in evaluation of the integrity of the dentin-resin bond. A minimum of six short-rod specimens for fracture toughness test and fifteen specimens for microtensile bond strength test was fabricated for each group of materials used. After all specimens storing for 24 hours in distilled water at $37^{\circ}C$, they were tensile-loaded with an EZ tester universal testing machin. Statistical analysis was performed using ANOVA and Tukey's test at the 95% confidence level, Pearson's coefficient was used to verify the correlation between the mean of fracture toughness and microtensile bond strength. FE-SEM was employed on fractured surface to describe the crack propagation. Fracture toughness value of Clearfil SE Bond (SE) was the highest, followed by Adper Single Bond 2 (SB), OptiBond Solo (OB), ONE-STEP PLUS (0S), ScotchBond Multi-purpose (SM) and there was significant difference between SE and other 4 groups (p < 0.05). There were, however, no significant difference among SB, OB, OS, SM (p > 0.05). Microtensile bond strength of SE was the highest, followed by SB, OB, SM, OS and OS only showed significant lower value (p < 0.05). There was no correlation between fracture toughness and microtensile bond strength values. FE-SEM examination revealed that dentin bonding agent showed different film thickness and different failure pattern according to the film thickness. From the limited results of this study, it was noted that there was statistically no correlation between K1C and ${\mu}TBS$. We can conclude that for obtaining the reliability of bond strength test of dentin bonding agent, we must pay more attention to the test procedure and its profound scrutiny.

Comparison between REML and Bayesian via Gibbs Sampling Algorithm with a Mixed Animal Model to Estimate Genetic Parameters for Carcass Traits in Hanwoo(Korean Native Cattle) (한우의 도체형질 유전모수 추정을 위한 REML과 Bayesian via Gibbs Sampling 방법의 비교 연구)

  • Roh, S.H.;Kim, B.W.;Kim, H.S.;Min, H.S.;Yoon, H.B.;Lee, D.H.;Jeon, J.T.;Lee, J.G.
    • Journal of Animal Science and Technology
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    • v.46 no.5
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    • pp.719-728
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    • 2004
  • The aims of this study were to estimate genetic parameters for carcass traits on Hanwoo(Korean Native Cattle) and to compare two different statistical algorithms for estimating genetic parameters. Data obtained from 1526 steers at Hanwoo Improvement Center and Hanwoo Improvement Complex Area from 1996 to 2001 were used for the analyses. The carcass traits considered in these studies were carcass weight, dressing percent, eye muscle area, backfat thickness, and marbling score. Estimated genetic parameters using EM-REML algorithm were compared to those by Bayesian inference via Gibbs Sampling to find out statistical properties. The estimated heritabilities of carcass traits by REML method were 0.28, 0.25, 0.35, 0.39 and 0.51, respectively and those by Gibbs Sampling method were 0.29, 0.25, 0.40, 0.42 and 0.54, respectively. This estimates were not significantly different, even though the estimated heritabilities by Gibbs Sampling method were higher than ones by REML method. Since the estimated statistics by REML method and Gibbs Sampling method were not significantly different in this study, it is inferred that both mothods could be efficiently applied for the analysis of carcass traits of cattle. However, further studies are demanded to define an optimal statistical method for handling large scale performance data.

Lipoprotein(a) Level and Influential Factors in Children with Common Renal Diseases (소아에서 흔한 신장 질환에서 Lp(a)의 양상과 영향을 미치는 인자에 대한 평가)

  • O Chong-Gwon;Lim In-Seok
    • Childhood Kidney Diseases
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    • v.7 no.2
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    • pp.125-132
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    • 2003
  • Purpose : Lipoprotein(a) is a genetically determined risk factor for atherosclerotic vascular disease and is elevated in patients with renal disease. Especially the patients with nephrotic syndrome exhibit excessively high Lp(a) plasma concentrations. Also the patients with end-stage renal disease have elevated Lp(a) levels. But the mechanism underlying this elevation is unclear. Thus, in this study, by measuring the level of serum Lp(a) in common renal diseases in children, we hoped to see whether there would be a change in Lp(a) in renal diseases other than nephrotic syndrome. Then, we figured out its implications, and looked for the factors that affect the Lp(a) concentrations. Methods : A total of 75 patients(34 patients with hematuria of unknown etiology, 10 with hematuria and hypercalciuria, 8 with IgA nephropathy, 8 with poststreptococcal glomerulone phritis, 3 with $Henoch-Sch\"{o}nlein$ nephritis, 7 with urinary tract infection, and 5 with or- thostatic proteinuria) were studied. The control group included 20 patients without renal and liver disease. Serum Lp(a), total protein, and albumin levels, 24-hour urine protein and calcium excretions, creatinine clearance and the number of RBCs and WBCs in the urinary sediment were evaluated. Data analysis was peformed using the Student t-test and a P-value less than 0.05 was considered to be statistically significant. Results : LP(a) was not correlated with 24-hour urine calcium and creatinine. Lp(a) level had a positive correlation with proteinuria and negative correlation with serum albumin and serum protein. Among the common renal diseases in children, Lp(a) was elevated only in orthostatic proteinuria (P<0.05). Conclusion : Lp(a) is correlated with proteinuria, serum protein, and serum albumin, but not with any kind of specific renal disease. Afterward, Lp(a) needs to be assessed in patients with orthostatic proteinuria and its possible role as a prognostic factor could be confirmed.

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Effects of Ginsenosides and Their Metabolites on Voltage-dependent Ca2+ Channel Subtypes

  • Lee, Jun-Ho;Jeong, Sang Min;Kim, Jong-Hoon;Lee, Byung-Hwan;Yoon, In-Soo;Lee, Joon-Hee;Choi, Sun-Hye;Lee, Sang-Mok;Park, Yong-Sun;Lee, Jung-Ha;Kim, Sung Soo;Kim, Hyoung-Chun;Lee, Boo-Yong;Nah, Seung-Yeol
    • Molecules and Cells
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    • v.21 no.1
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    • pp.52-62
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    • 2006
  • In previous reports we demonstrated that ginsenosides, active ingredients of Panax ginseng, affect some subsets of voltage-dependent $Ca^{2+}$ channels in neuronal cells expressed in Xenopus laevis oocytes. However, the major component(s) of ginseng that affect cloned $Ca^{2+}$ channel subtypes such as ${\alpha}_{1C}$(L)-, ${\alpha}_{1B}$(N)-, ${\alpha}_{1A}$(P/Q)-, ${\alpha}_{1E}$(R)- and ${\alpha}_{1G}$(T) have not been identified. Here, we used the two-microelectrode voltage clamp technique to characterize the effects of ginsenosides and ginsenoside metabolites on $Ba^{2+}$ currents ($I_{Ba}$) in Xenopus oocytes expressing five different $Ca^{2+}$ channel subtypes. Exposure to ginseng total saponins (GTS) induced voltage-dependent, dose-dependent and reversible inhibition of the five channel subtypes, with particularly strong inhibition of the ${\alpha}_{1G}$-type. Of the various ginsenosides, $Rb_1$, Rc, Re, Rf, $Rg_1$, $Rg_3$, and $Rh_2$, ginsenoside $Rg_3$ also inhibited all five channel subtypes and ginsenoside $Rh_2$ had most effect on the ${\alpha}_{1C}$- and ${\alpha}_{1E}$-type $Ca^{2+}$ channels. Compound K (CK), a protopanaxadiol ginsenoside metabolite, strongly inhibited only the ${\alpha}_{1G}$-type of $Ca^{2+}$ channel, whereas M4, a protopanaxatriol ginsenoside metabolite, had almost no effect on any of the channels. $Rg_3$, $Rh_2$, and CK shifted the steady-state activation curves but not the inactivation curves in the depolarizing direction in the ${\alpha}_{1B}$- and ${\alpha}_{1A}$-types. These results reveal that $Rg_3$, $Rh_2$ and CK are the major inhibitors of $Ca^{2+}$ channels in Panax ginseng, and that they show some $Ca^{2+}$ channel selectivity.

Effect of reaction temperature on the particle size and crystal shape of precipitated calcium carbonate (반응온도가 침강성탄산칼슘의 입도 및 형상에 미치는 영향)

  • 송영준;박찬훈;조동성
    • Resources Recycling
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    • v.4 no.1
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    • pp.38-45
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    • 1995
  • The objective of this study was to investigate the effect of temperature on the formation of CaCO, polymorphs(i.e.,calcite, aragonite, vaterite) and on the crystal shape of CaCO,.The reaction systems were rnvestigated at the temperature range of 2.0%-85.3r, at the fixed cmditions ofconcentration and pressure, 2X10-' M, atomospheric pressure, respectively.The reaction systems studied include a Ca(HCO.,),-Air bubble, O Ca(OH)s-CO,, @ Ca(OH),-H,CO, ,Ca(OH1,-Na>CO,, O Ca(OH),-K,CO,, @ Ca(OH),-(NH,),CO,, D CaC1,-Na,CO,, CaC1,-K3C03, 8 CaC1,-(NH,,),CO,, 0 Ca(N0,X-Na,CO,, 03 Ca(N0,X-QCO,. 0 Ca(NO,),-(NH,XCO,. The results obtained are summarizedas follows:Calcite is formed at the temperature range of 2t-80"C and the highest calcite yield was obtained at 30%.Aragonite begins to be formed at the temperature range of 41.0%-53.0%. and the higher temperature is thehigher yield is obtained. pH of the reaction system affect the yield of aragonite, and the yield reaches the highestpercentage at the pH range of 10.0-11.0, and at the conditions of pH 12.3 or over, aragonite is scarcely formed.Vaterlle is fnrmed at the temperature range of 40.0% or less, and transites utterly to calcite within 10-60mmutes in the case of bemg residenced in mother liqmd which C1 is not contained, and within 140hours inthe case of containing CI-.s in the case of containing CI-.

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Effect of the Particle Size and Unburned Carbon Content on the Separation Efficiency of Fly ash in the Countercurrent Column Flotation (向流컬럼浮選機에서 石炭灰의 크기 및 未燃炭素 含量이 分離特性에 미치는 영향)

  • 이정은;이재근
    • Resources Recycling
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    • v.9 no.6
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    • pp.36-44
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    • 2000
  • Fly ash was composed of the unburned carbon and mineral particles. The former was able to attach on the bubbles, while the latter was not. Therefore, it was possible to separate the unburned carbon and the mineral from fly ash using the froth flotation process. This study was carried out to evaluate the separation efficiency as a function of the ny ash particle properties in the column flotation. Separation efficiency was analyzed for various size fraction of -38 fm,38~125 fm and 1125 W, and for various fly ash samples containing 7, 11, and 20 wt% unburned carbon. For the size fractions of -38 fm containing 7 wt% unburned carbon, separation efficiency was 86ft, whereas separation efficiency was found to be 74% for the size fraction of +125$\mu\textrm{m}$ containing 20 wt% unburned carbon. The results indicated that separation efficiency increased with the decrease in the particle size and the unburned carbon content of the fly ash.

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Earthquake impacts on hydrology: a case study from the Canterbury, New Zealand earthquakes of 2010 and 2011

  • Davie, Tim;Smith, Jeff;Scott, David;Ezzy, Tim;Cox, Simon;Rutter, Helen
    • Proceedings of the Korea Water Resources Association Conference
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    • 2011.05a
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    • pp.8-9
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    • 2011
  • On 4 September 2010 an earthquake of magnitude 7.1 on the Richter scale occurred on the Canterbury Plains in the South Island of New Zealand. The Canterbury Plains are an area of extensive groundwater and spring fed surface water systems. Since the September earthquake there have been several thousand aftershocks (Fig. 1), the largest being a 6.3 magnitude quake which occurred close to the centre of Christchurch on 22February 2011. This second quake caused extensive damage to the city of Christchurch including the deaths of 189 people. Both of these quakes had marked hydrological impacts. Water is a vital natural resource for Canterburywith groundwater being extracted for potable supply and both ground and surface water being used extensively for agricultural and horticultural irrigation.The groundwater is of very high quality so that the city of Christchurch (population approx. 400,000) supplies untreated artesian water to the majority of households and businesses. Both earthquakes caused immediate hydrological effects, the most dramatic of which was the liquefaction of sediments and the release of shallow groundwater containing a fine grey silt-sand material. The liquefaction that occurred fitted within the empirical relationship between distance from epicentre and magnitude of quake described by Montgomery et al. (2003). . It appears that liquefaction resulted in development of discontinuities in confining layers. In some cases these appear to have been maintained by artesian pressure and continuing flow, and the springs are continuing to flow even now. In spring-fed streams there was an increase in flow that lasted for several days and in some cases flows remained high for several months afterwards although this could be linked to a very wet winter prior to the September earthquake. Analysis of the slope of baseflow recession for a spring-fed stream before and after the September earthquake shows no change, indicating no substantial change in the aquifer structure that feeds this stream.A complicating factor for consideration of river flows was that in some places the liquefaction of shallow sediments led to lateral spreading of river banks. The lateral spread lessened the channel cross section so water levels rose although the flow might not have risen accordingly. Groundwater level peaks moved both up and down, depending on the location of wells. Groundwater level changes for the two earthquakes were strongly related to the proximity to the epicentre. The February 2011 earthquake resulted in significantly larger groundwater level changes in eastern Christchurch than occurred in September 2010. In a well of similar distance from both epicentres the two events resulted in a similar sized increase in water level but the slightly slower rate of increase and the markedly slower recession recorded in the February event suggests that the well may have been partially blocked by sediment flowing into the well at depth. The effects of the February earthquake were more localised and in the area to the west of Christchurch it was the earlier earthquake that had greater impact. Many of the recorded responses have been compromised, or complicated, by damage or clogging and further inspections will need to be carried out to allow a more definitive interpretation. Nevertheless, it is reasonable to provisionally conclude that there is no clear evidence of significant change in aquifer pressures or properties. The different response of groundwater to earthquakes across the Canterbury Plains is the subject of a new research project about to start that uses the information to improve groundwater characterisation for the region. Montgomery D.R., Greenberg H.M., Smith D.T. (2003) Stream flow response to the Nisqually earthquake. Earth & Planetary Science Letters 209 19-28.

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Freiheit vom Zwang und Freiheit von der Notwendigkeit: Eine Untersuchung des Begriffs der Freiheit des Willens bei Kant im Vergleich mit Leibniz (강제로부터의 자유와 필연으로부터의 자유: 라이프니츠와 칸트의 의지자유개념 비교연구)

  • Yun, Sunkoo
    • Journal of Korean Philosophical Society
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    • no.114
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    • pp.177-212
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    • 2016
  • Kants Begriff der Freiheit des Willens ist sehr kompliziert und verwirrend. Denn sowie es Ziel der ${\gg}$Kritik der praktischen Vernunft${\ll}$ ist, die reine praktische Vernunft zu beweisen, liegt der Fokus von Kants Begriff der Freiheit auf der Freiheit von Zwang, wobei Kant eine unbestimmte Haltung zur Freiheit von Notwendigkeit einnimmt und sie dann $schie{\ss}lich$ leugnet. Leibnizens Begriff der Freiheit dagegen hebt die Freiheit von Notwendigkeit hervor, denn er sagt, dass der menschliche Wille nicht nur vom Zwang der Leidenschaft, sondern auch von Notwendigkeit frei sei. Die Struktur von Leibnizens Freiheitslehre unterscheidet sich zwar sehr von der Kants, aber die Charakterlehren beider Denker, in denen die $M{\ddot{o}}glichkeit$ der Vereinbarkeit von Freiheit und Notwendigkeit behandelt werden, weisen viele Parallelen auf. Zudem ist Leibnizens Begriff der Freiheit sehr eindeutig. Daher ist ein Vergleich von Leibnizens und Kants Begriff der Freiheit nicht nur sinnvoll und $f{\ddot{u}}hrt$ zu einem besserem $Verst{\ddot{a}}ndnis$ von Kants Freiheitsbegriff, durch die vergleichende Analyse stellt sich zudem auch heraus, dass auch bei Kant nicht nur Freiheit von Zwang, sondern auch Freiheit von Notwendigkeit $m{\ddot{o}}glich$ ist. Leibniz geht $f{\ddot{u}}r$ seine Freiheitslehre von dem Begriff der Freiheit vom Zwang der Leidenschaft, welcher von allen Rationalisten anerkannt wird, sowie von dem Begriff der Freiheit von der Notwendigkeit, welcher von Spinoza negiert wird, aus. Kant dagegen definiert Freiheit als $Unabh{\ddot{a}}ngigkeit$ von den Naturgesetzen, was diesen Begriff von Anfang an unklar macht. Kant war sich anfangs der Zweideutigkeit dieses Konzepts nicht $bewu{\ss}t$ und hat es undeutlich gebraucht, doch in der Neuauflage von ${\gg}$Die Religion innerhalb der $blo{\ss}en$ Vernunft${\ll}$ erkennt er den Unterschied in den zwei Begriffen der Willensfreiheit, weshalb er bei der Rechtslehre in der ${\gg}$Metaphysik der Sitten${\ll}$ dazu kommt, die Wahlfreiheit zu negieren. Aber in den Abschnitten, wo Kant in der ${\gg}$Kritik der reinen Vernunft${\ll}$ und der ${\gg}$Kritik der praktischen Vernunft${\ll}$ die Vereinbarkeit von Freiheit und Notwendigkeit behandelt, $f{\ddot{u}}hrt$ Kant aus, so wie auch Leibniz, dass der intelligible Charakter des Menschen sich durch wiederholte freie Wahl formt, womit sich $best{\ddot{a}}tigt$, dass auch Kant die Freiheit der Wahl anerkannt hat. Kant leugnet die Wahlfreiheit, weil er der Ansicht ist, dass der Begriff der Freiheit als ein einheitlicher Begriff definiert werden muss. Doch Freiheit muss nicht zwingend einheitlich definiert werden. Da Freiheit von Zwang und Freiheit von Notwendigkeit nicht $widerspr{\ddot{u}}chliche$ Begriffe sind, $k{\ddot{o}}nnen$ sie dem selben Willen gleichzeitig zugeteilt werden. Auch wird erst hierdurch Autonomie $m{\ddot{o}}glich$ gemacht.