• Journal of Ecology and Environment
• /
• v.45 no.1
• /
• pp.40-53
• /
• 2021

The level of soil organic carbon (SOC) fluctuates in different types of forest stands: this variation can be attributed to differences in tree species, and the variables associated with soil, climate, and topographical features. The present review evaluates the level of SOC in different types of forest stands to determine the factors responsible for the observed variation. Mixed stands have the highest amount of SOC, while coniferous (both deciduous-coniferous and evergreen-coniferous) stands have greater SOC concentrations than deciduous (broadleaved) and evergreen (broadleaved) tree stands. There was a significant negative correlation between SOC and mean annual temperature (MAT) and sand composition, in all types of forest stands. In contrast, the silt fraction has a positive correlation with SOC, in all types of tree stands. Variation in SOC under different types of forest stands in different landscapes can be due to differences in MAT, and the sand and silt fraction of soil apart from the type of forests.

• Bulletin of the Korean Mathematical Society
• /
• v.59 no.4
• /
• pp.879-895
• /
• 2022

This paper establishes the Baum-Katz type theorem and the Marcinkiewicz-Zymund type strong law of large numbers for sequences of coordinatewise negatively associated and identically distributed random vectors {X, X_n, n ≥ 1} taking values in a Hilbert space H with general normalizing constants $b_n=n^{\alpha}{\tilde{L}}(n^{\alpha})$, where ${\tilde{L}}({\cdot})$ is the de Bruijn conjugate of a slowly varying function L(·). The main result extends and unifies many results in the literature. The sharpness of the result is illustrated by two examples.

• Journal of Plant Biology
• /
• v.32 no.2
• /
• pp.109-119
• /
• 1989

Adhatoda vasica Nees is a shrubby component of tropical and subtropical vegetation in Pakistan. t harbours relatively few unhealthy associated species in and around its thickets. Aqueous extracts, rain leachates, litter from shoots and soil underneath it invariably reduced germination, early growth, biomass, moisture and chlorophyll contents of Pennisetum americanum, Setaria italica, Zea mays, Brassica campestris and Triticum vulgare in different laboratory expreiments. chromatographic analysis revealed the presence of caffeic, ferulic, vanillic, p-coumaric, p-OH-benzoic, and tannic acids in aqueous extracts. The phytotoxicity was related to the test species used, part assayed and parameter measured. It is suggested that the preclusion of the associated species and the dominance of A. vasica is primarily due to allelopathy. Negative grazing also provides better chances for its establishment.

• Journal of Digestive Cancer Research
• /
• v.10 no.2
• /
• pp.49-55
• /
• 2022

Helicobacter pylori (H. pylori) infection is associated with gastroduodenal diseases such as gastritis, peptic ulcer diseases, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. Furthermore, various extragastroduodenal diseases have been suggested to be related with H. pylori infection. Although no single factor has been considered the cause of gastroesophageal reflux disease (GERD), a negative association was found between the prevalence of H. pylori and GERD severity. Additionally, the role of eradication therapy of H. pylori in reflux esophagitis is controversial, and a significant correlation was found between successful H. pylori eradication rate and reflux esophagitis development. H. pylori infection remains an inconclusive and important issue in GERD. Thus, more experimental studies are necessary to elucidate the potential mechanisms.

• Journal of Korea Artificial Intelligence Association
• /
• v.1 no.2
• /
• pp.7-13
• /
• 2023

In this paper, Depression is a mental disorder characterized by a lack of enthusiasm and feelings of sadness, which significantly impairs daily functioning. In 2018, there was an increase in book sales in the essay genre, particularly the popularity of "healing essays." This trend is seen as challenging the negative image and prejudices associated with depression. In 2021, a significant rise in the proportion of 20-year-old patients with depression is attributed to factors like job-related stress, interpersonal issues, and financial burdens. Additionally, there is a strong correlation between depression and suicidal thoughts, particularly among individuals who have experienced feelings of depression. Despite the increasing prevalence of depression among young adults, research in this area is lacking. To address this gap, statistical tools such as logistic regression and chi-squared tests are employed. The analysis reveals various independent variables associated with feelings of depression, shedding light on the relationships between these factors.

• Journal of applied mathematics & informatics
• /
• v.27 no.1_2
• /
• pp.441-452
• /
• 2009

In this paper, a fifth order numerical method is presented for solving singularly perturbed differential-difference equations with negative shift. In recent papers the term negative shift has been using for delay. Similar boundary value problems are associated with expected first exit time problem of the membrane, potential in models for neuron and in variational problems in control theory. In the numerical treatment for such type of boundary value problems, first we use Taylor approximation to tackle terms containing small shifts which converts it to a boundary value problem for singularly perturbed differential equation. The two point boundary value problem is transformed into general first order ordinary differential equation system. A discrete approximation of a fifth order compact difference scheme is presented for the first order system and is solved using the boundary conditions. Several numerical examples are solved and compared with exact solution. It is observed that present method approximates the exact solution very well.

• Journal of the Korean Mathematical Society
• /
• v.48 no.1
• /
• pp.117-132
• /
• 2011

By developing a linear algebra program involving many different structures associated to a three-graded H*-algebra, it is shown that if L is a Lie triple automorphism of an infinite-dimensional topologically simple associative H*-algebra A, then L is either an automorphism, an anti-automorphism, the negative of an automorphism or the negative of an anti-automorphism. If A is finite-dimensional, then there exists an automorphism, an anti-automorphism, the negative of an automorphism or the negative of an anti-automorphism F : A $\rightarrow$ A such that $\delta$:= F - L is a linear map from A onto its center sending commutators to zero. We also describe L in the case of having A zero annihilator.

• Journal of Korean Neurosurgical Society
• /
• v.47 no.2
• /
• pp.137-139
• /
• 2010

A subarachnoid hemorrhage (SAH) associated with negative finding on four-vessel angiography is seen in 5 to 30% of patients with intracranial SAH. A previously silent lesion in the spinal canal may be responsible for the angiographically negative finding for cause of intracranial SAH. We report a case of upper cervical (C1-2) intradural schwannoma presenting with acute intracranial SAH. Repeated cerebral angiographic studies were negative, but cervical magnetic resonance imaging study and tissue pathology revealed a intradural-extramedullary schwannoma in C1-2 level. This case illustrates the importance of a high index of clinical suspicion for spinal disease in angiographically negative intracranial SAH patients.

• Bulletin of the Society of Naval Architects of Korea
• /
• v.24 no.4
• /
• pp.1-8
• /
• 1987

In this paper negative drift forces are discussed, which act on a two-dimensional cylinder exposed to slightly modulated waves in water of finite depth. By combining matched asymptotic expansion method with multiple scale technique, it is clearly shown that the slowly-varying drift force can be negative under certain circumstances: i) Incident waves are irregular or slightly modulated. ii) The water depth is finite compared to the wave length of carrier waves. iii) The gap between the keel of the cylinder and ocean floor is narrow. Then the negative drift forces are caused by the unbalance of hydrostatic force associated with set down. Real fluid and wave breaking effects are not considered.

• Journal of Families and Better Life
• /
• v.20 no.6
• /
• pp.61-68
• /
• 2002

Relations of regulation, negative emotionality and problem behaviors to school adjustment were examined for 1,105 elementary school children from 558 2nd grade and 547 5th grade. Children reported their regulation and negative emotionality and teachers rated children's problem behaviors such as hyperactive and withdrawal behaviors and school adjustment including school life, grades, social competence with peers and teacher. Measures of problem behaviors were highly contributed to the prediction of children's school adjustment, especially hyperactive to school life and grades and withdrawal to social competence with peers and teacher. Behavioral regulation was associated with school adjustment including school life and social functioning with teacher and was able to modulate the influence of hyperactive. It was found that depression had both direct and indirect effects via withdrawal behavior on school adjustment.