• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.3
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• pp.277-288
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• 2013

3GPP LTE-Advanced (Third Generation Partnership Project Long Term Evolution-Advanced) as a next generation mobile communication standard introduced small base stations such as femto cells or pico cells, and D2D (Device-to-Device) communications between mobiles in the proximity in order to satisfy the needs of rapidly growing wireless data traffic. A diverse range of topics has been studied to solve various interference situations which may occur within a single cell. In particular, an introduction of a small base station along with D2D communication raises important issues of how to increase the channel capacity and frequency efficiency in HetNets (Heterogeneous Networks). To this end, we propose in this paper methods to manage the interference between the macro cell and other small cells in the HetNet to improve the frequency efficiency. The proposed CCN (Cluster Coordinator Node)-assisted ICI (Inter-Cell Interference) avoidance methods exploit the CCN to control the interference in HetNet comprising of an MeNB (Macro enhanced Node-B) and a large number of small cells. A CCN which is located at the center of a number of small cells serves to avoid the interference between macro cell and small cells. We propose methods of resource allocation to avoid ICI for user equipments within the CCN coverage, and evaluate their performance through system-level computer simulations.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.13 no.1
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• pp.93-103
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• 2002

The aim of this study is to examine the diagnostic profiles and related clinical variables of children with attention and hyperactivity in psychiatric outpatient clinic. Seventy one children with age range of 5 to 14 were diagnosed by DSM-IV, and assessment battery including KEDI-WISC, KPI-C, ADS(ADHD Diagnostic System) were completed. The subjects were divided into 3 diagnostic groups：ADHD only(n=17), ADHD comorbid(n=27), Other diagnosis(n=27). The results were as follows：In ADHD comorbid group, tic disorder, developmental language disorder, borderline intellectual function, oppositional defiant/conduct disorder, and learning disorder were combined in descending order. Other diagnosis group consisted of tic disorder, borderline intellectual function, depression/anxiety, oppositional defiant/conduct disorder, and others. There were significant differences in IQ, PIQ, and VIQ among the three groups, and ADHD only group showed higher scores of IQ and VIQ than ADHD comorbid group. On the KPI-C, there were no significant differences in all subscales among the three groups. On the visual ADS, omission error and sensitivity showed significant differences among the three groups, and ADHD comorbid group represented higher omission error and lower sensitivity than other diagnostic group. The findings indicated that the inattention and hyperactivity symptoms could be diagnosed into diverse psychiatric disorders in child psychiatry, and ADHD children with comorbidity will show more problems in academic performance and school adjustment.

• Korean Journal of Construction Engineering and Management
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• v.1 no.3 s.3
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• pp.124-134
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• 2000

In construction projects, the design information, which should contain accurate product information in a systematic way, needs to be applicable through the life-cycle of projects. However, paper-based 2D drawings and relevant documents has difficulties in communicating and sharing the owner's and architect's intention and requirement effectively and building a corporate knowledge base through on-going projects due to Tack of interoperability between specific task or function-oriented software and handling massive information. Meanwhile, computer and information technologies are being developed so rapidly that the practitioners are even hard to adapt them into the industry efficiently. 3D modeling capabilities in CAD systems are enormously developed and enables users to associate 3D models with other relevant information. However, this still requires a great deal of efforts and costs to have all the design information represented in CAD system, and the sophisticated system is difficult to manage. This research focuses on the transition period from 2D-based design Information management to 3D-based, which means co-existence of 2D and 3D-based management. This research proposes a model of a compound system of 2D and 3D-based CAD system which presents the general design information using 3D model integrating with 2D CAD drawings for detailed design information. This research developed an integrated information management system for design and specification by associating 2D drawings and 3D models, where 2D drawings represents detailed design and parts that are hard to express in 3D objects. To do this, related management processes was analyzed to build an information model which in turn became the basis of the integrated information management system.

• Applied Biological Chemistry
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• v.9
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• pp.105-109
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• 1968

1. The optimum temperature of amylase activity produced by Bacillus subtilis var. M-181 was $50^{\circ}C$, and its activity was lost by heating to $70^{\circ}C$, 10 minutes without addition of salts. 2. Addition of sodium salts effects for heat resistance of the amylase affected differently by kinds of the salt. Among organic sodium salts monosodium glutamate, sodium acetate as sodium propionate affected on heat resistance of the amylase relatively better effects. 3. Addition of 10mg of sodium sulfate per ml of enzyme solution $({D_{30}}^{40^{\circ}}\;1250/ml)$, showed maximum affect on the neat resistance. 4. Coexistence of calcium acetate and sodium acetate, affected on the hear resistance, remarkably.

• Korean Journal of Ecology and Environment
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• v.41 no.3
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• pp.294-300
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• 2008

The stable isotopes ratios ($\delta^{13}C\;and\;\delta^{15}N$) of two coexisting species of zooplankton (Daphnia longispina and Acanthodiaptomus pacificus) and POM were determined in two alpine lakes in Japan. The difference of $\delta^{13}C$ between A. pacificus and D. longispina was 4.1$\pm$0.9‰ in Lake Shirakoma, which was larger than in Lake Panke. Whereas the difference of $\delta^{15}N$ between A. pacificus and D. longispina (2.6$\pm$0.8‰) was larger in Lake Panke than in Lake Shirakoma. $\delta^{13}C$ of POM (-26.6$\pm$1.2‰) in Lake Shirakoma was different from those of zooplankton; it was heavier than those of D. longispina and A. pacificus by 3.7$\pm$1.6‰ and 7.8$\pm$1.0‰, respectively. Whereas $\delta^{15}N$ of POM (2.0$\pm$0.8‰) was similar with those of both A. pacificus and D. longispina. This implies that the two lakes may have different trophic structure and food sources for zooplankton, and each species are grazing on selectively different components of POM. The temporal variation of $\delta^{13}C$ for each zooplankton species was associated with lipid contents of zooplankton in both lakes. The results showed that stable isotope composition of zooplankton can be an useful information for understanding energy pathways and trophic structures in lakes.

• The Journal of the Petrological Society of Korea
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• v.3 no.3
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• pp.185-195
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• 1994

An experimental study of iron-aluminium partitioning between synthetic garnet and synthetic epidote was carried out, as equilibrium was maintained in the exchange reaction expressed as follows : $Ca_3Fe_2Si_3O_12\+\2\Ca_2Al_2AlSi_3O_12$(0H) = $Ca_3Al_2Si_3O_12\+\Ca_2Al_2FeSi_3O_12$(0H) Temperature has a pronounced effect on the distribution of Fe and A1 between the minerals. However, the pressure effect is not so drastic as in the exchange reaction. With increasing temperature, $Fe^{+3}$ becomes redistributed from garnet into epidote, whereas A1 becomes redistributed from epidote into garnet. This is in line with the general principle of phase correspondence, as the temperature increases the more electropositive metal aluminium redistributes from epidote into garnet. The agreement between the experimental results of this study and the natural samples suggests that $K_D=X^{Ep}_{Fe}/X^{Gr}_{Fe}$ may be a useful geothermometer for metamorphic rocks containing garnet and epidote that are close to binary Fe-A1 compounds.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.237-240
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• 2000

본 연구에서는 한국 동해 대륙붕 해역에서의 주요 해양현상인 수직 수온구조의 단기변동, 수온전선, 그리고 내부파의 변동을 분석하고 이들 변화에 따른 음파의 음장변화를 고찰하였다. 한국 동해항 근해에서 수온의 수직적 변화는 계절적인 변화 이외에 약 2주간의 짧은 기간에도 매우 극적인 변화가 존재함이 실측자료를 통해 밝혀졌다. 1999년 관측된 CTD 자료를 바탕으로 음장 변화를 살펴본 결과 주파수 1kHz, 음원수심 $30{\cal}m$ 인 경우 수신기 수심에 따라 최소 3dB, 최대 10dB까지 차이를 가져올 수 있음을 알 수 있었다. 한국 동해에서 연안과 외해 사이에는 수온전선이 매우 자주 발달하며 여름에 가장 강한 것으로 알려져 있다. 동해항 근해에는 대표적인 수괴인 대마난류수와 북한한류수가 공존하며 이들의 상대적인 세력 변화 때문에 수은(음속)이 거리에 따라 급격하게 변하는 수온전선이 발달할 수 있다. 저주파수 대역 (200Hz)에 대한 간단한 시뮬레이션 결과는 수온전선이 정상적인 분포에 비해서 거리에 따라 7dB 정도의 큰 전파손실을 초래할 수 있음을 보인다. 한국 동해 연안에도 내부파가 존재한다는 사실이 최근 3년간의 연구 결과 밝혀졌다. 내부파는 외해에서 발생하여 대륙단을 거쳐 대륙붕으로 진행해 오면서 내부파 군 (Packets)으로 분산된다. 수직적 변화가 전체 수층의 $14\%$를 차지하는 간단한 형태의 내부파를 가정하여 음장변화를 시물레이션 한 결과 주파수 1 kHz, 음원수심 $20{\cal}m$인 경우 내부파는 수렴구역 형성을 현저하게 방해하여 최대 5dB까지의 차이를 유발하였다. 추후 이에 대한 연구는 내부파 전체의 시,공간적 분포 특성이 구체적으로 규명되면 보다 정확한 음장변화 추정이 이뤄져야 할 것으로 보인다. 또한 내부파와 음파의 상대적인 진행 방향에 따라 음장변화가 크게 다를 것이 예상되므로 이를 규명하기 위해서는 궁극적으로 3차원적인 음장분포 연구가 필요하다. 음향센서를 해저면에 매설할 경우 수충의 수온변화와 센서 주변의 수온변화 사이에는 어느 정도의 시간지연이 존재하게 되므로 이에 대한 영향을 규명하는 것도 센서의 성능예측을 위해서 필요하리라 사료된다.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.2
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• pp.147-154
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• 2019

Objectives : Cognitive dysfunction, including inattention, is often observed in patients with depression. Inattentive symptoms in patients with depression is similar to those among attention deficit/hyperactivity disorder (ADHD) patients. It is important to diagnose the two diseases accurately, because the treatment varies depending on the cause of inattention. This study aimed to investigate the coexistence rate of ADHD and the correlation between ADHD symptoms and depression in patients with depression. Methods : Participants in this study were 158 outpatients presenting with depression, who visited the psychiatric department from March 2015 to July 2018. Participants divided into a depression and a non-depression group according to the Korean version of the Center for Epidemiological Studies-Depression Scale (CES-D) score and were administered the following : a sociodemographic variables form (age, sex, academic background, occupation), the self-reporting test for adult ADHD (Adult Attention Deficit/Hyperactivity Disorder self-report scale-V 1.1; ASRS V1.1), and the Korean version of the Connors adult ADHD rating scale (K-CAARS). Descriptive statistical analysis, crossover analysis, t-tests, and Pearson's correlation coefficient were conducted on the data. Results : The coexistence rate of adult ADHD symptom was as high as 36.7% in patients with depression (p<0.001). In K-CAARS, the depression group (Inattention=1.80, Hyperactivity=1.92, Impulsivity=1.56, Self-concept=2.06) showed higher average scores on ADHD symptoms than the non-depressive group (Inattention=1.28, Hyperactivity=1.25, Impulsivity=1.09, Self-concept=1.42, p<0.001). Conclusions : This study confirmed that ADHD symptoms coexist in the depression group. When evaluating the symptoms of patients who complain of depression, it is suggested that they should be accurately diagnosed and appropriately treated with interest to the coexistence of ADHD symptoms and the possibility for ADHD diagnosis.

• Analytical Science and Technology
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• v.9 no.1
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• pp.35-42
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• 1996

A rapid analytical method based on capillary electrophoresis is described for the determination of trace anions in high-purity chemicals which is used to prevent corrosion demage in nuclear power plants. Separations are carried out at 20kV using trimethylsilane-coated fused-silica capillary ($70cm{\times}50$ or $75{\mu}m$ i.d.) with the electrolyte of 5mM Chromate(pH=8). Detection was achieved using on-column indirect photometry at 254nm. The simultaneous analysis of inorganic anions, chloride, nitrate, sulfate, azide and phosphate was performed using methods of hydrodynamic(>1ppm) and / or electrokinetic(<1ppm) injection. The results of studies on the coexisting anions on analyte ions shows that peak responses of analyte in hydrodynamic injection is constant without effect of coexisting anions, but those of analysis in electrokinetic injection is strongly dependant upon the kind of coexisting anions and its ionic mobility. The analyte enrichment rate, hence peak response, is positive relationship with the resistance of the sample solution. Thus, appropriate measures, such as standard addition or internal standard technique, must be used to account for differences in conductance of standard and sample solutions.

• The KIPS Transactions:PartD
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• v.10D no.3
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• pp.521-530
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• 2003

Various multimedia application services have been developed with techniques of high speed networks and computer. Among these services, a video-conference system over internet is useful and important, and its standardization has been shown in ITU-T H.323 and IETF SIP. H.323 standardization is currently used in many products, but two standardizations will coexist for a long time. Since the interoperability is needed between two standardizations, H.323-SIP gateway is developed for it. In audition, a video-conference system supporting two standardizations is necessary to be developed. We have implemented the video-conference terminal supporting both ITU-T H.323 and IETF SIP standardizations over internet. The system implementation has been designed using the common modules of two standardizations maximally, and the interoperability among different systems is satisfied through experiments.