본 연구는 중국 허베이성 소재 정정고성(正定古城)을 사례로 경관문맥 보전 및 형성을 위한 지표 도출 을 목적으로 수행되었다. 이를 위해 문헌 및 관찰조사, 전문가를 대상으로 한 Delphi법과 AHP법 그리고 탐방객을 대상으로 한 IPA법에 의해 고성의 경관문맥 보전 및 형성전략을 주도할 지표를 추출하였다. 문화경관 보전이라는 핵심쟁점에 대해 경관문맥의 관점에서 종합하고 평가하여 문화경관의 보전전략 과 발전방향을 모색한 결과 시간 차원의 ‘중층성(重層性)’과 공간 차원의 ‘융합성(融合性)’이라는 2개 상위지표가 경관문맥의 의미와 기본 속성에 최적화된 개념으로 부상되었으며, 각각의 가중치는 0.620 과 0.379로 드러났다. 중요도와 만족도 구분없이 경관의 심미성과 시대적 연속성은 정정고성의 경관문 맥을 주도하는 중요지표로 부상되었으며, AHP가중치와 IPA중요도치의 통합분석 결과 경관 풍격의 연 속성과 경관 독특성의 하위지표는 정정고성의 장소정체성 요인으로 전문가와 탐방객에게 인식되고 있었다. 특히 ‘고성 정신과의 일관성’ 지표야말로 고성경관의 현상유지는 물론 전승해야 할 최고의 정 신문화임이 밝혀졌다.
This study aimed to build on past findings about differences in personal walking experiences by demonstrating what elements were beneficial to participants with different walking habits. Accordingly, this study established the relationships between valued walking elements and people’s motivation to walk, by dividing participants into three groups: Group W for people with a walking habit, Group HW for people who walk occasionally but not regularly, and Group NW for people who do not walk habitually. Participants walked a familiar and an unfamiliar route with a wearable device that recorded their heart-rate variability and electrodermal activity. Changes in the biometric data helped to identify the defining moments in each participant’s walk. Participants discussed these moments in one-on-one interviews with a researcher to pinpoint their valued walking elements. As a result, this study classified walking elements into six themes: “Surroundings,” “Social,” “Exploration,” “Route Plan,” “Physical Exercise,” and “Mental Thinking.” A walking habit development model was made to show how “Route Plan” and “Exploration” were beneficial to Group NW, “Social” and “Surroundings” were beneficial to Group HW, and “Route Plan,” “Mental Thinking,” and “Physical Exercise” were beneficial to Group W.
The simultaneous use of KOH and nitrogen to manufacture carbon materials provides these materials with properties that the presence of only one of these additives would not give them, such as high porosity and reactivity. However, it is difficult to obtain nitrogen-doped carbon materials with both high porosity and high nitrogen content, as the KOH significantly reduces the nitrogen content. In this review the complex relationships between nitrogen content and nitrogen precursor amount, KOH amount and the activation temperature are discussed, with a focus on the different N-functional groups and the porosity of the fabricated carbons. Generally, increasing activation temperature and increasing KOH amount decrease the nitrogen content due to reactions with the N-containing substructures of carbon, resulting in the release of nitrogen as N2, HCN and other N gases. Increasing these parameters can also result in the reduction of pyridine-N while the amount of quaternary-N increases simultaneously. Besides this, an increase in the amount of nitrogen precursor leads to an increase in the porosity of N-doped materials. However, too high amounts of the nitrogen precursor generate an excess of nitrogen which blocks the pore system and consequently reduces the porosity of the doped carbons.
Clogging of the filter media which is brought by physical, chemical, and biological factors tend to reduce the lifespan of filters and remains a challenge. In this study, a laboratory column test method was used to investigate the evolution of physical and biological clogging in a non-vegetated filter media system with layers of sand, gravel, and woodchip. Blank column tests using either sand or gravel were conducted and investigated. Several column setups with varying arrangements and particle sizes of sand and gravel were also prepared to identify the best filter media combination that is least susceptible to clogging without compromising the treatment capacity. Artificial stormwater runoff was introduced in the system at a specific hydraulic loading rate (HLR) and influent characteristics. The degree of clogging was quantified by monitoring the variations in the hydraulic head at different levels of the columns. Water samples were also collected, tested, and analyzed at the end of each test run in order to measure the treatment efficiency of the filter. The insights and results of this study can justify the physical and biological clogging formation in filter media and therefore be used to suggest some filter media particle size modifications that can help to improve the sediment removal and treatment performance. Moreover, it can also aid to reduce the maintenance frequency and costs of a stormwater filter system.
A comprehensive fractionation technique was applied to a set of water samples obtained along drinking water treatment process with ozonation and biological activated carbon (BAC) process to obtain detailed profiles of dissolved organic matter (DOM) and to evaluate the haloacetic acid (HAA) formation potentials of these DOM fractions. The results indicated that coagulation-sedimentation-sand filtration treatment showed limited ability to remove hydrophilic fraction (28%), while removal of hydrophobic and transphilic fraction were 57% and 40%, respectively. And ozonation and BAC treatment showed limited ability to remove hydrophobic fractions (6%), while removal of hydrophilic and transphilic fractions were 25% and 18%. The haloacetic acid formation potential (HAAFP)/dissolved organic carbon (DOC) of hydrophilic fraction was the highest along the treatment train and HAAFP/DOC of hydrophilic fraction was higher than hydrophobic and transphilic fraction as 23% 30%, because of better removal for hydrophobic fraction both in concentration and reactivity.
While a range of natural organic matter (NOM) types can generate high levels of disinfection by-products (DBPs) after chlorination, there is little understanding of which specific compounds act as precursors. Use of eight model compounds allows linking of explicit properties to treatability and DBP formation potential (DBPFP). The removal of model compounds by various treatment processes and their haloacetic acid formation potential (HAAFP) before and after treatment were recorded. The model compounds comprised a range of hydrophobic (HPO) and hydrophilic (HPI) neutral and anionic compounds. On the treatment processes, an ozone oxidation process was moderate for control of model compounds, while the HPO-neutral compound was most treatable with activated carbon process. Biodegradation was successful in removing amino acids, while coagulation and ion exchange process had little effect on neutral molecules. Although compared with the HPO compounds the HPI compounds had low HAAFP the ozone oxidation and biodegradation were capable of increasing their HAAFP. In situations where neutral or HPI molecules have high DBPFP additional treatments may be required to remove recalcitrant NOM and control DBPs.
쇄설성 퇴적층 위주의 퇴적상을 갖는 것으로 알려진 영일 지역 장기층군의 함탄층 내에 실제로는 상당한 규모의 화산쇄설성 퇴적암류가 혼재된다. 전체적으로 이 함탄층은 화성쇄설성 암상과 단순 쇄설성 암상이 교호되는 양상을 보인다. 부석편을 함유하는 응회암과 응회질 사암이 함탄층의 특징적인 화산쇄설성 암상을 이룬다. 상 하부 함탄층의 화산쇄설성 암석에서 속성기원으로 산출되는 변질광물로는 몬모릴로나이트와 클리놉틸로라이트가 주된 광물상을 이루고 여기에 단백석과 석영이 수반된다. 광물조성과 양이온 치환능력 면에서 일부 층준에서는 응회질 암석들이 저품 위 제올라이트나 벤토나이트 광층을 이룬다. 또한 대부분 1 m 미만의 박층을 이루기 때문에 전형적인 제올라이트나 벤토나이트 자원으로서의 유용성과 잠재성은 낮은 것으로 판단된다. 그렇지만 인접하는 이들 광층들이 함께 개발될 수 있다면, 광물조성과 CEC 수치 면에서 산성백토와 같은 흡착기능성 광물자원으로서의 활용 가능성은 충분한 것으로 평가된다.