• Title/Summary/Keyword: F4

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Effect of Whole Powder and Extracts of Gastrodiae Rhizoma on Serum Lipids and Body Fat in Rats Fed High-Fat Diet (천마 분말, 에탄올 및 열수추출물이 고지방식이를 급여한 흰쥐의 혈청지질과 체지방에 미치는 영향)

  • Kim, Kyung-Im;Han, Chan-Kyu;Seong, Ki-Seung;Lee, Ok-Hwan;Park, Jung-Min;Lee, Boo-Yong
    • Korean Journal of Food Science and Technology
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    • v.35 no.4
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    • pp.720-725
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    • 2003
  • Effects of Gastrodiae Rhizoma on serum lipids and body fat in rats fed high-fat diet supplemented with 10% (w/w) lard during 11-week experimental period were investigated. Ninety-six male rats were randomly divided into eight groups: A, negative control (lard 10%); B, positive control (lard 10%+rat chow+5 brix water extract); C, lard 10%+1% G. Rhizoma powder; D, lard 10%+5% G. Rhizoma powder; E, lard 10%+2 brix 50% ethanol extract; F, lard 10%+10 brix 50% ethanol extract; G, lard 10%+2 brix water extract; H, lard 10%+10 brix water extract. Body weight gain, although slightly higher in groups A, B, and G, did not differ significantly among dietary groups. Weights of liver, spleen, kidney, and testis were significantly higher among dietary groups. Serum total cholesterol and triglyceride concentrations were markedly higher in both control groups than group H (p<0.05). Serum HDL concentration was significantly higher in group E, and lower in group A (p<0.05). Serum LDL+VLDL concentration was significantly lower in groups E, G, and H (p<0.05). Serum testosterone level was slightly higher in groups E, D, and H. Blood glucose level was significantly higher in groups B and G, whereas lower in group H (p<0.05). Epididymal fat pad (EFP) was markedly higher in control groups than G. Rhizoma diet-fed groups (p<0.05). The results indicated that decrease in serum lipids (TC, TG, LDL+VLDL) and body fat, and increase in serum HDL and testosterone levels were higher in groups E and H extracts than groups fed G. Rhizoma powder.

Hardware Approach to Fuzzy Inference―ASIC and RISC―

  • Watanabe, Hiroyuki
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.975-976
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    • 1993
  • This talk presents the overview of the author's research and development activities on fuzzy inference hardware. We involved it with two distinct approaches. The first approach is to use application specific integrated circuits (ASIC) technology. The fuzzy inference method is directly implemented in silicon. The second approach, which is in its preliminary stage, is to use more conventional microprocessor architecture. Here, we use a quantitative technique used by designer of reduced instruction set computer (RISC) to modify an architecture of a microprocessor. In the ASIC approach, we implemented the most widely used fuzzy inference mechanism directly on silicon. The mechanism is beaded on a max-min compositional rule of inference, and Mandami's method of fuzzy implication. The two VLSI fuzzy inference chips are designed, fabricated, and fully tested. Both used a full-custom CMOS technology. The second and more claborate chip was designed at the University of North Carolina(U C) in cooperation with MCNC. Both VLSI chips had muliple datapaths for rule digital fuzzy inference chips had multiple datapaths for rule evaluation, and they executed multiple fuzzy if-then rules in parallel. The AT & T chip is the first digital fuzzy inference chip in the world. It ran with a 20 MHz clock cycle and achieved an approximately 80.000 Fuzzy Logical inferences Per Second (FLIPS). It stored and executed 16 fuzzy if-then rules. Since it was designed as a proof of concept prototype chip, it had minimal amount of peripheral logic for system integration. UNC/MCNC chip consists of 688,131 transistors of which 476,160 are used for RAM memory. It ran with a 10 MHz clock cycle. The chip has a 3-staged pipeline and initiates a computation of new inference every 64 cycle. This chip achieved an approximately 160,000 FLIPS. The new architecture have the following important improvements from the AT & T chip: Programmable rule set memory (RAM). On-chip fuzzification operation by a table lookup method. On-chip defuzzification operation by a centroid method. Reconfigurable architecture for processing two rule formats. RAM/datapath redundancy for higher yield It can store and execute 51 if-then rule of the following format: IF A and B and C and D Then Do E, and Then Do F. With this format, the chip takes four inputs and produces two outputs. By software reconfiguration, it can store and execute 102 if-then rules of the following simpler format using the same datapath: IF A and B Then Do E. With this format the chip takes two inputs and produces one outputs. We have built two VME-bus board systems based on this chip for Oak Ridge National Laboratory (ORNL). The board is now installed in a robot at ORNL. Researchers uses this board for experiment in autonomous robot navigation. The Fuzzy Logic system board places the Fuzzy chip into a VMEbus environment. High level C language functions hide the operational details of the board from the applications programme . The programmer treats rule memories and fuzzification function memories as local structures passed as parameters to the C functions. ASIC fuzzy inference hardware is extremely fast, but they are limited in generality. Many aspects of the design are limited or fixed. We have proposed to designing a are limited or fixed. We have proposed to designing a fuzzy information processor as an application specific processor using a quantitative approach. The quantitative approach was developed by RISC designers. In effect, we are interested in evaluating the effectiveness of a specialized RISC processor for fuzzy information processing. As the first step, we measured the possible speed-up of a fuzzy inference program based on if-then rules by an introduction of specialized instructions, i.e., min and max instructions. The minimum and maximum operations are heavily used in fuzzy logic applications as fuzzy intersection and union. We performed measurements using a MIPS R3000 as a base micropro essor. The initial result is encouraging. We can achieve as high as a 2.5 increase in inference speed if the R3000 had min and max instructions. Also, they are useful for speeding up other fuzzy operations such as bounded product and bounded sum. The embedded processor's main task is to control some device or process. It usually runs a single or a embedded processer to create an embedded processor for fuzzy control is very effective. Table I shows the measured speed of the inference by a MIPS R3000 microprocessor, a fictitious MIPS R3000 microprocessor with min and max instructions, and a UNC/MCNC ASIC fuzzy inference chip. The software that used on microprocessors is a simulator of the ASIC chip. The first row is the computation time in seconds of 6000 inferences using 51 rules where each fuzzy set is represented by an array of 64 elements. The second row is the time required to perform a single inference. The last row is the fuzzy logical inferences per second (FLIPS) measured for ach device. There is a large gap in run time between the ASIC and software approaches even if we resort to a specialized fuzzy microprocessor. As for design time and cost, these two approaches represent two extremes. An ASIC approach is extremely expensive. It is, therefore, an important research topic to design a specialized computing architecture for fuzzy applications that falls between these two extremes both in run time and design time/cost. TABLEI INFERENCE TIME BY 51 RULES {{{{Time }}{{MIPS R3000 }}{{ASIC }}{{Regular }}{{With min/mix }}{{6000 inference 1 inference FLIPS }}{{125s 20.8ms 48 }}{{49s 8.2ms 122 }}{{0.0038s 6.4㎲ 156,250 }} }}

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Influence of Gating and Attenuation-correction for Diagnostic Performance of Usual Rest/stress Myocardial Perfusion SPECT in Coronary Artery Disease (게이트 방법과 감쇠보정이 심근 관류 SPECT의 관상동맥질환 진단 성능에 미치는 영향)

  • Lee, Dong-Soo;Yeo, Jeong-Seok;So, Young;Cheon, Gi-Jeong;Kim, Kyeong-Min;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.33 no.2
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    • pp.131-142
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    • 1999
  • Purpose: Either gated myocardial perfusion SPECT or attenuation corrected SPECT can be used to improve specificity in the diagnosis of coronary artery disease. We investigated in this study whether gating or attenuation correction improved diagnostic performance of rest/stress perfusion SPECT in patients having intermediate pre-test likelihood of coronary artery disease. Materials and Methods: Sixty-eight patients underwent rest attenuation-corrected T1-20l/dipyridamole stress gated attenuation-corrected Tc-99m -MIBI SPECT using an ADAC vertex camera (M:F=29:39, aged $59{\pm}12$ years, coronary artery stenosis ${\geq}70%$, one vessel: 13, two vessel: 18, three vessel: 8, normal: 29). Using a five-point scale, three physicians graded the post-test likelihood of coronary artery disease for each arterial territory (1:normal, 2: possibly normal, 3:equivocal, 4. possibly abnormal, 5: abnormal). Sensitivity, specificity and area under receiver-operating-characteristic curves were compared for each operator between three methods : (A) non-attenuation-corrected SPECT; (B) gated SPECT added to (A): and (C) attenuation-corrected SPECT added to (B). Results: When grade 3 was used as the criteria for coronary artery disease, no differences in sensitivity and specificity were found between the three methods for each operator. Areas under receiver-operating-characteristic curves for diagnosis of coronary artery disease revealed no differences between each modality (p>0.05). Conclusion: In patients at intermediate risk of coronary artery disease, gated SPECT and attenuation- corrected SPECT did not improve diagnostic performance.

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Tolerance of Corn, Sorghum, Sorghum-Sudangrass Hybrid, and Pearl Millet to Simazine and Alachlor (옥수수, 수수, 수수-수단그라스 교잡종 및 진주조의 Simazine과 Alachlor에 대한 저항성)

  • 이석순;최상집
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.2
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    • pp.113-119
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    • 1989
  • In 1988 the tolerance of corn, sorghum, sorghum-sudangrass. and pearl millet hybrids to simazine and alachlor was tested in field during the growing season and pots during the summer and fall. In field and summer pot experiments(Exp.) the above mentioned four crops were tested at the ratios of simazine WP (50% ai, g/10a) ; alachlor EC (43.7% ai. ml/10a) of 130: 0, 100: 0, 70: 200, 0: 300 and 0: 400 and a sorghum hybrid was tested at 0, 50, 100, 200, 300, and 400ml/10a of alachlor and 70g/10a of simazine+ 200ml/10a of alachlor in fall pot Exp. In corn emergence rate, percent stand, plant height of seedlings, and dry matter(DM) yield were not affected by simazine and alachlor in all Exps. In sorghum and sorghum-sudangrass early growth and DM yield were not affected by simazine and alachlor in field Exp. In contrast, simazine reduced height and dry weight of seedlings slightly without any deterimental effects on emergence and survival rates. but alachlor reduced survival rate, plant height, and dry weight of seedlings significantly in summer pot Exp. In fall Exp. alachlor did not affect emergence rate of a sorghum hybrid, but survival rate, plant height, and dry weight of seedlings reduced with increased levels of alachlor when applied higher than 100ml/10a. In pearl millet simazine did not affect emergence rate, plant height, and DM yield in field, but reduced survival rate, plant height, and dry weight of seedlings in summer pot Exp. However, alachlor reduced DM yield significantly due to a lower percent stand even in the field. In summer pot Exp. although emeregence rate was slightly reduced, all seedlings were dead after emergence. Simazine did not control grasses such as Digitaria sanguinalis, Setaria viridis, Echinochloa crusgalli effectively, but controlled broadleaf weeds. Alachlor controlled all grasses, Porluraca oleracea, and Amaranthus mangostanus, but did not control Acalypha australis and Chenopodium album. A combination of simazine and alachlor controlled weeds more effectively than either simazine or alachlor alone.

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A Study for an Educational Direction in Fashion Design Subjected to Digital Environment I (디지털 환경에 따른 패션분야의 디자인 교육방향 연구 I)

  • 이미량
    • Archives of design research
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    • v.12 no.4
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    • pp.33-44
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    • 1999
  • Fashion is subjected to newness and change by itself. Fashion trend and tendency which could predict next season akeady indicated that digital and cybel11ation environment lliould be factors in fashion. Changes in future life styles and values caused by digital environment must be variables as fashion objects by themselves. Therefore digital environment of a fashion itself and that all encountered in fashion will not only be an existing situation but also an objective and a factor which must be pursued with fashionable sense in future fashion. Advanced technology and social change in relation to digital environment requires that educational method as well as its content will be changed on the scene of education for future. Thus we should seek an educational direction in fashion design for future society in which digital environment requires new paradigm. Subject to these backgrounds this study has an intension to study the change in fashion extensively influenced by expanded digital environment on a limited situational level of fashion design education and to suggest an educational direction for professional in future fashion design who will serve as a core of fashion area in the future. It is essential that education of professional in fashion for future should be achieved by digital-minded level that eagerly understands and accepts future society in which digital environment will be a main axis. It is necessary for this to make them expetience computers, digital media including CAD program. We have to note that education of digital media is more effective and applicable when accomplished in CAI level which can be related and expetienced with fashion education rather than mere functional training in media themselves. Intellectual creativity will be a vety source of producing values and national competence in 21st centtury. Education of design professional in fashion area must positively accept these environmental charactetistics in future society, as well as deeply reflect the education for the future.

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A Topic Modeling-based Recommender System Considering Changes in User Preferences (고객 선호 변화를 고려한 토픽 모델링 기반 추천 시스템)

  • Kang, So Young;Kim, Jae Kyeong;Choi, Il Young;Kang, Chang Dong
    • Journal of Intelligence and Information Systems
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    • v.26 no.2
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    • pp.43-56
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    • 2020
  • Recommender systems help users make the best choice among various options. Especially, recommender systems play important roles in internet sites as digital information is generated innumerable every second. Many studies on recommender systems have focused on an accurate recommendation. However, there are some problems to overcome in order for the recommendation system to be commercially successful. First, there is a lack of transparency in the recommender system. That is, users cannot know why products are recommended. Second, the recommender system cannot immediately reflect changes in user preferences. That is, although the preference of the user's product changes over time, the recommender system must rebuild the model to reflect the user's preference. Therefore, in this study, we proposed a recommendation methodology using topic modeling and sequential association rule mining to solve these problems from review data. Product reviews provide useful information for recommendations because product reviews include not only rating of the product but also various contents such as user experiences and emotional state. So, reviews imply user preference for the product. So, topic modeling is useful for explaining why items are recommended to users. In addition, sequential association rule mining is useful for identifying changes in user preferences. The proposed methodology is largely divided into two phases. The first phase is to create user profile based on topic modeling. After extracting topics from user reviews on products, user profile on topics is created. The second phase is to recommend products using sequential rules that appear in buying behaviors of users as time passes. The buying behaviors are derived from a change in the topic of each user. A collaborative filtering-based recommendation system was developed as a benchmark system, and we compared the performance of the proposed methodology with that of the collaborative filtering-based recommendation system using Amazon's review dataset. As evaluation metrics, accuracy, recall, precision, and F1 were used. For topic modeling, collapsed Gibbs sampling was conducted. And we extracted 15 topics. Looking at the main topics, topic 1, top 3, topic 4, topic 7, topic 9, topic 13, topic 14 are related to "comedy shows", "high-teen drama series", "crime investigation drama", "horror theme", "British drama", "medical drama", "science fiction drama", respectively. As a result of comparative analysis, the proposed methodology outperformed the collaborative filtering-based recommendation system. From the results, we found that the time just prior to the recommendation was very important for inferring changes in user preference. Therefore, the proposed methodology not only can secure the transparency of the recommender system but also can reflect the user's preferences that change over time. However, the proposed methodology has some limitations. The proposed methodology cannot recommend product elaborately if the number of products included in the topic is large. In addition, the number of sequential patterns is small because the number of topics is too small. Therefore, future research needs to consider these limitations.

Effect of Supplementation of Acanthopanax senticosus on Growth Performance, Blood Biochemical Profiles and Expression of Pro-Inflammatory Cytokines in Broiler Chicks (육계에서 가시오갈피 급여에 따른 생산성, 혈액 생화학적 성상 및 면역 사이토카인 발현에 미치는 영향)

  • Jang, In-Surk;Moon, Yang Soo;Sohn, Sea Hwan
    • Korean Journal of Poultry Science
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    • v.42 no.3
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    • pp.197-204
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    • 2015
  • This study was performed to examine the effects of dietary Acanthopanax senticosus (AS) on growth performance, immune organ weights, blood biochemical parameters and the expression of pro-inflammatory cytokines in broiler chicks. A total of 120 4-day-old birds were given a basal diet (CON) or a basal diet supplemented with 0.5% (AS1) or 1.0% (AS2) AS powder until the birds were 35 days of age. There was no difference in body weight, total gain, feed intake or immune organ weights among the treatment groups. However, the feed conversion ratio in the AS2 group was lower (p<0.05) than that in the CON group. Serum biochemical components, including AST (aspartate aminotransferase), ALT (alanine aminotransferase), albumin and total protein, were not affected by the dietary treatments, whereas glucose and triglyceride levels increased (p<0.05) in the AS2 group compared with the CON group. The AS1 group exhibited decreased mRNA expression (p<0.05) of IFN-${\gamma}$ in white blood cells and iNOS in the liver compared with the CON group. The other pro-inflammatory cytokines were unaffected by dietary AS supplementation, although there was a trend towards decreased expression of these genes, including those encoding Il-$1{\beta}$, IL-6 and TNF-${\alpha}$. In conclusion, dietary supplementation with 0.5% AS decreased the expression of several pro-inflammatory cytokines without affecting growth performance, suggesting that this supplement might be applicable as an immunoregulatory feed additive in broiler chicks.

Histological Analysis of Autologous Pericardial Tissue Used as a Small-Diameter Arterial Graft (소구경 동맥이식편으로 사용한 자가심란의 조직학적 분식)

  • Yang Ji-Hyuk;Sung Sang-Hyun;Kim Won-Gon
    • Journal of Chest Surgery
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    • v.39 no.4 s.261
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    • pp.261-268
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    • 2006
  • Background: Current vascular prostheses are still inadequate for reconstruction of small-diameter vessels. Autologous pericardium can be a good alternative for this purpose as it already possesses good blood compatibility and shows a mechanical behavior similar to that of natural arteries. However, the clinical use of autologous pericardial tissue as a small-diameter vascular graft has limitations due to mixed outcomes from uncertain biological behavior and difficulty to gain reliable patency results in animal experiments. To study this issue, we implanted fresh and glutaraldehyde-treated autologous pericardium as small-diameter arterial grafts in dogs, and compared their time-related changes histologically. Material and Method: As a form of 5mm-diameter arterial graft, one pair of autologous pericardial tissue was used for comparison between the glutaraldehyde-treated and the glutaraldehyde-untreated grafts in the bilateral carotid arteries in the same dog. The patency of the grafts were evaluated at regular intervals with Doppler ultrasonography. After the predetermined periods of 3 days, 2 weeks, 1 month, 3 months and 6 months, the grafts in each animal were explanted. The retrieved grafts were processed for light and electron microscopic analyses following gross observation. Result: Of 7 animals, 2 were excluded from the study because one died postoperatively due to bleeding and the other was documented as one side of the grafts being obstructed. All 10 grafts in the remaining 5 dogs were patent. Grossly, a variable degree of thromboses were observed in the luminal surfaces of the grafts at 3 days and 2 weeks, despite good patency. Pseudointimal smooth blood-contacting surfaces were developed in the grafts at f month and later. By light microscopy, mesothelial cell layers of the pericardial tissue were absent in all explanted grafts. Newly formed endothelial cell layers on the blood-contacting surface were observed in both the glutaraldehyde-treated and fresh grafts at 3 months and later. The collagen fibers became degraded by fragmentation in the fresh graft at 1 month and In the glutaraldehyde-treated graft at 3 months. At 6 months, the collagen layers were no longer visible in either the glutaraldehyde-treated or fresh grafts. By electron microscopy, a greater amount of coarse fibrin fibers were observed in the fresh grafts than in the glutaraldehyde-treated grafts and, more compact and well-arrayed layers were observed in the glutaraldehyde-treated grafts than in the fresh grafts. Conclusion: The glutaraldehyde-treated small-diameter pericardial arterial grafts showed a better endothelialization of the blood-contacting surface and a slower fragmentation of the collagen layers than the fresh grafts, although it has yet to be proven whether these differences are so significant as to affect the patency results between the groups.

Development of Natural Antioxidants and Whitening Agents for Cosmeceuticals

  • Kim, Jong-Pyung
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2007.11a
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    • pp.79-92
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    • 2007
  • Oxidative stress have known to be a risk factor for the degenerative processes and closely related to a lot of diseases. It is well established that antioxidants are good in protection and therapeutic means against oxidative damage. There is increasing interest in natural antioxidants and many natural antioxidants have been found and utilized as the possible protection for various diseases and skin aging. We have screened natural antioxidant agents for cosmeceuticals, nutraceuticals, and drugs as therapeutic and preventive means against oxidative stress, and have developed a number of novel antioxidants from various natural sources. A novel melanin synthesis inhibitor, Melanocin A, isolated from the metabolite of a fungal strain Eupenicillium shearii F80695 inhibited mushroom tyrosinase and melanin biosynthesis of B16 melanoma cells with $IC_{50}$ value of 9.0 nM and MIC value of $0.9\;{\mu}M$, respectively. Melanocin A also exhibited potent antioxidant activity by scavenging of DPPH and superoxide anion radicals. UV was found to increase the level of hydrogen peroxides and other reactive oxygen species (ROS) in skin tissues. This increase in ROS may not only alter the structure and function of many genes and proteins directly but may also modulate their expressions through signal transduction pathways and, ultimately, lead to skin damage. We investigated the effect of Melanocin A on UV-induced premature skin aging. Firstly, the effect of Melanocin A on UV-induced matrix metalloproteinase (MMP)-9 expression in an immortalized human keratinocyte cell line, HaCaT in vitro was investigated. Acute UV irradiation induced MMP-9 expression at both the mRNA and protein levels and Melanocin A suppressed this expression in a dose-dependent manner. We then investigated UV-induced skin changes in hairless mice in vivo by Melanocin A. Chronic exposure of hairless mouse dorsal skin to UV increased skin thickness and induced wrinkle formation and the gelatinase activities of MMP-2 and MMP-9. Moreover, Melanocin A significantly suppressed UV-induced morphologic skin changes and MMP-2 and MMP-9 expression. These results show that Melanocin A can prevent the harmful effects of UV that lead to skin aging. Therefore, we suggest that Melanocin A should be viewed as a potential therapeutic agent for preventing and/or treating premature skin aging. Terrein is a bioactive fungal metabolite isolated from Penicillium species. Terrein has a relatively simple structure and can be easily synthesized. However, the biologic effects of terrein are comparatively unknown. We found for the first time that terrein potently inhibit melanin production in melanocytes and has a strong hypopigmentary effect in a spontaneously immortalized mouse melanocyte cell line, Mel-Ab. Treatment of Mel-Ab cells with terrein (10-100 mM) for 4 days significantly reduced melanin levels in a dose-dependent manner. In addition, terrein at the same concentration also reduced tyrosinase activity. We then investigated whether terrein influences the extracellular signal-regulated protein kinase (ERK) pathway and the expression of microphthalmia-associated transcription factor (MITF), which is required for tyrosinase expression. Terrein was found to induce sustained ERK activation and MITF down-regulation, and luciferase assays showed that terrein inhibits MITF promoter activity in a dose-dependent manner. To elucidate the correlation between ERK pathway activation and a decreased MITF transcriptional level, PD98059, a specific inhibitor of the ERK pathway, was applied before terrain treatment and found to abrogate the terrein-induced MITF attenuation. Terrein also reduced the tyrosinase protein level for at least 72 h. These results suggest that terrain reduces melanin synthesis by reducing tyrosinase production via ERK activation, and that this is followed by MITF down-regulation.

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The Role of Tc-99m HMPAO Brain Perfusion SPECT in the Psychiatric Disability Evaluation of Patients with Chronic Traumatic Brain Injury (만성 외상성 뇌 손상 환자의 정신의학적 후유 장애 평가에서 Tc-99m HMPAO 뇌혈류 SPECT의 역할)

  • So, Young;Lee, Kang-Wook;Lee, Sun-Woo;Ghi, Ick-Sung;Song, Chang-June
    • The Korean Journal of Nuclear Medicine
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    • v.36 no.4
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    • pp.232-243
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    • 2002
  • Purpose: We studied whether brain perfusion SPECT is useful in the psychiatric disability evaluation of patients with chronic traumatic brain injury (TBI). Materials and Methods: Sixty-nine patients (M:F=58:11, age $39{\pm}14$ years) who underwent Tc-99m HMPAO brain SPECT, brain MRI and neuropsychological (NP) tests during hospitalization in psychiatric wards for the psychiatric disability evaluation were included; the severity of injury was mild in 31, moderate in 17 and severe in 21. SPECT, MRI, NP tests were peformed $6{\sim}61$ months (mean 23 months) post-injury. Diagnostic accuracy of SPECT and MRI to show hypoperfusion or abnormal signal intensity in patients with cognitive impairment represented by NP test results were compared. Results: Forty-two patients were considered to have cognitive impairment on NP tests and 27 not. Brain SPECT showed 71% sensitivity and 85% specificity, while brain MRI showed 62% sensitivity and 93% specificity (p>0.05, McNemar test). SPECT found more cortical lesions and MRI was superior in detecting white matter lesions. Sensitivity and specificity of 31 mild TBI patients were 45%, 90% for SPECT and 27%, 100% for MRI (p>0.05, McNemar test). Among 41 patients with normal brain MRI, SPECT showed 63% sensitivity (50% for mild TBI) and 88% specificity (85% for malingerers). Conclusion: Brain SPECT has a supplementary role to neuropsychological tests in the psychiatric disability evaluation of chronic TBI patients by detecting more cortical lesions than MRI.