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The disposal area of a deep geological repository (DGR) for the disposal of spent nuclear fuels (SNFs) is estimated considering the spacing between deposition holes and between disposal tunnels, as determined by a thermal analysis using the decay heat of a reference SNF. Given the relatively large amount of decay heat of the reference SNF, the disposal area of the DGR is found to be overestimated. Therefore, we develop a computer program using MATLAB, termed ACom (Assembly Combination), to combine SNFs when stored in canisters such that the decay heat per canister is evenly distributed. The stability of ACom was checked and the overall distribution of the decay heat per canister was analyzed. Finally, ACom was applied to disposal scenarios suggested in the conceptual design of a DGR for SNFs, and it was confirmed that the decay heat per canister could be evenly distributed and that the maximum decay heat of the canister could be much lower than that of a canister estimated using a reference SNF. ACom can be used to improve the disposal efficiency by reducing the disposal area of a DGR for SNFs by ensuringg a relatively even distribution of decay heat per canister.

A worldwide increase in tree decline and mortality has been linked to climate change and, where these represent foundation species, this can have important implications for ecosystem functions. This study tests a combined approach of phylogeographic analysis and species distribution modelling to provide a climate change context for an observed decline in crown health and an increase in mortality in Eucalyptus wandoo, an endemic tree of south-western Australia.Phylogeographic analyses were undertaken using restriction fragment length polymorphism analysis of chloroplast DNA in 26 populations across the species distribution. Parsimony analysis of haplotype relationships was conducted, a haplotype network was prepared, and haplotype and nucleotide diversity were calculated. Species distribution modelling was undertaken using Maxent models based on extant species occurrences and projected to climate models of the last glacial maximum (LGM).A structured pattern of diversity was identified, with the presence of two groups that followed a climatic gradient from mesic to semi-arid regions. Most populations were represented by a single haplotype, but many haplotypes were shared among populations, with some having widespread distributions. A putative refugial area with high haplotype diversity was identified at the centre of the species distribution. Species distribution modelling showed high climatic suitability at the LGM and high climatic stability in the central region where higher genetic diversity was found, and low suitability elsewhere, consistent with a pattern of range contraction.Combination of phylogeography and paleo-distribution modelling can provide an evolutionary context for climate-driven tree decline, as both can be used to cross-validate evidence for refugia and contraction under harsh climatic conditions. This approach identified a central refugial area in the test species E. wandoo, with more recent expansion into peripheral areas from where it had contracted at the LGM. This signature of contraction from lower rainfall areas is consistent with current observations of decline on the semi-arid margin of the range, and indicates low capacity to tolerate forecast climatic change. Identification of a paleo-historical context for current tree decline enables conservation interventions to focus on maintaining genetic diversity, which provides the evolutionary potential for adaptation to climate change.

Points out that sustainability as such does not provide a clearcut guide to policy. First one has to decide what is to be sustained. If this is agreed, it must be in an operational from. However, difficulties may still emerge since opinions may differ about how to achieve. This is illustrated by differences in the views of economists about how sustainable development is to be achieved. Orthodox economists stress the importance of the accumulation of man-made capital to achieve this end whereas neo-Malthusians stress the importance of conserving natural resource and environmental capital. Both take an anthropocentric point of view. For political reasons the neo-Malthusian has had little support but it may eventually turn out to be correct. Economics is concerned with reducing economic scarcity and economists have traditionally suggested four main ways of doing this of which economic growth is one. However, neo-Malthusian economists believe that this may not be a sustainable strategy – it may result in future poverty. It should be noted that economic systems are embedded in social and natural systems and depend on these. Economic sustainability depends on the sustainability of these other systems. So from this point of view, it is just one of several bottom lines. Values must be considered in relation to sustainability. Economics is completely anthropocentric in its approach. Therefore, economic approaches to conservation and sustainability can be at odds with the values of deep ecologists or those willing to accord rights to other sentient beings or ecosystems independent of human wishes, or those who want to make use of value judgments other than those based on the measuring rod of money. Consequently economics evaluation is sometimes ineffective in resolving social conflict, including conflict about what should be sustained. As a rule economics alone should not be the final arbiter of social decisions. It is a part (often an important part) of the social evaluation process but not the bottom line, or just one of many lines.

Research on digital twins (DTs) in the power system field has mainly focused on implementing DTs for specific resources, while few studies on electric vehicle (EV)-based DT implementation have considered integration and interoperability between systems. This study introduces a DT-based EV system operation framework to address the aforementioned research gap. The framework implements individual EVs, charging stations, and charging station operators (CPOs) as DTs, enabling integrated operation with the power grid. The DT-based EV agent supports independent decision-making on power service participation by considering location information, distance, charging amount, spare time, and incentives. In addition, the CPO can establish an optimal incentive strategy to induce EV users to participate in grid power services. The proposed DT systems map information between EVs, charging stations, and the grid, enabling analysis and verification of the impact of participants on charging station operation, grid stability, and economic efficiency in an independent environment. The effectiveness and usability of the proposed framework were verified through a case study on an incentive-based demand response program.

Dans les latitudes tempérées élevées, les ongulés donnent généralement naissance dans une fenêtre temporelle étroite lorsque les conditions sont optimales pour la survie de la progéniture au printemps ou au début de l'été, et utilisent une photopériode changeante pour les conceptions temporelles afin d'anticiper ces conditions. Cependant, dans les basses latitudes tropicales, la variation de la durée du jour est minime et la variation des précipitations rend le cycle saisonnier moins prévisible. Néanmoins, plusieurs espèces d'ongulés conservent des pics de naissance étroits dans de telles conditions, tandis que d'autres montrent que les naissances se propagent assez largement tout au long de l'année. Nous avons étudié comment la variation des précipitations d'une année à l'autre et d'une année à l'autre a influencé le moment de la reproduction de quatre espèces d'ongulés montrant ces modèles contrastés dans la région de Masai Mara au Kenya. Les quatre espèces présentaient des pics de naissance au cours de la période optimale putative au début de la saison humide. Pour le hartebeest et l'impala, le pic de naissance est diffus et la progéniture naît tout au long de l'année. En revanche, le topi et le phacochère ont montré une concentration saisonnière étroite de naissances, avec des conceptions supprimées une fois que les précipitations mensuelles sont tombées en dessous d'un seuil. Les fortes précipitations de la saison précédente et les fortes pluies précoces de l'année en cours ont amélioré la survie au stade juvénile de toutes les espèces, à l'exception de l'impala. Nos résultats révèlent comment la variation des précipitations affectant la croissance des graminées et donc la nutrition des herbivores peut régir la phénologie reproductive des ongulés dans les latitudes tropicales où la variation de la longueur du jour est minime. Le mécanisme sous-jacent semble être la suppression des conceptions une fois que les gains nutritionnels deviennent insuffisants. En réagissant de manière proximale à la variation des précipitations au cours de l'année, les ongulés de la savane tropicale sont moins susceptibles d'être affectés négativement par les conséquences du réchauffement climatique sur la phénologie de la végétation que les ongulés du Nord montrant un contrôle photopériodique plus rigide sur le moment de la reproduction. En latitudes templadas altas, los ungulados generalmente dan a luz dentro de una ventana de tiempo estrecha cuando las condiciones son óptimas para la supervivencia de la descendencia en primavera o principios del verano, y utilizan conceptos cambiantes de fotoperíodo a tiempo para anticipar estas condiciones. Sin embargo, en latitudes tropicales bajas, la variación de la duración del día es mínima, y la variación de las precipitaciones hace que el ciclo estacional sea menos predecible. Sin embargo, varias especies de ungulados conservan picos de nacimiento estrechos en tales condiciones, mientras que otras muestran nacimientos muy extendidos a lo largo del año. Investigamos cómo la variación interanual de las precipitaciones influyó en el tiempo reproductivo de cuatro especies de ungulados que muestran estos patrones contrastantes en la región de Masai Mara en Kenia. Las cuatro especies exhibieron picos de nacimiento durante el periodo óptimo putativo en la estación húmeda temprana. Para hartebeest e impala, el pico de nacimiento era difuso y las crías nacían durante todo el año. Por el contrario, topi y jabalí mostraron una estrecha concentración estacional de nacimientos, con concepciones suprimidas una vez que las precipitaciones mensuales cayeron por debajo de un nivel umbral. Las altas precipitaciones en la temporada anterior y las altas lluvias tempranas en el año en curso mejoraron la supervivencia en la etapa juvenil para todas las especies, excepto los impalas. Nuestros hallazgos revelan cómo la variación de la precipitación que afecta el crecimiento de la hierba y, por lo tanto, la nutrición de los herbívoros, puede gobernar la fenología reproductiva de los ungulados en latitudes tropicales donde la variación de la duración del día es mínima. El mecanismo subyacente parece ser la supresión de las concepciones una vez que las ganancias nutricionales se vuelven insuficientes. Al responder proximalmente a la variación de las precipitaciones dentro del año, es menos probable que los ungulados de la sabana tropical se vean afectados negativamente por las consecuencias del calentamiento global para la fenología de la vegetación que los ungulados del norte que muestran un control fotoperiódico más rígido sobre el tiempo reproductivo. In high temperate latitudes, ungulates generally give birth within a narrow time window when conditions are optimal for offspring survival in spring or early summer, and use changing photoperiod to time conceptions so as to anticipate these conditions. However, in low tropical latitudes day length variation is minimal, and rainfall variation makes the seasonal cycle less predictable. Nevertheless, several ungulate species retain narrow birth peaks under such conditions, while others show births spread quite widely through the year. We investigated how within-year and between-year variation in rainfall influenced the reproductive timing of four ungulate species showing these contrasting patterns in the Masai Mara region of Kenya. All four species exhibited birth peaks during the putative optimal period in the early wet season. For hartebeest and impala, the birth peak was diffuse and offspring were born throughout the year. In contrast, topi and warthog showed a narrow seasonal concentration of births, with conceptions suppressed once monthly rainfall fell below a threshold level. High rainfall in the previous season and high early rains in the current year enhanced survival into the juvenile stage for all the species except impala. Our findings reveal how rainfall variation affecting grass growth and hence herbivore nutrition can govern the reproductive phenology of ungulates in tropical latitudes where day length variation is minimal. The underlying mechanism seems to be the suppression of conceptions once nutritional gains become insufficient. Through responding proximally to within-year variation in rainfall, tropical savanna ungulates are less likely to be affected adversely by the consequences of global warming for vegetation phenology than northern ungulates showing more rigid photoperiodic control over reproductive timing. في خطوط العرض المعتدلة العالية، تلد ذوات الحوافر عمومًا في غضون فترة زمنية ضيقة عندما تكون الظروف مثالية لبقاء النسل في الربيع أو أوائل الصيف، وتستخدم تغيير الفترة الضوئية إلى مفاهيم زمنية لتوقع هذه الظروف. ومع ذلك، في خطوط العرض الاستوائية المنخفضة، يكون تباين طول اليوم ضئيلًا، ويجعل تباين هطول الأمطار الدورة الموسمية أقل قابلية للتنبؤ. ومع ذلك، فإن العديد من الأنواع ذوات الحوافر تحتفظ بقمم ولادة ضيقة في ظل هذه الظروف، في حين أن البعض الآخر يظهر أن الولادات تنتشر على نطاق واسع خلال العام. لقد حققنا في كيفية تأثير التباين في هطول الأمطار خلال العام وبين الأعوام على التوقيت التكاثري لأربعة أنواع من ذوات الحوافر تظهر هذه الأنماط المتناقضة في منطقة ماساي مارا في كينيا. أظهرت جميع الأنواع الأربعة قمم ولادة خلال الفترة المثلى المفترضة في موسم الأمطار المبكر. بالنسبة لحيوان النحل والامبالا، كانت ذروة الولادة منتشرة وولدت ذرية على مدار العام. على النقيض من ذلك، أظهر التوبي والخنزير الحربي تركيزًا موسميًا ضيقًا للولادات، مع قمع المفاهيم بمجرد انخفاض هطول الأمطار الشهري إلى ما دون مستوى العتبة. عزز ارتفاع هطول الأمطار في الموسم السابق وارتفاع الأمطار المبكرة في العام الحالي البقاء على قيد الحياة في مرحلة الشباب لجميع الأنواع باستثناء الإمبالا. تكشف النتائج التي توصلنا إليها كيف أن تباين هطول الأمطار الذي يؤثر على نمو العشب وبالتالي تغذية الحيوانات العاشبة يمكن أن يحكم الفينولوجيا الإنجابية لذوات الحوافر في خطوط العرض الاستوائية حيث يكون تباين طول اليوم ضئيلًا. يبدو أن الآلية الأساسية هي قمع المفاهيم بمجرد أن تصبح المكاسب الغذائية غير كافية. من خلال الاستجابة القريبة من التباين في هطول الأمطار خلال العام، فإن ذوات الحوافر في السافانا الاستوائية أقل عرضة للتأثر سلبًا بعواقب الاحترار العالمي على فينولوجيا الغطاء النباتي من ذوات الحوافر الشمالية التي تظهر تحكمًا دوريًا ضوئيًا أكثر صرامة في توقيت التكاثر.

Installations of an Energy Storage System (ESS) with various functions such as power stabilization of renewable energy, demand management, and frequency adjustment are increasing. In particular, ESS for demand management is being established for high-voltage customers (300 KVA–1000 KVA) who have placed an Auto Section Switch (ASS) at the connection point within the distribution system. However, a power outage may occur in the Power Receiving System (PRS) when a short-circuit fault due to insulation breakdown occurs at the ESS DC side. The reason for this breakdown is that the fault current is reduced by transformer impedance, and the ASS is opened before the DC power fuse. Therefore, using the Graphic Solution Method (GSM), this paper presents an operation algorithm for protection coordination that isolates the fault section by first operating the DC power fuse with a small fault current. Furthermore, fault analysis modeling for a PRS composed of a switchgear section, a main distribution panel, a Power Conditioning System (PCS), a power fuse, and a battery is performed through PSCAD/EMTDC. From the simulation results, it is confirmed that the fault section is quickly isolated, and power outages for high-voltage customers are prevented because the DC power fuse selected by the proposed operation algorithm of protection coordination is opened before the ASS.

Song Gupuh, a partially collapsed cave in the Gunung Sewu Limestones of East Java, Indonesia, contains over 16 m of deposits with a faunal sequence spanning some 70 ka. Major changes in the range of animals represented show the impact of climate change and humans. The Terminal Pleistocene and Early Holocene was a period of maximum biodiversity. Human use of Song Gupuh and other cave sites in the region also intensified significantly from ca. 12 ka, together with a new focus on exploitation of small-bodied species (macaque monkeys and molluscs), the first evidence for import of resources from the coast, and use of bone and shell tools. Human activity, especially after the onset of the Neolithic around 2.6 ka, subsequently contributed to a progressive loss of many species from the area, including tapir, elephant, Malayan bear, rhino and tiger, and this extinction process is continuing. We conclude by discussing the biogeographical significance of Song Gupuh in the context of other sites in Java (e.g. Punung, Wajak) and further afield (e.g. Liang Bua).