• Journal of the Korea Society of Computer and Information
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• v.17 no.11
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• pp.189-196
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• 2012

This paper proposes Swap algorithm for solving Dynamic Economic Dispatch (DED) problem. The proposed algorithm initially balances total load demand $P_d$ with total generation ${\Sigma}P_i$ by deactivating a generator with the highest unit generation cost $C_i^{max}/P_i^{max}$. It then swaps generation level $P_i=P_i{\pm}{\Delta}$, (${\Delta}$=1.0, 0.1, 0.01, 0.001) for $P_i=P_i-{\Delta}$, $P_j=P_j+{\Delta}$ provided that $_{max}[F(P_i)-F(P_i-{\Delta})]$ > $_{min}[F(P_j+{\Delta})-F(P_j)]$, $i{\neq}j$. This new algorithm is applied and tested to the experimental data of Dynamic Economic Dispatch problem, demonstrating a considerable reduction in the prevalent heuristic algorithm's optimal generation cost and in the maximization of economic profit.

• Journal of the Korea Convergence Society
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• v.9 no.1
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• pp.85-93
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• 2018

The purpose of the study was to investigate the prevalence and risk factors of chronic obstructive pulmonary disease(COPD) among nonsmokers from the 6th Korea National Health and Nutrition Examination Survey(2013-2015). We used complex sample cross analysis and logistic regression analysis on 4, 911 non-smokers among the patients with chronic obstructive pulmonary disease over 40 years of age. In general characteristics, the prevalence of COPD is higher in the old(p<.001), men(p<.001), rural(p=.044), without spouses(p<.001), less educated(p<.001), agriculture(p<.001). Also, the non-smoker's COPD risk factor is age(p<.001), gender(p<.001), education(p=.022), occupation(p=.022), pulmonary tuberculosis(p<.001), asthma(p<.001). It is necessary to develop a respiratory rehabilitation and intervention program that can be applied in clinical practice based on nursing assessment considering the COPD prevalence and risk factors.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.4C
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• pp.451-457
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• 2006

A peer-to-peer(P2P) network is inherently vulnerable to malicious attacks from participating peers because of its open, flat, and autonomous nature. This paper addresses the problem of effectively defending from active attacks of malicious peers at bootstrapping phase and at online phase, respectively. We propose a secure membership handling protocol to protect the assignment of ID related things to a newly joining peer with the aid of a trusted entity in the network. The trusted entities are only consulted when new peers are joining and are otherwise uninvolved in the actions of the P2P networks. For the attacks in online phase, we present a novel message structure applied to each message transmitted on the P2P overlay. It facilitates the detection of message alteration, replay attack and a message with wrong information. Taken together, the proposed techniques deter malicious peers from cheating and encourage good peers to obey the protocol of the network. The techniques assume a basic P2P overlay network model, which is generic enough to encompass a large class of well-known P2P networks, either unstructured or not.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.7B
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• pp.728-733
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• 2009

An ubiquitous environment has features like peer-to-peer and nomadic environments. Such features can be represented by peer-to-peer systems and mobile ad-hoc networks. P2P systems and MANETs share similar features, appealing for implementing P2P systems in MANET environment. However, if a P2P system designed for wired networks was applied to mobile ad-hoc environment, its performance was not good enough. Subsequently, this paper proposes a P2P system to improve performance using cross-layer design and the goodness of a node as a peer by using routing metric and P2P metric to choose favorable peers to connect. It also utilizes proactive approach for distributing peer information. The simulation results showed that the proposed system produced better performance in query success rate, query response time and energy consumption by reducing the routing path length.

• Korean Journal of Logic
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• v.19 no.2
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• pp.145-184
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• 2016

Williamson(1994) proved incompatibility of Gab Theory and Tarski T-schema. But this does not means that Gab Theory could not involve intuition on truth that is expressed by T-schema. I will show that Gab Theory and mutual entailment of 'p' and 'it is true that p'(p⊨T

and T

⊨p) are compatible. It will draw that Gab Theory can involve minimal intuition on truth. After all what I want to reveal is logical space for Gab Theory through the compatibility of the mutual entailment and negation of the Principle of Bivalence. To prove the compatibility, I will present a consequent relation which should be accepted whenever we accept Gab Theory and demonstrate Gab Theory and the mutual entailment imply following two thesis; 1) not-T

and T are not equivalent. 2) p entails T

but not-T

does not entails not-p.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.897-900
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• 2008

Various sequences of pH change were applied in a batch bioreactor to investigate pH shock effects on geldanamycin production by Streptomyces hygroscopicus subsp. duamyceticus JCM4427. In the control culture where the pH was not controlled, the maximum geldanamycin concentration was 414 mg/l. With the pHS1 mode of pH shock, that is, an abrupt pH change from pH 6.5 to pH 5.0 and then being maintained at around pH 5.0 afterward, 768 mg/l of geldanamycin was produced. With pHS2, in which the pH was changed sequentially from pH 6.7 to pH 5.0 and then back to pH 6.0, 429 mg/l of geldanamycin was produced. With pHS3 having a sequential pH change from pH 6.0 to pH 4.0 and then back to pH 6.5 followed by the third pH shock to pH 5.5, no geldanamycin production was observed. Considering that the productivity with pHS1 was about two-fold of that of the control culture with no pH control, we concluded that a more sophisticated manipulation of pH would further promote geldanamycin production.

• Radiation Oncology Journal
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• v.16 no.1
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• pp.1-6
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• 1998

Purpose : To determine the incidence and prognostic effect of p53 expression in patients with advanced supralottic cancer. Materials : Twenty-one cases of total 48 advanced supraglottic cancer patients who received postoperative adjuvant radiation therapy were evaluated by immunohistochemical staining employing p53 monoclonal antibody. Result : Three out of six stage III patients and four out of fifteen stage IV patients showed p53 expression without statistically significant difference (p=0.608). Five year survival rates are $93\%$ in p53 negative, $80\%$ in p53 positive patients and there was no significant difference(p=0.776). p53 expression does not show statistically significant correlation with primary tumor status(p=0.877), lymph node status(p=0.874) and age(p=0.64). Conclusion : There was no statistically significant correlation between traditionally known risk factors and p53 expression.

• Korean Journal of Radiology
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• v.24 no.7
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• pp.668-680
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• 2023

Objective: To compare multiparametric magnetic resonance imaging (MRI) features of intraductal carcinoma of the prostate (IDC-P) with those of prostatic acinar adenocarcinoma (PAC) and develop prediction models to distinguish IDC-P from PAC and IDC-P with a high proportion (IDC ≥ 10%, hpIDC-P) from IDC-P with a low proportion (IDC < 10%, lpIDC-P) and PAC. Materials and Methods: One hundred and six patients with hpIDC-P, 105 with lpIDC-P and 168 with PAC, who underwent pretreatment multiparametric MRI between January 2015 and December 2020 were included in this study. Imaging parameters, including invasiveness and metastasis, were evaluated and compared between the PAC and IDC-P groups as well as between the hpIDC-P and lpIDC-P subgroups. Nomograms for distinguishing IDC-P from PAC, and hpIDC-P from lpIDC-P and PAC, were made using multivariable logistic regression analysis. The discrimination performance of the models was assessed using the receiver operating characteristic area under the curve (ROC-AUC) in the sample, where the models were derived from without an independent validation sample. Results: The tumor diameter was larger and invasive and metastatic features were more common in the IDC-P than in the PAC group (P < 0.001). The distribution of extraprostatic extension (EPE) and pelvic lymphadenopathy was even greater, and the apparent diffusion coefficient (ADC) ratio was lower in the hpIDC-P than in the lpIDC-P group (P < 0.05). The ROC-AUCs of the stepwise models based solely on imaging features for distinguishing IDC-P from PAC and hpIDC-P from lpIDC-P and PAC were 0.797 (95% confidence interval, 0.750-0.843) and 0.777 (0.727-0.827), respectively. Conclusion: IDC-P was more likely to be larger, more invasive, and more metastatic, with obviously restricted diffusion. EPE, pelvic lymphadenopathy, and a lower ADC ratio were more likely to occur in hpIDC-P, and were also the most useful variables in both nomograms for predicting IDC-P and hpIDC-P.

• Journal of the Korean Dietetic Association
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• v.30 no.1
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• pp.41-60
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• 2024

The number of elderly in care facilities is increasing in parallel with a rapid increase in the elderly population in Korea. We analyzed the meal satisfaction ratings, food preferences, and nutritional intakes of 74 patients aged ≥65 years living in a nursing hospital in Daegu. Food preferences were high for cooked rice, rice gruel, meat soup, soybean paste stew, beef, frozen pollack, squid, egg, spinach, sea mustard, cabbage kimchi, apple, peanut, drinking yogurt, pickled perilla leaves, and salted squid. Preferences for duck (P<0.01) and vegetable (P<0.01) cooking method were significantly different for men and women, and preference for soybean paste stew increased with age (P<0.05). Regarding nutrient intakes, men had higher energy (P<0.01), carbohydrates (P<0.05), and zinc (P<0.05) intakes than women, while women had higher vitamin C (P<0.05) intake than men. Furthermore, energy (P<0.001), carbohydrates (P<0.001), protein (P<0.05), dietary fiber (P<0.01), vitamin B₆ (P<0.01), phosphorus (P<0.05), and zinc (P<0.001) intakes significantly decreased with age. Men had a significantly higher nutrient adequacy ratios (NARs) for carbohydrates (P<0.05) and cal- cium (P<0.01) than women, while women had a significantly higher NARs for protein (P<0.05), vitamin A (P<0.01), vitamin C (P<0.05), thiamine (P<0.01), riboflavin (P<0.001), iron (P<0.001), and zinc (P<0.01). Mean adequacy ratios were 0.69 for men and 0.75 for women. In particular, NARs for carbohydrates (P<0.01), vitamin B₆ (P<0.01), and calcium (P<0.05) decreased significantly with age. In summary, the study shows that supplementing vitamin C, vitamin B₆, calcium, and iron, reducing sodium, and providing meals that reflect preferences will improve the nutritional statuses of elderly residents in a nursing hospital.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.3
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• pp.404-409
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• 2009

A total of 240 day-old broiler chicks were used to study the effects of phytase on performance and phosphorus (P) excretion from birds fed diets containing low phytate barleys formulated without inorganic P. A positive control based on Harrington barley (HB) was formulated to meet requirements for total P. Three experimental diets, based on either HB (0.39% total P with 0.28% phytate P) or the low phytate varieties LP 422 (0.36% total P with 0.14% phytate P) and LP 955 (0.40% total P with 0.01% phytate P), were formulated to be below requirements for total P by removing all the inorganic P from the diet. The four diets were fed with and without 1,000 FTU/kg phytase. Apparent P digestibility was significantly higher (p<0.01) for birds fed the low phytate barleys than for birds fed HB either supplemented or un-supplemented with inorganic P. P excretion was significantly lower (p<0.01) for birds fed HB without inorganic P than with inorganic P. P excretion was further reduced by the use of the low phytate barleys LP 422 and LP 455 (p<0.01). Phytase supplementation did not affect P excretion (p = 0.39). Body weight gain and feed intake were highest for birds fed the HB diet with inorganic P and lowest for birds fed the HB diet without inorganic P (p<0.01). Among the three low P diets, body weight gain and feed intake of broilers increased as the level of phytate in the barley declined (p<0.01). Phytase modestly increased body weight gain (p = 0.08) and feed intake (p = 0.04). The overall results of this study indicate that it may be possible to reduce the amount of inorganic P used when formulating diets with low phytate barley compared with the levels needed when formulating diets with normal phytate barley. However, it is not possible to completely replace the inorganic P in diets containing low phytate barley without impairing poultry performance. Feeding diets devoid of supplementary inorganic P in combination with low phytate barley resulted in a significant reduction in P excretion by poultry.